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Styrene emulsion polymerization was performed in batch reactor using Raman spectroscopy for in situ monitoring of styrene conversion. The variation of the band of trigonal aromatic ring breathing at 1,000 cm−1 was analyzed in detail as a function of monomer conversion (wavenumber, integrated intensity, and half‐width at half‐maximum). The observed variation was described both qualitatively and quantitatively by a model assuming that the overall signal resulted from the addition of two close and distinct Gaussian signals, one originating from the monomer and the other one from the polymer repeat units. A reliable estimation of monomer conversion was obtained using the relative contributions of both components. The results were comparable to those obtained using the ratio of integrated intensities of the band at 1,000 cm−1 (overlapping signals of monomer and polymer) and the band at 1,631 cm−1 (signal specific to monomer). It was shown experimentally that information about monomer conversion could be obtained by applying linear model mixture to a single band of Raman spectrum, which provided an alternative method to the use of a ratio of integrated intensities. [ABSTRACT FROM AUTHOR]

Styrene emulsion polymerization was performed in batch reactor using Raman spectroscopy for in situ monitoring of styrene conversion. The variation of the band of trigonal aromatic ring breathing at 1,000 cm−1 was analyzed in detail as a function of monomer conversion (wavenumber, integrated intensity, and half‐width at half‐maximum). The observed variation was described both qualitatively and quantitatively by a model assuming that the overall signal resulted from the addition of two close and distinct Gaussian signals, one originating from the monomer and the other one from the polymer repeat units. A reliable estimation of monomer conversion was obtained using the relative contributions of both components. The results were comparable to those obtained using the ratio of integrated intensities of the band at 1,000 cm−1 (overlapping signals of monomer and polymer) and the band at 1,631 cm−1 (signal specific to monomer). It was shown experimentally that information about monomer conversion could be obtained by applying linear model mixture to a single band of Raman spectrum, which provided an alternative method to the use of a ratio of integrated intensities. [ABSTRACT FROM AUTHOR]

O bjectives To investigate possible interactions visible on electroencephalogram recordings caused by concomitant administration of marbofloxacin and carprofen or cimicoxib in dogs without central nervous system disease. M ethods Totally 21 client-owned dogs undergoing different surgeries were included in a randomised, blinded, clinical study. Each dog was assigned to one of two groups treated with either carprofen or cimicoxib pre- and postoperatively. After anaesthetic induction both groups received marbofloxacin intravenously while recording an electroencephalogram. Offline electroencephalogram analysis included qualitative evaluation and Fast Fourier Transformation. Postoperative analgesia was evaluated for 24 hours and after 10 days with the short-form Glasgow Composite Measure Pain Scale. Statistical analysis included Wilcoxon signed rank test, Mann-Whitney U test and Student's t-test with α set at 5%. R esults Marbofloxacin injection caused no effects on quantitative and qualitative electroencephalogram parameters in both groups. No differences in postoperative pain scoring were found between treatment groups. C linical S ignificance Concurrent use of marbofloxacin with either cimicoxib or carprofen did not induce neuroexcitatory activities in dogs without CNS disease directly after administration. [ABSTRACT FROM AUTHOR]

Reasons for performing study: Post operative ileus (POI) in horses is a severe complication after colic surgery. A commonly used prokinetic drug is lidocaine, which has been shown to have stimulatory effects on intestinal motility. The cellular mechanisms through which lidocaine affects smooth muscle activity are not yet known. Objectives: To examine the effects of lidocaine on smooth muscle in vitro and identify mechanisms by which it may affect the contractility of intestinal smooth muscle. Hypothesis: Ischaemia and reperfusion associated with intestinal strangulation can cause smooth muscle injury. Consequently, muscle cell functionality and contractile performance is decreased. Lidocaine can improve basic cell functions and thereby muscle cell contractility especially in ischaemia-reperfusion-challenged smooth muscle. Methods: To examine the effects of lidocaine on smooth muscle function directly, isometric force performance was measured in vitro in noninjured and in vivo ischaemia-reperfusion injured smooth muscle tissues. Dose-dependent response of lidocaine was measured in both samples. To assess membrane permeability as a marker of basic cell function, release of creatine kinase (CK) was measured by in vitro incubations. Results: Lidocaine-stimulated contractility of ischaemia-reperfusion injured smooth muscle was more pronounced than that of noninjured smooth muscle. A 3-phasic dose-dependency was observed with an initial recovery of contractility especially in ischaemia-reperfusion injured smooth muscle followed by a plateau phase where contractility was maintained over a broad concentration range. CK release was decreased by lidocaine. Conclusion: Lidocaine may improve smooth muscle contractility and basic cell function by cellular repair mechanisms which are still unknown. Improving contractility of smooth muscle after ischaemia-reperfusion injury is essential in recovery of propulsive intestinal motility. Potential relevance: Characterisation of the cellular mechanisms of effects of lidocaine, especially on ischaemia-reperfusion injured smooth muscle, may lead to improved treatment strategies for horses with POI. [ABSTRACT FROM AUTHOR]

Behavioural and electrophysiological responses ofAnopheles gambiaeGilessensustricto (Diptera: Culicidae) to human skin emanations collected on glass beads were studied using a dual-port olfactometer and electroantannography. Glass beads to which skin emanations from human hands had been transferred elicited a level of attraction similar to a human hand. The attractiveness of these handled glass beads faded away 4 h after transfer onto the beads. Storage at−20°C for up to 8 weeks showed a decreased but still attractive effect of the beads. In a choice test between one individual and four others, the emanations from the reference individual were significantly more attractive in three out of four cases. The headspace of handled glass beads elicited a dose-dependent EAG response. The substances causing EAG activity could be removed partially by dichloromethane, ethanol and pentane-ether. Glass beads provide a suitable neutral substrate for the transfer of human odour to enable chemical analysis of the human skin emanations for identification of kairomones of anthropophilic mosquitoes. [ABSTRACT FROM AUTHOR]

We studied the effects of food supplementation with ; synonym HANSEN CBS 5926; 1 g per day for 9 days) on the presence and co-localization patterns of neuronal markers in myenteric neurones of the pig jejunum. The pan neuronal marker Hu revealed no change in the number of neuronal cell bodies per ganglion (37 ± 7 in control vs 34 ± 9 in the group). Ranked by size the following cell populations were identified: choline acetyltransferase (ChAT), calbindin-28k (CALB), substance P (SP), neurofilament 160 kD (NF-160), vasoactive intestinal polypeptide (VIP), nitric oxide synthase (NOS), calcitonin gene-related peptide (CGRP), calretinin (CALRET). We found a significant decrease in the number of CALB myenteric neurones in animals which received supplemented diet. None of the other neuronal markers revealed any difference between controls and treated animals. The study reports transmitter-localization patterns in the myenteric plexus of the pig jejunum and provides evidence that changes in the neurochemistry of enteric neurones occur with supplemented diet. Although only CALB expression was altered and the functional significance of this finding remains unknown, our study identified a possible new effector level of probiotics in the gut. [ABSTRACT FROM AUTHOR]

Examines the flow patterns and mixing conditions of the composite materials on the single-screw extruder Buss Cokneader. Development of the Newtonian fluids; Measurement of residence time distribution; Use of the carbon black particles.

Knowledge of the neurochemicaI coding of submucosal neurones in the human gut is important to assess neuronal changes under pathological conditions. We therefore investigated transmitter colocalization patterns in rectal submucosal neurones in normal tissue (n = 11) and in noninflamed tissue of Crohn's disease (CD) patients (n=17). Neuronespecific enolase (NSE), choline acetyltransferase (CHAT), vasoactive intestinal polypeptide (VIP), substance P (SP), nitric oxide synthase (NOS) and calcitonin gene-related peptide (CGRP) were detected immunohistochemically in whole-mount preparations from rectal biopsies. The neuronal marker NSE revealed no differences in the number of cells per ganglion (controls 5.0; CD 5.1). Four cell populations with distinct neurochemical codes were identified. The sizes of the populations ChAT/VIP (58% vs. 55%), ChAT/SP (8% vs. 8%), and CHAT/- (22% vs. 22%) were similar in control and CD. The population VIP/was significantly increased in CD (12% vs. 2% in controls). Unlike in controls, all NOS neurones colocalized ChAT in CD. Thickened CGRP-fibres occurred in CD. We identified neurochemically distinct populations in the human submucous plexus. The increase in the VIP/-population, extensive colocalization of ChAT and NOS and hypertrophied CGRP fibres indicated adaptive changes in the enteric nervous system in noninflamed rectum of CD patients. [ABSTRACT FROM AUTHOR]