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Selective catalytic oxidation of glucose to glucaric acid is still challenging due to the potential formation of a large range of by‐products. ZrO2 supported AuPt catalysts are very efficient for this reaction under base‐free conditions, in aqueous phase. Different preparation methods were tested and the catalysts synthesized by co‐impregnation using NaBH4 as reductant gave the most promising results. We demonstrated that the presence of a pure AuPt alloy is critical for the selective formation of glucaric acid. We have shown that when ultrasonication was used during preparation, less by‐products were formed, increasing significantly final yield of glucaric acid, up to 71 %. The Au/Pt ratio affects the catalytic results and an optimal ratio around 1.1 was determined. Finally, the catalyst is stable up to 196 h in continuous reactor. [ABSTRACT FROM AUTHOR]

Outdoor recreation is an essential way many people engage with nature. The provision of public spaces for recreation intersects with conservation practices motivated by intertwined social and ecological values, such as strict practices associated with the concept of 'wilderness'. Debates persist about how such concepts and management practices influence people's recreation experiences.Many US public land management agencies facilitate opportunities for outdoor recreation, relying on management frameworks and tools intended to foster specific experiential qualities. But these frameworks and tools assume simplistic relationships between settings and people's experiences, and managers rarely assess these relationships.This study uses a data set of nearly 70,000 crowdsourced trip reports from a hiking website to understand the qualities of visitors' experiences on trails. We study the geographic distribution of experiential qualities commonly associated with US wilderness areas: aesthetics, awe, challenge, pristineness, quietness, solitude and timelessness. Using analytical methods that rely on machine learning and natural language processing, we identify these experiential qualities in trip reports from hundreds of routes, and use generalized linear models to analyse relationships between the frequency of each experiential quality and the route's administrative, built, biophysical, geographic and social settings.We find that four of the seven experiential qualities (aesthetics, awe, challenge and solitude) are commonly described in trip reports, each appearing in 15%–55% of manually coded reports. The extent to which setting characteristics explained variability in experiences differed, ranging from 34% of the variability in the proportion of trip reports describing aesthetics to 55% for awe. The setting characteristics associated with each experiential quality also differed, with characteristics such as trail mileage and summit destinations having stronger influences on experiential qualities than characteristics such as wilderness designation.Synthesis and applications. Our findings suggest the need to consider more diverse variables in experience–setting relationships, develop more robust models to characterize those relationships and create new data sources to represent understudied variables. These advances would help empirically inform and improve frameworks and tools used for recreation and wilderness planning and monitoring, and potentially promote more responsive management to evolving social–ecological values. Read the free Plain Language Summary for this article on the Journal blog. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Redesigning agrosystems to include more ecological regulations can help feed a growing human population, preserve soils for future productivity, limit dependency on synthetic fertilizers, and reduce agriculture contribution to global changes such as eutrophication and warming. However, guidelines for redesigning cropping systems from natural systems to make them more sustainable remain limited. Synthetizing the knowledge on biogeochemical cycles in natural ecosystems, we outline four ecological systems that synchronize the supply of soluble nutrients by soil biota with the fluctuating nutrient demand of plants. This synchrony limits deficiencies and excesses of soluble nutrients, which usually penalize both production and regulating services of agrosystems such as nutrient retention and soil carbon storage. In the ecological systems outlined, synchrony emerges from plant–soil and plant–plant interactions, eco‐physiological processes, soil physicochemical processes, and the dynamics of various nutrient reservoirs, including soil organic matter, soil minerals, atmosphere, and a common market. We discuss the relative importance of these ecological systems in regulating nutrient cycles depending on the pedoclimatic context and on the functional diversity of plants and microbes. We offer ideas about how these systems could be stimulated within agrosystems to improve their sustainability. A review of the latest advances in agronomy shows that some of the practices suggested to promote synchrony (e.g., reduced tillage, rotation with perennial plant cover, crop diversification) have already been tested and shown to be effective in reducing nutrient losses, fertilizer use, and N2O emissions and/or improving biomass production and soil carbon storage. Our framework also highlights new management strategies and defines the conditions for the success of these nature‐based practices allowing for site‐specific modifications. This new synthetized knowledge should help practitioners to improve the long‐term productivity of agrosystems while reducing the negative impact of agriculture on the environment and the climate. [ABSTRACT FROM AUTHOR]

The evolution of the first plant‐based terrestrial ecosystems in the early Palaeozoic had a profound effect on the development of soils, the architecture of sedimentary systems, and shifts in global biogeochemical cycles. In part, this was due to the evolution of complex below‐ground (root‐like) anchorage systems in plants, which expanded and promoted plant–mineral interactions, weathering, and resulting surface sediment stabilisation. However, little is understood about how these micro‐scale processes occurred, because of a lack of in situ plant fossils in sedimentary rocks/palaeosols that exhibit these interactions. Some modern plants (e.g., liverworts, mosses, lycophytes) share key features with the earliest land plants; these include uni‐ or multicellular rhizoid‐like anchorage systems or simple roots, and the ability to develop below‐ground networks through prostrate axes, and intimate associations with fungi, making them suitable analogues. Here, we investigated cryptogamic ground covers in Iceland and New Zealand to better understand these interactions, and how they initiate the sediment stabilisation process. We employed multi‐dimensional and multi‐scale imaging, including scanning electron microscopy (SEM) and X‐ray Computed Tomography (μCT) of non‐vascular liverworts (Haplomitriopsida and complex thalloids) and mosses, with additional imaging of vascular lycopods. We find that plants interact with their substrate in multiple ways, including: (1) through the development of extensive surface coverings as mats; (2) entrapment of sediment grains within and between networks of rhizoids; (3) grain entwining and adherence by rhizoids, through mucilage secretions, biofilm‐like envelopment of thalli on surface grains; and (4) through grain entrapment within upright 'leafy' structures. Significantly, μCT imaging allows us to ascertain that rhizoids are the main method for entrapment and stabilisation of soil grains in the thalloid liverworts. This information provides us with details of how the earliest land plants may have significantly influenced early Palaeozoic sedimentary system architectures, promoted in situ weathering and proto‐soil development, and how these interactions diversified over time with the evolution of new plant organ systems. Further, this study highlights the importance of cryptogamic organisms in the early stages of sediment stabilisation and soil formation today. [ABSTRACT FROM AUTHOR]

Aim: To investigate sleep apnoea prevalence, factors influencing severity, and associations between sleep apnoea severity and micro‐/macrovascular complications in a large population of patients with type 1 diabetes. Materials and methods: This French multicentre prospective cohort study was conducted between July 2016 and June 2020. Adults with type 1 diabetes using an insulin pump were eligible. Home care provider nurses collected demographic and clinical data and set up oximetry to determine the oxygen desaturation index (ODI). No, mild–moderate and severe sleep apnoea were defined as ODI <15 events/h, 15 to <30 events/h and ≥30 events/h, respectively. Univariate and multivariate analyses were performed to identify factors associated with sleep apnoea, and associations between sleep apnoea severity and micro‐/macrovascular complications were determined using logistic regression. Results: Of 769 participants, 12.4% and 3.4% had mild‐to‐moderate or severe sleep apnoea, respectively. Factors significantly associated with sleep apnoea on multivariate analysis were age, sex, body mass index (BMI) and hypertension. After adjustment for age, sex and BMI, presence of severe sleep apnoea was significantly associated with macrovascular complications (odds ratio vs. no sleep apnoea: 3.96 [95% confidence interval 1.43‐11.11]; P < 0.01), while mild‐to‐moderate sleep apnoea was significantly associated with presence of diabetic retinopathy (odds ratio 2.09 [95% confidence interval 1.10‐3.74]; P < 0.01). Conclusion: Sleep apnoea is a significant comorbidity in patients with type 1 diabetes, especially with respect to diabetic complications. This highlights the need for sleep apnoea screening and management in these individuals. [ABSTRACT FROM AUTHOR]

The priming effect (PE) is a key mechanism contributing to the carbon balance of the soil ecosystem. Almost 100 years of research since its discovery in 1926 have led to a rich body of scientific publications to identify the drivers and mechanisms involved. A few review articles have summarised the acquired knowledge; the last major one was published in 2010. Since then, knowledge on the soil microbial communities involved in PE and in PE + C sequestration mechanisms has been considerably renewed.This article reviews current knowledge on soil PE to state to what extent new insights may improve our ability to understand and predict the evolution of soil C stocks. We propose a framework to unify the different concepts and terms that have emerged from the international scientific community on this topic, report recent discoveries and identify key research needs.Seventy per cent of the studies on the soil PE were published in the last 10 years, illustrating a renewed interest for PE, probably linked to the increased concern about the importance of soil carbon for climate change and food security issues. Among all the drivers and mechanisms proposed along with the different studies to explain PE, some are named differently but actually refer to the same object. This overall introduces 'artificial' complexity for the mechanistic understanding of PE, and we propose a common, shared terminology. Despite the remaining knowledge gaps, consistent progress has been achieved to decipher the abiotic mechanisms underlying PE, together with the role of enzymes and the identity of the microbial actors involved. However, including PE into mechanistic models of SOM dynamics remains challenging as long as the mechanisms are not fully understood. In the meantime, empirical alternatives are available that reproduce observations accurately when calibration is robust.Based on the current state of knowledge, we propose different scenarios depicting to what extent PE may impact ecosystem services under climate change conditions. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Heavy metal concentrations often vary at small spatial scales not captured by air monitoring networks, with implications for environmental justice in industrial‐adjacent communities. Pollutants measured in moss tissues are commonly used as a screening tool to guide use of more expensive resources, like air monitors. Such studies, however, rarely address environmental justice issues or involve the residents and other decision makers expected to utilize results. Here, we piloted a community science approach, engaging over 55 people from nine institutions, to map heavy metals using moss in two industrial‐adjacent neighborhoods. This area, long known for disproportionately poor air quality, health outcomes, and racial inequities, has only one monitor for heavy metals. Thus, an initial understanding of spatial patterns is critical for gauging whether, where, and how to invest further resources toward investigating heavy metals. Local youth‐led sampling of the moss Orthotrichum lyellii from trees across a 250 × 250 m sampling grid (n = 79) and generated data comparable to expert‐collected samples (n = 19). We mapped 21 chemical elements measured in moss, including 6 toxic "priority" metals: arsenic, cadmium, chromium, cobalt, lead, and nickel. Compared to other urban O. lyellii studies, local moss had substantially higher priority metals, especially arsenic and chromium, encouraging community members to investigate further. Potential hotspots of priority metals varied somewhat but tended to peak near the central industrial core where many possible emission sources, including legacy contamination and converge. Informed by these findings, community members successfully advocated regulators for a second study phase—a community‐directed air monitoring campaign to evaluate residents' exposure to heavy metals—as is needed to connect moss results back to the partnership's core goal of understanding drivers of health disparities. This follow‐up campaign will measure metals in the PM10 fraction owing to clues in the current study that airborne soil and dust may be locally important carriers of priority metals. Future work will address how our approach combining bioindicators and community science ultimately affects success addressing longstanding environmental justice concerns. For now, we illustrate the potential to co‐create new knowledge, to help catalyze and strategize next steps, in a complex air quality investigation. [ABSTRACT FROM AUTHOR]

The taxonomy of the extant dinoflagellate genus Gonyaulax is challenging since its thecate morphology is rather conservative. In contrast, cysts of Gonyaulax are varied in morphology and have been related with the fossil‐based genera Spiniferites and Impagidinium. To better understand the systematics of Gonyaulax species, we performed germination experiments on cysts that can be identified as S. ristingensis, an unidentified Spiniferites with petaloid processes here described as Spiniferites pseudodelicatus sp. nov. and Impagidinium variaseptum from Chinese and Portuguese waters. Despite marked differences in cyst morphology, motile cells of S. pseudodelicatus and I. variaseptum are indistinguishable from Gonyaulax baltica. Motile cells hatched from S. ristingensis are morphologically similar to G. baltica as well but differ in the presence of one pronounced antapical spine. Three new species, Gonyaulax amoyensis (cyst equivalent S. pseudodelicatus), Gonyaulax bohaiensis (cyst equivalent I. variaseptum), and Gonyaulax portimonensis (cyst equivalent S. ristingensis), were erected. In addition, a new ribotype (B) of G. baltica was reported from South Korea and a bloom of G. baltica ribotype B is reported from New Zealand. Molecular phylogeny based on LSU and SSU rRNA gene sequences revealed that Gonyaulax species with minute or short antapical spines formed a well‐resolved clade, whereas species with two pronounced antapical spines or lack of antapical spines formed the sister clade. Six strains of four above species were examined for yessotoxin production by liquid chromatography coupled with tandem mass spectrometry, and very low concentrations of yessotoxin were detected for one G. bohaiensis strain. [ABSTRACT FROM AUTHOR]

Bark beetles, fossil wood, Upper Cretaceous, wood-colonizing fungi, Araucariaceae, Ascomycota Here we describe a fungus colonizing wood of the extinct conifer I Agathoxylon i Hartig from the Upper Cretaceous Mzamba Formation of Pondoland (South Africa), and we draw comparisons with a blue stain fungus colonizing the wood of extant I Pinus strobus i . Keywords: Araucariaceae; Ascomycota; bark beetles; fossil wood; Upper Cretaceous; wood-colonizing fungi EN Araucariaceae Ascomycota bark beetles fossil wood Upper Cretaceous wood-colonizing fungi 1032 1037 6 01/10/22 20220201 NES 220201 Introduction Fossil fungi are frequently observed in association with fossil plants in a geological record that dates back over 400 Myr to the beginning of the Devonian Period (e.g. Strullu-Derrien I et al i ., 2014, 2018; Taylor I et al i ., 2015; Krings I et al i ., 2018; Krings & Harper, 2019). In most modern trees, two types of wood can be recognized: sapwood is the outer, pale-coloured wood, and heartwood the inner, mostly darker wood (Githiomi & Dougal, 2012). [Extracted from the article]

Palaeontology relies on the description of fossil morphologies to understand the evolutionary history of life on Earth. Yet much remains unknown about the impact of fossilization processes, even though these may introduce biases into palaeobiological interpretations. Here, we report the characterization of fossilized remains of the earliest known woody plant Armoricaphyton chateaupannense preserved either in 2D (as flat carbonaceous films) or in 3D (as organo‐mineral structures) in early Devonian shales (c. 407 Ma) of the Armorican Massif on the northern margin of Gondwana. To document the fine‐scale structure and the chemistry of the tracheids of this ancient plant, we used propagation phase contrast synchrotron radiation X‐ray microcomputed tomography (PPC‐SRμCT), transmission electron microscopy (TEM) and synchrotron‐based scanning transmission X‐ray microscopy (STXM) coupled with X‐ray absorption near edge structure (XANES) spectroscopy. PPC‐SRμCT enables digital visualization of cell walls in unprecedented detail for the specimens preserved in 3D revealing structures similar to those observed in extant lignified cells, thereby strongly suggesting that the earliest woody plant A. chateaupannense originally contained lignin compounds. STXM‐based XANES and TEM data show that, whatever the preservation modes (3D vs 2D), the remaining organic matter has a chemical composition rather typical of pyrobitumen compounds, raising the possibility of an original source other than lignin. The pyrobitumen compounds also contains automorphic Ti‐nanominerals interpreted as a diagenetic feature. Altogether, the present study illustrates that anatomical and chemical preservations may not always be correlated. [ABSTRACT FROM AUTHOR]

Modern cryptogamic ground covers (CGCs), comprising assemblages of bryophytes (hornworts, liverworts, mosses), fungi, bacteria, lichens and algae, are thought to resemble early divergent terrestrial communities. However, limited in situ plant and other fossils in the rock record, and a lack of CGC‐like soils reported in the pre‐Silurian sedimentological record, have hindered understanding of the structure, composition and interactions within the earliest CGCs. A key question is how the earliest CGC‐like organisms drove weathering on primordial terrestrial surfaces (regolith), leading to the early stages of soil development as proto‐soils, and subsequently contributing to large‐scale biogeochemical shifts in the Earth System. Here, we employed a novel qualitative, quantitative and multi‐dimensional imaging approach through X‐ray micro‐computed tomography, scanning electron, and optical microscopy to investigate whether different combinations of modern CGC organisms from primordial‐like settings in Iceland develop organism‐specific soil forming features at the macro‐ and micro‐scales. Additionally, we analysed CGCs growing on hard rocky substrates to investigate the initiation of weathering processes non‐destructively in 3D. We show that thalloid CGC organisms (liverworts, hornworts) develop thin organic layers at the surface (<1 cm) with limited subsurface structural development, whereas leafy mosses and communities of mixed organisms form profiles that are thicker (up to ~ 7 cm), structurally more complex, and more organic‐rich. We term these thin layers and profiles proto‐soils. Component analyses from X‐ray micro‐computed tomography data show that thickness and structure of these proto‐soils are determined by the type of colonising organism(s), suggesting that the evolution of more complex soils through the Palaeozoic may have been driven by a shift in body plan of CGC‐like organisms from flattened and appressed to upright and leafy. Our results provide a framework for identifying CGC‐like proto‐soils in the rock record and a new proxy for understanding organism–soil interactions in ancient terrestrial biospheres and their contribution to the early stages of soil formation. [ABSTRACT FROM AUTHOR]

As a large majority of modern green algae are freshwater rather than marine, it can be hypothesized that algae were an important component of early terrestrial environments. However, this component remains overlooked as algal affinities are difficult to decipher, due to the lack of distinctive characters observable in standard light microscopy. Herein, we use a new approach to studying microfossils from the Devonian (407 Ma) Rhynie cherts, renowned as one of the earliest exceptionally preserved terrestrial ecosystem. Using data from confocal laser scanning microscopy, the microfossils were reconstructed in 3D allowing us to gather information on morphological and physiological traits. We document Triskelia scotlandica gen. et sp. nov., which is the resting stage of a new species of microalgae. Numerous individuals were discovered preserved inside the remains of a flooded plant aerial axis. They are shown to be spheroidal to ellipsoidal walled cells, with a pseudo‐reticulate surface ornamentation and occasional large openings probably resulting from the germination process. We draw comparison with fossil and modern microorganisms demonstrating morphological convergences in wall ornament and physiological traits, especially with zygospores of modern Chlorophyta. Our description of Triskelia leads us to critically evaluate the Rhynie chert fossils Cymatiosphaera and Pterospermella. We conclude that it is unlikely that the Rhynie cherts contained prasinophycean algae of these types. We suggest that our microfossils are Chlorophyta (green algae) incertae sedis that were highly adapted to the special ecological conditions encountered in a geothermal wetland. [ABSTRACT FROM AUTHOR]

In humans, histiocytic sarcoma (HS) is an aggressive cancer involving histiocytes. Its rarity and heterogeneity explain that treatment remains a challenge. Sharing high clinical and histopathological similarities with human HS, the canine HS is conversely frequent in specific breeds and thus constitutes a unique spontaneous model for human HS to decipher the genetic bases and to explore therapeutic options. We identified sequence alterations in the MAPK pathway in at least 63.9% (71/111) of HS cases with mutually exclusive BRAF (0.9%; 1/111), KRAS (7.2%; 8/111) and PTPN11 (56.75%; 63/111) mutations concentrated at hotspots common to human cancers. Recurrent PTPN11 mutations are associated to visceral disseminated HS subtype in dogs, the most aggressive clinical presentation. We then identified PTPN11 mutations in 3/19 (15.7%) human HS patients. Thus, we propose PTPN11 mutations as key events for a specific subset of human and canine HS: the visceral disseminated form. Finally, by testing drugs targeting the MAPK pathway in eight canine HS cell lines, we identified a better anti‐proliferation activity of MEK inhibitors than PTPN11 inhibitors in canine HS neoplastic cells. In combination, these results illustrate the relevance of naturally affected dogs in deciphering genetic mechanisms and selecting efficient targeted therapies for such rare and aggressive cancers in humans. What's new? Histiocytic sarcoma (HS) is a rare, aggressive, and heterogeneous cancer, which remains hard to treat. Here, the authors compare genetic alterations between human HS and spontaneously occurring canine HS as a way to home in on mutations important for cancer progression. They identified mutations in the MAPK pathway in a majority of cases, and in particular detected an association between mutations in the PTPN11 gene and one specific HS subtype in both species. They compared the effectiveness of MAP kinase inhibitors in 8 canine cell lines, demonstrating that targeting the MAPK pathway may effectively treat BRAF wild type HS. [ABSTRACT FROM AUTHOR]

Canine oral melanoma is the first malignancy of the oral cavity in dogs and is characterized by a local invasiveness and a high metastatic propensity. A better knowledge of genetic alterations is expected to improve management of this tumour. Copy number alterations are known characteristics of mucosal melanomas both in dogs and humans. The goal of this study was to explore the prognostic value of somatic focal amplifications on chromosomes (Canis Familiaris [CFA]) 10 and 30 in canine oral melanoma. The cohort included 73 dogs with oral melanoma confirmed by histology, removed surgically without adjuvant therapy and with a minimal follow‐up of 6 months. Epidemiological, clinical and histological data were collected and quantitative‐PCR were performed on formalin‐fixed paraffin‐embedded (FFPE) samples to identify specific focal amplifications. The 73 dogs included in the study had a median survival time of 220 days. Focal amplifications on CFA 10 and 30 were recurrent (49.3% and 50.7% of cases, respectively) and CFA 30 amplification was significantly associated with the amelanotic phenotype (P =.046) and high mitotic index (MI; P =.0039). CFA 30 amplification was also linked to poor prognosis (P =.0005). Other negative prognostic factors included gingiva location (P =.003), lymphadenomegaly (P =.026), tumour ulceration at diagnosis (P =.003), MI superior to 6 mitoses over 10 fields (P =.001) and amelanotic tumour (P =.029). In multivariate analyses using Cox proportional hazards regression, CFA 30 amplification (Hazard ratio [HR] = 2.08; P =.011), tumour location (HR = 2.20; P =.005) and histological pigmentation (HR = 1.87; P =.036) were significantly associated with shorter survival time. Focal amplification of CFA 30 is linked to an aggressive subset and constitutes a new prognostic factor. [ABSTRACT FROM AUTHOR]

Nijmegen breakage syndrome caused by biallelic pathogenic variants of the DNA‐damage response gene NBN, is characterized by severe microcephaly, cancer proneness, infertility, and karyotype abnormalities. We previously reported NBN variants in siblings suffering from fertility defects. Here, we identify a new founder NBN variant (c.442A>G, p.(Thr148Ala)) in Lebanese patients associated with isolated infertility. Functional analyses explored preserved or altered functions correlated with their remarkably mild phenotype. Transcript and protein analyses supported the use of an alternative transcript with in‐frame skipping of exons 4–5, leading to p84‐NBN protein with a preserved forkhead‐associated (FHA) domain. The level of NBN was dramatically reduced and the MRN complex delocalized to the cytoplasm. Interestingly, ataxia–elangiectasia mutated (ATM) also shifted from the nucleus to the cytoplasm, suggesting some interaction between ATM and the MRN complex at a steady state. The ATM pathway activation, attenuated in typical patients with NBS, appeared normal under camptothecin treatment in these new NBN‐related infertile patients. Cell cycle checkpoint defect was present in these atypical patients, although to a lesser extent than in typical patients with NBS. In conclusion, we report three new NBN‐related infertile patients and we suggest that preserved FHA domain could be responsible for the mild phenotype and intermediate DNA‐damage response defects. [ABSTRACT FROM AUTHOR]

In September 2016, Piton de la Fournaise volcano, well known for its effusive and Hawaiian fountaining activity, produced, at the end of the eruption, an unusual phase of pulsating ash and bomb emission. Integration of geophysical data, with textural and petrological analysis of the samples, allowed us to constrain the main factors that controlled this sudden shift in activity, potentially dangerous for the tourist population that usually approach these "gentle" eruptive sites. Volcanic tremor, lava discharge rates, fountain heights, and SO2 emission changed rapidly during the eruption. Grain size and componentry of the tephra beds evolved from unimodal all along the sequence to bimodal on the last day of the activity, reflecting the contribution of both Hawaiian fountaining at the main vent (Vent A) and transient explosive activity at the second vent (Vent B). Hawaiian fountaining produced highly vesicular and almost microlite‐free tephra (golden pumice and fluidal scoria) while transient explosive activity emitted denser and crystal‐rich tephra (sideromelane and tachylite scoria) sometimes mingled with vesicular fragments. Permeability measurements on lapilli and bomb‐sized samples reveal that golden pumice and fluidal scoria were more gas‐permeable than the sideromelane and tachylite ones, while textural and chemical analyses of the ash support the hypothesis that these sideromelane and tachylite components were inherited from the subsurface crystallization of the initial golden pumice and fluidal scoria components. We thus suggest that Vent B accumulated a plug of degassed, cooled, and low‐permeable magma, which modulated overpressure pulses under the late input of ascending magma. Key Points: Syn‐eruptive transition from Hawaiian fountaining to transient ash explosions is marked by shallow magmatic degassing and crystallizationDegassed, crystallized, and impermeable shallow magmatic layers can potentially form and burry vents with low eruptive activityGeophysical and geochemical monitoring evidenced a late arrival of a magma that pressurized the buried vent triggering ash explosions [ABSTRACT FROM AUTHOR]

A number of firms in the United Kingdom list without issuing equity and then issue equity shortly thereafter. We argue that this two-stage offering strategy is less costly than an initial public offering (IPO) because trading reduces the valuation uncertainty of these firms before they issue equity. We find that initial returns are 10% to 30% lower for these firms than for comparable IPOs, and we provide evidence that the market in the firm's shares lowers financing costs. We also show that these firms time the market both when they list and when they issue equity. [ABSTRACT FROM AUTHOR]

This paper explores the impact of investor sentiment on IPO pricing. Using a model in which the aftermarket price of IPO shares depends on the information about the intrinsic value of the company and investor sentiment, I show that IPOs can be overpriced and still exhibit positive initial return. A sample of recent French offerings with a fraction of the shares reserved for individual investors supports the predictions of the model. Individual investors' demand is positively related to market conditions. Moreover, large individual investors' demand leads to high IPO prices, large initial returns, and poor long-run performance. [ABSTRACT FROM AUTHOR]

The MICOS Compton spectrometer is a tool for the routine spectrometric control of X‐ray generators, mainly in the medical field (<150 kV). The use of a pen‐type NaI (Tl) detector with thin Be window allows to extend its range down to 6 keV, for a better evaluation of the low‐E side of the spectrum, which is determined by filtration. A specific problem is encountered in the deconvolution of the spectrum at very low energies, dominated by the K escape of iodine. The proposed solution combines an approximate step‐by‐step application of the GRAVEL algorithm, whereas the MAXED unfolding software is used for reaching the final solution. A new computer code was developed that combines spectrum acquisition and deconvolution and calculates the main characteristics of the source spectrum: end point energy, mean energy, energy at 50% of the left slope, and air kerma at 1 m from the source. [ABSTRACT FROM AUTHOR]

ContentsSummary1012I.Introduction1013II.The mycorrhizal symbiosis at the dawn and rise of the land flora1014III.From early land plants to early trees: the origin of roots and true mycorrhizas1016IV.The diversification of the AM symbiosis1019V.The ECM symbiosis1021VI.The recently evolved ericoid and orchid mycorrhizas1023VII.Limits of paleontological vs genetic approaches and perspectives1023Acknowledgements1025References1025 Summary: The ability of fungi to form mycorrhizas with plants is one of the most remarkable and enduring adaptations to life on land. The occurrence of mycorrhizas is now well established in c. 85% of extant plants, yet the geological record of these associations is sparse. Fossils preserved under exceptional conditions provide tantalizing glimpses into the evolutionary history of mycorrhizas, showing the extent of their occurrence and aspects of their evolution in extinct plants. The fossil record has important roles to play in establishing a chronology of when key fungal associations evolved and in understanding their importance in ecosystems through time. Together with calibrated phylogenetic trees, these approaches extend our understanding of when and how groups evolved in the context of major environmental change on a global scale. Phylogenomics furthers this understanding into the evolution of different types of mycorrhizal associations, and genomic studies of both plants and fungi are shedding light on how the complex set of symbiotic traits evolved. Here we present a review of the main phases of the evolution of mycorrhizal interactions from palaeontological, phylogenetic and genomic perspectives, with the aim of highlighting the potential of fossil material and a geological perspective in a cross‐disciplinary approach. [ABSTRACT FROM AUTHOR]

Coastal zones are vital for their ecosystem services and socioeconomic value. Accordingly, several zones have been protected to limit anthropogenic development and to avoid environmental degradation. Nevertheless, some of these protected areas keep deteriorating probably related with anthropogenic contributions not considered in legislation. Specifically, submerged groundwater discharges (springs) could be releasing anthropogenic materials carried from remote inland areas to the coast. Here we evaluate the role and temporal variation of submerged groundwater discharges as sources of anthropogenic materials using the 5β-stanol C27 markers in the natural protected area of Dzilam de Bravo, Yucatán, Mexico. Results demonstrate that (1) submerged groundwater discharge flux velocity and direction vary between hydrological season, exhibiting higher flow rates in Nortes season contrary to dry season and (2) the presence of coprostanol and epicoprostanol (anthropogenic fecal matter markers) in sediments surrounding the submerged groundwater discharges provides proof of allochthonous anthropogenic fecal material in a protected area, probably from remote inland sites. Thus, it is vitally important that inland anthropogenic materials transported in groundwater and released in the coastal environment by submerged groundwater discharges be considered in protection plans, like protection perimeters, for coastal zones. [ABSTRACT FROM AUTHOR]

The genome of the filamentous brown alga Ectocarpus was the first to be completely sequenced from within the brown algal group and has served as a key reference genome both for this lineage and for the stramenopiles., We present a complete structural and functional reannotation of the Ectocarpus genome., The large-scale assembly of the Ectocarpus genome was significantly improved and genome-wide gene re-annotation using extensive RNA-seq data improved the structure of 11 108 existing protein-coding genes and added 2030 new loci. A genome-wide analysis of splicing isoforms identified an average of 1.6 transcripts per locus. A large number of previously undescribed noncoding genes were identified and annotated, including 717 loci that produce long noncoding RNAs. Conservation of lnc RNAs between Ectocarpus and another brown alga, the kelp Saccharina japonica, suggests that at least a proportion of these loci serve a function. Finally, a large collection of single nucleotide polymorphism-based markers was developed for genetic analyses. These resources are available through an updated and improved genome database., This study significantly improves the utility of the Ectocarpus genome as a high-quality reference for the study of many important aspects of brown algal biology and as a reference for genomic analyses across the stramenopiles. [ABSTRACT FROM AUTHOR]

RATIONALE: We compared gas chromatography/isotope ratio mass spectrometry (GC/IRMS) and liquid chromatography/isotope ratio mass spectrometry (LC/IRMS) for the measurement of δ13C values in carbohydrates. Contrary to GC/IRMS, no derivatisation is needed for LC/IRMS analysis of carbohydrates. Hence, although LC/IRMS is expected to be more accurate and precise, no direct comparison has been reported. METHODS: GC/IRMS with the aldonitrile penta-acetate (ANPA) derivatisation method was compared with LC/IRMS without derivatisation. A large number of glucose standards and a variety of natural samples were analysed for five neutral carbohydrates at natural abundance as well as at 13C-enriched levels. Gas chromatography/chemical ionisation mass spectrometry (GC/CIMS) was applied to check for incomplete derivatisation of the carbohydrate, which would impair the accuracy of the GC/IRMS method. RESULTS: The LC/IRMS technique provided excellent precision (±0.08 ‰ and ±3.1 ‰ at natural abundance and enrichment levels, respectively) for the glucose standards and this technique proved to be superior to GC/IRMS (±0.62 ‰ and ±19.8 ‰ at natural abundance and enrichment levels, respectively). For GC/IRMS measurements the derivatisation correction and the conversion of carbohydrates into CO2 had a considerable effect on the measured δ13C values. However, we did not find any significant differences in the accuracy of the two techniques over the full range of natural δ13C abundances and 13C-labelled glucose. The difference in the performance of GC/IRMS and LC/IRMS diminished when the δ13C values were measured in natural samples, because the chromatographic performance and background correction became critical factors, particularly for LC/IRMS. The derivatisation of carbohydrates for the GC/IRMS method was complete. CONCLUSIONS: Although both LC/IRMS and GC/IRMS are reliable techniques for compound-specific stable carbon isotope analysis of carbohydrates (provided that derivatisation is complete and the calibration requirements are met), LC/IRMS is the technique of choice. The reasons for this are the improved precision, simpler sample preparation, and straightforward isotopic calibration. [ABSTRACT FROM AUTHOR]

Information regarding the 10th New Phytologist Workshop on the "Origin and evolution of plants and their interactions with fungi" that was held at The Natural History Museum in London, England from September 9-10, 2014 is presented. Topics discussed include the symbiosis between a green alga and photosynthetic abilities, biogeochemical cycles, and fungi recycling plant remains. The workshop featured several phytology professionals including Dianne Edwards, Christopher Berry, and Mary Berbee.

To support the Megha-Tropiques space mission, cloud mask and cloud type classification are needed at high spatial and time resolutions over the tropical belt for water vapour and precipitation analysis. For this purpose, visible and infrared radiance data from geostationary satellites ( GEO) are used with a single algorithm initially developed by SAFNWC (Satellite Application Facility for Nowcasting) for Meteosat Second Generation. This algorithm has been adapted by SAFNWC to the spectral characteristics and field of view of each satellite. Retrieved cloud cover characteristics (cloud mask, classification and top pressure) are evaluated over four months in summer of 2009 against CALIOP lidar observations from the CALIPSO polar-orbiting satellite. To better identify atmospheric and instrumental issues, separate analyses are performed over land and ocean, for 1:30 a.m. and 1:30 p.m. CALIPSO overpasses and for each GEO. Both mean cloud-cover occurrence and instantaneous cloud-cover statistics are compared. We found that each classification has specific features, which depend on observed cloud regimes and instrument capabilities. Most important, a common behaviour of the GEOs against CALIOP depending on cloud type is observed. We found that GEO cloud occurrence is lower by about 10% than for CALIOP, with the largest biases over land during daytime and the smallest over ocean during daytime. Further detailed analysis reveals specific discrepancies in the retrieved cloud types. As expected, high-level clouds are detected more frequently by the lidar. We show that, over ocean when the optical thickness of detected high-level clouds is limited to greater than 0.1 in the comparisons, multi-spectral radiometry performs very similarly. However, the most significant difference is attributed to non-detection of low-level clouds that are often broken, which causes a reduction of up to 20% in low-level cloud fraction and even 30% in some regions. Other significant differences are seen over land, where mid-level clouds are not detected or are misclassified. [ABSTRACT FROM AUTHOR]

• Fungi (Eumycota) form close associations with plants, with which they have co-existed since the dawn of life on land, but their diversity in early terrestrial ecosystems is still poorly understood. • We studied petrographic sections of exceptionally well-preserved petrified plants from the 407 million yr-old Rhynie Chert (Scotland, UK). For comparative purposes, we illustrate fungal associations in four extant lower land plants. • We document two new endophytes in the plant Horneophyton lignieri: Palaeoglomus boullardii (sp. nov. Glomeromycota) colonizes parenchyma in a discontinuous zone of the outer cortex of the aerial axes, forming arbuscule-like structures, vesicles and spores; Palaeoendogone gwynne-vaughaniae (gen. nov., sp. nov. Mucoromycotina) colonizes parenchyma in the basal part of the plant, where it is present in intercellular spaces and as intracellular coils but absent from rhizoids. • Critical comparisons between the newly discovered Horneophyton endophytes, fungi previously described from the Rhynie Chert and fungal colonization in extant lower land plants reveal several features characteristic of both Mucoromycotina and Glomeromycota. A reappraisal of fungal associations in early land plants indicates that they are more diverse than assumed hitherto, overturning the long-held paradigm that the early endophytes were exclusively Glomeromycota. [ABSTRACT FROM AUTHOR]

A mild protocol has been developed for the PdII-catalyzed alkoxycarbonylation of terminal olefins to produce α,β-unsaturated esters with a wide range of substrates. Key features are the use of MeCN as solvent (and/or ligand) to control the reactivity of the intermediate Pd complexes and the combination of CO with O2, which facilitates the CuII-mediated reoxidation of the Pd0 complex to PdII and prevents double carbonylation. [ABSTRACT FROM AUTHOR]

The multiparametric nature of nanoparticle self-assembly makes it challenging to circumvent the instabilities that lead to aggregation and achieve crystallization under extreme conditions. By using non-base-pairing DNA as a model ligand instead of the typical base-pairing design for programmability, long-range 2D DNA-gold nanoparticle crystals can be obtained at extremely high salt concentrations and in a divalent salt environment. The interparticle spacings in these 2D nanoparticle crystals can be engineered and further tuned based on an empirical model incorporating the parameters of ligand length and ionic strength. [ABSTRACT FROM AUTHOR]

Transport per Flügelrad: Der durch einen Zweiphotonenprozess ausgelöste Camptothecin ‐ Transport in MCF ‐ 7 ‐ Krebszellen mithilfe von Nanoimpellern (siehe Bild) wurde untersucht. Ein Fluorophor mit einem großen Zweiphotonenabsorptionsquerschnitt wurde zunächst in die Nanoimpeller eingebaut. Zwischen dem Fluorophor und der Azobenzol ‐ Einheit fand ein resonanter Fluoreszenzenergietransfer (FRET) statt. [ABSTRACT FROM AUTHOR]

Innate and adaptive mucosal defense mechanisms ensure a homeostatic relationship with the large and complex mutualistic gut microbiota. Dimeric IgA and pentameric IgM are transported across the intestinal epithelium via the epithelial polymeric Ig receptor (pIgR) and provide a significant portion of the first line of natural or adaptive antibody-mediated immune defense of the intestinal mucosa. We found that colonic epithelial cells from pIgR KO mice differentially expressed (more than twofold change) more than 200 genes compared with cells from WT mice, and upregulated the expression of antimicrobial peptides in a commensal-dependent manner. Detailed profiling of microbial communities based on 16S rRNA genes revealed differences in the commensal microbiota between pIgR KO and WT mice. Furthermore, we found that pIgR KO mice showed increased susceptibility to dextran sulfate sodium-induced colitis, and that this was driven by their conventional intestinal microbiota. Thus, in the absence of pIgR, the stability of the commensal microbiota is disturbed, gut homeostasis is compromised, and the outcome of colitis is significantly worsened. [ABSTRACT FROM AUTHOR]

This study investigated whether the synthetic peptide B2A (B2A2-K-NS) could induce in vitro chondrogenic differentiation and enhance the in vivo repair of damaged cartilage in an osteoarthritis model. In vitro, micromass cultures of murine and human stem cells with and without B2A were used as models of chondrogenic differentiation. Micromasses were evaluated for gene expression using microarray analysis and quantitative PCR; and for extracellular matrix production by Alcian blue staining for sulfated glycosaminoglycan and immunochemical detection of collagen type II. In vivo, osteoarthritis was chemically induced in knees of adult rats by an injection of mono-iodoacetate (MIA) into the synovial space. Treatment was administered at 7- and 14 days after the MIA by injection into the synovial space of B2A or saline and terminated at 21 days, after which knee cartilage damage was determined and scored by histological analysis. In murine C3H10T1/2 micromass culture, B2A induced the expression of more than 11 genes associated with growth factors/receptors, transcription, and the extracellular matrix, including PDGF-AA. B2A also significantly increased the sulfated glycosaminoglycan and collagen of murine- and human micromass cultures. In the knee osteoarthritis model, B2A treatment enhanced cartilage repair compared to untreated knees as determined histologically by a decrease in damage indicators. These findings suggest that B2A induces stem cells chondrogenic differentiation in vitro and enhances cartilage repair in vivo. The results suggest that B2A might be useful to promote cartilage repair. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 30:1221-1228, 2012 [ABSTRACT FROM AUTHOR]

Summary The endogenous gut microbiota affects the host in many ways. Prebiotics should favour beneficial intestinal microbes and thus improve host health. In this study, we investigated how a novel class of potential prebiotic long-chain arabinoxylans (LC-AX) and the well-established prebiotic inulin (IN) modulate the gut microbiota of humanized rats. Six weeks after axenic rats were inoculated with a human faecal microbiota, their colonic microbiota was similar to this inoculum (∼ 70%), whereas their caecal microbiota was enriched with Verrucomicrobia and Firmicutes concomitant with lower abundance of Bacteroidetes. Moreover, different Bifidobacterium species colonized the lumen ( B. adolescentis) and mucus ( B. longum and B. bifidum). Both LC-AX and IN increased SCFA levels and induced a shift from acetate towards health-promoting propionate and butyrate respectively. By applying a high-resolution phylogenetic micro-array (HITChip) at the site of fermentation (caecum), IN and LC-AX were shown to stimulate bacterial groups with known butyrate-producers ( Roseburia intestinalis, Eubacterium rectale, Anaerostipes caccae) and bifidobacteria ( B. longum) respectively. Prebiotic administration also resulted in lower caecal abundances of the mucin-degrading Akkermansia muciniphila and potentially more mucin production by the host. Both factors might explain the increased caecal mucin levels for LC-AX (threefold) and IN (sixfold). These mucins were degraded along the colon, resulting in high faecal abundances of Akkermansia muciniphila for LC-AX and especially IN-treated rats. Finally, the microbial changes caused an adaptation period for the host with less weight gain, after which the host fine-tuned the interaction with this altered microbiota. Our results demonstrate that next to IN, LC-AX are promising prebiotic compounds by stimulating production of health-promoting metabolites by specific microbes in the proximal regions. Further, prebiotic supplementation shifted mucin degradation to distal regions, where mucin-degraders may produce beneficial metabolites (e.g. propionate by Akkermansia muciniphila), so that prebiotics may potentially improve gut health along the entire length of the intestine. [ABSTRACT FROM AUTHOR]

The article discusses a study on fecal contamination in surface waters which was evaluated through the enumeration of the fecal coliforms Escherichia coli and Enterococci. It cites indicators of fecal contamination, including microbial markers and chemical fingerprints to determine contamination of livestock in surface waters with the use of artificial rainfall simulator. It indicates that swine-slurry-amended soils released low amounts of bacterial indicators in runoff water while cattle-manure-amended soils released greater amounts of indicators.

Soils contain the largest carbon (C) reservoir on Earth, but the mean residence time (MRT) of soil C is often poorly estimated, despite its importance for assessing the efficiency with which soils may serve as a sink for atmospheric C. The objective of this study was to evaluate how the structure of simple models of soil C dynamics affects the MRT determined from isotope-mixing experiments, using data from field studies with either artificial labelling (FACE) or C3/C4 vegetation change. We first highlighted theoretically how non-steady-state conditions and the model structure (one single, two successive, or two parallel C pools) can have an impact on the MRT assessment. We then tested these different model structures against published data on the dynamics of different soil organic matter separates and their constituents. Our findings indicated that many of the reviewed studies assumed wrongly that the system was at steady state or could be described by a single-pool approach. To select the correct model, exact knowledge of C input rates and several data points are needed from the beginning of the experiment. For steady-state conditions an apparent temporal change of MRT computed from a single-pool model is thus a clear indicator that a two-pool approach must be chosen. The errors made by the wrong choice of model varied with the length of the experiment and usually resulted in an over-estimate of MRT by a factor of 1.15 for some data published on physical size separates, but by a factor of up to 11 for individual microbial biomarkers such as muramic acid. [ABSTRACT FROM AUTHOR]

Vibrio parahaemolyticus is one of the principal bacterial causes for seafood-borne gastroenteritis in the world. In the present study, three sites located on the French Atlantic coast were monitored monthly for environmental parameters over 1 year. The presence of total and pathogenic V. parahaemolyticus in sediment, water and mussel samples was detected following enrichment by culture and real-time PCR ( toxR gene, tdh, trh1 and trh2 virulence genes). Using generalized linear models, we showed that the presence of V. parahaemolyticus in water could be explained by a combination of mean temperature over the 7 days before the day of sampling ( P < 0.001) and turbidity ( P = 0.058). In mussels, an effect of chlorophyll a ( P = 0.005) was detected when an effect of the mean salinity over the 7 days before sampling was significant for the sediment ( P < 0.001). We did not detect any significant effect of phytoplanktonic blooms or of the number of culturable bacteria on V. parahaemolyticus presence. No sample was revealed positive for tdh. The presence of trh1 and trh2 was positively influenced by the mean temperature during the 2 days before the day of sampling ( P < 0.001 and P = 0.032). The importance of these ecological parameters is discussed in relation to the biology of V. parahaemolyticus. [ABSTRACT FROM AUTHOR]

Summary The present study focused on the isolation of culturable bacteria from mussels and sea water to identify Vibrionaceae potentially pathogenic for humans. Three sites located on the French Atlantic coast were monitored monthly (twice each month during summer) for 1 year. Environmental parameters were surveyed (water temperature, salinity, turbidity, chlorophyll a) and bacteria were detected by culture and identified by API 20E® systems (BioMérieux) and PCR. A total of seven species were detected ( Grimontia hollisae, Photobacterium damselae, Vibrio alginolyticus, V. cholerae, V. fluvialis, V. vulnificus and V. parahaemolyticus) and species diversity was higher at the end of summer. Surprisingly, V. cholerae non-O1/non-O139 was detected in spring. No site effect was detected. Using Sørensen similarity indices and statistical analyses, we showed that chlorophyll a had a significant influence on the bacterial community detected in mussels and assemblages were more similar to one another when chlorophyll a values were above 20 µg l−1. No significant effect of any parameter was found on the community detected in water samples. Such surveys are essential for the understanding of sanitary crises and detection of emerging pathogens. [ABSTRACT FROM AUTHOR]

We study the extent to which investor sentiment matters for aggregate equity issuance activity. We focus on firms that are susceptible to investor sentiment and for which accurate measures of economic fundamentals are available. While sentiment on its own matters for equity issuance, it matters relatively little once we control for accurately measured fundamentals. Collectively, proxies for sentiment explain roughly 10 percentage points of the time-series variation of equity issuance beyond the roughly 40% explained by fundamentals. We conclude that investor sentiment does not seem to matter very much for aggregate equity issuance activity. [ABSTRACT FROM AUTHOR]

A letter entitled "Mycorrhizas in Upper Carboniferous Radiculites-Type Cordaitalean Rootlets," by Christine Strullu-Derrien, Jean-Philippe Rioult, and Désiré-Georges Strullu, discusses fungal associations with plants.

Understanding the chemical composition of soil organic matter (SOM) requires the determination of the dynamics of each class of compounds. We measured the dynamics of carbon in neutral carbohydrates by use of natural 13C labelling in an experimental wheat and maize sequence extending over 23 years. The isotopic composition of individual neutral monosaccharides was determined in hydrolysed particle-size fractions by gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS) of trimethylsilyl (TMS) derivatives. The sensitivity in terms of 13C/12C ratios ranged between 1 and 2‰ depending on the monosaccharide. The age distribution of neutral sugar carbon was very similar to that of total soil carbon. Particulate organic matter (POM) was characterized by the predominance of glucose and xylose of vegetal origin. In POM > 200 µm, the mean age of sugar-C (5 years) was slightly less than that of total carbon (7 years). Xylose was younger than glucose. The fine fraction 0–50 µm contained mainly glucose, arabinose, galactose, xylose, fucose and mannose, which had predominantly microbial origins. The mean age of carbohydrate carbon in the fraction 0–50 µm was between 60 and 100 years and was similar to that of total organic carbon (OC). No difference in the age of carbon between the individual monosaccharides was found. The POM fraction 50–200 µm had an intermediate signature and turnover. Considering the typical lability of carbohydrates, the relatively great age of carbohydrate carbon may be explained by physical or chemical protection from degradation, as well as by recycling of soil organic matter carbon by soil microbes. [ABSTRACT FROM AUTHOR]

Intracytoplasmic sperm injection (ICSI) is now widely acknowledged as the most effective therapeutic approach to severe male infertility or unsuccessful in vitro fertilization. Cytogenetic investigations were performed in 370 females and 335 males prior to ICSI between January 1997 and April 2003. Nine men (2.7%) and 48 women (13%) had an abnormal karyotype, 44 females having some degree of numerical sex chromosome mosaicism. A review of the literature showed the prevalence of all types of chromosomal abnormalities to be much higher among male and female partners of couples examined prior to ICSI than among newborns. As most ICSIs are performed with ejaculated spermatozoa from oligospermic men, the distribution and the prevalence of the several types of chromosomal abnormalities are closer to those of oligospermic rather than azoospermic males. Our results combined with those of the literature stress the importance of karyotyping both male and female partners before ICSI is started. Adequate genetic counselling, possibly followed by prenatal diagnosis, should be offered if a chromosomal anomaly is detected. [ABSTRACT FROM AUTHOR]