The Cretaceous-Paleogene boundary (similar to 66 million years ago) represents the most recent mass extinction event when an estimated 75% of all species became extinct, including all non-avian dinosaurs. Here we focus on the stable carbon isotope (delta 13C) analysis of coal and coaly sediments across the terrestrial K/Pg boundary from 10 sites, between 42 and 64 degrees N, USA and Canada. Our delta 13C data set shows a statistically significant positive correlation with paleolatitude that we interpret as a consequence of our lower latitude sites being relatively warmer and more humid than our higher latitude sites. Temporally, our data indicates that the K/Pg boundary event is represented by a unique carbon isotope shift that can be readily separated from background excursions through the latest Maastrichtian and earliest Paleogene. This excursion reaches a minimum several centimeters above the K/Pg boundary. Published geochronological constraints on our data suggest the observed carbon isotope excursion at the K/Pg boundary lasted between 10 and 36 kyr and possibly outlasted the fall-out of material injected into the atmosphere by bolide impact. Such a short duration for the K/Pg negative excursion contrasts with some marine records and in this respect may be more related to shallow marine or neritic zone responses to global sea-level and/or climatic change resulting in shorter-lived localized or regional water column deoxygenation. Notably, a short duration negative excursion at the K/Pg is compatible with events associated with the Chicxulub impact.

Alongside the mass extinction, the Cretaceous–Paleogene (K–Pg) boundary interval experienced major climate perturbations due to the Chicxulub meteorite impact and Deccan Trap volcanism. The volcanism and release of climate modifying gases likely had a drastic effect on global climate, though hypotheses of this change remain largely untested.Recent work applied the lipid biomarker palaeotemperature proxy MBT'5me to two highly chronologically constrained lignites from the Western Interior, USA (palaeolatitudes 45–51°N). This reconstruction showed that mean annual air temperatures increased by 3°C during the last ~100 ka of the Cretaceous, likely driven by Deccan volcanism and long-term release of organic carbon into the atmosphere. A transient cooling event of up to 5°C is superimposed on to the longer-term warming trend, beginning ~35 ka before the K–Pg boundary. This cooling coincided with the second (Poladpur) eruptive phase of Deccan volcanism, which correlates with the modelled climatic cooling predicted by the release of associated aerosolised SO2 emissions.To gain a more holistic understanding of the end-Cretaceous climate system, here we use the hydrogen-isotope composition of plant-wax from the same lignites to reconstruct palaeohydrology. Determining the link between volcanism-induced temperature change and hydrology prior to the Chicxulub impact will provide a framework for understanding post-impact hydrological changes.This work presents the first opportunity to evaluate palaeohydrology at a millennial scale in the Cretaceous, alongside temperature and carbon-cycling. Further, the excellent chronological constraints allow a unique insight into the relative timing of different climatic processes and major climate perturbations in the lead-up to and across the K–Pg boundary.

The rise of single-use electronics for fast health screening has prompted a reevaluation of traditional materials and manufacturing techniques to address the growing issue of electronic waste (e-waste). Inexpensive self-monitoring devices provide valuable insights into the body's essential metabolic functions. They can measure outrange values in key diseases, e.g., hyper- or hypoglycemia in diabetes. Currently, the prevalent use of nondegradable substrates and toxic metals in glycemia tests significantly contributes to plastic waste and e-waste. In this work, we propose an affordable and environmentally friendly glucose monitoring device printed on a bio-based and biocompatible substrate made of agar derived from red algae. The electrodes for the enzymatic electrochemical detection of glucose are composed of a carbon-based material, while the biorecognition element comprises of the enzyme glucose oxidase coupled with an electron mediator. The device demonstrated the electrochemical detection of physiological levels of glucose in the linear detection range of 1-15 mM, sufficient for accurately monitoring glucose level in patients' blood. In addition, this glucose sensor exhibits a low interference from other electroactive species usually present in human tissues, including blood. This all-carbon electrode sensor manufactured on our bio-sourced substrate aids the development of the next generation, metal-free, eco-friendly devices for healthcare monitoring.

Conductive, 3D, porous graphene can be produced with a CO2 laser from a large variety of materials, including wood, at room temperature, and under inert atmosphere or after treatment for fire protection. Here, we investigated the suitability for direct conversion of 46 typical European and Asian woods into laser-induced graphene (LIG), without pre-treatment. The LIG was characterized by resistance measurements to determine if a conductive layer had formed, and via Raman spectroscopy. Here, we show, for the first time, that it is possible to produce LIG on certain woods under atmospheric conditions without additional fire protection treatment. We determined that the ability to produce LIG on untreated, natural wood under ambient atmosphere is favoured overall by a high density and a diffuse-porous xylem structure, as well as a high soluble lignin content. Some of these characteristics are similar to those required for high yields in char production. Problematic for the production of LIG-based electronics is the presence of pronounced growth rings, or other geometric wood features, with density variations, which can be reduced using specific cuts with minimized growth rings and absence of rays. This is the first time that untreated wood has been directly converted into LIG using a conventional CO2 laser and ambient atmosphere. Our results represent a further step towards the development of a new generation of sustainable electronics relying on natural materials.

Alongside the Chicxulub meteorite impact, Deccan volcanism is considered a primary trigger for the Cretaceous-Paleogene (K-Pg) mass extinction. Models suggest that volcanic outgassing of carbon and sulfur-potent environmental stressors-drove global temperature change, but the relative timing, duration, and magnitude of such change remains uncertain. Here, we use the organic paleothermometer MBT'5me and the carbon-isotope composition of two K-Pg-spanning lignites from the western Unites States, to test models of volcanogenic air temperature change in the ~100 kyr before the mass extinction. Our records show long-term warming of ~3°C, probably driven by Deccan CO2 emissions, and reveal a transient (<10 kyr) ~5°C cooling event, coinciding with the peak of the Poladpur "pulse" of Deccan eruption ~30 kyr before the K-Pg boundary. This cooling was likely caused by the aerosolization of volcanogenic sulfur. Temperatures returned to pre-event values before the mass extinction, suggesting that, from the terrestrial perspective, volcanogenic climate change was not the primary cause of K-Pg extinction.

The Cretaceous-Paleogene (K-Pg) boundary marks one of the five major mass extinctions of the Phanerozoic. How the climate system responded to a bolide impact and extensive volcanism at this time over different timescales is highly debated. Here we use the distribution of branched tetraether lipids (brGDGT) from fossil peats at two sites in Saskatchewan, Canada (paleolatitude ~55°N), to generate a high-resolution (millennial) record of mean annual air temperature (MAAT) spanning the last ~4 ka of the Cretaceous and first ~30 ka of the Paleogene. Our study shows that MAATs ranged from 16–29°C, with the highest value in the first millennia of the Paleogene/ The earliest Paleogene averaged ~25°C—maintaining or enhancing warmth from the latest Cretaceous—followed by a general cooling to ~20°C over the following ~30 ka. No abrupt post-boundary cooling (e.g., an “impact winter”) or abrupt warming are evident in our data, implying that if such phenomena occurred, their duration was relatively short-lived (i.e., sub-millennial). Further, no long-term impact- or volcanism-driven warming is evident. The range of temperature change observed is considerably greater than that derived from marine proxy records over the same time interval. Our findings therefore more properly place bounds on the magnitude and duration of temperature change on land during this critical interval—the main setting for the demise of non-avian dinosaurs and the rise of mammals.

&lt;p&gt;The Cretaceous-Paleogene (K-Pg) boundary experienced major environmental perturbations due to volcanism and bolide impact, as well as the most famous mass extinction in geologic history. However, the response of the climate system to these drivers at different timescales, and thus their relationship to the mass extinction is highly debated. In particular, the role of climate change in biodiversity patterns immediately preceding the boundary is poorly understood.&amp;#160;&lt;/p&gt; &lt;p&gt;&lt;br /&gt;Lipids from fossil peats (coals) provide an opportunity to reconstruct terrestrial temperatures across the Cretaceous&amp;#8211;Paleogene boundary at a millennial-scale resolution. Here we present mean annual air temperature records spanning ~70 ka over the K-Pg boundary, from sites across North America (palaeolatitudes 45&amp;#8211;55 degrees N). Our data show that temperatures ranged from 16&amp;#8211;29 degrees C, more than 10 degrees C higher modern temperatures at equivalent latitudes in North America.&lt;/p&gt; &lt;p&gt;&lt;br /&gt;Using 5-ka temporal bins, our data show that MAATs peaked at ~26 degrees C in the last millennia of the Cretaceous, following 35 ka of warming from ~23 degrees C. Peak warmth was followed by ~5 degrees C cooling over the following 30 ka. We observe no &amp;#8220;impact winter&amp;#8221; nor a spike in temperature immediately following the boundary. If such phenomena occurred, their duration was below the resolution of our record: ~1 ka. Our record also shows a previously unrecognised brief interval of cooling from 10 to 5 ka pre-boundary.&lt;/p&gt; &lt;p&gt;&lt;br /&gt;Our study places new bounds on millennial-scale trends in MAAT change in the terrestrial realm and demonstrates large and rapid temperature swings across the K-Pg interval. These data allow for improved understanding of the role of climate in the decline of Cretaceous flora and fauna and may help elucidate the relative influence of volcanism and bolide impact on terrestrial temperatures.&lt;/p&gt;

Lipid biomarkers, such as the various bacteriohopanetetrol (BHT) isomers studied here, are useful tools in tracing bacterially mediated nitrogen and carbon cycle processes affecting greenhouse gas emissions, including the anaerobic oxidation of ammonia. Three BHT isomers occur commonly in the environment. By gas chromatog-raphy, BHT-34S elutes first; it is produced by numerous bacteria. The two later eluting isomers are more con-strained in their origin. The marine anammox bacteria 'Ca. Scalindua' is the only known producer of a BHT isomer of unknown stereochemistry (BHT -x), making BHT -x a diagnostic biomarker in anoxic marine settings. The BHT-34R isomer is produced by three freshwater aerobic heterotrophic producers (Frankia spp., Acetobacter pasteurianus, and Komagataeibacter xylinus), a freshwater serine-cycle (Type II) methanotroph (Methylocella pal-ustris), and the freshwater anammox 'Ca. Brocadia', which makes the detection of freshwater anammox using BHT-34R more complicated. We investigated whether the source of BHT-34R in freshwater environments could be ascertained via its 813C value. We used conventional on-column gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) (as opposed to high temperature GC-C-IRMS) to determine the 613C composition of acetylated BHT isomers in cultured bacteria and bacterial enrichments. We combined these with bulk biomass and substrate 613C compositions to establish carbon isotopic fractionation factors. The two anammox genera had large fractionation factors from dissolved inorganic carbon (DIC) to biomass (Delta 13Cbiomass - DIC = -43.8 to -26.4 %o) and to BHTs (Delta 13CBHT - DIC = -53.8 to -38.2 %o), which clearly distinguished them from the freshwater aerobic heterotrophic producers (Delta 13Cbiomass - substrate = -2.3 to -0.1 %o; Delta 13CBHT - substrate = -12.8 to 5.2 %o). Methylocella assimilated mainly carbon from DIC, rather than from methane, into its biomass and BHT, and previous work suggested this assimilation comes with relatively small fractionation. Thus, in peatlands, the BHT 813C values of Methylocella would not reflect the low 813C values of biogenic methane. Consequently, the presence of BHT-34R with low 813C values relates to 'Ca. Brocadia' and presents a novel tool to trace anammox in freshwater environments.

Multifunctional Biface Sensor Tag In article number 2200027, Lukas Rauter and co-workers show that the fastest-growing waste stream in the world is electronic waste. The number of sensors deployed increases rapidly, which raises the urgent demand for sustainable sensor solutions. Addressing this challenge, Silicon Austria Labs present a Multifunctional Biface Sensor Tag, enabling battery-free wireless measurements of three different sensors in a resource-efficient and flexible package.

In this article, a sustainable, multifunctional, low‐cost, wireless sensor tag is presented. The sensor tag combines three different environmental sensors in one single platform for the dedicated purpose of wireless structural health monitoring of a variety of applications. However, the adaptive design allows the integration of different sensors depending on the specific sensing task. The material consumption is minimized by double‐sided printing, resulting in compact, resource‐efficient sensor solutions. On one side, the tag is equipped with a printed antenna, a fully passive silicon‐based near‐field communication chip and a carbon‐based strain sensor, while the environmental sensors for humidity and temperature are printed on the other side. Due to its low cost, the usage of environmentally friendly materials and the absence of a battery, the biface sensor tag is a milestone in the field of wireless, sustainable electronics for ubiquitous sensing applications. The fabrication itself comprises a series of processes with a focus on efficient additive manufacturing. The characterization of the three sensors shows sensitivity values and characteristics comparable to those found in literature and industrially manufactured sensors. The utilization of a smartphone for reading out the sensor signals further emphasizes the sustainable approach of this sensor system.

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Biomedical sensing applications, including breath analysis, contribute to increasing the amount of electronic waste, as the sensors are frequently disposed, due to hygienic considerations. Consequently, the development of sustainable sensor solutions is crucial. Here, a Chitosan-based sensor proposed for the utilization in biomedical applications is presented. The sensor is fabricated on a bio-sourced and biocompatible thermoplastic polyurethane substrate, and its response to Acetone vapor is studied. The use of Chitosan, a natural biopolymer, together with additive manufacturing technologies make this sensor sustainable, while the use of biocompatible materials makes it well-suited for biomedical applications. The sensor shows a good linearity in the range between ambient Acetone concentrations of 0 -73 ppm with relative changes of 0.42% per ppm and 2.75% per ppm at ambient humidities of $50 \pm 5$%rH and $80\pm 5$%rH, respectively.

Humidity is one of the most relevant physical parameters to sense and control for a wide range of commercial and industrial applications. Consequently, there is continuing demand for the development of innovative and sustainable humidity sensor solutions. Here, the development and characterization of fully additively manufactured, highly sensitive, resistive Chitosan-based humidity sensors on flexible thermoplastic polyurethane (TPU) foil, as well as on a glass carrier substrate are presented. The sensors unite aspects of sustainability and high performance in a broad humidity range (20–90%rH). The humidity response follows an exponential curve progression with relative changes in the resistance per %rH of 6.9% and 5.7% for the glass carrier sensor and the TPU sensor, respectively. In absolute values, this means that the Chitosan-based sensors are particularly sensitive in the low humidity range with a vast dynamic range (ten times larger compared to commonly used capacitive humidity sensors). The flexible sensor on the TPU substrate shows great stability even after repeated bending. In addition, the combination of flexible and biocompatible materials (TPU and Chitosan) with additive manufacturing technologies makes the sensor particularly sustainable while having great potential for a plethora of biomedical applications.

With the recent development of LED lighting systems for plant cultivation, the use of vertical farming under controlled conditions is attracting increased attention. This study investigated the impact of a number of LED light spectra (red, blue, green and white) on the growth, development and essential oil content of lemon balm (Melissa officinalis), a herb and pharmaceutical plant species used across the world. White light and red-rich light spectra gave the best outputs in terms of impact on the growth and yield. For blue-rich spectra, the development and yield was lower despite having a significant impact on the photosynthesis activity, including Fv/Fm and NDVI values. For the blue-rich spectra, a peak wavelength of 450 mn was better than that of 435 nm. The results have practical value in terms of increased yield and the reduction of electricity consumption under controlled environmental conditions for the commercial production of lemon balm.

Within this work we demonstrate a versatile approach for the creation of laser-induced graphene sensors by a direct transfer process onto virtually any kind of substrate. The process is based on preconditioning the substrate with a layer of polyimide sealing resin and subsequently laser scribing the sensor structure onto it. By tuning the resin thickness and laser parameters, the resin is entirely removed and the resulting LIG is firmly embedded on top of the substrate. The measurement results show a gauge factor of 0.51 %.

Marine fungi exist as three major cell types: unicellular yeasts, filamentous hyphae and zoosporic early-diverging forms, such as the Chytridiomycota (chytrids). To begin to understand the ecological and biogeochemical influence of these cell types within the wider context of other plankton groups, cell size and macromolecular composition must be assessed across all three cell types. Using a mass-balance approach to culture, we describe quantitative differences in substrate uptake and subsequent macromolecular distribution in three model marine fungi: the yeast Metschnikowia zobellii, the filamentous Epicoccum nigrum and chytrid Rhizophydium littoreum. We compared these model cell types with select oleaginous phytoplankton of specific biotechnological interest through metanalysis. We hypothesise that fungal cell types will maintain a significantly different macromolecular composition to one another and further represent an alternative grazing material to bacterioplankton and phytoplankton for higher trophic levels. Assessment of carbon substrate range and utilisation using phenotype arrays suggests that marine fungi have a wide substrate range. Fungi also process organic matter to an elevated-lipid macromolecular composition with reduced-protein content. Because of their size and increased lipid composition compared to other plankton groups, we propose that fungi represent a compositionally distinct, energy-rich grazing resource in marine ecosystems. We propose that marine fungi could act as vectors of organic matter transfer across trophic boundaries, and supplement our existing understanding of the microbial loop and carbon transfer in marine ecosystems.

Latitudinal temperature gradients are a critical component of the climate system and control the transport of heat and moisture. However, this process is poorly understood during past intervals of extreme greenhouse climate, in particular owing to models suggesting that gradients must be much steeper than proxy data imply. Palaeotemperature records Late Cretaceous–Early Paleogene can provide insight into how the global climate system operates under greenhouse conditions.Much of our understanding of palaeotemperatures and gradients therein during this interval comes from marine sea-surface temperature proxy data, with very few terrestrial records. These palaeoclimate reconstructions are hampered by poor temporal resolution, difficulties in correlating between sites, and limited spatial coverage.Lipids from fossil peats across North America provide an opportunity to investigate terrestrial palaeotemperatures across the Cretaceous–Paleogene boundary and how these differ across a range of latitudes. Here we present a mean annual air temperature record spanning this interval from the Canadian High Arctic (~75°N palaeolatitude). Our data show that temperatures ranged from 0–18°C, compared with 13–27°C at contemporaneous peat-accumulating sites in Saskatchewan (~60°N palaeolatitude). These data indicate a temperature gradient of approximately 10°C. These values are similar to those modelled for the latest Cretaceous, and the latitudinal difference is comparable to the modern gradient across North America (UCAR), albeit ~20°C warmer.Our study demonstrates that although the Arctic experienced high terrestrial temperatures, the K-Pg interval saw a well-defined latitudinal temperature gradient. Further, our reconstructions fill an existing gap in the terrestrial record and highlight the value of fossil peats in palaeoclimate studies.

The Cretaceous-Paleogene (K-Pg) boundary marks one of the five major mass extinctions of the Phanerozoic. A bolide impact and flood basalt volcanism compete as triggers for the extinction, but their relative roles remain contentious. This is in part related to a paucity of robust measurements of temperature change at millennial time scales across the K-Pg boundary. Using the distribution of branched tetraether lipids in samples collected from coals (fossil peats), we present the initial findings of an ongoing study attempting to reconstruct temperatures across North America in the latest Cretaceous to earliest Paleogene. The glycerol dialkyl glycerol tetraether (brGDGTs) palaeotemperature proxy – which has been successfully applied to temperature reconstructions in the Pleistocene and Holocene – is being applied to a succession of fossil peats (lignites) that span the K-Pg boundary at ten sites from Colorado in the south to the North West Territories in the north. The Iridium anomaly that is synonymous with bolide impact at the K-Pg boundary can be used as a datum to correlate the coals. Data derived from coals deposited at a latitude of ~55 °N in Saskatchewan (Canada), are interpreted to reveal millennial-scale records of terrestrial mean annual air temperature (MAAT) for an interval spanning the latest Maastrichtian and earliest Paleogene. The MAAT record peaks at 28 °C ~1 ka (+ 4 ka/- 0.3 ka) after the K-Pg boundary, and subsequently recovers to pre-event values in the subsequent ~ 5 ka (+30 ka/-2 ka). Our unique record is consistent with an abrupt increase in atmospheric CO2 that has been widely documented at this time.

Summary This PhD project will study the lipidome of marine fungi in order to find lipid biomarkers that can help deduce the role marine fungi play in the marine biological carbon pump. This will be done by growing marine fungi under different nutrient regimes that mimic natural variations in the ocean.