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Do personal experiences have an impact on teaching and didactic choices in geography?

Factors influencing teachers' selection of content in geography teaching is a fundamental didactic matter.1 The purpose of the present study was to investigate whether Swedish geography teachers' informal and formal experiences have influenced their interest in geography and if so, in what way. The results disclosed that informal experiences like outings, holidays, and childhood memories have a si

Simulation of Non-linear Stochastic Differential Equations

This paper describes a numerical technique to solve non-linear stochastic differential equations of Ito and Stratonovich type. We consider Euler, fourth-order Runge-Kutta (R-K) Schemes,and other schemes with intermediate accuracy. For the purpose of investigating the Convergence of numerical solutions and to apply variable integration step length techniques the special Wiener process generator was

“With This Disease, You Take Whatever Chances There Are”—A Study on Socio-Cultural and Psychological Aspects of Experiments Regarding Huntington’s Disease

Although relatively rare, Huntington’s disease (HD) has fatal consequences. There is no cure for the disease, which leads to an early death. Worldwide, scientists are trying to develop therapeutic methods that could cure the disease, including new molecular gene therapeutic methods. At Lund University, research on HD is now about to step from animal models to trials with humans. The project is spe

Modelling of phosphate retention by Ca- and Fe-rich filter materials under flow-through conditions

Subsurface transport of orthophosphate (Pi) from fertilized agricultural fields to freshwaters may lead to eutrophication, reduced biodiversity and fish kills in inland waters. Reduction of Pi transport by means of filters in drains with Pi sorbing materials (PSMs) may be one way to improve water quality. The aims of this study were to investigate and model the effect of retention time (RT) and in

Deposition of Nutrients From Harmattan Dust in Ghana, West Africa

In order to measure dust's nutrient input on farmland in different agro-ecological zones, Harmattan dust was sampled by mats with plastic straw in Ghana between 2002-2006. The inputs of total nutrients by Harmattan dust in Ghana per Harmattan period were about 1-2 kg Ca ha-1, 0.5-2 kg K ha-1, 0.5-1.5 kg Mg ha-1 and less than 0.5 kg P ha-1. Compared with the annual input of nutrients by precipitati

Phosphate sorption by three potential filter materials as assessed by isothermal titration calorimetry

Phosphorus eutrophication of lakes and streams, coming from drained farmlands, is a serious problem in areas with intensive agriculture. Installation of phosphate (P) sorbing filters at drain outlets may be a solution. The aim of this study was to improve the understanding of reactions involved in P sorption by three commercial P sorbing materials, i.e. Ca/Mg oxide-based Filtralite-P, Fe oxide-bas

A three-step test of phosphate sorption efficiency of potential agricultural drainage filter materials

Phosphorus (P) eutrophication of lakes and streams, coming from drained farmlands, is a serious problem in areas with intensive agriculture. Installation of P sorbing filters at drain outlets may be a solution. Efficient sorbents to be used for such filters must possess high P bonding affinity to retain ortho-phosphate (Pi) at low concentrations. In addition high P sorption capacity, fast bonding

Influence of the inter tropical discontinuity on Harmattan dust deposition in Ghana

The Harmattan is a dry dust-laden continental wind, and in the boreal winter Harmattan dust plumes affects many West African countries, including Ghana. When the Harmattan is strongest the southern part of Ghana is affected by the Inter Tropical Discontinuity (ITD). In this study, we investigate if the ITD functions as a barrier, preventing long transported Harmattan dust to settle south of, and b

Sediment and nutrient deposition in Lake Volta in Ghana due to Harmattan dust

Harmattan is a dust-laden north-easterly wind that blows from the Sahara towards the Gulf of Guinea in the period November to March. It is the dominant wind in the north of Ghana while at the coast in the south it only occurs sporadically and here westerly or south-westerly winds dominate. Some of the dust is trapped in the vegetation, in lakes and other inland waters, and a little on the bare lan

Origin of Harmattan dust settled in Northern Ghana - Long transported or local dust?

The Harmattan is a dry, dust-laden continental wind which has its origin in the Bodélé Depression in the Chad basin. In Ghana the Harmattan can be experienced from November to March, when the Harmattan replaces the dominant south westerly maritime Monsoon wind. The hypothesis of this study is that the majority of dust deposited in northern Ghana may not be from the original Harmattan source in the

Glomalin-related soil protein responses to elevated CO2 and nitrogen addition in a subtropical forest : Potential consequences for soil carbon accumulation

According to the economy theory, plants should preferentially allocate photosynthate to acquire below-ground resources under elevated atmospheric carbon dioxide (eCO2) but decrease below-ground C allocation when nitrogen (N) is sufficient for plant growth. Arbuscular mycorrhizae (AM) represent a critical mechanism of below-ground nutrient acquisition for plants. The dynamics of arbuscular mycorrhi

Development and Implementation of a Mouldable Soft Magnetic Composite

Electrical machines, chokes and induction heaters are found in most homes,offices and factories all over the world. They are used to create movement, filtrate the power or to generate heat. A typical unit consist of a coil and a flux conductor material. Some of the materials have been established for over 100 years, while others are only a couple of decades old.A new flux conductor material has be

Sustainable Management of Banana Waste through Renewable Energy and Bio-Fertilizer Generation

Bananas are widely consumed fruits with over 140 metric tons produced annually. As much as 336 metric tons of banana pseudo-stems, sheaths, piths, peels and leaves are produced annually. These wastes are usually discarded via composting, aerobic decomposition, incinerated or simply allowed to rot in the fields. However, these treatments may cause serious environmental and ecological problems. Mea