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VeRidium: a fully immersive and interactive virtual reality educational environment
No full textWe present VeRidium, a fully immersive and interactive virtual reality environment for the utilization in university-level teaching. In a comparative study, one cohort of students was revisiting the fundamental structures of the metals in the virtual environment, another cohort was given the same tasks with clay models. Pre-Post-Test analyses reveal the efficacy and strengths of the virtual environment despite a larger preparational effort. Some lessons-learned are given from our journey starting with the programming of the environment from scratch, to final upload in the app store and implementation in lecture halls
Towards a new paradigm for memory politics on colonial past in Africa: an analysis of the couple franco-allemand?
No full textRisk management practices and financial performance: an empirical analysis of the international real estate industry
No full textCorticomuscular coherence during upright standing in unilateral transfemoral amputees
No full textPatients with a lower limb amputation suffer from an impaired balance control and thereby are at a higher risk to fall. To cope with this deficit, they adapt their neuromuscular system by modifying biomechanical and neuromuscular structures. In this study, we investigated changes in corticomuscular coherence between the motor cortex and muscles of the trunk and the intact lower leg. We recorded electroencephalogram (EEG) and electromyogram (EMG) data from 10 unilateral transfemoral amputees and 10 age-matched able-bodied controls during quiet upright stance with eyes open, eyes closed and during dual tasking. To analyse afferent and efferent corticomuscular coherence, directional wavelet coherence between EEG and EMG signals was computed. The corticomuscular coherence analysis showed significant differences between amputees and controls in the afferent and efferent direction and across visual conditions, suggesting differences in the processing of sensory feedback. A power spectral density analysis of the motor cortex contralateral to the amputated leg of amputees showed increased power, as well as a pronounced decrease in alpha frequencies indicating an increased cognitive load. This exploratory study stimulates further hypotheses on how coordination of brain and muscle activity is modulated after a lower limb amputation
Heterogeneity in response to GLP-1 receptor agonists in type 2 diabetes in real-world clinical practice: insights from the DPV register - an IMI-SOPHIA study
No full textAims/hypothesisGlucagon-like peptide-1 receptor agonists (GLP-1 RAs) are a cornerstone in type 2 diabetes management. In this study we evaluated heterogeneity in body weight and glycaemic responses to the initiation of liraglutide, semaglutide or dulaglutide in real-world clinical practice.MethodsData from 4467 adults with type 2 diabetes in the Diabetes Patient Follow-up (DPV) registry were analysed, focusing on changes in HbA1c and body weight over 6 months following initiation of a GLP-1 RA. We categorised participants based on their response: HbA1c reduction only, weight loss only, both or neither. This analysis was part of the IMI-Stratification of Obesity Phenotypes to Optimize Future Obesity Therapy (IMI-SOPHIA) project.ResultsAt 6 months’ follow-up the median absolute HbA1c reduction was 5.3 mmol/mol (IQR 13.9, −1.0) (0.49% [1.27, −0.09]) and relative body weight reduction was 1.43% (4.26, 0). Only 14% of participants achieved meaningful reductions in both HbA1c (absolute reduction ≥5.5 mmol/mol [0.5%]) and body weight (relative reduction ≥5%). Men and those with a higher baseline HbA1c were more likely to show an HbA1c only response (36% of participants; both pConclusions/interpretationThere is significant heterogeneity in responses to GLP-1 RA therapy among individuals with type 2 diabetes in routine clinical practice. However, in our study a substantial proportion achieved a reduction in either body weight or HbA1c. Future studies should explore why some individuals achieve either weight loss or HbA1c reduction but not both
Influence of pretreatment strategies on the tensile bond strength of 3D printed composite resins for definitive cementation to dentin
No full textStatement of problemLittle is known about factors influencing the bond strength of additively manufactured materials in dentistry. The impact of diverse pretreatment strategies on the bond strength of 3-dimensionally (3D) printed composite resins indicated for definitive cementation to dentin has scarcely been investigated.PurposeThe aim of this study was to evaluate the adhesive bond strength of two 3D printed definitive fixed restoration materials to dentin by using different pretreatment protocols.Material and methodsComposite resin rods (2×2×10 mm, n=20/group) were 3D printed with 3Delta Crown and saremco print CROWNTEC. Half of the rods were airborne-particle abraded (APA), the other half of the rods were untreated. All rods were chemically conditioned with 1 of 3 adhesives (Adhese Universal, Heliobond, Monobond Plus). Dentin rods (2×2×5 mm) were cut from bovine teeth, pretreated with Adhese Universal, and bonded to the composite resin rods with Variolink Esthetic LC. The specimens were thermocycled (10 000 cycles) before testing for tensile bond strength (TBS) and the assessment of the failure mode. Surface roughness (SR) and degree of conversion (DC) were examined with laser scanning microscopy and Raman spectroscopy. Data were statistically analyzed with 1-, 2-, and 3-way analyses of variance (ANOVAs) and Weibull analysis (α=.05).ResultsTBS values ranged from 6.57 to 10.58 MPa, without significant differences among the groups (P>.05). All groups demonstrated a comparable Weibull modulus and predominant adhesive failure. SR increased significantly (PConclusionsRegardless of the 3D printable material, SR was increased by APA, and the DC was around 70%. Different mechanical and chemical pretreatments appear to exert relatively little influence on TBS
Tacrolimus mitigates pathological patterns in mouse models of Alzheimer’s disease
No full textNeuroinflammation and disruptions in glutamatergic neurotransmission are hallmark features of Alzheimer’s disease (AD). Various compounds have been investigated for their potential to modulate these processes in this disease. Tacrolimus (FK506), a calcineurin inhibitor (CNI), has been suggested as a candidate for the treatment of AD, although its effects and possible mechanisms have not been extensively evaluated. Here we investigated whether tacrolimus treatment could mitigate cognitive deficits, neurotoxicity, and microgliosis in AD models, including Aβ1–42-induced intrahippocampal damage and middle-aged transgenic APP/PS1 mice, as well as improve glutamate release dysregulation in synaptosomes from the latter. A single dose of tacrolimus prevented the cognitive impairment induced by intrahippocampal microinjection of Aβ1–42 in the novel object recognition test (NORT), and reduced the neurodegeneration. Interestingly, in the APP/PS1 model, a 30-day treatment with the drug did not prevent memory impairment in the NORT, albeit it improved the social interaction and partially reduced microgliosis. Finally, tacrolimus restored the intrasynaptotosomal calcium levels and normalized impaired glutamate release in synaptosomes from APP/PS1 mice. These findings provide new evidence that both acute and chronic treatment with tacrolimus exerts neuroprotective effects, providing a foundation for the potential therapeutic application of this CNI in managing AD
Site, season and soil depth affect the composition of root exudates in three temperate tree species
No full textRoot exudation is a key process for plants to acquire nutrients. This process works directly, or indirectly through the microbiome priming effect. Likewise, plants release a significant amount of carbon into the soil, which stresses the importance of root exudation for carbon cycling. Nonetheless, detailed data on root exudation, especially compound-specific data from forest trees are scarce, but urgently needed. Recent studies suggest a high importance of the forest floor for nutrient acquisition, which is therefore of special interest for studying root exudates.In this study, we sampled root exudates of Fagus sylvatica, Picea abies and Acer pseudoplatanus at four temperate forest sites with varying mean annual air temperature, annual precipitation sums and soil phosphorus (P) levels. Samplings took place in spring and autumn and in two soil depths: the forest floor (surface layer of the forest soil with ≥ 15% organic carbon) and the upper mineral soil (A5 horizon). Root exudates were collected using an in-situ cuvette-based approach. For this purpose, living tree roots were cleaned, and after a period of recovery, incubated for 24 hours in a cuvette filled with glass beads and a nutrient solution. Compounds in the retrieved solution were analysed by a mass spectrometer coupled to a gas chromatograph.81 compounds were included in the analysis and divided into functional groups. All studied species showed higher exudation in spring compared to autumn with a higher share of amines in spring. Differences in exudation patterns between species could be detected for the two soil depths: While F. sylvatica showed a higher exudation in the forest floor, P. abies and A. pseudoplatanus exuded more in the mineral soil. This pattern is expected for F. sylvatica and A. pseudoplatanus, since F. sylvatica, which usually is associated with ectomycorrhiza (ECM), is said to follow an organic nutrient strategy and A. pseudoplatanus, which usually is associated with arbuscular mycorrhiza (AM), is said to follow an inorganic nutrient strategy. However, the behaviour of P. abies usually being associated with ECM and therefore following an organic nutrient strategy is in contrast to what literature suggests. A site-species-interaction effect was found with increased exudation on P-poor sites with low temperature for F. sylvatica, and with high temperature for P. abies and A. pseudoplatanus.Facing a thinning of the forest floor with globally increasing temperatures, studying root exudation can indicate the forest floor’s role for tree nutrition. Clear differences in root exudation in quantity and composition between species, seasons and soil depths urge the need for further research to elucidate the effect of site conditions on exudation patterns
A screening approach unveils an unknown Mn2+-dependent endopolyphosphatase activity in yeast
No full textInorganic polyphosphate (polyP) is a ubiquitous biopolymer composed of multiple orthophosphates connected by energy-rich phosphoanhydride bonds. In organisms, polyP is digested by two types of enzymes: exopolyphosphatases, which shorten the chain from the ends by cleaving off monophosphate units, and endopolyphosphatases, which cut the chain internally. While several continuous methods are available to monitor exopolyphosphatase activity, endopolyphosphatase activity assays are less common and typically involve multiple tedious steps. Here, we introduce FRET-polyP8 , a novel probe for real-time detection of endopolyphosphatase activity. The FRET assay enabled rapid, highly sensitive, single-step detection of specific endopolyphosphatase activity both from isolated proteins and cell extracts. The simple read-out additionally enabled enzyme inhibitor screening. Furthermore, a novel Mn2+ -dependent endopolyphosphatase activity in baker's yeast was detected in a quadruple mutant, highlighting the ability to screen for metal-dependence of new endopolyphosphatase activity. This approach thus represents a significant addition to existing methodologies, facilitating the discovery and classification of new endopolyphosphatases and their inhibitors to advance our understanding of polyP metabolism and regulatio