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2.
J Am Coll Surg ; 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38722036

RESUMO

INTRODUCTION: The lack of consensus on equity measurement and its incorporation into quality-assessment programs at the hospital and system levels may be a barrier to addressing disparities in surgical care. This study aimed to identify population-level and within-hospital differences in the quality of surgical care provision. METHODS: The analysis included 657 National Surgical Quality Improvement Program participating hospitals with over 4 million patients (2014-2018). Multi-level random slope, random intercept modeling was used to examine for population-level and in-hospital disparities. Disparities in surgical care by Area Deprivation Index (ADI), race, and ethnicity were analyzed for five measures: all-case inpatient mortality, all-case urgent readmission, all-case postoperative surgical site infection, colectomy mortality, and spine surgery complications. RESULTS: Population-level disparities were identified across all measures by ADI, two measures for Black race (all-case readmissions and spine surgery complications), and none for Hispanic ethnicity. Disparities remained significant in the adjusted models. Prior to risk-adjustment, in all measures examined, within-hospital disparities were detected in: 25.8-99.8% of hospitals for ADI, 0-6.1% of hospitals for Black race, and 0-0.8% of hospitals for Hispanic ethnicity. Following risk-adjustment, in all measures examined, fewer than 1.1% of hospitals demonstrated disparities by ADI, race, or ethnicity. CONCLUSIONS: Following risk adjustment, very few hospitals demonstrated significant disparities in care. Disparities were more frequently detected by ADI than by race and ethnicity. The lack of substantial in-hospital disparities may be due to the use of postoperative metrics, small sample sizes, the risk adjustment methodology, and healthcare segregation. Further work should examine surgical access and healthcare segregation.

3.
Microbiol Resour Announc ; 13(6): e0003324, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38651910

RESUMO

Rivers are critical ecosystems that impact global biogeochemical cycles. Nonetheless, a mechanistic understanding of river microbial metabolisms and their influences on geochemistry is lacking. Here, we announce metaproteomes of river sediments that are paired with metagenomes and metabolites, enabling an understanding of the microbial underpinnings of river respiration.

4.
mSystems ; 9(1): e0069823, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38063415

RESUMO

While wetlands are major sources of biogenic methane (CH4), our understanding of resident microbial metabolism is incomplete, which compromises the prediction of CH4 emissions under ongoing climate change. Here, we employed genome-resolved multi-omics to expand our understanding of methanogenesis in the thawing permafrost peatland of Stordalen Mire in Arctic Sweden. In quadrupling the genomic representation of the site's methanogens and examining their encoded metabolism, we revealed that nearly 20% of the metagenome-assembled genomes (MAGs) encoded the potential for methylotrophic methanogenesis. Further, 27% of the transcriptionally active methanogens expressed methylotrophic genes; for Methanosarcinales and Methanobacteriales MAGs, these data indicated the use of methylated oxygen compounds (e.g., methanol), while for Methanomassiliicoccales, they primarily implicated methyl sulfides and methylamines. In addition to methanogenic methylotrophy, >1,700 bacterial MAGs across 19 phyla encoded anaerobic methylotrophic potential, with expression across 12 phyla. Metabolomic analyses revealed the presence of diverse methylated compounds in the Mire, including some known methylotrophic substrates. Active methylotrophy was observed across all stages of a permafrost thaw gradient in Stordalen, with the most frozen non-methanogenic palsa found to host bacterial methylotrophy and the partially thawed bog and fully thawed fen seen to house both methanogenic and bacterial methylotrophic activities. Methanogenesis across increasing permafrost thaw is thus revised from the sole dominance of hydrogenotrophic production and the appearance of acetoclastic at full thaw to consider the co-occurrence of methylotrophy throughout. Collectively, these findings indicate that methanogenic and bacterial methylotrophy may be an important and previously underappreciated component of carbon cycling and emissions in these rapidly changing wetland habitats.IMPORTANCEWetlands are the biggest natural source of atmospheric methane (CH4) emissions, yet we have an incomplete understanding of the suite of microbial metabolism that results in CH4 formation. Specifically, methanogenesis from methylated compounds is excluded from all ecosystem models used to predict wetland contributions to the global CH4 budget. Though recent studies have shown methylotrophic methanogenesis to be active across wetlands, the broad climatic importance of the metabolism remains critically understudied. Further, some methylotrophic bacteria are known to produce methanogenic by-products like acetate, increasing the complexity of the microbial methylotrophic metabolic network. Prior studies of Stordalen Mire have suggested that methylotrophic methanogenesis is irrelevant in situ and have not emphasized the bacterial capacity for metabolism, both of which we countered in this study. The importance of our findings lies in the significant advancement toward unraveling the broader impact of methylotrophs in wetland methanogenesis and, consequently, their contribution to the terrestrial global carbon cycle.


Assuntos
Euryarchaeota , Pergelissolo , Ecossistema , Bactérias/genética , Áreas Alagadas , Euryarchaeota/metabolismo , Metano/metabolismo
6.
J Am Acad Dermatol ; 90(1): 91-97, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37758026

RESUMO

BACKGROUND: Keratinocyte carcinoma (KC) is the commonest type of malignancy in humans; however, the impact of KC on survival is poorly understood. OBJECTIVES: This study characterizes the impact of basal cell carcinoma (BCC), squamous cell carcinoma (SCC), and squamous cell carcinoma in situ (SCCis) on the survival of Icelanders. METHODS: This whole population study evaluated relative survival of KC in Iceland by using a cancer registry containing records of all BCC, SCCis, and SCC cases recorded in Iceland between 1981 and 2015. RESULTS: Between 1981 and 2015, 8767 Icelanders were diagnosed with their first localized KC. A total of 6473 individuals with BCC, 1194 with SCCis, and 1100 with invasive SCC, respectively. BCC was not associated with decreased survival except for men diagnosed with BCC between 1981 and 1995 for whom decreased 10-year relative survival was observed (85.3, 95% CI [77.9-92.7]). SCC and SCCis were both associated with a decrease in relative survival for certain population subgroups such as individuals <50 years of age at time of diagnosis. CONCLUSION: Our whole population cohort survival study examining the Icelandic Cancer Registry supports prior studies demonstrating that BCC is not associated with a reduction in relative survival and that SCC and SCCis are associated with comparatively poor relative survival in certain population subgroups.


Assuntos
Carcinoma Basocelular , Carcinoma de Células Escamosas , Neoplasias Cutâneas , Masculino , Humanos , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/patologia , Carcinoma Basocelular/epidemiologia , Carcinoma Basocelular/patologia , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/patologia , Estudos de Coortes , Queratinócitos/patologia
7.
PLoS One ; 18(12): e0287943, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38153952

RESUMO

Since industrialization began, atmospheric CO2 ([CO2]) has increased from 270 to 415 ppm and is projected to reach 800-1000 ppm this century. Some Arabidopsis thaliana (Arabidopsis) genotypes delayed flowering in elevated [CO2] relative to current [CO2], while others showed no change or accelerations. To predict genotype-specific flowering behaviors, we must understand the mechanisms driving flowering response to rising [CO2]. [CO2] changes alter photosynthesis and carbohydrates in plants. Plants sense carbohydrate levels, and exogenous carbohydrate application influences flowering time and flowering transcript levels. We asked how organismal changes in carbohydrates and transcription correlate with changes in flowering time under elevated [CO2]. We used a genotype (SG) of Arabidopsis that was selected for high fitness at elevated [CO2] (700 ppm). SG delays flowering under elevated [CO2] (700 ppm) relative to current [CO2] (400 ppm). We compared SG to a closely related control genotype (CG) that shows no [CO2]-induced flowering change. We compared metabolomic and transcriptomic profiles in these genotypes at current and elevated [CO2] to assess correlations with flowering in these conditions. While both genotypes altered carbohydrates in response to elevated [CO2], SG had higher levels of sucrose than CG and showed a stronger increase in glucose and fructose in elevated [CO2]. Both genotypes demonstrated transcriptional changes, with CG increasing genes related to fructose 1,6-bisphosphate breakdown, amino acid synthesis, and secondary metabolites; and SG decreasing genes related to starch and sugar metabolism, but increasing genes involved in oligosaccharide production and sugar modifications. Genes associated with flowering regulation within the photoperiod, vernalization, and meristem identity pathways were altered in these genotypes. Elevated [CO2] may alter carbohydrates to influence transcription in both genotypes and delayed flowering in SG. Changes in the oligosaccharide pool may contribute to delayed flowering in SG. This work extends the literature exploring genotypic-specific flowering responses to elevated [CO2].


Assuntos
Arabidopsis , Arabidopsis/metabolismo , Dióxido de Carbono/metabolismo , Genótipo , Carboidratos , Oligossacarídeos/metabolismo , Açúcares/metabolismo , Regulação da Expressão Gênica de Plantas , Flores/metabolismo , Folhas de Planta/metabolismo
8.
ISME J ; 17(12): 2326-2339, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37880541

RESUMO

In many anoxic environments, syntrophic acetate oxidation (SAO) is a key pathway mediating the conversion of acetate into methane through obligate cross-feeding interactions between SAO bacteria (SAOB) and methanogenic archaea. The SAO pathway is particularly important in engineered environments such as anaerobic digestion (AD) systems operating at thermophilic temperatures and/or with high ammonia. Despite the widespread importance of SAOB to the stability of the AD process, little is known about their in situ physiologies due to typically low biomass yields and resistance to isolation. Here, we performed a long-term (300-day) continuous enrichment of a thermophilic (55 °C) SAO community from a municipal AD system using acetate as the sole carbon source. Over 80% of the enriched bioreactor metagenome belonged to a three-member consortium, including an acetate-oxidizing bacterium affiliated with DTU068 encoding for carbon dioxide, hydrogen, and formate production, along with two methanogenic archaea affiliated with Methanothermobacter_A. Stable isotope probing was coupled with metaproteogenomics to quantify carbon flux into each community member during acetate conversion and inform metabolic reconstruction and genome-scale modeling. This effort revealed that the two Methanothermobacter_A species differed in their preferred electron donors, with one possessing the ability to grow on formate and the other only consuming hydrogen. A thermodynamic analysis suggested that the presence of the formate-consuming methanogen broadened the environmental conditions where ATP production from SAO was favorable. Collectively, these results highlight how flexibility in electron partitioning during SAO likely governs community structure and fitness through thermodynamic-driven mutualism, shedding valuable insights into the metabolic underpinnings of this key functional group within methanogenic ecosystems.


Assuntos
Ecossistema , Euryarchaeota , Anaerobiose , Elétrons , Acetatos/metabolismo , Bactérias , Archaea , Euryarchaeota/metabolismo , Oxirredução , Hidrogênio/metabolismo , Formiatos/metabolismo , Metano/metabolismo
9.
J Am Coll Surg ; 237(6): 856-861, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37703495

RESUMO

BACKGROUND: Disparity in surgical care impedes the delivery of uniformly high-quality care. Metrics that quantify disparity in care can help identify areas for needed intervention. A literature-based Disparity-Sensitive Score (DSS) system for surgical care was adapted by the Metrics for Equitable Access and Care in Surgery (MEASUR) group. The alignment between the MEASUR DSS and Delphi ratings of an expert advisory panel (EAP) regarding the disparity sensitivity of surgical quality metrics was assessed. STUDY DESIGN: Using DSS criteria MEASUR co-investigators scored 534 surgical metrics which were subsequently rated by the EAP. All scores were converted to a 9-point scale. Agreement between the new measurement technique (ie DSS) and an established subjective technique (ie importance and validity ratings) were assessed using the Bland-Altman method, adjusting for the linear relationship between the paired difference and the paired average. The limit of agreement (LOA) was set at 1.96 SD (95%). RESULTS: The percentage of DSS scores inside the LOA was 96.8% (LOA, 0.02 points) for the importance rating and 94.6% (LOA, 1.5 points) for the validity rating. In comparison, 94.4% of the 2 subjective EAP ratings were inside the LOA (0.7 points). CONCLUSIONS: Applying the MEASUR DSS criteria using available literature allowed for identification of disparity-sensitive surgical metrics. The results suggest that this literature-based method of selecting quality metrics may be comparable to more complex consensus-based Delphi methods. In fields with robust literature, literature-based composite scores may be used to select quality metrics rather than assembling consensus panels.


Assuntos
Benchmarking , Qualidade da Assistência à Saúde , Humanos , Técnica Delphi , Consenso
10.
mBio ; 14(5): e0151123, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37695138

RESUMO

IMPORTANCE: One of the most-cited examples of the gut microbiome modulating human disease is the microbial metabolism of quaternary amines from protein-rich foods. By-products of this microbial processing promote atherosclerotic heart disease, a leading cause of human mortality globally. Our research addresses current knowledge gaps in our understanding of this microbial metabolism by holistically inventorying the microorganisms and expressed genes catalyzing critical atherosclerosis-promoting and -ameliorating reactions in the human gut. This led to the creation of an open-access resource, the Methylated Amine Gene Inventory of Catabolism database, the first systematic inventory of gut methylated amine metabolism. More importantly, using this resource we deliver here, we show for the first time that these gut microbial genes can predict human disease, paving the way for microbiota-inspired diagnostics and interventions.


Assuntos
Doenças Cardiovasculares , Microbioma Gastrointestinal , Microbiota , Humanos , Doenças Cardiovasculares/genética , Aminas , Genes Microbianos , Metilaminas/metabolismo
11.
Pediatr Blood Cancer ; 70(11): e30620, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37555297

RESUMO

As non-operative management of acute appendicitis in children has become more common, missed incidental appendiceal pathology can be an unintended consequence. We assessed the prevalence of neuroendocrine tumors in appendectomy specimens from eight US children's hospitals from 2012 to 2021. The prevalence of neuroendocrine tumors (NET) was found to be 1:271, with a median age of 14 years and 62% female. Most tumors were small (median 6 mm; interquartile range [IQR]: 3-10), and no recurrence was noted during the follow-up period (median 22.5 months; IQR: 3-53). The possibility of delayed diagnosis of these tumors should be part of the discussion for non-operative management of pediatric acute appendicitis.


Assuntos
Neoplasias do Apêndice , Apendicite , Laparoscopia , Tumores Neuroendócrinos , Humanos , Criança , Feminino , Estados Unidos/epidemiologia , Adolescente , Masculino , Apendicectomia , Apendicite/epidemiologia , Apendicite/cirurgia , Apendicite/diagnóstico , Tumores Neuroendócrinos/epidemiologia , Tumores Neuroendócrinos/cirurgia , Tumores Neuroendócrinos/patologia , Prevalência , Neoplasias do Apêndice/epidemiologia , Neoplasias do Apêndice/cirurgia , Doença Aguda , Estudos Retrospectivos
12.
Sci Total Environ ; 899: 165689, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37481084

RESUMO

Plant-soil-microbe interactions are crucial for driving rhizosphere processes that contribute to metabolite turnover and nutrient cycling. With the increasing frequency and severity of water scarcity due to climate warming, understanding how plant-mediated processes, such as root exudation, influence soil organic matter turnover in the rhizosphere is essential. In this study, we used 16S rRNA gene amplicon sequencing, rhizosphere metabolomics, and position-specific 13C-pyruvate labeling to examine the effects of three different plant species (Piper auritum, Hibiscus rosa sinensis, and Clitoria fairchildiana) and their associated microbial communities on soil organic carbon turnover in the rhizosphere. Our findings indicate that in these tropical plants, the rhizosphere metabolome is primarily shaped by the response of roots to drought rather than direct shifts in the rhizosphere bacterial community composition. Specifically, the reduced exudation of plant roots had a notable effect on the metabolome of the rhizosphere of P. auritum, with less reliance on neighboring microbes. Contrary to P. auritum, H. rosa sinensis and C. fairchildiana experienced changes in their exudate composition during drought, causing alterations to the bacterial communities in the rhizosphere. This, in turn, had a collective impact on the rhizosphere's metabolome. Furthermore, the exclusion of phylogenetically distant microbes from the rhizosphere led to shifts in its metabolome. Additionally, C. fairchildiana appeared to be associated with only a subset of symbiotic bacteria under drought conditions. These results indicate that plant species-specific microbial interactions systematically change with the root metabolome. As roots respond to drought, their associated microbial communities adapt, potentially reinforcing the drought tolerance strategies of plant roots. These findings have significant implications for maintaining plant health and preference during drought stress and improving plant performance under climate change.


Assuntos
Floresta Úmida , Microbiologia do Solo , Secas , Rizosfera , RNA Ribossômico 16S/genética , Carbono/metabolismo , Solo , Bactérias/metabolismo , Metaboloma , Raízes de Plantas/metabolismo
13.
Nat Microbiol ; 8(8): 1480-1494, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37524975

RESUMO

Drought impacts on microbial activity can alter soil carbon fate and lead to the loss of stored carbon to the atmosphere as CO2 and volatile organic compounds (VOCs). Here we examined drought impacts on carbon allocation by soil microbes in the Biosphere 2 artificial tropical rainforest by tracking 13C from position-specific 13C-pyruvate into CO2 and VOCs in parallel with multi-omics. During drought, efflux of 13C-enriched acetate, acetone and C4H6O2 (diacetyl) increased. These changes represent increased production and buildup of intermediate metabolites driven by decreased carbon cycling efficiency. Simultaneously,13C-CO2 efflux decreased, driven by a decrease in microbial activity. However, the microbial carbon allocation to energy gain relative to biosynthesis was unchanged, signifying maintained energy demand for biosynthesis of VOCs and other drought-stress-induced pathways. Overall, while carbon loss to the atmosphere via CO2 decreased during drought, carbon loss via efflux of VOCs increased, indicating microbially induced shifts in soil carbon fate.


Assuntos
Bactérias , Carbono , Secas , Floresta Úmida , Microbiologia do Solo , Carbono/metabolismo , Dióxido de Carbono/metabolismo , Solo/química , Clima Tropical , Bactérias/classificação , Bactérias/genética , Bactérias/metabolismo , Biodiversidade , Multiômica , Regulação Bacteriana da Expressão Gênica
14.
ChemSusChem ; 16(13): e202300157, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37222654

RESUMO

Efficient direct air capture (DAC) of CO2 will require strategies to deal with the relatively low concentration in the atmosphere. One such strategy is to employ the combination of a CO2 -selective membrane coupled with a CO2 capture solvent acting as a draw solution. Here, the interactions between a leading water-lean carbon-capture solvent, a polyether ether ketone (PEEK)-ionene membrane, CO2 , and combinations were probed using advanced NMR techniques coupled with advanced simulations. We identify the speciation and dynamics of the solvent, membrane, and CO2 , presenting spectroscopic evidence of CO2 diffusion through benzylic regions within the PEEK-ionene membrane, not spaces in the ionic lattice as expected. Our results demonstrate that water-lean capture solvents provide a thermodynamic and kinetic funnel to draw CO2 from the air through the membrane and into the bulk solvent, thus enhancing the performance of the membrane. The reaction between the carbon-capture solvent and CO2 produces carbamic acid, disrupting interactions between the imidazolium (Im+ ) cations and the bistriflimide anions within the PEEK-ionene membrane, thereby creating structural changes through which CO2 can diffuse more readily. Consequently, this restructuring results in CO2 diffusion at the interface that is faster than CO2 diffusion in the bulk carbon-capture solvent.


Assuntos
Dióxido de Carbono , Água , Solventes/química , Água/química , Dióxido de Carbono/química , Polietilenoglicóis
15.
Cureus ; 15(1): e34476, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36874688

RESUMO

Sports dermatology describes skin conditions occurring in athletes. We describe a man with callosities on his palmar hands and fingers secondary to pull-ups and review sports-related dermatoses involving the hands. A 42-year-old man presented with a several-year history of calluses on his palmar hands. The lesions correspond to areas of contact on his ventral hand with the pull-up bar; therefore, the condition is referred to as pull-up palms (PUP). Sports-related dermatoses affecting the hands include contact dermatitis, infections, lacerations, and mechanical trauma. Several of the sports-associated conditions of the hand are unique to a specific sport. Hand-associated sports dermatoses are reviewed.

16.
Glob Chang Biol ; 29(7): 1951-1970, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36740729

RESUMO

Peatlands are among the largest natural sources of atmospheric methane (CH4 ) worldwide. Microbial processes play a key role in regulating CH4 emissions from peatland ecosystems, yet the complex interplay between soil substrates and microbial communities in controlling CH4 emissions as a function of global change remains unclear. Herein, we performed an integrated analysis of multi-omics data sets to provide a comprehensive understanding of the molecular processes driving changes in greenhouse gas (GHG) emissions in peatland ecosystems with increasing temperature and sulfate deposition in a laboratory incubation study. We sought to first investigate how increasing temperatures (4, 21, and 35°C) impact soil microbiome-metabolome interactions; then explore the competition between methanogens and sulfate-reducing bacteria (SRBs) with increasing sulfate concentrations at the optimum temperature for methanogenesis. Our results revealed that peat soil organic matter degradation, mediated by biotic and potentially abiotic processes, is the main driver of the increase in CO2 production with temperature. In contrast, the decrease in CH4 production at 35°C was linked to the absence of syntrophic communities and the potential inhibitory effect of phenols on methanogens. Elevated temperatures further induced the microbial communities to develop high growth yield and stress tolerator trait-based strategies leading to a shift in their composition and function. On the other hand, SRBs were able to outcompete methanogens in the presence of non-limiting sulfate concentrations at 21°C, thereby reducing CH4 emissions. At higher sulfate concentrations, however, the prevalence of communities capable of producing sufficient low-molecular-weight carbon substrates for the coexistence of SRBs and methanogens was translated into elevated CH4 emissions. The use of omics in this study enhanced our understanding of the structure and interactions among microbes with the abiotic components of the system that can be useful for mitigating GHG emissions from peatland ecosystems in the face of global change.


Assuntos
Gases de Efeito Estufa , Gases de Efeito Estufa/análise , Solo/química , Temperatura , Ecossistema , Sulfatos/análise , Dióxido de Carbono/análise , Metano/análise , Óxido Nitroso/análise
17.
J Am Coll Surg ; 236(1): 135-143, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36111798

RESUMO

BACKGROUND: In the US, disparities in surgical care impede the delivery of uniformly high-quality care to all patients. There is a lack of disparity-sensitive measures related to surgical care. The American College of Surgeons Metrics for Equitable Access and Care in Surgery group, through research and expert consensus, aimed to identify disparity-sensitive measures in surgical care. STUDY DESIGN: An environmental scan, systematic literature review, and subspecialty society surveys were conducted to identify potential disparity-sensitive surgical measures. A modified Delphi process was conducted where panelists rated measures on both importance and validity. In addition, a novel literature-based disparity-sensitive scoring process was used. RESULTS: We identified 841 potential disparity-sensitive surgical measures. From these, our Delphi and literature-based approaches yielded a consensus list of 125 candidate disparity-sensitive measures. These measures were rated as both valid and important and were supported by the existing literature. CONCLUSION: There are profound disparities in surgical care within the US healthcare system. A multidisciplinary Delphi panel identified 125 potential disparity-sensitive surgical measures that could be used to track health disparities, evaluate the impact of focused interventions, and reduce healthcare inequity.


Assuntos
Qualidade da Assistência à Saúde , Humanos , Consenso , Técnica Delphi
18.
Langmuir ; 38(50): 15540-15551, 2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36469510

RESUMO

Several strategies for mitigating the build-up of atmospheric carbon dioxide (CO2) bring wet supercritical CO2 (scCO2) in contact with phyllosilicates such as illites and smectites. While some work has examined the role of the charge-balancing cation and smectite framework features on CO2/smectite interactions, to our knowledge no one has examined how the polarizability of the charge-balancing cation influences these behaviors. In this paper, the scCO2 adsorption properties of Pb2+, Rb+, and NH4+ saturated smectite clays at variable relative humidity are studied by integrating in situ high-pressure X-ray diffraction (XRD), infrared spectroscopic titrations, and magic angle spinning nuclear magnetic resonance (MAS NMR) methods. The results are combined with previously published data for Na+, Cs+, and Ca2+ saturated versions of the same smectites to isolate the roles of the charge-balancing cations and perform two independent tests of the role of charge-balancing cation polarizability in determining the interlayer fluid properties and smectite expansion. Independent correlations developed for (i) San Bernardino hectorite (SHCa-1) and (ii) Wyoming montmorillonite (SWy-2) both show that cation polarizability is important in predicting the interlayer composition (mol% CO2 in the interlayer fluid and CO2/cation ratio in interlayer) and the expansion behavior for smectites in contact with wet and dry scCO2. In particular, this study shows that the charge-balancing cation polarizability is the most important cation-associated parameter in determining the expansion of the trioctahedral smectite, hectorite, when in contact with dry scCO2. While both independent tests show that cation polarizability is an important factor in smectite-scCO2 systems, the correlations for hectorite are different from those determined for montmorillonite. The root of these differences is likely associated with the roles of the smectite framework on adsorption, warranting follow-up studies with a larger number of unique smectite frameworks. Overall, the results show that the polarizability of the charge-balancing cation should be considered when preparing smectite clays (or industrial processes involving smectites) to capture CO2 and in predicting the behavior of caprocks over time.

19.
JAMA Surg ; 157(11): 1067, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36001307

Assuntos
Médicos , Política , Humanos
20.
mSystems ; 7(4): e0051622, 2022 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-35861508

RESUMO

Rivers have a significant role in global carbon and nitrogen cycles, serving as a nexus for nutrient transport between terrestrial and marine ecosystems. Although rivers have a small global surface area, they contribute substantially to worldwide greenhouse gas emissions through microbially mediated processes within the river hyporheic zone. Despite this importance, research linking microbial and viral communities to specific biogeochemical reactions is still nascent in these sediment environments. To survey the metabolic potential and gene expression underpinning carbon and nitrogen biogeochemical cycling in river sediments, we collected an integrated data set of 33 metagenomes, metaproteomes, and paired metabolomes. We reconstructed over 500 microbial metagenome-assembled genomes (MAGs), which we dereplicated into 55 unique, nearly complete medium- and high-quality MAGs spanning 12 bacterial and archaeal phyla. We also reconstructed 2,482 viral genomic contigs, which were dereplicated into 111 viral MAGs (vMAGs) of >10 kb in size. As a result of integrating gene expression data with geochemical and metabolite data, we created a conceptual model that uncovered new roles for microorganisms in organic matter decomposition, carbon sequestration, nitrogen mineralization, nitrification, and denitrification. We show how these metabolic pathways, integrated through shared resource pools of ammonium, carbon dioxide, and inorganic nitrogen, could ultimately contribute to carbon dioxide and nitrous oxide fluxes from hyporheic sediments. Further, by linking viral MAGs to these active microbial hosts, we provide some of the first insights into viral modulation of river sediment carbon and nitrogen cycling. IMPORTANCE Here we created HUM-V (hyporheic uncultured microbial and viral), an annotated microbial and viral MAG catalog that captures strain and functional diversity encoded in these Columbia River sediment samples. Demonstrating its utility, this genomic inventory encompasses multiple representatives of dominant microbial and archaeal phyla reported in other river sediments and provides novel viral MAGs that can putatively infect these. Furthermore, we used HUM-V to recruit gene expression data to decipher the functional activities of these MAGs and reconstruct their active roles in Columbia River sediment biogeochemical cycling. Ultimately, we show the power of MAG-resolved multi-omics to uncover interactions and chemical handoffs in river sediments that shape an intertwined carbon and nitrogen metabolic network. The accessible microbial and viral MAGs in HUM-V will serve as a community resource to further advance more untargeted, activity-based measurements in these, and related, freshwater terrestrial-aquatic ecosystems.


Assuntos
Ecossistema , Rios , Dióxido de Carbono/metabolismo , Archaea/genética , Ciclo do Nitrogênio , Nitrogênio/metabolismo
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