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Wetland sediments are valuable archives of environmental change but can be challenging to date. Terrestrial macrofossils are often sparse, resulting in radiocarbon (14C) dating of less desirable organic fractions. An alternative approach for capturing changes in atmospheric 14C is the use of terrestrial microfossils. We 14C date pollen microfossils from two Australian wetland sediment sequences and compare these to ages from other sediment fractions (n = 56). For the Holocene Lake Werri Berri record, pollen 14C ages are consistent with 14C ages on bulk sediment and humic acids (n = 14), whilst Stable Polycyclic Aromatic Carbon (SPAC) 14C ages (n = 4) are significantly younger. For Welsby Lagoon, pollen concentrate 14C ages (n = 21) provide a stratigraphically coherent sequence back to 50 ka BP. 14C ages from humic acid and >100 µm fractions (n = 13) are inconsistent, and often substantially younger than pollen ages. Our comparison of Bayesian age-depth models, developed in Oxcal, Bacon and Undatable, highlight the strengths and weaknesses of the different programs for straightforward and more complex chrono-stratigraphic records. All models display broad similarities but differences in modeled age-uncertainty, particularly when age constraints are sparse. Intensive dating of wetland sequences improves the identification of outliers and generation of robust age models, regardless of program used.

Ablation of atrial fibrillation (AF) with high-power-short-duration (HPSD) radiofrequency (RF) technology is emerging as a new standard of care in many electrophysiology laboratories. While procedural short-term efficacy and efficiency is very promising, little is known about mid- to long-term effects of HPSD ablation for pulmonary vein isolation (PVI) and left atrial substrate modification.In a single-center registry, 412 AF procedures were performed in 400 individual patients using a standardized CLOSE protocol-guided fixed 50 W HPSD ablation, aiming for an ablation index (AI) of 400 on the posterior and 550 on the anterior wall. Additional substrate-tailored lines were performed when required.After a mean clinical follow-up of 337 ± 134 days, 15 patients suffered from AF recurrence beyond the blinding period. Twelve gave consent to the indicated reablation. Here, 11 of 12 patients had chronic isolation of all four pulmonary veins (PV). In three of six patients, a reconnection of additional left atrial ablation lines was revealed. Ten out of 12 patients showed progressive fibrous atrial cardiomyopathy and required additional left atrial substrate modification or reisolation of left-atrial lines. During the follow-up no clinical case of atrioesophageal fistula was registered. No PV stenosis after initial HPSD PVI was documented.Patients requiring reablation of AF or other atrial tachycardia after a fixed 50 W HPSD circumferential PVI and substrate modification predominantly suffer from progressive fibrous atrial cardiomyopathy, while PV reconnection appears to be a rare cause of AF recurrence.

Perovskite oxides of the general formula ABO

INTRODUCTION Ablation index (AI)-guided ablation according to the CLOSE protocol is very effective in terms of chronic pulmonary vein isolation (PVI). However, the optimal radiofrequency (RF) power remains controversial. Here, we thought to investigate the efficiency and safety of an AI-guided fixed circumferential 50 W high-power short-duration (HPSD) PVI using the CLOSE protocol. METHODS AND RESULTS In a single-center trial, 40 patients underwent randomized PVI using AI-guided ablation without esophageal temperature monitoring. In 20 patients a CLOSE protocol guided fixed 50 W HPSD was followed irrespective of the anatomical localization. Twenty subjects were treated according to the CLOSE protocol with standard power settings (20 W posterior and 40 W roof and anterior wall). In addition, 80 consecutive patients were treated according to the HPSD protocol to gather additional safety data. All patients underwent postprocedural esophagogastroduodenoscopy to reveal esophageal lesions (EDELs). The mean total procedural time was 80.3 ± 22.5 in HPSD compared to control 109.1 ± 27.4 min (p

Pulmonary vein isolation (PVI) using high-power-short-duration (HPSD) radiofrequency ablation (RF) is emerging as the standard of care for treatment of atrial fibrillation (AF). While procedural short-term to midterm efficacy and efficiency are very promising, this registry aims to investigate esopahgeal safety using an optimized ablation approach.In a single-center experience, 388 consecutive standardized first-time AF ablation were performed using a CLOSE-guided-fixed-50 W-circumferential PVI and substrate modification without intraprocedural esophageal temperature measurement. Three hundred patients underwent postprocedural esophageal endoscopy to diagnose and grade endoscopically detected esophageal lesions (EDEL) and were included in the analysis.EDEL were detected in 35 of 300 patients (11.6%), 25 of 35 were low-grade Kansas-city-classification (KCC) 1 lesions with fast healing tendencies. Six patients suffered KCC 2a lesions, 4 patients had KCC 2b lesions (1.3% of all patients). No esophageal perforation or fistula formation was observed. Patient baseline characteristics, especially patients age, gender, and body mass index did not influence EDEL incidence. Additional posterior box isolation did not increase the incidence of EDEL. In patients diagnosed with EDEL, mean catheter contact force during posterior wall ablation was higher (11.9 ± 1.8 vs. 14.7 ± 3 g, p .001), mean RF duration was shorter (11.9 ± 1 vs. 10.7 ± 1.2 s, p .001), while achieved ablation index was not different between groups (434 ± 4.9 vs. 433 ± 9.5, n.s.).Incidence of EDEL after CLOSE-guided-50 W-HPSD PVI is lower compared to historical cohorts using standard-power RF settings. Catheter contact force during posterior HPSD ablation should not exceed 15 g.

In this study, we describe the synthesis and biological evaluation of a set of bis‐3‐chloropiperidines (B−CePs) containing rigid aromatic linker structures. A modification of the synthetic strategy also enabled the synthesis of a pilot tris‐3‐chloropiperidine (Tri‐CeP) bearing three reactive meta‐chloropiperidine moieties on the aromatic scaffold. A structure–reactivity relationship analysis of B−CePs suggests that the arrangement of the reactive units affects the DNA alkylating activity, while also revealing correlations between the electron density of the aromatic system and the reactivity with biologically relevant nucleophiles, both on isolated DNA and in cancer cells. Interestingly, all aromatic 3‐chloropiperidines exhibited a marked cytotoxicity and tropism for 2D and 3D cultures of pancreatic cancer cells. Therefore, the new aromatic 3‐chloropiperidines appear to be promising contenders for further development of mustard‐based anticancer agents aimed at pancreatic cancers., As keen as mustard: Aromatic 3‐chloropiperidines designed to improve the therapeutic potential of mustard‐based DNA alkylating agents have been synthesized and evaluated. These small molecules exhibited a marked anti‐proliferative effect preferentially against BxPC‐3 pancreatic adenocarcinoma cells in 2D and 3D cultures, thus demonstrating themselves to be promising candidates for the further development of sustainable chemotherapeutics active against pancreatic tumors.

The Quaternary is characterized by a series of glacial-interglacial cycles and a shift in the Earth's climate state known as the mid-Pleistocene Transition (MPT, ca. 1200 ka to 720 ka). The progressive increase in glacial cycle length from approximately 41 ka to on average 100 ka affected marine and terrestrial life, but how it affected freshwater communities is far less known. Here, diatom and paleoenvironmental data between 1050 ka and 815 ka from a sediment succession of ancient Lake Ohrid are used to understand how the freshwater communities responded to environmental changes during key-periods of glacial intensification associated with the MPT. Based on stratigraphically constrained incremental sum of squares cluster (CONISS), a distinct diatom community turnover in Lake Ohrid was identified during the study period. The first community existed between 1050 and 955 ka MIS (Marine Isotope Stages) 30–25 and was mostly influenced by environmental parameters related to nutrient supply, mixing processes and primary productivity in the lake. The second community existed between 955 and 815 ka (MIS 25–21) and was largely driven by ontogenetic processes related to the ongoing deepening of the lake, changes in bottom water redox conditions and changes in mixing processes in the lake. The increased severity and duration of cold, glacial stages during the MPT shows only a weak impact on the diatom community in Lake Ohrid. Shifts in species phenotypes, abundance and composition are found in both communities, likely as adaptation in response to the changing environmental conditions. This study shows that the diatom communities were only weakly affected by the progressive intensification of the glacial intensity during the MPT, emphasizing the role of local environmental changes in regulating freshwater communities.

There is still a paucity of hydrological data explaining the relationship between (rapid, millennial‐scale) climate forcing and Mediterranean rainfall since the Last Glacial. We show that distinct lake‐level fluctuations at Lake Trasimeno (Italy) are associated with changing aridity in the central Mediterranean during the last ~47 800 years. The lake‐level fluctuations are reconstructed based on carbonate mineral content and carbonate mineral species, as well as the stable oxygen and carbon isotope (δ18O and δ13C) geochemistry of endogenic carbonates. Low lake levels are linked to high carbonate, Mg‐calcite and aragonite contents, and high δ18O and δ13C values. Inferred hydrological changes are linked to glacial–interglacial and, tentatively within the limitations of our chronology, to millennial‐scale climate variability as well as the intensity of the Atlantic Meridional Overturning Circulation (AMOC). Prior to the Last Glacial Maximum (LGM), during intervals equivalent to Marine Isotope Stage 3 (MIS 3), a stronger AMOC associated with Greenland interstadial periods (Dansgaard/Oeschger (D/O) warm periods) and stronger Asian monsoon probably coincide with increased precipitation in central Italy as inferred from high lake levels at Lake Trasimeno. Periods of weak AMOC intensity such as during Greenland stadials (D/O cold periods), during Heinrich events, and weak Asian monsoons are correlated with lake level lowstands, which imply relatively dry conditions in central Italy. Lake Trasimeno’s water level during the LGM and the Lateglacial (MIS 2) is relatively stable, with recorded changes showing distinct similarities to orbital configurations. Although muted, high latitude climate forcing is still evident in the data during peak glacial conditions. The transition from D/O‐like hydrological variability at Lake Trasimeno during MIS 3 to orbitally controlled fluctuations during the Lateglacial to Holocene transition coincides with an increasing amplitude in local winter and summer insolation, probably indicating increasing seasonality and a larger temperature gradient between low‐ and high‐latitude settings., Deutscher Akademischer Austauschdienst http://dx.doi.org/10.13039/501100001655

Background: The cause of worsened clinical outcome due to high RV pacing burden remains unclear.Objective: To investigate the impact of RV pacing on several echocardiographic and spiroergometric parameter Methods: In 60 pacemaker patients with preserved LVEF serial echocardiographies and spiroergometries were performed over a time course of 12 months. Additionally in 50 patients retrospective echocardiographic analyses of the LV- and RV function were carried out up to 24 months after pacemaker implantation.Results: The patients were divided into two groups: The high RV pacing burden group (hRVP: ≥ 40%) and the low RV pacing group (lRVP Conclusions: In pacemaker patients with preserved LVEF the burden of RV pacing has no adverse influence, neither to several echocardiographic parameters nor to the clinical exercise capacity after a follow-up of 12 to 24 month. Therefore, the mechanism of the worsened clinical outcome due to high RV pacing burden in patients without a relevant structural heart disease remains unclear.

Background The incidence of worsened clinical outcome due to high right ventricular (RV) pacing burden in patients with preserved left ventricular function remains controversial. Objective To investigate the impact of RV pacing on several echocardiographic and spiroergometric parameters. Methods In 60 pacemaker patients with preserved left ventricular ejection fraction (LVEF) serial echocardiographies and spiroergometries were performed over a time course of 12 months. Additionally, in 48 patients retrospective echocardiographic analyses of the LV- and RV function were carried out up to 24 months after pacemaker implantation. Results The patients were divided into two groups: The high RV pacing burden group (hRVP: ≥ 40%) and the low RV pacing group (lRVP Conclusions In pacemaker patients with preserved LVEF the burden of RV pacing has no adverse influence on several echocardiographic and spiroergometric surrogate parameters of pacemaker-induced cardiomyopathy after a follow-up of 12 to 24 month. Despite this, screening for pacemaker induced cardiomyopathy should be performed especially in the presence of new heart failure symptoms.

Background Uninterrupted direct oral anticoagulation (DOAC) in AF‐ablation is recommended, proven by randomized trials. The outcome and the periinterventional differences between DOACs and VKA in the real world clinical practice are discussed controversial. Hypothesis To investigate efficiency and safety of uninterrupted DOAC therapy compared to VKA during AF‐Ablation in real world setting with a focus on periinterventional heparin dosage.

Understanding the evolution of soil systems on geological time scales has become fundamentally important to predict future landscape development in light of rapid global warming and intensifying anthropogenic impact. Here, we use an innovative uranium isotope-based technique combined with organic carbon isotopes and elemental ratios of sediments from Lake Ohrid (North Macedonia/Albania) to reconstruct soil system evolution in the lake's catchment during the last ~16,000 cal yr BP. Uranium isotopes are used to estimated the paleo-sediment residence time, defined as the time elapsed between formation of silt and clay sized detrital matter and final deposition. The chronology is based on new cryptotephra layers identified in the sediment sequence. The isotope and elemental data are compared to sedimentary properties and pollen from the same sample material to provide a better understanding of past catchment erosion and landscape evolution in the light of climate forcing, vegetation development, and anthropogenic land use. During the Late Glacial and the Early Holocene, when wide parts of the catchment were covered by open vegetation, wetter climates promoted the mobilisation of detrital matter with a short paleo-sediment residence time. This is explained by erosion of deeper parts of the weathering horizon from thin soils. Detrital matter with a longer paleo-sediment residence time, illustrating shallow erosion of thicker soils is deposited in drier climates. The coupling between climatic variations and soil erosion terminates at the Early to Mid-Holocene transition as evidenced by a pronounced shift in uranium isotope ratios indicating that catchment erosion is dominated by shallow erosion of thick soils only. This shift suggests a threshold is crossed in hillslope erosion, possibly as a result of a major change in vegetation cover preventing deep erosion of thin soils at higher elevation. The threshold in catchment erosion is not mirrored by soil development over time, which gradually increases in response to Late Glacial to Holocene warming until human land use during the Late Holocene promotes reduced soil development and soil degradation. Overall, we observe that soil system evolution is progressively controlled by climatic, vegetation, and eventually by human land use over the last ~16,000 years.

The endorheic nature of Lake Trasimeno in combination with its position in central Italy makes it a relevant site to better constrain spatial differences in Holocene climatic variability in the Mediterranean area. Herein, we present a high-resolution ostracod record from the Holocene section of an 8.59-m-long sedimentary core, which is compared with historical data to distinguish anthropogenic and climatic signals. The occurrence, abundance and vanishing of ostracod species are directly controlled by lake-level variations, which are in turn related to global and regional climatic changes (i.e. moisture variations). The total organic carbon content as well as observed lithological changes provide additional information about Lake Trasimeno’s hydrological and trophic conditions in the past. Most important variations have been identified at ca. 10,000 cal. yr BP, when the lacustrine basin changed from a temporary to a permanent waterbody (from Sarsicypridopsis aculeata to Candona angulata association). The highest lake level and the total absence of ostracods occur at around 9000 cal. yr BP. The recorded humid phase persisted up to ca. 4200 cal yr BP since when a lake-level decreasing trend started and continued until the present day ( Candona angulata, Cyprideis torosa and Darvinula stevensoni associations). The frequency of changes in the relative abundance of the main species shows centennial variations (i.e. C. angulata, C. torosa and Darvinula stevensoni). As historical evidences yield that human interventions to control the lake level remained unsuccessful in the past, Lake Trasimeno records an almost pristine climatic signal during most of the Holocene, which is quite unusual in the highly populated Mediterranean area.

Introduction: Ablation Index guided ablation according to the CLOSE protocol is very effective in terms of chronic pulmonary vein isolation (PVI). However, the optimal RF power remains controversial. Here, we thought to investigate the efficiency and safety of an AI guided fixed circumferential 50W high power short duration (HPSD) PVI using the CLOSE protocol Methods and results: In a single-centre prospective “proof of concept” trial 40 patients underwent randomized PVI using AI guided RF ablation without oesophageal temperature monitoring. In 20 patient fixed 50W HPSD was used irrespective to the anatomical localization. 20 subjects were ablated with standard power settings (20W posterior and 40W roof and anterior wall). Additionally, 80 consecutive patients were treated according to the HPSD protocol to gather additional safety data. All patients underwent post-procedural oesophago-gastro-duodenoscopy to reveal oesophageal lesions (EDEL). The mean total procedural time was 80.3±22.5 minutes in HPSD compared to control 109.1±27.4 (p

Soil Organic Carbon (SOC) represents with up to 80% the largest part of the terrestrial’s carbon pool. However, it is still highly debated if soil-carbon is a net atmospheric carbon source or sink. This is mainly due to a paucity of information on the SOC’s fate during soil erosion, which controls the interplay between SOC oxidation during soil storage, transportation, and final storage in a sedimentary sink. The southern hemisphere landmasses have the potential to play a dominant role in the SOC - atmosphere carbon cycle, since wetter (dryer) climates can cause the expansion (contraction) of terrestrial biomass in vast continental areas, such as for example in temperate to semi-arid SE Australia.We herein investigate the interplay between catchment erosion (quantified by means of uranium isotopes), vegetation density (pollen), the wetland’s response (diatoms), and catchment-wide carbon and nitrogen cycling (carbon and nitrogen isotopes) on glacial/interglacial time scales in SE Australia. The analyses are applied to the sediments of Lake Couridjah, which is part of the Thirlmere Lake system located approximately 100 km SE of Sydney. A previous study has shown that Lake Couridjah and its catchment vegetation are highly sensitive to local and regional climate change. Radiocarbon and luminescence dating revealed that recovered lake sediments cover the time interval between ~140 ka and 100 ka, and between ~17.6 cal yr BP and present day. Lake Couridjah is thus one of the very few sedimentary archives providing a continuous archive for the previous interglacial complex in SE Australia, and thus offers an outstanding opportunity to study SOC cycling in a small catchment across different interglacial boundary conditions. The sedimentary analyses are supported by uranium, carbon, and nitrogen isotope analyses of a soil pit from the vicinity of the lake.Statistical analyses revealed robust phase-relationships between catchment erosion, vegetation density, and carbon and nitrogen cycling during both glacial-interglacial complexes. The data implies that the density of the catchment’s sclerophyll woodland and mid- to understory vegetation - and not the amount of rainfall - has major control on catchment erosion, and, thus, on SOC storage in the catchment. Overall wetter and warmer peak interglacial conditions promote the expansion of dense sclerophyll vegetation, reducing catchment erosion while simultaneously increasing SOC storage as well as lake productivity and lake carbon-storage. The later post-Eemian phase of the preceding interglacial reveals overall cooler climates and a more open sclerophyll vegetation, resulting in faster catchment-wide erosion and reduced SOC and lake-C storage, conditions that are amplified in glacial periods (post-LGM, penultimate glacial period).

Nitrogen mustards (NMs) are an old but still largely diffused class of anticancer drugs. However, spreading mechanisms of resistance undermine their efficacy and therapeutic applicability. To expand their antitumour value, we developed bis‐3‐chloropiperidines (B‐CePs), a new class of mustard‐based alkylating agent, and we recently reported the striking selectivity for BxPC‐3 pancreatic tumour cells of B‐CePs bearing aromatic moieties embedded in the linker. In this study, we demonstrate that such tropism is shared by bis‐3‐chloropiperidines bearing appended aromatic groups in flexible linkers, whereas esters substituted by aliphatic groups or by efficient DNA‐interacting groups are potent but nonselective cytotoxic agents. Besides, we describe how the critical balance between water stability and DNA reactivity can affect the properties of bis‐3‐chloropiperidines. Together, these findings support the exploitation of B‐CePs as potential antitumour clinical candidates., Balancing act: Following our development of bis‐3‐chloropiperidines (B‐CePs), a new class of sustainable mustard‐based alkylating agents, we demonstrate that B‐CePs bearing appended aromatic groups in linkers show tropism toward pancreatic tumour models. In addition, we describe how the critical balance between DNA reactivity and water stability can affect the properties of this class of compounds.

Understanding and quantifying the processes and geochemical cycles associated with catchment erosion, the development of soils and weathering horizons, and terrestrial habitat change beyond the scales of modern observations remain challenging. Such research, however, has become increasingly important to help predict future landscape change in light of increasing land use and rapid global warming. We herein review organic and inorganic geochemical tools applied to depositional archives to better understand various aspects of landscape evolution on geological time scales. We highlight the potentials and limitations of inorganic geochemical analytical methods, such as major element geochemistry, metal and radiogenic isotopes, and in-situ cosmogenic nuclides, as qualitative, semi-quantitative, and quantitative proxies for the transformation of bedrock material via regolith and soils to sediments. We also show how stable isotope geochemistry applied to lacustrine endogenic carbonates can be used to infer rock-water interactions, vegetation change, and soil development in limestone-rich catchments. Proxies focusing on the silicilastic element of sediment formation, transport and deposition are ideally combined with organic geochemical proxies for vegetation change and soil organic matter evolution in a catchment to gain a comprehensive picture of the Critical Zone’s evolution over time. Multi-proxy and multidisciplinary research combining organic and inorganic geochemical techniques from several sedimentary archives in the same catchment have high potential to provide comprehensive information on Quaternary landscape evolution and thus improve the robustness of associated forecasting models.

Evidence for global environmental and climate change-related loss of biodiversity is accumulating. Understanding the causes of species community change is thus essential for effective management and conservation policies. Nonetheless, disentangling the relative influence of the individual or multiple drivers determining the species communities is challenging, as ecosystems are simultaneously affected by variable drivers acting on different spatial and temporal scales. To this end, paleolimnological data may provide critical information on long-term community changes, species dominance shifts, and their underlying drivers. Natural forced changes in the aquatic environments can be used to study the response of biota to repeated fluctuations in essential key variables. In this study, we investigated the planktonic diatom communities in a continuous, 1.36 Ma sedimentary succession from ancient Lake Ohrid (North Macedonia/Albania). This is the oldest, continuously existing freshwater lake in Europe, acknowledged as a site of exceptional biodiversity and endemic species richness. An extended biogeochemical dataset from the DEEP site sedimentary record and previously-published variables representing global climate variability was used to: i) quantify the relative influence of individual environmental variables in governing species communities, and ii) disentangle the contribution of basin-scale environmental processes and global-scale climate variability in driving community patterns over time. The results show that the structure of planktonic communities was primarily determined by the basin-scale environment, particularly, nutrient availability, water temperature and water column mixing, but also local tectonic processes, since lake ontogeny. However, since the onset of the penultimate glacial period 0.185 Ma ago, global-scale climate variability became the principal drivers of the diatom community structure. Our proxy time-series illustrates how various factors at different spatial scales may determine the freshwater planktonic communities over geological time-scales. Extended periods of stable communities can be terminated by changes in climate, environmental conditions and/or lake ontogeny, leading to species extinctions and community turnovers. Thereby lake ecosystem structure and functioning are affected and effective management and conservation policies are required to minimize additional anthropogenic change-related loss of biodiversity.

This study presents, for the first time, a detailed quantitative reconstruction of winter (January) and summer (July) palaeotemperatures from the Late Pleistocene to Holocene transition in central Italy based on ostracod assemblages in an 8.59-m-long sediment core retrieved in Lake Trasimeno. Of 19 ostracod species recovered, 13 were calibrated according to their living temperature ranges, enabling us to reconstruct mean January and July temperature ranges using the mutual ostracod temperature range (MOTR) method. The occurrences of Cytheromorpha fuscata and Limnocythere suessenbornensis from 44000 to 25500cal. a BP showed mean January temperatures at least 7°C colder and mean July temperature at least 1°C cooler in some intervals compared to present-day temperatures. Comparison of the MOTR-derived January minima curve with a Greenland oxygen isotope record (NGRIP) shows a remarkable correlation of warmer Greenland Interstadial and the colder Greenland Stadial events with clear peaks and troughs in the MOTR signal. These correlations were tested successfully by tuning the MOTR curve to the NGRIP record, resulting in an improved age-depth model combining radiocarbon ages with MOTR tie points. The results demonstrate that a record of rapid climate change in the North Atlantic region is archived in lacustrine ostracod assemblages in central Italy.

Sclerochronological data from whole bivalve shells have been used extensively to derive palaeoenvironmental information. However, little is known about the relevance of shell fragments more commonly preserved in the sediment record. Here, we investigate the oxygen and carbon isotope composition of Dreissena carinata fragments from a core recovered from Lake Dojran (FYRO Macedonia/Greece) to identify their relevance and efficacy as a proxy in palaeoenvironmental studies. We use a modern Dreissena shell to calibrate the relationship between the bivalve and its contemporary environment, which suggests their isotope composition is primarily a function of temperature and water balance. The range of fragment isotope data from the core overlaps with that of unbroken fossil shells, suggesting the fragments broadly record lakewater conditions across the time of deposition. A comparison of the isotope composition of shell fragments and endogenic carbonate shows an offset between the two sets of data, which is likely due to temperature differences between surface and bottom waters, the timing of carbonate precipitation, and productivity-controlled stratification of the dissolved inorganic carbon pool. Shell fragment isotope data seem to reflect the signal of environmental change recorded in other proxy data from the same core and may potentially be used (like endogenic carbonate) to provide information on past changes in lake level.

A new high-resolution pollen and NPP (non-pollen palynomorph) analysis has been performed on the sediments of Lake Dojran, a transboundary lake located at the border between Greece and the former Yugoslav Republic of Macedonia (FYROM). The sequence covers the last 12 500 years and provides information on the vegetational dynamics of the Late Glacial and Holocene for the southern Balkans. Robust age model, sedimentological diatom, and biomarker analyses published previously have been the base for a multi-perspective interpretation of the new palynological data. Pollen analysis revealed that the Late Glacial is characterized by steppic taxa with prevailing Amaranthaceae, Artemisia and Poaceae. The arboreal vegetation starts to rise after 11 500 yr BP, taking a couple of millennia to be definitively attested. Holocene vegetation is characterized by the dominance of mesophilous plants. The Quercus robur type and Pinus are the most abundant taxa, followed by the Quercus cerris type, the Quercus ilex type and Ostrya–Carpinus orientalis. The first attestation of human presence can be presumed at 5000 yr BP from the contemporary presence of cereals, Juglans and Rumex. A drop in both pollen concentration and influx together with a δ18Ocarb shift indicates increasing aridity and precedes clear and continuous human signs since 4000 yr BP. Also, a correlation between Pediastrum boryanum and fecal stanol suggests that the increase in nutrients in the water is related to human presence and pasture. An undoubted expansion of human-related plants occurs since 2600 yr BP when cereals, arboreal cultivated and other synanthropic non-cultivated taxa are found. A strong reduction in arboreal vegetation occurred at 2000 yr BP, when the Roman Empire impacted a landscape undergoing climate dryness in the whole Mediterranean area. In recent centuries the human impact still remains high but spots of natural vegetation are preserved. The Lake Dojran multi-proxy analysis including pollen data provides clear evidence of the importance of this approach in paleoenvironmental reconstruction. Cross-interpretation of several proxies allows us to comprehend past vegetation dynamics and human impact in the southern Balkans.

The uranium isotope composition (234U and 238U) of detrital matter has become an essential tool for evaluating the response of erosion and catchment dynamics to climate variability on geological time scales. Relative variability of the (234U/238U) activity ratio can be used as an estimate of the time that has elapsed since physical and chemical weathering has formed grains Combined U isotopes and gas adsorption surface area analyses on two sediment samples from the Mediterranean Sea yield comminution ages up to 5 times older after sample treatment, which highlights the importance of a comprehensive removal of non-detrital matter from the bulk sediment composition. Moreover, gas sorption analysis allowed determining whether a fractal correction for calculation of the recoil fraction should be applied. Precise estimates of the recoil fraction are crucial for calculating the comminution ages, as it governs the loss of 234U from detrital matter. Samples analyzed in this study display Type II isotherms suggesting a non-porous or macroporous surface. Micro- and mesopores, which increase the surface area during gas adsorption analyses but do not contribute to the loss of 234U are absent. Thus, a fractal correction to account for micro- and mesopores is not required.

A multiproxy approach in a sediment core from Lake Trasimeno has been used to reconstruct the climate history of central Italy during the Late Pleistocene to Early Holocene period (ca. 47,000–9,000 cal yr B.P.). Ostracod assemblages and sedimentological data (lithology and carbonate content) have been used to infer past hydrological changes in the area. Ostracods were analyzed throughout the core using diversity indexes and multivariate statistic analyses (Cluster and PCA). Three main associations linked to lake level and salinity variations were recognized: 1) the C. torosa association, indicating permanent lacustrine conditions with high lake levels and low salinities; 2) the S. aculeata association, linked to very shallow/temporary waters with higher salinity conditions; and 3) the S. aculeata-E. mareotica association pointing to temporary water conditions and the highest salinities. Furthermore, the presence of C. fuscata and L. blankenbergensis during wide parts of the Late Pleistocene indicates temperatures lower than present days. Alternations of these three ostracod associations compares well with the oxygen isotope curve from Greenland (NGRIP) and are thus interpreted as climatically driven. At the Holocene transition (Termination 1), the ostracod associations indicate a delay in the increasing warming and humidity with respect to the NGRIP temperature record.

Here we present a multiproxy record (?13C, ?18O, major and minor element composition, mineralogy, and low-resolution biogenic silica content) from a lacustrine succession in the Sulmona Basin, central Italy. Based on previous tephrochronological constraints and a new 40Ar/39Ar dating of a tephra matching the widespread X-6 tephra, the record spans the ca. 129-92 ka period and documents at sub-orbital scale the climatic and environmental changes over the Last Interglacial and its transition to the Last Glacial period. The ?18O composition is interpreted as a proxy for the amount and seasonality of local precipitation, whereas variations in elemental and mineralogical composition are inferred to reflect climatic-driven changes in clastic sediment input. The observed variations are consistent among the different proxies, and indicate that periods of reduced precipitation were marked by enhanced catchment erosion, probably due to a reduction in vegetation cover. The first part of the Last Interglacial shows the most negative ?18O values. Comparison with pollen records from the Mediterranean suggests a greater seasonality of the precipitation at this time. At millennial-to-centennial time scales, comparison of the Sulmona record with speleothem ?18O records from central Italy highlights a highly coherent pattern of hydrological evolution, with enhanced variability and similar events of reduced precipitation consistently recorded by each isotope record. The observed intra-interglacial variability can potentially be linked, within the uncertainties associated with each age model, to similar variations observed in sea-surface temperature records from the Mediterranean and the North Atlantic, suggesting a link between Mediterranean hydrology and North Atlantic temperature and circulation patterns that persists during periods of low ice volume.

Mediterranean climates are characterized by strong seasonal contrasts between dry summers and wet winters. Changes in winter rainfall are critical for regional socioeconomic development, but are difficult to simulate accurately1 and reconstruct on Quaternary timescales. This is partly because regional hydroclimate records that cover multiple glacial–interglacial cycles2,3 with different orbital geometries, global ice volume and atmospheric greenhouse gas concentrations are scarce. Moreover, the underlying mechanisms of change and their persistence remain unexplored. Here we show that, over the past 1.36 million years, wet winters in the northcentral Mediterranean tend to occur with high contrasts in local, seasonal insolation and a vigorous African summer monsoon. Our proxy time series from Lake Ohrid on the Balkan Peninsula, together with a 784,000-year transient climate model hindcast, suggest that increased sea surface temperatures amplify local cyclone development and refuel North Atlantic low-pressure systems that enter the Mediterranean during phases of low continental ice volume and high concentrations of atmospheric greenhouse gases. A comparison with modern reanalysis data shows that current drivers of the amount of rainfall in the Mediterranean share some similarities to those that drive the reconstructed increases in precipitation. Our data cover multiple insolation maxima and are therefore an important benchmark for testing climate model performance.

State‐of‐the‐art paleoclimate research strongly depends on the availability of time‐equivalent markers as chronological control to disentangle interrelationships in the climate system from regional to global scale. Geomagnetic reversals are regarded as excellent age constraints because they are global events and independent from climatic conditions. However, spatial variations of timing and internal dynamics of reversals may limit their precision. Our 1.2 Ma high‐resolution (~25 cm/kyr) sediment record from Lake Ohrid is promising to precisely depict the Matuyama‐Brunhes (MB) reversal and the Jaramillo subchron. Two generations of diagenetic ferrimagnetic minerals are present in glacial intervals of the Lake Ohrid record. Early diagenetic greigite acquired a quasi synsedimentary chemical magnetization, while a late diagenetic greigite formation, triggered by the upward diffusion of H2S‐rich waters, obscures the polarity record at the top of the Jaramillo. Interglacial intervals are unaffected by greigite formation, likely due to low iron concentrations. Based on an orbitally tuned age model with tephrostratigraphic markers, the base of Jaramillo can be precisely dated to 1072.4 ka, and the MB reversal to 778.5 ka. Both polarity reversals occurred very rapidly in our record, lasting 2.3 and 1 kyr, respectively. Our results reveal that the dipole component of the Earth's magnetic field fell below the nondipole components only for a short duration in the Mediterranean region. The comparison of the timing of the MB boundary across different archives implies that the onset of the reversal provides a more synchronous age marker compared to often used midpoint ages.

Lake Ohrid, located in the Central Mediterranean region downwind of the Italian volcanoes, has great potential for developing a detailed record of the explosive activity of these volcanoes. Electron microprobe and Laser Ablation Inductively Coupled Plasma Mass Spectrometry geochemical analyses of juvenile glass fragments of previously not analysed tephra layers of the DEEP site sediment record of Lake Ohrid expand the existing tephrostratigraphy for the interval Marine Isotope Stages 1–16. The geochemical signatures of all tephra layers suggest an origin exclusively from the Italian volcanism. Eight of these tephra layers have potential equivalents in marine and terrestrial archives of the Central Mediterranean region (OH-DP-1966/SC5/A7; OH-DP-1955/CES1/A2; OH-DP-1055/S1; OH-DP-1006/S2; OH-DP-0997/S3, OH-DP-0710/S8/C-51; OH-DP-0766/ODP5/P-13; OH-DP-0505/ODP4). Nine tephra layers, which have not been described so far, help to reconstruct the late volcanic activity of Mount Vulture (OH-DP-2439) and the Paleovulsini (OH-DP-1998), the pre- and post Rio Rava activity of the Roccamonfina volcano (OH-DP-1911/-1812/-1733/-1640/-1527), the early activity of the Aeolian Arc (OH-DP-1513/-1520), and the Bracciano activity of the Monti Sabatini volcanic district (OH-DP-1175). The multi-proxy dataset and chronology of the DEEP site sediments allowed definition of the climatostratigraphic position for all tephra layers and constrain the ages of so far unknown and/or undated tephra layers. The presented data provide a crucial increase of knowledge of the Middle Pleistocene tephrostratigraphy in the Central Mediterranean back to 630 ka and allows new insights of the volcanic activity of Roccamonfina, the Roman Province, the Campanian Volcanic Zone (CVZ), the Aeolian Arc, Pantelleria, and Mount Vulture.

The widespread formation of organic rich sediments in south-east Australia during the Holocene (Marine Isotope Stage [MIS] 1) reflects the return of wetter and warmer climates following the Last Glacial Maximum (LGM). Yet, little is known about whether a similar event occurred in the region during the previous interglacial (MIS 5e). A 6.8 m sediment core (#LC2) from the now ephemeral Lake Couridjah, Greater Blue Mountains World Heritage Area, Australia, provides insight into this question. Organic rich sediments associated with both MIS 1 and 5e are identified using 14C and optically stimulated luminescence (OSL) dating techniques. Also apparent are less organic sedimentary units representing MIS 6, 5d and 2 and a large depositional hiatus. Sediment δ13C values (−34 to −26‰) suggests that C3 vegetation dominates the organic matter source through the entire sequence. The pollen record highlights the prevalence of sclerophyll trees and shrubs, with local hydrological changes driving variations in the abundance of aquatic and lake-margin species. The upper Holocene sediment (0–1.7 m) is rich in organic matter, including high concentrations of total organic carbon (TOC; 20–40%), fine charcoal and macrophyte remains. These sediments are also characterised by a large proportion of epiphytic diatoms and a substantial biogenic component (chironomids and midges). These attributes, combined with low δ13C and δ15N values, and C:N ratios of approximately 20, indicate a stable peat system in a swamp like setting, under the modern/Holocene climate. In comparison, the lower organic rich unit (MIS 5e-d) has less TOC (5–10%), is relatively higher in δ13C and δ15N, and is devoid of macrophyte remains and biogenic material. Characterisation of the organic matter pool using 13C-NMR spectroscopy identified a strong decomposition signal in the MIS 5e organic sediments relative to MIS 1. Thus the observed shifts in δ13C, δ15N and C:N data between the two periods reflects changes in the organic matter pool, driven by decompositional processes, rather than environmental conditions. Despite this, high proportions of aquatic pollen taxa and planktonic diatoms in the MIS 5e–d deposits, and their absence in the Holocene indicates that last interglacial Lake Couridjah was deeper and, or, had more permanent water, than the current one.

The bulk magnetic mineral record from Lake Ohrid, spanning the past 637 kyr, reflects large-scale shifts in hydrological conditions, and, superimposed, a strong signal of environmental conditions on glacial–interglacial and millennial timescales. A shift in the formation of early diagenetic ferrimagnetic iron sulfides to siderites is observed around 320 ka. This change is probably associated with variable availability of sulfide in the pore water. We propose that sulfate concentrations were significantly higher before ∼ 320 ka, due to either a higher sulfate flux or lower dilution of lake sulfate due to a smaller water volume. Diagenetic iron minerals appear more abundant during glacials, which are generally characterized by higher Fe / Ca ratios in the sediments. While in the lower part of the core the ferrimagnetic sulfide signal overprints the primary detrital magnetic signal, the upper part of the core is dominated by variable proportions of high- to low-coercivity iron oxides. Glacial sediments are characterized by high concentration of high-coercivity magnetic minerals (hematite, goethite), which relate to enhanced erosion of soils that had formed during preceding interglacials. Superimposed on the glacial–interglacial behavior are millennial-scale oscillations in the magnetic mineral composition that parallel variations in summer insolation. Like the processes on glacial–interglacial timescales, low summer insolation and a retreat in vegetation resulted in enhanced erosion of soil material. Our study highlights that rock-magnetic studies, in concert with geochemical and sedimentological investigations, provide a multi-level contribution to environmental reconstructions, since the magnetic properties can mirror both environmental conditions on land and intra-lake processes.

Understanding landscape evolution on geological time scales has become increasingly important in the light of recent climate warming and intensified land use. Uranium isotopes ((234U/238U) activity ratios) can be used to reconstruct catchment-wide erosion from fine-grained detrital matter, as the lighter nuclide 234U is lost from grains Loss of 234U is mainly attributed to recoil of 234Th during α-decay of 238U. However, mobilisation of 234U is also controlled by preferential oxidation and leaching of 234U from detrital grains. Further considerations are required concerning the sediment mineralogy and uranium bound to authigenic or endogenic matter. Here, we extend the discussion about the controls on previously published (234U/238U) activity ratios and uranium concentrations of detrital matter along a 5.43 m-long, Late Glacial to Holocene sedimentary record from Lake Ohrid (North Macedonia, Albania). Lake Ohrid is chosen to study how erosion responds to anthropogenic disturbances and climate variability, which are common through the Late Pleistocene and Holocene in the Mediterranean Region. We compared uranium concentration and isotope data to redox-sensitive, mineralogical and biogeochemical proxies. Mineralogical and biogeochemical data show no control on uranium concentration and (234U/238U) activity ratios. Rock magnetic redox proxies indicate uranium mobilisation from detrital matter in more oxic environments. No correlation between (234U/238U) activity ratios and rock magnetic data is observed, which implies that the redox environment has no control on the isotope signal. Monte Carlo simulations reveal that post-depositional preferential mobilisation of 234U has only negligible impact on the calculated sediment residence times. Our model implies that pre-depositional leaching can results in shorter sediment residence times but low (234U/238U) activity ratios during cold and dry intervals imply that recoil is likely the main processes explaining loss of 234U from the detrital grain. This is explained by the time scales studied herein in (>10,000 years), during which preferential leaching is seen to be not significant.

The pressing demand for sustainable antitumor drugs prompted us to investigate 3-chloropiperidines as potential mustard-based anticancer agents. In this study, an explorative set of variously decorated monofunctional 3-chloropiperidines (M-CePs) was efficiently synthesized through a fast and affordable route providing high yields of pure racemates and enantiomers. Consistently with their reactivity, M-CePs were demonstrated to alkylate DNA in vitro. On a panel of carcinoma cell lines, M-CePs exhibited low nanomolar cytotoxicity indexes, which showed their remarkable activity against pancreatic cancer cells and in all cases performed strikingly better than the chlorambucil control. Very interestingly, stereochemistry modulated the activity of M-CePs in unexpected ways, pointing to additional molecular mechanisms of action beyond the direct damage of genomic DNA. This encouraging combination of efficacy and sustainability suggests they are valid candidates for anticancer agent development.

A number of methyl-branched aldehydes impart interesting flavor impressions, and especially 12-methyltridecanal is a highly sought after flavoring compound for savory foods. Its smell is reminiscent of cooked meat and tallow. For the biotechnological production of 12-methyltridecanal, the literature was screened for fungi forming iso-fatty acids. Suitable organisms were identified and successfully grown in submerged cultures. The culture medium was optimized to increase the yields of branched fatty acids. A recombinant carboxylic acid reductase was used to reduce 12-methyltridecanoic acid to 12-methyltridecanal. The efficiency of whole-cell catalysis was compared to that of the purified enzyme preparation. After lipase-catalyzed hydrolysis of the fungal lipid extracts, the released fatty acids were converted to the corresponding aldehydes, including 12-methyltridecanal and 12-methyltetradecanal.

This brochure is designed for scientists and engineers of upcoming drilling projects and explains the key steps and important challenges in planning and executing continental scientific drilling.

In this article, we present new, high-resolution, pollen results obtained from the DEEP site sequence recovered from Lake Ohrid (Albania/FYROM) for the Last Interglacial Complex (LIC), corresponding to Marine Isotope Stage 5 (MIS 5) of the marine isotope stratigraphy. LIC covers the period between 130 and 70 ka and includes the Eemian (Last Interglacial, LI) and the succession of stadial and interstadial phases of the Early Last Glacial. During the LIC, the pollen record shows an alternation of periods characterized by forest and open vegetation, clearly resembling the well-known vegetational succession of other European records. Our results reveal three key phases for the LI: a first period (128-125 ka) with a rapid increase in temperature and precipitation, a central phase (125–118.5 ka) characterized by a slight cooling, and a late phase (118.5–112 ka), with a decline both in temperatures and precipitation. Besides the LI, we identify four more forested periods dominated by mesophilous trees and intercalated by colder and drier steppe phases, during which, however, most arboreal taxa never disappear. During the Early Last Glacial we also identify several abrupt events that can be correlated to the succession of cold events recorded in the Greenland ice core records, associated to a weakening of the North Atlantic Meridional Overturning Circulation. The new high-resolution record indicates that Lake Ohrid is an important site to understand the response of vegetation to fluctuations in regional moisture availability and temperature changes, and thus provides new evidence for the connection between the Mediterranean Region and Northern Hemisphere climate oscillations.

© 2018 Elsevier Ltd In the DEEP core from the Lake Ohrid ICDP drilling project, the carbon isotope composition of bulk organic matter (δ 13 C TOC ) over the last 516 ka shows a negative correlation with total organic carbon (TOC) and total inorganic carbon (TIC). This relationship is marked by periods of lower δ 13 C TOC values corresponding to higher TIC and TOC. Along with TOC/TN, the correlation between δ 13 C TOC and δ 13 C TIC suggests that most of the organic matter in the core is from aquatic primary production within the lake. The combination of TOC, TIC, and δ 13 C TOC is able to disentangle long-term glacial/interglacial cycles and, to a lesser extent, millennial scale climate variability. Over the longer term, δ 13 C TOC shows modest variability, indicating that the δ 13 C of the dissolved inorganic carbon (DIC) pool is stabilised by the supply of karst spring water characterised by δ 13 C DIC influenced by the bedrock δ 13 C value, and the long residence time of the lake water and well mixed upper water column promoting equilibration with atmospheric CO 2 . However, comparison between arboreal pollen (AP%), TIC and TOC data indicates that the δ 13 C TOC signal is modulated by the leaching of soil CO 2 through runoff and spring discharge, changes in primary productivity, and recycling of organic matter within the lake, all affecting δ 13 C DIC . Exceptionally low δ 13 C TOC during some interglacial periods (e.g. MIS7 and MIS9) possibly indicate rapid intensification of organic matter recycling and/or increasing stratification and enhanced methanogenesis, even if the latter process is not supported by the sedimentological data.

Soils are key to ecosystems and human societies, and their critical importance requires a better understanding of how they evolve through time. However, identifying the role of natural climate change versus human activity (e.g. agriculture) on soil evolution is difficult. Here we show that for most of the past 12,300 years soil erosion and development were impacted differently by natural climate variability, as recorded by sediments deposited in Lake Dojran (Macedonia/Greece): short-lived ( natural to anthropogenic landscape started just before, or at, the onset of the Greek ‘Dark Ages’ (~3,200 cal yr BP). This could represent the earliest recorded sign of a negative feedback between civilization and environmental impact, where the development of agriculture impacted soil resources, which in turn resulted in a slowdown of civilization expansion.

The juncture between the west–east and north–south contrasting Holocene climatic domains across the Mediterranean is complex and poorly understood. Diatom analysis of Lake Dojran (Republic of Macedonia/Greece) provides a new insight into lake levels and trophic status during the Lateglacial and Holocene periods in the northeastern Mediterranean. Following a very shallow or even desiccated state at the core base at ca. 12,500 cal yr BP, indicated by sedimentological and hydro-acoustic data, diatoms indicate lake infilling, from a shallow state with abundant benthos to a plankton-dominated relatively high lake level and eutrophic state thereafter. Diatom-inferred shallowing between ca. 12,400–12,000 cal yr BP and a very low lake level and eutrophic, oligosaline state between ca. 12,000–11,500 cal yr BP provide strong evidence for Younger Dryas aridity. The earliest Holocene (ca. 11,500–10,700 cal yr BP) was characterised by a high lake level, followed by a lake-level reduction and increased trophic level between ca. 10,700–8,500 cal yr BP. The lake was relatively deep and exhibited peak Holocene trophic level between ca. 8,500–3,000 cal yr BP, becoming shallow thereafter. The diatom data provide more robust evidence and strengthen previous lake-level interpretation based on sedimentological and geochemical data during the earliest, mid and late Holocene, and also clarify previous uncertainty in interpretation of Lateglacial and early-Holocene lake-level change. Our results are also important in disentangling regional climate effects from local catchment dynamics during the Holocene, and to this end we exploit extant regional palynological evidence for vegetation change in the highlands and lowlands. The importance of seasonality in driving Holocene climate change is assessed by reference to the summer and winter latitudinal temperature gradient (LTG) model of Davis and Brewer (2009). We suggest that increased precipitation drove the high lake level during the earliest Holocene. The early-Holocene low lake level and relatively high trophic state may result climatically from high seasonality of precipitation and locally from limited, nutrient-rich catchment runoff. We argue that the mid-Holocene relatively deep and eutrophic state was driven mainly by local vegetation succession and associated changes in catchment processes, rather than showing a close relationship to climate change. The late-Holocene shallow state may have been influenced by a temperature-induced increase in evaporative concentration, but was coupled with clear evidence for intensified human impact. This study improves understanding of Lateglacial and Holocene climate change in the northeastern Mediterranean, suggests the important role of the LTG on moisture availability during the Holocene, and clarifies the influence of catchment processes on palaeohydrology.

Lake Ohrid (Macedonia/Albania) is the oldest extant lake in Europe and exhibits an outstanding degree of endemic biodiversity. Here, we provide new high-resolution stable isotope and geochemical data from a 10 m core (Co1262) through the Late Glacial to Holocene and discuss past climate and lake hydrology (TIC, δ13Ccalcite, δ18Ocalcite) as well as the terrestrial and aquatic vegetation response to climate (TOC, TOC/N, δ13Corganic, Rock Eval pyrolysis). The data identifies 3 main zones: (1) the Late Glacial–Holocene transition represented by low TIC and TOC contents, (2) the early to mid-Holocene characterised by high TOC and increasing TOC/N and (3) the Late Holocene–Present which shows a marked decrease in TIC and TOC. In general, an overall trend of increasing δ18Ocalcite from 9 ka to present suggests progressive aridification through the Holocene, consistent with previous records from Lake Ohrid and the wider Mediterranean region. Several proxies show commensurate excursions that imply the impact of short-term climate oscillations, such as the 8.2 ka event and the Little Ice Age. This is the best-dated and highest resolution archive of past Late Glacial and Holocene climate from Lake Ohrid and confirms the overriding influence of the North Atlantic in the north-eastern Mediterranean. The data presented set the context for the International Continental scientific Drilling Program Scientific Collaboration On Past Speciation Conditions in Lake Ohrid project cores recovered in spring–summer 2013, potentially dating back into the Lower Pleistocene, and will act as a recent calibration to reconstruct climate and hydrology over the entire lake history.

Lake El'gygytgyn, located in the Far East Russian Arctic, was formed by a meteorite impact about 3.58 Ma ago. In 2009, the International Continental Scientific Drilling Program (ICDP) at Lake El'gygytgyn obtained a continuous sediment sequence of the lacustrine deposits and the upper part of the impact breccia. Here, we present grain-size data of the past 2.6 Ma. General downcore grain-size variations yield coarser sediments during warm periods and finer ones during cold periods. According to principal component analysis (PCA), the climate-dependent variations in grain-size distributions mainly occur in the coarse silt and very fine silt fraction. During interglacial periods, accumulation of coarser material in the lake center is caused by redistribution of clastic material by a wind-induced current pattern during the ice-free period. Sediment supply to the lake is triggered by the thickness of the active layer in the catchment and the availability of water as a transport medium. During glacial periods, sedimentation at Lake El'gygytgyn is hampered by the occurrence of a perennial ice cover, with sedimentation being restricted to seasonal moats and vertical conduits through the ice. Thus, the summer temperature predominantly triggers transport of coarse material into the lake center. Time series analysis that was carried out to gain insight into the frequency of the grain-size data showed variations predominately on 98.5, 40.6, and 22.9 kyr oscillations, which correspond to Milankovitch's eccentricity, obliquity and precession bands. Variations in the relative power of these three oscillation bands during the Quaternary suggest that sedimentation processes at Lake El'gygytgyn are dominated by environmental variations caused by global glacial–interglacial variations (eccentricity, obliquity), and local insolation forcing and/or latitudinal teleconnections (precession), respectively.

Seismic profiles of Far East Russian Lake El'gygytgyn which was formed by a meteorite impact some 3.6 million years ago show a stratified sediment succession that can be separated into Subunits Ia and Ib at approximately 167 m below lake floor (= ∼ 3.17 Ma). The former is well-stratified, while the latter is acoustically more massive. The sediments are intercalated with frequent mass movement deposits mainly in the proximal parts, while the distal part is almost free of such deposits at least in the upper part. In spring 2009, a long core drilled in the lake center within the framework of the International Continental Scientific Drilling Program (ICDP) penetrated the entire lacustrine sediment succession down to ~ 320 m below lake floor and about 200 m further into the meteorite-impact related bedrock. Downhole logging data down to 390 m below lake floor show that the bedrock and the lacustrine part of the core differ largely in their petrophysical characteristics. The contact between the bedrock and the lacustrine sediments is not abrupt, but rather transitional with a mixture of impact-altered bedrock clasts in a lacustrine matrix with varying percentages. Physical and chemical proxies measured on the cores can be used to divide the lacustrine part into five different clusters. These can be plotted in a redox-condition vs. input type diagram with total organic carbon content and magnetic susceptibility values indicating anoxic or oxic conditions and with the Si/Ti ratio representing more clastic or more biogenic input. Plotting the clusters in this diagram allows identifying clusters that represent glacial phases (Cluster I), super interglacials (Cluster II), and interglacial phases (Clusters III and IV).

A Late Glacial to Holocene sediment sequence (Co1260, 717 cm) from Lake Dojran, located at the boarder of the F.Y.R. of Macedonia and Greece, has been investigated to provide information on climate variability in the Balkan region. A robust age-model was established from 13 radiocarbon ages, and indicates that the base of the sequence was deposited at ca. 12 500 cal yr BP, when the lake-level was low. Variations in sedimentological (H2O, TOC, CaCO3, TS, TOC/TN, TOC/TS, grain-size, XRF, δ18Ocarb, δ13Ccarb, δ13Corg) data were linked to hydro-acoustic data and indicate that warmer and more humid climate conditions characterised the remaining period of the Younger Dryas until the beginning of the Holocene. The Holocene exhibits significant environmental variations, including the 8.2 and 4.2 ka cooling events, the Medieval Warm Period and the Little Ice Age. Human induced erosion processes in the catchment of Lake Dojran intensified after 2800 cal yr BP.

Perovskites AMO3−δ are ideal for thermochemical air separation due to their oxygen nonstoichiometry δ, which can be varied by changing the temperature and oxygen partial pressure. We show in this work how materials can be selected for chemical looping air separation from thermodynamic considerations and present thermogravimetric experiments carried out on (Ca,Sr) ferrites and manganites, and doped variants, all synthesized via a citric acid auto-combustion method. SrFe0.95Cu0.05O3−δ and Ca0.8Sr0.2MnO3−δ show the best gravimetric oxygen storage capacity of all tested materials at T < 1200 °C. The redox reactions are completed in