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Climate warming in Antarctica involves major shifts in plant distribution and productivity. This study aims to unravel the plasticity and acclimation potential of Bryum argenteum var. muticum, a cosmopolitan moss species found in Antarctica. By comparing short-term, closed-top chamber warming experiments which mimic heatwaves, with in situ seasonal physiological rates from Cape Hallett, Northern Victoria Land, we provide insights into the general inherent resilience of this important Antarctic moss and into its adaptability to longer-term threats and stressors associated with climate change. Our findings show that B. argenteum can thermally acclimate to mitigate the effects of increased temperature under both seasonal changes and short-term pulse warming events. Following pulse warming, this species dramatically increased its carbon uptake, measured as net photosynthesis, while reductions in carbon losses, measured as dark respiration, were not observed. Rapid growth of new shoots may have confounded the effects on respiration. These results demonstrate the high physiological plasticity of this species, with acclimation occurring within only 7 days. We show that this Antarctic moss species appears to have a high level of resilience and that fast acclimation processes allow it to potentially benefit from both short-term and long-term climatic changes.

Against a changing climate, the development of evidence-based and progressive conservation policies depends on robust and quantitative baseline studies to resolve habitat natural variability and rate of change. Despite Antarctica's significant role in global climate regulation, climate trend estimates for continental Antarctica are ambiguous due to sparse long-term in situ records. Here, we present the longest, spatially explicit survey of Antarctic vegetation by harmonizing historic vegetation mapping with modern remote sensing techniques. In 1961, E. D. Rudolph established a permanent survey plot at Cape Hallett, one of the most botanically diverse areas along the Ross Sea coastline, harboring all known types of non-vascular Antarctic vegetation. Following a survey in 2004 using ground-based photography, we conducted the third survey of Rudolph's Plot in 2018 using near-ground remote sensing and methodologies closely mirroring the two historic surveys to identify long-term changes and trends. Our results revealed that the vegetation at Cape Hallett remained stable over the past six decades with no evidence of transformation related to a changing climate. Instead, the local vegetation shows strong seasonal phenology, distribution patterns that are driven by water availability, and steady perennial growth of moss. Given that East Antarctica is at the tipping point of drastic change in the near future, with biological change having been reported at certain locations, this record represents a unique and potentially the last opportunity to establish a meaningful biological sentinel that will allow us to track subtle yet impactful environmental change in terrestrial Antarctica in the 21st century.

Himantormia lugubris is an Antarctic endemic with a distribution restricted to the northwest tip of Antarctic Peninsula, adjacent islands and South Georgia Island. In this region H. lugubris is an important component of the epilithic lichen community. The species has a fruticose thallus with usually simple and flattened branches whose grey surface is often disrupted exposing the black and dominant chondroid axis. Because the photobiont cells are mainly restricted to the patchy grey areas, positive carbon balance seems to be rather difficult for this species. Therefore, the aim of this paper is to elucidate which functional strategy, possibly linked with thallus anatomy, is used by H. lugubris that enables it to be a successful species in the maritime Antarctic. To achieve this goal, we constructed a picture of the lichen’s physiological, anatomical and morphological characteristics by using a broad range of technologies, such as chlorophyll fluorescence, CO exchange and electron microscopy. We found that H. lugubris has a very low net photosynthesis, apparently restricted to the grey areas, but high respiratory rates. Therefore, positive net photosynthesis is only possible at low temperatures. Chlorophyll content is also low but is present in both gray and black areas. Our conclusion is that the only possibility for this species to achieve a positive carbon balance is to be active for long periods under optimal conditions, that means, wet, cold and with enough light, a common combination in this region of Antarctica. Given these constrains, we suggest that H. lugubris is likely to be especially sensitive species to predicted climate warming in the maritime Antarctic., Field work as well as most of the lab experiments were supported by the grant CTM2015-64728-C2-1-R (MINECO/FEDER, UE). Electron microscopy work wassupported by the grant CTM2015-64728-C2-2-R (MINECO/FEDER, UE).

Climatically extreme regions such as the polar deserts of the McMurdo Dry Valleys (78° S) in Continental Antarctica are key areas for a better understanding of changes in ecosystems. Therefore, it is particularly important to analyze and communicate current patterns of biodiversity in these sensitive areas, where precipitation mostly occurs in form of snow and liquid water is rare. Humidity provided by dew, clouds, and fog are the main water sources, especially for rock-dwelling crustose lichens as one of the most common vegetation-forming organisms. We investigated the diversity and interaction specificity of myco-/photobiont associations of 232 crustose lichen specimens, collected along an elevational gradient (171–959 m a.s.l.) within the McMurdo Dry Valleys. The mycobiont species and photobiont OTUs were identified by using three markers each (nrITS, mtSSU, RPB1, and nrITS, psbJ-L, COX2). Elevation, positively associated with water availability, turned out to be the key factor explaining most of the distribution patterns of the mycobionts. Pairwise comparisons showed Lecidea cancriformis and Rhizoplaca macleanii to be significantly more common at higher elevations and Carbonea vorticosa and Lecidea polypycnidophora at lower elevations. Lichen photobionts were dominated by the globally distributed Trebouxia OTU, Tr_A02 which occurred at all habitats. Network specialization resulting from myco-/photobiont bipartite network structure varied with elevation and associated abiotic factors. Along an elevational gradient, the spatial distribution, diversity, and genetic variability of the lichen symbionts appear to be mainly influenced by improved water relations at higher altitudes.

Primary carcinosarcoma of the spleen is a rare, aggressive splenic malignancy. To date, seven cases have been reported in the literature. We report a first case of primary carcinosarcoma of the spleen in France. A 75-year-old woman with a medical history of hysterectomy for uterine adenocarcinoma presented with left hypochondrium pain following blunt abdominal trauma. A splenic mass was noted on computed tomography (CT) scan. A splenectomy was performed by laparotomy. Histology revealed a malignant mixed Mullerian tumor. The PET scan allowed us to confirm that it was a primary lesion of the spleen. She is currently undergoing adjuvant chemotherapy despite the tumor progression. The interest of this case lies in the rarity of primary carcinosarcomas of the spleen and the circumstances of its diagnosis.

Significance Changes in the extent of ice sheets through evolutionary timescales have influenced the connectivity of soil invertebrate populations across the Antarctic landscape. We use genetic divergences to estimate isolation times for soil invertebrates along the Transantarctic Mountains. Four species of Collembola (Arthropoda) each showed genetically distinct populations at locations likely isolated for millions of years. Two further species were less genetically diverse although also range restricted. Our genetic data corroborate climate reconstructions and estimates of past warm periods of reduced ice and absent ice shelf in the Ross Sea region, during which time open seaways would have facilitated dispersal of Collembola, and possibly other taxa., During austral summer field seasons between 1999 and 2018, we sampled at 91 locations throughout southern Victoria Land and along the Transantarctic Mountains for six species of endemic microarthropods (Collembola), covering a latitudinal range from 76.0°S to 87.3°S. We assembled individual mitochondrial cytochrome c oxidase subunit 1 (COI) sequences (n = 866) and found high levels of sequence divergence at both small (600 km) spatial scales for four of the six Collembola species. We applied molecular clock estimates and assessed genetic divergences relative to the timing of past glacial cycles, including collapses of the West Antarctic Ice Sheet (WAIS). We found that genetically distinct lineages within three species have likely been isolated for at least 5.54 My to 3.52 My, while the other three species diverged more recently (

Alpha-linolenic acid (ALA, 18:3Δ9,12,15) and γ-linolenic acid \ (GLA, 18:3Δ6,9,12) are important trienoic fatty acids, which are beneficial for human health in their own right, or as precursors for the biosynthesis of long-chain polyunsaturated fatty acids. ALA and GLA in seed oil are synthesized from linoleic acid (LA, 18:2Δ9,12) by the microsomal ω-3 fatty acid desaturase (FAD3) and Δ6 desaturase (D6D), respectively. Cotton (Gossypium hirsutum L.) seed oil composition was modified by transforming with an FAD3 gene from Brassica napus and a D6D gene from Echium plantagineum, resulting in approximately 30% ALA and 20% GLA, respectively. The total oil content in transgenic seeds remained unaltered relative to parental seeds. Despite the use of a seed-specific promoter for transgene expression, low levels of GLA and increased levels of ALA were found in non-seed cotton tissues. At low temperature, the germinating cottonseeds containing the linolenic acid isomers elongated faster than the untransformed controls. ALA-producing lines also showed higher photosynthetic rates at cooler temperature and better fiber quality compared to both untransformed controls and GLA-producing lines. The oxidative stability of the novel cottonseed oils was assessed, providing guidance for potential food, pharmaceutical and industrial applications of these oils.

Poikilohydric autotrophs are the main colonizers of the permanent ice-free areas in the Antarctic tundra biome. Global climate warming and the small human footprint in this ecosystem make it especially vulnerable to abrupt changes. Elucidating the effects of climate change on the Antarctic ecosystem is challenging because it mainly comprises poikilohydric species, which are greatly influenced by microtopographic factors. In the present study, we investigated the potential effects of climate change on the metabolic activity and net primary photosynthesis (NPP) in the widespread lichen species Usnea aurantiaco-atra. Long-term monitoring of chlorophyll a fluorescence in the field was combined with photosynthetic performance measurements in laboratory experiments in order to establish the daily response patterns under biotic and abiotic factors at micro- and macro-scales. Our findings suggest that macroclimate is a poor predictor of NPP, thereby indicating that microclimate is the main driver due to the strong effects of microtopographic factors on cryptogams. Metabolic activity is also crucial for estimating the NPP, which is highly dependent on the type, distribution, and duration of the hydration sources available throughout the year. Under RCP 4.5 and RCP 8.5, metabolic activity will increase slightly compared with that at present due to the increased precipitation events predicted in MIROC5. Temperature is highlighted as the main driver for NPP projections, and thus climate warming will lead to an average increase in NPP of 167-171% at the end of the century. However, small changes in other drivers such as light and relative humidity may strongly modify the metabolic activity patterns of poikilohydric autotrophs, and thus their NPP. Species with similar physiological response ranges to the species investigated in the present study are expected to behave in a similar manner provided that liquid water is available.

The world is hungry for energy. Plant oils in the form of triacylglycerol (TAG) are one of the most reduced storage forms of carbon found in nature and hence represent an excellent source of energy. The myriad of applications for plant oils range across foods, feeds, biofuels, and chemical feedstocks as a unique substitute for petroleum derivatives. Traditionally, plant oils are sourced either from oilseeds or tissues surrounding the seed (mesocarp). Most vegetative tissues, such as leaves and stems, however, accumulate relatively low levels of TAG. Since non-seed tissues constitute the majority of the plant biomass, metabolic engineering to improve their low-intrinsic TAG-biosynthetic capacity has recently attracted significant attention as a novel, sustainable and potentially high-yielding oil production platform. While initial attempts predominantly targeted single genes, recent combinatorial metabolic engineering strategies have focused on the simultaneous optimization of oil synthesis, packaging and degradation pathways (i.e., 'push, pull, package and protect'). This holistic approach has resulted in dramatic, seed-like TAG levels in vegetative tissues. With the first proof of concept hurdle addressed, new challenges and opportunities emerge, including engineering fatty acid profile, translation into agronomic crops, extraction, and downstream processing to deliver accessible and sustainable bioenergy.

Background Patients with head and neck cancer (HNC) experience severe side effects during radiotherapy (RT). Ongoing technological advances in wearable biometric sensors allow for the collection of objective data (eg, physical activity and heart rate), which might, in the future, help detect and counter side effects before they become severe. A smartwatch such as the Apple Watch allows for objective data monitoring outside the hospital with minimal effort from the patient. To determine whether such tools can be implemented in the oncological setting, feasibility studies are needed. Objective This protocol describes the design of the OncoWatch 1.0 feasibility study that assesses the adherence of patients with HNC to an Apple Watch during RT. Methods A prospective, single-cohort trial will be conducted at the Department of Oncology, Rigshospitalet (Copenhagen, Denmark). Patients aged ≥18 years intended for primary or postoperative curatively intended RT for HNC will be recruited. Consenting patients will be asked to wear an Apple Watch on the wrist during and until 2 weeks after RT. The study will include 10 patients. Data on adherence, data acquisition, and biometric data will be collected. Demographic data, objective toxicity scores, and hospitalizations will be documented. Results The primary outcome is to determine if it is feasible for the patients to wear a smartwatch continuously (minimum 12 hours/day) during RT. Furthermore, we will explore how the heart rate and physical activity change over the treatment course. Conclusions The study will assess the feasibility of using the Apple Watch for home monitoring of patients with HNC. Our findings may provide novel insights into the patient’s activity levels and variations in heart rate during the treatment course. The knowledge obtained from this study will be essential for further investigating how biometric data can be used as part of symptom monitoring for patients with HNC. Trial Registration ClinicalTrials.gov NCT04613232; https://clinicaltrials.gov/ct2/show/NCT04613232 International Registered Report Identifier (IRRID) PRR1-10.2196/26096

There is considerable scientific interest as to how terrestrial biodiversity in Antarctica might respond, or be expected to respond, to climate change. The two species of vascular plant confined to the Antarctic Peninsula have shown clear gains in density and range extension. However, little information exists for the dominant components of the flora, lichens and bryophytes. One approach has been to look at change in biodiversity using altitude as a proxy for temperature change and previous results for Livingston Island suggested that temperature was the controlling factor. We have extended this study at the same site by using chlorophyll fluorometers to monitor activity and microclimate of the lichen, Usnea aurantiaco-atra, and the moss, Hymenoloma crispulum. We confirmed the same lapse rate in temperature but show that changes in water relations with altitude is probably the main driver. There were differences in water source with U. aurantiaco-atra benefitting from water droplet harvesting and the species performed substantially better at the summit. In contrast, activity duration, chlorophyll fluorescence and photosynthetic modelling all show desiccation to have a large negative impact on the species at the lowest site. We conclude that water relations are the main drivers of biodiversity change along the altitudinal gradient with nutrients, not measured here, as another possible contributor.

BACKGROUND Patients with head and neck cancer (HNC) experience severe side effects during radiotherapy (RT). Ongoing technological advances in wearable biometric sensors allow for the collection of objective data (eg, physical activity and heart rate), which might, in the future, help detect and counter side effects before they become severe. A smartwatch such as the Apple Watch allows for objective data monitoring outside the hospital with minimal effort from the patient. To determine whether such tools can be implemented in the oncological setting, feasibility studies are needed. OBJECTIVE This protocol describes the design of the OncoWatch 1.0 feasibility study that assesses the adherence of patients with HNC to an Apple Watch during RT. METHODS A prospective, single-cohort trial will be conducted at the Department of Oncology, Rigshospitalet (Copenhagen, Denmark). Patients aged ≥18 years intended for primary or postoperative curatively intended RT for HNC will be recruited. Consenting patients will be asked to wear an Apple Watch on the wrist during and until 2 weeks after RT. The study will include 10 patients. Data on adherence, data acquisition, and biometric data will be collected. Demographic data, objective toxicity scores, and hospitalizations will be documented. RESULTS The primary outcome is to determine if it is feasible for the patients to wear a smartwatch continuously (minimum 12 hours/day) during RT. Furthermore, we will explore how the heart rate and physical activity change over the treatment course. CONCLUSIONS The study will assess the feasibility of using the Apple Watch for home monitoring of patients with HNC. Our findings may provide novel insights into the patient’s activity levels and variations in heart rate during the treatment course. The knowledge obtained from this study will be essential for further investigating how biometric data can be used as part of symptom monitoring for patients with HNC. CLINICALTRIAL ClinicalTrials.gov NCT04613232; https://clinicaltrials.gov/ct2/show/NCT04613232 INTERNATIONAL REGISTERED REPORT PRR1-10.2196/26096

Plant seeds have long been promoted as a production platform for novel fatty acids such as the ω3 long-chain (≥ C20) polyunsaturated fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) commonly found in fish oil. In this article we describe the creation of a canola (Brassica napus) variety producing fish oil-like levels of DHA in the seed. This was achieved by the introduction of a microalgal/yeast transgenic pathway of seven consecutive enzymatic steps which converted the native substrate oleic acid to α-linolenic acid and, subsequently, to EPA, docosapentaenoic acid (DPA) and DHA. This paper describes construct design and evaluation, plant transformation, event selection, field testing in a wide range of environments, and oil profile stability of the transgenic seed. The stable, high-performing event NS-B50027-4 produced fish oil-like levels of DHA (9–11%) in open field trials of T3 to T7 generation plants in several locations in Australia and Canada. This study also describes the highest seed DHA levels reported thus far and is one of the first examples of a deregulated genetically modified crop with clear health benefits to the consumer.

Abiotic factors are major determinants of soil animal distributions and their dominant role is pronounced in extreme ecosystems, with biotic interactions seemingly playing a minor role. We modelled co-occurrence and distribution of the three nematode species that dominate the soil food web of the McMurdo Dry Valleys (Antarctica). Abiotic factors, other biotic groups, and autocorrelation all contributed to structuring nematode species distributions. However, after removing their effects, we found that the presence of the most abundant nematode species greatly, and negatively, affected the probability of detecting one of the other two species. We observed similar patterns in relative abundances for two out of three pairs of species. Harsh abiotic conditions alone are insufficient to explain contemporary nematode distributions whereas the role of negative biotic interactions has been largely underestimated in soil. The future challenge is to understand how the effects of global change on biotic interactions will alter species coexistence., Tancredi Caruso et al. analyze biodiversity survey data from the McMurdo Dry Valleys, an extreme desert ecosystem in Antarctica in which abiotic factors are thought to determine species distributions. Focusing on three nematode species, they find that abiotic factors alone cannot explain the data and interaction between species have been historically underestimated.

Oliver D Tupper,1 Thorbjørn L Gregersen,1 Thomas Ringbaek,1,2 Eva Brøndum,1 Ejvind Frausing,1 Allan Green,1 Charlotte S Ulrik1,2 1Department of Pulmonary Medicine, Hvidovre Hospital, Hvidovre, Denmark; 2Institute of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark Background and objective: Telemonitoring (TM) of patients with COPD has gained much interest, but studies have produced conflicting results. We aimed to investigate the effect of TM with the option of video consultations on quality of life (QoL) in patients with severe COPD. Patients and methods: COPD patients at high risk of exacerbations were eligible for the 6-month study and a total of 281 patients were equally randomized to either TM (n=141) or usual care (n=140). TM comprised recording of symptoms, oxygen saturation, spirometry, and video consultations. Algorithms generated alerts if readings breached thresholds. Both groups filled in a health-related QoL questionnaire (15D©) and the COPD Assessment Test (CAT) at baseline and at 6 months. Within-group differences were analyzed by paired t-test. Results: Most of the enrolled patients had severe COPD (86% with Global Initiative for Chronic Obstructive Lung Disease stage 3 or 4 and 45% with admission for COPD within the last year, respectively). No difference in drop-out rate and mortality was found between the groups, and likewise there was no difference in 15D or CAT at baseline. At 6 months, a significant improvement of 0.016 in 15D score (p=0.03; minimal clinically important difference 0.015) was observed in the TM group (compared to baseline), while there was no improvement in the control group -0.003 (p=0.68). After stratifying 15D score at baseline to

Lichens are one of the common dominant biota in biological soil crusts (biocrusts), a community that is one of the largest in extent in the world. Here we present a summary of the main features of the lifestyle of soil crust lichens, emphasizing their habitat, ecophysiology and versatility. The soil crust is exposed to full light, often to high temperatures and has an additional water source, the soil beneath the lichens. However, despite the open nature of the habitat the lichens are active under shady and cooler conditions and avoid climate extremes of high temperature and light. In temperate and alpine habitats they can also be active for long periods, several months in some cases. They show a mixture of physiological constancy (e.g. similar activity periods and net photosynthetic rates) but also adaptations to the habitat (e.g. the response of net photosynthesis to thallus water content can differ for the same lichen species in Europe and the USA and some species show extensive rhizomorph development). Despite recent increased research, aspects of soil crust ecology, for example under snow, remain little understood.

Summary Vegetable oils extracted from oilseeds are an important component of foods, but are also used in a range of high value oleochemical applications. Despite being biodegradable, nontoxic and renewable current plant oils suffer from the presence of residual polyunsaturated fatty acids that are prone to free radical formation that limit their oxidative stability, and consequently shelf life and functionality. Many decades of plant breeding have been successful in raising the oleic content to ~90%, but have come at the expense of overall field performance, including poor yields. Here, we engineer superhigh oleic (SHO) safflower producing a seed oil with 93% oleic generated from seed produced in multisite field trials spanning five generations. SHO safflower oil is the result of seed‐specific hairpin‐based RNA interference of two safflower lipid biosynthetic genes, FAD2.2 and FATB, producing seed oil containing less than 1.5% polyunsaturates and only 4% saturates but with no impact on lipid profiles of leaves and roots. Transgenic SHO events were compared to non‐GM safflower in multisite trial plots with a wide range of growing season conditions, which showed no evidence of impact on seed yield. The oxidative stability of the field‐grown SHO oil produced from various sites was 50 h at 110°C compared to 13 h for conventional ~80% oleic safflower oils. SHO safflower produces a uniquely stable vegetable oil across different field conditions that can provide the scale of production that is required for meeting the global demands for high stability oils in food and the oleochemical industry.

Within Antarctica there are large gradients both in climate and in vegetation which offer opportunities to investigate links between the two. The activity (% total time active) of lichens and bryophytes in hydric and xeric environments was monitored at Livingston Island (62°39'S). This adds a northern site with a maritime, cloudy climate to previous studies in the southern Antarctic Peninsula and the Dry Valleys (78°S). Annual activity increases northwards from less than 1% to nearly 100%. There is a major and consistent difference between hydric sites which, with snow melt, can be 100% active in summer months even in the Dry Valleys, and xeric sites which, depending on precipitation, rarely exceed 80% activity even at Livingston Island. Mosses dominate hydric sites and lichens the xeric sites all along the gradient. Mean temperatures when active are 2–4°C at all sites, as liquid water is required. Light is a potential major stress reaching 880 µmol m-2s-1when active in continental sites. The lack of extremes in temperatures and light combined with high activity levels means that summer at Livingston Island is one of the better sites for lichen and bryophyte growth in the world.

Lichens have been used as biomonitors for multiple purposes. They are well-known as air pollution indicators around urban and industrial centers. More recently, several attempts have been made to use lichens as monitors of climate change especially in alpine and polar regions. In this paper, we review the value of saxicolous lichens for monitoring environmental changes in Antarctic regions. The pristine Antarctica offers a unique opportunity to study the effects of climate change along a latitudinal gradient that extends between 62° and 87° S. Both lichen species diversity and thallus growth rate seem to show significant correlations to mean annual temperature for gradients across the continent as well as to short time climate oscillation in the Antarctic Peninsula. Competition interactions appear to be small so that individual thalli develop in balance with environmental conditions and, as a result, can indicate the trends in productivity for discrete time intervals over long periods of time.

Summary Palmitic acid (C16:0) already makes up approximately 25% of the total fatty acids in the conventional cotton seed oil. However, further enhancements in palmitic acid content at the expense of the predominant unsaturated fatty acids would provide increased oxidative stability of cotton seed oil and also impart the high melting point required for making margarine, shortening and confectionary products free of trans fatty acids. Seed‐specific RNAi‐mediated down‐regulation of β‐ketoacyl‐ACP synthase II (KASII) catalysing the elongation of palmitoyl‐ACP to stearoyl‐ACP has succeeded in dramatically increasing the C16 fatty acid content of cotton seed oil to well beyond its natural limits, reaching up to 65% of total fatty acids. The elevated C16 levels were comprised of predominantly palmitic acid (C16:0, 51%) and to a lesser extent palmitoleic acid (C16:1, 11%) and hexadecadienoic acid (C16:2, 3%), and were stably inherited. Despite of the dramatic alteration of fatty acid composition and a slight yet significant reduction in oil content in these high‐palmitic (HP) lines, seed germination remained unaffected. Regiochemical analysis of triacylglycerols (TAG) showed that the increased levels of palmitic acid mainly occurred at the outer positions, while C16:1 and C16:2 were predominantly found in the sn‐2 position in both TAG and phosphatidylcholine. Crossing the HP line with previously created high‐oleic (HO) and high‐stearic (HS) genotypes demonstrated that HP and HO traits could be achieved simultaneously; however, elevation of stearic acid was hindered in the presence of high level of palmitic acid.

In the McMurdo Dry Valleys, located in Southern Victoria Land, Antarctica, endolithic communities are important photoautotrophic primary producers. Being poikilohydric organisms their active time and carbon fixation rates rely on local water availability. In Antarctica the parallel variation in the severity of the thermal and hydric environment makes simple transect and gradient based modelling complicated. Here we interpret samples collected over several seasons in terms of rock type (sandstone, marble and granite) and location (distance from sea, altitude) on the colonization, species composition, chlorophyll content, biomass as well as stable carbon isotopic composition and 14 C age of the endolithic communities. Distance from coast was highly correlated with altitude of the sampling locations and this complicated disentangling of climatic drivers. Nevertheless, stable carbon isotopic composition allowed insight into hydration regime and 14C radiocarbon age into productivity. Endolithic communities in sandstone at high altitude sites have higher biomass but are less often active than communities in lowland granite.

Biological soil crusts (BSCs) are small-scale communities of lichens, mosses, algae, and cyanobacteria that cover much of the surface area in regions where vascular plant growth is restricted due to harsh environmental conditions, such as perpetually ice-free areas in terrestrial Antarctic environments and alpine areas above the tree line. To our knowledge, none of the available studies provides a direct Antarctic-alpine comparison of BSC activity periods and the water use, both key traits to understand their physiological behavior and therefore related growth and fitness. Here, activity patterns and water relations were studied at two sites, one in continental Antarctica (Garwood Valley 78°S) and one in the High Alps of Austria (Hochtor, Großglockner 2350m). BSCs in continental Antarctica were only rarely active, and if so, then during melt after snowfalls and by fog. In the Austrian Alps, BSCs were continuously active and additionally activated by rainfall, fog, and dew. Consequently, high alpine BSCs can be expected to have much higher photosynthetic productivity supporting higher growth rates than the same functional vegetation unit has in continental Antarctica.

In extreme conditions ketosis can progress to ketoacidosis, a dangerous and potentially life-threatening condition. Ketoacidosis is most common in new or poorly treated type 1 diabetes. The acidosis is usually attributed to the ‘acidic’ nature of the ketone bodies (acetoacetate, 3-hydroxybutyrate, and acetone). However, acetoacetate and 3-hydroxybutyrate are produced not as acids but as their conjugate bases, and acetone is neither an acid nor a base. This raises the question of why severe ketosis is accompanied by acidosis. Here, we analyze steps in ketogenesis and identify four potential sources: adipocyte lipolysis, hydrolysis of inorganic pyrophosphate generated during synthesis of fatty acyl-coenzyme A (CoA), the reaction catalyzed by an enzyme in the β-oxidation pathway (3-hydroxyacyl-CoA dehydrogenase), and increased synthesis of CoA.

Chronosequences at the forefront of retreating glaciers provide information about colonization rates of bare surfaces. In the northern hemisphere, forest development can take centuries, with rates often limited by low nutrient availability. By contrast, in front of the retreating Pia Glacier (Tierra del Fuego, Chile), a Nothofagus forest is in place after only 34 yr of development, while total soil nitrogen (N) increased from near zero to 1.5%, suggesting a strong input of this nutrient. We measured N-fixation rates, carbon fluxes, leaf N and phosphorus contents and leaf δ15 N in the dominant plants, including the herb Gunnera magellanica, which is endosymbiotically associated with a cyanobacterium, in order to investigate the role of N-fixing and mycorrhizal symbionts in N-budgets during successional transition. G. magellanica presented some of the highest nitrogenase activities yet reported (potential maximal contribution of 300 kg N ha-1 yr-1 ). Foliar δ15 N results support the framework of a highly efficient N-uptake and transfer system based on mycorrhizas, with c. 80% of N taken up by the mycorrhizas potentially transferred to the host plant. Our results suggest the symbiosis of G. magellanica with cyanobacteria, and trees and shrubs with mycorrhizas, to be the key processes driving this rapid succession.

The factors that control lichen distribution in Antarctica are still not well understood, and in this investigation we focused on the distribution, local and continental, and gas exchange of a species pair, closely related lichens with differing reproductive strategies, Usnea aurantiaco-atra (fertile) and Usnea antarctica (sterile, sorediate). The local distributions of these species were recorded along an altitudinal gradient of nearly 300 m at South Bay, Livingston Island, and microclimate was also recorded over 1 year. The photosynthetic responses to temperature, light and thallus water content were determined under controlled conditions in the laboratory. The species were almost identical in their photosynthetic profiles. Locally, on Livingston Island, U. antarctica was confined to low altitude sites which were warmer and drier, whilst U. aurantiaco-atra was present at all altitudes. This contrasts with its distribution across Antarctica where U. antarctica grows 9° latitude further south than U. aurantiaco-atra. Temperature appears not to be the main controller of distribution in these species, but dryness of habitat, which will influence length of activity periods, may be important.

Cape Hallett (72°19′S; 170°13′E) lies at the northern end of the western coastline of the Ross Sea region, and, to date, there appears to be no full description of its terrestrial flora despite its probable importance in understanding links between biodiversity and latitude. Here we present information about lichens and mosses from published papers, herbarium collections and personal surveys for Cape Hallett and seven nearby sites. A total of 59 lichen and 11 moss species are reported for these eight sites. Cape Hallett is one of the richest sites for terrestrial biodiversity in the Ross Sea region with about 46 lichen species and nine species of bryophytes. Lichens have their greatest diversity on the upper scree and summit area (30 species, 330 m), the least within the large penguin colony at sea level (one species). The station at Cape Hallett was established in 1957, and some of the earliest ecological and ecophysiological studies in Antarctica were carried out there. Historical comparisons are possible and have revealed considerable changes in vegetation in the lower flush area, a high level of frost heave disturbance, new lichen growth rate estimates for northern Victoria Land and extreme stability of the snow banks on the scree slopes. Cape Hallett represents a very important site for studies on links between terrestrial flora and the environment as well as on possible effects of climate change.

Simultaneous gene silencing of both FAD2 genes in high linoleic acid flax leads to high level of oleic acid, which is stable across multiple generations. High oleic oil is one of the preferred traits in oil crop engineering due to its stability and multiple applications as an industrial feedstock. Flax possesses two isoforms of FAD2 enzymes that desaturate monounsaturated oleic acid to polyunsaturated linoleic acid. These two enzymes are encoded by two FAD2 genes. By simultaneous gene silencing both FAD2 genes in high linoleic acid flax, Linola, high level of oleic acid up to 80 % was achieved in 69 silencing lines. The high oleic trait was stable across multiple generations with oleic acid reaching up to 77 % in homozygote T3 progeny. The RNAi-mediated gene-silencing approach generated high oleic linseed oil, as well as a high oleic platform that can be exploited for further fatty acid engineering.