Effect of Pectinmethylesterase Infusion Methods and Processing Techniques on Strawberry Firmness

Strawberry halves were pretreated with fungal pectinmethylesterase (PME) and calcium chloride using, respectively, passive osmotic infusion, vacuum‐assisted infusion, and pressure‐assisted infusion with the aim to improve the firmness. The vacuum‐assisted procedure was observed to be the only method able to accomplish an uptake of infusion solution and hence capable of improving the firmness of the strawberries. Significantly less firmness increase was realized when tomato PME was vacuum‐infused instead of fungal PME. Strawberry halves were pretreated by vacuum‐assisted infusion with fungal PME and calcium chloride and were subsequently subjected to thermal treatments at 60 °C and 80 °C and pressure treatments at about 400 MPa and 550 MPa. For all treatments studied, the pretreated sample was significantly firmer compared with the reference sample. For the thermal processes, the residual firmness relative to the initial value before treatment was depending on the temperature of the treatment and not on the pretreatment. However, vacuum‐assisted infusion of PME and calcium could limit the portion of firmness loss due to pressure treatment to 30% compared with 80% for non‐pretreated fruits.     

Phenotypic variations of muscle fibre and intramuscular fat traits in Longissimus muscle of F(2) population Duroc×Berlin Miniature Pig and relationships to meat quality

In Longissimus muscle from a F(2) population of Duroc×Berlin Miniature Pigs, micro-structural fibre traits and fatty acid composition were investigated to calculate correlation coefficients between these traits and meat quality. The animals of the F(2) population exhibited low carcass weight (55.7±11.2 kg), low meat percentage (35.0±8.4%) but a relatively high intramuscular fat content (3.52±1.44%) compared to pure bred animals (F(0)). No unacceptable meat quality was observed. The variation coefficients of carcass composition, muscle fibre traits, and fat traits were high enough to allow the analysis of candidate genes which influence the growth of muscle fibres, fat cells, and meat quality. Phenotypic correlation coefficients between muscle fibre characteristics and meat quality traits were low whereas fatty acid composition and meat quality were more closely related. The correlation coefficients between muscle fibre traits and fatty acid composition ranged from 0.10 to 0.40. The relationship between a low quotient of n-6/n-3 fatty acids in muscle and greater fibre sizes, higher percentages of the oxidative fibre type and higher capillary density was noteworthy indicating good conditions for muscle growth and meat quality.     

先进低成本的铸件浇注和补缩系统设计方法

用实例介绍了一项用于铸造生产的三维模拟技术,通过对金属液充型和凝固过程的数值模拟进行铸造工艺设计,从而在计算机上实现可视铸造过程,能保证既快又省地设计一个优化的铸造工艺.与传统的模数法,经验和试错的工艺设计不同,本模型是用铸件的凝固时间计算补缩系统.从一个铸件凝固模拟开始,根据凝固时间和被补缩的体积,计算冒口和冒口颈的尺寸和数量,再进行铸件加冒口的模拟计算,做必要的修正,直到获得满意的结果,最后根据铸件的临界壁厚、体积、充型速度和浇注温度等参数计算浇注系统.当整个系统设计完成后,模拟计算整个充型和凝固过程以验证设计,做必要的修正,直到获得一个能生产无铸造缺陷铸件的铸造工艺,即保证一次成功生产出合格铸件,节约了时间和成本.     

Beyond the fascination of online-games: Probing addictive behavior and depression in the world of online-gaming

This study examined problematic gaming behavior and depressive tendencies among people who play different types of online-games. Other game-related variables were investigated to determine if other differences between three game types could be established. Participants in the current research (n = 468) can be classified into three independent groups. Subjected users either solely played massive multiplayer online role-playing games (MMORPGs) or they preferred online-ego-shooters (OES) or real-time-strategy games (RTS). Results indicate that MMORPG users show more often problematic gaming behavior, depressive tendencies and lower self-esteem compared to users playing other online-games. MMORPG users reported to playing significantly more often in order to escape from real-life problems, which might be a valuable coping strategy but might also lead to problematic gaming behavior.     

基于多流多状态动态贝叶斯网络的音视频连续语音识别

语音和唇部运动的异步性是多模态融合语音识别的关键问题,该文首先引入一个多流异步动态贝叶斯网络(MS-ADBN)模型,在词的级别上描述了音频流和视频流的异步性,音视频流都采用了词-音素的层次结构.而多流多状态异步DBN(MM-ADBN)模型是MS-ADBN模型的扩展,音视频流都采用了词-音素-状态的层次结构.本质上,MS-ADBN是一个整词模型,而MM-ADBN模型是一个音素模型,适用于大词汇量连续语音识别.实验结果表明：基于连续音视频数据库,在纯净语音环境下,MM-ADBN比MS-ADBN模型和多流HMM识别率分别提高35.91%和9.97%.     

Optimal adaptive control of (bio)chemical reactors: past, present and future

In this paper an overview of optimal adaptive control of (bio)chemical reactors is presented. Following the paradigm of the Minimum Principle of Pontryagin the derivation of optimal control sequences for fed-batch production processes is briefly revisited. Next, it is illustrated how the obtained optimal profiles can be exploited in the characterization of nearly optimal control sequences in terms of the qualitative behavior of the specific growth and production rates as function of the limiting substrates. Implementing this knowledge leads in a natural way to the design of (nearly) optimal adaptive feedback controllers. Special emphasis will lie on the potential of on-line biomass measurements (obtained with the Biomass Monitor) in the estimation algorithm of the growth kinetics being the adaptive component of the controller. Extensions towards fermentation processes with (i) multiple substrates and (ii) non-monotonic kinetics are also included. Finally, perspectives towards optimal adaptive control of not perfectly mixed (bio)chemical reactor systems, such as chemical tubular reactors, are outlined.     

Untersuchung der Funktion von Leichtflüssigkeitsabscheidern bei Verwendung von Kraftstoffen mit unterschiedlichen FAME-Zusätzen

The use of biogenic additives in fuels is required by law for environmental reasons. This raises the question of whether the oil separator tested according to ÖNORM EN 858-1 complies with these new requirements. In this study, a commercial mineral oil separator was tested with different fuels with up to 100?% biodiesel (FAME) and its elimination performance was described in terms of the parameters KW, KW-Index DIN EN ISO 9377-2 H 53 (2000), and also the non-standardized parameters for mineral oil analysis in accordance with H 18 and H 53 without the purification stage. The results showed that all the tests with different fuel mixtures complied with the test value of 5 mg/l laid out in EN 858-1 (2005) and based on the parameter mineral oil analysis in accordance with DIN 38409-H 18 (1981). As the purification stage of this method removes the biofuel fraction, the question arises as to whether fuels with increased biogenic content can be analyzed satisfactorily using these standardized mineral oil parameters; and whether the use of pure mineral oil for ÖNORM EN 858-1 (2005) performance tests is still suitable, or whether other fuels should also be used as test media.     

Effect of de-methylesterification on network development and nature of Ca-pectin gels: Towards understanding structure-function relations of pectin

Pectins of varying degree and pattern of methylesterification were produced through controlled de-esterification of highly esterified citrus pectin, using carrot pectin methylesterase (PME) (P-pectins), Aspergillus aculeatus PME (F-pectins) or sodium hydroxide saponification (C-pectins). Estimation of the degree of methylesterification (DM) and quantification of the pattern of methylester distribution in terms of absolute degree of blockiness (DB_abs) enabled the characterisation of pectins. Characterised pectins were used for the preparation of Ca²⁺-pectin gels with varying calcium ion (Ca²⁺) concentration. The rheological characteristics of produced gels were evaluated by means of small-amplitude oscillatory tests. During gel formation, gel strength was monitored so as to allow assessment of network development. Based on the evaluation of mechanical spectra, the nature of the cured gels was established. Depending on Ca²⁺ concentration as well as DM and DB_abs, gels prepared from specific C-pectins (48 ≥ DM ≥ 26%; 9 ≤ DB_abs ≤ 37%) and F-pectins (64 ≥ DM ≥ 29%; 9 ≤ DB_abs ≤ 50%) showed a striking decrease of the gel strength with time, while gel networks produced from other pectins either displayed a continuous increase of the gel strength or verged towards pseudo-equilibrium within the observation time of 5 h. Furthermore, the DM, DB_abs and Ca²⁺ concentration influenced the evolution of Ca²⁺-pectin networks from “structured liquids” to “strong gels”. Based on the experimental results, specific mechanisms of Ca²⁺ interactions with pectins were (also) considered.