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The breathing technique is a determining factor for the singer's sound quality and consequently crucial for the choral sound. However, very little is known about possible influences of the conductor's preparatory gesture on the way choral singers inhale before the beginning of a piece (respectively every subsequent phrase). The conducting literature does not discriminate between out- and inward preparatory gestures and even describes them as equivalent, but previous studies suggest that singers assign different types of inhalation to different preparatory gestures. It may therefore be assumed that the type of preparatory gesture has a direct influence on the singer's inhalation and tone production, and the aim of this study is hence to examine possible effects of two contrasting preparatory gestures on the singer's inhalation type and the resulting tone quality.In our within-subjects study design, 18 healthy choral singers (9 male/ 9 female) were recruited to participate in a laboratory experiment. The participants were asked to sing a tone suitable for their voice register in response to different video stimuli. These consisted of two conducting-videos, each showing a different preparatory gesture, and two control conditions with an animated bar and an arrow indicating the desired breathing type. The singers reacted to 10 sets of videos, each set consisting of the four stimuli in randomized order. For evaluation of the breathing behavior and vocal output during the different experimental conditions, chest wall kinematics of upper rib cage, abdominal rib cage and abdomen were measured via 3D motion capture and voice samples were recorded. The obtained data were filtered and compared using the repeated measures analysis of variance and post hoc Tukey test for significant results. The level of significance was set at P0.05.The results of the study show significant differences in volume of the abdomen between the two different gestures (FIn contrast to the existing conducting literature, which does not discriminate between out- and inward preparatory gestures, the results of this study show that the conductor's choice of trajectory direction and form of the preparatory gestures elicit spontaneous, gesture-specific reactions in singers' breathing behavior as well as the corresponding loudness and sound quality.

Summary Objective The breathing technique is a determining factor for the sound quality of the singers’ vocal production and thus crucial for the choral sound. The aim of this study was to examine choral singers’ awareness of breathing techniques and habits while singing and to identify potential correlations between the breathing technique and the preparatory gestures of the conductor. Methods In our prospective, quasi-experimental study, 720 choral singers answered a 25-item anonymous online survey which focused on demographic information, musical and choral experience, information on choir (size, type, repertoire) and conductor (age, gender, level of expertise). As the central issue we examined the subjects’ general knowledge of breathing techniques and habits and their own use thereof in choral practice. Finally, subjects were asked to watch videos showing two different preparatory conducting gestures and to assess the meaning of these gestures. Results The results of the study show that the majority of choral singers (68.1%) inhale not before and not after, but during the conductor's preparatory gesture. The most well-known (94.7%) and allegedly most frequently (81.8%) used type of inhalation is abdominal breathing. Six times more singers associate abdominal breathing with an outward gesture rather than with the more frequently occurring inward-upward gesture. Conclusion The conducting literature does not discriminate between out- and inward preparatory gestures and describe them as equivalent. However, according to our data, a vast majority of singers assign these gestures to different types of inhalation which influences singing technique and sound quality. This might lead to ambiguous action-reaction expectations from singers and conductors in rehearsals and concerts.

The performances of two novel aerogel based catalysts on the production of renewable diesel were compared with an impregnated catalyst for the deoxygenation of undiluted soybean oil. The catalysts were extensively characterized. The aerogel catalysts exhibited a remarkably higher production of hydrocarbons with a reaction rate over 4 times that of the impregnated catalyst and selectivity to uncracked hydrocarbon in excess of 90%. All catalysts exhibited zero order behavior in the undiluted condition tested and no deactivation was detected. The specific acidity appears to be directly linked to the degree of cracking achieved by the catalyst, with the impregnated catalyst being both the most acid and exhibiting the higher degree of cracking, thus lowering its selectivity. The subcritically dried aerogel catalyst had the best overall performance, exhibiting low levels of cracking and high selectivity to larger hydrocarbons, which has been linked to smaller crystallites and higher specific area.

An improved kinetic model for the deoxygenation of fatty acids was developed and compared with previously developed models. The models were compared using data collected from the deoxygenation of oleic acid using a novel, extensively characterized aerogel-based catalyst and previously published data of the deoxygenation of stearic acid, resulting in an extensive analysis ranging from 275 °C to 400 °C. The novel model was able to predict the behavior of reactants, intermediates and products for all cases analyzed in this paper. Akaike and Bayesian information criterions were applied, concluding that the novel kinetic model was indeed the best model to predict the behavior of both our original data and a previously published dataset. Relevant data regarding reaction rates and selectivity for the novel catalyst was given, showing a clear practical use of the results presented in this paper for the design and optimization of deoxygenation reactors.

An alternative to non-renewable fuels is the production of green diesel from deoxygenation of vegetable oils. In this study, the effect of the supports on nickel phosphide catalysts for deoxygenation of oleic acid to produce hydrocarbons was investigated. Nickel phosphide catalysts supported on USY, H-ZSM-5 and Al-SBA-15 were synthetized by temperature programmed reduction (TPR) of metal phosphate precursors and the prepared catalysts were characterized by atomic absorption spectroscopy (AAS), X-ray diffraction (XRD), small angle X-ray scattering (SAXS), temperature programmed reduction of hydrogen (TPR), nitrogen physisorption, temperature programmed desorption of ammonia (TPD), transmission electron microscopy (TEM) and Fourier-transform infrared spectroscopy (FTIR). The catalytic tests were performed in an autoclave batch reactor at 260 °C, 280 °C and 300 °C and 50 bar of hydrogen. The production of hydrocarbons (C10-C18) at 300 °C followed the order: Ni2P/Al-SBA-15 > Ni2P/H-ZSM-5 > Ni2P/USY. The Ni2P/Al-SBA-15 exhibited a remarkable deoxygenation activity, compared to noble metals. All the catalysts achieved more C17 than C18 hydrocarbons, therefore, decarbonylation/decarboxylation reactions prevail. With regard the temperature effect, the amount of hydrocarbons increased from 260 °C to 280 °C but it decreased from 280 °C to 300 °C for all catalysts, which can be ascribed to catalyst deactivation.

Low haematocrit values are generally well tolerated in terms of oxygen transport but a low haematocrit might interfere with blood coagulation. We thus sampled 60 ml of blood in 30 healthy volunteers. The blood was centrifuged for 30 min at 2000 g and separated into plasma, which contained the platelet fraction, and packed red blood cells. The blood was subsequently reconstituted by combining the entire plasma fraction with a mixture of packed red blood cells, 0.9% saline, so that the final haematocrit was either 40, 30, 20, or 10%. Blood coagulation was assessed by computerized Thrombelastograph® analysis. Data were compared using repeated measures analysis of variance and post‐hoc paired t‐tests with Bonferroni correction. Decreasing the haematocrit from 40 to 10% resulted in a shortening of reaction time (r) and coagulation time (k), and an increase in angle α, maximum amplitude (MA) and clot strength (G) (all P

To gain insight into the regulatory mechanisms of collagen VI synthesis we have characterized the cis-acting elements of the chicken alpha 1(VI) collagen promoter. Footprinting experiments with nuclear extracts from chicken embryos revealed three distinct elements, designated A, B, and C, that were protected from DNase I digestion. The nuclear proteins that interact with the three sites were identified by gel retardation assays in combination with the use of various oligonucleotide competitors as well as specific antibodies raised against well characterized transcription factors. Site A was found to be a target for transcriptional activator AP1, whereas sites B and C were shown to be recognized each by two distinct nuclear proteins which belong to the Sp1 multigene family. To address the question whether the three sites alone are able to direct transcription, a minipromoter construct was created in which the sequences of sites A, B, and C were placed in front of a reporter gene. After transfection into chicken fibroblasts, this construct exhibited a high relative promoter activity when compared to a large genomic fragment containing the basic alpha 1(VI) collagen promoter. Thus, the three sites are sufficient to induce transcription of this gene.

S U N D A Y 311 Selective Exclusion of High Titer Donor Plasma and Immunoadsorption Chromatography As Steps to Reduce Isoagglutinin Titers in IVIG Liane Hoefferer, Ibrahim El Menyawi, Brigitte Siani, Martin Imboden, Annette Gaida, Isabelle Glauser, Reinhard Bolli, Katharina Willimann, Sandra Wymann, A. Adriano Marques, Eleanora Widmer; CSL Behring, Berne, Switzerland. RATIONALE: Hemolysis is a rare but potentially serious complication of high-dose IVIG therapy. Isoagglutinins originating in donor plasma are believed to play a major role in these reactions, but host factors are also important. We determined the effects of excluding plasma from donors with high isoagglutinin titers from the pools used to prepare IVIG, and of specific anti-A/B immunoaffinity chromatography (IAC), on the anti-A and anti-B titers of IVIG products prepared using the process for Privigen/ Hizentra. METHODS: A high-throughput assay was used to identify plasma donors with the highest anti-A titers. The effects of addition of IAC with A/Btrisaccharide-coupled resins into the manufacturing process were also studied. Anti-A/B isoagglutinin titers in the resulting IVIG preparations were measured by indirect agglutination and flow cytometry. RESULTS: Exclusion of the 5% of plasma donors with the highest anti-A titers reduced both anti-A and anti-B isoagglutinins in the final product by approx. 50% (a single 2-fold dilution step, i.e. reduction of the titer from 1:16 to 1:8, and 1:8 to 1:4, respectively. N530 lots). Specific IAC reduced anti-A and anti-B titers by at least two 2-fold dilution steps in the final product (>80% reduction shown by flow cytometry on standard red cells), while the content of antibodies against common microbial antigens remained unchanged. CONCLUSIONS: Anti-A/B isoagglutinin reduction in IVIG products is feasible using screening and exclusion of a small percentage of high anti-A titer donors andwith specific IAC. These approachesmay reduce the risk of hemolysis in IgG therapy.