3,578 research outputs found

    Was macht „gute“ BiologielehrkrĂ€fte aus?:Befragungen von Lehrenden in der Didaktik der Biologie und Biologie-Lehramtsstudierenden an deutschen Hochschulen

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    Im Projekt „Optimierung der Biologie-Lehramtsausbildung in gemeinsamer Anstrengung (OBLigAt)“ kommen Vorstellungen und Standpunkte von Biologie-Fachleitern, Biologiedidaktik-Dozenten an den Hochschulen, Biologie-Lehramtsstudierenden und -Referendaren zur Verbesserung der Ausbildung zum Ausdruck. Es werden die Ergebnisse von 79 Hochschuldozenten in der Didaktik der Biologie und von 442 Biologie-Lehramtsstudenten vorgestellt. Nach ihrer Meinung werden in den fachdidaktischen Studienanteilen viele Aspekte, die zu gutem Unterricht fĂŒhren sollen, gut bis befriedigend behandelt. GrundsĂ€tzlich werden hierbei die Bedeutung der BerĂŒcksichtigung von SchĂŒlervorstellungen erkannt sowie personale und diagnostische Kompetenzen ausgebildet. Diskrepanzen zwischen der Schwerpunktsetzung der Dozenten und den Vorstellungen der Studierenden liegen in der Forderung der Studierenden nach mehr praktischen Aspekten, die sich unmittelbar fĂŒr den Unterricht umsetzen lassen. Eine theoretische Fundierung als Basis der Unterrichtsgestaltung rĂŒckt eher fĂŒr Dozenten in den Vordergrund. Insgesamt ist die Kooperation zwischen Fachwissenschaft, Didaktik und PĂ€dagogik zu optimieren. Die Ergebnisse bieten Ansatzpunkte, die Ausbildung im Sinne des Projekts OBLigAt zu verbessern

    A statement by Scientists for Future concerning the protests for more climate protection

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    In March 2019, German-speaking scientists and scholars calling themselves Scientists for Future, published a statement in support of the youth protesters in Germany, Austria, and Switzerland (Fridays for Future, Klimastreik/Climate Strike), verifying the scientific evidence that the youth protestors refer to. In this article, they provide the full text of the statement, including the list of supporting facts (in both English and German) as well as an analysis of the results and impacts of the statement. Furthermore, they reflect on the challenges for scientists and scholars who feel a dual responsibility: on the one hand, to remain independent and politically neutral, and, on the other hand, to inform and warn societies of the dangers that lie ahead

    Investigation of early supplementation of nucleotides on the intestinal maturation of weaned piglets

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    Nucleotides are essential for the development of the gastrointestinal tract and immune function, but their intake with milk by piglets could be insufficient. The effect of nucleotides on growth and health was tested on 98 piglets divided into two groups: NU, orally administrated with 4 mL of a nucleotide-based product (SwineMOD¼ ) at 10, 15, 18, 21, 27 days, or not (CO). Blood and feces were sampled at weaning (26 d, T1), and at 38 d (T2). Per each group and time-point, eight piglets were slaughtered and jejunal Peyer’s patches (JPPs) were collected. NU increased hemoglobin content and hematocrit, but not growth. At weaning, the NU fecal microbiota was characterized by the abundance of Campylobacteraceae, more typical of the growing phase, compared to CO, with a greater abundance of Streptococcaceae. For the blood transcriptome, an initial greater inflammatory activation was seen in CO, while at T2, NU enriched gene sets related to erythropoiesis. The activation of gene groups ranging from epigenetic response to transcriptional regulation evidenced an intense proliferative activity in NU JPPs. NU supplementation did not influence the growth performance of piglets but could have expressed a positive effect on pig microbiota anticipating its maturation at weaning. This immunostimulant activity in the JPPs could moderate the inflammation in the immediate pre-weaning

    Impact of tumour volume and treatment delay on the outcome after linear accelerator-based fractionated stereotactic radiosurgery of uveal melanoma

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    Background/aims: Primary radiation therapy is used to treat malignant uveal melanoma (UM). We report our single-centre experience with fractionated radiosurgery (fSRS) with a linear accelerator (LINAC) after specific adaptation for small target volumes with HybridArc. Methods: From October 2014 to January 2020, 101 patients referred to Dessau City Hospital with unilateral UM underwent fSRS with 50 Gy given in five fractions on five consecutive days. Primary endpoints were local tumour control, globe preservation, metastasis and death. Potential prognostic features were analysed. Kaplan-Meier analysis, Cox proportional hazards model and linear models were used for calculations. Results: The median baseline tumour diameter was 10.0 mm (range, 3.0–20.0 mm), median tumour thickness 5.0 mm (range, 0.9–15.5 mm) and median gross tumour volume (GTV) 0.4 cm³ (range, 0.2–2.6 cm³). After a median follow-up of 32.0 months (range, 2.5–76.0 months), 7 patients (6.9%) underwent enucleation: 4 (4.0%) due to local recurrence and 3 (3.0%) due to radiation toxicities, and 6 patients (5.9%) revealed tumour persistence with a GTV exceeding 1.0 cm³. Of 20 patients (19.8%) who died, 8 (7.9%) were tumour-related deaths. Twelve patients (11.9%) suffered from distant metastasis. GTV showed an impact on all endpoints, and treatment delay was associated with reduced odds of eye preservation. Conclusion: LINAC-based fSRS with static conformal beams combined with dynamic conformal arcs and discrete intensity-modulated radiotherapy results in a high tumour control rate. The tumour volume is the most robust physical prognostic marker for local control and disease progression. Avoiding treatment delay improves outcomes

    The neglected liaison: Targeting cancer cell metabolic reprogramming modifies the composition of non‐malignant populations of the tumor microenvironment

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    Metabolic reprogramming is a well‐known hallmark of cancer, whereby the development of drugs that target cancer cell metabolism is gaining momentum. However, when establishing preclinical studies and clinical trials, it is often neglected that a tumor mass is a complex system in which cancer cells coexist and interact with several types of microenvironment populations, including endothelial cells, fibroblasts and immune cells. We are just starting to understand how such populations are affected by the metabolic changes occurring in a transformed cell and little is known about the impact of metabolism‐targeting drugs on the non‐malignant tumor components. Here we provide a general overview of the links between cancer cell metabolism and tumor microenvironment (TME), particularly focusing on the emerging literature reporting TME‐specific effects of metabolic therapies

    Land degradation assessment for sustainable soil management

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    Desertification is a complex phenomenon defined as the extreme degree of land degradation induced by human activities and climatic conditions. Climate change is accelerating and widening these areas. Previews analysis and studies assessed the vulnerability to desertification in Italy at national and regional level through a methodological approach based on integrating climate, soil, vege-tation, and socio-economic data (ESA). The studies carried out by ISPRA aim to provide an update of the of land degradation assessment in Italy, based on Trends.Earth methodology and of the three UN-SDGs sub-indicators on Target 15.3.1 (land use/land cover, land productivity and soil organic carbon above and below ground status and trends), together with additional dimensions of land degradation considered crucial for national land characters. Final assessment of the percentage of degraded land is around 36% of national area. This exercise demonstrates the importance to con-sider a larger number of data and include information on other fac-tors, such as climate, physical, chemical data. This integrated approach to the assessment of land degradation will allow to describe also of the loss of related ecosystem services

    Cells as active particles in asymmetric potentials: Motility under external gradients

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    Cell migration is a crucial event during development and in disease. Mechanical constraints and chemical gradients can contribute to the establishment of cell direction, but their respective roles remain poorly understood. Using a microfabricated topographical ratchet, we show that the nucleus dictates the direction of cell movement through mechanical guidance by its environment. We demonstrate that this direction can be tuned by combining the topographical ratchet with a biochemical gradient of fibronectin adhesion. We report competition and cooperation between the two external cues. We also quantitatively compare the measurements associated with the trajectory of a model that treats cells as fluctuating particles trapped in a periodic asymmetric potential. We show that the cell nucleus contributes to the strength of the trap, whereas cell protrusions guided by the adhesive gradients add a constant tunable bias to the direction of cell motion

    The swine waste resistome: Spreading and transfer of antibiotic resistance genes in Escherichia coli strains and the associated microbial communities

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    The overuse of antimicrobials in livestock farming has led to the development of resistant bacteria and the spread of antibiotic-resistant genes (ARGs) among animals. When manure containing these antibiotics is applied to agricultural fields, it creates a selective pressure that promotes the acquisition of ARGs by bacteria, primarily through horizontal gene transfer. Most research on ARGs focuses on their role in clinical antibiotic resistance and their transfer from environmental sources to bacteria associated with humans, such as Escherichia coli. . The study investigates the spread of antibiotic-resistant genes (ARGs) through class 1 integrons in 27 Escherichia coli strains from pig manure. It focuses on six common ARGs (ermB, erm B, cml A, flo R, qnr S, tet A, and TEM) and the class 1 integron gene, assessing their prevalence in manure samples from three pig farms. The study found correlations and anticorrelations among these genes, indicating a predisposition of the integron in spreading certain ARGs. Specifically, cmlA A and tetA A genes were positively correlated with each other and negatively with int1, suggesting they are not transferred via Int 1. Farm B had the highest int1 counts and a higher abundance of the TEM gene, but lower levels of cmlA A and tetA A genes. The results underscore the complexity of predicting ARG spread in agricultural environments and the associated health risks to humans through the food chain. The study's results offer valuable insights into the antibiotic-resistant genes (ARGs) profile in swine livestock, potentially aiding in the development of methods to trace ARGs in the environment

    Effect of different doses of camelina cake inclusion as a substitute of dietary soybean meal on growth performance and gut health of weaned pigs

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    Camelina cake (CAM) is a co-product proposed as an alternative protein source; however, piglet data are still limited. This study aimed to evaluate the effect of different doses of CAM in substitution of soyabean meal on the growth, health and gut health of weaned pigs. At 14 d post-weaning (d0), sixty-four piglets were assigned either to a standard diet or to a diet with 4 %, 8 % or 12 % of CAM. Piglets were weighed weekly. At d7 and d28, faeces were collected for microbiota and polyamine and blood for reactive oxygen metabolites (ROM) and thyroxine analysis. At d28, pigs were slaughtered, organs were weighed, pH was recorded on gut, colon was analysed for volatile fatty acids (VFA) and jejunum was used for morphological and gene expression analysis. Data analysis was carried out using a mixed model including diet, pen and litter as factors; linear and quadratic contrasts were tested. CAM linearly reduced the average daily gain from d0-d7, d0-d14, d0-d21 and d0-d28 (P <= 001). From d0-d7 increasing CAM linearly decreased feed intake (P = 004) and increased linearly the feed to gain (P = 0004). CAM increased linearly the liver weight (P < 00001) and affected the cadaverine (P < 0001). The diet did not affect the ROM, thyroxine, intestinal pH, VFA and morphology. All doses of CAM increased the alpha diversity indices at d28 (P < 005). CAM at 4 % promoted the abundance of Butyricicoccaceae_UCG-008. Feeding with CAM enhanced resilience in the gut microbiome and can be evaluated as a potential alternative protein source with dose-dependent limitations on piglet growth performance

    In ovo injection of a galacto-oligosaccharide prebiotic in broiler chickens submitted to heat-stress: Impact on transcriptomic profile and plasma immune parameters.

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    This study investigated the effects of a galactooligosaccharide (GOS) prebiotic in ovo injected on intestinal transcriptome and plasma immune parameters of broiler chickens kept under thermoneutral (TN) or heat stress (HS) conditions. Fertilized Ross 308 eggs were injected in ovo with 0.2 mL physiological saline without (control, CON) or with 3.5 mg of GOS (GOS). Three-hundred male chicks/injection treatment (25 birds/pen) were kept in TN or HS (30\ub0 C) conditions during the last growing phase, in a 2 x 2 factorial design. At slaughter, from 20 birds/injection group (half from TN and half from HS), jejunum and cecum were collected for transcriptome analysis, and plasma was collected. No differences in plasma parameters (IgA and IgG, serum amyloid) and no interaction between injection treatment and environment condition were found. GOS-enriched gene sets related to energetic metabolism in jejunum, and to lipid metabolism in cecum, were involved in gut barrier maintenance. A homogeneous reaction to heat stress was determined along the gut, which showed downregulation of the genes related to energy and immunity, irrespective of in ovo treatment. GOS efficacy in counteracting heat stress was scarce after ten days of environmental treatment, but the in ovo supplementation modulates group of genes in jejunum and cecum of broiler chickens
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