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Impacts of aerosol chemical composition on microphysics and precipitation in deep convection

Aerosols affect precipitation by modifying cloud properties such as cloud droplet number concentration (CDNQ. Aerosol effects on CDNC depend on aerosol properties such as number concentration, size spectrum, and chemical composition. This study focuses on the effects of aerosol chemical composition on CDNC and, thereby, precipitation in a mesoscale cloud ensemble (MCE) driven by deep convective cl

Binding and the effect of the red kidney bean lectin, phytohaemagglutinin, in the gastrointestinal tract of suckling rats

Enteral exposure of suckling rats to phytohaemagglutinin (PHA) has been shown to induce growth and precocious functional maturation of the gastrointestinal tract. The aim of the present study was to explore the mechanism of this action. Suckling rats, 14 d old, were fed a single dose of PHA (0.05 mg/g body weight) or saline. The binding of PHA to the gut epithelium and its effect on the morphology

Hypersensitivity to noradrenaline in human omental vein but not artery isolated from a patient with idiopathic orthostatic hypotension.

We investigated the smooth muscle contraction in response to noradrenaline (NA), endothelin-1 (ET) and 5-hydroxytryptamine (5-HT) in the omental artery and vein segments from a 67-year-old woman with idiopathic orthostatic hypotension. The blood vessels were obtained during the abdominal surgery and investigated in vitro. Noradrenaline, endothelin-1 and 5-hydroxytryptamine all induced a contractio

Temperature measurements of single droplets by use of laser-induced phosphorescence

A novel technique for measuring droplet temperatures has been demonstrated. Laser-induced phosphorescence from thermographic phosphors, seeded to distilled water and iso-octane, was used to measure temperatures of single falling droplets. The phosphors were excited by the fourth and third harmonies of a Nd:YAG laser. The subsequent emission was evaluated by spectral and temporal investigations of

Cytogenetic and molecular genetic evolution of chronic myeloid leukemia.

Chronic myeloid leukemia (CML) is genetically characterized by the presence of the reciprocal translocation t(9;22)(q34;q11), resulting in a BCR/ABL gene fusion on the derivative chromosome 22 called the Philadelphia (Ph) chromosome. In 2-10% of the cases, this chimeric gene is generated by variant rearrangements, involving 9q34, 22q11, and one or several other genomic regions. All chromosomes hav

Porous polymaleimide networks

Porous network structures were prepared by in situ polymerisation of a mixture of N-phenylmaleimide and 1, 1'-(methylenedi-4,1-plienylene)bismaleimide (95:5 w/w) in poly(vinylidene difluoride-co-hexafluoropropylene) (PVDH). The mixture of the maleimide monomers was found to form thermoreversible gels with PVDH. Thermodynamic analysis of the gelation process using calorimetry data indicated the for

Older pedestrians’ perceptions of the outdoor environment in a year-round perspective

This paper focuses on older peoples’ needs as pedestrians by examining their perceptions of the outdoor environment in both bare-ground and snow/ice conditions. Qualitative and quantitative methods are used, including focus group interviews, participant observations, and questionnaires. The results show that older people consider accessibility/usability issues as very important and that the import

Fracture mechanics analysis of microcracks in thermally cycled thermal barrier coatings

The effects from thermal shock loading on pre-existing microcracks within thermal barrier coatings (TBCs) have been investigated through a finite element based fracture mechanical analysis. The TBC system consists of a metallic bond coat and a ceramic top coat. The rough interface between the top and bond coats holds an alumina oxide layer. Stress concentrations at the interface due to the interfa

Carbon nanorings: A challenge to theoretical chemistry

High-level quantum-chemical methods show that the binding in the inclusion complex of hexamethylbenzene (HMB) in 6-cycloparaphenitacetylene (6-CPPA) cannot be explained only in terms of electrostatic interactions-caused by the polarization associated to curved a-conjugated systems-and the inclusion of dispersion forces is definitely needed. The theoretical description of van der Wools interactions

Linkage mapping reveals sex-dimorphic map distances in a passerine bird

Linkage maps are lacking for many highly influential model organisms in evolutionary research, including all passerine birds. Consequently, their full potential as research models is severely hampered. Here, we provide a partial linkage map and give novel estimates of sex-specific recombination rates in a passerine bird, the great reed warbler (Acrocephalus arundinaceus). Linkage analysis of genot

Cryptanalysis of Achterbahn

We present several attacks against the Achterbahn stream cipher, which was proposed to the eSTREAM competition. We can break the reduced and the full version with complexity of 2 55 and 2 61 steps. Extensions of our attacks are also described to break modified versions of the Achterbahn stream cipher, which were proposed following the publication of preliminary cryptanalysis results. These attacks

An X-ray absorption and photoemission study of the electronic structure of Ni porphyrins and Ni N-confused porphyrin

Investigations of chemical bonding and electronic structure features for polycrystalline (porphyrinato)nickel (II) (NiP, the simplest Ni porphyrin), (5,10,15,20-tetraphenylporphyrinato)nickel (II) (NiTPP) and (2-aza-21-carba-5,10,15,20-tetraphenylporphyrinato)nickel (II) (N-confused NiTPP, NiNCTPP) have been performed by means of high-resolution soft x-ray absorption and x-ray photoemission spectr

Stromal cell-derived inducing activity does not promote dopaminergic differentiation, but enhances differentiation and proliferation of neural stem cell-derived astrocytes.

Previous evidence has shown that stromal cell-derived inducing activity (SDIA), produced by the mouse PA6 stromal cell line, promotes dopaminergic differentiation of mouse, monkey and human embryonic stem cells in vitro. To examine whether PA6 stromal cells can enhance the yield of dopaminergic differentiation from neural progenitors, we generated neurospheres from embryonic day 11.5 (E11.5) (midb

The added value of ECG-gating for the diagnosis of myocardial infarction using myocardial perfusion scintigraphy and artificial neural networks

To assess the value of ECG-gating for the diagnosis of myocardial infarction using myocardial perfusion scintigraphy (MPS) and an artificial neural network. A total of 422 patients referred for MPS were studied using a one day Tc-99m-tetrofosmin protocol. Adenosine stress combined with submaximal dynamic exercise was used. The images were interpreted by one of three experienced clinicians and thes

Sensitivity of African biomes to changes in the precipitation regime

Aim Africa is identified by the Inter-governmental Panel on Climate Change (IPCC) as the least studied continent in terms of ecosystem dynamics and climate variability. The aim of this study was (1) to adapt the Lund-Postdam-Jena-GUESS (LPJ-GUESS) ecological modelling framework to Africa by providing new parameter values for tropical plant functional types (PFT), and (2) to assess the sensitivity

Risk preferences regarding multiple fatalities and some implications for societal risk decision making-an empirical study

Risk preferences related to accidents or other situations involving the possibility of multiple fatalities were studied in 87 persons in Sweden belonging to two separate groups with professional or educational knowledge of risk- and crisis-management issues. Use was made of a tradeoff method, the results obtained consisting of von Neuman-Morgenstern utility functions over the range of 0-1000 fatal

On Hieracium incurrens (Asteraceae) and similar species in central Sweden.

Hieracium incurrens Saelan ex Norrl., originally described from Finland, has been reported from Sweden several times and independently by different authors. Still, however, its presence in Sweden has remained dubious and it has become obvious that the different reports are referable to different taxa and the name has thus been, at least partially, misapplied. In the present study, all Swedish mate