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Temporally structured density-dependence and population management

We used a simple discrete-time population model to investigate how temporally structured density-dependence influences a population's response to loss due to harvesting. We assumed that reproduction is a relative discrete event in time, followed by density-dependent mortality and then harvesting, or followed by harvesting and then density-dependent mortality. Such an ordering of events in time may

Combined magnetic and structural investigation of nano crystalline iron oxides: The interplay between crystal size and phase composition during FeS2 oxidation

The oxides that form during thermal oxidation of natural FeS2 (pyrite and marcasite) consist of nanometer-sized crystals of alpha-Fe2O3 and gamma-Fe2O3. This is shown with heating experiments that were made up to 650 degrees C, which resembles temperatures used in metallurgical processes. It is shown that magnetic measurements can play a key role in the investigation of this reaction, due to the u

How to kick off system innovation: a Rotterdam case study of the transition to a fuel cell transport system

Fuel cells in combination with hydrogen are expected to play an important role in a future, sustainable transport system. Recent studies have provided insight into how technological transitions may come about and may be I managed. However, there is a lack of methodologies aimed at starting off transitions or system innovations, in practice. This paper addresses this issue by presenting a methodolo

Passive and active inclusion of host proteins in human immunodeficiency virus type 1 gag particles during budding at the plasma membrane

Human immunodeficiency virus type 1 particles form by budding at the surface of most cell types. In this process, a piece of the plasma membrane is modified into an enveloped virus particle. The process is driven by the internal viral protein Pr55(gag). We have studied how host proteins in the membrane are dealt with by Pr55(gag) during budding. Are they included in or excluded from the particle?

Rotational structures near 40h in La-123

The neutron-deficient nucleus La-123 was studied via the Mo-92(Ca-40,2ap) reaction at a beam energy of 184 MeV. Previously known bands were extended to a much higher spin, and in two cases the structures are now observed near 40 (h) over bar. In addition, three new sequences were identified and linked into previously known bands. The lowest (pi,alpha)=(+,-1/2) structure displays characteristics si

Hair element concentrations in females in one acid and one alkaline area in southern Sweden.

Concentrations of 34 trace elements in hair have been determined in 47 females from an acid region in southern Sweden, who were compared with 43 females from an alkaline area. The concentrations of these elements in hair and drinking water were determined by inductively coupled plasma optical emission spectroscopy and inductively coupled plasma mass spectrometry. The hair concentrations of boron a

Who's the expert? On knowledge as praxis - a methodological approach

To establish a knowledge seeking that sheds light upon manifoldness without simplifying plurality or further exposing implicit power hegemonies, feminist scholars need to distinguish between forms of rationalist knowledge and knowledge as praxis. This article calls attention to the fact that scholars need to address how issues of habits, norms, customs and ideas are related to the production of kn

Immunological aspects on cystic fibrosis lung disease

In cystic fibrosis (CF) colonization of the airways with Pseudomonas aeruginosa is a major cause of deterioration and death. Host defence fails to clear the invading bacteria, which results in a chronic destructive inflammatory process. This thesis deals with factors in the interaction between bacteria and host defence that determine the extent of tissue damage caused by the bacteria. (I) Autoant

Towards a Theory of Implementing the Balance Scorecard: A Study in Association with the Swedish Telecommunication Firm Ericsson

There are several ways to implement and work with the Balanced Scorecard (BSC). The company Ericsson Data AB was one of the pioneers in employing the BSC in Sweden. As early adopters, they were interested in obtaining an evaluation performed by external researchers. We were fortunate to have that opportunity. During the autumn of 1998, Majvor Karlsson and Ellen Sharma had full access to the develo

Post- versus presynaptic plasticity in L-DOPA-induced dyskinesia.

L-3,4-dihydroxyphenylalanine (L-DOPA) remains the most efficacious drug for the treatment of Parkinson's disease (PD), but causes adverse effects that limit its utility. L-DOPA-induced dyskinesia (abnormal involuntary movements) is a significant clinical problem that attracts growing scientific interest. Current notions attribute the development of dyskinesia to two main factors, viz. the loss of

The three-dimensional structure of catalase from Enterococcus faecalis

Enterococcus faecalis haem catalase was crystallized using lithium sulfate at neutral pH. The crystals belong to space group R3, with unit-cell parameters a = b = 236.9, c = 198.1 Angstrom. The three-dimensional structure was determined by molecular replacement using a subunit of the Proteus mirabilis catalase structure. It was refined against 2.3 Angstrom synchrotron data to a free R factor of 21

Reactive dc magnetron sputter deposited Al2O3: large area coatings for industrial application

Stoichiometric Al2O3 films are produced with a pure Al source in the metallic state in an O2+Ar gas mixture using reactive d.c. magnetron sputtering. Substrates as large as 70×100 cm2 are uniformly coated at room temperature while moving in front of the cathode. The key to the success lies in utilizing a sufficiently high working gas pressure and a sufficiently large source-to-substrate distance.

Frequent occurrence of a variant O1 gene at the blood group ABO locus

Blood group ABO polymorphism was analysed in genomic DNA isolated from 150 blood donors by restriction endonuclease digestion of three polymerase chain reaction-amplified exons in the ABO genes and by sequencing of randomly selected samples. An anomalous O1 allele first described in a cancer cell line is now shown to account for approximately 40% of the O alleles described to date. This is 10 time