Abundant Species Research Articles

Tuning the Metal-Support Interaction by Modulating CeO2 Oxygen Vacancies to Enhance the Toluene Oxidation Activity of Pt/CeO2 Catalysts.

In this research, a range of Pt/CeO2 catalysts featuring varying Pt-O-Ce bond contents were developed by modulating the oxygen vacancies of the CeO2 support for toluene abatement. The Pt/CeO2-HA catalyst generated a maximum quantity of Pt-O-Ce bonds (possessed the strongest metal-support interaction), as evidenced by the visible Raman results, which demonstrated outstanding toluene catalytic performance. Additionally, the UV Raman results revealed that the strong metal-support interaction stimulated a substantial increase in oxygen vacancies, which could facilitate the activation of gaseous oxygen to generate abundant reactive oxygen species accumulated on the Pt/CeO2-HA catalyst surface, a conclusion supported by the H2-TPR, XPS, and toluene-TPSR results. Furthermore, the results from quasi-in situ XPS, in situ DRIFTS, and DFT indicated that the Pt/CeO2-HA catalyst with a strong metal-support interaction led to improved mobility of reactive oxygen species and lower oxygen activation energies, which could transfer a large number of activated reactive oxygen species to the reaction interface to participate in the toluene oxidation, resulting in the relatively superior catalytic performance. The approach of tuning the metal-support interaction of catalysts offers a promising avenue to develop highly active catalysts for toluene degradation.

Influence of the dietary contribution of terrestrial insects to the condition factor of bleak Alburnus alburnus in a highly polluted lowland river.

Bleak Alburnus alburnus is a highly abundant but understudied fish species, and we know little about the trophic ecology of populations inhabiting rivers in central Europe. From an ecosystem perspective, this fish species is interesting as it is known to feed on surface insects, thereby linking the terrestrial with the aquatic habitat. In a previous study, we demonstrated that this flux is intensified, and dietary contribution of terrestrial insects is higher in fish inhabiting sections of the Spree River, Germany, that are polluted from iron oxides occurring from former lignite mining activities, and thus are characterized by lower abundances of aquatic insects. As terrestrial insects can be considered as food of lower quality (measured as long-chained polyunsaturated fatty acids, n-3 LC-PUFAs) compared to aquatic prey, it is reasonable to assume that the higher contribution of terrestrial insects is related to a lower body condition in fish. In this study, we explore the trophic ecology of riverine A. alburnus and their fitness consequences of feeding on terrestrial insects. We therefore modeled a terrestrial index from stable isotopes of hydrogen (δ2H) measured in the A. alburnus muscle tissue and compared individuals caught in locations upstream of a dam that were greatly influenced by iron oxides, with individuals caught in sections located downstream of a dam where passive remediation technologies are applied. The terrestrial index was significantly higher in A. alburnus caught in locations at high-iron concentrations, characterized by low abundances of aquatic prey, compared to A. alburnus caught in unpolluted habitats at low-iron concentrations. In contradiction to our hypothesis, the terrestrial index had no significant effect on the body condition of A. alburnus (measured as Fulton's condition factor K) in the sections downstream of the dam (i.e., at low-iron concentrations) and a significant positive, albeit weak, effect in sections upstream of the dam (i.e., at high-iron concentrations). However, the condition factor was generally lower in the high-iron section, potentially related to more direct effects of the iron oxide. We conclude that in A. alburnus, terrestrial insects can be considered as the less-favored food, unless the fish occur in environments where the aquatic food is of limited availability. Further research is needed to evaluate the direct and indirect effects, including the internal n-3 LC-PUFA synthesis as an adaption toward low-quality terrestrial prey on the fitness consequences of A. alburnus.

Non-negligible secondary contribution to brown carbon in autumn and winter: inspiration from particulate nitrated and oxygenated aromatic compounds in urban Beijing

Abstract. Nitrated aromatic compounds (NACs) and oxygenated derivatives of polycyclic aromatic hydrocarbons (OPAHs) play vital roles within brown carbon (BrC), influencing both climate dynamics and human health to a certain degree. The concentrations of these drug classes were analyzed in PM2.5 from an urban area in Beijing during the autumn and winter of 2017 and 2018. There were four heavy haze episodes during the campaign, two of which happened prior to heating and the other two during heating. During the entire course of sampling, the mean total concentrations of the nine NACs and the eight OPAHs were 1.2–263 and 2.1–234 ng m−3, respectively. The concentrations of both NACs and OPAHs were approximately 2–3 times higher in the heating period than before heating. For NACs, the relative molecular composition did not change significantly before and during heating, with 4-nitrocatechol and 4-nitrophenol demonstrating the highest abundance. For OPAHs, 1-naphthaldehyde was the most abundant species before and during heating, while the relative proportion of anthraquinone increased by more than twice, from 13 % before heating to 31 % during the heating. In Beijing's urban area during autumn and winter, significant sources of NACs and OPAHs have been traced back to automobile emissions and biomass burning activities. Interestingly, it was observed that the contribution from coal combustion increased notably during heating. It is worth noting that the secondary generation of BrC was important throughout the whole sampling period, which was manifested by the photochemical reaction before heating and the aqueous reaction during heating. It was further found that the haze in autumn and winter was nitrate-driven before heating and secondary organic carbon (SOC)-driven during heating, and the secondary formation of BrC increased significantly in pollution events, particularly during heating.

Comprehensive systematic review and meta-analysis of microplastic prevalence and abundance in freshwater fish species: the effect of fish species habitat, feeding behavior, and Fulton’s condition factor

Comprehensive systematic review and meta-analysis of microplastic prevalence and abundance in freshwater fish species: the effect of fish species habitat, feeding behavior, and Fulton’s condition factor

Gut microbiome shifts in people with type 1 diabetes are associated with glycaemic control: an INNODIA study.

The gut microbiome is implicated in the disease process leading to clinical type 1 diabetes, but less is known about potential changes in the gut microbiome after the diagnosis of type 1 diabetes and implications in glucose homeostasis. We aimed to analyse potential associations between the gut microbiome composition and clinical and laboratory data during a 2 year follow-up of people with newly diagnosed type 1 diabetes, recruited to the Innovative approaches to understanding and arresting type 1 diabetes (INNODIA) study. In addition, we analysed the microbiome composition in initially unaffected family members, who progressed to clinical type 1 diabetes during or after their follow-up for 4 years. We characterised the gut microbiome composition of 98 individuals with newly diagnosed type 1 diabetes (ND cohort) and 194 autoantibody-positive unaffected family members (UFM cohort), representing a subgroup of the INNODIA Natural History Study, using metagenomic sequencing. Participants from the ND cohort attended study visits within 6 weeks from the diagnosis and 3, 6, 12 and 24 months later for stool sample collection and laboratory tests (HbA1c, C-peptide, diabetes-associated autoantibodies). Participants from the UFM cohort were assessed at baseline and 6, 12, 18, 24 and 36 months later. We observed a longitudinal increase in 21 bacterial species in the ND cohort but not in the UFM cohort. The relative abundance of Faecalibacterium prausnitzii was inversely associated with the HbA1c levels at diagnosis (p=0.0019). The rate of the subsequent disease progression in the ND cohort, as assessed by change in HbA1c, C-peptide levels and insulin dose, was associated with the abundance of several bacterial species. Individuals with rapid decrease in C-peptide levels in the ND cohort had the lowest gut microbiome diversity. Nineteen individuals who were diagnosed with type 1 diabetes in the UFM cohort had increased abundance of Sutterella sp. KLE1602 compared with the undiagnosed UFM individuals (p=1.2 × 10-4). Our data revealed associations between the gut microbiome composition and the disease progression in individuals with recent-onset type 1 diabetes. Future mechanistic studies as well as animal studies and human trials are needed to further validate the significance and causality of these associations.

Evaluation of shrimp-associated species in abandoned ponds in Mati City, Philippines

This study aimed to identify, characterize, and evaluate the biodiversity of shrimp-associated species in abandoned shrimp ponds, specifically assessing the trophic levels of bycatch species in Barangay Dahican, Mati City. Using a scoop net, researchers collected macrobenthic samples from Maitum, Lahusan, and Butuasan, finding 1,528 individuals with varying species compositions namely: Oreochromis niloticus (Nile tilapia), Coenobita cavipes (Land hermit crab), Canarium labiatum (Plicate conch), Rochia nilotica (Commercial top), Clithon oualaniense (Guamanian nerite), Cerithium coralium (Coral cerith), and Callinectes sapidus (Blue crab). Cerithium coralium was the most abundant species with 70% relative abundance, followed by Clithon oualaniense, with 29%. In contrast, the least abundant species were the Oreochromis niloticus and Canarium labiatum, with 1% relative abundance. Moreover, biodiversity indices revealed that Lahusan 1 (H' = 0.731; D=0.46) and Butuasan (H' = 0.714; D = 0.5) had higher biodiversity, whereas Lahusan 2 had the lowest (H' = 0.318; D = 0.15). In contrast, Lahusan 2 appeared to be the least diverse (H' = 0.318; D = 0.15). There were significant differences in terms of species abundance (df = 6, MS = 34.18, F = 6.02, P = 0.000) and none in terms of site locations (df = 3, MS = 18.71, F=2.08, P= 0.188). The study results showed that these associated species were mainly benthic and came from the nearby environment. Providing good management for the abandoned shrimp ponds in the area could mean reverting them to their original state to provide a habitat for other organisms.

Climate change impacts on small pelagic fish distribution in Northwest Africa: trends, shifts, and risk for food security

Climate change is recognised to lead to spatial shifts in the distribution of small pelagic fish, likely by altering their environmental optima. Fish supply along the Northwest African coast is significant at both socio-economic and cultural levels. Evaluating the impacts of climatic change on small pelagic fish is a challenge and of serious concern in the context of shared stock management. Evaluating the impact of climate change on the distribution of small pelagic fish, a trend analysis was conducted using data from 2363 trawl samplings and 170,000 km of acoustics sea surveys. Strong warming is reported across the Southern Canary Current Large Marine Ecosystem (CCLME), extending from Morocco to Senegal. Over 34 years, several trends emerged, with the southern CCLME experiencing increases in both wind speed and upwelling intensity, particularly where the coastal upwelling was already the strongest. Despite upwelling-induced cooling mechanisms, sea surface temperature (SST) increased in most areas, indicating the complex interplay of climatic-related stressors in shaping the marine ecosystem. Concomitant northward shifts in the distribution of small pelagic species were attributed to long-term warming trends in SST and a decrease in marine productivity in the south. The abundance of Sardinella aurita, the most abundant species along the coast, has increased in the subtropics and fallen in the intertropical region. Spatial shifts in biomass were observed for other exploited small pelagic species, similar to those recorded for surface isotherms. An intensification in upwelling intensity within the northern and central regions of the system is documented without a change in marine primary productivity. In contrast, upwelling intensity is stable in the southern region, while there is a decline in primary productivity. These environmental differences affected several small pelagic species across national boundaries. This adds a new threat to these recently overexploited fish stocks, making sustainable management more difficult. Such changes must motivate common regional policy considerations for food security and sovereignty in all West African countries sharing the same stocks.

Are physiological and ecosystem-level tipping points caused by ocean acidification? A critical evaluation

Abstract. Ocean acidification (OA) is predicted to cause profound shifts in many marine ecosystems by impairing the ability of calcareous taxa to calcify and grow and by influencing the physiology of many others. In both calcifying and non-calcifying taxa, ocean acidification could further impair the ability of marine life to regulate internal pH and thus metabolic function and/or behaviour. Identifying tipping points at which these effects will occur for different taxa due to the direct impacts of ocean acidification on organism physiology is difficult because they have not adequately been determined for most taxa nor for ecosystems at higher levels. This is due to the presence of both resistant and sensitive species within most taxa. However, calcifying taxa such as coralline algae, corals, molluscs, and sea urchins appear to be most sensitive to ocean acidification. Conversely, non-calcareous seaweeds, seagrasses, diatoms, cephalopods, and fish tend to be more resistant or even benefit from the direct effects of ocean acidification, though the effects of ocean acidification are more subtle for these taxa. While physiological tipping points of the effects of ocean acidification either do not exist or are not well defined, their direct effects on organism physiology will have flow-on indirect effects. These indirect effects will cause ecological tipping points in the future through changes in competition, herbivory, and predation. Evidence for indirect effects and ecological change is mostly taken from benthic ecosystems in warm temperate–tropical locations in situ that have elevated CO2. Species abundances at these locations indicate a shift away from calcifying taxa and towards non-calcareous taxa at high-CO2 concentrations. For example, lower abundance of corals and coralline algae and higher covers of non-calcareous macroalgae, often turfing species, are often found at elevated CO2. However, there are some locations where only minor changes or no detectable changes occur. Where ecological tipping points do occur, it is usually at locations with naturally elevated mean pCO2 concentrations of 500 µatm or more, which also corresponds to just under that concentration where the direct physiological impacts of ocean acidification are detectable in the most sensitive taxa in laboratory research (coralline algae and corals). Collectively, the available data support the concern that ocean acidification will most likely cause ecological change in the near future in most benthic marine ecosystems, with tipping points in some ecosystems as low as 500 µatm pCO2. However, further research is required to more adequately quantify and model the extent of these impacts in order to accurately project future marine ecosystem tipping points under ocean acidification.

Does Exposure to Burning and Heated Tobacco Affect the Abundance of Perio-Pathogenic Species in the Subgingival Biofilm?

This study investigated the impact of tobacco exposure, specifically through heating and burning, on periodontopathogens in the subgingival microbiome among clinically healthy individuals and those diagnosed with periodontitis. The sample comprised 66 subjects (26–56 years, median 38 yrs; 64% females) classified as non-smokers, classic cigarette smokers, and tobacco heating system (THS) smokers (each N = 22). Full-mouth periodontal examination was performed, and 330 paper-point samples from periodontal pockets were collected. Next-generation sequencing of 16S rRNA genes was conducted to identify the composition of subgingival microbiome. Periodontitis prevalence among the groups was ranked as THS (41%) < non-smokers (44%) < cigarette smokers (68%), without statistically significant differences between the groups. The number of perio-pathogenic species was higher in subjects with periodontitis compared to those without (median 7 vs. 6 species; p = 0.005) but without significant differences between exposure groups: non-smokers (6) = smokers (6) < THS (6.5). When combining exposure and periodontal status, each smoker group had more perio-pathogenic species than non-smokers: non-smokers without periodontitis (5) < smokers without periodontitis (5.5) < THS without periodontitis (6); non-smokers with periodontitis (6.5) < THS with periodontitis (7) = smokers with periodontitis (7). Multiple linear regression indicated periodontitis as the sole predictor of perio-pathogenic species quantity, irrespective of the type of tobacco consumption, sex, age, or oral hygiene (R2 = 0.163; p = 0.005). In conclusion, the quantity of perio-pathogenic species in the subgingival microbiome was more influenced by periodontitis than by exposure to tobacco smoke, regardless of whether it was heated or burned.

The response of epibenthic molluscan assemblages associated with Mytilus galloprovincialis beds to natural- and human-induced changes: Structure and small-scale spatiotemporal variability

Mussel beds are species-rich and diversified biogenic habitats for associated assemblages, playing important ecological roles and contributing significantly to local littoral invertebrate biodiversity. The community structure and seasonal patterns of molluscan assemblages associated with rocky-intertidal mussel Mytilus galloprovincialis beds along NW Atlantic coast of Morocco were investigated. Sampling was conducted at reference and contaminated stations in three distant coastal areas over a 4-season sampling period (between August 2018 and May 2019). We tested the hypothesis that the biogenic mussel habitats in areas experiencing different environmental conditions along the shore would support different associated molluscan assemblages under human-induced and natural changes at small spatial and temporal scales. A total of 6371 specimens comprising 28 taxa were identified and encompassing four trophic groups (carnivores, detritivores/deposivores, micrograzers and suspensivores). Micrograzers predominated, followed by carnivores, with gastropods being the numerically dominant taxa accounting for 79 % of total abundance. Steromphala pennanti emerged as the most abundant and frequent species, across almost all seasons and stations contributing to 31 % of total abundance. Significant seasonal variations were observed in species richness and Shannon-Wiener’s index (ANOVA, p<0.05), with the highest values recorded at the most polluted stations during cold/wet periods, and the lowest at the cleanest stations during hot/warm periods. Furthermore, the ANOVA analyses unveiled a significant spatiotemporal variation in abundance, emphasizing the dynamic nature of molluscan assemblages in response to environmental conditions and seasonal changes. The multivariate structure of associated molluscan assemblages (PERMANOVA analysis) differed significantly among stations and seasons, highlighting clear geographical and seasonal effects. Gastropod species, including Acanthochitona fascicularis, Lepidochitona cinerea, Nucella lapillus, Patella ulyssiponensis, P. vulgata, Phorcus lineatus, P. sauciatus, and Steromphala pennanti, were identified as the most contributive species to the dissimilarity of molluscan assemblage structure among stations throughout seasons (SIMPER analysis). Based on the canonical correspondence analysis results, salinity, water temperature, nutrient concentrations, sediment granulometry and total organic matter were identified as the key factors driving changes in the molluscan community structure. This study underscores the ecological importance of habitat-forming mussels as ecosystem engineers and biodiversity enhancers in shallow coastal waters along the Moroccan Atlantic coast.

Cooperative growth in microbial communities is a driver of multistability

Microbial communities often exhibit more than one possible stable composition for the same set of external conditions. In the human microbiome, these persistent changes in species composition and abundance are associated with health and disease states, but the drivers of these alternative stable states remain unclear. Here we experimentally demonstrate that a cross-kingdom community, composed of six species relevant to the respiratory tract, displays four alternative stable states each dominated by a different species. In pairwise coculture, we observe widespread bistability among species pairs, providing a natural origin for the multistability of the full community. In contrast with the common association between bistability and antagonism, experiments reveal many positive interactions within and between community members. We find that multiple species display cooperative growth, and modeling predicts that this could drive the observed multistability within the community as well as non-canonical pairwise outcomes. A biochemical screening reveals that glutamate either reduces or eliminates cooperativity in the growth of several species, and we confirm that such supplementation reduces the extent of bistability across pairs and reduces multistability in the full community. Our findings provide a mechanistic explanation of how cooperative growth rather than competitive interactions can underlie multistability in microbial communities.

Phlebotomine sand flies (Diptera: Psychodidae, Phlebotominae): Diversity of potential Leishmania vectors in northern Colombia

Phlebotomine sand flies are critical vectors of Leishmania parasites, impacting public health significantly. This study focused on assessing the diversity of sand flies in a rural area of El Carmen de Bolívar Municipality, northern Colombia, employing rarefaction curves and Hill numbers to understand potential vector communities and inform environmental management. From January 2018 to April 2019 (five samplings), sand flies were collected using CDC light traps with blue LED in domestic/peridomestic/sylvatic ecotopes, identifying species per Young and Duncan (1994) and Galati (2003). Hill numbers provided diversity estimates across samples, while Principal Component Analysis correlated with environmental factors with phlebotomine species presence and abundance. 8,784 phlebotomine individuals were collected; 56.4 % females and 43.6% males (ratio 3:2). These individuals belonged to eight species: Pintomyia evansi, Psychodopygus panamensis, Lutzomyia gomezi, Micropygomyia cayennensis, Evandromyia dubitans, Psathyromyia aclydifera, Pintomyia serrana, and Pintomyia rangeliana; with Pi. evansi being the most abundant species (74.39 %; 6,530 exemplars). The ANOVA showed no significant differences between phlebotomine sand flies abundances across ecotopes (p = 0.018). Species of epidemiological relevance as Pi. evansi and Lu. gomezi not show a positive correlation with environmental variables evaluated, only Ps. panamensis was positively correlated with precipitation. However, the study emphasizes the need for a continuous sand fly monitoring and research to enhance leishmaniasis control strategies, highlighting the necessity to expand knowledge on phlebotomine diversity and environmental interactions to understand vector ecology and disease dynamics better.

Mosquito Species Diversity and Abundance Patterns in Plots with Contrasting Land Use and Land Cover in Bloomington, Indiana.

Land use and land cover (LULC) gradients are associated with differences in mosquito species composition and the entomological risk of mosquito-borne disease. Here, we present results from a season-long study of mosquito species richness and abundance with samples collected at 9 locations from 2 plots with contrasting LULC, an urban farm and a forest preserve, in Bloomington, IN, a city in the midwestern USA. With a total sampling effort of 234 trap-nights, we collected 703 mosquitoes from 9 genera and 21 species. On the farm, we collected 15 species (285 mosquitoes). In the preserve, we collected 19 species (418 mosquitoes). Thirteen species were common in both study plots, 2 were exclusive to the farm, and 6 were exclusive to the forest preserve. In both plots, we collected Aedes albopictus and Ae. japonicus. In the farm, the most common mosquito species were Culex restuans/Cx. pipiens and Coquillettidia perturbans. In the preserve, Ae. japonicus and Ae. triseriatus were the 2 most common mosquito species. Time series analysis suggests that weather factors differentially affected mosquito species richness and mosquito abundance in the plots. Temperature, relative humidity (RH), and precipitation were positively associated with richness and abundance at the farm, while increases in the SD of RH decreased both richness and abundance at the preserve. Our results highlight the importance that LULC has for mosquito species diversity and abundance and confirm the presence of Ae. albopictus and Ae. japonicus in southwestern Indiana.

Host preference patterns in domestic and wild settings: Insights into Anopheles feeding behavior.

The adaptation of Anopheles malaria vectors to domestic settings is directly linked to their ability to feed on humans. The strength of this species-habitat association is unequal across the species within the genus, with the major vectors being particularly dependent on humans. However, our understanding of how blood-feeding behavior interacts with and adapts to environmental settings, including the presence of humans, remains limited. Using a field-based approach, we first investigated Anopheles community structure and feeding behavior patterns in domestic and sylvatic settings in La Lopé National Park in Gabon, Central Africa. We characterized the preference indices using a dual-host choice sampling approach across mosquito species, habitats, and seasons. We then quantified the plastic biting behavior of mosquito species in each habitat. We collected individuals from 16 Anopheles species that exhibited significant differences in species composition and abundance between sylvatic and domestic settings. The host-seeking behavior also varied among the seven most abundant species. The general attractiveness to each host, human or animal, remained relatively constant for each species, but with significant variations between habitats across species. These variations, to more generalist and to more anthropophilic behavior, were related to seasonal changes and distance from the village, respectively. Finally, we pointed out that the host choice of major malaria vectors changed in the absence of humans, revealing a plastic feeding behavior of these species. This study highlights the effect of humans on Anopheles distribution and feeding evolution. The characterization of feeding behavior in wild and domestic settings provides opportunities to better understand the interplay between genetic determinants of host preference and ecological factors. Our findings suggest that protected areas may offer alternative thriving conditions to major malaria vectors.

Mites associated with açaí palm trees (Euterpe oleracea: Arecaceae) in native and cultivated areas of the state of Pará (Eastern Amazon, Brazil).

The objective was to quantify and analyze the diversity of mites associated with native and cultivated açaí palms crops, as well as their distribution in the dry and rainy seasons in the municipalities of Bragança and Augusto Corrêa, state of Pará. Rarefaction curves were generated for diversity values using the statistical programming language R, rarefaction curves for estimates of richness and equitability, and analysis of variance with permutations. A total of 2069 mites from 28 families were sampled, being most representative Phytoseiidae (32.4%), Phytoptidae (13%), Cunaxidae (7.7%), Tetranychidae (5.6%) and Tydeidae (4.9%). Among predators, the most abundant species were Amblyseius sp. 1, Armascirus amazoniensis Wurlitzer & Silva, Iphiseiodes zuluagai Denmark & Muma, Scutopalus tomentosus Rocha, Skvarla & Ferla, and the phytophagous mites Acaphyllisa sp., Davisella sp., Oligonychus sp. and Retracus johnstoni Keifer. In the rainy season, more mites were sampled (n = 1176) than in the dry season (n = 893). The greatest richness was observed in the dry period (73 species) and diversity was also greater in this period. In the municipality of Bragança there was greater richness (78 species) and the cultivated açaí trees had greater acarine abundance (74.7%) than the native ones. However, natives had slightly higher wealth (6%) than those cultivated. The diversity and richness of predatory mites show the potential of the Amazon biome to be used in applied biological control.

A 3D picture of moist-convection inhibition in hydrogen-rich atmospheres: Implications for K2-18 b

While small Neptune-like planets are among the most abundant exoplanets, our understanding of their atmospheric structure and dynamics remains sparse. In particular, many unknowns remain regarding the way moist convection works in these atmospheres, where condensable species are heavier than the non-condensable background gas. While it has been predicted that moist convection could cease above some threshold abundance of these condensable species, this prediction is based on simple linear analysis and relies on some strong assumptions regarding the saturation of the atmosphere. To investigate this issue, we developed a 3D cloud-resolving model for hydrogen-dominated atmospheres with large amounts of condensable species and applied it to a prototypical temperate Neptune-like planet – K2-18 b. Our model confirms the inhibition of moist convection above a critical abundance of condensable vapor and the onset of a stably stratified layer in the atmosphere of such planets, which leads to much hotter deep atmospheres and interiors. Our 3D simulations further provide quantitative estimates of the turbulent mixing in this stable layer, which is a key driver of the cycling of condensables in the atmosphere. This allowed us to build a very simple, yet realistic, 1D model that captures the most salient features of the structure of Neptune-like atmospheres. Our qualitative findings on the behavior of moist convection in hydrogen atmospheres go beyond temperate planets and should also apply to regions where iron and silicates condense in the deep interior of hydrogen-dominated planets. Finally, we used our model to investigate the likelihood of a liquid ocean beneath an H2-dominated atmosphere on K2-18 b. We find that the planet would need to have a very high albedo (A &gt; 0.5–0.6) to sustain a liquid ocean. However, due to the spectral type of the star, the amount of aerosol scattering that would be needed to provide such a high albedo is inconsistent with the latest observational data.

Analysis of potential Circular RNAs in regulating imatinib resistance of Gastrointestinal stromal tumor.

Recent studies have found that circular RNA is an abundant RNA species that belongs to part of the competing endogenous RNA network(ceRNA), which was proven to play an important role in the development, diagnosis and progress of diseases. However, the function of circRNAs in imatinib resistance in Gastrointestinal stromal tumor (GIST) are poorly understood so for. The present study aimed to screen and predict the potential circRNAs in imatinib resistance of GIST using microarray analysis. We determined the expression of circular RNAs in paired normal gastric tissues(N), primary GIST (gastrointestinal stromal tumor) tissues (YC) and imatinib mesylate secondary resistance GIST tissues(C) with microarray and predicted 8677 dysregulated circular RNAs. Compared with the YC group, we identified 15 circRNAs that were up-regulated and 8 circRNAs that were down-regulated in the C group. Gene ontology (GO)and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis indicated that these host linear transcripts that differentially express circular RNAs are involved in many key biological pathways, predicting the potential tumor-genesis and drug resistance mechanismrelated to HIF-1 pathway, later we draw the cirRNA-miRNA-mRNA network involved in the HIF-1 pathway and found several dysregulated circRNAs and the relationship between circRNA-miRNAs-mRNA, such as circRNA_06551, circRNA_14668, circRNA_04497, circRNA_08683, circRNA_09923(Green, down-regulation) and circRNA_23636, circRNA_15734(Red, up-regulation). Taken together, we identified a panel of dysregulated circRNAs that may be potential biomarkers even therapy relevant to the GIST, especially imatinib secondary resistance GIST.

Melanoma tumor microbiome as a predictor of anti-PD-1 and anti-CTLA-4 immunotherapy response.

e14666 Background: In 2023, it is estimated that 97,610 melanoma diagnoses were made in the United States, resulting in 7,990 deaths. For high-risk melanomas, immune checkpoint inhibitors are often administered as an adjuvant to surgery, though they yield variable response rates. The gut microbiome’s association to these treatments’ success has been demonstrated, largely through fecal transplant and probiotic trials. In this study, we seek to determine whether tissue-resident microbes in melanoma tumors could be used to predict immunotherapy response. Methods: Sequencing data of 289 melanoma tumor tissue samples was downloaded across three distinct studies. Intratumor microbial species abundances were derived from RNA or DNA sequencing data through direct alignment to microbial reference databases. Gene expression profiling was also performed. Microbial abundance values were used to construct models predicting patients’ responses to check-point blockade immunotherapies, which were then validated on an external dataset. Results: 12 and 14 microbial species were differentially abundant in anti-PD-1 responders and anti-CTLA-4 responders, respectively. We identified significant correlations of these species to genes of the PD-1 and CTLA-4 signaling pathways. Among others, greater abundance of Corynebacterium kroppenstedtii and Streptococcus gordonii correlated to decreased expression of PD1 and CTLA-4. With the abundances of these taxa and the expressions of 37 genes known to be implicated in immunotherapy response, we developed two classifiers to predict a patient’s response to anti-PD-1 and anti-CTLA-4 therapies. When tested externally, these models successfully predicted a majority of responders and non-responders with sensitivities of 80.0% and 60.0% and specificities of 95.2% and 95.8%, respectively. Conclusions: Our study revealed that checkpoint blockade response for melanomas could be predicted with microbe abundances. Our analysis demonstrates the potentially promising clinical utility of intratumor microbiota in cancer treatment. Given their location in the tumor microenvironment and their ability to influence immune processes, intratumor microbes could play a critical role in modulating the therapeutic effects of immune checkpoint blockades. We hope that our results could also be applied to other solid tissue cancers, where a significantly smaller fraction of patients respond to immunotherapy. [Table: see text]

Sediment dynamics and geomorphology in coastal areas affect long-term abundance of waders

Millions of migrating and wintering waders depend on coastal areas and estuaries for feeding and to replenish body reserves. These habitats are dynamic, with changing intertidal flats and sediments due to natural and climate-driven processes. The aims of this study were to examine whether physical conditions of intertidal flats such as geomorphology and sediment compositions could explain abundance of wader species, and furthermore whether changes in these conditions over time influenced changes in abundance of waders. In addition to physical structures such as datum (level), slope and sediment composition of intertidal flats, dynamic variables connected to tidal cycles such as distance of the waterline from the coast and duration of water cover were included. Penetration of the sea floor was measured as a proxy for sediment composition. The study was conducted in the Danish section of the Wadden Sea during 1981–1986 and 2008–2009 with additional data from 2020. The focus was on 12 widespread wader species. PCA analysis revealed that wader species were distributed in relation to tidal cycles such as duration of water cover and the position of waterline and to the physical structures, datum, slope and penetration, in decreasing order. With regard to the physical structures, pairwise comparisons of distribution of waders species showed that mean datum (level) was significantly different for 51 pairs of species out of 66 comparisons, mean penetration values differed for 34 pairs, and mean slope differed for 26 pairs of wader species. Long-term changes of physical structures of transects revealed that changes of densities of 10 wader species were significantly correlated with changes per year in one or more of the physical structures: seven wader species were significantly correlated with changes per year of mean datum (level) of transects (Lapwing was positively correlated while Avocet, Golden Plover, Grey Plover, Dunlin, Bar-tailed Godwit and Redshank were negatively correlated), five species with mean slope (Oystercatcher, Ringed Plover and Knut were positively correlated and Grey Plover and Redshank were negatively correlated), and three species with mean penetration values (sediment composition) of transects (Avocet and Bar-tailed Godwit were positively correlated and Lapwing was negatively correlated). The study shows that long-term changes of physical structures of intertidal flats affected abundance of wader species. The results are important for interpretation effects of erosion and accretion of coastal areas as consequences of natural and climate driven processes such as sea level rise and coastal squeeze.

Gadolinium-doped SrFeO3 as a highly active and stable electrode for symmetrical solid oxide fuel cells

Symmetrical solid oxide fuel cells (SSOFCs) with identical electrodes have gained interesting attention because of their simplified fabrication procedure and reduced processing costs. However, their development is limited by their electrocatalytic activity and stability of the electrode materials used. Here, we report a prototypical SrFeO3-δ-based perovskite oxide with formula GdxSr1-xFeO3-δ (GSF) as a highly effective SSOFC electrode material. It was found that A-site Gd substitution in SrFeO3-δ greatly improved its structural stability under reducing atmosphere. Furthermore, doping Gd was able to significantly enhance the electrochemical activity, achieving area-specific resistances of 0.18 Ω cm2 for the cathode and 0.003 Ω cm2 for the anode at 800 °C, respectively. The lower polarization resistance could be attributed to the abundant surface oxygen species through the Gd-doping in SrFeO3-δ. Benefiting from superior electrochemical activity and structural stability, the symmetrical cell with GSF-0.2 electrode showed reasonable stability and electrochemical performance. These results show that the developed GSF perovskite oxide may be a promising candidate as electrode material for symmetrical SOFCs.