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Post-glacial vegetation trajectories on the Eastern Tibetan Plateau reflect millennial-scale migration lags in complex mountain terrain based on sedimentary ancient DNA and dynamic dispersal modeling
Get PDFMountains with complex terrain and steep environmental gradients are biodiversity hotspots such as the eastern Tibetan Plateau (TP). However, it is generally assumed that mountain terrain plays a secondary role in plant species assembly on a millennial time-scale compared to climate change. Here, we investigate plant richness and community changes during the last 18,000 years at two sites: Lake Naleng and Lake Ximen on the eastern TP with similar elevation and climatic conditions but contrasting terrain. We applied plant DNA metabarcoding to lake sediments leveraging a new regional reference database for taxa identification. Furthermore, we developed a simplified species dispersal model named SMARC. This was used to simulate species migration along river valleys in response to past climate change at the taxonomic resolution of the sedimentary ancient DNA (sedaDNA) approach. Statistical analyses, including ordination-based ecological trajectory analysis, yielded a significant match between sedaDNA and simulated results at single taxon and community levels including certain site-specific differences. Steep terrain downstream of Lake Naleng enhances connectivity to glacial lowland refugia during postglacial warming. In contrast, gentle terrain over long distances implies weak connectivity to the lowland and thus resulted in a strong migration lag at Lake Ximen. Likewise, terrain differences among our sites defined the different connectivity to alpine refugia during late-Holocene cooling. Our consistent proxy- and model-based results, for the first time, indicate that dispersal related migration lags in complex mountain terrain lead to uneven vegetation trajectories at sites with similar climatic conditions mainly because of differences in connectivity to refugia. Ultimately our results indicate that connectivity to refugia is a first-order factor for species migration in addition to elevation-related climatic conditions shaping the postglacial vegetation trajectory in mountainous terrain. This has hitherto largely been ignored when forecasting mountain vegetation responses to climate change and related risk assessment
Half a century of temperate non-forest vegetation changes : no net loss in species richness, but considerable shifts in taxonomic and functional composition
Get PDFIn recent decades, global change and local anthropogenic pressures have severely affected natural ecosystems and their biodiversity. Although disentangling the effects of these factors is difficult, they are reflected in changes in the functional composition of plant communities. We present a comprehensive, large-scale analysis of long-term changes in plant communities of various non-forest habitat types in the Czech Republic based on 1154 vegetation-plot time series from 53 resurvey studies comprising 3909 vegetation-plot records. We focused not only on taxonomic diversity but also on the functional characteristics of communities. Species richness of most habitat types increased over time, and taxonomic and functional community composition shifted significantly. Habitat specialists and threatened species became less represented in plant communities, indicating a decline in habitat quality. The spread of trees, shrubs, tall herbaceous plants, strong competitors, and nutrient-demanding species in all non-forest habitats, coupled with the decline of light-demanding species, suggests an effect of eutrophication and natural succession following the abandonment of traditional management. Moreover, we identified specific trends in certain habitats. In wetlands, springs, and mires, moisture-demanding species decreased, probably due to drainage, river regulations, and increasing drought resulting from climate change. Dry grasslands, ruderal, weed, sand, and shallow-soil vegetation became more mesic, and successional processes were most pronounced in these communities, suggesting a stronger effect of abandonment of traditional management and eutrophication. In alpine and subalpine vegetation, meadows and mesic pastures, and heathlands, insect-pollinated species declined, and the proportion of grasses increased. Overall, these functional changes provide deep insights into the underlying drivers and help conservationists take appropriate countermeasures
On the impact of aromatic core fluorination in hydrogen-bonded liquid crystals
No full textHerein we report the impact of fluorine substitution on the liquid crystalline (LC) self-assembly of supramolecular hydrogen-bonded rod-like architectures. This was systematically investigated by introducing fluorine atom at different positions or with different numbers on the investigated supramolecules. Therefore, eight different groups of hydrogen-bonded LCs (HBLCs) were designed and synthesized in which four 4-hexyloxybenzoic acid derivatives without or with fluorine substitution were used as proton donors. The proton acceptors are fluorinated or nonfluorinated alkyloxyazopyridine derivatives. The hydrogen bond formation between the complementary components was proved using FTIR and 1H NMR spectroscopy. All HBLCs were investigated for their mesomorphic behaviour using various tools such as differential scanning calorimetry (DSC), polarized optical microscopy (POM) and X-ray diffraction (XRD). Depending on the position and number of fluorine atoms different LC phases were observed including nematic, orthogonal non-tilted smectic A (SmA) or tilted smectic C (SmC) phases in addition to an unknown X phase. Depending on the position of the fluorine substitution, it was proved from the XRD investigations that different types of cybotactic nematic phases (NCyb) are exhibited by the reported HBLCs. Because of cis–trans photoisomerization under light irradiation of the reported HBLCs, their photo responsivity was investigated in solutions as well as between the different LC phases. This report provides key insights into the structure–property relationships of HBLCs, which might be of interest for optical storage device applications
Droits des LGBT et liberté de conscience en Tunisie : entre normes Islamiques et droits individuels
Get PDFMots-clés: Tunisie, constitution, législation, religion, sécularismeKeywords: Tunesien, Verfassung, Gesetzgebung, Religion, SäkularismusKeywords: Tunisia, constitution, legislation, religion, secularis
Comments and illustrations of the European Federation of Societies for Ultrasound in medicine guidelines : benign pleura lesions (benign pleura thickening, lesions and masses) : what can be seen on transthoracic ultrasound?
Get PDFPleural thickening can be the result of inflammation or infection but can also have a neoplastic origin. Depending on the clinical context, a pleural lesion or mass is often initially suspected of malignancy. Benign pleural tumors are rare, and their appearance on ultrasound (US) is also described less frequently than pleural metastases or malignancies. There are few descriptions of contrast-enhanced Ultrasound (CEUS) in particular. This review introduces the basics of transthoracic ultrasound (TUS) of the pleura and CEUS of the pleura and lung. CEUS is recommended for pulmonary applications in the EFSUMB guidelines in non-hepatic applications. This article provides an overview of the characteristics of benign pleural thickening, tumor-like lesions, and benign pleural tumors on transthoracic B-mode US with color Doppler imaging (CDI) and CEUS. In detail, characteristics in TUS and CEUS are described for infectious/inflammatory pleural thickening (empyema, tuberculous pleuritis, hemothorax, fibrothorax), pleural thickening in various systemic diseases, in tumor-like conditions (plaques, splenosis, endometriosis, mesothelial cysts, lymphangiomatosis) and benign tumors (lipoma, benign SFT, schwannoma, solitary extramedullary/extraosseous plasmacytoma). The descriptions are illustrated by corresponding US and CEUS images
Inflammation and limited adaptive immunity predict worse outcomes on immunotherapy in head and neck cancer
No full textMost patients with relapsed or metastatic head and neck squamous cell carcinoma (rmHNSCC) do not experience durable responses to PD-1 immune checkpoint inhibitors. PD-L1 tissue expression is the most commonly assessed response marker, but an insufficient predictor of treatment outcome. To identify suitable response biomarkers, we profiled the FOCUS trial (Registered at ClinicalTrials.gov: NCT05075122) cohort for several blood- and tissue-based markers. PD-L1 levels in the tumor or tumor microenvironment were not associated with treatment benefit. In contrast, inflammation-related markers such as IL-6, sCD25, and sTIM-3, as well as high peripheral neutrophils, cell-free DNA levels, and T cell receptor repertoire clonality, were associated with poor clinical outcomes. Patients lacking these high-risk markers performed remarkably well on inhibition of immune checkpoints with pembrolizumab. Biomarker-guided patient selection for pembrolizumab monotherapy or novel combinatorial approaches—potentially including anti-inflammatory agents—for patients with immune-impaired, inflammatory profiles may be the next step in personalizing immunotherapy for these hard-to-treat patients
Alzheimer's disease and its co-pathologies : implications for hippocampal degeneration, cognitive decline, and the role of APOE ε4
No full textINTRODUCTION: In neurodegenerative dementias, the co-occurrence and interaction
of amyloid β peptide (Aβ), tau pathology, and other pathological lesions confound
their individual contributions to neurodegeneration and their modulation by risk
factors. METHODS: We analyzed 480 post mortem human brains (ages 50–99) using regression
and structural equation models to assess the relationships among Aβ, tau,
limbic-predominant age-related TDP-43 encephalopathy neuropathological changes
(LATE-NC), α-synuclein, other age-related lesions, and apolipoprotein E (APOE) ε4, as
well as their effects on CA1 neuronal density, brain weight, and cognitive status.
RESULTS: Aβ, tau, LATE-NC, and amygdala-predominant α-synuclein pathology were
mutually interdependent. Tau was the strongest predictor of global neurodegeneration,
while LATE-NC primarily, but not exclusively, affected hippocampal neuron loss.
Small vessel disease correlatedwith both LATE-NC and α-synuclein,while APOE ε4 was
mainly associated with extracellular parenchymal and capillary Aβ pathology.
DISCUSSION: Although Alzheimer’s disease pathology plays a central role in brain
degeneration, coexisting pathologies can both exacerbate and independently contribute
to it. These factors should be considered in patient stratification
MLUH-E-115_1, Falco naumanni Fleischer, JG, 1818, eggshell
No full textInventory No.: MLUH-E-115_1, Object: eggshell, Species: Falco naumanni Fleischer, JG, 1818, Preservation: complete preservation, Locality_loc.: Parnass, Locality today: Parnassus, Country: GreeceCollector_leg.: Dr. T. J. Krüper, Date: ?, Collection_coll.: M. Schönwetter, published in Handbuch der Oologie, Schönwetter, Max: Vol. I, p. 192, Identification by: M. Schönwetter, Aquisition: 1927, Aquired from: Dr. Henrici, ex Collection: ex. Coll. Dr. Henrici; ex. Coll. Dr. T. J. Krüpe
MLUH-E-89_3, Falco tinnunculus Linnaeus, 1758, eggshell
No full textInventory No.: MLUH-E-89_3, Object: eggshell, Species: Falco tinnunculus Linnaeus, 1758, Preservation: complete preservationCollection_coll.: M. Schönwetter, published in Handbuch der Oologie, Schönwetter, Max: Vol. I, p. 192, Identification by: J. Dahlk
Impacts of fertilization on metal(loid) transfer from soil to wheat in a long-term fertilization experiment - using 87Sr/86Sr isotopes as metal(loid) tracer
No full textFertilizers are widely used to sustain food production but can alter soil chemistry and potentially contribute toxic metal(loid)s to agricultural systems. For the first time, this study examined the occurrence of select metal(loid)s (Zn, Sr, V, As, Cd, Pb, and U) alongside the 87Sr/86Sr isotope ratio in agricultural soil– both total and mobile pools– and wheat grain. Samples were collected from one of four fertilization treatments– mineral (NPK), organic (manure), combined mineral+organic, and unfertilized controls– within the 120-year Static Fertilization Experiment in Bad Lauchstädt, Germany. Fertilization treatments altered soil pH and organic carbon resulting in mineral fertilization lowering pH and increasing cation mobility (Cd, Zn, Sr), whereas organic fertilization increased pH and enhanced the mobility of non-cationic elements (V, As). These effects translated into higher Cd in mineral-fertilized wheat grain and higher As in mineral+organic wheat grain. Fertilization shifted the 87Sr/86Sr ratios in soils and wheat grains toward that of the applied fertilizers, with mineral and mineral+organic wheat grains inheriting the triple super phosphate signature (0.70778) and organic wheat grains matching manure (0.70883). The 87Sr/86Sr ratio in the mobile soil pool was correlated with mobile As, V, and P, demonstrating that the 87Sr/86Sr ratio reflects both fertilizer source and the mobility of select co-occurring metal(loid)s. Overall, this study demonstrates metal(loid) enrichment in soil and wheat from fertilization and establishes 87Sr/86Sr ratio as a robust tracer of fertilizer impacts. These findings underscore the need for targeted fertilization strategies to reduce contaminant accumulation in agroecosystems