Schutz ökologisch sensibler Fließgewässer: Konzepte und Fallbeispiele

European rivers are subject to heavy demand. In this regard, hydromorphological alterations in connection with energy production or flood protection measures are among the most serious issues. Today only very few natural or near-natural river reaches remain, and in Austria only 15% of the rivers are classified as being in “very good” and a further 22% percent as being in “good” ecological condition. In keeping with the objectives of the EU Water Framework Directive, the National River Basin Management Plan defines measures intended to achieve a good ecological status and/or avoid the further deterioration of Austria’s waterbodies.     

Rapid urease screening of Yersinia on CIN agar plates

Yersinia enterocolitica is an important foodborne pathogen, but isolation of virulent Yersinia from food sources is still time consuming and requires skills. In this article, we describe a rapid urease screening on cefsulodin-irgasan-novobiocin (CIN) agar plates with an agar overlay assay. This test is simple to perform, all colonies on a plate can be checked simultaneously, it only takes minutes for detection of urease-positive colonies and the colonies survive for transfer, further characterisation, and storage. Additionally, this method is useful to isolate virulent (urease-positive and pYV harbouring) Y. enterocolitica from foodstuffs.     

Lessons from probiotic-host interaction studies in murine models of experimental colitis

In inflammatory bowel diseases (IBD), it is known that besides genetic and environmental factors (e.g. diet, drugs, stress), the microbiota play an important role in the pathogenesis. Patients with IBD have an altered microbiota (dysbiosis) and therefore, probiotics, defined as 'live micro-organisms that when administered in adequate amounts can confer a health benefit on the host', have been suggested as nutritional supplements to restore these imbalances. The best response on probiotics among the different types of IBD appears to be in the case of ulcerative colitis. Although probiotics show promise in IBD in both clinical and animal studies, further mechanistic studies are necessary to optimize the use of probiotics as supporting therapy in IBD. Murine models of experimental colitis have been used for decades to study this pathology, and these models have been proven useful to search for new therapeutic approaches. The purpose of this review is to summarize probiotic-host interaction studies in murine models of experimental colitis and to evaluate how these models can further help in understanding these complex interactions. Unraveling the molecular mechanisms behind the beneficial effects will assist in better and possibly more efficient probiotic formulations.     

Flow shop scheduling with flexible processing times

OR Spectrum - In numerous flow shop variants, the processing times of the operations are not fixed in advance, but may be distributed with some flexibility among the machines. In this paper, we...     

电池部分放电后析气量低的新型锌粉

用于碱性锌锰电池的锌粉在投产前都必须测定析气量,通常将使用的锌粉制成ＬＲ１４ 电池,采用２Ω恒电阻连续放电４ ．５ｈ 后在７０ ℃下贮存７ｄ ,如果锌粉释放出的气体量不高于负极集流体端部密封圈防爆孔开启压力的１０ ％ ～２０ ％ ,则该锌粉就可以使用。然而,有些合金锌粉在电池部分放电（ 如放电４０ｍｉｎ） 后析气量剧增,为了研究锌粉的析气行为,我们测试了不同规格电池和锌粉在电池部分放电后的析气量,结果显示,Ｇｒｉｌｌｏ 公司研制的一种新型锌粉在电池部分放电后析气量非常低,文章讨论了该锌粉的析气量和放电行为。     

Yttrium Silicate Coatings on Chemical Vapor Deposition-SiC-Precoated C/C–SiC: Thermodynamic Assessment and High-Temperature Investigation

Yttrium silicates are promising materials for improved oxidation and erosion protection for carbon fiber-reinforced composites. A two-layer coating system of low-pressure plasma-sprayed yttrium silicate on chemical vapor deposition-SiC-precoated C/C–SiC was tested under atmospheric re-entry conditions simulated within a plasma wind tunnel test facility. The thermal expansion behavior of Y₂SiO₅ and Y₂Si₂O₇ was investigated. The chemical compatibility with and without increasing oxygen partial pressure at the interface of the two-layer system was calculated by the CALPHAD method. The calculations were compared with experimental results. Furthermore, a thermodynamic explanation is presented to understand and predict the observed coating failure mechanism, identified as blister formation.     

Reproduction and Urine Marking in Laboratory Groups of Female Common Voles Microtus arvalis

In laboratory groups of common voles, Microtus arvalis, consisting of one mother, two of her daughters and one male, mainly the mother reproduced. The three females spent most of the time in close body contact. By using a modified method of coloring the urine of the three females by nonmetabolizable, nontoxic dyes, we found that mothers display a higher urine marking intensity than their daughters, and urine marks from the mother were distributed more frequently than those from the daughters. The results suggest that both pheromonal and behavioral mechanisms are involved in the regulation of reproduction in matriarchal groups of common voles.     

Flash welding and the testing of shafts

Abstract

This paper describes investigations carried out on a manually operated flash welder, including quality control by mechanical and ultrasonic testing.