Does a cycle training course improve cycling skills in children?

Introduction

The aim of this study was to determine the short-term effects of cycle training on basic cycling skills in children from the 4th grade of elementary school. Furthermore, the influence of gender, socio-economic status (SES) and initial cycling skills level on the effects of the cycle training was investigated.

Methods

Five participating schools were randomly assigned to the intervention (n = 3) or control condition (n = 2). Children's cycling skills were assessed, using a practical cycling test, at baseline and immediately after the intervention. At baseline, all participating children received a short parental questionnaire on child's demographic and family factors. After the pre-test, cycle training took place only in the intervention schools. Repeated measure analyses were conducted to evaluate the effectiveness of the cycle training.

Results

The cycle training had a statistically significant effect on children's total cycling skill (F = 46.9, p < 0.001). On mounting the bicycle and start to cycle (F = 2.6, p = 0.11), cycling one handed (F = 2.0, p = 0.16), and cycling on a sloping surface (F = 1.5, p = 0.23), no statistically significant effects were detected. On all other cycling skills, time × condition interaction effects were statistically significant. Gender, SES and initial cycling skills level had no significant influence on the effects of the cycle training.

Conclusion

This study showed that a cycle training of only three sessions was effective to improve children's cycling skills at short term and that cycle training within a traffic-free environment seems to be a useful first step in the development of safe cycling behaviors.     

Evidence for Behavioral Attractiveness of Methoxylated Aromatics in a Dynastid Scarab Beetle-Pollinated Araceae

Many plants attract their pollinators with floral scents, and these olfactory signals are especially important at night, when visual signals become inefficient. Dynastid scarab beetles are a speciose group of night-active pollinators, and several plants pollinated by these insects have methoxylated aromatic compounds in their scents. However, there is a large gap in our knowledge regarding the compounds responsible for beetle attraction. We used chemical analytical analyses to determine temporal patterns of scent emission and the composition of scent released from inflorescences of Philodendron selloum. The attractiveness of the main components in the scent to the dynastid scarab beetle Erioscelis emarginata, the exclusive pollinator of this plant, was assessed in field biotests. The amount of scent increased rapidly in the evening, and large amounts of scent were released during the activity time of the beetle pollinators. Inflorescences emitted a high number of compounds of different biosynthetic origin, among them both uncommon and also widespread flower scents. Methoxylated aromatic compounds dominated the scent, and 4-methoxystyrene, the most abundant compound, attracted E. emarginata beetles. Other compounds, such as (Z)-jasmone and possibly also the methoxylated aromatic compound 3,4-dimethoxystyrene increased the attractiveness of 4-methoxystyrene. Methoxylated aromatics, which are known from other dynastid pollinated plants as well, are important signals in many scarab beetles in a different context (e.g., pheromones), thus suggesting that these plants exploit pre-existing preferences of the beetles for attracting this group of insects as pollinators.     

Removal of diatrizoate with catalytically active membranes incorporating microbially produced palladium nanoparticles

There is an increasing concern about the fate of iodinated contrast media (ICM) in the environment. Limited removal efficiencies of currently applied techniques such as advanced oxidation processes require more performant strategies. The aim of this study was to establish an innovative degradation process for diatrizoate, a highly recalcitrant ICM, by using biogenic Pd nanoparticles as free suspension or immobilized in polyvinylidene fluoride (PVDF) and polysulfone (PSf) membranes. As measured by HPLC-UV, the removal of 20 mg L⁻¹ diatrizoate by a 10 mg L⁻¹ Pd suspension was completed after 4 h at a pH of 10. LC-MS analysis provided evidence for the sequential hydrodeiodination of diatrizoate. Pd did not lose its activity after incorporation in the PVDF and PSf matrix and the highest activity (k_cat = 30.0 ± 0.4 h⁻¹ L g⁻¹ Pd) was obtained with a casting solution of 10% PSf and 500 mg L⁻¹ Pd. Subsequently, water containing 20 mg L⁻¹ diatrizoate was treated in a membrane contactor, in which the water was supplied at one side of the membrane while hydrogen was provided at the other side. In a fed batch configuration, a removal efficiency of 77% after a time period of 48 h was obtained. This work showed that membrane contactors with encapsulated biogenic nanoparticles can be instrumental for treatment of water contaminated with diatrizoate.     

Working chute behavior of feedlot cattle can be an indication of cattle temperament and beef carcass composition and quality

The relationship between working chute temperament and beef carcass quality traits were measured on 183 crossbred feedlot steers. Steers were weighed and sorted into 16 pens and weighed every 28 days. Temperament was evaluated as exit velocity (EV), chute score (CS), and catch score (CAPS). Tissue samples were collected for DNA profile including docility (IGENITY^®, Merial Limited, Duluth, GA, USA). Steers were harvested at 14 to 16 months of age (606 ± 52 kg). Exit velocity increased and CS and CAPS values declined over time. Steers receiving a lower CAPS score had more marbling (P = 0.02). Ribeye steaks from steers with a slow first recorded EV were more tender (P = 0.02) than steaks from faster EV steers. IGENITY^® docility index had a positive (P = 0.09) correlation (r = 0.15) with Warner–Bratzler shear force (WBS) indicating a higher docility index was loosely associated with tougher meat.     

Anti-homogalacturonan antibodies: A way to explore the effect of processing on pectin in fruits and vegetables?

The potential of the anti-homogalacturonan(HG) antibodies JIM5, JIM7, LM7, LM18, LM19, LM20 and PAM1 for investigating the effect of processing on pectin in fruit and vegetable tissues was screened in this study. In this respect, the specificity of the antibodies towards pectin and methoxylated polygalacturonic acid with defined degrees and patterns of methylesterification was elaborated, leading to a substantial extension of the information already available in literature. Based on the obtained specificities, the distribution of pectin methylesterification in carrot and broccoli tissue was mapped. It was established that pectin with a low degree of esterification (DE) and a more blockwise distribution of the methylesters is, both in carrot and in broccoli, preferentially located at the tricellular junctions between adjacent cells. This cell wall region, however, is also likely to contain other structural pectic domains. The inner face of the cell wall adjacent to the plasma membrane seems to contain pectin with a medium DE. To evaluate the potential of the anti-HG antibodies to detect changes in degree and pattern of methylesterification caused by processing, carrot and broccoli were subjected to a thermal treatment aimed to stimulate the endogenous pectinmethylesterase (PME) activity. It was revealed that process-induced de-esterification by endogenous PME mainly tends to take place at discrete regions of the inner face of the cell wall adjacent to the plasma membrane for carrot and in tricellular junctions and the middle lamella for broccoli.     

Polarographische bestimmung von Diacetyl und Acetoin in butter

Zusammenfassung Diacetyl wird durch Wasserdampfdestillation aus dem Probenmaterial isoliert und in Acetatpuffer, pH 5,2 polarographisch mit dem Differential-Puls-Verfahren bestimmt. Acetoin wird durch Oxidation mit FeCl₃ in Diacetyl überführt und in gleicher Weise bestimmt.

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The polarographic determination of Diacetyl and Acetoin in butter

Summary Diacetyl is isolated from butter by steamdestillation and determined in acetate-buffer, pH 5,2, by differential-pulse-polarography. Acetoin ist oxidized to Diacetyl with FeCl₃ and then determined as described.

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Herrn Prof. Dr. Ing. Friedrich Asselmeyer zur Vollendung des 70. Lebensjahres gewidmet     

Efficacy of ultraviolet radiation as an alternative technology to inactivate microorganisms in grape juices and wines

Since sulphur dioxide (SO₂) is associated with health risks, the wine industry endeavours to reduce SO₂ levels in wines with new innovative techniques. The aim of this study was, therefore, to investigate the efficacy of ultraviolet radiation (UV)-C (254 nm) as an alternative technology to inactivate microorganisms in grape juices and wines.A pilot-scale UV-C technology (SurePure, South Africa) consisting of an UV-C germicidal lamp (100 W output; 30 W UV-C output) was used to apply UV-C dosages ranging from 0 to 3672 J l⁻¹, at a constant flow rate of 4000 l h⁻¹ (Re > 7500). Yeasts, lactic and acetic acid bacteria were singly and co-inoculated into 20 l batches of Chenin blanc juice, Shiraz juice, Chardonnay wine and Pinotage wine, respectively. A dosage of 3672 J l⁻¹, resulted in an average log₁₀ microbial reduction of 4.97 and 4.89 in Chardonnay and Pinotage, respectively. In Chenin blanc and Shiraz juice, an average log₁₀ reduction of 4.48 and 4.25 was obtained, respectively.UV-C efficacy may be influenced by liquid properties such as colour and turbidity. These results had clearly indicated significant (p < 0.05) germicidal effect against wine-specific microorganisms; hence, UV-C radiation may stabilize grape juice and wine microbiologically in conjunction with reduced SO₂ levels.     

Effect of Salt and Liver/Fat Ratio on Viscoelastic Properties of Liver Paste and Its Intermediates

The effect of salt and liver/fat ratio on the viscoelastic characteristics of liver paste and its intermediates (liver batter and liver paste batter) were evaluated by applying dynamic oscillatory tests in order to obtain detailed insight into the structural organisation of those products and how the characteristics of the intermediates are related to those of the end product. Liver paste batters were prepared at liver/fat ratios of 35/35 (w/w) and 20/50 (w/w). Salt was added at 0 and 1.8 % at each ratio. Stress sweeps and frequency sweeps were executed to characterise the viscoelastic properties of liver batter, liver paste batter and liver paste. Both intermediates and liver paste were characterised as weak gel-like emulsions with G′ greater than G″. G′ and G″ of liver paste were higher in magnitude compared with both intermediates due to structure building during pasteurisation and cooling. Generally, the values of the viscoelastic parameters of liver paste batter and liver paste increased with the addition of salt. With salt, a stronger and more stable liver paste was obtained. This effect may be attributed to solubilisation of salt soluble proteins, making more liver proteins available to act as emulsifier. However, salt affected the viscoelastic properties of liver batter in the opposite way: a weaker structure was formed with salt. A higher liver/fat ratio (35/35 versus 20/50) only increased the viscoelastic properties of liver paste batter while liver paste was not affected. This is probably due to the crystallisation of the fat in the liver paste with a high fat/liver ratio, which besides the liver proteins, also aid to structure building of liver paste. However, a higher liver/fat ratio did increase the critical stress (σ _c) in both liver paste batter and liver paste with the formation of a more stable structure.