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The existence of scalar fields can be probed by observations of stochastic gravitational waves. Scalar fields mediate attractive forces, usually stronger than gravity, on the length scales shorter than their Compton wavelengths, which can be non-negligible in the early Universe, when the horizon size is small. These attractive forces exhibit an instability similar to the gravitational instability, only stronger. They can, therefore, lead to the growth of structures in some species. We identify a gravitational waves signature of such processes and show that it can be detected by future gravitational waves experiments.
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Growing consumer interest in healthy foods has led to an increased demand for bioactive compounds derived from eco-technologies. This review highlighted two emerging technologies, pressurized liquid extraction (PLE) and supercritical fluid extraction (SFE), which are based on clean processes aimed at recovering bioactive compounds from different food sources. We studied how the different processing conditions provide many advantages and a great opportunity to obtain compounds with antioxidant, antibacterial, antiviral, or antifungal activity from plant matrices and industrial biowaste, especially antioxidant compounds (anthocyanins and polyphenols) due to their important role in health promotion. Our research was conducted through a systematic search in different scientific databases related to the PLE and SFE topics. The review analyzed the optimal extraction conditions using these technologies, which lead to the efficient extraction of bioactive compounds, the use of different equipment, and recent combinations of SFE and PLE with other emerging technologies. This has given rise to the development of new technological innovations, new commercial applications, and the detailed recovery of various bioactive compounds extracted from different plant and marine life food matrices. These two environmentally friendly methodologies are fully valid and have great future application prospects in biowaste valorization. They represent a feasible technological tool that can promote the implementation of a circular economy model for the food industry. The underlying mechanisms of these techniques were discussed in detail and supported by current literature.
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Cromatografia com Fluido Supercrítico , Eliminação de Resíduos , Antioxidantes/farmacologia , Alimentos , Antocianinas , Tecnologia , Cromatografia com Fluido Supercrítico/métodosRESUMO
This study aimed to assess the trends of health-related cardiorespiratory fitness (CRF) during two school years with a 3-month summer break in children and adolescents. A 2-year longitudinal study, including 440 6th to 8th graders (218 boys), mean age 12.3 years, was conducted. The Progressive Aerobic Cardiovascular Endurance Run (PACER) was used to assess CRF. Physical activity was measured using accelerometers. Repeated measures linear models were used to analyses differences and trends in VO2peak and health-related CRF. Overall differences between time-point VO2peak were significant for both boys (p<0.001) and girls (p=0.003). Pairwise comparisons showed that VO2peak improved from the beginning to the end of the same school year for boys (school-year 1: 1.53 ml/kg/min, 95%CI=0.98, 2.09; school-year 2: 1.81 ml/kg/min, 95%CI=1.28, 2.34) and girls (school-year 1: 0.85 ml/kg/min, 95%CI=0.43, 1.27; school-year 2: 1.05 ml/kg/min, 95%CI=0.73, 1.36), while, differences in CRF during summer break were not significant. However, significance was only maintained for girls when performing monthly adjusted analysis. Improvements in CRF were observed during school year and remained unchanged during summer break. These findings provide relevant information for the health education community, suggesting the need for additional efforts to counteract the summer break effects on CRF, especially for girls.
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Aptidão Cardiorrespiratória , Adolescente , Criança , Exercício Físico , Feminino , Humanos , Estudos Longitudinais , Masculino , Aptidão Física , Instituições Acadêmicas , Estações do AnoRESUMO
We describe a new scenario for the formation of primordial black holes (PBHs). In the early Universe, the long-range forces mediated by the scalar fields can lead to formation of halos of heavy particles even during the radiation-dominated era. The same interactions result in the emission of scalar radiation from the motion and close encounters of particles in such halos. Radiative cooling due the scalar radiation allows the halos to collapse to black holes. We illustrate this scenario on a simple model with fermions interacting via the Yukawa forces. The abundance and the mass function of PBHs are suitable to account for all dark matter, or for some gravitational wave events detected by LIGO. The model relates the mass of the dark-sector particles to the masses and abundance of dark matter PBHs in a way that can explain why the dark matter and the ordinary matter have similar mass densities. The model also predicts a small contribution to the number of effective light degrees of freedom, which can help reconcile different measurements of the Hubble constant.
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The COVID-19 pandemic has forced the health public authorities to impose a lockdown as an epidemiological containment strategy. This study aimed to provide information regarding the impact of the mandatory confinement on the physical activity, eating disorders risk, sleep quality and well-being on a Spanish sample. An online survey that included the Minnesota Leisure Time Physical Activity Questionnaire, the Eating Attitude Test-26, and Pittsburgh Sleep Quality Index was administered two days after the state of alarm was stablished in Spain and five days after such measures began to be eased. Out of the 693 people who answered the first questionnaire, 161 completed the second one. These participants spent a total of 48 days locked at home, a period during which a significant worsening in all the variables assessed except for the risk of developing eating disorders, was observed: weight (kg), 67.3 ± 14.8 vs 67.7 ± 15.1, p = 0.012; physical activity (MET minutes per week), 8515.7 ± 10260.0 vs 5053.5 ± 5502.0, p < 0.001; sleep problems (total score), 6.2 ± 3.5 vs 7.2 ± 3.9, p < 0.001; self-perceived well-being (score), 4 (3-4) vs 3 (3-4), p < 0.001. The confinement had a significant differential effect on physically active participants, who experienced a significant decline (p < 0.05) on their physical activity levels, quality of sleep and well-being; whereas physically inactive participants did not experience significant changes. Findings from this longitudinal study indicate that a lockdown period due to COVID-19 had a negative impact on the physical activity levels, sleep quality and well-being in a group of physically active Spanish adults. Public health authorities should be aware that people who usually lead an active lifestyle, might be particularly susceptible to such disruptions.
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COVID-19 , Exercício Físico , Comportamento Alimentar , Pandemias , Comportamento Sedentário , Sono , Isolamento Social , Adulto , Idoso , Controle de Doenças Transmissíveis , Dieta , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , SARS-CoV-2 , Espanha/epidemiologia , Inquéritos e Questionários , Adulto JovemRESUMO
Here we report on the design and characterization of calcium-alginate microgels (MGs) containing positively charged iron oxide nanoparticles (IONPs) and negatively charged oil-in-water (O/W) nanocarriers (NCs). To provide ionic compatibility of IONPs with the negatively charged NCs and alginate in MGs, they were coated with the anionic polysaccharides alginate, carrageenan or sulfobutyl-ß-cyclodextrin. The mixing of both nanostructures (coated-IONPs and O/W NCs) with alginate solutions provide homogeneous dispersions able to form spherical hydrogels with different sizes (250-1400 micrometers) and encapsulating the nanostructures with high efficiency. MGs loaded with both nanostructures were reactive to continuous (attractive interaction) and alternating magnetic field (heat release similar to non-encapsulated IONPs). The encapsulation of both nanostructures in MGs was maintained even after 7 days of storage at 40 °C. We postulate that the above results will be of interest for the design of hydrogel formulations with therapeutic applications.
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Microgéis , Alginatos , Nanopartículas Magnéticas de Óxido de Ferro , ÁguaRESUMO
Avocado oil has generated growing interest among consumers due to its nutritional and technological characteristics, which is evidenced by an increase in the number of scientific articles that have been published on it. The purpose of the present research was to discuss the extraction methods, chemical composition, and various applications of avocado oil in the food and medicine industries. Our research was carried out through a systematic search in scientific databases. Even though there are no international regulations concerning the quality of avocado oil, some authors refer to the parameters used for olive oil, as stated by the Codex Alimentarius or the International Olive Oil Council. They indicate that the quality of avocado oil will depend on the quality and maturity of the fruit and the extraction technique in relation to temperature, solvents, and conservation. While the avocado fruit has been widely studied, there is a lack of knowledge about avocado oil and the potential health effects of consuming it. On the basis of the available data, avocado oil has established itself as an oil that has a very good nutritional value at low and high temperatures, with multiple technological applications that can be exploited for the benefit of its producers.
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Persea/química , Óleos de Plantas/farmacologia , Antioxidantes/farmacologia , Biotecnologia , Contaminação de Alimentos , Humanos , Óleos de Plantas/isolamento & purificaçãoRESUMO
Protein-functionalized cellulose fibrils, having various amounts of covalently bonded proteins at their surface, were successfully extracted from the tunic of Pyura chilensis tunicates using successive alkaline extractions. Pure cellulose fibrils were also obtained by further bleaching and were used as reference material. Extraction yields of protein-functionalized cellulose fibrils were within the range of 62-76% by weight based on the dry initial tunic powder. Fourier-transform infrared and Raman spectroscopy confirmed the preservation of residual protein at the surface of cellulose fibrils, which was then quantified by X-ray photoelectron spectroscopy. The protein-functionalized cellulose fibrils were found to have relatively high crystallinity and their cellulose I crystalline structure was preserved upon applying alkaline treatments. The extracted cellulosic materials were found to be constituted of fibrils having a ribbon-like morphology with widths ranging from â¼30 nm up to â¼400 nm. These protein-functionalized cellulose fibrils were found to have outstanding thermal stability with one of them having onset and peak degradation temperatures of â¼350 and 374 °C, respectively. These values were found to be 24 and 41 °C higher than for bleached cellulose.
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Celulose/análogos & derivados , Nanofibras/química , Proteínas/química , Animais , Temperatura Alta , Hidrólise , Urocordados/químicaRESUMO
An experimental protocol was studied to improve the adhesion of a polymeric poly(methyl methacrylate) coating that was modified with silver nanoparticles to an aluminum alloy, AA2024. The nanoparticles were incorporated into the polymeric matrix to add the property of inhibiting biofilm formation to the anticorrosive characteristics of the film, thus also making the coating antibiocorrosive. The protocol consists of functionalizing the surface through a pseudotransesterification treatment using a methyl methacrylate monomer that bonds covalently to the surface and leaves a terminal double bond that promotes and directs the polymerization reaction that takes place in the process that follows immediately after. This results in more compact and thicker poly(methyl methacrylate) (PMMA) coatings than those obtained without pseudotransesterification. The poly(methyl methacrylate) matrix modified with nanoparticles was obtained by incorporating both the nanoparticles and the methyl methacrylate in the reactor. The in situ polymerization involved combining the pretreated AA2024 specimens combined with the methyl methacrylate monomer and AgNps. The antibiofilm capacity of the coating was evaluated against P. aeruginosa, with an excellent response. Not only did the presence of bacteria decrease, but the formation of the exopolymer subunits was 99.99% lower than on the uncoated aluminum alloy or the alloy coated with unmodified poly(methyl methacrylate). As well and significantly, the potentiodynamic polarization measurements indicate that the PMMA-Ag coating has a good anticorrosive property in a 0.1-M NaCl medium.
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Ligas , Alumínio , Anti-Infecciosos , Materiais Revestidos Biocompatíveis , Nanopartículas Metálicas , Polimetil Metacrilato , Prata , Ligas/química , Alumínio/química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Biofilmes/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/química , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Testes de Sensibilidade Microbiana , Espectroscopia Fotoeletrônica , Polimetil Metacrilato/química , Pseudomonas aeruginosa/efeitos dos fármacos , Propriedades de SuperfícieRESUMO
The electronic structure of self-assembled monolayers (SAMs) formed by thiols of different lengths and dithiol molecules bound to Au(111) has been characterized. Inverse photoemission spectroscopy (IPES) and density functional theory have been used to describe the molecule/Au substrate system. All molecular layers display a clear signal in the IPES data at the edge of the lowest unoccupied system orbital (LUSO), roughly 3 eV above the Fermi level. There is also evidence, in both the experimental data and the calculation, of a finite density of states just below the LUSO edge, which has been recognized as localized at the Au-substrate interface. Regardless of the molecular lengths and in addition to this induced density of interface states, an apparent antibonding Au-S state has been identified in the IPES data for both molecular systems. The main difference between the electronic structures of thiol and dithiol SAMs is a shift in the energy of the antibonding state.
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(1) Background: Adolescents who are under the care of child and youth institutions are vulnerable due to factors that can include disruption to family structure or education and adverse experiences. They often experience poor or unstable support systems, leaving them at risk of delinquency. In this context, sports engagement may provide a stable structure and have positive effects in this population. Therefore, the purpose of this study was to explore the perceptions, knowledge, beliefs, and behaviors regarding social and emotional skills among at-risk adolescents, with a specific focus on their engagement in sports. (2) Methods: Ninety-six adolescents aged 12 to 17 years (66 female, 30 male), residing in child and youth care institutions across Italy, Portugal, the UK, and Turkey, participated in this study. The participants were divided into 14 focus groups, each with six to eight participants of similar ages. (3) Results: Thematic analysis revealed four main themes: Emotional causes of behavioral problems; Emotional skills to regain control; Social support makes sports worthwhile; Sport as a socio-emotional resource. (4) Conclusions: The study findings highlight that although sports create many challenging emotional situations for these adolescents, they also provides resources that may help them cope with their emotions within and beyond sports.
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The genus Tarzetta is distributed mainly in temperate forests and establishes ectomycorrhizal associations with angiosperms and gymnosperms. Studies on this genus are scarce in México. A visual, morphological, and molecular (ITS-LSU) description of T. americupularis, T. cupressicola, T. davidii, T. durangensis, T. mesophila, T. mexicana, T. miquihuanensis, T. poblana, T. pseudobronca, T. texcocana, and T. victoriana was carried out in this work, associated with Abies, Quercus, and Pinus. The results of SEM showed an ornamented ascospores formation by Mexican Taxa; furthermore, the results showed that T. catinus and T. cupularis are only distributed in Europe and are not associated with any American host.
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Climate change has evidenced the need to reduce carbon dioxide emissions into the atmosphere, and so for transport applications, lighter weight alloys have been studied, such as magnesium alloys. However, they are susceptible to corrosion; therefore, surface treatments have been extensively studied. In this work, the influence of argon plasma pretreatment on the surface properties of an AZ31 magnesium alloy focus on the enhancement of the reactivity of the surface, which was examined by surface analysis techniques, electrochemical techniques, and gravimetric measurements. The samples were polished and exposed to argon plasma for two minutes in order to activate the surface. Contact angle measurements revealed higher surface energy after applying the pretreatment, and atomic force microscopy showed a roughness increase, while X-Ray photoelectron spectroscopy showed a chemical change on the surface, where after pretreatment the oxygen species increased. Electrochemical measurements showed that surface pretreatment does not affect the corrosion mechanism of the alloy, while electrochemical impedance spectroscopy reveals an increase in the original thickness of the surface film. This increase is likely associated with the high reactivity that the plasma pretreatment confers to the surface of the AZ31 alloy, affecting the extent of oxide formation and, consequently, the increase in its protection capacity. The weight loss measurements support the effect of the plasma pretreatment on the oxide thickness since the corrosion rate of the pretreated AZ31 specimens was lower than that of those that did not receive the surface pretreatment.
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NO2 is one of the main greenhouse gases, which is mainly generated by the combustion of fossil fuels. In addition to its contribution to global warming, this gas is also directly dangerous to humans. The present work reports the structural and gas sensing properties of the CaCu3Ti4O12 compound prepared by the sol-gel technique. Rietveld refinement confirmed the formation of the pseudo-cubic CaCu3Ti4O12 compound, with less than 4 wt% of the secondary phases. The microstructural and elemental composition analysis were carried out using scanning electron microscopy and X-ray energy dispersive spectroscopy, respectively, while the elemental oxidation states of the samples were determined by X-ray photoelectron spectroscopy. The gas sensing response of the samples was performed for different concentrations of NO2, H2, CO, C2H2 and C2H4 at temperatures between 100 and 300 °C. The materials exhibited selectivity for NO2, showing a greater sensor signal at 250 °C, which was correlated with the highest concentration of nitrite and nitrate species on the CCTO surface using DRIFT spectroscopy.
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Objective This study aimed to analyze the actigraphy-based sleep parameters in wheelchair basketball (WB) athletes during the 3 weeks leading up to the playoffs, the week of playoffs, and the week after playoffs. Secondarily, the relationship between training load, sleep, and recovery was evaluated. Methods During 5 consecutive weeks, 10 male elite WB athletes wore a triaxial accelerometer. The session rating of perceived exertion (sRPE) and athletes' quality of recovery were also measured. Results There were no significant differences ( p > 0.05) in any of the studied parameters between the 3 weeks leading up to the playoffs, the week of playoffs, and the week after playoffs. No significant relationship between training load, sleep parameters, and recovery values was detected. Discussion The WB competition does not affect sleep quantity and quality.
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A biorefinery process was developed for a freeze-dried pomace of calafate berries (Berberis microphylla). The process consisted of extraction of lipophilic components with supercritical CO2 (scCO2) and subsequent extraction of the residue with a pressurized mixture of ethanol/water (1:1 v/v). scCO2 extracted oil from the pomace, while pressurized liquid extraction generated a crude extract rich in phenols and a residue rich in fiber, proteins and minerals. Response surface analysis of scCO2 extraction suggested optimal conditions of 60 °C, 358.5 bar and 144.6 min to obtain a lipid extract yield of 11.15% (d.w.). The dark yellow oil extract contained a good ratio of ω6/ω3 fatty acids (1:1.2), provitamin E tocopherols (406.6 mg/kg), and a peroxide index of 8.6 meq O2/kg. Pressurized liquid extraction generated a polar extract with good phenolic content (33 mg gallic acid equivalents /g d.w.), anthocyanins (8 mg/g) and antioxidant capacity (2,2-diphenyl-1-picrylhydrazyl test = 25 µg/mL and antioxidant activity = 63 µM Te/g). The extraction kinetics of oil by scCO2 and phenolic compounds were optimally adjusted to the spline model (R2 = 0.989 and R2 = 0.999, respectively). The solid extracted residue presented a fiber content close to cereals (56.4% d.w.) and acceptable values of proteins (29.6% d.w.) and minerals (14.1% d.w.). These eco-friendly processes valorize calafate pomace as a source of ingredients for formulation of healthy foods, nutraceuticals and nutritional supplements.
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The objective of this work was to carry out a preliminary study of the fractionation by supercritical CO2 (sc-CO2) extraction of two varieties of Peruvian beans (Phaseolus vulgaris L.), white (WB) and red (RB), to obtain two novel products: an oil rich in essential fatty acids and tocopherols and a defatted flour with high nutritional value and amino acids. The extraction temperature and pressure were optimized using the response surface methodology (RSM) and the extraction kinetics were optimized using the Spline equation. The results revealed that the best extraction conditions for WB and RB were 396.36 Bar, 40.46 °C, with an efficiency of 1.65%; and 391.995 Bar, 44.00 °C, with an efficiency of 1.12%, respectively. The WB and RB oils presented a high degree of polyunsaturation (63.2 and 52.8%, respectively), with oleic, linoleic, and linolenic fatty acids prevailing. Gamma-tocopherol was the predominant antioxidant in both oils. The residual flours (WB and RB) obtained after extraction with sc-CO2 had a high average content of proteins (23%), carbohydrates (61%), and minerals (3%). The limiting amino acids of WB were: Fen + Tyr, Leu, Lys, and in RB, only Leu was limiting. The viscosity of the solutions (20%) of the WB and RB flours mainly adjusted to the Waele's Ostwald model (r = 0.988). It is concluded that both products (oil and bean flour) obtained in an optimized manner using an eco-friendly technology with sc-CO2 have high nutrient and bioactive component content and can be used in the development of new ingredients and healthy foods of plant origin.
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Background: Poly(adenosine diphosphate-ribose) polymerase inhibitors (PARPi) improve progression free survival among patients with HER2 negative (HER2-ve) advanced breast cancer (ABC) and a BRCA1 or BRCA2 mutation compared to chemotherapy (CT). The objective of this prospective study was to evaluate the clinical benefit of PARPi treatment in terms of response, outcomes and survival by breast cancer type and treatment in a Latin-American population. Methods: From September 2019 to April 2023, we analyzed the data of patients with HER2-ve ABC with germline and/or somatic mutation of BRCA1 or BRCA2, or in the homologous recombination repair genes, treated with olaparib or talazoparib in daily clinical practice by oncologist from Argentina and México. real-world objective response rate (rwORR), best response rate, real-world progression-free survival (rwPFS) and real-world overall survival (rwOS) were analysed with R software and RStudio version 14.0. Results: After a median follow-up of 18.07 months (95% CI 10.53-30.07), 51 patients were treated with PARPi. Mean age at starting treatment was 47.08 years. 62.7% had ER + ve/HER2-ve and 35.3% had triple negative breast cancer (TNBC). 62.7% and 37.3% of patients received talazoparib and olaparib, respectively. BRCA 1 and 2 germline mutations were the most common alterations found in 96% of patients. 37.5% of patients received platinum-based CT in the (neo)adjuvant/metastatic setting. At the time to starting PARPi treatment, 57.5% had visceral metastasis, the median number of metastatic sites was 2 (range 1-4), the median number of lines was 2 (range 0-8), and 23.5% and 31.4% received PARPi in the 1st line and 2nd line, respectively.The rwORR was 47.0%, and the median real-world progression-free survival-1 (rwPFS1) was 7.77 months (95% CI 5.67-14.7). There was a tendency of better rwPFS1 in patients with versus without previous CT in the advance setting, 6.37 months (95% CI 5.03-8.73) and 14.30 months (95% CI 6.47-NR), respectively (p 0.084). The median rwOS was 26.97 months (95% CI 13.50-NR) and higher in the subgroup of patients naïve for CT versus previous exposure to CT in the advance setting, the median rwOS was 32.1 months (95% CI 27.0-NR) versus 13.0 (95% CI10.1-NR), respectively (p 0.022). The medium real-world progression-free survival-2 (next treatment after PARPi failure) was 4.00 months (95% CI 3.43-7.13). Treatment was discontinued due to adverse events in 4.0% of patients. Conclusion: This is the first evidence in a Latin-American population that replicates the data already published in randomised clinical trials and other scanty real-world evidence studies in this field, showing positive results in rwORR and rwPFS, and encouraging data in rwOS. Notably, there was a high proportion of patients with visceral progression even with visceral crisis and need for CT. Interestingly, there were similar rwOS results among subgroups (TNBC versus ER + ve/HER2-ve, talazoparib versus olaparib, etc).
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The tropical montane cloud forest is the most diverse and threatened vegetation type in Mexico. In the last decade, the number of described Ascomycetes species has notably increased, reaching more than 1300 species. This study describes six new species based on their molecular and morphological characteristics. Our results suggest that Mexico has the highest number of described species in the Neotropics. However, many other Mexican lineages still need to be described.
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Two new species of sequestrate fungi are described from south Mexico based on morphological and molecular evidences. Here we describe Elaphomycescastilloi characterized by the yellowish mycelial mat, dull blue gleba and ascospores of 9.7-11.5 µm; Entolomasecotioides is characterized by the secotioid basidiomata, sulcate, pale cream pileus, and basidiospores of 7-13 × 5-9 µm. Both species grow in montane cloud forest under Quercus sp. in the state of Chiapas, Mexico. Descriptions, photographs, and multilocus phylogeny for both species are presented.