Entwicklungspädagogik als Projektarbeit

Im vorliegenden Beitrag wird eine spezifische Form entwicklungspädagogischen Vorgehens vorgestellt. In einem ersten Teil wird erklärt, was man unter "Projektarbeit" versteht. In einem zweiten werden praktische Erfahrungen berichtet. Bemerkenswert ist der Hinweis, daß Projektarbeit auch außerschulisch möglich und sinnvoll ist. (DIPF/Orig.

Physiological and cell ultrastructure disturbances in wheat seedlings generated by Chenopodium murale hairy root exudate.

Chenopodium murale L. is an invasive weed species significantly interfering with wheat crop. However, the complete nature of its allelopathic influence on crops is not yet fully understood. In the present study, the focus is made on establishing the relation between plant morphophysiological changes and oxidative stress, induced by allelopathic extract. Phytotoxic medium of C. murale hairy root clone R5 reduced the germination rate (24% less than control value) of wheat cv. Nataša seeds, as well as seedling growth, diminishing shoot and root length significantly, decreased total chlorophyll content, and induced abnormal root gravitropism. The R5 treatment caused cellular structural abnormalities, reflecting on the root and leaf cell shape and organization. These abnormalities mostly included the increased number of mitochondria and reorganization of the vacuolar compartment, changes in nucleus shape, and chloroplast organization and distribution. The most significant structural changes were observed in cell wall in the form of amoeboid protrusions and folds leading to its irregular shape. These structural alterations were accompanied by an oxidative stress in tissues of treated wheat seedlings, reflected as increased level of H2O2 and other ROS molecules, an increase of radical scavenging capacity and total phenolic content. Accordingly, the retardation of wheat seedling growth by C. murale allelochemicals may represent a consequence of complex activity involving both cell structure alteration and physiological processes.This is a post-peer-review, pre-copyedit version of an article published in Protoplasma. The final authenticated version is available online at: [http://dx.doi.org/10.1007/s00709-018-1250-0

Acceptance tests in the process of agile software development

One of the key reasons for failures of information technology (IT) projects are the customer's unclear picture of the product and the constant changes of demands in the business world. Usually, in the early phases of project development the customer sees only a pale image of the desired final product. As the IT projects are inherently complex and time-consuming, new requirements often show up during the development process. Conventional development process starts with requirements analysis. When requirements are analyzed and written down, the software development is done in exact accordance with the detailed documentation. Agile models try to respond to the lack of flexibility in such cases and move software development closer to the rapidly changing costumer’s requirements. Test driven development and acceptance tests are the practices of extreme programming, an agile model of software development. The attention in test driven development has been mainly focused on the unit tests. This master thesis focuses to the acceptance tests. Acceptance tests are first compared to the unit tests. It has been concluded that differences relate to the properties that mainly concern people, who participate in the tests, the speed of execution and the integration with development tools. If both types of tests are considered as a test of certain program part, it can be concluded, that from a programmers perspective, acceptance test is actually a unit test without the term “smallest part” in its definition. In this regard, acceptance test are the “big” unit tests used to check on several interconnected units of the program at the highest level of test hierarchy. When it comes to the extreme programming, acceptance tests are moved to the initial stage of software development cycle and can therefore be used to drive the software development process and documentation. Test driven development with acceptance tests is regarded as one type of the software development process. The process presented uses test-driven development principles and acceptance tests to drive the development of requirements based on the user stories. The process presented here is being used in the development of website for the Statistical Office of Slovenia. First, the development tools for the implementation of the proposed process are presented. Later on, the principles of extreme programming and test-driven development with acceptance tests are used, in order to develop the website named Slovenian municipalities in numbers

Camelina (Camelina sativa (L.) Crantz) oilcake – untapped resource of phenolic compounds

The work includes a comprehensive study of phenolic compounds, their occurrence and identification in the residues after pressing of the oil from camelina seeds of Slovenian origin, i.e. oilcake. In addition, the efficiencies of antioxidant determinations using different methods according to different mechanisms are presented. These data demonstrate that almost all of the phenolic compounds in these seeds remain in the seed oilcake. The following antioxidants were confirmed: sinapine, 4-vinylphenol, 4-vinylguaiacol, 4-vinylsyringol, 4-vinylcatechol, ellagic acid, protocatechuic acid, <em>p</em>-hydroxybenzoic acid, sinapic acid, salicylic acid, catechin, quercetin and quercetin glucoside. The oilcake has high reducing power and radical scavenging activity. Heat treatment of seeds affects the amount of free, soluble and insoluble bound phenolic compounds as well as antioxidant capacity of individual fractions. Potential applications of camelina oilcake in the food industry are further justified by comparisons with other oilcakes and synthetic antioxidant

Development and optimisation of solid-phase extraction of extractable and bound phenolic acids in spelt (Triticum spelta L.) seeds

A solid-phase extraction (SPE) technique was developed and optimised for isolation and concentration of extractable and bound phenolic acids from germinated spelt seeds, for analysis by liquid chromatography–mass spectrometry. Samples initially underwent solvent extraction under different conditions to maximise the yield of phenolic antioxidants. Optimal extraction conditions for extractable phenolics were absolute methanol as solvent, sample-to-methanol ratio 1:9, and reconstitution in non-acidified water. The bound phenolics were extracted from sample pellets using hydrolysis with 2 M NaOH, acidification of the hydrolysate with formic acid, and simultaneous isolation and purification using Strata X polymeric RP tubes. Compared to liquid-liquid extraction, this direct SPE protocol has significant advantages in terms of higher extraction efficiencies of total and individual phenolics and their antioxidant activities. These data suggest that direct SPE represents a rapid and reliable method for quantitative analysis of both the extractable and the commonly overlooked bound phenolics in Triticum spelta seeds