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Spinel cobalt oxide displays excellent photocatalytic performance, especially in solar driven water oxidation. However, the process of water reduction to hydrogen is considered as the Achilles' heel of solar water splitting over Co3 O4 owing to its low conduction band. Enhancement of the water splitting efficiency using Co3 O4 requires deeper insights of the carrier dynamics during water splitting process. Herein, the carrier dynamic kinetics of colloidal Co3 O4 quantum dots-Pt hetero-junctions is studied, which mimics the hydrogen reduction process during water splitting. It is showed that the quantum confinement effect induced by the small QD size raised the conduction band edge position of Co3 O4 QDs, so that the ligand-to-metal charge transfer from 2p state of oxygen to 3d state of Co2+ occurs, which is necessary for overall water splitting and cannot be achieved in Co3 O4 bulk crystals. The findings in this work provide insights of the photocatalytic mechanism of Co3 O4 catalysts and benefit rational design of Co3 O4 -based photocatalytic systems.
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Oxygen vacancy-rich titania is a promising support for enhancing the hydrogen evolution reaction (HER). This work innovatively loaded Pt nanoparticles on oxygen vacancy-rich TiO2 (Pt/Vo-TiO2) in situ by using a photocatalytic device. The synthesis conditions are mild, do not require high temperatures and strong reducing agents, and can avoid the accumulation of platinum species. X-ray photoelectron spectroscopy (XPS) and X-ray absorption spectrometry (XAS) verified the synergistic effect of Pt species and oxygen vacancies on the progress of the reaction kinetics, where the Pt particles exposed by the in situ synthesis functioned as reaction sites in the electrocatalytic hydrogen evolution. Based on this, Pt/Vo-TiO2 exhibits excellent electrocatalytic performance with an overpotential of only 56 mV at a current density of 10 mA cm-2 and a Tafel slope of only 73.5 mV dec-1. This work provides a new strategy for designing highly efficient HER catalysts.
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Solar-driven water splitting to produce clean and renewable hydrogen offers a green strategy to address the energy crisis and environmental pollution. Heterostructure catalysts are receiving increasing attention for photocatalytic hydrogen generation. ZnO/ZnS/CdS and ZnO/CdS heterostructures have been successfully designed and prepared according to two different strategies. By introducing a heterointerface layer of ZnS between ZnO and CdS, a Z scheme charge-transfer channel was promoted and achieved superior photocatalytic performance. A highest hydrogen generation rate of 156.7â µmol g-1 h-1 was achieved by precise control of the thickness of the heterointerface layer and of the CdS shell. These findings demonstrated that heterostructures are promising catalysts for solar-driven water splitting, and that heterointerface engineering is an effective way to improve the photocatalytic properties of heterostructures.
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Hidrogênio , ÁguaRESUMO
The NiO-based electrocatalytic oxygen evolution reaction (OER) of water splitting is recognized as a promising approach to produce clean H2 fuel. However, the OER performance is still low, and especially, the overpotential is larger than 200 mV at the current density of 10 mA cm-2 . Herein, an Ir@IrNiO sample is prepared with single-atom (SA) Ir4+ doping and surface metallic Ir nanoparticles loaded onto the NiO. Owing to the bonding of the loaded Ir with surface-exposed Ni2+ , the nearby Ni atoms exist in the +3 valence state, that is, the surface-loaded Ir particles behave like a stabilizer for the Ni3+ sites. Under the synergistic effect of SA Ir4+ and high-valance-state Ni3+ , the Ir@IrNiO nanostructure effectively reduces the overpotential to 195 mV at a current density of 10 mA cm-2 . Moreover, it gives an Ir-content-normalized current density of 0.0457 A mgIr -1 , 72.1 times higher than that of the best commercialized IrO2 (6.33 × 10-4 A mgIr -1 ), under the condition of 1.5 V versus reversible hydrogen electrode. Operando Raman and X-ray absorption fine-structure (XAFS) measurements reveal that there are more surface-active species of Ni3+ , which adsorb and activate water molecules to form Ni3+ -*OH at low voltage, the intermediate of Ni4+ -â¢O is then formed at a relatively high bias voltage, and then the â¢O is transferred to the SA Ir4+ sites to generate Ir4+ -O-O with OH at increased voltage. This work can help design more SA-based highly active OER materials.
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This study aimed to research the effects of forest (Pinus elliottii, slash pine) and shrub (Vitex trifolia) plantation on the soil microbial community in sandification land by using the Illumina Miseq sequencing of 16S rRNA and ITS rRNA genes and combined with the soil properties analysis to explore the driving factors. Finally, the results showed that the dominant bacterial phyla were Chloroflexi, Actinobacteria, Proteobacteria, and Acidobacteria; the shrub and forest plantation significantly increasing the proportion of Acidobacteria, while decreasing the proportion of Proteobacteria. For the fungal community, forest plantation was significantly changing the community structure at the phylum level that shifted from Ascomycota to Basidiomycota, and the ectomycorrhizal fungi take the most abundant with genus Rhizopogon predominant. The soil bacterial Chao1 and Shannon indices were significantly increased after revegetation, while the soil fungal Shannon diversity in the forest land that significantly correlated with soil total organic carbon and C/N was lower than that in the sandy and shrub land (p < 0.05). Besides, the bacterial and fungal communities were significantly affected by soil water content among all analyzed soil properties. Our results suggest that the revegetation significantly increasing the soil bacterial diversity that correlated with soil water content, total organic carbon, and available phosphorus, but there was no significant change in community structure. In contrast, slash pine plantation changes the fungal community structure and diversity dramatically. This change and possible succession of fungal community with stand age increasing may lead to the fragility of the plantation, which deserves continuous attention.
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Micobioma , Solo , China , Monitoramento Ambiental , RNA Ribossômico 16S , Microbiologia do SoloRESUMO
Multi-field coupling, especially photo-assisted electrocatalysis, has recently been studied to further improve the oxygen evolution reaction (OER). In this study, an n-type cubic In2 O3 semiconductor is employed for the first time to load IrOx species (Ir-In2 O3 mass ratio: 17.6 %). Consequently, the IrOx @In2 O3 heterojunction, which exhibits outstanding OER performance promoted by weak-light irradiation, is formed. Notably, IrOx (approximately 1.7â nm in size) and In2 O3 are observed to crystallize independently during heterogeneous nucleation with no Ir atoms doped in the In2 O3 lattice. This avoids Ir loss and ensures the full exposure of all Ir-based sites. The IrOx @In2 O3 heterojunction exhibits enhanced electrocatalytic water oxidation with overpotential values of 190 and 231â mV at current densities of 10 and 50â mA cm-2 , surpassing all IrOx -based catalyst results reported to date. Nano-sized IrOx on the surface, irradiated by the weak-light beam of LED-365 (1.8â mW cm-2 ), can be fully activated as an OER site. Moreover, the overpotential is further reduced to 176 and 210â mV to deliver the corresponding current. This work is anticipated to aid in the design of more efficient multi-field coupling OER systems.
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Effective transfer and utilization of the photogenerated electrons are a key factor for achieving highly efficient H2 generation by photocatalytic water splitting. Apart from the activity of the co-catalyst, the interface between the co-catalyst and semiconductor is of particular importance. Guided by DFT calculations, single-atom (SA) Pt doped carbon nitride (CN) is successfully synthesized for use as the co-catalyst to the semiconducting CuS. The catalyst system (Pt1-CN@CuS) exhibits an enhanced photocatalytic performance for water splitting with a H2 production rate of 25.4â µmol h-1 and an apparent quantum yield (AQY) of 50.3 % under the illumination of LED-530. Solar-to-hydrogen (STH) conversion efficiency is calculated to be 0.5 % under AMâ 1.5 illumination. This is the very first investigation of SA as the co-catalyst, which decreases the overpotential of CN during the water splitting and lowers interfacial resistance of the catalyst/co-catalyst and co-catalyst/electrolyte.
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BACKGROUND: Cases of duodenal variceal hemorrhage after cirrhosis are rare, but patients have a higher mortality rate. There is currently no clinical guideline to address how such patients should choose preferred treatment. METHODS: We retrospectively evaluated the clinical information of a 65-year-old male admitted to the Gastroenterology Department with gastrointestinal bleeding. RESULTS: The patient was eventually diagnosed with duodenal variceal bleeding after cirrhosis. We performed TIPS on the patients after the vital signs were stable. No varicose veins were seen by endoscopy during the 2-year follow-up. CONCLUSIONS: TIPS treatment is a good choice for patients with severe duodenal varices after cirrhosis.
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Varizes Esofágicas e Gástricas , Varizes , Idoso , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/terapia , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/diagnóstico , Masculino , Estudos Retrospectivos , Varizes/complicações , Varizes/diagnóstico , Varizes/terapiaRESUMO
In artificial photocatalytic hydrogen evolution, effective incident photon absorption and a high-charge recombination rate are crucial factors influencing the overall efficiency. Herein, a traditional solid-state synthesis is used to obtain, for the first time, novel samples of few-layered g-C3 N4 with vertically aligned MoS2 loading (MoS2 /C3 N4 ). Thiourea and layered MoO3 are chosen as precursors, as they react under nitrogen atmosphere to in situ produce the products. According to the quasi-Fourier transform infrared reflectance and X-ray diffraction measurements, the detailed reaction process is determined to proceed through the confirmed formation pathway. The two precursor units MoS2 and C3 N4 are linked by MoN bonds, which act as electronic receivers/conductors and hydrogen-generation sites. Density functional theory is also carried out, which determines that the interface sites act as electron-accumulation regions. According to the photoelectrochemical results, MoS2 /C3 N4 can achieve a current of 0.05 mA cm-2 , which is almost ten times higher than that of bare g-C3 N4 or the MoS2 /C3 N4 -R reference samples. The findings in the present work pave the way to not only synthesize a series of designated samples but also thoroughly understand the solid-state reaction.
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Two stable 3D polyoxometalate-based metal-organic frameworks (PMOFs), [CuI12(trz)8(H2O)2][α-SiW12O40]·2H2O (1) and [CuI12(trz)8Cl][α-PW12O40] (2) (Htrz = 1- H-1,2,4-triazole) based on Keggin-type POMs were successfully obtained and fully characterized. The basic building units of the two PMOFs are [CuI12(trz)8], but polyoxoanion (POA) template effect leads to different structures and properties: 1 represents an interesting example that [α-SiW12O40]4- locate in the nine-membered Cu-trz rings through Cu···O weak interactions to form a 3D framework, whereas 2 shows a 3D structure constructed from 2D bilayer cationic network [CuI12(trz)8Cl]3+ and [α-PW12O40]3- lying in the adjacent layers via Cu···O weak interactions. PMOF 1 as unusual visible-light photocatalyst exhibit significantly enhanced photocatalytic activity under visible-light and excellent stability during the photocatalysis process for recovering and recycling, as well as photocatalytic hydrogen evolution activity.
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AIM: We aimed to investigate sleep quality, mild hepatic encephalopathy, anxiety, and depression in patients with hepatitis B cirrhosis by using a variety of scales and questionnaires. METHOD: A cohort of 341 patients with hepatitis B liver cirrhosis were categorized by Child-Pugh grading (A, B, and C) in this cross-sectional study. Pittsburgh Sleep Quality Index (PSQI), Number Connection Test-A (NCT-A), and Hospital Anxiety and Depression (HAD) evaluated the questionnaires and statistically analyzed the intrinsic correlation. The control group included 50 healthy individuals. Of 341 patients, 213 had a PSQI index >5 points. RESULTS: The PSQI, NCT-A, anxiety scale (HAD [a]), and depression scale (HAD [d]) of the patients were significantly different. The NCT-A-positive patients revealed 214 cases of possible minimal hepatic encephalopathy (MHE) during a preliminary screening of patients. The PSQI score of NCT-A-positive patients was significantly elevated compared to NCT-A-negative patients (P < 0.001). HAD (a) and HAD (d) were significantly different between the NCT-A-positive and NCT-A-negative groups (P = 0.002 and P = 0.006, respectively). Univariate Pearson's correlation analysis found that NCT-A and HAD (a) were positively correlated with PSQI (P < 0.001 and P = 0.045, respectively); however, Child-Pugh score and HAD (d) were not correlated with PSQI (P = 0.061 and P = 0.059, respectively). CONCLUSION: These results indicated that patients with hepatitis B liver cirrhosis have a disturbed sleep, which might be an MHE symptom, further causing considerable anxiety. Thus, the evaluation of sleep quality and psychological state of patients with hepatitis B liver cirrhosis necessitates further investigation to guide positive intervention.
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A P doped MoO3-x nanocomposite material with rich oxygen vacancies is successfully fabricated by a two-step intercalation method, which presents superior activity for the hydrogen evolution reaction with low overpotential and fast electron transfer. In 0.5 m H2 SO4 , it displays an overpotential of 166 mV for driving the current density of 10 mA cm-2 . Moreover, it also shows a good catalytic stability in the electrolytes with different pH, 0.5 m H2 SO4 (strong acid), 0.5 m Na2 SO4 (neutral solution), and 0.1 m NaOH (strong base). The superior catalytic activity and stability are due to to the synergistic effect between the P element doping and the oxygen vacancies.
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This study employed Mendelian randomization (MR) analysis to systematically investigate the potential connections between gut microbiota and the risk of glioblastoma (GBM). We identified 12 microbial groups closely associated with the incidence risk of GBM. Subsequently, MR analysis was conducted on 1,091 blood metabolites and 309 metabolite ratios, revealing 19 metabolites that exert an impact on the occurrence of GBM. Hypothesizing that gut microbiota may influence the risk of glioblastoma multiforme by modulating these metabolites, we performed MR analyses, considering each microbial group as exposure and each metabolite as an outcome. Through these analyses, we constructed a regulatory network encompassing gut microbiota, metabolites, and GBM, providing a novel perspective for a deeper understanding of the role of the gut-brain axis in the pathogenesis of GBM. This research offers crucial insights into how gut microbiota may affect the risk of GBM by regulating specific metabolites. The identified regulatory network of the gut-brain axis may play a significant role in the formation and development of GBM, providing valuable information for future research and therapeutic interventions.
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Production of hydrogen (H2) fuel by using hydrogen evolution reaction (HER) through electrocatalysis of water splitting is inexpensive, has optimal performance, and has remarkable stability. The other key factor for innovation of good electrocatalysts with excellent stability and high efficiency is significant and still challenging from past decades for practical applications of HER. Hydrogen generation arises on the HER electrode due to the release of bubbles, proton diffusion, and the transfer of electrons. These considerations should be mindful of the construction and development of the electrode. This review offers a synopsis of recent advancements in various electrodes used for electrocatalysts as a base, such as nickel foam, titanium foil, copper foam, carbon foam, and others, also discusses their HER catalytic activity, with a priority on the release of bubbles, diffusion of ions, the structure of the electrode, and the formulation and preparation process. In conclusion, we provide an overview of ideas to further improve and address the significant issues in the manufacture of HER electrodes.
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Numerous studies have explored the various functions of Slc40a1 in cancer development. However, the role of Slc40a1 in primary glioblastoma requires further investigation. Initially, we observed that GBM patients with high Slc40a1 expression had a more favorable prognosis than those with low Slc40a1 expression, as evidenced by an analysis of the TIMER database. Subsequent analysis using the cancer genome atlas (TCGA) database enabled us to identify potential underlying mechanisms involved. Further analyses, including GO, KEGG, GSEA, immune infiltration, and correlation analyses, revealed that Slc40a1 primarily affected cytokine interactions, particularly with Ccl14 and Il18, resulting in changes in the immune microenvironment and ultimately leading to a better prognosis in GBM patients. We validated our findings by examining a tissue microarray with 180 samples and confirmed that GBM patients with high SLC40A1 protein expression exhibited more favorable prognostic outcomes than those with low SLC40A1 protein expression. Immunofluorescence analysis also revealed a significant correlation between SLC40A1 protein expression and the protein expression of IL18 and CCL14. These findings suggest that Slc40a1 may play a role in GBM pathogenesis by modulating the tumor immune microenvironment through the regulation of Il18 and Ccl14. Hence, targeting Slc40a1 might offer potential benefits for immunotherapeutic interventions and prognostic assessments in GBM patients.
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Neoplasias Encefálicas , Proteínas de Transporte de Cátions , Glioblastoma , Microambiente Tumoral , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/genética , Proteínas de Transporte de Cátions/genética , Citocinas , Regulação Neoplásica da Expressão Gênica , Glioblastoma/imunologia , Glioblastoma/genética , Interleucina-18/genética , Prognóstico , Microambiente Tumoral/imunologiaRESUMO
The sole effect of surface/bulk defects of TiO2 samples on their photocatalytic activity was investigated. Nano-sized anatase and rutile TiO2 were prepared by hydrothermal method and their surface/bulk defects were adjusted simply by calcination at different temperatures, i.e. 400-700 °C. High temperature calcinations induced the growth of crystalline sizes and a decrease in the surface areas, while the crystalline phase and the exposed facets were kept unchanged during calcination, as indicated by the characterization results from XRD, Raman, nitrogen adsorption-desorption, TEM and UV-Vis spectra. The existence of surface/bulk defects in calcined TiO2 samples was confirmed by photoluminescence and XPS spectra, and the surface/bulk defect ratio was quantitatively analyzed according to positron annihilation results. The photocatalytic activity of calcined TiO2 samples was evaluated in the photocatalytic reforming of methanol and the photocatalytic oxidation of α-phenethyl alcohol. Based on the characterization and catalytic results, a direct correlation between the surface specific photocatalytic activity and the surface/bulk defect density ratio could be drawn for both anatase TiO2 and rutile TiO2. The surface defects of TiO2, i.e. oxygen vacancy clusters, could promote the separation of electron-hole pairs under irradiation, and therefore, enhance the activity during photocatalytic reaction.
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Catalytic methane decomposition (CMD) has emerged as an appealing technology for large-scale production of H2 and carbon nanostructures from natural gas. As the CMD process is mildly endothermic, the application of concentrated renewable energy sources such as solar energy under a low-temperature regime could potentially represent a promising approach towards CMD process operation. Herein, Ni/Al2O3-La2O3 yolk-shell catalysts are fabricated using a straightforward single-step hydrothermal approach and tested for their performance in photothermal CMD. We show that the morphology of the resulting materials, dispersion and reducibility of Ni nanoparticles, and nature of metal-support interactions can be tuned by addition of varying amounts of La. Notably, the addition of an optimal amount of La (Ni/Al-20La) improved the H2 yield and catalyst stability relative to the base Ni/Al2O3 material, while also favoring base growth of carbon nanofibers. Additionally, we show for the first time a photothermal effect in CMD, whereby the introduction of 3 suns light irradiation at a constant bulk temperature of 500 °C reversibly increased the H2 yield of catalyst by about 1.2 times relative to the rate in the dark, accompanied by a decrease in apparent activation energy from 41.6 kJ mol-1 to 32.5 kJ mol-1. The light irradiation further suppressed undesirable CO co-production at low temperatures. Our work reveals photothermal catalysis as a promising route for CMD while providing an insightful understanding of the roles of modifier in enriching methane activation sites on Al2O3-based catalysts.
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Background: Freshwater fungi refer to the fungi that depend on the freshwater habitats for the whole life cycle or part of their life cycle. In this context, a new aquatic hyphomycete was isolated from decaying wood in a freshwater habitat in Jiangxi Province, China. New information: Dictyochaetajiangxiensis sp. nov., a new aquatic hyphomycete, is characterised by its unbranched, septate, base-fertile conidiophores with multisepta and single phialide at the apex, brown, sterile seta, monophialidic, subcylindrical conidiogenous cells narrowing below the funnel-shaped collarette, hyaline, unicellular, thin-walled, smooth, guttulate, falcate to subclavate conidia narrowly rounded at both ends with hair-like appendages. Phylogenetically, the new species Dictyochaetajiangxiensis clustered together with Dictyochaetabrevis MFLU 19-0216 in a well-supported clade, but formed a separate branch. In order to better define the taxonomic status of the new species, a phylogenetic tree of most closely-related taxa in Chaetosphaeriaceae was established, based on multi-locus sequences (ITS and LSU). The novel species is described and illustrated. Newly-generated molecular data of Dictyochaetajiangxiensis is also provided.
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Aim: The present study aimed to evaluate the durability of immune response after basic and booster immunization with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines in patients with chronic liver disease (CLD). Methods: Patients with CLD and complete basic or booster immunization with SARS-CoV-2 vaccines were included in this study. Based on the vaccination situation, they were divided into the basic immunity group (Basic) and the booster immunity group (Booster), which were then subdivided into four groups according to the time interval from completion of basic immunization or booster immunization to serological specimen collection. The positive rates and antibody titers of novel coronavirus neutralizing antibody (nCoV NTAb) and novel coronavirus spike receptor-binding domain antibody (nCoV S-RBD) were analyzed. Results: A total of 313 patients with CLD were enrolled in this study, including 201 in Basic and 112 in Booster. The positive rates of nCoV NTAb and nCoV S-RBD within 30 days of completing basic immunization were 80.4% and 84.8%, respectively, but decreased rapidly with the extension of vaccination time, and only 29% and 48.4% of patients with CLD remained positive for nCoV NTAb and nCoV S-RBD, respectively, after 120 days of completing basic immunization. Within 30 days of booster immunization, the positive rates of nCoV NTAb and nCoV S-RBD in patients with CLD rapidly increased from 29.0% and 48.4% at the end of basic immunization to 95.2% and 90.5%, and maintained a high level (defined as the positive rate >50%) until 120 days when the positive rates of nCoV NTAb and nCoV S-RBD were still high at 79.5% and 87.2%, respectively. After basic immunization, the time for nCoV NTAb and nCoV S-RBD to turn negative was 120 and 169 days, respectively, and the negative time of nCoV NTAb and nCoV S-RBD was significantly prolonged to 266 days and 329 days, respectively. Conclusion: It is safe and effective for patients with CLD to complete basic and booster immunization with SARS-CoV-2 vaccines. After booster immunization, the immune response of patients with CLD was further improved and the durability of the SARS-CoV-2 antibody was significantly prolonged.
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COVID-19 , Hepatopatias , Humanos , Vacinas contra COVID-19 , SARS-CoV-2 , COVID-19/prevenção & controle , Vacinação , Anticorpos Neutralizantes , Anticorpos Antivirais , ImunidadeRESUMO
Iugisporipsathyra, a new psathyrelloid genus from tropical red soil of China, is established with I.reticulopilea as the type species. The new genus is characterised by basidiomata psathyrelloid, pileus rugose to appearing reticulate ridged, covered by persistent, but inconspicuous villus, pleurocystidia absent and ridge-ornamented spores with an obvious suprahilar plage. The genus is unique amongst Psathyrellaceae in producing ridge-ornamented spores with an obvious suprahilar plage and forms a distinct lineage within Psathyrellaceae, based on the Maximum Likelihood and Bayesian Inference analyses of a combined three-gene sequence dataset (ITS, LSU and ß-tub). Full descriptions and photographs of the new genus and species are presented.