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Scintillate : An open-source graphical viewer for time-series calcium imaging evaluation and pre-processing

Background Calcium imaging is based on the detection of minute signal changes in an image time-series encompassing pre- and post-stimuli. Depending on the function of the elicited response, change may be pronounced, as in the case of a genetically encoded calcium-reporter protein, or subtle, as is the case in a bath-applied dye system. Large datasets are thus often acquired and appraised only duri

Leadership challenges of strategic research centres in relation to degree of institutionalisation

The purpose of this study was to describe and analyse leadership challenges in the organisation of strategic research centres, focusing on the relationship between organisation and the level of institutionalisation. Four main themes of leadership challenges were identified: (1) the changing university context, including relationships with top management and faculties; (2) research strategy, consid

Biophysical study of resin acid effects on phospholipid membrane structure and properties

Hydrophobic resin acids (RAs) are synthesized by conifer trees as part of their defense mechanisms. One of the functions of RAs in plant defense is suggested to be the perturbation of the cellular membrane. However, there is a vast diversity of chemical structures within this class of molecules, and there are no clear correlations to the molecular mechanisms behind the RA's toxicity. In this study

A silicon depleted North Atlantic since the Palaeogene : Evidence from sponge and radiolarian silicon isotopes

Despite being one of Earth's major geochemical cycles, the evolution of the silicon cycle has received little attention and changes in oceanic dissolved silica (DSi) concentration through geologic time remain poorly constrained. Silicon isotope ratios (expressed as δ30Si) in marine microfossils are becoming increasingly recognised for their ability to provide insight into silicon cycling. In parti

School egress data: comparing the configuration and validation of five egress modelling tools

Data were collected between 2011 and 2014 from five evacuations involving the same school buildings located in Spain. Children from 6 to 16 years of age were observed during the evacuation exercises. Background information was collected on key factors deemed to influence evacuation performance: a description of the geometry, the population involved, the procedures employed and the organization of

A combined electromagnetic and acoustic analysis of a triaxial carbon fiber weave for reflector antenna applications

Fiber composites are widely used for space applications such as antennas, solar panels and spacecraft support structures. This paper presents a combined electromagnetic and acoustic analysis of a triaxial carbon fiber weave structure, designed for ultra lightweight reflector antennas in satellite communication systems. The electromagnetic and acoustic performance of the structure are analyzed over

Activity of phenoxy-imine titanium catalysts in ethylene polymerization : A quantum chemical approach

The mechanism of ethylene polymerization on phenoxy-imine (FI) titanium catalysts was studied theoretically to identify the major factors affecting the catalytic activity. Geometry optimizations of FI ligands, octahedral titanium dichloride complexes, active cationic species, and their π‐complexes with ethylene as well as calculations of the energy profile of chain propagation were performed at th

Comparison of the complete sequence of the str operon in Salmonella typhimurium and Escherichia coli

The nucleotide (nt) sequences of the str operon in Escherichia coli K-12 and Salmonella typhimurium LT2 were completed and compared at the nt and amino acid (aa) level. The order of conservation at the nt and aa level is rpsL greater than tufA greater than rpsG greater than f usA. A striking difference is that the rpsG-encoded ribosomal protein, S7, in E. coli K-12 is 23 aa longer than in S. typhi

Fusidic acid-resistant mutants define three regions in elongation factor G of Salmonella typhimurium

We have sequenced fusA, the gene coding for elongation factor G (EF-G), in 18 different mutants of Salmonella typhimurium selected as fusidic acid resistant (FuR). In addition, we have sequenced two previously described FuR mutants from Escherichia coli. In all cases, the resistance is due to a mutation in one of three separate regions in fusA. The three clusters of mutant sites superimpose on reg

A new mutation in 16S rRNA of Escherichia coli conferring spectinomycin resistance

We report a novel mutation, C1066U in 16S rRNA which was selected for resistance to spectinomycin, an antibiotic which inhibits ribosomal translocation. The minimal inhibitory concentration (MIC) of spectinomycin determined for this mutant (15 micrograms/ml) is greater than with the wild-type plasmid (5 micrograms/ml) but lower than with the well known C1192U mutation (> 80 micrograms/ml). The C10

The introduction and expansion of biomass use in Swedish district heating systems

District heating satisfies about 60% of the heat demand in Swedish buildings. Today, more than two thirds of the heat supply to the district heating systems is based on biomass and waste, and biomass alone accounts for about half of the heat supply. The purpose of this paper is to present the Swedish experiences of introducing and expanding the use of biomass in the district heating systems and to

The dynamic structure of EF-G studied by fusidic acid resistance and internal revertants

We have previously identified 20 different fusidic acid-resistant alleles of fusA, encoding mutant forms of the ribosomal translocase EF-G. One of these, P413L, is used here as the starting point in selections for internal revertants, identifying 20 different pseudo-wild-type forms of EF-G. We have also identified two alleles of fusA previously isolated as suppressors of 4.5 S RNA deficiency. All

Effects of variety and steeping conditions on some barley components associated with colonic health

BACKGROUND: Butyric acid is produced by degradation of dietary fibre by microbiota and is crucial for maintaining a healthy colon. The physicochemical properties are important for butyric acid formation, and this study aimed to evaluate the use of malting to tailor the functional characteristics of barley dietary fibre. The effect of different steeping conditions was evaluated in laboratory-scale

Tailoring the internal structure of liquid crystalline nanoparticles responsive to fungal lipases : A potential platform for sustained drug release

Lipases are key components in the mechanisms underlying the persistence and virulence of infections by fungi, and thus also promising triggers for bioresponsive lipid-based liquid crystalline nanoparticles. We here propose a platform in which only a minor component of the formulation is susceptible to cleavage by lipase and where hydrolysis triggers a controlled phase transition within the nanopar

Rent gaps in the Spanish Crisis

Rent seeking is central to processes of financialisation and crisis formtation, not least in tourism economies. Rent seeking involves the making and taking of rent gaps geared to expand unearned incomes in the form of interest revenues from debt and rental revenues from property. Changes in built environments become increasingly determined by where rent gaps can be created and appropriated, rather

The inhibitory effects of reject water on nitrifying populations grown at different biofilm thickness

Suppression of nitrite oxidizing bacteria (NOB) is of vital importance to achieve successful, energy efficient, mainstream anammox processes for wastewater treatment. In this study, biofilm carriers from a fully nitrifying MBBR system, fed with mainstream wastewater, were temporarily exposed to reject water from sludge dewatering, to evaluate this as a possible strategy to inhibit NOB and achieve

Plant biomass, soil microbial community structure and nitrogen cycling under different organic amendment regimes; a 15N tracer-based approach

Sustainable agriculture requires nutrient management options that lead to a profitable crop yield with relatively low nitrogen (N) losses to the environment. We studied whether the addition of contrasting organic amendments together with inorganic fertilizer can promote both requirements simultaneously. In particular we studied how the chemical composition of organic amendments affects the biomass