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Sympathetic nerve stimulation influences mucociliary activity in the rabbit maxillary sinus

The effect of preganglionic sympathetic nerve stimulation on mucociliary activity in the rabbit maxillary sinus was investigated in vivo. Response to nerve stimulation was recorded photoelectrically and expressed as a percentage of the basal mucociliary activity prior to stimulation. Nerve stimulation (15 V, 5 ms) for 60 s at 2, 10 and 20 Hz stimulated mucociliary activity, the maximum increase be

Active Stabilization of Thermoacoustic Oscillation

Combustion processes serve as important sources of energy for both power generation and for transport, ranging from large scale power stations to micro turbines and aeroplane engines. Lean premixed combustion offers a potential to reduce the emission levels, but suffers from instability problems which can be overcome by the use of active control. This thesis addresses the problem of actively contr

A risk assessment of uranium in drinking water

Naturally occurring uranium is known to give rise to adverse renal effects in various species after ingestion. This short review of uranium toxicity focus on three epidemiological studies on drinking water which are compared with a pivotal study in experimental animals used as a basis for limits of uranium in drinking water or guidelines in several countries. These studies are scrutinized and disc

Prognosis in elderly men with screening-detected abdominal aortic aneurysm

OBJECTIVES: To study the natural course of screening-detected symptomless abdominal aortic aneurysm (AAA) in elderly men. SETTING: Malmo, a city in southern Sweden with 230,000 inhabitants and a single referral hospital. MATERIALS: 423 seventy-four-year-old men, randomly selected from the population and belonging to the prospective population study "Men born in 1914", were invited. 343 underwent A

Modeling CNS neurodegeneration by overexpression of disease-causing proteins using viral vectors.

Defective handling of proteins is a central feature of major neurodegenerative diseases. The discovery that neuronal dysfunction or degeneration can be caused by mutations in single cellular proteins has given new opportunities to model the underlying disease processes by genetic modification of cells in vitro or by generation of transgenic animals carrying the disease-causing gene. Recent develop

Impact of renal dysfunction on serum Prostate-Specific Antigen

Measurement of prostate-specific antigen (PSA) in blood is an important tool in detection for prostate cancer. PSA occurs in several molecular forms in blood: mainly as a free form with a molecular mass of 28 kDa; and as PSA complexed to alpha-1-antichymotrypsin, complexed PSA, with a molecular mass of 90 kDa. Total PSA comprises the sum of free PSA and complexed PSA. The percentage of free-to-tot

Evolutionsgrader hos Teloschistacéerna - en långsam process.

The evolutionary process and its impact on speciation and emergence of genera is discussed briefly for the Teloschistaceae. Many facts which have been recognized mainly from studies of morphological variation within populations in addition to analyses of structural variation from herbarium material speak for a conceivable slow evolutionary process represented in this family. Some examples are disc

Regional Nutrient Budgets in Forest Soils in a Policy Perspective

Popular Abstract in Swedish Skogen är en av Sveriges mest betydelsefulla naturresurser. Utöver det ekonomiska värdet är skogen även viktig ur ett ekologiskt, socialt och kulturellt perspektiv. För att uppnå ett långsiktigt uthålligt skogsbruk måste alla dessa aspekter beaktas. Uthålliga näringsbalanser i den brukade skogsmarken är nödvändiga för att bevara produktionsförmågan samt minska risken föSweden's forests are one of its most important natural resources, as well as being important from ecological and social perspectives. Nutrient sustainability is essential to maintain the production capacity and reduce the effects of acidification and eutrophication. Nutrient sustainability is strongly affected by anthropogenic influences such as air pollution and forestry practices. Regional asses

Denitrification at low temperatures using a suspended carrier biofilm process

The denitrification process was studied in a stirred lab-scale suspended carrier biofilm reactor at low temperatures (3–20°C). The reactor was filled to 50% with Kaldnes K1 carriers. The denitrification rate showed only a rather weak dependence on the temperature, the rate at 3°C being approximately 55% of that at 15°C. The maximum denitrification rate obtained at 15°C was 2.7 g NOx−-N m−2 carrier

Measurement of diffusion coefficients in gel beads: Random and systematic errors

The method of calculating diffusion coefficients in gel beads based on transient experiments of solute uptake from a finite volume has been studied theoretically. Monte Carlo simulation was used to investigate the effect of random errors in the concentration measurements. The influence of sampling frequency and diffusion direction was investigated. Systematic errors derived from an assumption of c

Evaluation of accuracy in activity calculations for the conjugate view method from monte carlo simulated scintillation camera images using experimental data in an anthropomorphic phantom.

Activity determination from scintillation camera images using the conjugate view method may be inaccurate because of variation in scattered radiation from adjacent organs and activity from overlapping tissues. The aim of this study was to simulate patient scintillation camera images and from these evaluate the accuracy of 2 correction methods. The contribution from overlapping tissue activity was

Into the isle of self : Nietzschean patterns and contrasts in D.H. Lawrence's The trespasser

This thesis is based on a close reading of Lawrence's novel The Trespasser from a Nietzschean point of view. By adopting this perspective it aims at giving the novel the sense of unity it has so far been alleged to lack. The analysis is preceded by a detailed discussion of the concept of literary influence. Since the purpose of this study is to illuminate what is unique in Lawrence's novel rather