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Fast 3D UTE in vivo T1 and T∗2 mapping of fast relaxing knee tissues at 3 T
No full textPurpose
UTE MR imaging captures quantitative signals in fast-relaxing tissues, enabling anatomical visualization and quantitative assessment of T1 and
relaxation times. However, the clinical application of quantitative UTE MRI is limited by long acquisition times. Therefore, this study introduces a novel UTE-based method for T1 and
mapping, achieving submillimeter resolution in less than 10 min.
Theory and Methods
The method employs a dual-echo acquisition for fast
mapping, augmented by an additional acquisition with different T1 weighting. This second scan enables the computation of signal ratios between scans with different T1-weighting. These measured signal ratios are then compared to a lookup table containing distinct ratios, corresponding to discrete T1 values. The approach was validated in phantom solutions mimicking various T1 and
times and applied in vivo to quantify relaxation times across different knee tissue compartments in healthy individuals.
Results
The method demonstrated its reliability for T1 and
quantification in rapidly relaxing tissues (1–11 ms). However, it exhibited a tendency to underestimate
in skeletal muscle. This limitation arises from the chosen TEs being inadequate to capture slow signal decays. In accordance with the findings of preceding studies, this in vivo study identified three distinct T1 categories of tissue characterized by short (adipose tissue), moderate (ligaments, tendons, and menisci), and long (skeletal muscle) T1 values.
Conclusion
The presented technique for combined T1 and
mapping enables relaxometry in rapidly relaxing tissues, indicating potential for advanced tissue characterization in clinical settings
Comprehensive life cycle assessment of selected seasonal thermal energy storage systems
No full textThe utilization of seasonal thermal energy storage (sTES) systems is essential for balancing fluctuations between demand and surplus of heating/cooling in modern energy systems and to reduce overall greenhouse gas emissions from space heating. However, large storage volumes are required to store the heat over extended periods leading to a high demand for construction materials and processes. Yet, no comprehensive environmental evaluation compares sTES technologies across their life cycle phases. This study employs life cycle assessment to quantify the environmental impacts of three different type of sTES: a tank thermal energy storage (TTES), a water-gravel thermal energy storage (WGTES), and a pit thermal energy storage (PTES). Aquifer thermal energy storage (ATES) systems are also included as reference for evaluating the results. Greenhouse gas emissions from the construction phase vary between 1.4 (PTES) and 29.4 g CO2-eq/kWhth (WGTES), depending on the type of installation, storage size, and construction materials. Utilizing water as a filling material and large storage volumes with reduced surface-to-volume ratios enhance environmental performance. Controversely, materials such as concrete, steel, foam glass gravel, and related transport processes contribute significantly to the environmental impact. These should be replaced wherever possible by sustainable alternatives without compromising storage capacity and efficiency
Wheat variety mixtures enhance yield stability and result in pronounced overyielding for certain line combinations
No full textMonocultures dominate crop production but face challenges such as vulnerability to pests, diseases, and environmental changes. To address this, growing mixtures of lines has gained attention for its potential to improve crop resilience. Our study investigated the overyielding effects of wheat mixtures compared to their individual lines under different management scenarios. Field trials conducted over two growing seasons at three locations in Germany included 46 inbred lines, 12 hybrids, and 94 mixtures tested under low- and high-input conditions. Results showed that wheat mixtures demonstrated both mid-component and better-component overyielding, with stronger effects under low-input conditions. Mid-component performance and general mixing ability were effective in predicting mixture performance, while trait differences of the pure lines and the heterogeneity index had little impact on overyielding effects. Instead, a negative correlation was found between better-component overyielding and yield differences. Mixtures exhibited significantly greater yield stability than pure stands across scenarios. Genotype-based stability indices further supported the enhanced stability of mixtures. These findings demonstrate the benefits of wheat variety mixtures in improving performance and stability, offering guidance for their effective use and highlighting the need for further research to improve mixture performance
Population-wide single-pollen nuclei genotyping in rye sheds light on the genetic basis and environmental plasticity of meiotic recombination
No full textThe core molecular machinery of meiosis is conserved deep across eukaryotic lineages. Nevertheless, recombination landscapes vary at multiple scales, from chromosomes to populations, caused by an interaction between genetic and environmental factors. To improve our understanding of the causes and consequences of this variation, we need to identify the underlying genetic architecture.
In this work, we explored the genetic basis and environmental plasticity of meiotic recombination in a large rye population grown under control and nutrient-deficient conditions. We used single-pollen nuclei (SPN) genotyping to directly measure male meiotic crossovers in 3136 pollen nuclei from 584 individuals.
We detected a significant reduction of crossovers in response to nutrient deficiency. Using genome-wide association scans, we uncovered the genetic basis of crossover count, crossover interference, and intrachromosomal shuffling. The presence of multiple additive loci with small to intermediate explained phenotypic variance suggested a polygenic architecture of crossover traits.
Loci associated with crossover traits were unique to control or nutrient-deficient conditions, suggesting that alleles regulating crossover traits are dependent on genotype-by-environment interactions, which strongly emphasizes the environmental plasticity of meiotic recombination. Finally, we revealed differences in recombination landscapes measured in gametophytes and sporophytes, which may be explained by a postmeiotic survivorship bias
Crop diversity in the landscape boosts pollinators and yield of pollinator dependent crops across the world
No full textThere is a global concern about the decline of wild pollinators and the ecosystem services they provide. Although land-use change is a major threat to biodiversity, it is still poorly understood how land-use heterogeneity (or land-use structure) impacts pollinator communities and entomophilous crop production. Based on a literature review, we performed a meta-analysis to (1) assess how landscape structure, both composition and configuration, affects pollinator species richness and abundance, and (2) examine the impact of landscape structure on the production of key entomophilous crops. We extracted information on pollinator communities and crop production from 101 studies with a total of 920 site replicates distributed widely across the globe. To obtain landscape structure (total area of all crops, crop diversity, and landscape Shannon’s Diversity Index) information, we sourced data from the database Map-SPAM as well as satellite images. We found that pollinator species richness increased with the number of crop species in the surrounding area. Pollinator abundance increased with the number of different crops but decreased with increasing agricultural area in the surrounding landscape. Crop production of several crops was associated with landscape heterogeneity. Notably, fruit set increased with an increasing number of crop species in neighbouring fields and decreased with increasing agricultural area, that is, when nature is substituted with agriculture in the surrounding landscape. We also found positive correlations between edge density of an area and pollinator species richness and entomophilous crop production suggesting that edge density can be used as a landscape structure indicator to assess pollinator diversity. The effects of landscape structure were more pronounced in crops with high pollinator dependence, showing stronger relationships with both pollinator diversity and crop production. These findings highlight the importance of maintaining landscape heterogeneity through crop diversity and natural habitats to support pollinators and their services, though unmeasured factors such as intensification or local management may also play a role
Cropping history, agronomic rules, and commodity prices shape crop rotations across Central Europe
No full textContext
Crop rotations provide agronomic benefits over monocropping, such as enhanced nitrogen supply, improved weed and pest control, and higher yields. Although the theoretical understanding of optimal rotations has advanced, little is known about their real-world implementation and the factors influencing rotation decisions on large scales.
Objective
Understanding these factors is key for projecting future cropping patterns, refining agricultural policy, and improving crop models that often oversimplify rotation practices. This study identifies the drivers influencing operational crop rotations across Central Europe and projects future cropping patterns in the region.
Methods
We analyse over 16 million field-year combinations from Germany, Austria, and the Czech Republic. Using a random forest algorithm, we determine feature importance and apply a novel machine learning approach that incorporates uncertainty in farmers' decision-making to provide a potential outlook on cropping patterns until 2070.
Results and Conclusions
Historical cropping patterns, agronomic practices, and legume commodity prices significantly shaped crop rotations across the region. Projections indicate a substantial increase in legume cultivation over the coming decades, with implications for nitrogen budgets, dietary transitions, and in-silico upscaling.
Significance
Rather than optimizing rotations, this study identifies key drivers of operational crop rotations in Central Europe. The findings provide the basis for large-scale simulations that represent cropping patterns more realistically. To the best of our knowledge, the data set compiled here is the most extensive yet analysed in the context of operational crop rotation management
Acetylplatinum(II) complexes containing PTA-derived ligands : synthesis, quantum-chemical characterization, and in vitro cytotoxicity
No full textAcetylplatinum(II) complexes containing the water-soluble phosphine ligands based on PTA (1,3,5-triaza-7-phosphaadamantane) were synthesized and structurally characterized: cis-[Pt(COMe)₂(PTA)₂] (3) and trans-[Pt(COMe)Cl(PTA)₂] (4). The trans-[Pt(COMe)₂(PTA)₂] (3a) was obtained from the methanol solution of 3 and structurally characterized. The compounds were investigated by elemental analysis, IR, multinuclear NMR spectroscopy, and mass spectrometry. X-ray crystallography confirmed the square-planar geometry of complexes 3 and 3a, and their supramolecular architectures were examined using Hirshfeld surface analysis. DFT calculations at the B3LYP/LanL2DZ level provided good agreement with experimental bond lengths and angles. NMR spectra were further supported by GIAO-calculated chemical shifts. Intermolecular and intramolecular interactions were elucidated through QTAIM analysis, revealing partial covalent character of metal-ligand bonds and weak non-covalent stabilizing interactions. Complexes 3 and 4 were tested for their in vitro cytotoxicity against five human cancer cell lines (8505C thyroid cancer, A253 head and neck tumor, A549 lung carcinoma, A2780 ovarian cancer, and DLD-1 colon carcinoma). Complex 3 showed selective activity against lung A549 and ovarian A2780 cell lines, comparable to cisplatin, whereas complex 4 exhibited broader but less selective cytotoxicity. These results suggest that the PTA-based acetylplatinum(II) complexes represent promising candidates for further development of water-soluble antitumor agents
MLUH-E-77_1 , Falco cherrug cherrug Gray, JE, 1834, eggshell
No full textInventory No.: MLUH-E-77_1 , Object: eggshell, Species: Falco cherrug cherrug Gray, JE, 1834, Preservation: complete preservation, Locality_loc.: Wolga; S. Russland, Locality today: Russia/Kazakhstan, Country: Russia/KazakhstanCollector_leg.: R. Tancré, Date: ?, Collection_coll.: M. Schönwetter, published in Handbuch der Oologie, Schönwetter, Max: Vol. I, p. 188, Identification by: M. Schönwetter, Aquisition: 1926, Aquired from: Dr. Henrici, ex Collection: ex.Coll. Dr. Henrici; ex Coll. R. Tancré, Additional Information: 4 eggs in one box Schoenwetter questioned all the eggs being from one clutch because of differences; in the eggs; I (Jessica Dahlke) agree with hi
MLUH-E-92_6, Falco tinnunculus Linnaeus, 1758, eggshell
No full textInventory No.: MLUH-E-92_6, Object: eggshell, Species: Falco tinnunculus Linnaeus, 1758, Preservation: complete preservation, Locality_loc.: Halberstadt, Locality today: Halberstadt, Country: GermanyCollector_leg.: R. Schmidt, Collection_coll.: M. Schönwetter, published in Handbuch der Oologie, Schönwetter, Max: Vol. I, p. 192, Identification by: M. Schönwetter, Aquisition: 1941, Aquired from: Dr. Henrici, ex Collection: ex. Coll. Dr. Henrici; ex. Coll. R. Schmid
Harmony, conflict, and evolution of the common agricultural policy in Europe : a text mining survey
No full textThe Common Agricultural Policy (CAP) represents one of the main initiatives of the European Union (EU) to develop and enhance agricultural sectors. This paper applies text mining and clustering to analyse changes in the CAP's main policy objectives based on 495 legislative texts adopted by the European Parliament. We develop an SSCIR-3F analysis framework that identifies five core CAP policy concerns—food security (S), sustainability (S), competitiveness (C), farmer income (I), and rural development (R), abbreviated as SSCIR—illustrates their internal conflicts using the conflict triangle, and explains their changing importance over time using agricultural development stage theory (food, farm, and future, 3F). The text mining results show that the importance of these five dimensions has gradually shifted. Sustainability has become the most prominent dimension in recent years, followed by farmer income, food security, and rural development. Clusters of documents further support this trend, with two clusters emphasising biodiversity, ecosystems, forests, and climate change. The changing trend of budget allocation also supports our results that the major concerns of CAP have been shifting over time. Overall, the evolving SSCIR priorities indicate that the CAP is moving towards a fairer, greener, and more flexible direction