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Knowledge cores in large formal contexts
(2022-04-20)
Knowledge computation tasks, such as computing a base of valid implications, are often infeasible for large data sets. This is in particular true when deriving canonical bases in formal concept analysis (FCA). Therefore, it is necessary to find techniques that on the one hand reduce the data set size, but on the other hand preserve enough structure to extract useful knowledge. Many successful methods are based on random processes to reduce the size of the investigated data set. This, however, makes them hardly ...
Aufsatz
Synthesis of Geminal Bis- and Tetrakisphosphonate Ester Derivatives and Their Coordination Behavior Towards Ca(II) Ions
(2022-04-05)
Geminal Bisphosphonate (BP) Esters in Ca(II) Ion Coordination. A series of geminal BPs was prepared starting from their corresponding ethyl- or isopropyl (arylmethylene)phosphonate ester precursors. Complexation with CaCl₂ yields the derived coordination compounds [Ca(H₂O)₂(L1–L3)₂]Cl₂ or [Ca(L8)Cl₂]ₙ. Their structures in the solid- (SCXRD) as well as solution-state (¹H DOSY NMR) are evaluated and comprehensively compared to literature data.
The preparation and thorough characterization of a variety of (arylmethy ...
Aufsatz
Application of mixed-effects modelling and rule-based models to explain copper variation in soil profiles of southern Germany
(2022-05-25)
Copper (Cu) is an essential element for plants and microorganisms and at larger concentrations a toxic pollutant. A number of factors controlling Cu dynamics have been reported, but information on quantitative relationships is scarce. We aimed to (i) quantitatively describe and predict soil Cu concentrations (CuAR) in aqua regia considering site-specific effects and effects of pH, soil organic carbon (SOC) and cation exchange capacity (CEC), and (ii) study the suitability of mixed-effects modelling and rule-based ...
Aufsatz
Ausbrüche von Histomonose bei langsamer wachsenden Putenlinien
(2021-09-02)
Histomonosis or Blackhead Disease is a poultry disease caused by infection with the protozoan parasite Histomonas meleagridis. Outbreaks are most frequent in turkey flocks, with often high mortality rates of up to 100%. During a study with three slower growing turkey strains on an organic farm in the years 2015 to 2018, in all three fattening batches outbreaks of histomonosis occured. The disease was diagnosed histologically by PAS-staining, in some cases PCR detection was performed. Heterakis gallinarum could not ...
Aufsatz
Impact of Cropping Pattern and Climatic Parameters in Lower Chenab Canal System - Case Study from Punjab Pakistan
(2022-05-17)
In Pakistan, groundwater resources are depleting at an alarming rate due to intensive pumping, shifting of cropping patterns, and climate change vulnerability. The present study is aimed at investigating groundwater stress in the command area of Lower Chenab Canal (LCC) and associated branch canals. Groundwater stress is determined by considering the cropping patterns, surface water availability, groundwater levels, climatic variation, and crop water requirement (CWR) in the LCC command area. The climatic data is ...
Aufsatz
Liquid Silicone Rubber Foamed with Thermoplastic Expandable Microspheres
(2022-05-25)
To reduce the material costs as well as the density of Liquid Silicone Rubber (LSR), LSR foams can be produced in an injection molding process. Expandable thermoplastic microspheres can be used as blowing agents. This publication deals with the analysis of the cell structure of these LSR foams. For this purpose, cylindrical disks are injection molded and examined for their cell structure as a function of different proportions of microspheres using a scanning electron spectroscope. In addition, the density of the ...
Aufsatz
Feed digestibility, digesta passage and faecal microbial biomass in desert-adapted goats exposed to mild water restriction
(2021-07-18)
In arid and semi-arid environments, extensively managed ruminants regularly experience drinking water shortage, especially in the dry season. The present study therefore investigated the effects of mild drinking water restriction on feed intake, feed digestibility, solid digesta passage and composition of faeces including faecal microbial biomass. A feeding trial was conducted in Oman, during the dry summer months.
Nine adult male Batinah goats were subjected to three watering regimes in a 3 × 3 Latin Square design. ...
Aufsatz
Millimetre scale aeration of the rhizosphere and drilosphere
(2022-06-22)
Soil aeration is a critical factor for oxygen-limited subsoil processes, as transport by diffusion and advection is restricted by the long distance to the free atmosphere. Oxygen transport into the soil matrix is highly dependent on its connectivity to larger pore channels like earthworm and root colonised biopores. Here we hypothesize that the soil matrix around biopores represents different connectivity depending on biopore genesis and actual coloniser. We analysed the soil pore system of undisturbed soil core ...
Aufsatz
Using heuristic worked examples to promote solving of reality-based tasks in mathematics in lower secondary school
(2022-04-19)
This study examined whether learning with heuristic worked examples can improve students’ competency in solving reality-based tasks in mathematics (mathematical modeling competency). We randomly assigned 134 students in Grade 5 and 180 students in Grade 7 to one of three conditions: control condition (students worked on reality-based tasks), worked example condition (students studied worked examples representing a realistic process of problem-solving by fictitious students negotiating solutions to the tasks), and ...
Aufsatz
Gender Representations Elicited by the Gender Star Form
(2022-02-28)
In many languages, masculine language forms are not only used to designate the male gender but also to operate in a generic fashion. This dual function has been found to lead to male biased representations when people encounter the generic masculine. In German, the now predominant substitute is the gender star form (e.g., Athlet*innen). In two experiments, we examined gender representations elicited when reading the gender star form (vs. generic masculine vs. pair forms). We found that, following the generic masculine, ...