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The main objective is to analyse gas flow dynamics in a Convergent-Divergent (CD) nozzle and predict its behaviour under various conditions. The model assumes adiabatic, impermeable walls with bidimensional, compressible, steady, subsonic, and turbulent flow. Conservation equations for mass, energy, and momentum form the basis of the mathematical model, which is solved using Reynolds-Averaged Navier-Stokes turbulent models including Standard k-e, Realizable k-e, Standard k-?, and Shear-Stress Transport k-?. Evaluation of these models across different Nozzle Pressure Ratios (NPR) shows that Shear-Stress Transport k-? correlates best with experimental data on static pressure. Three ANSYS products: DesignModeler, Meshing, and Fluent, are used for numerical simulation. The methodology reliably predicts phenomena such as flow separation, Mach disc formation, and nozzle exit regime, crucial for safe and efficient system operation.

To determine the usefulness of combining two methodologies (OSCE and escape room) in a scenario simulation to evaluate a subject, and determine the evaluation of the students of this experience. An observational cross-sectional study was carried out with students enrolled in a sexual and reproductive health-care course as a part of their nursing degree. The students had to solve four clinical cases based on the contents of the teaching practices of the subject by solving clues that led them to carry out procedures and techniques and provide care in scenario simulators. Students evaluated the experience using the GAMEX (Gameful Experience in Gamification) scale. Mean differences were estimated with their respective 95% confidence intervals. A total of 124 students participated. Of these, 63.7% (79) solved the clinical cases with their knowledge and skills. Most (80.6%, 100) students stated that they completely remembered and applied the knowledge of the topic during the game. Almost all (98.4%, 122) would recommend this experience. The dimensions with the best rating on the GAMEX scale were “fun”, with an average score of 4.7 points (0.49), followed by “critical thinking”, with 4.2 (0.59). Women presented statistically better scores than men (mean difference: 1.58; 95% CI: 0.55, 2.61). The OSCE combined with an escape room using scenario simulations may be a useful tool to evaluate the subject. In addition, the students were satisfied, had fun, and recommended the experience. This study was not registered.

This paper presents a case study on integrating Agile Systems Engineering methodologies in the preliminary design phase of satellite systems, focusing on the 3ColStar satellite mission. Through Model-Based Systems Engineering (MBSE), technical consistency was rigorously managed across various architectural documents, ensuring coherency and minimizing errors. Furthermore, the preliminary design was developed, with the implementation of the Arcadia Method, supported by the Capella modeling tool. This allowed the digitalization of the system, which was represented by models that contain requirements, architecture, and interfaces between the different parts of the system. At the same time, the preliminary design process was streamlined and completed within an accelerated time frame of 4 months, with weekly sprints driving progress based on the scrum methodology. This case study highlights the effectiveness of Agile Systems Engineering principles to improve the team communication accuracy, communication, and efficiency of satellite systems preliminary design, providing valuable insights for future missions.

The comeback of wheat stem rust in Europe, caused by Puccinia graminis f. sp. tritici, and the prevalence of the alternate (sexual) host in local areas have recently regained attention as a potential threat to European wheat production. The aim of this study was to investigate a potential epidemiological link between the aecia found on an indigenous barberry species and stem rust infections on nearby cereals and grasses. Aecial infections collected from Berberis vulgaris subsp. seroi were inoculated on a panel of susceptible genotypes of major cereal crop species. In total, 67 stem rust progeny isolates were recovered from wheat (51), barley (7), and rye (9), but none from oat, indicating the potential of barberry derived isolates to infect multiple cereals. Molecular genotyping of the progeny isolates and 20 cereal and grass stem rust samples collected at the same locations and year, revealed a clear genetic relatedness between the progeny isolated from barberry and the stem rust infections found on nearby cereal and grass hosts. Analysis of Molecular Variance indicated that variation between the stem rust populations accounted for only 1%. A Principal Components Analysis using the 62 detected multilocus genotypes also demonstrated a low degree of genetic variation among isolates belonging to the two stem rust populations. Lastly, pairwise comparisons based on fixation index (Fst), Nei’s genetic distances and number of effective migrants (Nm) revealed low genetic differentiation and high genetic exchange between the two populations. Our results demonstrated a direct epidemiological link and functionality of an indigenous barberry species as the sexual host of P. graminis in Spain, a factor that should be considered when designing future strategies to prevent stem rust in Europe and beyond.

Rye (Secale cereale L.) is an important cereal crop used for food, beverages, and feed, especially in North-Eastern Europe. While rye is generally more tolerant to biotic and abiotic stresses than other cereals, it still can be infected by several diseases, including scald caused by Rhynchosporium secalis. The aims of this study were to investigate the genetic architecture of scald resistance, to identify genetic markers associated with scald resistance, which could be used in breeding of hybrid rye and to develop a model for genomic prediction for scald resistance. Four datasets with records of scald resistance on a population of 251 hybrid winter rye lines grown in 2 years and at 3 locations were used for this study. Four genomic models were used to obtain variance components and heritabilities of scald resistance. All genomic models included additive genetic effects of the parental components of the hybrids and three of the models included additive-by-additive epistasis and/or dominance effects. All models showed moderate to high broad sense heritabilities in the range of 0.31 (SE 0.05) to 0.76 (0.02). The model without non-additive genetic effects and the model with dominance effects had moderate narrow sense heritabilities ranging from 0.24 (0.06) to 0.55 (0.08). None of the models detected significant non-additive genomic variances, likely due to a limited data size. A genome wide association study was conducted to identify markers associated with scald resistance in hybrid winter rye. In three datasets, the study identified a total of twelve markers as being significantly associated with scald resistance. Only one marker was associated with a major quantitative trait locus (QTL) influencing scald resistance. This marker explained 11-12% of the phenotypic variance in two locations. Evidence of genotype-by-environment interactions was found for scald resistance between one location and the other two locations, which suggested that scald resistance was influenced by different QTLs in different environments. Based on the results of the genomic prediction models and GWAS, scald resistance seems to be a quantitative trait controlled by many minor QTL and one major QTL, and to be influenced by genotype-by-environment interactions.

The use of commercial off-the-shelf (COTS) components in CubeSat design offers flexibility, scalability, reduced power budget, and reduced development time. For these reasons, many space missions have adopted COTS platforms, owing to their advantages and limitations. An electrical power system (EPS) is a critical subsystem of COTS platforms that must meet mission requirements for the satellite to operate and guarantee mission success, including support for the operation modes and meeting the required lifetime. However, EPS validation is necessary to identify EPS characteristics such as energy generation, storage, consumption, and management modes. The power budget is a crucial aspect in the validation, design, and correct selection of an EPS, which can reduce costs and ensure compliance with EPS requirements. In this paper, a method is proposed to validate the EPS characteristics of COTS platforms by analyzing the power budget according to mission specifications. The approach determines the power and energy for the operational modes and scenarios and evaluates the battery depth of discharge (DoD) and charge/discharge cycles. The effectiveness of the proposed method is demonstrated through a case study of the LEOPAR mission, a 3U CubeSat satellite. The results show that the EPS can meet the power demands of the satellite subsystems during the mission. Our method provides a systematic and easy-to-follow process for validating CubeSat satellite EPS and can significantly enhance the development process for these satellites. It also contributes to the small-satellite community by providing a valuable tool to ensure the success of CubeSat missions.

The increased emergence of cereal stem rust in southern and western Europe, caused by the pathogen Puccinia graminis, and the prevalence of alternate (sexual) host, Berberis species, have regained attention as the sexual host may serve as source of novel pathogen variability that may pose a threat to cereal supply. The main objective of the present study was to investigate the functional role of Berberis species in the current epidemiological situation of cereal stem rust in Europe. Surveys in 11 European countries were carried out from 2018 to 2020, where aecial infections from five barberry species were collected. Phylogenetic analysis of 121 single aecial clusters of diverse origin using the elongation factor 1-α gene indicated the presence of different special forms (aka formae speciales) of P. graminis adapted to different cereal and grass species. Inoculation studies using aecial clusters from Spain, United Kingdom, and Switzerland resulted in 533 stem rust isolates sampled from wheat, barley, rye, and oat, which confirmed the presence of multiple special forms of P. graminis. Microsatellite marker analysis of a subset of 192 sexually-derived isolates recovered on wheat, barley and rye from the three populations confirmed the generation of novel genetic diversity revealed by the detection of 135 multilocus genotypes. Discriminant analysis of principal components resulted in four genetic clusters, which grouped at both local and country level. Here, we demonstrated that a variety of Berberis species may serve as functional alternate hosts for cereal stem rust fungi and highlights the increased risks that the sexual cycle may pose to cereal production in Europe, which calls for new initiatives within rust surveillance, epidemiological research and resistance breeding.

The objective of this study was to investigate the re-emergence of a previously important crop pathogen in Europe, Puccinia graminis f.sp. tritici, causing wheat stem rust. The pathogen has been insignificant in Europe for more than 60 years, but since 2016 it has caused epidemics on both durum wheat and bread wheat in local areas in southern Europe, and additional outbreaks in Central- and West Europe. The prevalence of three distinct genotypes/races in many areas, Clade III-B (TTRTF), Clade IV-B (TKTTF) and Clade IV-F (TKKTF), suggested clonal reproduction and evolution by mutation within these. None of these genetic groups and races, which likely originated from exotic incursions, were detected in Europe prior to 2016. A fourth genetic group, Clade VIII, detected in Germany (2013), was observed in several years in Central- and East Europe. Tests of representative European wheat varieties with prevalent races revealed high level of susceptibility. In contrast, high diversity with respect to virulence and Simple Sequence Repeat (SSR) markers were detected in local populations on cereals and grasses in proximity to Berberis species in Spain and Sweden, indicating that the alternate host may return as functional component of the epidemiology of wheat stem rust in Europe. A geographically distant population from Omsk and Novosibirsk in western Siberia (Russia) also revealed high genetic diversity, but clearly different from current European populations. The presence of Sr31-virulence in multiple and highly diverse races in local populations in Spain and Siberia stress that virulence may emerge independently when large geographical areas and time spans are considered and that Sr31-virulence is not unique to Ug99. All isolates of the Spanish populations, collected from wheat, rye and grass species, were succesfully recovered on wheat, which underline the plasticity of host barriers within P. graminis. The study demonstrated successful alignment of two genotyping approaches and race phenotyping methodologies employed by different laboratories, which also allowed us to line up with previous European and international studies of wheat stem rust. Our results suggest new initiatives within disease surveillance, epidemiological research and resistance breeding to meet current and future challenges by wheat stem rust in Europe and beyond.

Abstract Background Obesity is a worldwide public health problem that demands significant attention. Several studies have found that maternal obesity has a negative effect on the duration of breastfeeding and delayed lactogenesis. The World Health Organization has classified Body Max Index (BMI) as normal weight (normoweight) (BMI:18.5–24.9), overweight (BMI:25–29.9), obesity grade I (30.0–34.9), obesity grade II (BMI: 35.0–39.9) and obesity grade III (BMI ≥ 40.0). The objective of this study is to describe the relationship between maternal BMI and breastfeeding rates, as well as breastfeeding-associated problems and discomfort in women assisted by the Spanish Health System. Methods To this end, a cross-sectional observational study aimed at women who have been mothers between 2013 and 2018 in Spain was developed. The data was collected through an online survey of 54 items that was distributed through lactation associations and postpartum support groups between March and June 2019. Five thousand eight hundred seventy one women answered the survey. In the data analysis, Crude Odds Ratios (OR) and Adjusted Odds Ratios (AOR) were calculated through a multivariate analysis through binary and multinomial regression. Results A linear relationship was observed between the highest BMI figures and the reduction of the probability of starting skin-to-skin contact (AOR for obesity type III of 0.51 [95% CI 0.32, 0.83]), breastfeeding in the first hour (AOR for obesity type III of 0.58 [95% CI 0.36, 0.94]), and exclusive breastfeeding to hospital discharge (AOR for obesity type III of 0.57 [95% CI 0.35, 0.94]), as compared to women with normoweight. Conclusions Women with higher BMI are less likely to develop successful breastfeeding than women with normoweight.

One of the main applications of small satellites is Earth observation. CubeSats and different kinds of nanosatellites usually form constellations that obtain images mainly using an optical payload. There is a massive amount of data generated by these satellites and a limited capacity of download due to volume and mass constraints that make it difficult to use high-speed communication systems and high-power systems. For this reason, it is important to develop satellites with the autonomy to process data on board. In this way, the limited communication channel can be used efficiently to download relevant images containing the required information. In this paper, a system for the satellite on-board processing of RGB images is proposed, which automatically detects the cloud coverage level to prioritize the images and effectively uses the download time and the mission operation center. The system implements a Convolutional Neural Network (CNN) on a Commercial off-the-Shelf (COTS) microcontroller that receives the image and returns the cloud level (priority). After training, the system was tested on a dataset of 100 images with an accuracy of 0.9 and it was also evaluated with CubeSat images to evaluate the performance of a different image sensor. This implementation contributes to the development of autonomous satellites with processing on board.

Wheat (Triticum aestivum L.) is one of the world’s staple food crops and one of the most devastating foliar diseases attacking wheat is powdery mildew (PM). In Denmark only a few specific fungicides are available for controlling PM and the use of resistant cultivars is often recommended. In this study, two Chinese wheat landraces and two synthetic hexaploid wheat lines were used as donors for creating four multi-parental populations with a total of 717 individual lines to identify new PM resistance genetic variants. These lines and the nine parental lines (including the elite cultivars used to create the populations) were genotyped using a 20 K Illumina SNP chip, which resulted in 8,902 segregating single nucleotide polymorphisms for assessment of the population structure and whole genome association study. The largest genetic difference among the lines was between the donors and the elite cultivars, the second largest genetic difference was between the different donors; a difference that was also reflected in differences between the four multi-parental populations. The 726 lines were phenotyped for PM resistance in 2017 and 2018. A high PM disease pressure was observed in both seasons, with severities ranging from 0 to >50%. Whole genome association studies for genetic variation in PM resistance in the populations revealed significant markers mapped to either chromosome 2A, B, or D in each of the four populations. However, linkage disequilibrium between these putative quantitative trait loci (QTL) were all above 0.80, probably representing a single QTL. A combined analysis of all the populations confirmed this result and the most associated marker explained 42% of the variation in PM resistance. This study gives both knowledge about the resistance as well as molecular tools and plant material that can be utilised in marker-assisted selection. Additionally, the four populations produced in this study are highly suitable for association studies of other traits than PM resistance.

Abstract Background As resistance to insecticides increases in disease vectors, it has become exceedingly important to monitor populations for susceptibility. Most studies of field populations of Aedes aegypti have largely characterized resistance patterns at the spatial scale of the city or country, which may not be completely informative given that insecticide application occurs at the scale of the house or city block. Phenotypic resistance to pyrethroids dominates in Ae. aegypti, and it has been partially explained by mutations in the voltage-gated sodium channel gene. Here, we assess community-level patterns of four knockdown resistance (kdr) haplotypes (C1534/I1016, F1534/I1016, C1534/V1016 and F1534/V1016) in Ae. aegypti in 24 randomly chosen city blocks from a city in Yucatán State, Mexico, during both the dry and wet season and over two years. Results Three of the four haplotypes, C1534/I1016, C1534/V1016 and F1534/V1016 were heterogeneous between city blocks at all four sampling time points, and the double mutant haplotype, C1534/I1016, showed a significant increase following the wet season. The F1534/I1016 haplotype was rarely detected, similar to other studies. However, when haplotype frequencies were aggregated to a coarser spatial scale, the differences in space and time were obscured. Conclusions Our results provide empirical evidence that the selection of kdr alleles is occurring at fine spatial scales, indicating that future studies should include this scale to better understand evolutionary processes of resistance in natural populations.

We investigated whether the recent worldwide epidemics of wheat yellow rust were driven by races of few clonal lineage(s) or populations of divergent races. Race phenotyping of 887 genetically diverse Puccinia striiformis isolates sampled in 35 countries during 2009–2015 revealed that these epidemics were often driven by races from few but highly divergent genetic lineages. PstS1 was predominant in North America; PstS2 in West Asia and North Africa; and both PstS1 and PstS2 in East Africa. PstS4 was prevalent in Northern Europe on triticale; PstS5 and PstS9 were prevalent in Central Asia; whereas PstS6 was prevalent in epidemics in East Africa. PstS7, PstS8 and PstS10 represented three genetic lineages prevalent in Europe. Races from other lineages were in low frequencies. Virulence to Yr9 and Yr27 was common in epidemics in Africa and Asia, while virulence to Yr17 and Yr32 were prevalent in Europe, corresponding to widely deployed resistance genes. The highest diversity was observed in South Asian populations, where frequent recombination has been reported, and no particular race was predominant in this area. The results are discussed in light of the role of invasions in shaping pathogen population across geographical regions. The results emphasized the lack of predictability of emergence of new races with high epidemic potential, which stresses the need for additional investments in population biology and surveillance activities of pathogens on global food crops, and assessments of disease vulnerability of host varieties prior to their deployment at larger scales.

Extracellular bacterial ribonucleases such as binase from Bacillus pumilus possess cytotoxic activity against tumor cells with a potential for clinical application. Moreover, they may induce activation of tumor-derived macrophages either into the M1-phenotype with well-documented functions in the regulation of the antitumor immune response or into M2-macrophages that may stimulate tumor growth, metastasis, and angiogenesis. In this study, binase or endogenous RNase1 (but not RNA or short oligonucleotides) stimulated the expression of activated NF-κB p65 subunit in macrophages. Since no changes in MyD88 and TRIF adaptor protein expression were observed, toll-like receptors may not be involved in RNase-related NF-κB pathway activation. In addition, short exposure (0.5 hr) to binase induced the release of cytokines such as IL-6, МСР-1, or TNF-α (but not IL-4 and IL-10), indicative for the polarization into antitumor M1-macrophages. Thus, we revealed increased expression of activated NF-κB p65 subunit in macrophages upon stimulation by binase and RNase1, but not RNA or short oligonucleotides.

Abstract Traditional approaches of forest classifications were based on tree species composition, but recently combine phenology and climate to characterise functional (cyclic and seasonal greenness) rather than structural or compositional components (phenoclusters). The objective was to compare the conservation value (capacity to support more native biodiversity) and provision of ecosystem services (ES) in different phenocluster categories of Nothofagus antarctica forests in Tierra del Fuego (Argentina). We used available models (ES, potential biodiversity) and ground-truth data of 145 stands, comparing phenocluster values using uni- and multivariate analyses. Conservation value and capacity to supply ES significantly varied among phenocluster categories: (i) cultural, regulating, and provisioning ES and potential biodiversity at landscape level, (ii) soil carbon and nitrogen, (iii) dominant height, crown cover, basal area, total volume, and domestic animal stock, and (iv) understory plant richness and cover at stand level. These differences are linked to the forest capacity to support more native biodiversity and ES. Besides, multivariate analyses supporting the split of this forest type into four phenocluster subtypes (coast, highland, ecotone with other types, and degraded or secondary forests). Our findings suggest the needs of specific management and conservation proposals, based on phenoclusters rather than forest types defined by tree canopy-cover composition.