Einarbeitung als Qualifizierungsphase : Bindeglied zwischen Ausbildung und institutionalisierter Weiterbildung

"Der Beitrag analysiert am Beispiel junger Fachkräfte, die nach Abschluß ihrer betrieblichen Ausbildung adäquat beschäftigt sind, den qualifikatorischen Stellenwert, den die Einarbeitung in den ersten Berufsjahren im Kontext von Ausbildung und institutionalisierter Weiterbildung hat. Im einzelnen wird folgenden Fragen nachgegangen: - Welches Gewicht, welchen Anteil hat die Einarbeitungsphase bei der Entwicklung der beruflichen Handlungskompetenz? - Welche Qualifikationen werden durch Einarbeitung ausgeprägt? Was wird durch Einarbeitung gelernt? Wie, in welchen Lernformen vollzieht sich die Qualifizierung in der beruflichen Einstiegsphase? - Welche Bedingungen fördern (oder hemmen) das Lernen im Arbeitsprozeß? - Welche Bedeutung wird einer Gestaltung der Einarbeitungsphase nach Lerngesichtspunkten seitens der Betriebe zugemessen? Plädiert für wird eine bewußte Gestaltung der Einarbeitungsphase nach lernfördernden Kriterien! Einarbeitung ersetzt dabei keinen formalen Ausbildungsabschluß. Zu überlegen ist allerdings, ob das Lernfeld 'Arbeitsplatz' unter Lerngesichtspunkten nicht auch so gestaltet werden kann, daß 'lernungewohnte' Personengruppen, die mit schulischen Lernformen Schwierigkeiten haben, zu einem formalen Abschluß geführt werden können. Grundlage des Beitrags sind Ergebnisse des Forschungsprojekts 'Qualifizierung in den ersten Berufsjahren' des Bundesinstituts für Berufsbildung. Die empirische Basis bilden Erhebungen bei Berufsanfängern (repräsentative Stichproben unter Erwerbstätigen mit Abschluß einer betrieblichen Ausbildung), vertiefende Fallstudien/leitfadenstrukturierte Interviews mit Berufsanfängern und betrieblichen Umfeldpersonen, eine Analyse von Stellenanzeigen sowie eine Untersuchung von betrieblichen Modellen zur Weiterqualifizierung junger Fachkräfte." (Autorenreferat)Einarbeitung, Qualifizierung, betriebliche Berufsausbildung, Ausbildungsabsolventen, Lernort, Berufserfahrung, Personalpolitik

Können Umweltchemikalien durch Interferenz mit endokrinen Funktionen (endocrine disruptors) zur Verweiblichung führen? - Ökotoxikologische Untersuchungen von Wasserproben aus Baden-Württemberg auf Amphibien

Umweltchemikalien, die nach ökotoxikologischen Gesichtspunkten bisher als unbedenklich galten, können hormonähnliche Wirkungen entfalten. Diese sogenannten "endocrine disruptors" stören die normalen hormongesteuerten Abläufe im Körper und da ihre bisher beobachteten Effekte in den verschiedenen Vertebratenklassen hauptsächlich auf östrogenartigen Wirkungen beruhten, wurden all diese Phänomene unter dem Begriff der "Verweiblichung" zusammengefaßt. Ziel des hier vorgestellten Forschungsvorhabens ist es mit Amphibien als Studienmodell zu klären, ob in Baden-Württemberg die Gewässerbelastung mit Umweltchemikalien zum Phänomen der Verweiblichung führen kann, was auch ein Indikator für eine potentielle Gefährdung des Menschen wäre. Die Untersuchungen hierzu umfassen bei Xenopus laevis verschiedene Nachweisebenen zur östrogenen Potenz von Umweltchemikalien: (1) Nachweis der Bindung an den Östrogenrezeptor in der Leber, was die Voraussetzung für eine hormonähnliche Wirkung darstellt, (2) biologische Wirkung auf zellulärer Ebene durch Bestimmung der Vitellogeninsynthese in Hepatocyten-Primärzellkulturen, die durch Östrogene spezifisch induziert wird, und (3) Wirkung in vivo auf das Gesamttier mit Experimenten zum Nachweis der Induktion der Vitellogeninsynthese bei adulten Tieren und der Beeinflussung der Geschlechtsdifferenzierung bei der Kaulquappenentwicklung. Die Ergebnisse belegen mit Amphibien als Studienmodell die verschieden gute Eignung der 3 Nachweisebenen zur Bestimmung östrogenartiger Wirkungen. Recently several studies showed that environmental chemicals without toxical risks exhibit humoral effects. These so called "endocrine disruptors" disturb normal endocrine feed back mechanisms and mainly estrogenic effects were observed in all classes of vertebrates causing "feminization" phenomena. The aim of our present research using amphibians as a model is to study if environmental water pollution in Baden-Württemberg is able to cause feminization phenomena, which would also indicate a potential risk for humans. The assessment of estrogenic potencies of environmental chemicals includes several levels of investigation using the amphib Xenopus laevis: (1) binding of environmental chemicals to liver estrogen receptor, (2) biological significance at cellular level by assaying vitellogenin synthesis in primary cultured hepatocytes, and (3) in vivo effects on intact animals by experiments determining induction of vitellogenin synthesis in adult animals and influences of sexual determination during larval development. Our results indicate several suitabilities of all 3 levels of investigation for assessment of estrogenic effects using amphibs as model

Fish Feeds in Aquaponics and Beyond: A Novel Concept to Evaluate Protein Sources in Diets for Circular Multitrophic Food Production Systems

With the general objective of optimizing internal nutrient recycling, circular multitrophic food production systems, e.g., combining fish, plant, and insect larvae production, rely on the quality and composition of sustainable nutritional inputs. Therefore, differences in dissolved and solid nutrient excretion patterns produced by Nile tilapia (Oreochromis niloticus) reared in recirculating aquaculture systems (RAS) with 5% daily water exchange and fed black soldier fly meal (BSFM), poultry by-product meal (PM), poultry blood meal (PBM) and fish meal (FM) as single protein sources were investigated to evaluate the potential for creating specific fish meal-free diets. Fish fed the FM and PM diet showed the significantly best (p 0.05) growth performance (specific growth rate (SGR): 2.12 ± 0.04/2.05 ± 0.11; feed conversion ratio (FCR): 0.86 ± 0.03/0.92 ± 0.01), whereas the PBM diet caused significantly reduced performance (SGR: 1.30 ± 0.02; FCR: 1.79 ± 0.05) in comparison to the FM/PM diet as well as the BSF diet (SGR: 1.76 ± 0.07; FCR: 1.11 ± 0.05). The FM and PM diet resulted in a faster increase and significantly higher dissolved nitrogen and phosphorus levels, while the BSF diet caused faster accumulation and significantly elevated levels of dissolved potassium, magnesium, and copper. The PBM diet resulted in the feces with the significantly highest nutrient density (gross energy, crude protein, and amino acids) but overall much lower dissolved nutrient levels in the water. Results are discussed with regard to implications for developing circular multitrophic food production systems.Peer Reviewe

Toward Feeds for Circular Multitrophic Food Production Systems: Holistically Evaluating Growth Performance and Nutrient Excretion of African Catfish Fed Fish Meal-Free Diets in Comparison to Nile Tilapia

In aquaponics and circular multitrophic food production systems, dietary protein source, as well as fish species choice, particularly in cases of different nutritional physiology, could be factors affecting excreted nutrient profiles. Accordingly, growth performance, dissolved nutrient accumulation and feces nutrient profiles were evaluated for African catfish (Clarias gariepinus) reared in recirculating aquaculture systems (RAS) and fed single protein source diets based on black soldier fly larvae meal (BSF), poultry by-product meal (PM), poultry blood meal (PBM) and fish meal (FM) and the results were compared to previous findings for Nile tilapia (Oreochromis niloticus). All diets resulted in significantly different growth performances of African catfish, with FM producing the best growth performance, followed by PM, BSF and PBM. PM resulted in the highest soluble reactive phosphorus concentrations (SRP) in the RAS water; whereas, BSF resulted in the highest K, Mg and Cu concentrations. The highest feces nutrient density was recorded for PBM; whereas, FM and PM yielded the lowest feces nutrient density. Comparing African catfish to Nile tilapia revealed that the former showed significantly better growth performance with FM and PM, however, significantly weaker performance with BSF. Although dissolved K accumulation was similar between species across diets, significant differences were recorded for total inorganic nitrogen and SRP production per unit of feed for individual diets. Despite similar feces nutrient profiles, African catfish produce significantly less feces dry matter per unit of feed for each diet compared to Nile tilapia. Findings are discussed regarding their implications for aquafeed development in the context of circular multitrophic food production systems.the Federal Ministry of Education and Research/PtJ Project Management Agency as part of Agricultural Systems of the Future (CUBES Circle)Peer Reviewe

Urban Planning and Corona Spaces – Scales, Walls and COVID-19 Coincidences

This study focuses on the role and responsibility of urban planning in mitigating the COVID-19 pandemic ́s impact. The far-reaching social and economic consequences of this threat are counteracted by organisational and constructional measures to prevent lockdowns and finally illnesses and deaths. Corona spaces and voids are introduced as a consistent multi scale approach concerning the pandemics spatial implications and respective measures. These terms are operationalised for urban planning and can be used as an overarching concept to be communicated within cross-sectoral planning tasks. A comparison of Taiwan's and the USA's responses to the outbreak suggests that the coincidence at the beginning of a pandemic can be controlled by institutional precautions. On an urban scale, organisational measures (e.g. contact tracing, quarantine, and lockdown) can be supported by constructional ones concerning e.g. transport, public spaces, urban agriculture, and offices aimed at crowding reduction. If appropriate measures are applied, urban density does not seem to increase spreading the virus, whereby a regression analysis based on data of districts in Germany shows no relationship between population density and COVID-19 deaths. Lockdown prevention should be a planning goal and multifunctional approaches that integrate aspects of virus resilience should be favoured over the monothematic urban development approach (Leitbild) of a virus resilient city. Urban planning can contribute to the mitigation of future outbreaks by including pandemic preparedness in planning frameworks

Influence of Substrates on the Quality of Hermetia Meal for Fish Meal Substitution in Nile Tilapia Oreochromis niloticus

Commercially produced black soldier flies (Hermetia illucens) represent a promising fish meal substitute, particularly in the context of using agricultural by-products and waste. Here, the culture of Hermetia maggots on five selected substrates (potato protein (P) as a by-product of starch production, rapeseed oil cake (R) from rape oil production, maize silage (M), soybean (S) meal and, as a control, concentrated chicken feed (C)) were evaluated, assessing the growth performance of Hermetia maggots related to the overall production and the nutritional composition of the respective meal. Subsequently, their use as ingredients in aquafeed formulations was evaluated in a feeding trial with juvenile Nile tilapia Oreochromis niloticus, assessing the growth performance of the fish. Substrates used for Hermetia culture significantly affected the growth and development of the maggots, revealing substantial differences in the meal quality. Still, if incorporated in isonitrogenous and isocaloric diets (33% crude protein, 21–22 MJ/kg) replacing 75% of the fishmeal protein in the formulated diets, no significant differences in growth performance of the fish were observed compared to the fishmeal control. As a conclusion, substrates clearly affect the production yield and the composition of maggots. Nevertheless, this can be compensated by feed formulation as demonstrated by the feeding trial.Peer Reviewe

Können Umweltchemikalien zur Verweiblichung führen?

Umweltchemikalien, die nach ökotoxikologischen Gesichtspunkten bisher als unbedenklich galten, können hormonähnliche Wirkungen entfalten. Diese sogenannten "endocrine disruptors" stören die normalen hormongesteuerten Abläufe im Körper und da ihre bisher beobachteten Effekte in den verschiedenen Vertebratenklassen hauptsächlich auf östrogenartigen Wirkungen beruhten, wurden all diese Phänomene unter dem Begriff der "Verweiblichung" zusammengefaßt. Ziel des hier vorgestellten Forschungsvorhabens ist es mit Amphibien als Studienmodell zu klären, ob in Baden-Württemberg die Gewässerbelastung mit Umweltchemikalien zum Phänomen der Verweiblichung führen kann, was auch ein Indikator für eine potentielle Gefährdung des Menschen wäre. Die Untersuchungen hierzu umfassen bei Xenopus laevis verschiedene Nachweisebenen zur östrogenen Potenz von Umweltchemikalien: (1) Nachweis der Bindung an den Östrogenrezeptor in der Leber, was die Voraussetzung für eine hormonähnliche Wirkung darstellt, (2) biologische Wirkung auf zellulärer Ebene durch Bestimmung der Vitellogeninsynthese in Hepatocyten-Primärzellkulturen, die durch Östrogene spezifisch induziert wird, und (3) Wirkung in vivo auf das Gesamttier mit Experimenten zum Nachweis der nduktion der Vitellogeninsynthese bei adulten Tieren und der Beeinflussung der Geschlechtsdifferenzierung bei der Kaulquappenentwicklung. Die Ergebnisse belegen mit Amphibien als Studienmodell die verschieden gute Eignung der 3 Nachweisebenen zur Bestimmung östrogenartiger Wirkungen. Recently several studies showed that environmental chemicals without toxical risks exhibit humoral effects. These so called "endocrine disruptors" disturb normal endocrine feed back mechanisms and mainly estrogenic effects were observed in all classes of vertebrates causing "feminization" phenomena. The aim of our present research using amphibians as a model is to study if environmental water pollution in Baden-Württemberg is able to cause feminization phenomena, which would also indicate a potential risk for humans. The assessment of estrogenic potencies of environmental chemicals includes several levels of investigation using the amphib Xenopus laevis: (1) binding of environmental chemicals to liver estrogen receptor, (2) biological significance at cellular level by assaying vitellogenin synthesis in primary cultured hepatocytes, and (3) in vivo effects on intact animals by experiments determining induction of vitellogenin synthesis in adult animals and influences of sexual determination during larval development. Our results indicate several suitabilities of all 3 levels of investigation for assessment of estrogenic effects using amphibs as model

Bisphenol A induces superfeminization in the Ramshorn snail Marisa cornuarietis (Gastropoda: Prosobranchia) at environmentally relevant concentrations

Previous investigations have shown that bisphenol A (BPA) induces a superfeminization syndrome in the freshwater snail Marisa cornuarietis at concentrations as low as 1 μg/L. Superfemales are characterized by the formation of additional female organs, enlarged accessory sex glands, gross malformations of the pallial oviduct, and a stimulation of egg and clutch production, resulting in increased female mortality. However, these studies were challenged on the basis of incomplete experimentation. Therefore, the objective of the current approach was to bridge several gaps in knowledge by conducting additional experiments. In an initial series of experiments, study results from the reproductive phase of the snails were evaluated in the sub-micrograms per liter range. Before and after the spawning season, superfemale responses were observed [NOEC (no observed effect concentration) 7.9 ng/L, EC10 (effective concentration at 10%) 13.9 ng/L], which were absent during the spawning season. A further experiment investigated the temperature dependence of BPA responses by exposing snails at two temperatures in parallel. The adverse effect of BPA was at least partially masked at 27°C (EC10 998 ng/L) when compared with 20°C (EC10 14.8 ng/L). In M. cornuarietis, BPA acts as an estrogen receptor (ER) agonist, because effects were completely antagonized by a co-exposure to tamoxifen and Faslodex. Antiandrogenic effects of BPA, such as a significant decrease in penis length at 20°C, were also observed. Competitive receptor displacement experiments indicate the presence of androgen- and estrogen-specific binding sites. The affinity for BPA of the estrogen binding sites in M. cornuarietis is higher than that of the ER in aquatic vertebrates. The results emphasize that prosobranchs are affected by BPA at lower concentrations than are other wildlife groups, and the findings also highlight the importance of exposure conditions

Effects of BPA in snails : Oehlmann et al. respond

We welcome critical appraisals that help to provide balance; however, Dietrich et al. gave an unjustified reproach. We feel that Dietrich’s position is severely compromised because he serves as an expert for the bisphenol A (BPA) Industry Group (Brussels, Belgium). We would like to respond to the issues raised by Dietrich et al., as well as to their oversights and inappropriate interpretations of our findings..