Hallin and Mancini Revisited: Four Empirical Types of Western Media Systems

The analysis of media systems has become a cornerstone in the field of comparative communication research. Ten years after its publication, we revisit the landmark study in the field, Hallin and Mancini's “Comparing Media Systems”, and operationalize its framework for standardized measurement. The study at hand is, to the best of our knowledge, the first to comprehensively validate the original dimensions and models using aggregated data from the same sample of Western countries. Three out of four dimensions of media systems show relatively high levels of internal consistency, but “role of the state” should be disaggregated into 3 subdimensions. A cluster analysis reveals 4 empirical types of media systems that differentiate and extend the original typology.     

Synthesis and Stretching of Rolling Circle Amplification Products in a Flow‐Through System

Enzymatic isothermal rolling circle amplification (RCA) produces long concatemeric single‐stranded DNA (ssDNA) molecules if a small circular ssDNA molecule is applied as the template. A method is presented here in which the RCA reaction is carried out in a flow‐through system, starting from isolated surface‐tethered DNA primers. This approach combines gentle fluidic handling of the single‐stranded RCA products, such as staining or stretching via a receding meniscus, with the option of simultaneous (fluorescence) microscopic observation. It is shown that the stretched and surface‐attached RCA products are accessible for hybridization of complementary oligonucleotides, which demonstrates their addressability by complementary base pairing. The long RCA products should be well suited to bridge the gap between biomolecular nanoscale building‐blocks and structures at the micro‐ and macroscale, especially at the single‐molecule level presented here.     

Milk availability modulates weaning in the Norway rat (Rattus norvegicus).

Beginning on Day 14 postnatally, 368 Sprague-Dawley rat pups were exposed to different levels of milk supply by changing litter size of 10 dams from 8 to 4 or 12 (Exp I) or limiting temporally Ss' access to a lactating dam (1 of 36) to 8, 14, or 24 hrs/day (Exp II). Both manipulations accelerated weaning in milk-deprived Ss. By adding solid food and water to their diet, early weaning Ss compensated for the negative energy consequences of milk reduction and achieved premanipulation growth rates. Milk availability thus appears to affect weaning, and it is suggested that the developmental changes in the nutritive energy balance between mother and offspring contribute to the emergence of independent ingestion. (43 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Authorship Attribution with Support Vector Machines

In this paper we explore the use of text-mining methods for the identification of the author of a text. We apply the support vector machine (SVM) to this problem, as it is able to cope with half a million of inputs it requires no feature selection and can process the frequency vector of all words of a text. We performed a number of experiments with texts from a German newspaper. With nearly perfect reliability the SVM was able to reject other authors and detected the target author in 60–80% of the cases. In a second experiment, we ignored nouns, verbs and adjectives and replaced them by grammatical tags and bigrams. This resulted in slightly reduced performance. Author detection with SVMs on full word forms was remarkably robust even if the author wrote about different topics.     

Modelling the dynamics of the yeast pheromone pathway

We present a mathematical model of the dynamics of the pheromone pathways in haploid yeast cells of mating type MATa after stimulation with pheromone alpha-factor. The model consists of a set of differential equations and describes the dynamics of signal transduction from the receptor via several steps, including a G protein and a scaffold MAP kinase cascade, up to changes in the gene expression after pheromone stimulation in terms of biochemical changes (complex formations, phosphorylations, etc.). The parameters entering the models have been taken from the literature or adapted to observed time courses or behaviour. Using this model we can follow the time course of the various complex formation processes and of the phosphorylation states of the proteins involved. Furthermore, we can explain the phenotype of more than a dozen well-characterized mutants and also the graded response of yeast cells to varying concentrations of the stimulating pheromone.     

Sodium appetite in lactating rats.

Lactating rats that were given free access to sodium-deficient food, water, and 0.51 M NaCl solution showed no evidence of sodium appetite. The estimated daily loss of 1–2 mEq Na in milk was replaced by basal daily intake of 2–5 ml of saline. Sodium loss in urine was minimal, but milk sodium concentration was unchanged, and pups grew normally. Saline intake was enhanced when lactating rats that had been maintained on standard laboratory chow were injected with 30% polyethylene glycol solution to reduce plasma volume but no more so than when virgin female rats or male rats were similarly colloid-treated. Lactating rats markedly increased their intake of NaCl solution after simply depriving them of dietary sodium for 4 days, whereas male and virgin female rats did not. These findings indicate that pronounced sodium appetite does not invariably accompany lactation in rats, although it can occur whenever such animals become hypovolemic or sodium deficient. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Predominant strains of thermophilic Campylobacter spp. in a German poultry slaughterhouse

Campylobacter causes bacterial diarrhoea in man and is a common foodborne pathogen, that has been associated mainly with poultry carcasses and processed poultry products as well as with drinking water. Genotyping of Campylobacter spp. from poultry was done in order to prove if predominant stable strains in the food chain are present. The influence of the slaughter process on the stability should be determined. Thermophilic Campylobacter spp. from eight poultry flocks were isolated from cloacal swabs, carcasses and offal at different abattoir processing steps to determine their stability. DNA-fingerprinting was done using Pulsed-Field Gel Electrophoresis (PFGE) with two enzymes (SmaI and KpnI) and ribotyping. More than 150 Campylobacter strains were ribotyped and these data were combined with the results of PFGE. Molecular typing showed that strains found in cloacal swabs before processing could also be isolated from carcasses and offal at different processing steps representing predominating stable strains. Strains with varying molecular pattern could additionally be detected at different processing steps. Both genotyping methods identified in agreement flock-specific strains. These remained stable through the slaughter of poultry and were not altered through the slaughter process. Despite the known genetic variability of thermophilic Campylobacter, stable predominant strains could be identified in the poultry slaughter process and those strains can thus enter the food chain.     

Model for the influence of mass transport on enzymatic hydrolysis of polysaccharides

In this paper enzymatic hydrolysis reactions have been considered as integration-limited reactions analogous to crystal growth. Based on the mathematical formulation of diffusion of polysaccharide substrate molecules to binding sites of the enzyme, integration kinetics were derived and compared to measured data. Significant is the measured and calculated decrease of the ratio of the specific activity and the Michaelis-Menten parameter with increasing molar mass of the enzymes with an exponent more than unity.     

Micropatterned Ceramic Surfaces by Coating with Filled Preceramic Polymers

Surface structures in micrometer scale were prepared on different substrates by a coating process using particle-filled slurries based on a blend of preceramic polymers. Parameters like solvent fraction, substrate material, filler particle size, and layer thickness were varied. Demixing reactions of solvent and polymers led to surface structures with pores of 1–60 μm in diameter. The solubility parameters δ_t of the polysiloxanes used are about 18.7 MPa^1/2 for poly(methyl phenyl vinyl siloxane) and 19.5 MPa^1/2 for poly(methyl siloxane), respectively. By pyrolysis of the green layers, ceramic coatings were obtained by keeping the particular surface structures.