Background Long QT syndrome (LQTS) is characterized by a prolonged QT interval on the electrocardiogram (ECG), a risk for sudden cardiac death. A simple 'rule of thumb' method states that if a patient's heart rate is between 60-100 bpm, the QT interval should not be more than half the R-R interval. The clinical accuracy of this method has not been tested in the elderly. Objectives To determine if the 'rule of thumb' to calculate QT interval prolongation, is accurate, compared to the corrected QT interval calculated using Bazett's formula. Secondary objectives include the prevalence of long QT and risk factors for QT prolongation. Methods The QT interval was calculated using Bazett's formula, and the 'rule of thumb' method, from ECG's collected from patients over 60 years old, on their first visit to a geriatric clinical service. Only data from patients with heart rates in the range 60-100 were analyzed. Medications and electrolyte levels were recorded. Results A total of 1000 ECGs were collected. 776 ECGs were included in the study. Prevalence of prolonged QT interval was 37.8% using Bazett's formula. Compared to Bazett's formula, the 'rule of thumb' method had a sensitivity of 65.2% and a specificity of 96.9%. ECG computer analysis calculated QTc was available for 42.5% of the cases and had a sensitivity of 58.1% and specificity of 95.3% compared to Bazett's formula. Of the 23.3% of patients taking medications known to prolong the QT interval only 38.6% had a prolonged QT interval. There was a significant association between QT interval prolongation and hypokalaemia. Conclusion The 'rule of thumb' method to determine QT interval prolongation, has high specificity but low sensitivity. This bedside measure is similar in accuracy to QT determination using an ECG computer analysis calculation in this population of older persons. / MT 2019

No description available.

Technological knowledge is of many different kinds, from experience-based know-how in the crafts to science-based knowledge in modern engineering. It is inherently oriented towards being useful in technological activities, such as manufacturing and engineering design. The purpose of this thesis is to highlight special characteristics of technological knowledge and how these affect how technology should be taught in school. It consists of an introduction, a summary in Swedish, and five papers: Paper I is about rules of thumb, which are simple instructions, used to guide actions toward a specific result, without need of advanced knowledge. One off the major advantages of rules of thumb is the ease with which they can be learnt. One of their major disadvantages is that they cannot easily be adjusted to new situations or conditions. Paper II describes how Gilbert Ryle's distinction between knowing how and knowing that is applicable in the technological domain. Knowing how and knowing that are commonly used together, but there are important differences between them which motivate why they should be regarded as different types: they are learnt in different ways, justified in different ways, and knowing that is susceptible to Gettier type problems which technological knowing how is not. Paper III is based on a survey about how Swedish technology teachers understand the concept of technological knowledge. Their opinions show an extensive variation, and they have no common terminology for describing the knowledge. Paper IV deals with non-scientific models that are commonly used by engineers, based on for example folk theories or obsolete science. These should be included in technology education if it is to resemble real technology. Different, and partly contradictory, epistemological frameworks must be used in different school subjects. This leads to major pedagogical challenges, but also to opportunities to clarify the differences between technology and the natural sciences and between models and reality. Paper V is about explanation, prediction, and the use of models in technology education. Explanations and models in technology differ from those in the natural sciences in that they have to include users' actions and intentions. / <p>QC 20140512</p>

This thesis consists of two essays and an introduction. The main theme is technological knowledge that is not based on the natural sciences.The first essay is about rules of thumb, which are simple instructions, used to guide actions toward a specific result, without need of advanced knowledge. Knowing adequate rules of thumb is a common form of technological knowledge. It differs both from science-based and intuitive (or tacit) technological knowledge, although it may have its origin in experience, scientific knowledge, trial and error, or a combination thereof. One of the major advantages of rules of thumb is the ease with which they can be learned. One of their major disadvantages is that they cannot easily be adjusted to new situations or conditions. Engineers commonly use rules, theories and models that lack scientific justification. How to include these in introductory technology education is the theme of the second essay. Examples include rules of thumb based on experience, but also models based on obsolete science or folk theories. Centrifugal forces, heat and cold as substances, and sucking vacuum all belong to the latter group. These models contradict scientific knowledge, but are useful for prediction in limited contexts where they are used when found convenient. The role of this kind of models in technology education is the theme of the second essay. Engineers’ work is a common prototype for pupils’ work with product development and systematic problem solving during technology lessons. Therefore pupils should be allowed to use the engineers’ non-scientific models when doing design work in school technology. The acceptance of these could be experienced as contradictory by the pupils: a model that is allowed, or even encouraged in technology class is considered wrong when doing science. To account for this, different epistemological frameworks must be used in science and technology education. Technology is first and foremost about usefulness, not about the truth or even generally applicable laws. This could cause pedagogical problems, but also provide useful examples to explain the limitations of models, the relation between model and reality, and the differences between science and technology. / <p>QC 20111118</p>

Idag står mänskligheten inför stora förändringar i klimatet, men en ansträngning från alla kan dessa förändringar motverkas. Detta examensarbete är en påpekning som kan leda till en bättre miljö.   Syftet med examensarbetet är att i samverkan med företaget Lönn Energi undersöka och analysera kända köldbryggor i två småhus. Som ligger i närheten av Gävle och jämföra köldbryggsandelen i husen med schablon-påslaget om 20%.  Det som ska beräknas är andelen linjära köldbryggor i förhållande till värmegenomgångskoefficienten, Som resultat visar arbetet att för de två husen som undersöktes att andelen köldbryggor i förhållande till Um går på 4,5% för huset i Årsunda och 8,4% för huset i Lingbo. / Today, humanity is facing major climate changes, but with the efforts of all, these changes can be prevented. This thesis work is a remark that can lead to a better environment.  The purpose of the thesis is to investigate and analyze known thermal bridges in two single-family houses which is located near Gävle. And to compare the thermal bridges percentage in the houses with the recom-mended addition of 20 % in collaboration with Lönn Energi.   As a result, the work shows that for the two houses examined the propor-tion of thermal bridges in relation to heat transfer coefficient Um is 4.5% for the house in Årsunda and 8.4% for the house in Lingbo.

No description available.

This thesis develops an optimal interpolation method that takes daily precipitation values collected from weather stations and produces precipitation estimates on a grid. The method, called Hybrid 2.0, combines EOF-based linear interpolation with the nearest-station method. Gridded monthly precipitation is first obtained via EOF, then distributed among days via nearest station. Hybrid 2.0 builds on an earlier method, called Hybrid 1.0, that applies an inverse-distance weighting method to obtain gridded monthly values. Hybrid 2.0 uses these monthly Hybrid 1.0 values as inputs when constructing EOF functions. The data used in this thesis were obtained from the Meteorological Service of Canada. Few weather stations were located in the northern and mountain regions of Alberta prior to 1950. As a result, the Hybrid 1.0 gridded results underestimate precipitation in these regions for that period. The main contribution of Hybrid 2.0 is a substantial reduction in this bias, obtained by implicitly taking topographic elevation into account. Bias reduction is achieved by extracting EOFs from Hybrid 1.0 output for 1951-2002, when many more stations were present in the northern and mountain regions. Hybrid 2.0 is shown to be more accurate in interpolating both monthly and daily precipitation in Alberta, when compared with Hybrid 1.0 and other methods. The thesis also provides detailed analyses of precipitation trends and droughts using the gridded Hybrid 2.0 daily values. Optimality of the selected EOF modes and sensitivity to data error in the EOF-based linear reconstruction are also discussed in this thesis. Agricultural uses of historical climate data have become extremely important. Applications include: enabling prompt, optimal decisions on market prices and disaster aid, designing future agricultural practices such as adaptation to climate and technology changes, and managing risks for agricultural producers and governments in areas such as drought monitoring. Many applications require a reliable interpolation technique to accurately reconstruct daily climate estimates onto grids of various resolutions. The gridded Hybrid 2.0 daily precipitation values produced by this thesis satisfy this requirement and can be used as inputs for many agricultural applications. / Applied Mathematics

No description available.

The thesis is divided into three chapters.1) I study how monetary policy should be optimally designed when households show financial wealth heterogeneity.Main results: thanks to its ability to affect interest payments volatility, monetary policy has real effects even in a flexible-price cashless-limit environment; second, in a setup with nominal rigidities, price stability is no longer optimal. The extent of deviation from price stability depends on the initial level of debt dispersion.2) I assess the role of housing price movements in influencing the optimal design of monetary policy. Under the optimal simple rule, housing price movements should not be a separate target variable in addition to inflation. Furthermore, the welfare loss arising from targeting housing prices becomes quantitatively more significant the higher the degree of access to the credit market.3) I analyze the effects of fiscal policy in a currency area. Results: a public spending shock in one region increases private agents demand for imports and appreciates the terms of trade; second, a countercyclical fiscal rule can restore the Taylor principle, the uniqueness of the equilibrium and reduce macro-volatility.

<p>Due to changes in the economy, the Department of Defense is requiring dramatic changes in its procurement process for major systems. These changes attempt to leverage from the large quantity of commercial software that is currently on the. market. As a result, better estimating techniques are required to properly account for software reuse. For government agencies, these techniques must be understood and applied when validating and tracking contractor performance. An industry survey was performed and subsequently two techniques were evaluated. The evaluation criteria used is consistent with the attributes of the systems engineering process. This project will evaluate the two most widely used; function point analysis and rule of thumb analysis were selected for computing the cost of a specified software intensive project.</p> / Master of Science