Two-dimensional imaging of OH and CH intermediates in a premixed flame using natural gas bunsen burner by means of laser induced fluorescence techinique are described. A tunable laser beam with a ...single laser pulse energy of 1.5mJ is focused by a cylindrical concave lens, which forms laser sheet 5mm high and 0.5mm thick. We have chosen a band near 308nm : OH X2Π(υ=0)→A2Σ(υ=0) excitation and a band near 431nm : CH X2Π(υ=0)→A2Δ(υ=0) excitation. Fluoresence at a right angle is amplified by gated image intensifier and detected by CCD camera. A complete picture of qualitative distribution of OH and CH is obtained by combining several piuctures taken at a series of diffrent distances between the bumer head and laser sheet.
Raman induced polarization spectroscopy (RIPS) is developed as a new technique for the analysis of reactive flow systems such as combustion. RIPS is a time-domain spectroscopy that may be used to ...measure temperature and concentration of chemical species with sub-picosecond resolution. After a brief overview of the RIPS process, an analytical expression for the signal is derived in the semi-classical limit to determine its temperature dependence. Spectra for nitrogen are presented that were recorded using an oven at temperatures up to 1320 K. Theoretical fits to the spectra are produced and used to extract rotational temperatures. The observed RIPS temperatures agree to within about 5% of values recorded by a thermocouple. Improvements to the current scheme are proposed for increasing the accuracy of the temperature measurements. A homebuilt femtosecond (fs) Ti:sapphire laser system is used to conduct the experiments and its design is discussed in detail. The laser produces 1.4 W of 800 nm output at 3.3 kHz. Pulse durations of 50 fs are obtained routinely. Femtosecond pulses are produced in a self-mode-locked oscillator and amplified using the chirped-pulse amplification technique. A regenerative amplifier is pumped by a homebuilt, intra-cavity doubled Nd:YAG laser that produces 20 W of 532 nm output at 3.3 kHz. Drawings and specifications of the oscillator, pulse stretcher, amplifier, pump laser, and pulse compressor are provided, in addition to the procedure followed to build and operate each of these units.
The nematode Caenorhabditis elegans is a popular model system in genetics, not least because a majority of human disease genes are conserved in C. elegans. To generate a comprehensive inventory of ...its expressed proteome, we performed extensive shotgun proteomics and identified more than half of all predicted C. elegans proteins. This allowed us to confirm and extend genome annotations, characterize the role of operons in C. elegans, and semiquantitatively infer abundance levels for thousands of proteins. Furthermore, for the first time to our knowledge, we were able to compare two animal proteomes (C. elegans and Drosophila melanogaster). We found that the abundances of orthologous proteins in metazoans correlate remarkably well, better than protein abundance versus transcript abundance within each organism or transcript abundances across organisms; this suggests that changes in transcript abundance may have been partially offset during evolution by opposing changes in protein abundance.
Abstract Osteogenic agents, such as bone morphogenetic protein-2 (BMP-2), can stimulate the degradation as well as the formation of bone. Hence, they could impair the osteoconductivity of ...functionalized implant surfaces. We assessed the effects of BMP-2 and its mode of delivery on the osteoconductivity of dental implants with either a naked titanium surface or a calcium-phosphate-coated one. The naked titanium surface bore adsorbed BMP-2, whilst the coated one bore incorporated, adsorbed, or incorporated and adsorbed BMP-2. The implants were inserted into the maxillae of adult miniature pigs. The volume of bone deposited within a defined “osteoconductive” (peri-implant) space, and bone coverage of the implant surface delimiting this space, were estimated morphometrically 1–3 weeks later. After 3 weeks, the volume of bone deposited within the osteoconductive space was highest for coated and uncoated implants bearing no BMP-2, followed by coated implants bearing incorporated BMP-2; it was lowest for coated implants bearing only adsorbed BMP-2. Bone-interface coverage was highest for coated implants bearing no BMP-2, followed by coated implants bearing either incorporated, or incorporated and adsorbed BMP-2; it was lowest for uncoated implants bearing adsorbed BMP-2. Hence, the osteoconductivity of implant surfaces can be significantly modulated by BMP-2 and its mode of delivery.
Background and aim
Loss of time is a major obstacle to efficient stroke treatment. Our telestroke path intends to optimize prehospital triage using a video link connecting ambulance personnel and a ...stroke physician. The objectives were as follows: (1) To identify patients suffering a stroke and (2) in particular large vessel occlusion (LVO) strokes as candidates for endovascular treatment. We have chosen the Rapid Arterial Occlusion Evaluation (RACE) scale for this purpose.
Methods
This analysis aimed to verify the feasibility of prehospital stroke identification by video assessment. In this prospective telestroke cohort study, we included 97 subjects, in which the RACE score (items: facial palsy, arm and leg motor function, head and gaze deviation, and aphasia or agnosia) was applied, and the assessment videotaped by a trained member of the Emergency Medical Services (EMS) in the field using a mobile device. Each recorded patient video was independently assessed by three experienced stroke physicians from a certified stroke center and compared to the neuroimaging gold standard. Within this feasibility study, the stroke code was not altered by the outcome of the RACE assessment, and all patients underwent the standard procedures within the emergency unit.
Results
We analyzed 97 patients (median age 78 years, 53% women), of whom 51 (52.6%) suffered an acute stroke, 12 (23.5%) of which were due to an LVO and 46 patients had symptoms mimicking a stroke. The sensitivity of stroke identification was 77.8%, and specificity was 53.6%. In regard to the identification of an LVO, sensitivity was 69.4% and specificity was 84.3%. The inter-rater agreement in the RACE-score assessment was ICC = 0.82 (intraclass-correlation coefficient).
Conclusion
These results confirm our hypothesis that the local telestroke concept is feasible. It allows correct (i) stroke and (ii) LVO identification in the majority of the cases and thus has the potential to assist in efficient prehospital triage.
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