An intensive isolation program carried out in three replicated composting piles allowed the identification of the resident and transient components of the composting microbiome. More than 4000 ...bacterial strains were isolated, enzymatically characterized and identified by partial sequencing of their 16S rRNA gene. While microorganisms isolated under mesophilic conditions were prominent throughout the process, thermophilic stages gathered the highest total counts and spore-forming bacteria prevailed at the bio-oxidative phase of composting. Enzymatic capabilities related to the degradation of polymeric materials were exhibited by most of the isolates and as a result of these activities, more soluble compounds could be made available to the entire composting microbiota. A high proportion of isolates showed to be thermotolerant as they were detected at mesophilic and thermophilic phases. Isolated strains belonged to 187 bacterial species. Biodiversity was greater at the central stages of composting and mesophilic, thermophilic and cooling phases shared 50% of species.
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•Intense turnover of organic matter was induced by inoculation of composting piles.•More simple compounds were released from polymeric fractions in inoculated piles.•Humification was ...more intense and earlier achieved in inoculated piles.•Inoculation clearly stimulated growth and activity of the composting microbiota.•Inoculation affected microbiota structure but its functionality remained unaltered.
Enhanced organic matter turnover was detected in lignocellulosic composting piles inoculated with microorganisms specifically capable of decomposing polymeric compounds. In comparison to uninoculated piles, the following results were obtained in the inoculated piles: degradation of hemicellulose, cellulose and lignin were 28%, 21% and 25% respectively higher. Total organic matter, total sugars and phenolic compounds also decreased more intensely. Greater amounts of soluble organic carbon, reducing sugars and soluble proteins were available to the composting microbiota. Recycling of organic to inorganic nitrogen was improved and humification was more intense and earlier attained. Microbial community structure was also affected by inoculation. It was initially thought that these effects were due to enzymatic capabilities of inoculants, however, microbial counts, especially those corresponding to functional groups, revealed that inoculation induced a true stimulation of microbial growth and activity in the entire composting microbiota which was actually responsible for all the beneficial effects reported here.
ABSTRACT
Studies of the kinematics and chemical compositions of Galactic globular clusters (GCs) enable the reconstruction of the history of star formation, chemical evolution, and mass assembly of ...the Galaxy. Using the latest data release (DR16) of the SDSS/APOGEE survey, we identify 3090 stars associated with 46 GCs. Using a previously defined kinematic association, we break the sample down into eight separate groups and examine how the kinematics-based classification maps into chemical composition space, considering only α (mostly Si and Mg) elements and Fe. Our results show that (i) the loci of both in situ and accreted subgroups in chemical space match those of their field counterparts; (ii) GCs from different individual accreted subgroups occupy the same locus in chemical space. This could either mean that they share a similar origin or that they are associated with distinct satellites which underwent similar chemical enrichment histories; (iii) the chemical compositions of the GCs associated with the low orbital energy subgroup defined by Massari and collaborators is broadly consistent with an in situ origin. However, at the low-metallicity end, the distinction between accreted and in situ populations is blurred; (iv) regarding the status of GCs whose origin is ambiguous, we conclude the following: the position in Si–Fe plane suggests an in situ origin for Liller 1 and a likely accreted origin for NGC 5904 and NGC 6388. The case of NGC 288 is unclear, as its orbital properties suggest an accretion origin, its chemical composition suggests it may have formed in situ.
Many alternatives for the proper disposal of horticultural plant wastes have been studied, and composting is one of the most attractive due to its insignificant environmental impact and low cost. The ...quality of compost for agronomical use is related to the degree of organic matter maturation and stabilization. Traditional parameters as well as temperature, ratio C/N, cationic exchange capacity, extractable carbon, or evolution of humificated substances have been successfully used to assess compost maturity and stability. However, microorganisms frequently isolated during composting release a wide range of hydrolytic enzymes, whose activity could apparently give interesting information on the rate of decomposition of organic matter and, therefore, on the product stability. The aim of this work was to study the evolution of some important enzymatic activities during composting of agricultural wastes and their comparison with other chemical parameters commonly employed as quality and maturity indexes, to establish a relationship between the degradation intensity of specific organic carbon fractions throughout the process. In this work, the chemical and biochemical parameters of plant wastes were studied along a composting process of 189 days to evaluate their importance as tools for compost characterization. Results showed an intense enzymatic activity during the first 2–3 weeks of composting (bio-oxidative phase), because of the availability of easily decomposable organic compounds. From a biological point of view, a less intense phase was observed between second and third month of composting (mesophilic or cooling phase). Finally, chemical humification parameters were more closely associated with the period between 119 and 189 days (maturation phase). Significant correlations between the enzymatic activities as well as between enzyme activities and other more traditional parameters were also highlighted, indicating that both kind of indexes can be a reliable tool to determine the degree of stability and maturation of horticultural plant wastes based-compost.
•Enzymatic and temperature patterns registered inside the pile are directly related.•Enzymatic activity reaches its peak during the first days of the composting process.•When piles begin to cool, the enzymatic activity decreases noticeably.•The intensity of the enzymatic activity indirectly affects the humification process.
We present the first catalog of gamma-ray sources emitting above 56 and 100 TeV with data from the High Altitude Water Cherenkov Observatory, a wide field-of-view observatory capable of detecting ...gamma rays up to a few hundred TeV. Nine sources are observed above 56 TeV, all of which are likely galactic in origin. Three sources continue emitting past 100 TeV, making this the highest-energy gamma-ray source catalog to date. We report the integral flux of each of these objects. We also report spectra for three highest-energy sources and discuss the possibility that they are PeVatrons.
Community structure, population dynamics and diversity of fungi were monitored in a full-scale membrane bioreactor (MBR) operated throughout four experimental phases (Summer 2009, Autumn 2009, Summer ...2010 and Winter, 2012) under different conditions, using the 18S-rRNA gene and the intergenic transcribed spacer (ITS2-region) as molecular markers, and a combination of temperature-gradient gel electrophoresis and 454-pyrosequencing. Both total and metabolically-active fungal populations were fingerprinted, by amplification of molecular markers from community DNA and retrotranscribed RNA, respectively. Fingerprinting and 454-pyrosequencing evidenced that the MBR sheltered a dynamic fungal community composed of a low number of species, in accordance with the knowledge of fungal diversity in freshwater environments, and displaying a medium-high level of functional organization with few numerically dominant phylotypes. Population shifts were experienced in strong correlation with the changes of environmental variables and operation parameters, with pH contributing the highest level of explanation. Phylotypes assigned to nine different fungal Phyla were detected, although the community was mainly composed of Ascomycota, Basidiomycota and Chytridiomycota/Blastocladiomycota. Prevailing fungal phylotypes were affiliated to Saccharomycetes and Chytridiomycetes/Blastocladiomycetes, which displayed antagonistic trends in their relative abundance throughout the experimental period. Fungi identified in the activated sludge were closely related to genera of relevance for the degradation of organic matter and trace-organic contaminants, as well as genera of dimorphic fungi potentially able to produce plant operational issues such as foaming or biofouling. Phylotypes closely related to genera of human and plant pathogenic fungi were also detected.
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•The MBR sheltered a dynamic fungal community composed of a low number of species.•Ascomycota, Basidiomycota and Chytridiomycota/Blastocladiomycota were most abundant.•Population shifts correlated strongly with changes of external abiotic variables.•Phylotypes related to both human and plant pathogenic fungi were detected.
Quantifying habitat use is important for understanding how animals meet their requirements for survival and provides information for conservation planning. Currently, assessments of range-wide ...habitat use that delimit species distributions are incomplete for many taxa. The Harpy Eagle (Harpia harpyja) is a raptor of conservation concern, widely distributed across Neotropical lowland forests, that currently faces threats from habitat loss and fragmentation. Here, we use penalized logistic regression to identify species-habitat associations and predict habitat suitability based on a new International Union for the Conservation of Nature range metric, termed Area of Habitat. From the species-habitat model, we performed a gap analysis to identify areas of high habitat suitability in regions with limited coverage in the key biodiversity area (KBA) network. Range-wide habitat use indicated that Harpy Eagles prefer areas of 70%–75% evergreen forest cover, low elevation, and high vegetation species richness. Conversely, Harpy Eagles avoid areas of >10% cultivated landcover and mosaic forest, and topographically complex areas. Our species-habitat model identified a large continuous area of potential habitat across the pan-Amazonia region, and a habitat corridor from the Chocó-Darién ecoregion of Colombia running north along the Caribbean coast of Central America. Little habitat was predicted across the Atlantic Forest biome, which is now severely degraded. The current KBA network covered 18% of medium to high Harpy Eagle habitat exceeding a target biodiversity area representation of 10%, based on species range size. Four major areas of high suitability habitat lacking coverage in the KBA network were identified in north and west Colombia, western Guyana, and north-west Brazil. We recommend these multiple gaps of habitat as new KBAs for strengthening the current KBA network. Modeled area of habitat estimates as described here is a useful tool for large-scale conservation planning and can be readily applied to many taxa. LAY SUMMARY Quantifying habitat use is key to understanding animals' requirements for survival and can inform spatial conservation planning by mapping species range limits. Species that inhabit remote, hard-to-survey areas lack sufficient location data and there is a need to be able to predict into poorly sampled areas to estimate the potential area of habitat. Using species distribution models, we identified Harpy Eagle range limits, habitat area, and key biodiversity area coverage across the species range. Harpy Eagles prefer areas of 70–75% evergreen forest cover, high vegetation species richness, and low elevation. Key biodiversity areas covered 18% of highly suitable Harpy Eagle habitat but with key gaps in coverage in north and west Colombia, western Guyana, and north-west Brazil. Our method of calculating habitat area estimates based on a predictive spatial model is a useful tool for large-scale conservation planning and can be readily applied to many taxa. Cuantificar el uso de hábitat es importante para comprender cómo los animales alcanzan sus requerimientos para la supervivencia, y proporciona información para la planificación de la conservación. En la actualidad, las evaluaciones del uso de hábitat a lo largo de todo el rango que delimitan las distribuciones de las especies están incompletas para muchos taxones. Harpia harpyja es una rapaz de preocupación para la conservación, ampliamente distribuida en los bosques neotropicales de tierras bajas, que actualmente enfrenta amenazas por la pérdida y fragmentación de hábitat. Aquí, utilizamos una regresión logística penalizada para identificar asociaciones de especies y hábitats y predecir la aptitud del hábitat basados en una nueva métrica de rango de la Unión Internacional para la Conservación de la Naturaleza, denominada Área de Hábitat. A partir del modelo de especie-hábitat, realizamos un análisis de brechas para identificar áreas de alta aptitud de hábitat en regiones con cobertura limitada en la red de Áreas Clave para la Biodiversidad (ACB). El uso de hábitat en todo su rango de distribución indicó que H. harpyja prefiere áreas con 70–75% de cobertura forestal siempre verde, baja elevación y gran riqueza de especies de vegetación. Por el contrario, H. harpyja evita áreas con más del 10% de cobertura terrestre cultivada y bosques en mosaico, y áreas topográficamente complejas. Nuestro modelo de especie-hábitat identificó una gran área continua de hábitat potencial a lo largo de la región panamazónica, y un corredor de hábitat desde la ecorregión de Chocó-Darién de Colombia que se extiende hacia el norte a lo largo de la costa caribeña de América Central. Se predijo poco hábitat en el bioma del Bosque Atlántico, que ahora está severamente degradado. La red actual de ACB cubrió el 18% del hábitat medio a alto de H. harpyja, lo que excedió la representación del área de biodiversidad objetivo del 10%, según el tamaño del rango de la especie. Se identificaron cuatro áreas principales de hábitat de alta aptitud que no están cubiertas por la red ACB en el norte y oeste de Colombia, el oeste de Guyana y el noroeste de Brasil. Recomendamos que estos múltiples vacíos de hábitat se incluyan como nuevas áreas para fortalecer la red actual de ACB. Las estimaciones del área de hábitat modelada como se describe aquí son una herramienta útil para la planificación de la conservación a gran escala y se pueden aplicar fácilmente a muchos taxones.
Several scoring systems predict mortality in alcohol-associated hepatitis (AH), including the Maddrey discriminant function (mDF) and model for end-stage liver disease (MELD) score developed in the ...United States, Glasgow alcoholic hepatitis score in the United Kingdom, and age, bilirubin, international normalized ratio, and creatinine score in Spain. To date, no global studies have examined the utility of these scores, nor has the MELD-sodium been evaluated for outcome prediction in AH. In this study, we assessed the accuracy of different scores to predict short-term mortality in AH and investigated additional factors to improve mortality prediction.
Patients admitted to hospital with a definite or probable AH were recruited by 85 tertiary centers in 11 countries and across 3 continents. Baseline demographic and laboratory variables were obtained. The primary outcome was all-cause mortality at 28 and 90 days.
In total, 3,101 patients were eligible for inclusion. After exclusions (n = 520), 2,581 patients were enrolled (74.4% male, median age 48 years, interquartile range 40.9-55.0 years). The median MELD score was 23.5 (interquartile range 20.5-27.8). Mortality at 28 and 90 days was 20% and 30.9%, respectively. The area under the receiver operating characteristic curve for 28-day mortality ranged from 0.776 for MELD-sodium to 0.701 for mDF, and for 90-day mortality, it ranged from 0.773 for MELD to 0.709 for mDF. The area under the receiver operating characteristic curve for mDF to predict death was significantly lower than all other scores. Age added to MELD obtained only a small improvement of AUC.
These results suggest that the mDF score should no longer be used to assess AH's prognosis. The MELD score has the best performance in predicting short-term mortality.
This study aimed to develop Ca2+ doped ZnO nanoparticles (NPs) and investigate their antibacterial properties against microorganisms of dental interest. Zn-Ca NPs were synthesized by the sol-gel ...method with different concentrations of Ca2+ (1, 3, and 5 wt. %) and subsequently characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), UV-vis spectroscopy and Fourier transform infrared spectroscopy (FT-IR). The Kirby–Bauer method was used to measure antibacterial effects. NPs showed the wurzite phase of ZnO and bandgap energies (Eg) from 2.99 to 3.04 eV. SEM analysis showed an average particle size of 80 to 160 nm. The treatments that presented the best antibacterial activity were Zn-Ca 3% and Zn-Ca 5%. ZnO NPs represent an alternative to generate and improve materials with antibacterial capacity for dental applications.
Because of the high energies and long distances to the sources, astrophysical observations provide a unique opportunity to test possible signatures of Lorentz invariance violation (LIV). Superluminal ...LIV enables the decay of photons at high energy. The high altitude water Cherenkov (HAWC) observatory is among the most sensitive gamma-ray instruments currently operating above 10 TeV. HAWC finds evidence of 100 TeV photon emission from at least four astrophysical sources. These observations exclude, for the strongest of the limits set, the LIV energy scale to 2.2×10^{31} eV, over 1800 times the Planck energy and an improvement of 1 to 2 orders of magnitude over previous limits.
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