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The effect of silver ions and chlorine on the survival of Staphylococcus aureus and Bacillus cereus in dishwater

This paper investigates the effect of chlorine and silver ion solutions on the survival of Bacillus cereus (vegetative phase) and Staphylococcus aureus in batch cultures, representing dishwater. Dishwater contains organic matter and bacteria and bacterial activities are partly reduced by high pH (11-12) and temperature (55-65 degrees C) in professional and domestic dishwashers. in manual dishwashi

The balance between sexual and asexual reproduction in plants living in variable environments

The balance between sexual and asexual propagule production is studied in an evolutionary model where plants produce the two kinds of propagules in genetically determined proportions. The male function of plants producing asexual propagules can be varied, and the sexual and asexual propagules carry different probabilities to turn into new reproductive individuals. These fitnesses may vary over yea

Benefits of Virtual Characters in Computer Based Learning Environments: Claims and Evidence

Pedagogical theory of today gives high priority to social components of learning. Within the field of computer supported learning there are many attempts to acknowledge this. One approach involves the addition of virtual characters to electronic learning environments. Such character enhanced systems are the focus of the present article. Firstly, a systematic overview is given of pedagogical benefi

Statistical Estimation and Interpretation of Trends in Water Quality Time Series

Three approaches to trend analysis of water quality time series are discussed: (1) seasonal model, with a test for trend based on ranks of observations, with observations assumed to be m dependent; (2) transfer function noise model, in which covariate series may be included by means of transfer functions, with the remaining noise modeled as a seasonal autoregressive moving average process; and (3)

Biomass and composition of understory vegetation and the forest floor carbon stock across Siberian larch and mountain birch chronosequences in Iceland

Changes in understory biomass, forest floor carbon (C) stock and vegetation composition were studied in six age-classes of Siberian larch (Larix sibirica) and two age-classes of native birch (Betula pubescens) in Iceland. The ground vegetation was less in the larch during the thicket stage and in the old-growth birch compared to a treeless pasture. Understory biomass was strongly related to canopy

Factors affecting attitudes towards medical abortion in Lithuania

Objective Surgical abortion in Lithuania is governed by a 1994 ministerial decree that made it legal for any woman 16 or older. This article seeks to determine the key demographic factors in Lithuanian attitudes towards medical abortion, which is currently not legal. Methods A random sample of the adult population was asked if they supported medical abortion. The dependent variable of attitude tow

Hand function after nerve repair.

Treatment of injuries to major nerve trunks in the hand and upper extremity remains a major and challenging reconstructive problem. Such injuries may cause long-lasting disabilities in terms of lost fine sensory and motor functions. Nowadays there is no surgical repair technique that can ensure recovery of tactile discrimination in the hand of an adult patient following nerve repair while very you

Detecting shifts of transmission areas in avian blood parasites - a phylogenetic approach

We investigated the degree of geographical shifts of transmission areas of vector-borne avian blood parasites (Plasmodium, Haemoproteus and Leucocytozoon) over ecological and evolutionary timescales. Of 259 different parasite lineages obtained from 5886 screened birds sampled in Europe and Africa, only two lineages were confirmed to have current transmission in resident bird species in both geogra

Genotyping of hepatitis C virus isolates by a modified polymerase chain reaction assay using type specific primers: epidemiological applications

A polymerase chain reaction (PCR)-based assay using primers against the hepatitis C core gene has been described [Okamoto et al. (1992a): Journal of General Virology 73:673-679]. Within the two major HCV genotypes 1 and 2, the Okamoto system identifies two subtypes each (1a, 1b and 2a, 2b, respectively). Typing is achieved by a primary PCR with consensus primers followed by a nested PCR with type

Effects of malaria double infection in birds: one plus one is not two.

Avian malaria parasites are supposed to exert negative effects on host fitness because these intracellular parasites affect host metabolism. Recent advances in molecular genotyping and microscopy have revealed that coinfections with multiple parasites are frequent in bird-malaria parasite systems. However, studies of the fitness consequences of such double infections are scarce and inconclusive. W

Gate-defined quantum-dot devices realized in InGaAs/InP by incorporating a HfO2 layer as gate dielectric

Gate-defined quantum dots in an InGaAs/InP heterostructure are realized by incorporating a high-kappa HfO2 material as a gate dielectric using atomic layer deposition. The fabricated quantum-dot devices show Coulomb blockade effect at low temperature. The Coulomb blockade current peaks are found to shift in pairs with the magnetic field applied perpendicular to the quantum-dot plane, due to the fi

Restorative neurology in movement disorders

Cell replacement for restoration of neurological functions in patients with movement disorders has been investigated for more than 15 years. Initial attempts used autologous adrenal medulla grafts implanted into the denervated striatum of patients with Parkinson's disease (PD). This approach was soon abandoned in favor of intrastriatal implantation of human embryonic mesencephalic tissue, rich in

Democratization and Women's Empowerment: The Effects of Electoral Systems, Participation and Repetition in Africa.

This article investigates three hypotheses suggested in the literature on women's political empowerment, operationalized here as increased legislative representation. These hypotheses are that (1) electoral systems manipulate women's political empowerment; (2) increased popular participation empowers women in particular; and (3) accumulated experience gained over several electoral cycles facilitat

The potential of polymeric cryogels in bioseparation

This is a review discussing the production and properties of cryogels (from the Greek κριoσ (kryos) meaning frost or ice), immobilization of ligands in cryogels and the application of affinity cryogels in bioseparation. Cryotropic gel formation proceeds in a non-frozen liquid microphase existing in the macroscopically frozen sample. Due to the cryoconcentration of gel precursors in the non-frozen

Two major classes in the M protein family in group A streptococci

The M protein family of molecules in the group A streptococcus comprises a number of cell surface proteins that interact with the immune system of the host. One of the proteins in this family is the IgA receptor Arp4, which has C repeats similar to those that characterize the known M proteins. The streptococcal strain expressing Arp4 also expresses a second immunoglobulin-binding protein, Mrp4, wh

Risk of collapse in the eastern Baltic cod fishery

The eastern Baltic cod fishery, as many fisheries worldwide, is experiencing a major crisis. The combination of current environmental conditions, fishing mortality rates, and stock size indicates that this fishery is not sustainable. In order to rebuild the population and sustain the fishery in the future, it is essential to define a biologically appropriate exploitation level. In this paper, we t

Photochemical reactivity of aquatic macrophyte leachates: abiotic transformations and bacterial response

We evaluated the influence of UV radiation exposure time on abiotic transformations of leachates from 2 aquatic macrophytes: Phragmites australis and Hydrocaris morsus-ranae. In addition, we studied the influence of phototransformations of DOM on bacterial growth. Sterile filtered leachates were exposed to UV radiation for 5, 10, 24, 48, 72 and 120 h or kept in the dark. Dissolved inorganic carbon