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AbstractThis pilot study investigated the feasibility of an occupational therapist-facilitated seven-week online support group with problem-solving training on the psychosocial well-being of parental caregivers of individuals with spinal cord injury (SCI). The study used a single-group pre-test/post-test quantitative design. A convenience sample of five participants, who each identified as mothers of male individuals with SCI, completed the study. From pre to post, participants demonstrated high satisfaction with the group, decreased stress, increased knowledge, and an increase in problem-focused coping strategies, yet no changes were greater than minimal detectable change. [ABSTRACT FROM AUTHOR]

Agricultural practices have created tens of millions of small artificial water bodies ("farm dams" or "agricultural ponds") to provide water for domestic livestock worldwide. Among freshwater ecosystems, farm dams have some of the highest greenhouse gas (GHG) emissions per m2 due to fertilizer and manure run‐off boosting methane production—an extremely potent GHG. However, management strategies to mitigate the substantial emissions from millions of farm dams remain unexplored. We tested the hypothesis that installing fences to exclude livestock could reduce nutrients, improve water quality, and lower aquatic GHG emissions. We established a large‐scale experiment spanning 400 km across south‐eastern Australia where we compared unfenced (N = 33) and fenced farm dams (N = 31) within 17 livestock farms. Fenced farm dams recorded 32% less dissolved nitrogen, 39% less dissolved phosphorus, 22% more dissolved oxygen, and produced 56% less diffusive methane emissions than unfenced dams. We found no effect of farm dam management on diffusive carbon dioxide emissions and on the organic carbon in the soil. Dissolved oxygen was the most important variable explaining changes in carbon fluxes across dams, whereby doubling dissolved oxygen from 5 to 10 mg L−1 led to a 74% decrease in methane fluxes, a 124% decrease in carbon dioxide fluxes, and a 96% decrease in CO2‐eq (CH4 + CO2) fluxes. Dams with very high dissolved oxygen (>10 mg L−1) showed a switch from positive to negative CO2‐eq. (CO2 + CH4) fluxes (i.e., negative radiative balance), indicating a positive contribution to reduce atmospheric warming. Our results demonstrate that simple management actions can dramatically improve water quality and decrease methane emissions while contributing to more productive and sustainable farming. [ABSTRACT FROM AUTHOR]

Monometallic and bimetallic Pt-based electrocatalysts were synthesized via a wet impregnation method using graphene (Gr) as the support and characterized by spectroscopic, imaging, and electrochemical means. The performance of a Pt/Gr catalyst was compared with that of PtRu/Gr and PtSn/Gr catalysts for the electrocatalytic oxidation of methanol. Although Pt monometallic catalysts exhibit sufficient electrocatalytic activity during methanol oxidation, degradation problems associated with surface poisoning processes by reaction side products limit their perspective for commercial use. Alloying Pt with other metals appears to be an effective method for producing highly active electrocatalysts for the same reaction. Physicochemical characterization reveals the incorporation of Sn atoms into the Pt lattice. We provide an in-depth investigation of graphene-based catalysts during the oxidation reaction of methanol, which is a promising fuel for direct alcohol fuel cells. In conjunction with the literature, our results demonstrate that the interaction between metal particles and carbon support is of paramount importance for electrode stability and catalytic performance. Critically, the electrocatalytic activity dependeds on the details of the electrode surface structure and electronic interaction – charge transfer between metal nanoparticles and graphene. It is also proposed that high specific surface area graphene support can facilitate methanol diffusion to the catalyst active sites leading to high electrochemical activity. This work also demonstrates that a low-cost metal, like Sn, can effectively replace Ru to prepare bimetallic Pt-based electrocatalysts for methanol oxidation. The electrocatalytic activity of the Pt–Sn catalyst was found to be similar to that of the Pt-Ru one. [ABSTRACT FROM AUTHOR]

Larger cells have larger nuclei, but the precise relationship between cell size and nucleus size remains unclear, and the evolutionary forces that shape this relationship are debated. We compiled data for almost 900 species – from yeast to mammals – at three scales of biological organisation: among‐species, within‐species, and among‐lineages of a species that was artificially selected for cell size. At all scales, we showed that the ratio of nucleus size to cell size (the 'N: C' ratio) decreased systematically in larger cells. Size evolution appears more constrained in nuclei than cells: cell size spans across six orders of magnitude, whereas nucleus size varies by only three. The next important challenge is to determine the drivers of this apparently ubiquitous relationship in N:C ratios across such a diverse array of organisms. [ABSTRACT FROM AUTHOR]

Summary: Cell size influences the rate at which phytoplankton assimilate dissolved inorganic carbon (DIC), but it is unclear whether volume‐specific carbon uptake should be greater in smaller or larger cells. On the one hand, Fick's Law predicts smaller cells to have a superior diffusive CO2 supply. On the other, larger cells may have greater scope to invest metabolic energy to upregulate active transport per unit area through CO2‐concentrating mechanisms (CCMs).Previous studies have focused on among‐species comparisons, which complicates disentangling the role of cell size from other covarying traits. In this study, we investigated the DIC assimilation of the green alga Dunaliella tertiolecta after using artificial selection to evolve a 9.3‐fold difference in cell volume. We compared CO2 affinity, external carbonic anhydrase (CAext), isotopic signatures (δ13C) and growth among size‐selected lineages.Evolving cells to larger sizes led to an upregulation of CCMs that improved the DIC uptake of this species, with higher CO2 affinity, higher CAext and higher δ13C. Larger cells also achieved faster growth and higher maximum biovolume densities.We showed that evolutionary shifts in cell size can alter the efficiency of DIC uptake systems to influence the fitness of a phytoplankton species. [ABSTRACT FROM AUTHOR]

Size and metabolism are highly correlated, so that community energy flux might be predicted from size distributions alone. However, the accuracy of predictions based on interspecific energy-size relationships relative to approaches not based on size distributions is unknown. We compare six approaches to predict energy flux in phytoplankton communities across succession: assuming a constant energy use among species (per cell or unit biomass), using energy-size interspecific scaling relationships and speciesspecific rates (both with or without accounting for density effects). Except for the per cell approach, all others explained some variation in energy flux but their accuracy varied considerably. Surprisingly, the best approach overall was based on mean biomass-specific rates, followed by the most complex (species-specific rates with density). We show that biomass-specific rates alone predict community energy flux because the allometric scaling of energy use with size measured for species in isolation does not reflect the isometric scaling of these species in communities. We also find energy equivalence throughout succession, even when communities are not at carrying capacity. Finally, we discuss that species assembly can alter energy-size relationships, and that metabolic suppression in response to density might drive the allometry of community energy flux as biomass accumulates. [ABSTRACT FROM AUTHOR]

Body size often declines with increasing temperature. Although there is ample evidence for this effect to be adaptive, it remains unclear whether size shrinking at warmer temperatures is driven by specific properties of being smaller (e.g., surface to volume ratio) or by traits that are correlated with size (e.g., metabolism, growth). We used 290 generations (22 months) of artificial selection on a unicellular phytoplankton species to evolve a 13‐fold difference in volume between small‐selected and large‐selected cells and tested their performance at 22°C (usual temperature), 18°C (−4), and 26°C (+4). Warmer temperatures increased fitness in small‐selected individuals and reduced fitness in large‐selected ones, indicating changes in size alone are sufficient to mediate temperature‐dependent performance. Our results are incompatible with the often‐cited geometric argument of warmer temperature intensifying resource limitation. Instead, we find evidence that is consistent with larger cells being more vulnerable to reactive oxygen species. By engineering cells of different sizes, our results suggest that smaller‐celled species are pre‐adapted for higher temperatures. We discuss the potential repercussions for global carbon cycles and the biological pump under climate warming. [ABSTRACT FROM AUTHOR]

Body size often strongly covaries with demography across species. Metabolism has long been invoked as the driver of these patterns, but tests of causal links between size, metabolism and demography within a species are exceedingly rare. We used 400 generations of artificial selection to evolve a 2427% size difference in the microalga Dunaliella tertiolecta. We repeatedly measured size, energy fluxes and demography across the evolved lineages. Then, we used standard metabolic theory to generate predictions of how size and demography should covary based on the scaling of energy fluxes that we measured. The size dependency of energy remained relatively consistent in time, but metabolic theory failed to predict demographic rates, which varied unpredictably in strength and even sign across generations. Classic theory holds that size affects demography via metabolism – our results suggest that both metabolism and size act separately to drive demography and that among‐species patterns may not predict within‐species processes. [ABSTRACT FROM AUTHOR]

• Landsat water indices (WIs) assessed growth in time of small water storages (SMS) • WIs' analyses defined construction year of > 700,000 SMS in the Murray-Darling Basin. • SMS volume grew more than twofold since the 1990 s to 2,629.5 million cubic metres. • Growth accelerated during the 'Millennium Drought' (2001–2009) at ∼ 2.5% per annum. • Findings can be used to improve hydrologic modelling of the catchment impacts of SMS. Water demand for agricultural activities has caused a growth in small on-farm storages (i.e., ≥ 0.1 ha to ≤ 10 ha) in many areas worldwide, thereby increasing the capture of landscape runoff which otherwise would enter the catchment drainage system. The cumulative effects of these on-farm storages (colloquially known as farm ponds or farm dams) can result in reduced mean annual flows, particularly during dry years. Climate change, which will very likely exacerbate extreme weather conditions including droughts, may accelerate the growth of farm dams in semi-arid agricultural areas with limited access to surface water. The aim of this study is to evaluate farm dam development and total farm dam water volumes at regional scales using Landsat water indices (WIs). The Murray-Darling Basin (MDB, 1.061 million km2) in south and eastern Australia, which has experienced a sustained growth in farm dams in the 1990s and early 2000s, is used as a case study. Using a pixel validation dataset, four WIs were trialled for their capabilities to detect the presence of water in farm dams. Of the WIs tested here, AWEI shadow showed the best performance. As a result, AWEI shadow was used to establish the year in which water was first observed (i.e., its year of commission) in 727,081 farm dams across the MDB and to calculate the total farm dam volume in the region. Farm dams' volume in the MDB increased more than twofold between 1990 and 2020, from 1241.0 MCM (million cubic meters) to 2,629.5 MCM. The growth differed across MDB regions, generally accelerating during the 'Millennium Drought' (2001–2009). In the entire MDB, there was rapid development in the 1990s with 3.1% growth. Growth was 2.5% from 2000 to 2010, tapering off to 0.6% from 2010 to 2020. In Robertson et al. (this issue), the year-by-year growth in farm dams' volume were used in a rainfall-runoff model thereby incorporating the time-varying effects of farm dams. Robertson et al. (this issue) show that explicitly modelling farm dams improves the model's performance relative to a traditional rainfall-runoff model that ignores the effects of farm dams. Hence, this improves the capability of assessing the direct impacts of farm dams and their potential growth in climate change studies. [ABSTRACT FROM AUTHOR]

Habitat loss is a key factor in the ongoing freshwater biodiversity crisis. A promising way to help tackle the rapid decline in freshwater biodiversity is to improve the potential for artificial wetlands to provide habitat for aquatic wildlife. Farm dams (also known as agricultural ponds) are among the most abundant waterbodies in agricultural landscapes and can act as "oases" against droughts for many species. Despite their prominent role in agriculture, predictive models to evaluate their ecological potential are yet to emerge. Here we use a continental-scale data set of 104,013 audio recordings from citizen scientists to identify and locate 107 species of frogs near 8800 Australian farm dams. Frog species are among the most threatened taxa on earth and we asked: What characteristics promote higher frog species richness at farm dams ? We found that the highest values of frog species richness were at old (>20 years) farm dams of intermediate size (0.1 ha in surface area), with small or medium rainfall catchments (<10 ha), and situated near other freshwater systems or conservation sites. The relationships shown here are highly generalisable and applicable on a continental scale. By identifying quantifiable features improving the ecological value of farm dams, we help identify "win-win" outcomes for agricultural productivity and conservation. In the future, "biodiversity credit" policies could incentivise large-scale ecological restoration by rewarding individuals who invest in enhancing their farm dams to support and promote local biodiversity. [ABSTRACT FROM AUTHOR]

Size determines the rate at which organisms acquire and use resources but it is unclear what size should be favoured under unpredictable resource regimes. Some theories claim smaller organisms can grow faster following a resource pulse, whereas others argue larger species can accumulate more resources and maintain growth for longer periods between resource pulses. Testing these theories has relied on interspecific comparisons, which tend to confound body size with other life-history traits. As a more direct approach, we used 280 generations of artificial selection to evolve a 10-fold difference in mean body size between small- and large-selected phytoplankton lineages of Dunaliella tertiolecta, while controlling for biotic and abiotic variables. We then quantified how body size affected the ability of this species to grow at nutrient-replete conditions and following periods of nitrogen or phosphorous deprivation. Overall, smaller cells showed slower growth, lower storage capacity and poorer recovery from phosphorous depletion, as predicted by the ‘fasting endurance hypothesis'. However, recovery from nitrogen limitation was independent of size—a finding unanticipated by current theories. Phytoplankton species are responsible for much of the global carbon fixation and projected trends of cell size decline could reduce primary productivity by lowering the ability of a cell to store resources. [ABSTRACT FROM AUTHOR]

Summary: Cell size correlates with most traits among phytoplankton species. Theory predicts that larger cells should show poorer photosynthetic performance, perhaps due to reduced intracellular self‐shading (i.e. package effect). Yet current theory relies heavily on interspecific correlational approaches and causal relationships between size and photosynthetic machinery have remained untested. As a more direct test, we applied 250 generations of artificial selection (c. 20 months) to evolve the green microalga Dunaliella teriolecta (Chlorophyta) toward different mean cell sizes, while monitoring all major photosynthetic parameters. Evolving larger sizes (> 1500% difference in volume) resulted in reduced oxygen production per chlorophyll molecule – as predicted by the package effect. However, large‐evolved cells showed substantially higher rates of oxygen production – a finding unanticipated by current theory. In addition, volume‐specific photosynthetic pigments increased with size (Chla+b), while photo‐protectant pigments decreased (β‐carotene). Finally, larger cells displayed higher growth performances and Fv/Fm, steeper slopes of rapid light curves (α) and smaller light‐harvesting antennae (σPSII) with higher connectivity (ρ). Overall, evolving a common ancestor into different sizes showed that the photosynthetic characteristics of a species coevolves with cell volume. Moreover, our experiment revealed a trade‐off between chlorophyll‐specific (decreasing with size) and volume‐specific (increasing with size) oxygen production in a cell. [ABSTRACT FROM AUTHOR]

A major goal of evolutionary biology is to understand how beneficial mutations translate into increased fitness. Here, we study beneficial mutations that arise in experimental populations of yeast evolved in glucose-rich media. We find that fitness increases are caused by enhanced maximum growth rate (R) that come at the cost of reduced yield (K). We show that for some of these mutants, high R coincides with higher rates of ethanol secretion, suggesting that higher growth rates are due to an increased preference to utilize glucose through the fermentation pathway, instead of respiration. We examine the performance of mutants across gradients of glucose and nitrogen concentrations and show that the preference for fermentation over respiration is influenced by the availability of glucose and nitrogen. Overall, our data show that selection for high growth rates can lead to an enhanced Crabtree phenotype by the way of beneficial mutations that permit aerobic fermentation at a greater range of glucose concentrations. [ABSTRACT FROM AUTHOR]

Size imposes physiological and ecological constraints upon all organisms. Theory abounds on how energy flux covaries with body size, yet causal links are often elusive. As a more direct way to assess the role of size, we used artificial selection to evolve the phytoplankton species Dunaliella tertiolecta towards smaller and larger body sizes. Within 100 generations ( c. 1 year), we generated a fourfold difference in cell volume among selected lineages. Large-selected populations produced four times the energy than small-selected populations of equivalent total biovolume, but at the cost of much higher volume-specific respiration. These differences in energy utilisation between large (more productive) and small (more energy-efficient) individuals were used to successfully predict ecological performance ( r and K) across novel resource regimes. We show that body size determines the performance of a species by mediating its net energy flux, with worrying implications for current trends in size reduction and for global carbon cycles. [ABSTRACT FROM AUTHOR]

Many studies examine how body size mediates energy use, but few investigate how size simultaneously regulates energy acquisition. Furthermore, rarely energy fluxes are examined while accounting for the role of biotic and abiotic factors in which they are nested. These limitations contribute to an incomplete understanding of how size affects the transfer of energy through individuals, populations, and communities. Here we characterized photosynthesis-irradiance (P-I) curves and per-cell net-energy use for 21 phytoplankton species spanning across four orders of magnitude of size and seven phyla, each measured across six light intensities and four population densities. We then used phylogenetic mixed models to quantify how body size influences the energy turnover rates of a species, and how this changes across environments. Rate-parameters for the P-I curve and net-energy budgets were mostly highly correlated and consistent with an allometric size-scaling exponent of <1. The energy flux of a cell decreased with population density and increased with light intensity, but the effect of body size remained constant across all combinations of treatment levels (i.e. no [ABSTRACT FROM AUTHOR]

The triode operation of humidified PEM fuel cells has been investigated both with pure H 2 and with CO poisoned H 2 feed over commercial Vulcan supported Pt(30%)-Ru(15%) anodes. It was found that triode operation, which involves the use of a third, auxiliary, electrode, leads to up to 400% power output increase with the same CO poisoned H 2 gas feed. At low current densities, the power increase is accompanied by an increase in overall thermodynamic efficiency. A mathematical model, based on Kirchhoff’s laws, has been developed which is in reasonably good agreement with the experimental results. In order to gain some additional insight into the mechanism of triode operation, the model has been also extended to describe the potential distribution inside the Nafion membrane via the numerical solution of the Nernst-Planck equation. Both model and experiment have shown the critical role of minimizing the auxiliary-anode or auxiliary-cathode resistance, and this has led to improved comb-shaped anode or cathode electrode geometries. [ABSTRACT FROM AUTHOR]

Blue carbon ecosystems (BCE) include mangrove forests, tidal marshes, and seagrass meadows, all of which are currently under threat, putting their contribution to mitigating climate change at risk. Although certain challenges and trade-offs exist, remote sensing offers a promising avenue for transparent, replicable, and cost-effective accounting of many BCE at unprecedented temporal and spatial scales. The United Nations Framework Convention on Climate Change (UNFCCC) has issued guidelines for developing blue carbon inventories to incorporate into Nationally Determined Contributions (NDCs). Yet, there is little guidance on remote sensing techniques for monitoring, reporting, and verifying blue carbon assets. This review constructs a unified roadmap for applying remote sensing technologies to develop cost-effective carbon inventories for BCE – from local to global scales. We summarise and discuss (1) current standard guidelines for blue carbon inventories; (2) traditional and cutting-edge remote sensing technologies for mapping blue carbon habitats; (3) methods for translating habitat maps into carbon estimates; and (4) a decision tree to assist users in determining the most suitable approach depending on their areas of interest, budget, and required accuracy of blue carbon assessment. We designed this work to support UNFCCC-approved IPCC guidelines with specific recommendations on remote sensing techniques for GHG inventories. Overall, remote sensing technologies are robust and cost-effective tools for monitoring, reporting, and verifying blue carbon assets and projects. Increased appreciation of these techniques can promote a technological shift towards greater policy and industry uptake, enhancing the scalability of blue carbon as a Natural Climate Solution worldwide. • Blue carbon ecosystems (BCE) play a key role in climate change mitigation. • Remote sensing techniques are cost-effective for monitoring BCE extent and carbon stocks. • A tradeoff exists between spatial resolution and historical coverage of remotely sensed data. • New technologies can facilitate the inclusion of BCE in national inventories and Nationally Determined Contributions (NDCs). • Our decision tree guides the choice of remote sensing methods for monitoring BCE. [ABSTRACT FROM AUTHOR]

Trait-based approaches are increasingly used to help understanding community structure and ecosystem functioning. A large proportion of trait-based studies define a species by its mean trait values and assume intraspecific trait variability to be negligible compared to interspecific differences. However, this assumption is rarely tested., Phenotypic cell size plasticity can be particularly important in phytoplankton species, which are known for their rapid changes in cell size in response to variations in environmental conditions. While phytoplankton traits show clear systematic trends with mean cell size across species, how size-related plasticity influences the dynamics of a species remains unknown., In this study, we evaluate the effects of cell size plasticity on the nitrogen (N) utilization traits of the green alga Desmodesmus armatus (Chlorophyta), reared in different inorganic nitrogen sources (nitrate, ammonium or both) and nutrient histories (N-replete and N-deplete)., Results show that traits for per-cell ammonium uptake, maximum cell growth rate and minimum N-quota change substantially within the study species, depending on mean cell size and nutrient history. In contrast, per-cell nitrate uptake was independent of cell size. These results indicate that representing phytoplankton species only by their mean trait values could underestimate the physiological performance of a species by as much as one order of magnitude., This study highlights the extent to which explicit incorporation of within-species trait variability can enhance our understanding of how species performance changes along environmental gradients., A is available for this article. [ABSTRACT FROM AUTHOR]

Ecologists have often used indirect proxies to represent variables that are difficult or impossible to measure directly. In phytoplankton, the internal concentration of the most limiting nutrient in a cell determines its growth rate. However, directly measuring the concentration of nutrients within cells is inaccurate, expensive, destructive, and time-consuming, substantially impairing our ability to model growth rates in nutrient-limited phytoplankton populations. The red chlorophyll autofluorescence (hereafter “red fluorescence”) signal emitted by a cell is highly correlated with nitrogen quota in nitrogen-limited phytoplankton species. The aim of this study was to evaluate the reliability of including flow cytometric red fluorescence as a proxy for internal nitrogen status to model phytoplankton growth rates. To this end, we used the classic Quota model and designed three approaches to calibrate its model parameters to data: where empirical observations on cell internal nitrogen quota were used to fit the model (“Nitrogen-Quota approach”), where quota dynamics were inferred only from changes in medium nutrient depletion and population density (“Virtual-Quota approach”), or where red fluorescence emission of a cell was used as an indirect proxy for its internal nitrogen quota (“Fluorescence-Quota approach”). Two separate analyses were carried out. In the first analysis, stochastic model simulations were parameterized from published empirical relationships and used to generate dynamics of phytoplankton communities reared under nitrogen-limited conditions. Quota models were fitted to the dynamics of each simulated species with the three different approaches and the performance of each model was compared. In the second analysis, we fit Quota models to laboratory time-series and we calculate the ability of each calibration approach to describe the observed trajectories of internal nitrogen quota in the culture. Results from both analyses concluded that the Fluorescence-Quota approach including per-cell red fluorescence as a proxy of internal nitrogen substantially improved the ability of Quota models to describe phytoplankton dynamics, while still accounting for the biologically important process of cell nitrogen storage. More broadly, many population models in ecology implicitly recognize the importance of accounting for storage mechanisms to describe the dynamics of individual organisms. Hence, the approach documented here with phytoplankton dynamics may also be useful for evaluating the potential of indirect proxies in other ecological systems. [ABSTRACT FROM AUTHOR]

Nitrate and ammonium are the two most important ionic forms of inorganic nitrogen driving biomass production in marine and freshwater aquatic systems. The performance of plants and algae often changes when reared with either of these two forms of nitrogen individually, as well as when they are both present, or when cells have experienced previous periods of nitrogen starvation. Current functional responses quantifying how ambient nitrogen drives changes in population density are unable to capture interacting and transient effects of nitrate and ammonium. Hence, in this paper we formulate, calibrate, and test a new nitrate–ammonium quota model that accounts for nitrate and ammonium uptake, as well as the effects of nitrogen starvation length and ammonium-induced nitrate uptake inhibition. We fit the model with several time-series from the green alga Chlorella sp. reared in laboratory batch cultures under multiple initial conditions. We show that a single set of calibrated model parameters can capture time-series collected from experiments inoculated at 12 different initial concentrations of nitrate, ammonium, and biomass. The model also performed well when validated against time-series from two novel initial conditions withheld from model calibration. Our model therefore provides a framework for evaluating the potential broader ecological and environmental consequences of ambient nitrate and ammonium regimes for phytoplankton communities in nature and aquaculture. [ABSTRACT FROM AUTHOR]

Seagrass meadows are marine habitats with high ecological importance. Their detection in the fossil record will contribute to our understanding of the development of patterns of marine biodiversity through time and the response of coastal marine habitats to environmental change. Due to the low probability of fossilization of seagrass macrofossils, the reliable identification of seagrass meadows in the fossil record is often challenging. A wide range of indirect indicators has been applied to infer paleo-seagrass habitats in Late Cretaceous and Cenozoic deposits. The usefulness of those indicators is determined by various factors, such as their stratigraphic range, fossilization potential, habitat restriction, and others. Although they have sometimes been briefly summarized in the literature, a comprehensive review of indirect paleo-seagrass indicators, including an assessment of their value for recognition of this habitat, is not yet available. We summarize them here and explore their usefulness. We aim to assist future workers to identify facies and fossil assemblages associated with seagrass beds. Apart from a few truly diagnostic proxies, combinations of several indicators turn out to be most reliable when aiming to identify the presence of paleo-seagrass habitats. The presence/absence of many potentially seagrass-associated taxa cannot serve as a useful indicator due to a lack of habitat restriction, but statistical evaluations of abundance data are promising to discriminate seagrass beds from neighboring areas. However, such studies are available for only a few commonly seagrass-associated organism groups. Furthermore, the applicability of many indicators is confined by latitude, because their occurrence is restricted to (sub)tropical or at most warm temperate regions. [ABSTRACT FROM AUTHOR]

A multi-nutrient quota model was modified to describe the coupled dynamics of nitrate and nitrite utilization for four phytoplankton species, Picochlorum atomus (Butcher) (Chlorophyta), Nannochloropsis oculata (Droop) (Ochrophyta), Isochrysis sp. (Haptophyta), and Pyrocystis lunula (Schütt) (Dinophyta). Although rarely considered in nutrient-limited phytoplankton models, nitrite can be an important nitrogen source, as it can be either released due to incomplete reduction of nitrate or taken up to supplement low nitrogen availability. The model accurately characterizes the dynamics of nitrite uptake and excretion, nitrate uptake and assimilation efficiency, and population growth for the study species in batch culture, despite the fact that the species display a range of qualitatively different nutrient utilization patterns. The good performance of the model suggests that per-capita secretion and re-assimilation of nitrite, together with changes to the per-capita internal nitrogen supply, can be inferred from daily observations of medium nitrate and nitrite utilization and population growth. The model also reproduces qualitative characteristics of nitrite dynamics that have been observed in previous empirical studies, such as a rise in per-capita nitrite secretion when culture medium nitrate concentrations and intracellular nitrogen levels are high. Our model therefore provides a new framework for evaluating the potential broader trophic consequences of the effects of nitrite uptake and release on the dynamics of phytoplankton populations. [ABSTRACT FROM AUTHOR]

Although activating mutations of fibroblast growth factor receptor 3 (FGFR3) are frequent in bladder tumors, little information is available on their specific effects in urothelial cells or the basis for the observed mutation spectrum. We investigated the phenotypic and signaling consequences of three FGFR3 mutations (S249C, Y375C, and K652E) in immortalized normal human urothelial cells (TERT-NHUC) and mouse fibroblasts (NIH-3T3). In TERT-NHUC, all mutant forms of FGFR3 induced phosphorylation of FRS2α and ERK1/2, but not AKT or SRC. PLCγ1 phosphorylation was only observed in TERT-NHUC expressing the common S249C and Y375C mutations, and not the rare K652E mutation. Cells expressing S249C and Y375C FGFR3 displayed an increased saturation density, related to increased proliferation and viability. This effect was significantly dependent on PLCγ1 signaling and undetectable in cells expressing K652E FGFR3, which failed to phosphorylate PLCγ1. In contrast to TERT-NHUC, expression of mutant FGFR3 in NIH-3T3 resulted in phosphorylation of Src and Akt. In addition, all forms of mutant FGFR3 were able to phosphorylate Plcγ1 and induce morphological transformation, cell proliferation, and anchorage-independent growth. Our results indicate that the effects of mutant FGFR3 are both cell type specific and mutation specific. Mutant FGFR3 may confer a selective advantage in the urothelium by overcoming normal contact inhibition of proliferation. [ABSTRACT FROM AUTHOR]

Dys-regulation of the insulin-like growth factor (IGF) system increases the risk of a number of malignancies. The aim of this study was to investigate the role of members of the IGF binding protein (IGFBP) superfamily in the development of oesophageal adenocarcinoma (EAC) and their possible use as markers of disease risk. Expression of IGFBP-2, IGFBP-3, IGFBP-4, and IGFBP-10/CYR61 was assessed using Real-Time-polymerase chain reaction (PCR) and immunohistochemistry in oesophageal tissues from Barrett's oesophagus (BE) patients with and without associated EAC, and in control subjects. IGFBP-3, IGFBP-4, and IGFBP-10/CYR61 mRNA levels were up-regulated in Barrett's (n=17) and tumour tissue of EAC patients (n=18) compared with normal tissue of control subjects without BE or EAC (n=18) (p

[Display omitted] • New sequences from 199 cheilostome bryozoan colonies (165 species) are presented. • A broadly resolved 17 gene (2 nucl and 15 mt) and 267 taxa phylogeny is shown. • The phylogeny shows higher-level cheilostome systematics are in need of revision. • Frontal-shields have evolved multiple times independently, but never lost. • A molecular framework is provided to test additional evolutionary hypotheses. Larger molecular phylogenies based on ever more genes are becoming commonplace with the advent of cheaper and more streamlined sequencing and bioinformatics pipelines. However, many groups of inconspicuous but no less evolutionarily or ecologically important marine invertebrates are still neglected in the quest for understanding species- and higher-level phylogenetic relationships. Here, we alleviate this issue by presenting the molecular sequences of 165 cheilostome bryozoan species from New Zealand waters. New Zealand is our geographic region of choice as its cheilostome fauna is taxonomically, functionally and ecologically diverse, and better characterized than many other such faunas in the world. Using this most taxonomically broadly-sampled and statistically-supported cheilostome phylogeny comprising 214 species, when including previously published sequences, and 17 genes (2 nuclear and 15 mitochondrial) we tested several existing systematic hypotheses based solely on morphological observations. We find that lower taxonomic level hypotheses (species and genera) are robust while our inferred trees did not reflect current higher-level systematics (family and above), illustrating a general need for the rethinking of current hypotheses. To illustrate the utility of our new phylogeny, we reconstruct the evolutionary history of frontal shields (i.e., a calcified body-wall layer in ascus-bearing cheilostomes) and ask if its presence has any bearing on the diversification rates of cheilostomes. [ABSTRACT FROM AUTHOR]

Farm dams are a ubiquitous limnological feature of agricultural landscapes worldwide. While their primary function is to capture and store water, they also have disproportionally large effects on biodiversity and biogeochemical cycling, with important relevance to several Sustainable Development Goals (SDGs). However, the abundance and distribution of farm dams is unknown in most parts of the world. Therefore, we used artificial intelligence and remote sensing data to address this critical global information gap. Specifically, we trained a deep learning convolutional neural network (CNN) on high-definition satellite images to detect farm dams and carry out the first continental-scale assessment on density, distribution and historical trends. We found that in Australia there are 1.765 million farm dams that occupy an area larger than Rhode Island (4678 km2) and store over 20 times more water than Sydney Harbour (10,990 GL). The State of New South Wales recorded the highest number of farm dams (654,983; 37% of the total) and Victoria the highest overall density (1.73 dams km−2). We also estimated that 202,119 farm dams (11.5%) remain omitted from any maps, especially in South Australia, Western Australia and the Northern Territory. Three decades of historical records revealed an ongoing decrease in the construction rate of farm dams, from >3% per annum before 2000, to ~1% after 2000, to <0.05% after 2010—except in the Australian Capital Territory where rates have remained relatively high. We also found systematic trends in construction design: farm dams built in 2015 are on average 50% larger in surface area and contain 66% more water than those built in 1989. To facilitate sharing information on sustainable farm dam management with authorities, scientists, managers and local communities, we developed AusDams.org—a free interactive portal to visualise and generate statistics on the physical, environmental and ecological impacts of farm dams. [ABSTRACT FROM AUTHOR]

Abstract: Traumatic neuromas (TN) of the biliary tree causing strictures have only occasionally been described after liver transplantation. Herein, we have reported 15 cases of TN that were detected between 1 and 17 months after transplantation (median: 4 months) during surgery for obstructive jaundice (12 cases), after alterations of liver function tests (two cases), or incidentally discovered after retransplantation (n = 1) we resected the lesion and the biliary anastomosis. Pathological examination and immunostaining for S-100 protein were performed to study the nerve fascicles. After a median follow-up time of 64 months (range = 0–127), 10 patients are alive without any complication related to the previous biliary TN. We propose the following classification: type I: TN originating from and located in the main biliary tract wall, and type II: TN arising from the surrounding tissues next to the main biliary tract. We conclude that TN are not uncommon after liver transplantation and that they are sometimes symptomatic, causing a biliary stricture that requires surgical treatment. We propose a classification to help patient selection for surgery. In our opinion, resection of the TN is the operation of choice, together with resection of the involved biliary tract in type I TN. [Copyright &y& Elsevier]

Genome size is tightly coupled to morphology, ecology, and evolution among species [ 1–5 ], with one of the best-known patterns being the relationship between cell size and genome size [ 6 , 7 ]. Classic theories, such as the "selfish DNA hypothesis," posit that accumulating redundant DNA has fitness costs but that larger cells can tolerate larger genomes, leading to a positive relationship between cell size and genome size [ 8 , 9 ]. Yet the evidence for fitness costs associated with relatively larger genomes remains circumstantial. Here, we estimated the relationships between genome size, cell size, energy fluxes, and fitness across 72 independent lineages in a eukaryotic phytoplankton. Lineages with relatively smaller genomes had higher fitness, in terms of both maximum growth rate and total biovolume reached at carrying capacity, but paradoxically, they also had lower energy fluxes than lineages with relative larger genomes. We then explored the evolutionary trajectories of absolute genome size over 100 generations and across a 10-fold change in cell size. Despite consistent directional selection across all lineages, genome size decreased by 11% in lineages with absolutely larger genomes but showed little evolution in lineages with absolutely smaller genomes, implying a lower absolute limit in genome size. Our results suggest that the positive relationship between cell size and genome size in nature may be the product of conflicting evolutionary pressures, on the one hand, to minimize redundant DNA and maximize performance—as theory predicts—but also to maintain a minimum level of essential function. • Cells evolving relatively less genome for their size have higher fitness • Adaptive evolution tends to minimize genome size relative to cell size • An absolute lower limit for the evolution of smaller genome exists in this species • We found a delayed response of genome size to the evolution of cell size By using evolved lineages of the same eukaryotic species, Malerba et al. provide evidence for fitness benefits associated with reducing relative genome size and DNA content within a cell—as predicted by the selfish DNA hypothesis. We also see indications of countervailing forces imposing a minimum genome size in this species. [ABSTRACT FROM AUTHOR]

Zirconium pentatelluride was recently reported to be a 3D Dirac semimetal, with a single conical band, located at the center of the Brillouin zone. The cone's lack of protection by the lattice symmetry immediately sparked vast discussions about the size and topological or trivial nature of a possible gap opening. Here, we report on a combined optical and transport study of ZrTe5, which reveals an alternative view of electronic bands in this material. We conclude that the dispersion is approximately linear only in the a-c plane, while remaining relatively flat and parabolic in the third direction (along the b axis). Therefore, the electronic states in ZrTe5 cannot be described using the model of 3D Dirac massless electrons, even when staying at energies well above the band gap 2Δ=6 meV found in our experiments at low temperatures. [ABSTRACT FROM AUTHOR]

Exercise countermeasures are the main approach taken to protect astronauts from musculoskeletal deconditioning in microgravity (μg). Future exploration class missions will require astronauts to live on the surface of the Moon (0.16g) and Mars (0.38g) in hypogravity where the level of protection is assumed to be insufficient. However, it is not well understood how much exercise is required to protect the musculoskeletal system against 'small planet deconditioning'. The purpose of this review was to systematically synthesize evidence regarding the effectiveness of exercise countermeasures for the prevention of musculoskeletal deconditioning in hypogravity. Databases were searched for relevant literature using appropriate search terms: PubMed, Web of Science, EMBASE, The Cochrane Collaboration Library, SPORTDiscus, the National Aeronautics and Space Administration (NASA) Technical Reports Sever, the NASA Life Science Data Archive and the German Aerospace Centre Elibrary. Two independent reviewers screened hits for relevance in accordance with the a priori PICOS criteria. Studies that included Earth based hypogravity analogs (e.g. head up tilt bed rest), a healthy terrestrial population, an exercise countermeasure and non exercise control group (i.e. randomized/clinical control trial), measuring any musculoskeletal outcome, were eligible for inclusion. Space related research (e.g. Lunar mission data) were not eligible for inclusion. No studies were identified that met the eligibility criteria established for this review. Of the n = 2805 articles identified, n = 124 were classified as potentially relevant, however all were excluded following full text examination. Assumptions regarding the effect of hypogravity on the human musculoskeletal system are yet to be confirmed with long duration data. Future research should aim to fill this gap by investigating the longitudinal effects of simulated hypogravity (and Lunar/Martian habitat environments) on the human musculoskeletal system, to establish whether any deconditioning is of a large enough magnitude to compromise health and performance. If so, thereafter investigating exercise countermeasure strategies to prevent deconditioning in simulated Lunar/Martian settings will help inform evidence-based medical guidelines for planetary exploration. The ecological validity and thus transferability of data from chronic hypogravity analogs are essential to providing accurate and high quality data. Therefore, Lunar/Martian data is extremely valuable to understand whether data collected in analogs can be accurately transferred. • Review of exercise to prevent musculoskeletal deconditioning in hypogravity. • Zero studies met the eligibility criteria. • Long duration animal and human research is required in simulated hypogravity. [ABSTRACT FROM AUTHOR]

Ruxolitinib is beneficial in patients with myelofibrosis (MF) and polycythemia vera (PV). Information on ruxolitinib adherence is scant. The Ruxolitinib Adherence in Myelofibrosis and Polycythemia Vera (RAMP) prospective multicenter study (NCT06078319) included 189 ruxolitinib-treated patients. Patients completed the Adherence to Refills and Medications Scale (ARMS) and Distress Thermometer and Problem List (DTPL) at the earliest convenience, after registration in the study, and at later timepoints. At week-0, low adherence (ARMS > 14) and high distress (DT ≥ 4) were declared by 49.7% and 40.2% of patients, respectively. The main reason for low adherence was difficult ruxolitinib supply (49%), intentional (4.3%) and unintentional (46.7%) non-take. In multivariable regression analysis, low adherence was associated to male sex (p = 0.001), high distress (p < 0.001), and treatment duration ≥ 1 year (p = 0.03). Over time, rates of low adherence and high distress remained stable, but unintentional non-take decreased from 47.9% to 26.0% at week-48. MF patients with stable high adherence/low distress were more likely to obtain/maintain the spleen response at week-24. Low adherence to ruxolitinib represents an unmet clinical need that require a multifaceted approach, based on reason behind it (patients characteristics and treatment duration). Its recognition may help distinguishing patients who are truly refractory and those in need of therapy optimization. [ABSTRACT FROM AUTHOR]

According to many guidelines, scintigraphy remains the first suggested diagnostic procedure in hyperthyroid patients in spite of the widespread availability of ultrasounds. The aim of this study was to evaluate the cost-effectiveness of sonography versus scintigraphy in the management of Graves's disease, and to assess ultrasound features suggesting cancer in detecting thyroid nodules. Among 1470 hyperthyroid patients evaluated in our department from 2002 to 2005, 426 (29%) had Graves' disease: echographic and scintigraphic features were not suggestive of GD in 20/426 (4.8%) and 11/426 (2.6%) patients, respectively (p=0.763), even if one of the two procedures was almost always diagnostic. Ultrasound identified 68/426 (16%) patients with a concomitant solid lesion, while scintigraphy detected only 9/426 (2.1%) "cold" nodules (p<0.001). Thyroid cancer was diagnosed in 30/68 (47.7%) patients. Malignancy presented at ultrasound investigation blurred margins (26.7% versus 15.8%), microcalcifications (33.3% versus 28.9%) and an anteroposterior and transverse diameter ratio>or=1 (73.3% versus 71.1%); more frequently than benign nodules, but this was not statistically significant. The total cost to obtain a diagnosis by ultrasound was euro14645.34 (euro13312.5 for echography+euro1332.84 for scintigraphy in the 29 patients "negative" at echographic evaluation for GD) versus euro19922.71 by scintigraphy (euro19578.96 for scan+euro343.75 for ultrasounds in the 11 patients "negative" at scintigraphy). Our data show no difference in terms of diagnosis between sonography and scintigraphy. Indeed, scintigraphy was less sensitive in detecting nodules (often of malignant nature) than ultrasound, and, moreover, with a consequent increase of the direct cost of nodule management when scintigraphy is the first line procedure. In conclusion, according to our results, we suggest that ultrasounds with color-Doppler evaluation should be performed as first step in all hyperthyroid patients, and that scintigraphic examination should be limited only to the uncommon cases, where physician's observation, laboratory assays and/or ultrasounds are not diagnostic. [ABSTRACT FROM AUTHOR]

Examines the effects of amiodarone on circulating antithyroid antibodies. Development of hypothyroidism while receiving amiodarone; High prevalence of antimicrosomal antibodies; Increases serum concentrations of thyroid stimulating hormone.

Artificial water bodies in agricultural landscapes (hereafter 'farm dams') are established primarily to support livestock and crop production but also provide habitats for a wide range of native species. Managing water quality in farm dams is essential to animal production and biodiversity. Farm dam enhancement, which includes restricting direct access of stock to dams, can improve water quality in farm dams, by reducing soil erosion and direct faecal contamination, as well as reducing the trampling, grazing, and browsing of vegetation in the immediate catchment. We tested farm dam enhancement as a tool to improve and maintain water quality in 109 farm dams across 34 farms over three years in the sheep-wheat belt of southeast Australia. Using Bayesian Linear Mixed Models, we found that farm dam enhancement significantly reduced levels of phosphorus, nitrogen, turbidity, thermotolerant coliforms, Escherichia coli , and pH. Furthermore, our study revealed links between dam enhancement, increases in vegetation cover, and improved water quality. Our results show that restoration efforts in the surrounds of dams can have positive results on water quality. They highlight the importance of restoration in agricultural landscapes to both agricultural production and biodiversity. • Managing water quality in farms dams is essential to production and biodiversity. • Dams can be enhanced by restoring vegetation and reducing direct stock access. • Dam enhancement significantly reduced levels of phosphorus and nitrogen. • It also reduced turbidity, thermotolerant coliforms, and Escherichia coli. [ABSTRACT FROM AUTHOR]

Abstract: According to many guidelines, scintigraphy remains the first suggested diagnostic procedure in hyperthyroid patients in spite of the widespread availability of ultrasounds. The aim of this study was to evaluate the cost-effectiveness of sonography versus scintigraphy in the management of Graves''s disease, and to assess ultrasound features suggesting cancer in detecting thyroid nodules. Among 1470 hyperthyroid patients evaluated in our department from 2002 to 2005, 426 (29%) had Graves’ disease: echographic and scintigraphic features were not suggestive of GD in 20/426 (4.8%) and 11/426 (2.6%) patients, respectively (p =0.763), even if one of the two procedures was almost always diagnostic. Ultrasound identified 68/426 (16%) patients with a concomitant solid lesion, while scintigraphy detected only 9/426 (2.1%) “cold” nodules (p <0.001). Thyroid cancer was diagnosed in 30/68 (47.7%) patients. Malignancy presented at ultrasound investigation blurred margins (26.7% versus 15.8%), microcalcifications (33.3% versus 28.9%) and an anteroposterior and transverse diameter ratio ≥1 (73.3% versus 71.1%); more frequently than benign nodules, but this was not statistically significant. The total cost to obtain a diagnosis by ultrasound was €14645.34 (€13312.5 for echography+€1332.84 for scintigraphy in the 29 patients “negative” at echographic evaluation for GD) versus €19922.71 by scintigraphy (€19578.96 for scan+€343.75 for ultrasounds in the 11 patients “negative” at scintigraphy). Our data show no difference in terms of diagnosis between sonography and scintigraphy. Indeed, scintigraphy was less sensitive in detecting nodules (often of malignant nature) than ultrasound, and, moreover, with a consequent increase of the direct cost of nodule management when scintigraphy is the first line procedure. In conclusion, according to our results, we suggest that ultrasounds with color-Doppler evaluation should be performed as first step in all hyperthyroid patients, and that scintigraphic examination should be limited only to the uncommon cases, where physician''s observation, laboratory assays and/or ultrasounds are not diagnostic. [Copyright &y& Elsevier]

Two chitin synthase ( Chs ) genes (class II and class IV, respectively) were identified in the mycelium of strain PSIV, a sterile ascomycete capable of establishing ericoid mycorrhiza. Both genes were constitutively expressed during mycelial growth in liquid medium. However, when the fungus was challenged with toxic amounts of zinc ions, the accumulation of class II, but not class IV, Chs mRNAs was inhibited. To our knowledge, this is the first report on the differential expression of distinct Chs mRNAs following exposure to heavy metals. [ABSTRACT FROM AUTHOR]

Summary: Several studies have suggested a link between human microbiome and rheumatoid arthritis (RA) development. Porphyromonas gingivalis seems involved in RA initiation and progression, as supported by the high occurrence of periodontitis. In this case–control study, we analysed tongue P. gingivalis presence and quantification in a large healthy and RA cohort. We enrolled 143 RA patients [male/female (M/F) 32/111, mean ± standard deviation (s.d.), age 57·5 ± 19·8 years, mean ± s.d. disease duration 155·9 ± 114·7 months); 36 periodontitis patients (M/F 11/25, mean ± s.d., age 56 ± 9·9 years, mean ± s.d. disease duration 25·5 ± 20·9 months); and 57 patients (M/F 12/45, mean ± s.d., age 61·4 ± 10·9 years, mean ± s.d. disease duration 62·3 ± 66·9 months) with knee osteoarthritis or fibromyalgia. All subjects underwent a standard cytological swab to identify the rate of P. gingivalis/total bacteria by using quantitative real‐time polymerase chain reaction. The prevalence of P. gingivalis resulted similarly in RA and periodontitis patients (48·9 versus 52·7%, P = not significant). Moreover, the prevalence of this pathogen was significantly higher in RA and periodontitis patients in comparison with control subjects (P = 0·01 and P = 0·003, respectively). We found a significant correlation between P. gingivalis rate in total bacteria genomes and disease activity score in 28 joints (DAS28) (erythrocyte sedimentation rate) (r = 0·4, P = 0·01). RA patients in remission showed a significantly lower prevalence of P. gingivalis in comparison with non‐remission (P = 0·02). We demonstrated a significant association between the percentage of P. gingivalis on the total tongue biofilm and RA disease activity (DAS28), suggesting that the oral cavity microbiological status could play a role in the pathogenic mechanisms of inflammation, leading to more active disease. ‐Significant correlation between P. gingivalis rate in total bacteria genomes and disease activity in terms of DAS28 values and remission status. ‐Oral cavity microbiological status could play a role in the pathogenic mechanisms of inflammation, leading to a more active disease. ‐Beyond citrullination and antibody production, P. gingivalis could be implicated in triggering a pro‐inflammatory state in rheumatoid arthritis. [ABSTRACT FROM AUTHOR]

Dopamine agonists are considered as the first line therapy in prolactin (PRL) secreting pituitary adenomas inducing a normalization of serum PRL and reduction of tumor size. It is known that serum PRL levels, obtained during treatment, are a predictor of tumor shrinkage. Whether PRL suppression below the lower limit of the normal range is related to a greater chance of tumor shrinkage than just its normalization has not been established. This retrospective cohort study was carried out in a tertiary center. Clinical records of 151 patients with PRL-secreting pituitary adenomas (73 micro-, 78 macroadenomas) treated with cabergoline for at least 24 months were analyzed. The adenoma size was analyzed by MRI before and after 24 months of treatment. PRL levels were evaluated every 6 months, assigning a score at each time point (PRL 0 = suppressed; 1 = normal; 2 = above normal). The total score, after 24 months of treatment, was expressed as the sum of the score at each time point and ranged between 0 and 8. A tumor shrinkage was observed in 102/151 patients (67.5 %) and it was significantly associated to a lower PRL total score (p = 0.021, OR = 0.85, CI = 0.73-0.97), being significantly more frequent in patients with suppressed PRL than in those with normal PRL (p = 0.045, OR = 0.42, CI = 0.18- 0.98) at 24 months. Cabergoline therapy with the goal of achieving PRL levels below the lower limit of normal range can increase the chance to obtain tumor shrinkage of PRL-secreting pituitary adenomas. [ABSTRACT FROM AUTHOR]

Mycorrhizal fungi are key mediators of soil-to-plant movement of mineral nutrients, including essential and non-essential metals. In soil conditions that facilitate mobilization of metal ions, potentially toxic metals can interfere with nitrogen metabolism in both plants and microorganisms. Less is known about possible relationships between nitrogen metabolism and responses to heavy metals. Aim of this study was to investigate this aspect in the ericoid mycorrhizal fungus Oidiodendron maius strain Zn, a metal tolerant ascomycete. Growth of O. maius Zn on zinc and cadmium containing media was significantly affected by the nitrogen source. Screening of a library of O. maius Zn random genetic transformants for sensitivity to heavy metals (zinc and cadmium) and oxidative stress (menadione) yielded a mutant strain that carried a partial deletion of the glutamate synthase (NADH-GOGAT EC 1.4.1.14) gene and its adjacent gene, the APC15 subunit of the anaphase promoting complex. Comparison of WT and OmGOGAT-OmAPC15 mutant strains indicated an impaired N-metabolism and altered stress tolerance, and assays on the OmAPC15 -recomplemented strains ascribed the observed phenotypes to the deletion in the OmGOGAT gene. OmGOGAT disruption modified the nitrogen pathway, with a strong reduction of the associated glutamine synthetase (GS, EC 6.3.1.2) activity and an up-regulation of the alternative NADP-glutamate dehydrogenase (NADP-GDH, EC 1.4.1.4) pathway for glutamate biosynthesis. Unless they were supplemented with glutamine, O. maius Zn transformants lacking OmGOGAT were very sensitive to zinc. These results highlight the importance of nitrogen metabolism not only for nitrogen assimilation and transformation, but also for stress tolerance. For mycorrhizal fungi, such as O. maius , this may bear consequences not only to the fungus, but also to the host plant. [ABSTRACT FROM AUTHOR]

An aortic aneurysm is a permanent and localized dilatation of the aorta resulting from an irreversible loss of structural integrity of the aortic wall. The infrarenal segment of the abdominal aorta is the most common site of aneurysms; however, they are also common in the ascending and descending thoracic aorta. Many cases remain undetected because thoracic aortic aneurysms (TAAs) are usually asymptomatic until complications such as aortic dissection or rupture occurs. Clinical estimates of rupture potential and dissection risk, and thus interventional planning for TAAs, are currently based primarily on the maximum diameter and growth rate. The growth rate is calculated from maximum diameter measurements at two subsequent time points; however, this measure cannot reflect the complex changes of vessel wall morphology and local areas of weakening that underline the strong regional heterogeneity of TAA. Due to the high risks associated with both open and endovascular repair, an intervention is only justified if the risk for aortic rupture or dissection exceeds the interventional risks. Consequently, TAAs clinical management remains a challenge, and new methods are needed to better identify patients for elective repair. We reviewed the pathophysiology of TAAs and the role of mechanical stresses and mathematical growth models in TAA management; as a proof of concept, we applied a multiscale biomechanical analysis to a case study of TAA. [ABSTRACT FROM AUTHOR]

Objective: Abnormalities of glucose metabolism are common findings of acromegaly. However, robust evidence on whether therapy with somatostatin analogs (SSAs) or pegvisomant (PEG) differently affects glucose metabolism is lacking. The purpose of this study was to evaluate the effects of therapy with SSAs, PEG, or their combination on glucose metabolism in a large series of acromegalic patients. Design: This was a historical-prospective study. Among 50 consecutive acromegalic patients under SSA therapy, acromegaly in 19 patients was controlled. PEG used in combination with SSA therapy allowed the control of acromegaly in the remaining 31 patients and was then continued as monotherapy in 18 patients. Methods: The following parameters were evaluated at the diagnosis of acromegaly and during different treatments: fasting plasma glucose (FPG) and insulin concentrations, insulin sensitivity (QUICK-I), homeostasis model assessment of insulin resistance (HOMA2-IR), and plasma glucose and insulin concentrations during the oral glucose tolerance test (OGTT). Comparison was made using analysis for paired data. Results: Insulin resistance improved when acromegaly was controlled with therapy with SSAs, PEG, or SSA + PEG. However, FPG concentrations were higher during SSA therapy (alone or combined with PEG) than at the diagnosis of acromegaly, even when corrected for disease activity, whereas they were reduced during PEG therapy. Mean glucose concentrations during the OGTT were higher in patients receiving SSA therapy than in those receiving PEG therapy. In addition, the prevalence of diabetes or impaired glucose tolerance was higher during SSA therapy than at diagnosis or during PEG therapy and was not influenced by disease control. Conclusions: Medical therapies for acromegaly reduce insulin resistance and increase insulin sensitivity; on the contrary, glucose indexes may be differently affected by SSA or PEG therapy. [ABSTRACT FROM AUTHOR]