Assessing lignocellulosic biomass production from crop residues in the European Union: Modelling,analysis of the current scenario and drivers of interannual variability

This study assesses crop residues in the EU from major crops using empirical models to predict crop residues from yield statistics; furthermore it analyses the inter‐annual variability of those estimates over the period 1998‐2015, identifying its main drivers across Europe. The models were constructed based on an exhaustive collection of experimental data from scientific papers for the crops: wheat, barley, rye, oats, triticale, rice, maize, sorghum, rapeseed, sunflower, soybean, potato and sugarbeet. We discuss the assumptions on the relationship between yield and the harvest index, adopted by previous studies, to interpret the experimental data, quantify the uncertainties of these models, and establish the premises to implement them at regional scale –i.e., NUTS level 3– within the EU. To cope this, we created a consolidated sub‐national statistical data along with an algorithm able to aggregate (figures are provided at country level) and disaggregate (production at 25 km grid is provided assupplementary material) estimates. The total lignocellulosic biomass production in the EU28 over the review period, according to our models, is 419 Mt, from which wheat is the major contributor (155 Mt). Our results show that maize and rapeseed are the two crops with the highest residue yield, respectively 8.9 and 8.6 t ha‐1. The spatial analysis revealed that these three crops, which, according to our results, are feedstocks highly suitable a priori for second generation biofuels in the EU and are unevenly distributed across Europe. Weather fluctuation was identified as the major driver in residue production from cereals, while, in the case of starch crops and oilseeds – which are predominant in northern Europe – corresponded to the marked production trend likely influenced by the agricultural policies and agro‐management over the review period. Our results, among others, could help to understand and quantify the ecological boundaries of the bioeconomy from agriculture.     

Salivary calculi microbiota: new insights into microbial networks and pathogens reservoir

Sialolithiasis represents the most common disorders of salivary glands in middle-aged patients. It has been hypothesized that the retrograde migration of bacteria from the oral cavity to gland ducts may facilitate the formation of stones. Thus, in the present study, a microbiome characterization of salivary calculi was performed to evaluate the abundance and the potential correlations between microorganisms constituting the salivary calculi microbiota. Our data supported the presence of a core microbiota of sialoliths constituted principally by Streptococcus spp., Fusobacterium spp. and Eikenella spp., along with the presence of important pathogens commonly involved in infective sialoadenitis.     

National inventories of land occupation and transformation flows in the world for land use impact assessment

Purpose

Land use can cause significant impacts on ecosystems and natural resources. To assess these impacts using life cycle assessment (LCA) and ensure adequate decision-making, comprehensive national inventories of land occupation and transformation flows are required. Here, we aim at developing globally differentiated inventories of land use flows that can be used for primary use in life cycle impact assessment or national land planning.

Methods

Using publicly available data and inventory techniques, national inventories for several land use classes were developed. All land use classes were covered with the highest retrievable level of disaggregation within urban, forestry, agriculture and other land use classes, thus differentiating 21 land use classes. For illustrating the application of this newly developed inventory, two different application settings relevant to life cycle impact assessment were considered: the calculation of global normalisation references for 11 land use impact indicators related to soil quality assessment (adopting the methods recommended by the EU Commission) and the determination of generic globally applicable characterisation factors (CFs) resulting from aggregation of country-level CFs for situations for use when land use location is unknown.

Results and discussion

We built national inventories of 21 land occupation and 17 land transformation flows for 225 countries in the world for the reference year 2010. Cross-comparisons with existing inventories of narrower scopes attested its consistency. Detailed analyses of the calculated global normalisation references for the 11 land use impact categories showed different patterns across the land use impact indicators for each country, thus raising attention on key land use impacts specific to each country. Furthermore, the upscaling of country-level CFs to global generic CFs using the land use inventory revealed discrepancies with other alternative approaches using land use data at different resolutions.

Conclusions

In this study, we made a first attempt at developing national inventories of land use flows with sufficient disaggregation level to enable the calculation of normalisation references and differentiated impacts. However, the findings also demonstrated the need to refine the consistency of the inventory, particularly in the combination of land cover and land use data, which should be harmonised in future studies, and to expand it with differentiated coverage of more land use flows relevant to impact assessment.

     

A global review and meta-analysis of applications of the freshwater Fish Invasiveness Screening Kit

Reviews in Fish Biology and Fisheries - The freshwater Fish Invasiveness Screening Kit (FISK) has been applied in 35 risk assessment areas in 45 countries across the six inhabited continents (11...     

Maize seedlings produced from dry seeds exposed to liquid nitrogen display altered levels of shikimate pathway compounds

In light of climate change and risks of food insecurity, it is becoming increasingly important to preserve plant germplasm in genebanks. Storage of seeds, particularly via cryopreservation, is one of the most proficient methods for ex situ plant germplasm conservation. Whilst seed cryo-banking can have little, to no, or even beneficial effects on subsequent seedling vigor in some species, it can lead to a number of plant abnormalities (morphological and physiological). This study investigated the effects of maize seed cryopreservation on seedling growth (until 14 d) and levels of selected amino acids produced in the shikimate pathway, a major link between primary and secondary metabolism. Seed cryopreservation reduced FW in recovered seedlings, reduced caffeic acid (2.5-fold decrease), and increased levels of all other shikimate pathway–related compounds assessed: phenylalanine (2.9-fold increase), tyrosine (2.6-fold increase), and shikimic (2.1-fold increase) and protocathecuic (3.1-fold increase) acids in cotyledons. Our results suggest that maize seed cryopreservation results in seedlings that exhibit signs of an ‘overly’ efficient and caffeic acid–deficient shikimate pathway, possibly related to their reduced growth during a highly vulnerable growth stage. However, these metabolic abnormalities manifested most severely in the maternal (cotyledonary), as opposed to vegetative (roots, stems, and leaves), tissues and hence are likely to disappear when the seedlings shed the cotyledons and become completely autotrophic.

     

Changes in apoplastic peroxidase activity and cell wall composition are associated with cold‐induced morpho‐anatomical plasticity of wheat leaves

• Temperate grasses, such as wheat, become compact plants with small thick leaves after exposure to low temperature. These responses are associated with cold hardiness, but their underlying mechanisms remain largely unknown. Here we analyse the effects of low temperature on leaf morpho‐anatomical structure, cell wall composition and activity of extracellular peroxidases, which play key roles in cell elongation and cell wall thickening, in two wheat cultivars with contrasting cold‐hardening ability.
• A combined microscopy and biochemical approach was applied to study actively growing leaves of winter (ProINTA‐Pincén) and spring (Buck‐Patacón) wheat developed under constant warm (25 °C) or cool (5 °C) temperature.
• Cold‐grown plants had shorter leaves but longer inter‐stomatal epidermal cells than warm‐grown plants. They had thicker walls in metaxylem vessels and mestome sheath cells, paralleled with accumulation of wall components, predominantly hemicellulose. These effects were more pronounced in the winter cultivar (Pincén). Cold also induced a sharp decrease in apoplastic peroxidase activity within the leaf elongating zone of Pincén, and a three‐fold increase in the distal mature zone of the leaf. This was consistent with the enhanced cell length and thicker cell walls in this cultivar at 5 °C.
• The different response to low temperature of apoplastic peroxidase activity and hemicellulose between leaf zones and cultivar types suggests they might play a central role in the development of cold‐induced compact morphology and cold hardening. New insights are presented on the potential temperature‐driven role of peroxidases and hemicellulose in cell wall dynamics of grasses.

     

Nisin Production by Enterococcus hirae DF105Mi Isolated from Brazilian Goat Milk

The purpose of this study was to select the promising biopreservation bacteriocin producer strain from goat milk and characterize the expressed bacteriocin, related to its physiological and biochemical properties and specificity of operon encoding production and expression of antimicrobial peptide. Brazilian goat milk was used as the source for the selection of bacteriocin-producing lactic acid bacteria. One strain (DF105Mi) stood out for its strong activity against several Listeria monocytogenes strains. Selected strain was identified based on the biochemical and physiological characteristics and 16s rRNA analysis. The bacteriocin production and inhibitory spectrum of strain DF105Mi were studied, together with the evaluation of the effect of temperature, pH, and chemicals on bacteriocin stability and production, activity, and adsorption to target cells as well as to the cell surface of bacteriocin producers. Physiological and bio-molecular analyses based on targeting of different genes, parts of nisin operon were performed in order to investigate the hypothesis that the studied strain can produce and express nisin. Based on biochemical, physiological, and 16s rRNA analysis, the strain DF105Mi was classified as Enterococcus hirae. The selected strain produces a bacteriocin which is stable in a wide range of pH (2.0–12.0), temperature (up to 120 °C), presence of selected chemicals and presents adsorption affinity to different test organisms, process influenced by environmental conditions. Higher bacteriocin production by Ent. hirae DF105Mi was recorded during stationary growth phase, but only when the strain was cultured at 37 °C. The strain’s genetic analysis indicated presence of the genes coding for the production of the bacteriocin nisin. This result was confirmed by cross-checking the sensitivity of the produced strain to commercial nisin A. The strong anti-Listeria activity, bacteriocin adsorption, and stability of produced bacteriocin indicate that Ent. hirae DF105Mi presents a differentiated potential application for biopreservation of fermented dairy products.

     

A Protein Disulfide Isomerase Controls Neuronal Migration through Regulation of Wnt Secretion

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High-pass filtering of input signals by the Ih current in a non-spiking neuron, the retinal rod bipolar cell

Hyperpolarization-activated cyclic nucleotide-sensitive (HCN) channels mediate the I(f) current in heart and I(h) throughout the nervous system. In spiking neurons I(h) participates primarily in different forms of rhythmic activity. Little is known, however, about its role in neurons operating with graded potentials as in the retina, where all four channel isoforms are expressed. Intriguing evidence for an involvement of I(h) in early visual processing are the side effects reported, in dim light or darkness, by cardiac patients treated with HCN inhibitors. Moreover, electroretinographic recordings indicate that these drugs affect temporal processing in the outer retina. Here we analyzed the functional role of HCN channels in rod bipolar cells (RBCs) of the mouse. Perforated-patch recordings in the dark-adapted slice found that RBCs exhibit I(h), and that this is sensitive to the specific blocker ZD7288. RBC input impedance, explored by sinusoidal frequency-modulated current stimuli (0.1-30 Hz), displays band-pass behavior in the range of I(h) activation. Theoretical modeling and pharmacological blockade demonstrate that high-pass filtering of input signals by I(h), in combination with low-pass filtering by passive properties, fully accounts for this frequency-tuning. Correcting for the depolarization introduced by shunting through the pipette-membrane seal, leads to predict that in darkness I(h) is tonically active in RBCs and quickens their responses to dim light stimuli. Immunohistochemistry targeting candidate subunit isoforms HCN1-2, in combination with markers of RBCs (PKC) and rod-RBC synaptic contacts (bassoon, mGluR6, Kv1.3), suggests that RBCs express HCN2 on the tip of their dendrites. The functional properties conferred by I(h) onto RBCs may contribute to shape the retina's light response and explain the visual side effects of HCN inhibitors.