Optical design of the Lyman alpha based beam emission spectroscopy(LAB)diagnostic on the HL-2A tokamak

In this article, we present the optical design of a novel diagnostic on the HL-2 A tokamak, i.e. the20-channel edge Lyman-alpha beam emission spectroscopy, which is a promising solution for edge density turbulence research on tokamaks, as it offers the possibility of density fluctuation measurement with a 3.3 mm spatial resolution while maintains a high temporal resolution of1 μs. The optical path, including the reflective collection optics, the high-dispersion spectrometer, and the linear detector array, is carefully optimized to obtain a good image quality and a high throughput. The maximum root mean square radius of the collection optics is 64 μm.The detected photon flux is estimated to be about 10~(11) photons/s/channel.     

Genetically modified starter and protective cultures

Modern approaches towards starter and protective culture improvement rely on advances in molecular biology. For most microorganisms used for food production, gene technological methods have been well developed. By recombinant DNA technology, ‘tailor-made’ starter and protective cultures may be constructed so as to combine technically desirable features. A single strain which normally would fail to accomplish a given ‘wtask’ may now be improved so as to meet a set of requirements necessary for a specific production or preservation process (e.g. wholesomeness, no off-flavour production, overproduction of bacteriocins or particular enzymes). In addition, undesirable properties (e.g. mycotoxin or antibiotic production by cheese moulds) may be eliminated by techniques such as ‘gene disruption’.     

Monitoring the linear alkylbenzene sulfonation process using high-temperature gas chromatography

Controlling the linear alkylbenzene sulfonate (LAS) sulfonation process is a critical part of the LAS manufacturing process; this process can be monitored by assaying for LAS content, unsulfonated linear alkylbenzene (LAB), and LAB sulfones. Traditionally, assaying the LAB and LAB sulfone contents has been time consuming and not straightforward. A simple and rapid procedure is described for the isolation and simultaneous capillary gas chromatographic (GC) quantification of LAB and LAB sulfones in LAS. The procedure involves extraction of the unsulfonated LAB and the LAB sulfones into n-heptane; sodium linear alkylbenzenesulfonate or linear alkylbenzenesulfonic acid (reacted to form sodium linear alkylbenzenesulfonate) remains in the aqueous extraction solvent layer. High-temperature capillary GC using a specialty metal capillary column enables both LAB and high molecular weight LAB sulfones to be quantified.     

Mathematical modelling of sound transmission loss performances of different coloured surfaces coated with polyurethane-based paint

ABSTRACT

The aim of this study is to investigate the effect of morphologies and the structure of polyurethane-based coatings created by different colour pigments, on sound transmission loss properties. To achieve this goal, coatings were created in different concentrations of 5%, 7% and 9% with red, green, orange and yellow pigments. The coatings were applied on glass surfaces and the sound transmission loss was measured by an experimental arrangement containing a microphone and a decibel meter. The effect of surface tension energy, surface roughness, reflection percentages and concentration of pigments were found to be negligible on the sound transmission loss, whereas the LAB colour codes have a determining effect. In the scope of this study, a new method and mathematical model were created to help measure the sound transmission loss on a surface, in which sound signal was carried with a laser beam via a system created in the laboratory.     

基于LAB色彩空间和DWT的数字水印算法

为了解决电子产品印刷盗版的问题,提出了基于LAB色彩空间和DW T的彩色图像数字水印算法。算法将水印置乱后嵌入到LAB色彩空间的亮度L分量的小波分解系数。实验证明,选择LAB色彩空间的亮度L分量比选择Y IQ色彩空间的Y分量嵌入水印具有更好的实验效果。所提出的算法对常用的图像处理如JPEG压缩、加噪、剪切和滤波等攻击具有较好的鲁棒性、不可见性和安全性。     

Safety assessment and antimicrobial properties of the lactic acid bacteria strains isolated from polish raw fermented meat products

Twenty-one strains of the genus Lactobacillus and the genus Pediococcus, isolated from Polish raw fermented meat products, were examined for the potential probiotic properties: resistance to simulated gastric and intestine conditions, safety assessment, and antimicrobial properties. Strains were resistant to gastric enzymes and low pH (3–6 log CFU/mL decrease) and intestinal enzymes and bile salts (1–3 log CFU/mL decrease). Most strains were resistant to gentamycin, streptomycin, vancomycin, tetracycline, ciprofloxacin, and kanamycin. Three of them (Lb. brevis BAL1, BAL10, and KL5) produced β-glucuronidase, which excludes them from qualifying as safe. Seven strains had the ability to produce bacteriocins or bacteriocin-like substances. Overall, strains Lb. brevis SCH6, Pd. pentosaceus BAL6, and KL14 revealed selected superior characteristics (resistance to the gastrointestinal conditions, safety assessment, and antimicrobial properties) as compared to the other LAB strains investigated, which made them a viable bioprotective culture that can be inoculated in raw fermented meat products as starter cultures.     

Bacteriocin producing Enterococcus faecalis isolated from chicken gastrointestinal tract originating from Phitsanulok,Thailand: Isolation,screening, safety evaluation and probiotic properties

A total of 230 isolates of lactic acid bacteria were isolated from gastrointestinal tracts (GIT) of indigenous chickens purchased from local market in Bang Rakam district, Phitsanulok, Thailand. Among 230 isolates, only 7 isolates, named CM6CR07, CM6CR11, CF1GI15, CF1GI14, CF1GI17-1, CF1GI17-2 and CF1GI 19 showed an inhibition zone against indicator strains. Bacteriocin activity was completely inactivated when Neutralized Cell Free Supernatants (NCFS) of the isolates were treated with proteases, confirming the proteinaceous nature of the bacteriocin component. NCFS of all selected bacteriocin producing lactic acid bacteria (SBP-LAB) retained their bacteriocin activity after heating at 100 °C for 30 min. All of SBP-LAB were identified as Enterococcus faecalis. These Ent. faecalis isolates harbored the same virulence genes. All strains were positive for gelE (gelatinase), efaA_fs (cell wall adhesins), hyl (hyaluronidase), ace (adhesin of collagen protein), cylL_L (cytolysin structural subunit) and cylL_S (cytolysin structural subunit) and were negative for asa1 (aggregation substance), agg (aggregation protein involved in adherence to eukaryotic cells), and esp (enterococcal surface protein). These Ent. faecalis showed a wide range of inhibitory spectrum against food-spoilage and food-borne pathogens when studied by agar spot test. The CFS and NCFS also inhibited some of food-spoilage and food-borne pathogenic indicator strains when checked by agar well diffusion assay. All of these Ent. faecalis survived simulated stomach conditions, whereas all of them could survive in conditions of simulated intestinal juice.     

A survey on the milk chemical and microbiological quality in dairy donkey farms located in NorthWestern Italy

There is a growing interest in donkey's milk as food for sensitive consumers, such as infants with cow's milk protein allergy and elderly people. The aim of this study was to carry out a survey on the dairy donkeys farming in Piedmont, Italy. The research was conducted in order to analyze the farm characteristics as well as the chemical and microbiological quality of milk. All the farms were small-sized, family-run, and, in most cases, animals were farmed semi-extensively. The donkey milk from Piedmont farms was characterized by a protein content around 1.5 g/100 mL and a fat content lower than 0.1 g/100 mL. Lysozyme activity was considerably higher than that reported in raw cow milk. The milk microbiological profile greatly differed among the farms. Milk sampled in the farm that performed hand milking showed total viable counts significantly lower than milk collected in the farms equipped with automatic milking. Samples were tested for several pathogens and negative results were observed, except for the detection of Bacillus cereus in one sample. The survey provided useful data for the laying down of recent regional regulation for the production and commercialization of donkey's milk. The results of the survey indicate that further research is needed in order to define the best management and nutritional strategies for the improvement of the quali-quantitative production of dairy donkeys.     

Injury Mechanisms of Lactic Acid Bacteria Starter Cultures During Spray Drying: A Review

Lactic acid bacteria (LAB) starter cultures can be processed by many drying techniques, among which spray drying has great potential. However, injuries of LAB during spray drying lead to a low survival rate. The microbial injuries of LAB during spray drying are specifically induced by dehydration inactivation, thermal inactivation, and balance between the two. To reduce the drying temperature, new drying techniques based on spray drying were tried; that is, low-temperature vacuum–spray drying and spray–freeze drying.     

乳酸菌能量代谢的蛋白质组学研究进展

乳酸茵凭借其悠久的历史、显明的特征及与人类生活紧密相关的特点受到了生物界和医学界的广泛关注。近年来,利用蛋白质组学对其进行研究的成果层出不穷。概述了乳酸菌能量代谢的蛋白质组学研究进展,并讨论了代谢路径之间的相互关系。