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Ascospores discharged at rainfall and dispersed by wind can provide long-distance spread of the European canker fungus, Neonectria ditissima. Ascospores are produced by perithecia which are the sexual reproductive stage. Diffuse knowledge exists on the seasonal pattern of perithecium formation under different climatic conditions. Therefore, the development of perithecia was observed for several successive seasons at five sites in three Northern European countries. In Norway and Finland, ripe perithecia were commonly recorded throughout the year, and on individual cankers continuously for up to 28 months. In contrast, asexual reproductive structures (sporodochia) were confined to the growing season in both countries. In Northern Germany an average of 51% of cankers developed ripe perithecia by late winter, and perithecial senescence ensued in late spring. On average, ripe perithecia were present on cankers for 22 weeks. In contrast, sporodochia were observed all year round. The timing of perithecium maturation correlated with the number of days with > 2 mm rainfall in July–September. The presence of mature perithecia and sporodochia for different lengths of time in different countries has implications for regional disease management strategies. [ABSTRACT FROM AUTHOR]

The combination of preharvest treatments with calcium chloride and fungicides, and storage of maturity graded fruit were assessed in five European plum cultivars. At harvest, samples of fruit within a commercially suitable range in ripening were divided into two categories: less-ripe (tree ripe-) and more-ripe (tree ripe+). The fruit were stored for 10–14 days at 4 °C followed by 2–3 days at 20 °C before the assessment of fungal decay. If calcium chloride was applied six times each season, postharvest fruit decay was significantly reduced in four of nine experiments, with a total mean reduction of around 50%. Two calcium applications in combination with a fungicide treatment reduced decay by approx. 60% compared to the untreated in one experiment. In six of seven experiments there was no effect of preharvest fungicide applications. In six of 10 experiments, fruit of the category tree ripe- had fewer fruit with fungal decay after storage than the tree ripe+fruit. The higher incidence in the category tree ripe+fruit was primarily due to brown rot, Mucor rot, and blue mould. For the category tree ripe+, there was two to ten times more decay than on tree ripe- fruit after a simulated shelf-life period. To ensure low incidence of fungal decay, fruit of commercial harvest maturity may thus be separated in two ripening categories, one for rapid distribution to the market (tree ripe+) and another for extended distribution time (tree ripe-). [ABSTRACT FROM AUTHOR]

The growing global population has intensified concerns about food security, making it essential to produce crops sustainably to meet increasing demands without harming the environment. In this regard, biological control agents (BCAs) have recently gained more attention owing to their potential to manage fungal diseases of crops, particularly in the Solanaceae family. The proper use of selected BCAs such as Trichoderma spp., Bacillus spp., Pseudomonas fluorescens, Beauveria bassiana, and Gliocladium spp. has several benefits for Solanaceae crops. This review aims to summarize the effectiveness of various biological control strategies for fungal diseases in Solanaceae crops. We also provide basic knowledge on BCAs along with suggestions for further research to reduce the severity of these destructive diseases.Article highlights: Solanaceae crops are susceptible to various fungal pathogens, leading to significant yield losses. BCAs such as Trichoderma spp., Bacillus spp., Pseudomonas fluorescens, Beauveria bassiana, and Gliocladium spp. effectively manage fungal diseases in Solanaceae crops. Molecular mechanisms of BCAs involve activation of plant defense pathways and production of antifungal compounds. Integrating BCAs with other disease management strategies enhances their efficacy and reduces reliance on chemical fungicides. Emerging trends in BCA research focus on microbial consortia, endophytic bacteria, and modern biotechnological tools. [ABSTRACT FROM AUTHOR]

This review covers the situation with resistance to various systemic fungicides being developed in Venturia inaequalis worldwide and in Russia assessing the prospects for their further use. Information is provided about all fungicides used in Russia against apple scab and their efficacy at this point in time and each chemical class is described. Data are presented on the mechanisms of resistance to chemicals in the pathogen including at the molecular level. The problem of resistance of V. inaequalis and ways of solving it at the present level of scientific knowledge are discussed. [ABSTRACT FROM AUTHOR]

Three novel phenolic compounds were isolated from the heartwood of Millettia pendula along with eight known compounds. Among the known compounds, six were isolated from this species for the first time. Structural determination of the isolated compounds was accomplished using 1D and 2D nuclear magnetic resonance spectroscopy and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Two of the isolated compounds, 2 and 6, showed red and purple pigmentation, respectively. These compounds contained a conjugated π system composed of benzofuran and p-benzoquinone moieties. We therefore hypothesize that a hydroquinone moiety, present in precursors of 2 and 6, is autoxidized by activated oxygen in the air to form p-benzoquinone. The difference in colors between these two compounds was due to the difference in the B ring substituents. Expansion of their conjugated pi systems allows 2 and 6 to absorb and reflect light in the visible region, and results in the characteristic purple coloring of M.pendula. [ABSTRACT FROM AUTHOR]

Various gender biases have been demonstrated in early childhood educators (ECEs) with unintentional preferential treatment provided to boys during STEM-related play activities. These biases could impact young girls' identity formation, resulting in continued underrepresentation of women in STEM domains in future. In China, however, little research has been conducted on how ECEs perceive gender equity of STEM fields. Consequently, this study aims to close this gap by investigating the educators' perceptions on and responses to gender differences in STEM play, drawing on the cultural-historical theory and incorporating feminist perspectives. Adopting a multiple-case study approach, this study collected perceptions and experiences of six Chinese in-service ECEs regarding STEM play and gender-related issues. The participants recognized and valued children's equal involvement in STEM play, but failed to preclude ingrained gender preconceptions, leading to contradictory beliefs and performs. Meanwhile, Chinese ECEs considered prejudices from the external environment and peer influence the main obstacles to gender inclusion. Inclusive practices and emphasises are thus discussed relating to ECEs' multiple roles in supporting gender-neutral environments for STEM play. These preliminary findings shed light on attaining gender equity in STEM within the context of a feminist discourse, and provide Chinese educators, leaders and even the educational system with pioneering information. However, further research on ECEs' underlying stereotypes and teaching practices is still warranted to examine future professional development possibilities, support ECEs in reducing obstacles to girls' STEM engagement, and ultimately create a welcoming and inclusive STEM play space for girls. [ABSTRACT FROM AUTHOR]

Immune systems are of pivotal importance to any living organism on Earth, as they protect the organism against deleterious effects of viral infections. Though the current knowledge about these systems is still biased towards the immune response in vertebrates, some studies have focused on the identification and characterization of components of invertebrate antiviral immune systems. Two classic model organisms, the insect Drosophila melanogaster and the nematode Caenorhabditis elegans, were instrumental in the discovery of several important components of the innate immune system, such as the Toll-like receptors and the RNA interference pathway. However, these two model organisms provide only a limited view of the evolutionary history of the immune system, as they both are ecdysozoan protostomes. Recent functional studies in non-classic models such as unicellular holozoans (for example, choanoflagellates), lophotrochozoans (for example, oysters) and cnidarians (for example, sea anemones) have added crucial information for understanding the evolution of antiviral systems, as they revealed unexpected ancestral complexity. This Review aims to summarize this information and present the ancestral nature of the antiviral immune response in animals. We also discuss lineage-specific adaptations and future perspectives for the comparative study of the innate immune system that are essential for understanding its evolution., (© 2023. Springer Nature Limited.)

Neonectria fruit rot (NFR), an apple disease caused by the fungus Neonectria ditissima, is common in Brazilian orchards, but several aspects of its epidemiology are not well elucidated. The objectives of this study were to: i) test in vitro germination of ascospores at different temperatures and wetness periods and compare with conidia germination, ii) evaluate and compare the monocyclic components of NFR caused by conidia and ascospore infection in wounded and unwounded ripe detached 'Gala' apple and iii) evaluate and compare the monocyclic components of NFR caused by conidia infection in 'Rocha' pear fruit under different temperatures. Germination of conidia and ascospores occurred in the range of 12–28 °C. At 35 °C no germination occurred, for both ascospores and conidia, regardless of the wetness period (3–60 h). With the same wetness period, conidia germination was always higher than ascospores at any temperature. For ascospores, the optimal temperature for germination ranged from 18–21 °C, lower than the estimated for conidia, which ranged from 21 to 24 °C. In wounded detached apple fruit, the incubation period varied from 35 to 49 days after ascospore inoculation, and for conidia from 14 to 42 days. When comparing the same temperatures, mean lesion growth rate was always higher for fruits inoculated with conidia than with ascospores. Unwounded fruits inoculated in the calyx-end did not present Neonectria fruit rot symptoms. The disease on 'Rocha' pear fruit has shorter incubation and latent periods than those of 'Gala' apple and higher AUDPC at 25 °C. The fast monocycle development represents a risk if the disease spread to pear orchards but also sets pear fruit as a good option for future NFR control studies. [ABSTRACT FROM AUTHOR]

Apple is the most important fruit tree in West Azarbaijan province of Iran. In a survey of apple orchards, a disease with crown and collar canker and necrosis symptoms was observed in three young apple orchards in Urmia, affecting 15% and 1% of 'Red Delicious' and 'Golden Delicious' cultivars, respectively. A fungus with typical characteristics of the asexual morph of Cytospora was regularly isolated from the diseased tissues. Morphological characteristics and phylogenetic analyses inferred from the combined dataset of the ITS-rDNA, parts of LSU, tef1-α, rpb2, and act1 genes revealed that the isolates represent a new species of Cytospora, described herein as Cytospora balanejica sp. nov.. The pathogenicity of all isolates was confirmed on apple cv. 'Red Delicious' based on Koch's postulates. Also, the reaction of 12 other apple cultivars was assessed against five selected isolates with the highest virulence. The results showed that except for cv. 'Braeburn', which did not produce any symptoms of the disease, the other 11 cultivars showed characteristic disease symptoms including sunken and discolored bark and wood. The mean length of the discolored area was different among the 11 so-called susceptible cultivars, hence cvs. 'M4' and 'Golden Delicious' showed the highest and the lowest lesion length, respectively. Moreover, the aggressiveness of the five tested isolates was different, and the isolates BA 2-4 and BA 3-1 had the highest and lowest aggressiveness, respectively. Based on our observations on the potential ability of the fungus to cause disease on young and actively growing apple trees, it will be a serious threat to apple cultivation and industry. [ABSTRACT FROM AUTHOR]

The maximal number of repetitions that can be completed at various percentages of the one repetition maximum (1RM) [REPS ~ %1RM relationship] is foundational knowledge in resistance exercise programming. The current REPS ~ %1RM relationship is based on few studies and has not incorporated uncertainty into estimations or accounted for between-individuals variation. Therefore, we conducted a meta-regression to estimate the mean and between-individuals standard deviation of the number of repetitions that can be completed at various percentages of 1RM. We also explored if the REPS ~ %1RM relationship is moderated by sex, age, training status, and/or exercise. A total of 952 repetitions-to-failure tests, completed by 7289 individuals in 452 groups from 269 studies, were identified. Study groups were predominantly male (66%), healthy (97%), < 59 years of age (92%), and resistance trained (60%). The bench press (42%) and leg press (14%) were the most commonly studied exercises. The REPS ~ %1RM relationship for mean repetitions and standard deviation of repetitions were best described using natural cubic splines and a linear model, respectively, with mean and standard deviation for repetitions decreasing with increasing %1RM. More repetitions were evident in the leg press than bench press across the loading spectrum, thus separate REPS ~ %1RM tables were developed for these two exercises. Analysis of moderators suggested little influences of sex, age, or training status on the REPS ~ %1RM relationship, thus the general main model REPS ~ %1RM table can be applied to all individuals and to all exercises other than the bench press and leg press. More data are needed to develop REPS ~ %1RM tables for other exercises. [ABSTRACT FROM AUTHOR]

Recently, Buan and Marsh showed that if two complete τ -exceptional sequences agree in all but at most one term, then they must agree everywhere, provided the algebra is τ -tilting finite. They conjectured that the result holds without that assumption. We prove their conjecture. Along the way, we also show that the dimension vectors of the modules in a τ -exceptional sequence are linearly independent. [ABSTRACT FROM AUTHOR]

Coastal zones supporting diurnal shelf waves near the South Kuril Islands were determined based on the analysis of small-scale amplitude and phase variations of diurnal O1 and K1 tidal waves estimated from along-track TOPEX/Poseidon altimetry data. The amplitudes and phases of these waves were revealed not only along the original tracks (1992–2002), but also along those shifted by half the intertrack distance (2002–2005). This made it possible to more accurately determine the zone supporting diurnal shelf waves. It was found that diurnal shelf waves in the form of baroclinic coastal trapped modes strongly influence tidal motions on the oceanic shelf of Urup and Iturup islands. Two wavelengths fit in this section of the shelf (one pair of quasi-stationary eddies is localized on the shelf of Urup Island and a second one on the shelf of Iturup Island). This is an unexpected result, as barotropic shelf modes usually form one pair of eddies (for example, on the northeastern shelf of Sakhalin Island, on the northern shelf of Hokkaido Island and on the oceanic shelf of the North Kuril Islands). We found that the zone of K1 and O1 tidal waves start from Chirpoi Island, which means that shelf waves are generated as a result of the diffraction of a large-scale Kelvin tidal wave in the deep Bussol Strait. The existence of the lower frequency O1 tidal shelf wave was found not only on the shelf of Urup and Iturup islands, but also on the shelf of Shikotan Island, which is consistent with the earlier results of Yefimov and Rabinovich (1980). Diurnal shelf waves cause significant increases in the O1 and K1 amplitudes on the coast of Iturup Island (especially at its southern part) and on Urup Island in comparison with the open ocean, and produce strong instrumentally-observed diurnal tidal currents in these regions. Baroclinic diurnal shelf (coastal trapped) waves also contribute to vertical movements, forcing water temperature variations at sufficiently great depths, which can have a significant impact on the living conditions of benthic communities. [ABSTRACT FROM AUTHOR]

Easily accessible BINOL-based monodentate phosphite ligand L1 and hybrid ligand L2 have been synthesized in good yield by following a one-pot, two-step protocol. A single 31P resonance at 146.6 ppm confirmed the formation of L1. Subsequent 1-2D NMR and mass spectrometric analysis authenticated the existence of L1. These ligands afforded excellent activity and regio-selectivity in the Rh-catalyzed AHF of styrenic substrates. L1 showed excellent regioselectivity but did not discriminate between the two enantiomers, while L2 displayed an enantiomeric excess (ee) of up to 20%. In our attempts to understand the reasons for low ee, the coordination behavior of L2 was investigated. The coordination study revealed that L2 coordinates with the Rh as a monodentate ligand, although there are two P-sites. It was found that only the phosphine arm was coordinated to the Rh and the phosphite arm stayed away from the Rh core at the ambient temperature, leading to moderate ee. One-step synthesis of a phosphite (L1) and a phosphine-phosphite (L2) ligand and their implication in the asymmetric hydroformylation of olefins with excellent regioselectivity (>95%) and moderate enantioselectivity (up to 20%) is reported. [ABSTRACT FROM AUTHOR]

The paper analyzes the parameters of gas streams after the triple-shock configuration, which forms in Mach reflection with normal Mach shock (so-called stationary Mach configuration). We suppose that this stationary Mach configuration moves in a counter flow with arbitrary velocity (or Mach number). Analyzing the relation of dynamical pressures across the contact discontinuity, which issues from the triple point of the Mach reflection, we have shown that the streams after the triple-shock configuration differs much in their translational action of surrounding objects. [ABSTRACT FROM AUTHOR]

Additive categories play a fundamental role in mathematics and related disciplines. Given an additive category equipped with a biadditive functor, one can construct its category of extensions, which encodes important structural information. We study how functors between categories of extensions relate to those at the level of the original categories. When the additive categories in question are n-exangulated, this leads to a characterisation of n-exangulated functors. Our approach enables us to study n-exangulated categories from a 2-categorical perspective. We introduce n-exangulated natural transformations and characterise them using categories of extensions. Our characterisations allow us to establish a 2-functor between the 2-categories of small n-exangulated categories and small exact categories. A similar result with no smallness assumption is also proved. We employ our theory to produce various examples of n-exangulated functors and natural transformations. Although the motivation for this article stems from representation theory and the study of n-exangulated categories, our results are widely applicable: several require only an additive category equipped with a biadditive functor with no extra assumptions; others can be applied by endowing an additive category with its split n-exangulated structure. [ABSTRACT FROM AUTHOR]

ASIC channels are bilaterian proton-gated sodium channels belonging to the large and functionally-diverse Deg/ENaC family that also includes peptide- and mechanically-gated channels. Here, we report that the non-bilaterian invertebrate Trichoplax adhaerens possesses a proton-activated Deg/ENaC channel, TadNaC2, with a unique combination of biophysical features including tachyphylaxis like ASIC1a, reduced proton sensitivity like ASIC2a, biphasic macroscopic currents like ASIC3, as well as low sensitivity to the Deg/ENaC channel blocker amiloride and Ca2+ ions. Structural modeling and mutation analyses reveal that TadNaC2 proton gating is different from ASIC channels, lacking key molecular determinants, and involving unique residues within the palm and finger regions. Phylogenetic analysis reveals that a monophyletic clade of T. adhaerens Deg/ENaC channels, which includes TadNaC2, is phylogenetically distinct from ASIC channels, instead forming a clade with BASIC channels. Altogether, this work suggests that ASIC-like channels evolved independently in T. adhaerens and its phylum Placozoa. Our phylogenetic analysis also identifies several clades of uncharacterized metazoan Deg/ENaC channels, and provides phylogenetic evidence for the existence of Deg/ENaC channels outside of Metazoa, present in the gene data of select unicellular heterokont and filasterea-related species. The non-bilaterian Trichoplax adhaerens has a proton-activated Deg/ENaC channel with ASIC-like biophysical properties but distinct determinants for proton gating. Phylogenetic evidence for the existence of Deg/ENaC channels outside of animals is also provided. [ABSTRACT FROM AUTHOR]

The present work is a numerical follow-up on our published experimental paper on shock ignition of aluminium particle clouds in the low-temperature regime. The in-house multi-phase regularized smoothed particle hydrodynamics (MP-RSPH) code is used to perform numerical simulations with an increasing degree of complexity, looking at single-phase, inert, and reactive particles in separate simulations. The first part of the paper gives a short description of the additional physics added to the code. Based on the experimental results, the numerical code is then used to estimate the particle temperature at the time of ignition. Results from simulations with three different numerical descriptions, the diffusive, kinetic, and total burn rates, are then compared to the experimental results. The two diffusive burn rate simulations (K &H and O &H) show the best fit to the experimental results. The burn rate formula based on our experimental data (O &H) is preferred, since it has the gas temperature dependency included and does not require additional parameter adjustments. The results from the numerical simulations support the theory that the observed aluminium particle cloud burning process is diffusive, as indicated in the experimental paper. [ABSTRACT FROM AUTHOR]

Over the past two decades, there has been a marked increase in Uruguayan olive production. However, the humid climate of Uruguay creates favorable conditions for the development of olive anthracnose, characterized by fruit rots and blossom blight, which are frequent and destructive symptoms. Several species of Colletotrichum are responsible for the disease, with C. acutatum sensu stricto (s.s) being the most prevalent. This study aimed to analyze the survival of Colletotrichum in an olive orchard with a history of olive anthracnose. For two consecutive years, samples of fruits, leaves, and woody organs were collected monthly from aerial parts of the olive tree. Colletotrichum spp. structures were recorded in a climate chamber, and C. acutatum s.s. was quantified. The study demonstrated that Colletotrichum can survive in different organs of the olive tree, with mummified fruit being the primary survival site, followed by leaves and branches. Among the leaf and woody organs, yellow leaves, leaves from defoliated branches, terminal dry branches, and healthy new branches were identified as important survival sites. Mummified fruits were not always present on the tree throughout the year, and leaves and branches can serve as the primary source of initial inoculum for infections of flowers and fruits in their absence. [ABSTRACT FROM AUTHOR]

European canker is one of the most devastating fungal diseases of apple in most temperate regions. The causal agent, Neonectria ditissima, infects trees through wounds in the bark forming cankers that girdle the stem and eventually cause tree death. Timely protection of the trees is challenged by stagnation of symptom expression after infections for a long period of time. The objective of this research is to use a novel TaqMan PCR assay to detect and quantify N. ditissima during the asymptomatic colonization of apple wood. Pruning wounds on branches of the cultivars Elstar and Gala were inoculated with N. ditissima and wood discs were sampled at 2–6, 10–14, and 30–34 mm distance from the inoculation site after 3 hours, 2 weeks, 4 weeks and 8 weeks for the detection and quantification of the pathogen. The TaqMan PCR assay detected N. ditissima in 51% of the inoculated apple tree samples. This was more sensitive than the culturing method detecting N. ditissima in 11% of the samples. An accumulation of N. ditissima DNA up to 34 mm distance from the inoculation site was observed without development of visible symptoms. To our knowledge this is the first time colonization of N. ditissima was detected and quantified in the absence of symptoms of European canker. The implications of this research are discussed. [ABSTRACT FROM AUTHOR]

The rise of residues derived from hydrometallurgical processes of zinc production has made this industry face numerous challenges. Residues contain elements whose reclamation is of high significance due to the economic improvement of the whole process and the removal of environmental consequences. The previous study examined the selective extraction of Zn and As from hot purification filter cakes of the zinc process and found that the dominant species in arsenic-bearing solution was AsO43−. With a Zn2(AsO4) (OH) composition containing As 23.1 wt pct, As was precipitated with an 95 pct efficiency by adding zinc sulfate under the following conditions: Molar ratio Zn/As = 1, pH 6.5, time = 4 hours, temperature = 80 °C, and stirring velocity = 500 rpm. The zinc arsenate hydroxide was successfully used as an activator of the zinc powder in the cobalt cementation process. The examination of the precipitate revealed that As increased the anodic and cathodic reactions potential difference. Thus, thermodynamic driving force of the reaction increased and cementation improved by forming intermediate compounds, like CoAs, with higher stability and more positive reduction potential. [ABSTRACT FROM AUTHOR]

Fruit cracking caused by rainfall prior to harvest, a major problem in sweet cherry production, is being exacerbated by climate change. Currently, pre-harvest spraying with calcium salt solutions is the prevalent technique to reduce fruit cracking in cherry orchards not covered by plastic roofs. This study evaluated the effectiveness of canopy-applied silicon in the reduction of sweet cherry cracking under different field conditions. Four field trials were conducted on mature trees of the cultivars Van, New Star, and Emperor Francis. Treatments included water (control), calcium chloride, and sodium silicate. Multiple sprays (three) were applied weekly from fruit onset of color to approximately 1 week before harvest. The results showed that under conditions conducive to cracking, sodium silicate reduced the percentage of cracked fruits to a similar or larger extent than calcium chloride. This study highlights how canopy-applied silicon sources may effectively contribute to reducing cherry cracking, acting as an alternative technique to other preventive methods. [ABSTRACT FROM AUTHOR]

Understanding how brains evolved is critical to determine the origin(s) of centralized nervous systems. Brains are patterned along their anteroposterior axis by stripes of gene expression that appear to be conserved, suggesting brains are homologous. However, the striped expression is also part of the deeply conserved anteroposterior axial program. An emerging hypothesis is that similarities in brain patterning are convergent, arising through the repeated co-option of axial programs. To resolve whether shared brain neuronal programs likely reflect convergence or homology, we investigated the evolution of axial programs in neurogenesis. We show that the bilaterian anteroposterior program patterns the nerve net of the cnidarian Nematostella along the oral-aboral axis arguing that anteroposterior programs regionalized developing nervous systems in the cnidarian–bilaterian common ancestor prior to the emergence of brains. This finding rejects shared patterning as sufficient evidence to support brain homology and provides functional support for the plausibility that axial programs could be co-opted if nervous systems centralized in multiple lineages. [ABSTRACT FROM AUTHOR]

This study evaluated the risks for injury and death to occupants from blast waves to the side and underbody of an armored passenger-vehicle and to ground personnel from free-field blast waves. The Kingery-Bulmash empirical relationships for explosive shock waves were augmented by the Swisdak empirical relations for stand-off distances up to Z = 39.8 m/kg1/3 to tabulate shock-wave characteristics using the Friedlander wave-shape. A 15 kg, hemispherical explosion was analyzed in detail for the shock wave velocity and compression of air behind the wave front. An armored SUV was analyzed with Z = 1.6 m/kg1/3 (4 m) standoff distance from pressure loading on the near-side, far-side and underbody. The rigid body displacement was 0.36 m and 7.8° yaw for a side loading. When a segment of the occupant compartment accelerates inward, there are risks for injury from the intrusion. Energy is transferred to the occupant by deformation of their body (Ed) and by velocity increasing the kinetic energy of the body region (Ek). Body deformation injures an occupant by exceeding the tolerable compression (crush mechanism) or exceeding the rate-dependent tolerance, which is defined by the rate times the extent of compression (viscous mechanism). The risk for injury and death to ground personnel was analyzed for free-field blast waves by stand-off distance and TNT weight. A 15 kg charge posed a 99% risk of death at 3.9 m, 50% risk at 5.2 m, 1% risk at 7.8 m and injury threshold at 8.2 m. A 100 kg charge posed a 99% risk of death at 8.5 m, 50% risk at 11.6 m, 1% risk at 17.3 m and injury threshold at 18.0 m. The study describes the steps to analyze blast loading of an armored passenger-vehicle for risks of occupant injury. It describes the steps to analyze injury risks to ground personnel from blast wave pressure. [ABSTRACT FROM AUTHOR]

Comparative studies of different isolates of Neonectria ditissima obtained from canker lesions and rotten fruit showed that both five-septate macroconidia and aseptate microconidia were capable of germination by germ-tube formation, but that growth commenced earlier and proceeded faster from the former than the latter type of spore. Further, following wound inoculation of apple fruit with different numbers of conidia (50, 500 or 5000 per wound) the resulting rot lesions were always significantly larger with macroconidia than microconidia, and in both conidial types lesion size increased with higher inoculum loads. These data confirm that microconidia are capable of causing infections, but indicate that their contribution to the success of the pathogen in the field is probably negligible. [ABSTRACT FROM AUTHOR]

Ion channels of the DEG/ENaC family share a similar structure but serve strikingly diverse biological functions, such as Na+ reabsorption, mechanosensing, proton-sensing, chemosensing and cell-cell communication via neuropeptides. This functional diversity raises the question of the ancient function of DEG/ENaCs. Using an extensive phylogenetic analysis across many different animal groups, we found a surprising diversity of DEG/ENaCs already in Cnidaria (corals, sea anemones, hydroids and jellyfish). Using a combination of gene expression analysis, electrophysiological and functional studies combined with pharmacological inhibition as well as genetic knockout in the model cnidarian Nematostella vectensis, we reveal an unanticipated role for a proton-sensitive DEG/ENaC in discharge of N. vectensis cnidocytes, the stinging cells typifying all cnidarians. Our study supports the view that DEG/ENaCs are versatile channels that have been co-opted for diverse functions since their early occurrence in animals and that respond to simple and ancient stimuli, such as omnipresent protons.Phylogenetic analyses demonstrate a remarkable variety of the degenerin/epithelial Na+ channel (DEG/ENaC) superfamily in Cnidaria and discern an unexpected role for a proton-sensitive DEG/ENaC in N. vectensis cnidocyte discharge. [ABSTRACT FROM AUTHOR]

The mesoderm gives rise to several key morphological features of bilaterian animals including endoskeletal elements and the musculature. A number of regulatory genes involved in mesoderm and/or muscle formation (e.g., Brachyury (Bra), even-skipped (eve), Mox, myosin II heavy chain (mhc)) have been identified chiefly from chordates and the ecdysozoans Drosophila and Caenorhabditis elegans, but data for non-model protostomes, especially those belonging to the ecdysozoan sister clade, Lophotrochozoa (e.g., flatworms, annelids, mollusks), are only beginning to emerge. Within the lophotrochozoans, Mollusca constitutes the most speciose and diverse phylum. Interestingly, however, information on the morphological and molecular underpinnings of key ontogenetic processes such as mesoderm formation and myogenesis remains scarce even for prominent molluscan sublineages such as the bivalves. Here, we investigated myogenesis and developmental expression of Bra, eve, Mox, and mhc in the quagga mussel Dreissena rostriformis, an invasive freshwater bivalve and an emerging model in invertebrate evodevo. We found that all four genes are expressed during mesoderm formation, but some show additional, individual sites of expression during ontogeny. While Mox and mhc are involved in early myogenesis, eve is also expressed in the embryonic shell field and Bra is additionally present in the foregut. Comparative analysis suggests that Mox has an ancestral role in mesoderm and possibly muscle formation in bilaterians, while Bra and eve are conserved regulators of mesoderm development of nephrozoans (protostomes and deuterostomes). The fully developed Dreissena veliger larva shows a highly complex muscular architecture, supporting a muscular ground pattern of autobranch bivalve larvae that includes at least a velum muscle ring, three or four pairs of velum retractors, one or two pairs of larval retractors, two pairs of foot retractors, a pedal plexus, possibly two pairs of mantle retractors, and the muscles of the pallial line, as well as an anterior and a posterior adductor. As is typical for their molluscan kin, remodelling and loss of prominent larval features such as the velum musculature and various retractor systems appear to be also common in bivalves. [ABSTRACT FROM AUTHOR]

Teachers' pedagogical practices have been consistently highlighted either as a support, or as a barrier, to girls' science, technology, engineering, and mathematics (STEM) engagement. Research suggests that teachers can display forms of gender bias during STEM experiences, such as unintentionally favouring boys in STEM participation. Investigation into early childhood and primary STEM education highlights teacher professional development as a priority, with a key focus on the awareness of gender issues. This study explores whether and how the STEM practices of early childhood teachers change and develop towards supporting girls' STEM engagement through Conceptual PlayWorlds as a model of practice. Through an educational experiment, the study design involved professional development workshops introducing teachers to the Conceptual PlayWorld model for the intentional teaching of STEM, with ideas on how to engage girls through the five characteristics of a Conceptual PlayWorld. Interview responses of seven teachers and one assistant principal regarding their experience of teaching STEM through Conceptual PlayWorlds are analysed in line with the cultural-historical approach. Findings highlight the teachers' developing consciousness regarding girls' STEM engagement through participation in the professional development workshops and Conceptual PlayWorlds, creating a shift in their teaching practices towards becoming more agentic in actively engaging girls with STEM. It is argued that while increasing teachers' consciousness informed and transformed their STEM practices, leading to teacher development, further relevant and meaningful professional development opportunities are required to support early childhood teachers in positioning STEM as a truly welcoming and inclusive space for girls. [ABSTRACT FROM AUTHOR]

Prolonged periods of leaf wetness, high temperatures, and relative humidity during spring/summer are ideal conditions for the development of apple diseases in Brazil. In 2012, European canker, caused by Neonectria ditissima was officially confirmed in Brazilian apple orchards. The disease has a high potential to adversely affect fruit production as all symptomatic branches and/or all apple trees need to be eliminated to contain the epidemic in the orchards. Knowledge of N. ditissima spore release is required to optimize management practices because it facilitates the prediction of European canker infection risks and improves disease management decisions. Thus, the objective of this study was to investigate the release of N. ditissima spores from apple plants and detached branches over time. In the São Joaquim region of Brazil, both conidia and ascospores of N. ditissima can be released from cankers alive and/or dead in apple tissues year-round. In Brazil, peaks of spore release from N. ditissima were observed in traps when there was rainfall, irrespective of the season. Ascospore peaks were more frequent and higher than those of conidia trapped in both traps and apple tissues. Detached branches of symptomatic apple trees actively released spores of N. ditissima in the three years of evaluation, but in smaller numbers in comparison to traps with live plants. Thus, new and rigorous management measures should be adopted to control European canker dissemination in Brazilian apple orchards. [ABSTRACT FROM AUTHOR]

Molecular methods have revolutionised virtually every area of biology, and metazoan phylogenetics is no exception: molecular phylogenies, molecular clocks, comparative phylogenomics, and developmental genetics have generated a plethora of molecular data spanning numerous taxa and collectively transformed our understanding of the evolutionary history of animals, often corroborating but at times opposing results of more traditional approaches. Moreover, the diversity of methods and models within molecular phylogenetics has resulted in significant disagreement among molecular phylogenies as well as between these and earlier phylogenies. How should this broad and multifaceted problem be tackled? I argue that the answer lies in integrating evidence to infer the best evolutionary scenario. I begin with an overview of recent development in early metazoan phylogenetics, followed by a discussion of key conceptual issues in phylogenetics revolving around phylogenetic evidence, theory, methodology, and interrelations thereof. I then argue that the integration of different kinds of evidence (e.g. molecular, morphological, ecological) is necessary for arriving at the best evolutionary scenario (causal explanation) rather than merely the best-fitting cladogram (statistical explanation). Finally, I discuss the prospects of this view in stimulating interdisciplinary cross-talk in early metazoan research and beyond, and challenges that need to be overcome. [ABSTRACT FROM AUTHOR]

Metal-catalysed reactions are often hypothesized to proceed on bifunctional active sites, whereby colocalized reactive species facilitate distinct elementary steps in a catalytic cycle1–8. Bifunctional active sites have been established on homogeneous binuclear organometallic catalysts9–11. Empirical evidence exists for bifunctional active sites on supported metal catalysts, for example, at metal–oxide support interfaces2,6,7,12. However, elucidating bifunctional reaction mechanisms on supported metal catalysts is challenging due to the distribution of potential active-site structures, their dynamic reconstruction and required non-mean-field kinetic descriptions7,12,13. We overcome these limitations by synthesizing supported, atomically dispersed rhodium–tungsten oxide (Rh-WOx) pair site catalysts. The relative simplicity of the pair site structure and sufficient description by mean-field modelling enable correlation of the experimental kinetics with first principles-based microkinetic simulations. The Rh-WOx pair sites catalyse ethylene hydroformylation through a bifunctional mechanism involving Rh-assisted WOx reduction, transfer of ethylene from WOx to Rh and H2 dissociation at the Rh-WOx interface. The pair sites exhibited >95% selectivity at a product formation rate of 0.1 gpropanal cm−3 h−1 in gas-phase ethylene hydroformylation. Our results demonstrate that oxide-supported pair sites can enable bifunctional reaction mechanisms with high activity and selectivity for reactions that are performed in industry using homogeneous catalysts.Catalysts consisting of oxide-supported pair sites can enable bifunctional reaction mechanisms with high activity and selectivity for reactions and so overcome the limitations in industry imposed by the use of homogeneous catalysts. [ABSTRACT FROM AUTHOR]

This paper aims at describing the process for assessing the intervention fidelity of a randomized controlled trial (RCT) of an "Adolescent Coping with Depression Course" (ACDC) and to assess the participants' satisfaction with the intervention. We applied the comprehensive fidelity model developed by the National Institutes of Health's Behavior Change Consortium to examine how our intervention met the fidelity requirements under five categories. Data came from a two-arm parallel cluster RCT. Both qualitative and quantitative analyses of the ACDC intervention using the comprehensive fidelity model indicated that the level of fidelity in this study did not reach 100%. However, it was approaching a high level of treatment fidelity. Participants also expressed high levels of satisfaction (M = 3.65, SD =.95). This analysis is important to show how appropriately the intervention was implemented, areas for improvement to increase its fidelity, and to ensure the internal and external validity of the findings. Trial Registration: ISRCTN registry ISRCTN19700389. Registered 6 October 2015. https://doi.org/10.1186/ISRCTN19700389. Full Protocol: https://doi.org/10.1186/s12888-016-0954-y [ABSTRACT FROM AUTHOR]

Reconstructing ancestral species is a challenging endeavour: fossils are often scarce or enigmatic, and inferring ancestral characters based on novel molecular approaches (e.g. comparative genomics or developmental genetics) has long been controversial. A key philosophical challenge pertinent at present is the lack of a theoretical framework capable of evaluating inferences of homology made through integration of multiple kinds of evidence (e.g. molecular, developmental, or morphological). Here, I present just such a framework. I start with a brief history and critical assessment of attempts at inferring morphological homology through developmental genetics. I then bring attention to a recent model of homology, namely Character Identity Mechanisms (DiFrisco et al. 2020), intended partly to elucidate the relationships between morphological characters, developmental genetics, and homology. I utilise and build on this model to construct the evaluative framework mentioned above, which judges the epistemic value of evidence of each kind in each particular case based on three proposed criteria: effectiveness, admissibility, and informativity, as well as providing a generalised guideline on how it can be scientifically operationalised. I then point out the evolution of the eumetazoan body plan as a case in point where the application of this framework can yield satisfactory results, both empirically and conceptually. I will conclude with a discussion on some potential implications for more general philosophy of biology and philosophy of science, especially surrounding evidential integration, models and explanation, and reductionism. [ABSTRACT FROM AUTHOR]

Geohazards, including the landslide, debris flow, rockfall, surface collapse, surface subsidence, and surface cracks, can bring great threats to human life and property. Generally, the defromation and failure of rock and soil masses can induce geohazards. To effectively predict and prevent geohazards, it is significant to capture the deformation and failure characteristics of rock and soil masses occurring in geohazards. Numerical modeling methods have been widely used to investigate the deformation and failure of rock and soil masses due to their low cost and convenience. Commonly, meshfree methods can be used to model the large deformation and failure characteristics of rock and soil masses without mesh-dependence. In this paper, we aim to provide a survey of related applications in modeling the deformation and failure of rock and soil masses occurring in common geohazards by using four frequently-used meshfree methods, including Smoothed Particle Hydrodynamics (SPH), Material Point Method (MPM), Discrete Element Method (DEM), and Discontinuous Deformation Analysis (DDA). Moreover, the capabilities, key issues, and outlook of the surveyed meshfree methods in the deformation and failure simulation of rock and soil masses are discussed. This paper provides a reference for geohazards prevention from the perspective of modeling the deformation and failure of rock and soil masses using meshfree methods. [ABSTRACT FROM AUTHOR]

Main conclusion: The present review summarizes recent advances in the understanding of 6mA in DNA as an emergent epigenetic mark with distinctive characteristics, discusses its importance in plant genomes, and highlights its chemical nature and functions. Adenine methylation is an epigenetic modification present in DNA (6mA) and RNA (m6A) that has a regulatory function in many cellular processes. This modification occurs through a reversible reaction that covalently binds a methyl group, usually at the N6 position of the purine ring. This modification carries biophysical properties that affect the stability of nucleic acids as well as their binding affinity with other molecules. DNA 6mA has been related to genome stability, gene expression, DNA replication, and repair mechanisms. Recent advances have shown that 6mA in plant genomes is related to development and stress response. In this review, we present recent advances in the understanding of 6mA in DNA as an emergent epigenetic mark with distinctive characteristics. We discuss the key elements of this modification, focusing mainly on its importance in plant genomes. Furthermore, we highlight its chemical nature and the regulatory effects that it exerts on gene expression and plant development. Finally, we emphasize the functions of 6mA in photosynthesis, stress, and flowering. [ABSTRACT FROM AUTHOR]

CO2-rich planetary atmospheres are continuously exposed to ionising radiation driving major photochemical processes. In the Martian atmosphere, CO2 clusters are predicted to exist at high altitudes motivating a deeper understanding of their photochemistry. In this joint experimental-theoretical study, we investigate the photoreactions of CO2 clusters (≤2 nm) induced by soft X-ray ionisation. We observe dramatically enhanced production of O 2 + from photoionized CO2 clusters compared to the case of the isolated molecule and identify two relevant reactions. Using quantum chemistry calculations and multi-coincidence mass spectrometry, we pinpoint the origin of this enhancement: A size-dependent structural transition of the clusters from a covalently bonded arrangement to a weakly bonded polyhedral geometry that activates an exothermic reaction producing O 2 + . Our results unambiguously demonstrate that the photochemistry of small clusters/particles will likely have a strong influence on the ion balance in atmospheres. In the Martian atmosphere, CO2 clusters are predicted to exist at high altitudes motivating a deeper understanding of their photochemistry. Here the authors use quantum chemistry calculations and multi-coincidence mass spectrometry to show that a size-dependent structural transition enhances the production of O 2 + from photoionized CO2 clusters. [ABSTRACT FROM AUTHOR]

Background: The mechanical response and damage mechanisms of heterogeneous cementitious materials result from the mechanical properties of their constituents at the mesoscale. Objective: In this study, a finite element based Digital Volume Correlation (FE-DVC) method with mechanical regularization tailored for heterogeneous materials was applied to study crack propagation in mortar. Methods: A realistic 3D mesh was built consistently with the actual microstructure based on high resolution X-ray tomography. A notched mesobeam was subjected to in situ three-point flexure. Results: The introduction of mechanical contrast in DVC analyses allowed the strain heterogeneities related to the underlying microstructure to be described and inelastic strain localization due to cracks to be captured. Furthermore, the relaxation of mechanical regularization in damaged elements improved the trustworthiness of displacement measurements. Conclusions: Estimations of crack opening displacements and characterization of the crack morphology were carried out, providing insights into the damage processes at the mesoscale. [ABSTRACT FROM AUTHOR]

One class of particularly active catalysts for the Propane Dehydrogenation (PDH) reaction are well-defined M(III) sites on amorphous SiO2. In the present work, we focus on evaluating the catalytic trends of the PDH for four M(III) single-sites (Cr, Mo, Ga and In) on a realistic amorphous model of SiO2 using density functional theory-based calculations and the energetic span model. We considered a catalytic pathway spanned by three reaction steps taking place on selected MIII–O pair of the SiO2 model: σ-bond metathesis of propane on a MIII–O bond to form M-propyl and O–H group, a β-H transfer step forming M–H and propene, and the H–H coupling step producing H2 and regenerating the initial M–O bond. With the application of the energetic span model, we found that the calculated catalytic activity for Ga and Cr is comparable to the ones reported at the experimental level, enabling us to benchmark the model and the methodology used. Furthermore, results suggest that both In(III) and Mo(III) on SiO2 are potential active catalysts for PDH, provided they can be synthesized and are stable under PDH reaction conditions. [ABSTRACT FROM AUTHOR]