249 research outputs found
Modelling the Interactions between Information and Communication Technologies and Travel Behaviour
The growing capabilities and widespread proliferation of information and communication technologies (ICT) into virtually every aspect of lifestyle, combined with the continuing challenges faced by transport systems, has ensured ongoing interest in the interactions between ICT and travel behaviour. Yet, despite more than three decades of efforts to understand these relationships, few point of consensus have so far emerged, partly due to the rapidly evolving character of ICT, and partly due to the inherent complexity of such interactions.
This thesis seeks to develop novel understandings of such interactions by introducing a number of extensions to the existing modelling frameworks. This is achieved through three interrelated research objectives which seek to explore the topic from macro, micro, and temporal perspectives. The macro perspective takes the form of a structural equation analysis of the relationships between ICT use and travel behaviour across four countries: Canada, the United States, the United Kingdom, and Norway, with the data for the latter three obtained by pooling separate datasets on ICT use and travel behaviour. The micro perspective seeks to develop a microeconomic model of an individual maximising utility through joint choice of activities, including in-travel activities, ICT use, as well as the choice of travel mode, timing and route, with the decisions motivated by contribution towards satisfaction, productivity, and consumption. The model is subsequently tested in the empirical contexts of rail business travel time, business travel time valuation, and conceptualisation of the ICT and travel behaviour interaction scenarios reported elsewhere in the literature. The final, temporal perspective analyses the comparatively least explored topic of evolution in the relationships between ICT use and travel behaviour over time. This is achieved by analysing repeated cross-sectional data using structural equation modelling, and interpreted with reference to the theory of diffusion of innovations. The thesis also discusses a number of potential research, policy and industrial applications of its empirical and theoretical contributions.Open Acces
Hybrid Technique for Incisional Hernias
Hernia is one of the most common complications post any laparotomy. Various techniques are used for the repair of incisional hernias. Hernioplasty with synthetic materials is worldwide standard, and indications to the simple suture methods are rare. Mini-invasive techniques for hernia repair have become popular since 1990 and carry many advantages. Some incisional hernias have a very large hernia sac with large loss of fascia, which makes an exclusive laparoscopic approach challenging. Moreover, some patients are found to have very dense adhesions, which makes laparoscopic approach unsafe, and almost impossible necessitating conversion from laparoscopic to open surgery. Then, the process is carried on until the safe implantation of mesh into abdominal cavity becomes possible. This has led to the birth of what is known as the hybrid technique for incisional hernia repair (laparoscopy, conversion, laparotomy, laparoscopy). Patients with large, complicated, and recurrent incisional hernias should primarily be qualified to hernioplasty with the hybrid technique, which combines the conventional open repairs (safe adhesiolysis, safe placement of laparoscopic tools into the abdominal cavity, closing the defect) with laparoscopic repair (intraperitoneal mesh placing)
Modelling the Interactions between Information and Communication Technologies and Travel Behaviour
The growing capabilities and widespread proliferation of information and communication technologies (ICT) into virtually every aspect of lifestyle, combined with the continuing challenges faced by transport systems, has ensured ongoing interest in the interactions between ICT and travel behaviour. Yet, despite more than three decades of efforts to understand these relationships, few point of consensus have so far emerged, partly due to the rapidly evolving character of ICT, and partly due to the inherent complexity of such interactions.
This thesis seeks to develop novel understandings of such interactions by introducing a number of extensions to the existing modelling frameworks. This is achieved through three interrelated research objectives which seek to explore the topic from macro, micro, and temporal perspectives. The macro perspective takes the form of a structural equation analysis of the relationships between ICT use and travel behaviour across four countries: Canada, the United States, the United Kingdom, and Norway, with the data for the latter three obtained by pooling separate datasets on ICT use and travel behaviour. The micro perspective seeks to develop a microeconomic model of an individual maximising utility through joint choice of activities, including in-travel activities, ICT use, as well as the choice of travel mode, timing and route, with the decisions motivated by contribution towards satisfaction, productivity, and consumption. The model is subsequently tested in the empirical contexts of rail business travel time, business travel time valuation, and conceptualisation of the ICT and travel behaviour interaction scenarios reported elsewhere in the literature. The final, temporal perspective analyses the comparatively least explored topic of evolution in the relationships between ICT use and travel behaviour over time. This is achieved by analysing repeated cross-sectional data using structural equation modelling, and interpreted with reference to the theory of diffusion of innovations. The thesis also discusses a number of potential research, policy and industrial applications of its empirical and theoretical contributions.Open Acces
Tryptophan metabolism in experimental necrotizing acute pancreatitis
Pancreatic encephalopathy is a serious, often lethal complication of acute pancreatitis (AP). Its pathomechanism remains obscure. We have previously described increased blood levels of quinolinic acid (QUIN) – an endogeneous neurotoxine – during edematous experimental acute pancreatitis. Several other metabolites of tryptophan (TRP) are also known to be neuroactive. The aim of the present study was to assess tryptophan and its main metabolites: kynurenine (KYN), 3-hydroxykynurenine, quinolinic acid (QUIN), kynurenic acid (KYNA), serotonin (5HT) during experimental acute necrotizing acute pancreatitis. Experimental necrotizing acute pancreatitis was induced in rats by intraductal injection of 5% sodium taurocholate. Control groups consisted of sham-operated and not operated rats. The animals were sacrificed 5 and 24 hours after the operation. We evaluated -amylase, pancreas weight and histology as parameters of pancreatitis. A simplified neurological scoring system was applied. To assess TRP and its metabolites in plasma, we used high performance liquid chromatography. Five hours after the onset of AP we found significant increase in TRP metabolites: QUIN, KYNA, KYN, and 3HKYN in the plasma of animals with AP, as compared to the control group. When assessed 24 hours after induction of AP, those changes were no longer observed in blood. Instead, a decrease in TRP level appeared. Increase in plasma QUIN was associated with neurologic disturbances. In the present study we demonstrated transient activation of kynurenine pathway during early stages of experimental necrotizing AP, with increased blood levels of QUIN, KYNA, KYN, and 3HKYN and subsequent depletion of TRP. As some kynurenine derivatives, e.g. quinolinic acid, are endogenous toxins, they might contribute to neurologic and other organs disturbances during AP
Międzynarodowe aspekty jakościowych zmian transportu samochodowego związane z elektromobilnością
The phenomenon of electrification of motor transport is more and more common and seems to be irreversible due to the pressure related to the implementation of sustainable socio-economic development. The scale of qualitative changes in motor transport in this area is so significant that it becomes the domain of the entire European Union, not individual countries. The aim of the article is to present the current difficulties related to the electrification of motor transport. It was justified that this branch of transport plays an important role in the research on qualitative changes in the energy market. Changes related to sustainable development are taking place systematically, which is expected by the society and EU regulatory authorities, but the difficult economic period of recent years is slowing down the changes related to the dissemination of electromobility. In the process of implementing electromobility, the infrastructural conditions for the development of motor transport are also important, which affects the direction, strength and scale of qualitative changes in the field of electromobility.Zjawisko elektryfikacji transportu samochodowego jest coraz powszechniejsze i wydaje się nieodwracalne ze względu na nacisk związany z wdrażaniem zrównoważonego rozwoju społeczno-gospodarczego. Skala zmian jakościowych transportu samochodowego w tym zakresie jest na tyle duża, że staje się domeną całej Unii Europejskiej, a nie poszczególnych państw. Celem artykułu jest przedstawienie trudności związanych z elektryfikacją transportu samochodowego. Uzasadniono, że ta gałąź transportu odgrywa także rolę w zmianach na rynku energii. Przemiany związane ze zrównoważonym rozwojem następują systematycznie, czego oczekuje społeczeństwo i organy regulacyjne UE, jednak trudny okres gospodarczy ostatnich lat spowalnia przemiany związane z rozpowszechnianiem elektromobilności. W procesie wdrażania elektromobilności znaczenie mają również infrastrukturalne uwarunkowania rozwoju transportu samochodowego, co wpływa na kierunek, siłę i skalę zmian jakościowych
Elektromobilność czynnikiem zmian jakościowych polskiego transportu samochodowego
Motor transport currently plays an important role in the socio-economic development of the country. It does not change the fact that the negative external costs of motor transport should be eliminated and this branch of transport should be taken into account in all sustainable development strategies. One possibility is the wider deployment of electric cars across the entire car fleet. The infrastructure and fleet of electric vehicles may be a potential element of the Polish energy market. The article presents the current difficulties related to the dissemination of electromobility in motor transport, which affect the small number of such vehicles present on the market. The low share of electric cars, in turn, reduces the possibility of their use as an element of the Polish energy market, at least in the next several years.Transport samochodowy odgrywa obecnie ważną rolę w rozwoju społeczno-gospodarczym kraju. Nie zmienia to faktu, iż należy przeciwdziałać kosztom zewnętrznym transportu samochodowego i brać pod uwagę tę gałąź transportu we wszelkich strategiach zrównoważonego rozwoju. Jedną z możliwości jest wdrożenie na szerszą skalę samochodów elektrycznych w całym parku samochodowym. Infrastruktura i flota pojazdów elektrycznych może być potencjalnym elementem polskiego rynku energii. W artykule przedstawiono aktualne trudności związane z upowszechnianiem elektromobilności transportu samochodowego, które wpływają na niewielką liczbę tego typu pojazdów na rynku. Niski udział samochodów elektrycznych wpływa z kolei na mniejsze możliwości ich wykorzystania jako elementu polskiego rynku energii, przynajmniej w perspektywie najbliższych kilku lat
Economic Growth and the Optimal Inequality of Income in the US and Sweden
Inequality of incomes is one of the significant factors forming the social capital. Two views
dominate among economists dealing with the influence of inequality of income on economic growth.
On the one hand, a too low inequality of income does not motivate people to increase the labour
productivity. A low inequality of income might result from an extended social care system
and overloading GDP with social transfers. A good example of it may be a situation when
the unemployed refuses to accept a job offer and prefers the unemployment benefit rather to a slightly
higher salary. Moreover, a lack of incentives for the employee who fails to acknowledge the economic
sense of increasing the productivity of his work might lead to the slower growth of economy.
On the other hand, a contrary view suggests that an increase of the inequality of income has
a negative impact on the economy. The accumulation of wealth by a small number of citizens raises
doubts about good use of that wealth for investments necessary for the growth of the economy.
An excessive inequality of income is confronted with disapproval of the significant part of society
and regarded as unfair and unjustified. It may also increase the crime level and decrease the trust and,
more generally, lead to the weakening of social capital.
The arguments above lead to a hypothesis that the influence of the inequality of income on
the growth of the economy has a non-linear character.
We confirmed this hypothesis in growth models of the US and Swedish economies. We assess
the historically optimal inequality of income measured by the Gini coefficient at 46% and 24% for
the US and Sweden respectively. The optimal inequality of income in Poland was assessed previously at
29%. The dissimilarities may result from the cultural differences, educational level differences, ethnic
differences and differences in diligence
The concentration of particulate matter in the barn air and its influence on the content of heavy metals in milk
Heavy metals are one of the components of smog, which is mainly the product of burning fossil fuels in residential buildings. These elements, introduced into the body of cattle by inhalation, may enter the milk. The goal of this study was to assess the impact of particulate pollution in the atmospheric air on the concentration of particulate matter in the air of a dairy cattle barn and on the content of selected heavy metals in milk from cows present in the building. Measurements were taken between November and April (148 measurement days). The calculations carried out showed a high correlation (R = + 0.95) between the concentrations of particulates measured outside and inside the barn, which is indicative of a significant impact of the atmospheric air on the particulate pollution level of the livestock building. The number of days in excess of the daily standard for PM inside was 51. The conducted analysis of the chemical composition of the milk collected under high particulate pollution (February) showed that the permitted lead level had been exceeded—21.93 µg/kg (norm 20.00 µg/kg)
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