High resolution ancient sedimentary DNA shows that alpine plant diversity is associated with human land use and climate change.

The European Alps are highly rich in species, but their future may be threatened by ongoing changes in human land use and climate. Here, we reconstructed vegetation, temperature, human impact and livestock over the past ~12,000 years from Lake Sulsseewli, based on sedimentary ancient plant and mammal DNA, pollen, spores, chironomids, and microcharcoal. We assembled a highly-complete local DNA reference library (PhyloAlps, 3923 plant taxa), and used this to obtain an exceptionally rich sedaDNA record of 366 plant taxa. Vegetation mainly responded to climate during the early Holocene, while human activity had an additional influence on vegetation from 6 ka onwards. Land-use shifted from episodic grazing during the Neolithic and Bronze Age to agropastoralism in the Middle Ages. Associated human deforestation allowed the coexistence of plant species typically found at different elevational belts, leading to levels of plant richness that characterise the current high diversity of this region. Our findings indicate a positive association between low intensity agropastoral activities and precipitation with the maintenance of the unique subalpine and alpine plant diversity of the European Alps.

Genetic Characterization of the Factor VIII Gene in a Cohort of Colombian Patients with Severe Hemophilia A with Inhibitors.

Hemophilia A is an X-linked bleeding disorder caused by mutations in the FVIII gene. Genetic factors have been shown to be a risk factor for the development of inhibitors. We aimed to identify the specific variations of the FVIII gene of patients with hemophilia A with inhibitors and their association with the inhibitor titer. Methods: Cross-sectional descriptive study. We included 12 Colombian patients from a health care provider, "Integral Solutions SD", who underwent analysis of genetic material (DNA), which was reported by the Molecular Hemostasis Laboratory in Bonn, Germany. Results: All of these patients were diagnosed with severe hemophilia A with inhibitors; ages ranged between 6 and 48 years, with a median age of 13.5 years. Molecular analysis showed the inversion of intron 22 in six patients (50.0%), a small duplication in two patients (16.7%), the inversion of intron 1 in one patient (8.3%), a large deletion (8.3%), a nonsense mutation (8.3%) and a splice-site (8.3%), findings similar to those of other studies. A total of 58.3% of the patients presented inversion mutations with a high risk of developing inhibitors A total of 83.3% of the evaluated patients presented null mutations; however the presence of high inhibitor titers was 66.7%. The most frequent mutation was the inversion intron 22. Knowing the type of mutation and its association as a risk factor for generating inhibitors invites us to delve into other outcomes such as residual values of coagulation FVIII as well as its impact on the half-life of the exogenous factor applied in prophylaxis.

Variations of sedimentary Fe and Mn fractions under changing lake mixing regimes, oxygenation and land surface processes during Late-glacial and Holocene times.

Global spread of anoxia in aquatic ecosystems has become a major issue that may potentially worsen due to global warming. The reconstruction of long-term hypolimnetic anoxia records can be challenging due to lack of valid and easily measurable proxies. The sedimentary Mn/Fe ratio measured by X-ray fluorescence (XRF) is often used as a proxy for past lake redox conditions. Yet the interpretation of this ratio can be problematic when Fe and Mn accumulation is not solely redox driven. We used the varved sediments of Lake Moossee (Switzerland) to examine the partitioning of Fe and Mn in seven fractions by sequential extraction under various oxygen conditions over the last 15,000 years. We combined this data with XRF scans and an independent diagnostic proxy for anoxia given by a hyperspectral imaging (HSI)-inferred record of bacteriopheophytin, to validate the use of the XRF-Mn/Fe ratio as redox proxy. In the 15,000-year long record, Fe was bound to humins and amorphous, crystalline, sulfide and residual forms. Mn was mainly present in carbonate and amorphous forms. Higher erosion, prolonged anoxia, diagenesis and humic matter input affected Fe and Mn accumulation. Under holomixis the XRF-Mn/Fe ratio successfully reflected lake redox conditions. Periods with higher detrital Fe input obscured the applicability of the ratio. During phases of permanent anoxia, intensified early diagenetic processes trapped Mn in the sediments in carbonate, crystalline oxide and humic forms. Our study shows that the single use of the XRF-Mn/Fe ratio is often not conclusive for inferring past lake redox conditions. The application of the XRF-Mn/Fe as a proxy for anoxia requires taking into account the individual lake characteristics and changes in lake environmental conditions, which affect the accumulation of Fe and Mn in the sediments.

Land Use Affects Carbon Sources to the Pelagic Food Web in a Small Boreal Lake.

Small humic forest lakes often have high contributions of methane-derived carbon in their food webs but little is known about the temporal stability of this carbon pathway and how it responds to environmental changes on longer time scales. We reconstructed past variations in the contribution of methanogenic carbon in the pelagic food web of a small boreal lake in Finland by analyzing the stable carbon isotopic composition (δ13C values) of chitinous fossils of planktivorous invertebrates in sediments from the lake. The δ13C values of zooplankton remains show several marked shifts (approx. 10 ‰), consistent with changes in the proportional contribution of carbon from methane-oxidizing bacteria in zooplankton diets. The results indicate that the lake only recently (1950s) obtained its present state with a high contribution of methanogenic carbon to the pelagic food web. A comparison with historical and palaeobotanical evidence indicates that this most recent shift coincided with agricultural land-use changes and forestation of the lake catchment and implies that earlier shifts may also have been related to changes in forest and land use. Our study demonstrates the sensitivity of the carbon cycle in small forest lakes to external forcing and that the effects of past changes in local land use on lacustrine carbon cycling have to be taken into account when defining environmental and ecological reference conditions in boreal headwater lakes.