Fungal xenosiderophores from mycobiota and diet promote Salmonella colonization of the inflamed gut

The fungal gut microbiota (mycobiota) has been implicated in diseases that disturb gut homeostasis. However, little is known about functional relationships between bacteria and fungi in the gut during infectious colitis. We investigated the role of fungal metabolites during infection with the intestinal pathogen Salmonella enterica serovar Typhimurium. We found that in the gut lumen, both the mycobiota and fungi present in the diet can be a source of siderophores, small molecules that scavenge iron from the host. The ability to use fungal siderophores, such as ferrichrome and coprogen, conferred a competitive growth advantage to Salmonella strains expressing the fungal siderophore receptors FhuA or FhuE in vitro and in a mouse model. Our study highlights the role of inter-kingdom cross-feeding between fungi and Salmonella, and elucidates a new function for the gut mycobiota, revealing the importance of these under-studied members of the gut ecosystem during bacterial infection.

Transcriptomic Analysis Reveals Competitive Growth Advantage of Non-pigmented Serratia marcescens Mutants

Serratia marcescens is a common bacterium well-known for the red secondary metabolite prodigiosin. However, color mutants have long been described. Non-pigmented strains can be found to exist both naturally and under laboratory conditions. It is unclear why S. marcescens loses prodigiosin synthesis capacity in certain conditions. In the present study, we find that the spontaneous color mutants arise within a few generations (about five passages) and rapidly replace the wild-type parent cells (about 24 passages), which indicates a growth advantage of the former. Although, the loss of prodigiosin synthesis genes (pigA-N) is frequently reported as the major reason for pigment deficiency, it was unexpected that the whole gene cluster is completely preserved in the different color morphotypes. Comparative transcriptomic analysis indicates a dramatic variation at the transcriptional level. Most of the pig genes are significantly downregulated in the color morphotypes which directly lead to prodigiosin dyssynthesis. Besides, the transcriptional changes of several other genes have been noticed, of which transcriptional regulators, membrane proteins, and nearly all type VI secretion system (T6SS) components are generally downregulated, while both amino acid metabolite and transport systems are activated. In addition, we delete the transcription regulator slyA to generate a non-pigmented mutant. The ΔslyA strain loses prodigiosin synthesis capacity, but has a higher cell density, and surprisingly enhances the virulence as an entomopathogen. These data indicate that S. marcescens shuts down several high-cost systems and activates the amino acid degradation and transport pathways at the transcriptional level to obtain extra resources, which provides new insights into the competitive growth advantage of bacterial spontaneous color mutants.

Vietnamese migrants are as tall as they want to be

Background Members of the same social group tent to have the same body height. Migrants tend to adjust in height to their host communities. Objectives Social-Economic-Political-Emotional (SEPE) factors influence growth. We hypothesized that Vietnamese young adult migrants in Germany (1) are taller than their parents, (2) are as tall as their German peers, and (3) are as tall as predicted by height expectation at age 13 years. Sample and Methods The study was conducted in 30 male and 54 female Vietnamese migrants (mean age 26.23 years. SD=4.96) in Germany in 2020. Information on age, sex, body height, school and education, job, height and ethnicity of best friend, migration history and cultural identification, parental height and education, and recalled information on their personal height expectations at age 13 years were obtained by questionnaire. The data were analyzed by St. Nicolas House Analysis (SNHA) and multiple regression. Results Vietnamese young adults are taller than their parents (females 3.85cm, males 7.44cm), but do not fully attain height of their German peers. The body height is positively associated with the height of best friend (p < 0.001), the height expectation at age 13 year (p < 0.001), and father height (p=0.001). Conclusion Body height of Vietnamese migrants in Germany reflects competitive growth and strategic growth adjustments. The magnitude of this intergenerational trend supports the concept that human growth depends on Social-Economic-Political-Emotional (SEPE) factors.

In situ regulation of microstructure and microwave-absorbing properties of FeSiAl through HNO3 oxidation

Wrapping insulation of coatings is effective for enhancing the microwave-absorbing properties (MAPs) of ferromagnetic absorbents (FMAs). However, the process is still limited by the low bonding strength with the matrix. Herein, an in situ regulation strategy based on the preparation of thin thickness and strong adhesion insulating layers through HNO3 oxidation was developed to address the limitations. The oxidation process of FeSiAl (FSA) powders was carried out by HNO3 following three main steps. First, the original oxide layer first reacted with HNO3 to form Fe3+ and Al3+. Second, the oxide layer composed of Al2O3 and Fe3O4 was preferentially formed due to the negative change in Gibbs free energy. Finally, the oxide and pigment-deposition layers were subjected to competitive growth and dissolution accompanied by the dissolution of Fe and Al atoms. Oxidation time up to 10 min resulted in the formation of a bilayer structure with a thickness of ∼50 nm on the FSA surface, as well as an outer layer crammed of Al(OH)3 and Fe(OH)3, and an inner layer containing mixed Fe2O3, Fe3O4, Al2O3, and SiO2. The MAPs of as-treated FSA achieved minimum reflection loss (RL) of −25.90 dB at 13.36 GHz, as well as absorption bandwidth of 5.61 GHz (RL < −10 dB) at 10.13–15.74 GHz and thickness of 2.5 mm. In sum, the developed route looks promising for the preparation of high-performance FMAs.

Morphological and Molecular Analysis of Fungal Species Associated with Blast and Brown Spot Diseases of Oryzae sativa

Fungal diseases; blast, and brown spot in rice incur severe yield losses worldwide. Blast is caused by Magnaporthe oryzae, while Bipolaris oryzae is reported as the main causal organism of brown spot. Both diseases cause leaf lesions which are difficult to be differentiated by symptomatology until the late stages. Early detection and differentiation of the lesions would help the adoption of disease management strategies specific to the pathogen and will prevent the native impact on the quality and quantity of rice yields. This study was conducted in the Northern Province of Sri Lanka over five consecutive rice cultivating seasons to characterize the causal fungi of rice blast and brown spot diseases by morphological and molecular means and to develop a visual guide to differentiate the two diseases. Disease incidence was recorded in 114 fields from 2017 to 2019, and fungal isolates associated with lesions of both the diseases were cultured and subjected to morphological and molecular characterization. Competitive growth interaction between M. oryzae and the more common individual fungal isolates of the brown spot lesions, was evaluated. Fungal metagenomics analysis was conducted for the fungal spp. isolated from brown spot lesions. A suppression of blast accompanied by an increased incidence of brown spot disease was observed during the study period. M. oryzae was confirmed to be the causal organism of the blast while over 20 species of fungi were identified to be associated with brown spot lesions through morphological, molecular studies, and metagenomics analyses. Fungal ITS region sequencing revealed considerable genetic variation in the highly conserved region of DNA sequences of blast and brown spot fungal isolates. B. oryzae, Curvularia, and Microdochium species were commonly isolated from brown spot lesions. In vitro competitive growth interaction among the fungal isolates revealed growth suppression of M. oryzae by the fungal isolates associated with the brown spot lesions. Similarly, it can be speculated that the abundance and severity of blast in the field may have an influence on brown spot associated fungi. A simple visual guide was developed to differentiate blast and brown spot lesions. The findings would be highly useful in the timely management of these major fungal diseases affecting rice.

Multi-phase field simulation of competitive grain growth for directional solidification

The multi-phase field model of grain competitive growth during directional solidification of alloy was established, solving multi-phase field models for thin interface layer thickness conditions, grain boundary evolution and grain elimination during the competitive growth of SCN-0.24wt% camphor model alloy bi-crystals were investigated, the effects of different crystal orientations and pulling velocities on grain boundary microstructure evolution were quantitatively analyzed. The results show that in the competitive growth of convergent bi-crystals, when favorably oriented dendrites are in the same direction as the heat flow and the pulling speed is too large, the orientation angle of the bi-crystal from small to large is the normal elimination phenomenon of the favorably oriented dendrite blocking the unfavorably oriented dendrite, and the grain boundary is along the growth direction of the favorably oriented dendrite, and when the pulling speed becomes small, the grain boundary shows the anomalous elimination phenomenon of the unfavorably oriented dendrite eliminating the favorably oriented dendrite. In the process of competitive growth of divergent bi-crystal, when the growth direction of favorably oriented dendrites is the same as the heat flow direction and the orientation angle of unfavorably oriented grains is small, the frequency of new spindles of favorably oriented grains is significantly higher than that of unfavorably oriented grains, and as the orientation angle of unfavorably oriented dendrites becomes larger, the unfavorably oriented grains are more likely to have stable secondary dendritic arms, which in turn develop new primary dendritic arms to occupy the liquid phase grain boundary space, but the grain boundary direction is still parallel to favorably oriented dendrites. In addition, the tertiary dendritic arms on the developed secondary dendritic arms may also be blocked by the surrounding lateral branches from further developing into nascent main axes, this blocking of the tertiary dendritic arms has a random nature, which can have an impact on the generation of nascent primary main axes in the grain boundaries.

DNMT3A knockouts in human iPSCs prevent de novo DNA methylation and reveal growth advantage during hematopoietic differentiation

DNA methyltransferase 3A (DNMT3A) is a frequently mutated gene in many hematological malignancies, indicating that it may be essential for hematopoietic differentiation. Here, we addressed the functional relevance of DNMT3A for differentiation of human induced pluripotent stem cells (iPSCs) by knocking out exon 2, 19, or 23. Exon 19-/- and 23-/- lines revealed absence of almost the entire de novo DNA methylation during mesenchymal and hematopoietic differentiation. Yet, differentiation was only slightly reduced in exon 19-/- and increased in exon 23-/- lines, whereas there was no significant impact on gene expression in hematopoietic progenitors (iHPCs). Notably, DNMT3A-/- iHPCs recapitulate some DNA methylation differences of acute myeloid leukemia with DNMT3A mutations. Furthermore, multicolor genetic barcoding revealed competitive growth advantage of exon 23-/- iHPCs. Our results demonstrate that de novo DNA methylation during hematopoietic differentiation of iPSCs is almost entirely dependent on DNMT3A and exon 23-/- iHPCs even gained growth advantage.

Investigation on Optimal Ta/Cr Ratio of a Single Crystal Ni-Base Superalloy in View of the Isothermal Oxidation Behavior

The relative content of strengthening element tantalum (Ta) and oxidation-resistant element chromium (Cr) is an essential value for superalloys to obtain an excellent combination of oxidation resistance and mechanical properties. In the present paper, the isothermal oxidation behavior of several single crystal Ni-base superalloys with different Ta/Cr (wt. %, similarly hereinafter) ratios at 1000 °C in static air has been systematically investigated to explore the optimal Ta/Cr for excellent oxidation resistance. A detailed microstructure study using X-ray diffraction (XRD), scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS) and an electro-probe microanalyzer (EPMA) was performed to reveal the oxidation products and mechanisms. For all alloys, a three-layer structured scale consisting of an outer (Cr, Al, Ti, Ni, Ta)-O layer, an inner Al2O3 layer and an inner nitride layer was formed. As Ta/Cr increased, the amounts of Ta-containing products, cracks, holes and inner nitride increased. Meanwhile, the completeness of the Al2O3 layer got worse. It was shown that if Ta/Cr ≤ 0.5, Ta increased the growth rate of Cr2O3 via the doping effect induced by Ta cations. If Ta/Cr > 0.5, Ta reduced the completeness of Cr2O3 through competitive growth of Ta2O5 and Cr2O3. A good oxidation performance can be expected with the value Ta/Cr ≤ 0.5.

Sowing Mixtures of Native Plant Species: Are There Any Differences between Hydroseeding and Regular Seeding?

Hydroseeding is a convenient, low-cost way to plant seeds. Traditionally, fast-growing commercial species that are cheap to obtain are preferred in hydroseeding, while native species have limited use. Nowadays, the use of native species is often desired in revegetation projects. However, there is a paucity of information about hydroseeding native species in Northern areas of Europe. Therefore, we aimed to determine whether hydroseeding has any effects on native plant cover formation, species richness and abundance, the development of plant morphological features, or aboveground biomass. A total of 40 native plant species in Lithuania were sowed using hydroseeding and regular seeding. The experimental plots were assessed for two years. The results show a relatively small and short positive effect of hydroseeding on plant cover formation. No significant differences were found in species richness between the sowing treatments. However, a comparison of species composition revealed significant differences between the sowing treatments that were more associated with species abundance than species diversity. Hydroseeding was favoured by legume species, such as Onobrychis viciifolia, Ononis arvensis, Lotus corniculatus, and Trifolium medium, while Festuca rubra favoured the regular seeding treatment. Overall, our findings emphasize that legume species that display more competitive growth traits should be included in the seed mixture in lower proportions when hydroseeding is applied.

Influence of Access To Finance On The Competitive Growth of SMEs in Lesotho.

Background: Access to finance is identified as one of the biggest problems faced by Small and Medium-Sized Enterprises (SMEs) in most developing economies. Consequently, access to finance has been identified as a dominant constraint facing the SMEs sector in Lesotho. This paper established the factors of access to finance that influence the competitive growth of the SME sector in Lesotho. The factors addressed include financial information access, bank and business support services, the structure of banks and collateral requirements by the financial sector. Findings: The results from our analysis indicated that there is a relationship between independent variables of financial information access, Bank and business support service, the structure of banks and the collateral requirement by commercial banks and such influence SMEs capacity to attain competitive growth in Lesotho. In addition, the results indicated that Basotho entrepreneurs and managers see the predictors as critical factors of access to finance that constrained most enterprises access to needed credit from banks and such influence SMEs capacity to attain competitive growth in Lesotho. Conclusions: The study concludes that access to finance significantly affect the competitive growth of SMEs in Lesotho. Thus, this study suggests that several specific and harmonized financial policy actions are needed in the Lesotho financial market to identify enabling policy that ease enterprises access to adequate funding programs. These funding programs should target improved financial schemes that are coordinated, competitive and directed towards SMEs access to finance; harmonized credit policy which guarantees a win-win for SMEs loan applicants and the financial market operators.