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Microbial carcass contamination during pig slaughter – a narrative overview on recent data and documentation in routine slaughter
No full textAs production of food from animal origin is always associated with microbiological contamination, there is a possible risk for consumers to be exposed to pathogenic microorganisms. It is therefore crucial to control microbiological contamination at all process steps with appropriate measures to detect contamination as soon as possible. To evaluate the effectiveness of reduction measures integrated into the slaughtering process, a baseline of contamination needs to be defined. Therefore, this review aimed to address sampling techniques and units used to describe levels of contamination on pig carcasses in routine slaughter by means of a narrative survey. Although Salmonella, Yersinia and Campylobacter are amongst the most relevant foodborne pathogens in pork production, we focussed on indicators of process hygiene such as Total Viable Count, Enterobacteriaceae , Coliforms and Escherichia coli . To compare the selected studies and trials, stratification by sampled matrix, sampling method, process step and unit was necessary. This investigation showed a wide variety of sampling techniques within those factors, which hinders the comparability of results across different studies. Furthermore, the reporting of standard statistical metrics was often inadequate, emphasising the need to harmonise sampling techniques and methodological reporting for both scientific and practical perspectives. Therefore, this review assessed the sampling methods used at each process step and for each sampled matrix individually and identified the missing statistical metrics. Establishing this foundation is essential for selecting the most relevant matrices and methods and for developing a guide to improve data quality and comparability across future studies
Development of a supportive mHealth device for persons with schizophrenia spectrum disorders (KisoLightApp): a usability study within a participant-involvement principle
No full textBackground
To address the severe treatment gap in persons with schizophrenia spectrum disorders (SSD), this study aims to examine the usability of and satisfaction with a novel and initial mHealth application (KisoLightApp) for SSD in Germany. The app is designed as a stand-alone tool that offers specific features such as symptom monitoring, medication adherence, and activity planning.
Method
Within a single-arm usability trial, N = 19 participants engaged with the app over 2 weeks and completed baseline and post-engagement assessments. Quantitative and qualitative measures were included to assess feedback for the continuous development of the KisoApp.
Results
The majority of participants engaged with the app regularly (n = 17 [89.50%], multiple times per week or daily). Descriptive results indicate a high usability and satisfaction with the app. Although a few unserious unwanted events (UEs) were reported, there were no serious UEs or adverse treatment reactions (ATR), indicating the safety of the app.
Conclusion
The KisoLightApp for persons with SSD seem to be a safe, usable, and satisfying tool for supporting the addressed population. Future studies should examine an enhanced version of the app within a randomized controlled trial, including a larger sample size and additional therapeutic features
Environmental and cultural transformations in the Lake Baikal Region reflect hemispheric-scale changes in temperature and atmospheric circulation over the past 8800 years
No full textCharacterised by heterogeneous microclimatic conditions, a sharp vegetation gradient and a rich archaeological record, Olkhon Island offers a unique setting to investigate past climate change and its potential influence on cultural trajectories in the Lake Baikal Region (LBR). Palynological and geochemical analyses of the uppermost 556 cm section of the 750 cm long, radiocarbon-dated sediment core (Nur-II) from Lake Nurskoye (53°3'N, 106°58'E; 456 m a.s.l.) at the western end of Olkhon Island reveal several long- and short-term climate shifts over the last 8800 years. Forest expansion beginning in the Early Holocene peaked during the second half of the 7th millennium cal BP, followed by a continuous decline culminating around 1500 cal yr BP, when open steppe vegetation reached its maximum extent. This pattern supports the long-debated hypothesis that landscape openness and the associated availability of herbivorous game were key drivers of population size, social practices and subsistence strategies among Mesolithic, Neolithic and Bronze Age hunter-gatherer communities in the region. The maximum expansion of steppe vegetation (ca. 3400–800 cal yr BP) likely attracted Bronze Age pastoral groups who migrated into the area around 3300 cal yr BP, as corroborated by the Nur-II palynological record and archaeozoological data from the LBR. However, the pollen data show no evidence that the mixed foraging-pastoral subsistence was supplemented by crop cultivation prior to the Middle Ages (i.e. 1360 cal yr BP). The pollen-inferred moisture trends on millennial to centennial scales, including the 8.2 and 4.2 ka BP cooling events, show a positive correlation with the intensity of the Asian summer monsoon circulation throughout the study period. This suggests that the region’s hydrology was primarily controlled by a south-easterly circulation regime during the Early–Middle Holocene, while westerly-derived moisture became increasingly important after ca. 7000 cal yr BP
Mucin-Inspired Filamentous Sulfated Copolymers Effectively Inhibit Human Respiratory Syncytial Virus (hRSV) Infectivity
No full textVirucidal compounds capable of binding to and disrupting viruses represent a promising avenue for antiviral applications. In this study, the development of high molecular weight (≈300 kDa) dendronized polyglycerol-based mucin-inspired amphiphilic statistical copolymers (MIACPs) is reported using the RAFT polymerization technique. These copolymers comprise ≈30% repeat units containing aliphatic C11 carbon chains with terminal carboxylate (MIACP-1) and alkyl (MIACP-2) functionalities, while the remaining ≈70% of the repeat units consist of dendronized polyglycerol sulfates. Structural characterization using cryo-electron microscopy (cryo-EM) and small-angle neutron scattering (SANS) reveals that MIACPs form single-chain filamentous structures, similar to natural porcine gastric mucin (PGM). These biocompatible MIACPs exhibit strong, sulfate-dependent inhibition of human respiratory syncytial virus (hRSV), with exceptionally low IC50 values (C = ≈0.25 µg mL−1). The virucidal activity is assessed using serial dilution experiments, which confirms that MIACPs demonstrate virucidal activity, indicating a very strong binding affinity of the polymers to the hRSV. In contrast, a similar molecular weight homopolymer composed solely of sulfated dendronized repeat units exhibits comparable hRSV inhibition activity but lacks any virucidal effect. Therefore, designing a statistical copolymer with ≈30% virucidal functionality is unique in that it renders the copolymer virucidal without compromising its inhibitory activity
Narcophin und seine Anwendung bei Hunden
No full textDigitalisat der Ausgabe von 1920, erschienen 202
Towards theoretical synergies in mathematics teacher noticing
No full textTeacher noticing represents a fundamental dimension of mathematics teaching expertise, yet the research in this area remains theoretically fragmented, limiting comprehensive understanding of this multifaceted professional capability. In this paper, we explore potential synergies between five different theoretical perspectives on mathematics teacher noticing identified in prior research: (a) a cognitive-psychological perspective, in which teacher noticing is conceptualised as a set of mental processes used when observing and interpreting classroom events; (b) an expertise-related perspective, which emphasises differences in the noticing capabilities of novice and expert teachers; (c) a discipline-specific perspective, which highlights the development of awareness of one’s noticing; (d) a socio-cultural perspective, in which noticing is treated as a socially situated activity shaped by discursive practices and socio-political contexts; and (e) an ecological-embodied perspective, in which noticing is understood as an embodied activity emerging through teachers’ engagement with their classroom environments. Through a narrative review and systematic comparison of these perspectives, we identify key distinctions in their conceptualisation of noticing, units of analysis, and approaches to learning to notice. We then use deliberate cross-perspective dialogue to generate insights that address theoretical blind spots and challenge traditional paradigmatic boundaries. We conclude by proposing future research directions emphasising inter-theoretical, multi-theoretical, and meta-theoretical inquiry to advance understanding of mathematics teacher noticing
SIMPLICITY is an agent-based, multi-scale mathematical model to study SARS-CoV-2 intra- and between-host evolution
No full textComputational tools are frequently used to describe pathogen evolutionary dynamics either within infected hosts or at the population level. However, there is a lack of models that capture the complex interplay between within-host and between-host evolutionary dynamics, leaving a knowledge gap with regard to realistic evolutionary dynamics. We present SIMPLICITY, a multi-scale mathematical model that combines within-host disease progression and viral evolution with a population-level model of virus transmission and immune evasion. We parameterize SIMPLICITY based on SARS-CoV-2 within-host viral dynamics, observed evolutionary rates, and dynamics of immune waning. We then apply it to study the dynamics and mechanisms driving SARS-CoV-2 evolution at the population level. We compare a baseline toy model of gradually increasing transmission fitness with an adaptive fitness landscape model that accounts for infection history and immune waning. Our simulations demonstrate that escape from population immunity generates evolutionary dynamics encompassing selective sweeps, which resemble SARS-CoV-2 evolution
Artificial intelligence predicts c-KIT exon 11 genotype by phenotype in canine cutaneous mast cell tumors: Can human observers learn it?
No full textCanine cutaneous mast cell tumors (ccMCTs) are frequent neoplasms with variable biological behaviors. Internal tandem duplication mutations in c-KIT exon 11 (c-KIT-11-ITD) are associated with poor prognosis but predict therapeutic response to tyrosine kinase inhibitors. In a previous work, deep learning algorithms managed to predict the presence of c-KIT-11-ITD on digitalized hematoxylin and eosin-stained histological slides (whole-slide images, WSIs) in up to 87% of cases, suggesting the existence of morphological features characterizing ccMCTs carrying c-KIT-11-ITD. This 3-stage blinded study aimed to identify morphological features indicative of c-KIT-11-ITD and to evaluate the ability of human observers to learn this task. 17 untrained pathologists first classified 8 WSIs and 200 image patches (highly relevant for algorithmic classification) of ccMCTs as either positive or negative for c-KIT-11-ITD. Second, they self-trained to recognize c-KIT-11-ITD by looking at the same WSIs and patches correctly sorted. Third, pathologists classified 15 new WSIs and 200 new patches according to c-KIT-11-ITD status. In addition, participants reported microscopic features they considered relevant for their decision. Without training, participants correctly classified the c-KIT-11-ITD status of 63%–88% of WSIs and 43%–55% of patches. With self-training, 25%–38% of WSIs and 55%–56% of patches were correctly classified. High cellular pleomorphism, anisokaryosis, and sparse cytoplasmic granulation were commonly suggested as features associated with c-KIT-11-ITD-positive ccMCTs, none of which showed reliable predictivity in a follow-up study. The results indicate that transfer of algorithmic skills to the human observer is difficult. A c-KIT-11-ITD-specific morphological feature remains to be extracted from the artificial intelligence model
Deactivation of ceramide de novo synthesis induces cerebral angiogenesis and microvascular remodeling post-ischemia/reperfusion in mice via mechanisms not predominated by extracellular vesicles
No full textCeramide is a major constituent of membrane microdomains and controls cell signaling. Previous studies showed that ceramide exacerbates cerebral ischemia/reperfusion injury and that inhibition of acid sphingomyelinase (ASM), which converts sphingomyelin to ceramide, promotes microvascular remodeling via induction of extracellular vesicles (EVs) release. ASM inhibitors have so far not translated into clinical stroke therapies. Of note, ceramide levels can also be lowered by inhibition of serine palmitoyltransferase (SPT), which is the rate-limiting enzyme of ceramide de novo synthesis. To evaluate this pathway as a potential therapeutic target for stroke, we exposed cerebral microvascular endothelial cells to the SPT inhibitor myriocin or induced SPT knockdown by siRNA. Deactivation of de novo ceramide synthesis increased endothelial tube formation, migration, VEGF secretion, and EV release. These EVs did not induce angiogenesis in tube formation assays. Using light sheet microscopy, we demonstrate that myriocin-mediated SPT inhibition increases the length and branch density of thin microvessels (<4 µm diameter), which are drivers of angiogenesis, in the previously ischemic brain tissue of mice exposed to middle cerebral artery occlusion. These data highlight the importance of ceramide de novo synthesis for post-ischemic microvascular remodeling and angiogenesis, while its mode of action differs from ASM inhibitors