A fast algorithm for matrix balancing

As long as a square nonnegative matrix A contains sufficient nonzero elements, then the matrix can be balanced, that is we can find a diagonal scaling of A that is doubly stochastic. A number of algorithms have been proposed to achieve the balancing, the most well known of these being Sinkhorn-Knopp. In this paper we derive new algorithms based on inner-outer iteration schemes. We show that Sinkhorn-Knopp belongs to this family, but other members can converge much more quickly. In particular, we show that while stationary iterative methods offer little or no improvement in many cases, a scheme using a preconditioned conjugate gradient method as the inner iteration can give quadratic convergence at low cost

Overexpression of GA20-OXIDASE1 impacts plant height, biomass allocation and saccharification efficiency in maize

Increased biomass yield and quality are of great importance for the improvement of feedstock for the biorefinery. For the production of bioethanol, both stem biomass yield and the conversion efficiency of the polysaccharides in the cell wall to fermentable sugars are of relevance. Increasing the endogenous levels of gibberellic acid (GA) by ectopic expression of GA20-OXIDASE1 (GA20-OX1), the rate-limiting step in GA biosynthesis, is known to affect cell division and cell expansion, resulting in larger plants and organs in several plant species. In this study, we examined biomass yield and quality traits of maize plants overexpressing GA20-OX1 (GA20-OX1). GA20-OX1 plants accumulated more vegetative biomass than control plants in greenhouse experiments, but not consistently over two years of field trials. The stems of these plants were longer but also more slender. Investigation of GA20-OX1 biomass quality using biochemical analyses showed the presence of more cellulose, lignin and cell wall residue. Cell wall analysis as well as expression analysis of lignin biosynthetic genes in developing stems revealed that cellulose and lignin were deposited earlier in development. Pretreatment of GA20-OX1 biomass with NaOH resulted in a higher saccharification efficiency per unit of dry weight, in agreement with the higher cellulose content. On the other hand, the cellulose-to-glucose conversion was slower upon HCl or hot-water pretreatment, presumably due to the higher lignin content. This study showed that biomass yield and quality traits can be interconnected, which is important for the development of future breeding strategies to improve lignocellulosic feedstock for bioethanol production

Business ecosystem embeddedness to enhance supply chain competence: the key role of external knowledge capacities

This work was supported by the Spanish Ministry of Economy and Business under Grant ECO2017-84138-P; FEDER/Junta de Andaluc~iaMinistry of Economy and Knowledge under grant A-SEJ-154-UGR18. The first author's research was supported by the Spanish Ministry of Science, Innovation and Universities under FPU Predoctoral Program [Grant Ref. FPU16/04712] and complementary mobility grant for short stays [Application number EST18/00138].Interest in business ecosystems has grown exponentially over the last decade. This article focuses on the operational benefits of business ecosystems by investigating how embeddedness in business ecosystems influences supply chain competence. Specifically, it considers the mediating effect of external knowledge capacities (i.e. absorptive, desorptive and connective capacity). Data from 271 European firms in business ecosystems was collected to test the paper’s hypotheses using regression analysis with bootstrapping. Results indicate that business ecosystem embeddedness does not in itself improve supply chain competence. Rather, the relationship is explained through (i) absorptive and desorptive capacity as direct mediators; and (ii) connective capacity, which enhances supply chain competence indirectly by improving external knowledge retention for absorptive and desorptive capacity. To the best of our knowledge, this is the first paper to demonstrate benefits of being embedded in business ecosystems other than in terms of innovation. Newly validated scales for business ecosystem embeddedness and connective capacity are provided.Spanish Ministry of Economy and Business ECO2017-84138-PSpanish Ministry of Science, Innovation and Universities FPU16/04712 EST18/00138FEDER/Junta de AndaluciaMinistry of Economy and Knowledge A-SEJ-154-UGR1

Environmental practices and firm performance in emerging markets: The mediating role of product quality

Environmental practices have not received as much research attention in emerging market contexts as traditional topics like quality. However, the importance of environmental practices for a firm’s production strategy has been increasing at an unprecedented level across the globe. Our research objective is, therefore, to investigate the interplay between environmental practices and quality in the pursuit of firm performance. Relying on 492 responses from Turkish manufacturers to test our hypotheses, we show that environmental practices directly improve the quality of products over and above the effect of quality management practices in emerging markets. Product quality, in turn, is important for increasing firm performance, acting as a mediator for the positive effects of environmental practices on performance. Thus, we reveal that product quality functions as an instrumental conduit between environmental practices and firm performance in emerging markets like Turkey where stakeholder pressures are weak, and regulations are often not properly enforced.WOS:0004680055000052-s2.0-8506453448

Marchantia polymorpha model reveals conserved infection mechanisms in the vascular wilt fungal pathogen Fusarium oxysporum

How co-evolution has shaped the interaction between plants andtheir associated microbes remains a central question in organis-mic interactions (Bonfante & Genre, 2010; Delaux & Schor-nack, 2021). Plants have evolved a sophisticated and multilayeredimmune system to ward off potential microbial invaders (Jones& Dangl, 2006; Boller & Felix, 2009). In addition, pathogenshave developed mechanisms allowing them to enter living plants,colonise their tissues and overcome their defence responses.Pathogenicity factors can be either broadly conserved or speciesspecific and include regulators of cell signalling, gene expressionor development, as well as secreted effector molecules that modu-late the host environment (Jongeet al., 2011; Turr aet al., 2014;Weiberget al., 2014; Prestiet al., 2015; Ryder & Talbot, 2015;van der Does & Rep, 2017).A particularly destructive group of plant pathogens are thosecausing vascular wilt diseases, which infect the roots and colonisethe highly protected and nutrient poor niche of the xylem(Yadeta & Thomma, 2013). The ascomycete fungusFusariumoxysporum(Fo) represents a species complex with worldwidedistribution that provokes devastating losses in more than 150different crops (Deanet al., 2012). Fo exhibits a hemibiotrophlifestyle with an initial biotrophic phase characterised by intercel-lular growth in the root cortex, followed by invasion of the vascu-lature and transition to the necrotrophic phase resulting inmaceration and death of the colonised host (Redkaret al., 2021).In the soil, Fo is able to locate roots by sensing secreted plant per-oxidases via its sex pheromone receptors and the cell wallintegrity mitogen activated protein kinase (MAPK) pathway(Turr aet al., 2015). Once inside the root, the fungus secretes asmall regulatory peptide that mimics plant Rapid ALkalinisationFactor (RALF) to induce host alkalisation, which in turn activatesa conserved MAPK cascade that promotes plant invasive growth(Masachiset al., 2016). Additional pathogenicity determinantsinclude transcriptional regulators, fungus/plant cell wall remod-elling components or secondary metabolites, among others(Michielse & Rep, 2009).Individual Fo isolates exhibit host-specific pathogenicity,which is determined by lineage-specific (LS) chromosomes thatencode distinct repertoires of effectors known as Secreted inXylem (Six) (Maet al., 2010; van Damet al., 2016). Some Six proteins appear to primarily target plant defence responses, butcan also be recognised as avirulence factors by specific host recep-tors (Houtermanet al., 2009; Tintoret al., 2020). In addition tothe pathogenic forms, the Fo species complex (FOSC) alsoincludes endophytic isolates such as Fo47, which was isolatedfrom a natural disease suppressive soil (Alabouvette, 1986; Wanget al., 2020). Fo47 colonises plant roots without causing wiltsymptoms and functions as a biological control agent againstpathogenic Fo strains. How vascular wilt fungi such as Fo gainedthe ability to associate with plant hosts and evolved endophyticand pathogenic lifestyles remains poorly understood.The bryophyteMarchantia polymorpha(Mp) belongs to theancient lineage of liverworts and has emerged as the primenonvascular plant model for studying the evolution of molecularplant–microbe interactions (Evo-MPMI), due to its low geneticredundancy, the simplicity of its gene families and an accessiblemolecular genetic toolbox (Ishizakiet al., 2008; Lockhart, 2015;Bowmanet al., 2017; Upsonet al., 2018; Gimenez-Ibanezet al.,2019). Importantly, Mp possesses receptor-like kinases (RLKs),nucleotide binding, leucine-rich repeat receptors (NLRs) and sal-icylic acid (SA) pathway genes similar to those mediatingimmune signalling in angiosperms (Xueet al., 2012; Bowmanet al., 2017), therefore allowing the study of plant–microbe inter-actions across evolutionarily distant land plant lineages such asliverworts and eudicots, which diverged>450 million years ago(Ma) (Carellaet al., 2018). A current shortcoming of Mp is thatonly few pathogen infection models have been developed forin vitropathogenicity assays. These include the fungiXylariacubensisandColletotrichum sp1, the oomycetePhytophthorapalmivoraand the Gram-negative bacteriumPseudomonassyringae(Nelsonet al., 2018; Carellaet al., 2019; Gimenez-Ibanezet al., 2019). A survey of the Mp microbiome identified anumber of fungal endophytes, some of which can also act aspathogens (Matsuiet al., 2019; Nelson & Shaw, 2019). Whetherroot-infecting vascular wilt fungi can colonise this land plant lin-eage, which is evolutionarily distant to eudicots and lacks bothtrue roots and xylem, is currently unknown.Here we established a new pathosystem between Fo and Mp.We find that Fo isolates that are either endophytic or pathogenicon different crops (tomato, banana, cotton) are all able tocolonise and macerate the thallus of this nonvascular plant. Infec-tion of Mp by Fo requires fungal core pathogenicity factors,whereas LS effectors are dispensable suggesting that this vascularwilt fungus employs conserved mechanisms during infection ofevolutionarily distant plant lineages. We further show that thefungal transition from biotrophic intercellular growth tonecrotrophic maceration and sporulation, which on angiospermsrelies on host-specific factors promoting xylem invasion, occursdirectly on the nonvascular plant Mp