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In many Arctic regions, marine coastlines change rapidly in our currently warming climate. In contrast, coastal rock cliffs on Svalbard are considered to be relatively stable. Long-term trends of coastal-retreat rates for rock cliffs on Svalbard remain unknown, but quantifying them could improve our understanding of coastal dynamics in the Canadian Arctic Archipelago. This study presents coastal-retreat rates for rock cliffs along several kilometres of Brøggerhalvøya, Svalbard. The analysis relies on high-resolution orthoimages from 1970, 1990, 2010, and 2021. The data are corroborated by high-precision dGNSS (differential Global Navigation Satellite System) measurements obtained along selected segments of the coastline. Our analysis reveals statistically significant acceleration in coastal-retreat rates across Brøggerhalvøya between 2010 and 2021. The northeast-facing coastline features fairly stable conditions, with retreat rates of 0.04 ± 0.06 m a−1 (1970–1990; calculated retreat rate ± the corresponding measurement uncertainty), 0.04 ± 0.04 m a−1 (1990–2010), and 0.06 ± 0.08 m a−1 (2010–2021). Along the southwest-facing coastline, higher retreat rates of 0.26 ± 0.06 m a−1 (1970–1990), 0.24 ± 0.04 m a−1 (1990–2010), and 0.30 ± 0.08 m a−1 (2010–2021) were calculated. For the most recent decade, this corresponds to an increase of 50 % for the northeast-facing coastline and an increase of 25 % for the southwest-facing coastline. Furthermore, for the northeast-facing coastline, the proportion of the coastline affected by erosion increased from 47 % (1970–1990) to 65 % (2010–2021), while it stayed consistently above 90 % for the southwest-facing coastline. The recent acceleration in retreat rates coincides with increasing storminess and retreating sea ice, factors that can enhance coastal erosion.

Observations of glacier mass changes are key to understanding the response of glaciers to climate change and related impacts, such as regional runoff, ecosystem changes, and global sea level rise. Spaceborne optical and radar sensors make it possible to quantify glacier elevation changes, and thus multi-annual mass changes, on a regional and global scale. However, estimates from a growing number of studies show a wide range of results with differences often beyond uncertainty bounds. Here, we present the outcome of a community-based inter-comparison experiment using spaceborne optical stereo (ASTER) and synthetic aperture radar interferometry (TanDEM-X) data to estimate elevation changes for defined glaciers and target periods that pose different assessment challenges. Using provided or self-processed digital elevation models (DEMs) for five test sites, 12 research groups provided a total of 97 spaceborne elevation-change datasets using various processing approaches. Validation with airborne data showed that using an ensemble estimate is promising to reduce random errors from different instruments and processing methods but still requires a more comprehensive investigation and correction of systematic errors. We found that scene selection, DEM processing, and co-registration have the biggest impact on the results. Other processing steps, such as treating spatial data voids, differences in survey periods, or radar penetration, can still be important for individual cases. Future research should focus on testing different implementations of individual processing steps (e.g. co-registration) and addressing issues related to temporal corrections, radar penetration, glacier area changes, and density conversion. Finally, there is a clear need for our community to develop best practices, use open, reproducible software, and assess overall uncertainty to enhance inter-comparison and empower physical process insights across glacier elevation-change studies.

Abstract Among marine ecosystems globally, those in the Mediterranean Sea, are facing many threats. New technologies are crucial for enhancing our understanding of marine habitats and ecosystems, which can be complex and resource-intensive to analyse using traditional techniques. We tested, for the first time, an integrated multi-platform approach for mapping the coastal benthic habitat in the Civitavecchia (northern Latium, Italy) coastal area. This approach includes the use of an Unmanned Surface Vehicle (USV), a Remote Operated Vehicle (ROV), and in situ measurements of ecosystem functionality. The echosounder data allowed us to reconstruct the distribution of bottom types, as well as the canopy height and coverage of the seagrass Posidonia oceanica. Our study further involved assessing the respiration (Rd) and net primary production (NCP) rates of P. oceanica and its associated community through in situ benthic chamber incubation. By combining these findings with the results of USV surveys, we were able to develop a preliminary spatial distribution model for P. oceanica primary production (PP-SDM). The P. oceanica PP-SDM was applied between the depths of 8 and 10 m in the studied area and the obtained results showed similarities with other sites in the Mediterranean Sea. Though in the early stages, our results highlight the significance of multi-platform observation data for a thorough exploration of marine ecosystems, emphasizing their utility in forecasting biogeochemical processes in the marine environment.

We show a long-term erosion monitoring of several geomorphologically active gully systems on Little Ice Age lateral moraines in the European Central–Eastern Alps, covering a total time period from 1953 to 2019 and including several survey periods in order to identify corresponding morphodynamic trends. For the implementation, DEM (digital elevation model) of Differences (DoDs) were calculated, based on multitemporal high-resolution digital elevation models from historical aerial images (generated by structure from motion photogrammetry with multi-view stereo) and light detection and ranging from airborne platforms. Two approaches were implemented to achieve the corresponding objectives. First, by calculating linear regression models using the accumulated sediment yield and the corresponding catchment area (on a log–log scale), the range of the variability in the spatial distribution of erosion values within the sites. Second, we use volume calculations to determine the total and the mean sediment yield (as well as erosion rates) of the entire sites. Subsequently, both the sites and the different time periods of both approaches are compared. Based on the slopes of the calculated regression lines, it can be shown that the highest variability in the sediment yield at the sites occurs in the first time period (mainly 1950s to 1970s). This can be attributed to the fact that within some sites the sediment yield per square metre increases clearly more strongly (regression lines with slopes up to 1.5). In contrast, in the later time periods (1970s to mid-2000s and mid-2000s to 2017/2019), there is generally a decrease in 10 out of 12 cases (regression lines with slopes around 1). However, even at sites with an increase in the variability in the sediment yield over time, the earlier high variabilities are no longer reached. This means that the spatial pattern of erosion in the gully heads changes over time as it becomes more uniform. Furthermore, using sediment volume calculations and corresponding erosion rates, we show a generally decreasing trend in geomorphic activity (amount of sediment yield) between the different time periods in 10 out of 12 sites, while 2 sites show an opposite trend, where morphodynamics increase and remain at the same level. Finally, we summarise the results of long-term changes in the morphodynamics of geomorphologically active areas on lateral moraines by presenting the “sediment activity concept”, which, in contrast to theoretical models, is based on actually calculated erosion. The level of geomorphic activity depends strongly on the characteristics of the sites, such as size, slope length, and slope gradient, some of which are associated with deeply incised gullies. It is noticeable that especially areas with influence of dead ice over decades in the lower slope area show high geomorphic activity. Furthermore, we show that system internal factors, as well as the general paraglacial adjustment process, have a greater influence on long-term morphodynamics than changing external weather and climate conditions, which, however, had a slight impact mainly in the last, i.e. most recent, time period (mid-2000s to 2017/2019) and may have led to an increase in erosion at the sites.

Subject to a long research tradition, the tree line is considered an important biogeographic indicator of climate changes and associated range shifts. Realized tree line positions and the potential tree line isotherm are, however, rarely in equilibrium because trees are unable to track rapid temperature variations. Often ignored in tree line research, this dilemma constrains the suitability of tree line trees for understanding alpine vegetation responses to anthropogenic warming. Here, we present combined dendrochronological and wood anatomical assessments of 1,351 seedlings and saplings from three subalpine forest species—larch (Larix decidua Mill.), pine (Pinus cembra L.), and spruce (Picea abies)—collected between ~2,200 and 2,600 m.a.s.l. in the Swiss Alps. We found evidence for temperature-induced, pulse-like seedling germination, rather than a continuous, long-term upward movement. Though the species spread across overlapping elevational ranges, larch was found at the highest elevations, followed by spruce and pine. Surprisingly, we found a varying age structure, with no sign of decreasing age toward higher elevations. Spring and summer temperatures promoted germination pulses, but postgermination survival was likely facilitated by species-specific plant traits. Our study demonstrates the importance of seedling and sapling data from above the tree line to understand prevailing vegetation dynamics at cold temperature extremes and also suggests future tree line advancement in the Swiss Alps.

Chlorophyll-a (Chl-a) and Total Suspended Matter (TSM) are key health indicators of the coastal ocean and seas. The former is linked to primary productivity, while the latter is associated with water quality; both are influenced by change in climate. Recent studies have highlighted a declining trend in Chl-a levels along the Mediterranean coastal region. River discharge plays an important role in regulating the coastal Chl-a concentration levels. The present research primarily focuses on understanding the significance of Tiber River −driven spatial dynamics of Chl-a and TSM along the central Tyrrhenian Sea coasts. The research also focuses on evaluating the applicability of Sentinel-2 and identifying a suitable method for estimating Chl-a and TSM from Sentinel-2. Neural networks and dark spectrum fitting techniques were applied using multiple algorithms to estimate the dynamic distribution of Chl-a and TSM driven by the Tiber River in the study area. Multiple statistical analyses were performed, and statistically significant relationships were observed. The Case-2 Regional Coast Colour Neural Network (C2RCC-Net) outperformed all other algorithms, with an R2 value of 0.903 for Chl-a and an R2 value of 0.966 for TSM. Furthermore, the present research also identified a positive pixel to pixel spatial correlation between Chl-a and TSM in all four seasons, highlighting the positive impact of Tiber River on maintaining Chl-a levels along the coasts of Tyrrhenian Sea. This stands in contrast with the negative trend seen in the Mediterranean scale.

Climate change and the associated glacier retreat lead to considerable enlargement and alterations of the proglacial systems. The colonisation of plants in this ecosystem was found to be highly dependent on terrain age, initial site conditions and geomorphic disturbances. Although the explanatory variables are generally well understood, there is little knowledge on their collinearities and resulting influence on proglacial primary succession. To develop a sphere-spanning understanding of vegetation development, a more interdisciplinary approach was adopted. In the proglacial areas of Fürkeleferner, Zufallferner and Langenferner (Martell Valley, Eastern Italian Alps), in total 65 plots of 5×2 m were installed to perform the vegetation analysis on vegetation cover, species number and species composition. For each of those, 39 potential explanatory variables were collected, selected through an extensive literature review. To analyse and further avoid multicollinearities, 33 of the explanatory variables were clustered via principal component analysis (PCA) to five components. Subsequently, generalised additive models (GAMs) were used to analyse the potential explanatory factors of primary succession. The results showed that primary succession patterns were highly related to the first component (elevation and time), the second component (solar radiation), the third component (soil chemistry), the fifth component (soil physics) and landforms. In summary, the analysis of all explanatory variables together provides an overview of the most important influencing variables and their interactions; thus it provides a basis for the debate on future vegetation development in a changing climate.

Abstract Background High grade serous ovarian cancer (HGSOC) is highly lethal, partly due to chemotherapy resistance and limited availability of targeted approaches. Cyclin dependent kinases 12 and 13 (CDK12/13) are promising therapeutic targets in human cancers, including HGSOC. Nevertheless, the effects of their inhibition in HGSOC and the potential synergy with other drugs are poorly known. Methods We analyzed the effects of the CDK12/13 inhibitor THZ531 in HGSOC cells and patient-derived organoids (PDOs). RNA sequencing and quantitative PCR analyses were performed to identify the genome-wide effects of short-term CDK12/13 inhibition on the transcriptome of HGSOC cells. Viability assays with HGSOC cells and PDOs were performed to assess the efficacy of THZ531 as single agent or in combination with clinically relevant drugs. Results The CDK12 and CDK13 genes are deregulated in HGSOC and their concomitant up-regulation with the oncogene MYC predicts poor prognosis. HGSOC cells and PDOs display high sensitivity to CDK12/13 inhibition, which synergizes with drugs in clinical use for HGSOC. Transcriptome analyses revealed cancer-relevant genes whose expression is repressed by dual CDK12/13 inhibition through impaired splicing. Combined treatment with THZ531 and inhibitors of pathways regulated by these cancer relevant genes (EGFR, RPTOR, ATRIP) exerted synergic effects on HGSOC PDO viability. Conclusions CDK12 and CDK13 represent valuable therapeutic targets for HGSOC. We uncovered a wide spectrum of CDK12/13 targets as potential therapeutic vulnerabilities for HGSOC. Moreover, our study indicates that CDK12/13 inhibition enhances the efficacy of approved drugs that are already in use for HGSOC or other human cancers.

Alpine rivers have experienced considerable changes in channel morphology over the last century. Natural factors and human disturbance are the main drivers of changes in channel morphology that modify natural sediment and flow regimes at local, catchment, and regional scales. In glaciated catchments, river sediment loads are likely to increase due to increasing snowmelt and glacier melt runoff, facilitated by climate change. Additionally, channel erosion and depositional dynamics and patterns are influenced by sediment delivery from hillslopes and sediment in the forefields of retreating glaciers. In order to reliably assess the magnitudes of the channel-changing processes and their frequencies due to recent climate change, the investigation period needs to be extended to the last century, ideally back to the end of the Little Ice Age. Moreover, a high temporal resolution is required to account for the history of changes in channel morphology and for better detection and interpretation of related processes. The increasing availability of digitised historical aerial images and advancements in digital photogrammetry provide the basis for reconstructing and assessing the long-term evolution of the surface, in terms of both planimetric mapping and the generation of historical digital elevation models (DEMs). The main issue of current studies is the lack of information over a longer period. Therefore, this study contributes to research on fluvial sediment changes by estimating the sediment balance of a main Alpine river (Fagge) in a glaciated catchment (Kaunertal, Austria) over 19 survey periods from 1953 to 2019. Exploiting the potential of historical multi-temporal DEMs combined with recent topographic data, we quantify 66 years of geomorphic change within the active floodplain, including erosion, deposition, and the amounts of mobilised sediment. Our study focuses on a proglacial river that is undergoing a transition phase, resulting from an extensive glacier retreat of approximately 1.8 km. This has led to the formation of new channel networks and an overall negative cumulative sediment balance for the entire study area. We found that high-magnitude meteorological and hydrological events associated with local glacier retreats have a significant impact on the sediment balance. The gauge record indicates an increase in such events, as well as in runoff and probably in sediment transport capacity. Despite this, the sediment supply has declined in the last decade, which can be attributed to a lower contribution of the lateral moraines coupled to the channel network and less sediment sourced from the melting Gepatsch Glacier as evidenced by roches moutonnées exposed in the current/most recent forefield. Nonetheless, we observed significant erosion in the tributary, leading to the transport of sediment downstream. Overall, this study enhances our understanding of the complexity of sediment dynamics in proglacial rivers across various spatial and temporal scales and their relationship to climate change factors.

Social Impact Statement Botanic gardens offer unique opportunities for unravelling responses of plant life to climate change. Despite investigations into their aboveground sphere, the belowground realm is usually neglected. Cambridge University Botanic Garden now illuminates the hidden world of one of the most sought‐after culinary delicacies—the Burgundy truffle. The garden's plant diversity, the serendipity of a truffle dog, and our curiosity‐driven research agenda reveal insights into 278 truffle fruitbodies that grew symbiotically with an unusually high number of host species. Our study reinforces the power of botanic gardens to disentangle ecosystem processes and emphasizes the proximity of scientific and public interests in truffles.

Cancer-associated fibroblasts (CAFs) are the main component of the stroma in pancreatic cancer, but their tissue of origin remains to be defined. Here the authors perform lineage tracing and single cell RNA sequencing in mice and suggest the splanchnic mesenchyme as the tissue of origin for CAFs.

Among the four endometrial cancer (EC) TCGA molecular groups, the MSI/hypermutated group represents an important percentage of tumors (30%), including different histotypes, and generally confers an intermediate prognosis for affected women, also providing new immunotherapeutic strategies. Immunohistochemistry for MMR proteins (MLH1, MSH2, MSH6 and PMS2) has become the optimal diagnostic MSI surrogate worldwide. This review aims to provide state-of-the-art knowledge on MMR deficiency/MSI in EC and to clarify the pathological assessment, interpretation pitfalls and reporting of MMR status.

Abstract More than 200 years after von Humboldt’s pioneering work on the treeline, our understanding of the cold distribution limit of upright plant growth is still incomplete. Here, we use wood anatomical techniques to estimate the degree of stem cell wall lignification in 1770 plant species from six continents. Contrary to the frequent belief that small plants are less lignified, we show that cell wall lignification in ‘woody’ herbs varies considerably. Although trees and shrubs always exhibit lignified cell walls in their upright stems, small plants above the treeline may contain less lignin. Our findings suggest that extremely cold growing season temperatures can reduce the ability of plants to lignify their secondary cell walls. Corroborating experimental and observational evidence, this study proposes to revisit existing theories about the thermal distribution limit of upright plant growth and to consider biochemical and biomechanical factors for explaining the global treeline position.

In the Karakoram, dozens of glacier surges occurred in the past 2 decades, making the region a global hotspot. Detailed analyses of dense time series from optical and radar satellite images revealed a wide range of surge behaviour in this region: from slow advances longer than a decade at low flow velocities to short, pulse-like advances over 1 or 2 years with high velocities. In this study, we present an analysis of three currently surging glaciers in the central Karakoram: North and South Chongtar Glaciers and an unnamed glacier referred to as NN9. All three glaciers flow towards the same small region but differ strongly in surge behaviour. A full suite of satellites (e.g. Landsat, Sentinel-1 and 2, Planet, TerraSAR-X, ICESat-2) and digital elevation models (DEMs) from different sources (e.g. Shuttle Radar Topography Mission, SRTM; Satellite Pour l’Observation de la Terre, SPOT; High Mountain Asia DEM, HMA DEM) are used to (a) obtain comprehensive information about the evolution of the surges from 2000 to 2021 and (b) to compare and evaluate capabilities and limitations of the different satellite sensors for monitoring surges of relatively small glaciers in steep terrain. A strongly contrasting evolution of advance rates and flow velocities is found, though the elevation change pattern is more similar. For example, South Chongtar Glacier had short-lived advance rates above 10 km yr−1, velocities up to 30 m d−1, and surface elevations increasing by 170 m. In contrast, the neighbouring and 3-times-smaller North Chongtar Glacier had a slow and near-linear increase in advance rates (up to 500 m yr−1), flow velocities below 1 m d−1 and elevation increases up to 100 m. The even smaller glacier NN9 changed from a slow advance to a full surge within a year, reaching advance rates higher than 1 km yr−1. It seems that, despite a similar climatic setting, different surge mechanisms are at play, and a transition from one mechanism to another can occur during a single surge. The sensor inter-comparison revealed a high agreement across sensors for deriving flow velocities, but limitations are found on small and narrow glaciers in steep terrain, in particular for Sentinel-1. All investigated DEMs have the required accuracy to clearly show the volume changes during the surges, and elevations from ICESat-2 ATL03 data fit neatly to the other DEMs. We conclude that the available satellite data allow for a comprehensive observation of glacier surges from space when combining different sensors to determine the temporal evolution of length, elevation and velocity changes.

Defining plant development timing through seasonal growth and dormancy phases is a valuable proxy for studying climate change and serves as an annual bioindicator. However, current methods for determining the growing season vary due to species‐specific interpretations and differing understandings of its main drivers. Körner et al. (2023) introduced four non‐interchangeable definitions of growing seasons to clarify this complex issue. While some studies have paired different methods, none have simultaneously applied a full set of methods at the individual tree or species level. Here, I aim to present a new perspective to understanding growing season timing by focusing on all facets of above‐ground tree growth and measurable biological and phenological markers. This approach calls for simultaneous, continuous monitoring during active and dormancy periods on the same trees and across different species at a large spatial scale. The goal is to comprehensively understand each method's errors, temporal lags, and the factors determining each growing season, as defined by Körner et al. (2023, Ecology Letters, 26, 1277). Accurate estimation of growing season timing can reshape our understanding of its environmental drivers, improve terrestrial ecosystem models, assess the impact of climate change on tree growth, determine the biological zero for various species, verify remote sensing indices and forecast species distribution. [ABSTRACT FROM AUTHOR]

In locally advanced cervical cancer (LACC), definitive chemo-radiotherapy is the standard treatment, but chemo-radiotherapy followed by surgery could be an alternative choice in selected patients. We enrolled 244 patients affected by LACC and treated with CT-RT followed by surgery in order to assess the prognostic role of the histological response using the Mandard scoring system. Results: A complete pathological response (TRG 0) was observed in 118 patients (48.4%), rare residual cancer cells (TRG2) were found in 49 cases (20.1%), increased number of cancer cells but fibrosis still predominating (TRG3) in 35 cases (14.3%), and 42 (17.2%) were classified as non-responders (TRG4–5). TRG was significantly associated with both OS (p < 0.001) and PFS (p < 0.001). The survival curves highlighted two main prognostic groups: TRG1-TRG2 and TRG3-TRG4–5. Main responders (TRG1–2) showed a 92% 5-year overall survival (5y-OS) and a 75% 5-year disease free survival (5y-DFS). Minor or no responders showed a 48% 5y-OS and a 39% 5y-DFS. The two-tiered TRG was independently associated with both DFS and OS in Cox regression analysis. Conclusion. We showed that Mandard TRG is an independent prognostic factor in post-CT/RT LACC, with potential benefits in defining post-treatment adjuvant therapy.

Permafrost is being degraded worldwide due to the change in external forcing caused by climate change. This has also been shown to affect the morphodynamics of active rock glaciers. We studied these changes, depending on the analysis, on nine or eight active rock glaciers, respectively, with different characteristics in multiple epochs between 1953 and 2017 in Kaunertal, Austria. A combination of historical aerial photographs and airborne laser scanning data and their derivatives were used to analyse surface movement and surface elevation change. In general, the studied landforms showed a significant acceleration of varying magnitude in the epoch 1997–2006 and a volume loss to variable degrees throughout the investigation period. Rock glaciers related to glacier forefields showed significantly higher rates of subsidence than talus-connected ones. Besides, we detected two rock glaciers with deviating behaviour and one that showed an inactivation of its terminal part. By analysing meteorological data (temperature, precipitation and snow cover onset and duration), we were able to identify possible links to these external forcing parameters. The catchment-wide survey further revealed that, despite the general trend, timing, magnitude and temporal peaks of morphodynamic changes indicate a slightly different sensitivity, response or response time of individual rock glaciers to fluctuations and changes in external forcing parameters.