10 resultados para Point Pleasant, Battle of, W. Va., 1774.

em Helda - Digital Repository of University of Helsinki


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We report measurements of the polarization of W bosons from top-quark decays using 2.7 fb^-1 of ppbar collisions collected by the CDF II detector. Assuming a top-quark mass of 175 GeV/c^2, three measurements are performed. A simultaneous measurement of the fraction of longitudinal (f_0) and right-handed (f_+) W bosons yields the model-independent results f_0 = 0.88 \pm 0.11 (stat) \pm 0.06 (syst) and f_+ = -0.15 \pm 0.07 (stat) \pm 0.06 (syst) with a correlation coefficient of -0.59. A measurement of f_0 (f_+) constraining f_+ (f_0) to its standard model value of 0.0 (0.7) yields f_0 = 0.70 \pm 0.07 (stat) \pm 0.04 (syst) (f_+ = -0.01 \pm 0.02 (stat) \pm 0.05 (syst)). All these results are consistent with standard model expectations.

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Matti Laurila (1895 1983) This is a biographical research of a Jaeger officer, a Civil Guard Chief, a Field Commander Matti Laurila. A broader practice of qualitative methods was utilized in the research. The main aim is a permanent reconstruction and reinterpretation of past events through the experiences of the study object. The life and times of Laurila are intertwined with the crucial events that led to the Finnish Declaration of Independence. Afterwards he helped to ensure that the young republic also stayed independent. As a Jaeger in the winter of 1917 Laurila witnessed an incident he would never forget. After disobeying a direct order, Sven Saarikoski from Lapua was shot dead by his commanding officer, K. A. Ståhlberg, on the ice of the river Aa. Laurila faced the horrors of war at closer quarters, for he lost his father and his brother in the battle of Länkipohja on 16th March 1918. This battle was a major turning point for Laurila and profoundly influenced the rest of his life. The relationship between Laurila and his superiors was problematic almost throughout his military career, haunted as he was by the memory of Sven Saarikoski's execution and the losses in Länkipohja The position of Laurila as an authority in South Ostrobothnia was a key factor in preventing the extreme right from rallying enough Civil Guard troops to escalate the embryonic Mäntsälä rebellion of 1932. After the rebellion Laurila routinely opposed anything he saw as a threat to the independence of the Civil Guard. He would flatly refuse to even consider the integration of the Civil Guard into the national defence force. His uncompromising stand in this matter annoyed some among the higher ranking officers. After the Winter War Laurila got himself into a dispute with Jaeger Colonel H. E. Hannuksela that would have long-lasting consequences. The conflicts between them became widely known in the attack phase of the Continuation War in 1941 at the latest. Laurila had to give up his military career at the end of 1944. In the years that followed he did what he could to ensure that the South Ostrobothnia Civil Guard patrimony remained in the province. Laurila's position as a respected authority in South Ostrobothnia remained unchanged until his death.

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This thesis studies the intermolecular interactions in (i) boron-nitrogen based systems for hydrogen splitting and storage, (ii) endohedral complexes, A@C60, and (iii) aurophilic dimers. We first present an introduction of intermolecular interactions. The theoretical background is then described. The research results are summarized in the following sections. In the boron-nitrogen systems, the electrostatic interaction is found to be the leading contribution, as 'Coulomb Pays for Heitler and London' (CHL). For the endohedral complex, the intermolecular interaction is formulated by a one-center expansion of the Coulomb operator 1/rab. For the aurophilic attraction between two C2v monomers, a London-type formula was derived by fully accounting for the anisotropy and point-group symmetry of the monomers.

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This study aims at improving understanding of the interactions of livelihoods and the environment focusing on both socio-economic and biodiversity implications of land use change in the context of population pressure, global and local markets, climate change, cultural and regional historical factors in the highlands of East Africa. The study is based on three components (1) two extensive livelihood surveys, one on Mt. Kilimanjaro in Tanzania and the other in the Taita Hills of Kenya, (2) a land use change study of the southern slopes of Mt. Kilimanjaro focusing on land use trends between 1960s and 1980s and 1980s and 2000 and (3) a bird diversity study focusing on the potential impacts of the future land use change on birds in the main land use types on the slopes and the adjacent plains of Mt. Kilimanjaro. In addition, information on the highlands in Embu and the adjacent lowlands in Mbeere of Kenya are added to the discussion. Some general patterns of livelihood, land use and environment interactions can be found in the three sites. However, the linkages are very complex. Various external factors at different times in history have influenced most of the major turning points. Farmers continually make small adaptations to their farming practices, but the locally conceived alternatives are too few. Farmers lack specific information and knowledge on the most suitable crops, market opportunities and the quality requirements for growing the crops for markets. Population growth emerges as the most forceful driver of land use and environmental change. The higher altitudes have become extremely crowded with population densities in some areas higher than typical urban population densities. Natural vegetation has almost totally been replaced by farmland. Decreasing farm size due to population pressure is currently threatening the viability of whole farming systems. In addition, capital-poor intensification has lead to soil fertility depletion. Agricultural expansion to the agriculturally marginal lowlands has created a new and distinct group of farmers struggling constantly with climate variability causing frequent crop failures. Extensification to the fragile drylands is the major cause of fragmentation and loss of wildlife habitat. The linkages between livelihoods, land use and the environment generally point to degradation of the environment leading to reduced environmental services and ecosystem functions. There is no indication that the system is self-regulating in this respect. Positive interventions will be needed to maintain ecosystem integrity.

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Population dynamics are generally viewed as the result of intrinsic (purely density dependent) and extrinsic (environmental) processes. Both components, and potential interactions between those two, have to be modelled in order to understand and predict dynamics of natural populations; a topic that is of great importance in population management and conservation. This thesis focuses on modelling environmental effects in population dynamics and how effects of potentially relevant environmental variables can be statistically identified and quantified from time series data. Chapter I presents some useful models of multiplicative environmental effects for unstructured density dependent populations. The presented models can be written as standard multiple regression models that are easy to fit to data. Chapters II IV constitute empirical studies that statistically model environmental effects on population dynamics of several migratory bird species with different life history characteristics and migration strategies. In Chapter II, spruce cone crops are found to have a strong positive effect on the population growth of the great spotted woodpecker (Dendrocopos major), while cone crops of pine another important food resource for the species do not effectively explain population growth. The study compares rate- and ratio-dependent effects of cone availability, using state-space models that distinguish between process and observation error in the time series data. Chapter III shows how drought, in combination with settling behaviour during migration, produces asymmetric spatially synchronous patterns of population dynamics in North American ducks (genus Anas). Chapter IV investigates the dynamics of a Finnish population of skylark (Alauda arvensis), and point out effects of rainfall and habitat quality on population growth. Because the skylark time series and some of the environmental variables included show strong positive autocorrelation, the statistical significances are calculated using a Monte Carlo method, where random autocorrelated time series are generated. Chapter V is a simulation-based study, showing that ignoring observation error in analyses of population time series data can bias the estimated effects and measures of uncertainty, if the environmental variables are autocorrelated. It is concluded that the use of state-space models is an effective way to reach more accurate results. In summary, there are several biological assumptions and methodological issues that can affect the inferential outcome when estimating environmental effects from time series data, and that therefore need special attention. The functional form of the environmental effects and potential interactions between environment and population density are important to deal with. Other issues that should be considered are assumptions about density dependent regulation, modelling potential observation error, and when needed, accounting for spatial and/or temporal autocorrelation.

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The Golgi complex is a central organelle of the secretory pathway, responsible for a range of post-translational modifications, as well as for membrane traffic to the plasma membrane and to the endosomal-lysosomal pathway. In addition, this organelle has roles in cell migration, in the regulation of traffic, and as a mitotic check point. The structure of the Golgi complex is highly dynamic and able to respond to the amount of cargo being transported and the stage of the cell cycle. The Golgi proteome reflects the functions and structure of this organelle, and can be divided into three major groups: the Golgi resident proteins (e.g. modification enzymes), the Golgi matrix proteins (involved in structure and tethering events), and trafficking proteins (e.g. vesicle coat proteins and Rabs). The Golgi proteome has been studied on several occasions, from both rat liver and mammary gland Golgi membranes using proteomic approaches, but still little more than half of the estimated Golgi proteome is known. Nevertheless, methodological improvements and introduction of shotgun proteomics have increased the number of identified proteins, and especially the number of identified transmembrane proteins. Cartilage, even though not a typical tissue in which to study membrane traffic, secretes large amounts of extracellular matrix proteins that are extensively modified, especially by amino acid hydroxylation, glycosylation and sulfation. Furthermore, the cartilage ECM contains several, large oligomeric proteins (such as collagen II) that are difficult to assemble and transport. Indeed, cartilage has been shown to be susceptible to changes both in secretory pathway (e.g. the COPII coat assembly) and in post-translational modifications (e.g. heparan sulfate formation). Dental follicle, and the periodontal ligament (PDL) that it forms, are another type of connective tissue, and they have a role in anchoring teeth to bone. This anchorage is achieved by numerous matrix fibres that connect the bone matrix with the cementum. These tissues have in common the secretion of large matrix molecules. In this study the Golgi proteome was analysed from purified, stacked Golgi membranes isolated from rat liver. The identified, extensive proteome included a protein similar to Ab2-095, or Golgi protein 49kDa (GoPro49), which was shown to localise to the Golgi complex as an EGFP fusion protein. Surprisingly, in situ hybridisation showed the GoPro49 expression to be highly restricted to different mesenchymal tissues, especially in cartilage, and this expression pattern was clearly developmentally regulated. In addition to cartilage, GoPro49 was also expressed in the dental follicle, but was not observed in the mature PDL. Importantly, GoPro49 is the first specific marker for the dental follicle. Endogenous GoPro49 protein co-localised with β-COP in both chondrosarcoma and primary dental follicle cell lines. The COPI staining in these cells was highly dynamic, showing a number of tubules. This may reflect the type of secretory cargo they secrete. Currently GoPro49 is the only Golgi protein with such a restricted expression pattern.

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The outcome of the successfully resuscitated patient is mainly determined by the extent of hypoxic-ischemic cerebral injury, and hypothermia has multiple mechanisms of action in mitigating such injury. The present study was undertaken from 1997 to 2001 in Helsinki as a part of the European multicenter study Hypothermia after cardiac arrest (HACA) to test the neuroprotective effect of therapeutic hypothermia in patients resuscitated from out-of-hospital ventricular fibrillation (VF) cardiac arrest (CA). The aim of this substudy was to examine the neurological and cardiological outcome of these patients, and especially to study and develop methods for prediction of outcome in the hypothermia-treated patients. A total of 275 patients were randomized to the HACA trial in Europe. In Helsinki, 70 patients were enrolled in the study according to the inclusion criteria. Those randomized to hypothermia were actively cooled externally to a core temperature 33 ± 1ºC for 24 hours with a cooling device. Serum markers of ischemic neuronal injury, NSE and S-100B, were sampled at 24, 36, and 48 hours after CA. Somatosensory and brain stem auditory evoked potentials (SEPs and BAEPs) were recorded 24 to 28 hours after CA; 24-hour ambulatory electrocardiography recordings were performed three times during the first two weeks and arrhythmias and heart rate variability (HRV) were analyzed from the tapes. The clinical outcome was assessed 3 and 6 months after CA. Neuropsychological examinations were performed on the conscious survivors 3 months after the CA. Quantitative electroencephalography (Q-EEG) and auditory P300 event-related potentials were studied at the same time-point. Therapeutic hypothermia of 33ºC for 24 hours led to an increased chance of good neurological outcome and survival after out-of-hospital VF CA. In the HACA study, 55% of hypothermia-treated patients and 39% of normothermia-treated patients reached a good neurological outcome (p=0.009) at 6 months after CA. Use of therapeutic hypothermia was not associated with any increase in clinically significant arrhythmias. The levels of serum NSE, but not the levels of S-100B, were lower in hypothermia- than in normothermia-treated patients. A decrease in NSE values between 24 and 48 hours was associated with good outcome at 6 months after CA. Decreasing levels of serum NSE but not of S-100B over time may indicate selective attenuation of delayed neuronal death by therapeutic hypothermia, and the time-course of serum NSE between 24 and 48 hours after CA may help in clinical decision-making. In SEP recordings bilaterally absent N20 responses predicted permanent coma with a specificity of 100% in both treatment arms. Recording of BAEPs provided no additional benefit in outcome prediction. Preserved 24- to 48-hour HRV may be a predictor of favorable outcome in CA patients treated with hypothermia. At 3 months after CA, no differences appeared in any cognitive functions between the two groups: 67% of patients in the hypothermia and 44% patients in the normothermia group were cognitively intact or had only very mild impairment. No significant differences emerged in any of the Q-EEG parameters between the two groups. The amplitude of P300 potential was significantly higher in the hypothermia-treated group. These results give further support to the use of therapeutic hypothermia in patients with sudden out-of-hospital CA.

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We present a measurement of the top quark pair production cross section in ppbar collisions at sqrt(s)=1.96 TeV using a data sample corresponding to 1.7/fb of integrated luminosity collected with the Collider Detector at Fermilab. We reconstruct ttbar events in the lepton+jets channel. The dominant background is the production of W bosons in association with multiple jets. To suppress this background, we identify electrons from the semileptonic decay of heavy-flavor jets. We measure a production cross section of 7.8 +/- 2.4 (stat) +/- 1.6 (syst) +/- 0.5 (lumi) pb. This is the first measurement of the top pair production cross section with soft electron tags in Run II of the Tevatron.

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Starting point in the European individualistic copyright ideology is that an individual author creates a work and controls the use of it. However, this paper argues that it is (and has always been) impossible to control the use of works after their publication. This has also been acknowledged by the legislator, who has introduced collective licensing agreements because of this impossibility. Since it is impossible to rigorously control the use of works this writing "Rough Justice or Zero Tolerance - Reassessing the Nature of Copyright in Light of Collective Licensing" examines what reality of copyright is actually about. Finding alternative (and hopefully more "true") ways to understand copyright helps us to create alternative solutions in order to solve possible problems we have as it comes e.g. to use of content in online environment. The paper makes a claim that copyright is actually about defining negotiation points for different stakeholders and that nothing in the copyright reality prevents us from defining e.g. a new negotiation point where representatives of consumers would meet representatives of right holders in order to agree on the terms of use for certain content types in online environment.