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1.
Ecol Lett ; 27(7): e14469, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38990962

RESUMEN

The decline in global plant diversity has raised concerns about its implications for carbon fixation and global greenhouse gas emissions (GGE), including carbon dioxide (CO2), nitrous oxide (N2O) and methane (CH4). Therefore, we conducted a comprehensive meta-analysis of 2103 paired observations, examining GGE, soil organic carbon (SOC) and plant carbon in plant mixtures and monocultures. Our findings indicate that plant mixtures decrease soil N2O emissions by 21.4% compared to monocultures. No significant differences occurred between mixtures and monocultures for soil CO2 emissions, CH4 emissions or CH4 uptake. Plant mixtures exhibit higher SOC and plant carbon storage than monocultures. After 10 years of vegetation development, a 40% reduction in species richness decreases SOC content and plant carbon storage by 12.3% and 58.7% respectively. These findings offer insights into the intricate connections between plant diversity, soil and plant carbon storage and GGE-a critical but previously unexamined aspect of biodiversity-ecosystem functioning.


Asunto(s)
Biodiversidad , Carbono , Gases de Efecto Invernadero , Plantas , Suelo , Suelo/química , Gases de Efecto Invernadero/análisis , Carbono/metabolismo , Carbono/análisis , Plantas/metabolismo , Óxido Nitroso/análisis , Óxido Nitroso/metabolismo , Ecosistema , Dióxido de Carbono/metabolismo , Dióxido de Carbono/análisis , Metano/metabolismo , Efecto Invernadero
2.
PLoS One ; 19(7): e0306987, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38991027

RESUMEN

The laboratory-scale (in-vitro) microbial fermentation based on screening of process parameters (factors) and statistical validation of parameters (responses) using regression analysis. The recent trends have shifted from full factorial design towards more complex response surface methodology designs such as Box-Behnken design, Central Composite design. Apart from the optimisation methodologies, the listed designs are not flexible enough in deducing properties of parameters in terms of class variables. Machine learning algorithms have unique visualisations for the dataset presented with appropriate learning algorithms. The classification algorithms cannot be applied on all datasets and selection of classifier is essential in this regard. To resolve this issue, factor-response relationship needs to be evaluated as dataset and subsequent preprocessing could lead to appropriate results. The aim of the current study was to investigate the data-mining accuracy on the dataset developed using in-vitro pyruvate production using organic sources for the first time. The attributes were subjected to comparative classification on various classifiers and based on accuracy, multilayer perceptron (neural network algorithm) was selected as classifier. As per the results, the model showed significant results for prediction of classes and a good fit. The learning curve developed also showed the datasets converging and were linearly separable.


Asunto(s)
Carbono , Fermentación , Carbono/metabolismo , Aprendizaje Automático , Algoritmos , Ácido Pirúvico/metabolismo , Redes Neurales de la Computación , Minería de Datos/métodos
3.
Yale J Biol Med ; 97(2): 153-164, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38947101

RESUMEN

The blood-brain barrier (BBB) prevents the use of many drugs for the treatment of neurological disorders. Recently, nitrogen-doped carbon dots (NCDs) have emerged as promising nanocarriers to cross BBB. The primary focus of our study was to evaluate the effectiveness of NCDs for the symptomatic treatment of Alzheimer's disease (AD). In this study, we developed and characterized NCDs bound to rutin, a flavonoid with known benefits for AD. Despite its benefits, the transportation of rutin via NCDs for AD therapy has not been explored previously. We characterized the particles using FTIR and UV-visible spectroscopy followed by atomic force microscopy. Once the design was optimized and validated, we performed in vivo testing via a hemolytic assay to optimize the dosage. Preliminary in vitro testing was performed in AlCl3-induced rat models of AD whereby a single dose of 10 mg/kg NCDs-rutin was administered intraperitoneally. Interestingly, this single dose of 10 mg/kg NCDs-rutin produced the same behavioral effects as 50 mg/kg rutin administered intraperitoneally for 1 month. Similarly, histological and biomarker profiles (SOD2 and TLR4) also presented significant protective effects of NCDs-rutin against neuronal loss, inflammation, and oxidative stress. Hence, NCDs-rutin are a promising approach for the treatment of neurological diseases.


Asunto(s)
Enfermedad de Alzheimer , Carbono , Glucosa , Nitrógeno , Rutina , Rutina/farmacología , Rutina/química , Animales , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/metabolismo , Carbono/química , Carbono/farmacología , Nitrógeno/química , Ratas , Glucosa/metabolismo , Masculino , Puntos Cuánticos/química , Modelos Animales de Enfermedad , Estrés Oxidativo/efectos de los fármacos , Humanos
4.
Radiat Oncol ; 19(1): 85, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38956684

RESUMEN

BACKGROUND: Radiotherapy is essential in the treatment of prostate cancer. An alternative to conventional photon radiotherapy is the application of carbon ions, which provide a superior intratumoral dose distribution and less induced damage to adjacent healthy tissue. A common characteristic of prostate cancer cells is their dependence on androgens which is exploited therapeutically by androgen deprivation therapy in the advanced prostate cancer stage. Here, we aimed to analyze the transcriptomic response of prostate cancer cells to irradiation by photons in comparison to carbon ions, focusing on DNA damage, DNA repair and androgen receptor signaling. METHODS: Prostate cancer cell lines LNCaP (functional TP53 and androgen receptor signaling) and DU145 (dysfunctional TP53 and androgen receptor signaling) were irradiated by photons or carbon ions and the subsequent DNA damage was assessed by immuno-cytofluorescence. Furthermore, the cells were treated with an androgen-receptor agonist. The effects of irradiation and androgen treatment on the gene regulation and the transcriptome were investigated by RT-qPCR and RNA sequencing, followed by bioinformatic analysis. RESULTS: Following photon or carbon ion irradiation, both LNCaP and DU145 cells showed a dose-dependent amount of visible DNA damage that decreased over time, indicating occurring DNA repair. In terms of gene regulation, mRNAs involved in the TP53-dependent DNA damage response were significantly upregulated by photons and carbon ions in LNCaP but not in DU145 cells, which generally showed low levels of gene regulation after irradiation. Both LNCaP and DU145 cells responded to photons and carbon ions by downregulation of genes involved in DNA repair and cell cycle, partially resembling the transcriptome response to the applied androgen receptor agonist. Neither photons nor carbon ions significantly affected canonical androgen receptor-dependent gene regulation. Furthermore, certain genes that were specifically regulated by either photon or carbon ion irradiation were identified. CONCLUSION: Photon and carbon ion irradiation showed a significant congruence in terms of induced signaling pathways and transcriptomic responses. These responses were strongly impacted by the TP53 status. Nevertheless, irradiation mode-dependent distinct gene regulations with undefined implication for radiotherapy outcome were revealed. Androgen receptor signaling and irradiations shared regulation of certain genes with respect to DNA-repair and cell-cycle.


Asunto(s)
Fotones , Neoplasias de la Próstata , Receptores Androgénicos , Transducción de Señal , Transcriptoma , Proteína p53 Supresora de Tumor , Humanos , Masculino , Neoplasias de la Próstata/radioterapia , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Receptores Androgénicos/metabolismo , Receptores Androgénicos/genética , Proteína p53 Supresora de Tumor/metabolismo , Transcriptoma/efectos de la radiación , Transducción de Señal/efectos de la radiación , Daño del ADN/efectos de la radiación , Radioterapia de Iones Pesados , Reparación del ADN , Regulación Neoplásica de la Expresión Génica/efectos de la radiación , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Línea Celular Tumoral , Carbono/farmacología
5.
PLoS One ; 19(7): e0303808, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38959277

RESUMEN

Calcium Hydroxide-based endodontic sealer loaded with antimicrobial agents have been commonly employed in conventional root canal treatment. These sealers are not effective against E. faecalis due to the persistent nature of this bacterium and its ability to evade the antibacterial action of calcium hydroxide. Therefore, endodontic sealer containing Carbon nanodots stabilized silver nanoparticles (CD-AgNPs) was proposed to combat E. faecalis. The therapeutic effect of CD-AgNPs was investigated and a new cytocompatible Calcium Hydroxide-based endodontic sealer enriched with CD-AgNPs was synthesized that exhibited a steady release of Ag+ ions and lower water solubility at 24 hours, and enhanced antibacterial potential against E. faecalis. CD-AgNPs was synthesized and characterized morphologically and compositionally by Scanning Electron Microscopy, Fourier Transform Infrared Spectroscopy (FTIR), and UV-Vis Spectroscopy, followed by optimization via minimum inhibitory concentration (MIC) determination against E. faecalis by broth microdilution technique and Cytotoxicity analysis against NIH3T3 cell lines via Alamar Blue assay. Calcium hydroxide in distilled water was taken as control (C), Calcium hydroxide with to CD-AgNPs (5mg/ml and 10mg/ml) yielded novel endodontic sealers (E1 and E2). Morphological and chemical analysis of the novel sealers were done by SEM and FTIR; followed by in vitro assessment for antibacterial potential against E. faecalis via agar disc diffusion method, release of Ag+ ions for 21 days by Atomic Absorption Spectrophotometry and water solubility by weight change for 21 days. CD-AgNPs were 15-20 nm spherical-shaped particles in uniformly distributed clusters and revealed presence of constituent elements in nano-assembly. FTIR spectra revealed absorption peaks that correspond to various functional groups. UV-Vis absorption spectra showed prominent peaks that correspond to Carbon nanodots and Silver nanoparticles. CD-AgNPs exhibited MIC value of 5mg/ml and cytocompatibility of 84.47% with NIH3T3 cell lines. Novel endodontic sealer cut-discs revealed irregular, hexagonal particles (100-120 nm) with aggregation and rough structure with the presence of constituent elements. FTIR spectra of novel endodontic sealers revealed absorption peaks that correspond to various functional groups. Novel endodontic sealers exhibited enhanced antibacterial potential where E-2 showed greatest inhibition zone against E. faecalis (6.3±2 mm), a steady but highest release of Ag+ ions was exhibited by E-1 (0.043±0.0001 mg/mL) and showed water solubility of <3% at 24 hours where E-2 showed minimal weight loss at all time intervals. Novel endodontic sealers were cytocompatible and showed enhanced antibacterial potential against E. faecalis, however, E2 outperformed in this study in all aspects.


Asunto(s)
Antibacterianos , Hidróxido de Calcio , Carbono , Enterococcus faecalis , Nanopartículas del Metal , Pruebas de Sensibilidad Microbiana , Materiales de Obturación del Conducto Radicular , Plata , Plata/química , Plata/farmacología , Hidróxido de Calcio/química , Hidróxido de Calcio/farmacología , Animales , Ratones , Nanopartículas del Metal/química , Materiales de Obturación del Conducto Radicular/química , Materiales de Obturación del Conducto Radicular/farmacología , Enterococcus faecalis/efectos de los fármacos , Enterococcus faecalis/crecimiento & desarrollo , Células 3T3 NIH , Antibacterianos/farmacología , Antibacterianos/química , Carbono/química , Espectroscopía Infrarroja por Transformada de Fourier
6.
Sci Adv ; 10(27): eadl5822, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38959317

RESUMEN

The importance of phosphorus (P) in regulating ecosystem responses to climate change has fostered P-cycle implementation in land surface models, but their CO2 effects predictions have not been evaluated against measurements. Here, we perform a data-driven model evaluation where simulations of eight widely used P-enabled models were confronted with observations from a long-term free-air CO2 enrichment experiment in a mature, P-limited Eucalyptus forest. We show that most models predicted the correct sign and magnitude of the CO2 effect on ecosystem carbon (C) sequestration, but they generally overestimated the effects on plant C uptake and growth. We identify leaf-to-canopy scaling of photosynthesis, plant tissue stoichiometry, plant belowground C allocation, and the subsequent consequences for plant-microbial interaction as key areas in which models of ecosystem C-P interaction can be improved. Together, this data-model intercomparison reveals data-driven insights into the performance and functionality of P-enabled models and adds to the existing evidence that the global CO2-driven carbon sink is overestimated by models.


Asunto(s)
Ciclo del Carbono , Dióxido de Carbono , Eucalyptus , Bosques , Fósforo , Eucalyptus/metabolismo , Dióxido de Carbono/metabolismo , Fósforo/metabolismo , Fotosíntesis , Cambio Climático , Ecosistema , Carbono/metabolismo , Modelos Teóricos , Secuestro de Carbono
7.
Nanotheranostics ; 8(4): 442-457, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38961886

RESUMEN

The global incidence of cancer continues to rise, posing a significant public health concern. Although numerous cancer therapies exist, each has limitations and complications. The present study explores alternative cancer treatment approaches, combining hyperthermia and photodynamic therapy (PDT). Magnetic nanoparticles (MNPs) and amine-functionalized carbon quantum dots (A-CQDs) were synthesized separately and then covalently conjugated to form a single nanosystem for combinational therapy (M-CQDs). The successful conjugation was confirmed using zeta potential, Fourier transform infrared spectroscopy (FT-IR), and UV-visible spectroscopy. Morphological examination in transmission electron microscopy (TEM) further verified the conjugation of CQDs with MNPs. Energy dispersive X-ray spectroscopy (EDX) revealed that M-CQDs contain approximately 12 weight percentages of carbon. Hyperthermia studies showed that both MNP and M-CQDs maintain a constant therapeutic temperature at lower frequencies (260.84 kHz) with high specific absorption rates (SAR) of 118.11 and 95.04 W/g, respectively. In vitro studies demonstrated that MNPs, A-CQDs, and M-CQDs are non-toxic, and combinational therapy (PDT + hyperthermia) resulted in significantly lower cell viability (~4%) compared to individual therapies. Similar results were obtained with Hoechst and propidium iodide (PI) staining assays. Hence, the combination therapy of PDT and hyperthermia shows promise as a potential alternative to conventional therapies, and it could be further explored in combination with existing conventional treatments.


Asunto(s)
Carbono , Hipertermia Inducida , Nanopartículas de Magnetita , Neoplasias , Fotoquimioterapia , Puntos Cuánticos , Puntos Cuánticos/química , Fotoquimioterapia/métodos , Humanos , Carbono/química , Hipertermia Inducida/métodos , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/uso terapéutico , Neoplasias/terapia , Neoplasias/tratamiento farmacológico , Supervivencia Celular/efectos de los fármacos , Línea Celular Tumoral , Terapia Combinada , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/farmacología
8.
Microbiome ; 12(1): 121, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38970122

RESUMEN

BACKGROUND: Despite rapid advances in genomic-resolved metagenomics and remarkable explosion of metagenome-assembled genomes (MAGs), the function of uncultivated anaerobic lineages and their interactions in carbon mineralization remain largely uncertain, which has profound implications in biotechnology and biogeochemistry. RESULTS: In this study, we combined long-read sequencing and metatranscriptomics-guided metabolic reconstruction to provide a genome-wide perspective of carbon mineralization flow from polymers to methane in an anaerobic bioreactor. Our results showed that incorporating long reads resulted in a substantial improvement in the quality of metagenomic assemblies, enabling the effective recovery of 132 high-quality genomes meeting stringent criteria of minimum information about a metagenome-assembled genome (MIMAG). In addition, hybrid assembly obtained 51% more prokaryotic genes in comparison to the short-read-only assembly. Metatranscriptomics-guided metabolic reconstruction unveiled the remarkable metabolic flexibility of several novel Bacteroidales-affiliated bacteria and populations from Mesotoga sp. in scavenging amino acids and sugars. In addition to recovering two circular genomes of previously known but fragmented syntrophic bacteria, two newly identified bacteria within Syntrophales were found to be highly engaged in fatty acid oxidation through syntrophic relationships with dominant methanogens Methanoregulaceae bin.74 and Methanothrix sp. bin.206. The activity of bin.206 preferring acetate as substrate exceeded that of bin.74 with increasing loading, reinforcing the substrate determinantal role. CONCLUSION: Overall, our study uncovered some key active anaerobic lineages and their metabolic functions in this complex anaerobic ecosystem, offering a framework for understanding carbon transformations in anaerobic digestion. These findings advance the understanding of metabolic activities and trophic interactions between anaerobic guilds, providing foundational insights into carbon flux within both engineered and natural ecosystems. Video Abstract.


Asunto(s)
Carbono , Metagenómica , Metano , Metano/metabolismo , Carbono/metabolismo , Metagenómica/métodos , Reactores Biológicos/microbiología , Metagenoma , Bacterias/genética , Bacterias/metabolismo , Bacterias/clasificación , Filogenia , Anaerobiosis , Transcriptoma , Genoma Bacteriano , Microbiota , Perfilación de la Expresión Génica
9.
Microbiome ; 12(1): 123, 2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-38971798

RESUMEN

BACKGROUND: The Atribacterota are widely distributed in the subsurface biosphere. Recently, the first Atribacterota isolate was described and the number of Atribacterota genome sequences retrieved from environmental samples has increased significantly; however, their diversity, physiology, ecology, and evolution remain poorly understood. RESULTS: We report the isolation of the second member of Atribacterota, Thermatribacter velox gen. nov., sp. nov., within a new family Thermatribacteraceae fam. nov., and the short-term laboratory cultivation of a member of the JS1 lineage, Phoenicimicrobium oleiphilum HX-OS.bin.34TS, both from a terrestrial oil reservoir. Physiological and metatranscriptomics analyses showed that Thermatribacter velox B11T and Phoenicimicrobium oleiphilum HX-OS.bin.34TS ferment sugars and n-alkanes, respectively, producing H2, CO2, and acetate as common products. Comparative genomics showed that all members of the Atribacterota lack a complete Wood-Ljungdahl Pathway (WLP), but that the Reductive Glycine Pathway (RGP) is widespread, indicating that the RGP, rather than WLP, is a central hub in Atribacterota metabolism. Ancestral character state reconstructions and phylogenetic analyses showed that key genes encoding the RGP (fdhA, fhs, folD, glyA, gcvT, gcvPAB, pdhD) and other central functions were gained independently in the two classes, Atribacteria (OP9) and Phoenicimicrobiia (JS1), after which they were inherited vertically; these genes included fumarate-adding enzymes (faeA; Phoenicimicrobiia only), the CODH/ACS complex (acsABCDE), and diverse hydrogenases (NiFe group 3b, 4b and FeFe group A3, C). Finally, we present genome-resolved community metabolic models showing the central roles of Atribacteria (OP9) and Phoenicimicrobiia (JS1) in acetate- and hydrocarbon-rich environments. CONCLUSION: Our findings expand the knowledge of the diversity, physiology, ecology, and evolution of the phylum Atribacterota. This study is a starting point for promoting more incisive studies of their syntrophic biology and may guide the rational design of strategies to cultivate them in the laboratory. Video Abstract.


Asunto(s)
Carbono , Yacimiento de Petróleo y Gas , Filogenia , Carbono/metabolismo , Yacimiento de Petróleo y Gas/microbiología , ARN Ribosómico 16S/genética , Genoma Bacteriano , Alcanos/metabolismo
10.
Glob Chang Biol ; 30(7): e17405, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38973563

RESUMEN

Anthropogenic activities have raised nitrogen (N) input worldwide with profound implications for soil carbon (C) cycling in ecosystems. The specific impacts of N input on soil organic matter (SOM) pools differing in microbial availability remain debatable. For the first time, we used a much-improved approach by effectively combining the 13C natural abundance in SOM with 21 years of C3-C4 vegetation conversion and long-term incubation. This allows to distinguish the impact of N input on SOM pools with various turnover times. We found that N input reduced the mineralization of all SOM pools, with labile pools having greater sensitivity to N than stable ones. The suppression in SOM mineralization was notably higher in the very labile pool (18%-52%) than the labile and stable (11%-47%) and the very stable pool (3%-21%) compared to that in the unfertilized control soil. The very labile C pool made a strong contribution (up to 60%) to total CO2 release and also contributed to 74%-96% of suppressed CO2 with N input. This suppression of SOM mineralization by N was initially attributed to the decreased microbial biomass and soil functions. Over the long-term, the shift in bacterial community toward Proteobacteria and reduction in functional genes for labile C degradation were the primary drivers. In conclusion, the higher the availability of the SOM pools, the stronger the suppression of their mineralization by N input. Labile SOM pools are highly sensitive to N availability and may hold a greater potential for C sequestration under N input at global scale.


Asunto(s)
Carbono , Nitrógeno , Microbiología del Suelo , Suelo , Suelo/química , Nitrógeno/metabolismo , Nitrógeno/análisis , Carbono/metabolismo , Carbono/análisis , Ciclo del Carbono , Dióxido de Carbono/análisis , Dióxido de Carbono/metabolismo , Isótopos de Carbono/análisis , Biomasa
11.
Sci Adv ; 10(27): eadk5430, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38968357

RESUMEN

Mangroves' ability to store carbon (C) has long been recognized, but little is known about whether planted mangroves can store C as efficiently as naturally established (i.e., intact) stands and in which time frame. Through Bayesian logistic models compiled from 40 years of data and built from 684 planted mangrove stands worldwide, we found that biomass C stock culminated at 71 to 73% to that of intact stands ~20 years after planting. Furthermore, prioritizing mixed-species planting including Rhizophora spp. would maximize C accumulation within the biomass compared to monospecific planting. Despite a 25% increase in the first 5 years following planting, no notable change was observed in the soil C stocks thereafter, which remains at a constant value of 75% to that of intact soil C stock, suggesting that planting effectively prevents further C losses due to land use change. These results have strong implications for mangrove restoration planning and serve as a baseline for future C buildup assessments.


Asunto(s)
Biomasa , Carbono , Suelo , Humedales , Carbono/metabolismo , Suelo/química , Rhizophoraceae/crecimiento & desarrollo , Rhizophoraceae/metabolismo , Teorema de Bayes , Ecosistema
12.
Environ Monit Assess ; 196(8): 695, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38963430

RESUMEN

When ecology thrives, civilization thrives, and when ecology declines, civilization declines. Based on panel data from 30 provinces in China from 2000 to 2021, this study used marginal abatement costs to estimate the co-benefits of pollution reduction and carbon reduction. Two-way fixed effect and two-stage intermediary effect models were used to evaluate the impact of digital technology on co-benefits and its indirect channels. The results indicated that China's total carbon emissions maintained a steady growth trend, while air pollution showed a fluctuating declining trend. Reaching peak carbon neutrality calls for more innovative solutions. Under joint emission reduction efforts, the study revealed marginal abatement cost savings of 535.8 million yuan/million tons and 6216.5 million yuan/µg/m3 for carbon reduction and pollution reduction, respectively. Most importantly, the study confirmed that joint emission reduction programs can reduce environmental governance costs more than individual emission reductions can, and the co-benefits increased from 37.983 to 44.757. The co-benefits generally showed a trend of fluctuation and increases and had the characteristics of phased transformation. Intragroup differences and cross-overlapping between regions made regional differences in co-benefits obvious. The subversive, permeable, and integrated features of digital technology have resulted in the all-around transformation of the economy and society, and the new technology-economy paradigm has significantly improved co-benefits. The conclusion remains valid after robustness testing and controlling for endogeneity problems. The results of the mechanism analysis suggest that digital technology can indirectly improve synergies through the intermediary channels of fostering green technology innovation, reducing energy consumption intensity and improving the energy structure.


Asunto(s)
Contaminación del Aire , Tecnología Digital , Monitoreo del Ambiente , Contaminación del Aire/prevención & control , Contaminación del Aire/estadística & datos numéricos , China , Monitoreo del Ambiente/métodos , Carbono/análisis , Contaminantes Atmosféricos/análisis
13.
Sci Adv ; 10(27): eadn7896, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38968361

RESUMEN

Recent years have witnessed a surge of interest in tuning the optical properties of organic semiconductors for diverse applications. However, achieving control over the optical bandgap in the second near-infrared (NIR-II) window has remained a major challenge. To address this, here we report a polaron engineering strategy that introduces diverse defects into carbon quantum dots (CQDs). These defects induce lattice distortions resulting in the formation of polarons, which can absorb the near-field scattered light. Furthermore, the formed polarons in N-related vacancies can generate thermal energy through the coupling of lattice vibrations, while the portion associated with O-related defects can return to the ground state in the form of NIR-II fluorescence. On the basis of this optical absorption model, these CQDs have been successfully applied to NIR-II fluorescence imaging and photothermal therapy. This discovery could open a promising route for the polarons of organic semiconductor materials as NIR-II absorbers in nanomedical applications.


Asunto(s)
Carbono , Rayos Infrarrojos , Neoplasias , Puntos Cuánticos , Puntos Cuánticos/química , Carbono/química , Humanos , Neoplasias/terapia , Neoplasias/diagnóstico por imagen , Animales , Imagen Óptica/métodos , Ratones , Línea Celular Tumoral
14.
Mikrochim Acta ; 191(7): 436, 2024 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-38954059

RESUMEN

A fluorescence probe based on molecularly imprinted polymers on red emissive biomass-derived carbon dots (r-BCDs@MIPs) was developed to detect tyramine in fermented meat products. The red emissive biomass-derived carbon dots (r-BCDs) were synthesized by the one-step solvothermal method using discarded passion fruit shells as raw materials. The fluorescence emission peak of r-BCDs was at 670 nm, and the relative quantum yield (QY) was about 2.44%. Molecularly imprinted sensing materials were prepared with r-BCDs as fluorescent centers for the detection of trace tyramine, which showed a good linear response in the concentration range of tyramine from 1 to 40 µg L-1. The linear correlation coefficient was 0.9837, and the limit of detection was 0.77 µg L-1. The method was successfully applied to the determination of tyramine in fermented meat products, and the recovery was 87.17-106.02%. The reliability of the results was verified through high-performance liquid chromatography (HPLC). Furthermore, we combined the r-BCDs@MIPs with smartphone-assisted signal readout to achieve real-time detection of tyramine in real samples. Considering its simplicity and convenience, the method could be used as a rapid and low-cost promising platform with broad application prospects for on-site detection of trace tyramine with smartphone-assisted signal readout.


Asunto(s)
Carbono , Colorantes Fluorescentes , Límite de Detección , Productos de la Carne , Polímeros Impresos Molecularmente , Puntos Cuánticos , Teléfono Inteligente , Tiramina , Tiramina/análisis , Tiramina/química , Carbono/química , Puntos Cuánticos/química , Productos de la Carne/análisis , Colorantes Fluorescentes/química , Polímeros Impresos Molecularmente/química , Espectrometría de Fluorescencia/métodos , Biomasa , Fermentación
15.
Appl Microbiol Biotechnol ; 108(1): 408, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38967685

RESUMEN

The simulations and predictions obtained from mathematical models of bioprocesses conducted by microorganisms are not overvalued. Mechanistic models are bringing a better process understanding and the possibility of simulating unmeasurable variables. The Dynamic Energy Budget (DEB) model is an energy balance that can be formulated for any living organism and can be classified as a structured model. In this study, the DEB model was used to describe E. coli growth in a batch reactor in carbon and nitrogen substrate limitation conditions. The DEB model provides a possibility to follow the changes in the microbes' cells including their elemental composition and content of some important cell ingredients in different growth phases in substrate limitation conditions which makes it more informative compared to Monod's model. The model can be used as an optimal choice between Monod-like models and flux-based approaches. KEY POINTS: • The DEB model can be used to catch changes in elemental composition of E. coli • Bacteria batch culture growth phases can be explained by the DEB model • The DEB model is more informative compared to Monod's based models.


Asunto(s)
Reactores Biológicos , Carbono , Metabolismo Energético , Escherichia coli , Nitrógeno , Escherichia coli/crecimiento & desarrollo , Escherichia coli/metabolismo , Nitrógeno/metabolismo , Carbono/metabolismo , Reactores Biológicos/microbiología , Modelos Biológicos , Medios de Cultivo/química , Técnicas de Cultivo Celular por Lotes , Modelos Teóricos
16.
Waste Manag Res ; 42(7): 509-510, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38946251
17.
Glob Chang Biol ; 30(7): e17391, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38946293

RESUMEN

Heat released from soil organic carbon (SOC) decomposition (referred to as microbial heat hereafter) could alter the soil's thermal and hydrological conditions, subsequently modulate SOC decomposition and its feedback with climate. While understanding this feedback is crucial for shaping policy to achieve specific climate goal, it has not been comprehensively assessed. This study employs the ORCHIDEE-MICT model to investigate the effects of microbial heat, referred to as heating effect, focusing on their impacts on SOC accumulation, soil temperature and net primary productivity (NPP), as well as implication on land-climate feedback under two CO2 emissions scenarios (RCP2.6 and RCP8.5). The findings reveal that the microbial heat decreases soil carbon stock, predominantly in upper layers, and elevates soil temperatures, especially in deeper layers. This results in a marginal reduction in global SOC stocks due to accelerated SOC decomposition. Altered seasonal cycles of SOC decomposition and soil temperature are simulated, with the most significant temperature increase per unit of microbial heat (0.31 K J-1) occurring at around 273.15 K (median value of all grid cells where air temperature is around 273.15 K). The heating effect leads to the earlier loss of permafrost area under RCP8.5 and hinders its restoration under RCP2.6 after peak warming. Although elevated soil temperature under climate warming aligns with expectation, the anticipated accelerated SOC decomposition and large amplifying feedback on climate warming were not observed, mainly because of reduced modeled initial SOC stock and limited NPP with heating effect. These underscores the multifaceted impacts of microbial heat. Comprehensive understanding of these effects would be vital for devising effective climate change mitigation strategies in a warming world.


Asunto(s)
Carbono , Cambio Climático , Calor , Suelo , Suelo/química , Carbono/análisis , Microbiología del Suelo , Modelos Teóricos , Estaciones del Año
18.
Glob Chang Biol ; 30(7): e17404, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38967125

RESUMEN

The fraction of net primary productivity (NPP) allocated to belowground organs (fBNPP) in grasslands is a critical parameter in global carbon cycle models; moreover, understanding the effect of precipitation changes on this parameter is vital to accurately estimating carbon sequestration in grassland ecosystems. However, how fBNPP responds to temporal precipitation changes along a gradient from extreme drought to extreme wetness, remains unclear, mainly due to the lack of long-term data of belowground net primary productivity (BNPP) and the fact that most precipitation experiments did not have a gradient from extreme drought to extreme wetness. Here, by conducting both a precipitation gradient experiment (100-500 mm) and a long-term observational study (34 years) in the Inner Mongolia grassland, we showed that fBNPP decreased linearly along the precipitation gradient from extreme drought to extreme wetness due to stronger responses in aboveground NPP to drought and wet conditions than those of BNPP. Our further meta-analysis in grasslands worldwide also indicated that fBNPP increased when precipitation decreased, and the vice versa. Such a consistent pattern of fBNPP response suggests that plants increase the belowground allocation with decreasing precipitation, while increase the aboveground allocation with increasing precipitation. Thus, the linearly decreasing response pattern in fBNPP should be incorporated into models that forecast carbon sequestration in grassland ecosystems; failure to do so will lead to underestimation of the carbon stock in drought years and overestimation of the carbon stock in wet years in grasslands.


Asunto(s)
Carbono , Sequías , Pradera , Lluvia , Carbono/análisis , Carbono/metabolismo , China , Ciclo del Carbono , Secuestro de Carbono
19.
Sci Rep ; 14(1): 15114, 2024 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-38956155

RESUMEN

Wheat straw returning is a common agronomic measure in the farmland. Understanding organic carbon transformation is of great significance for carbon budget under the premise of widespread distribution of cadmium (Cd) contaminated soils. An incubation experiment was conducted to assess the influence of Cd contamination on the decomposition and accumulation of total organic carbon (TOC) as well as the composition and abundance of bacterial communities in eight soil types with wheat straw addition. The results showed that inhibition of Cd contamination on microbially mediated organic carbon decomposition was affected by soil types. The lower cumulative C mineralization and higher TOC content could be observed in the acidic soils relative to that in the alkaline soils. The content of Cd in soil exhibits different effects on the inhibition in decomposition of TOC. The high dosage level of Cd had stronger inhibitory impact due to its high toxicity. The decomposition of TOC was restricted by a reduction in soil bacterial abundance and weakening of bacterial activities. Redundancy analysis (RDA) indicated that Proteobacteria and Gemmatimonadetes were abundant in alkaline Cd-contaminated soils with wheat straw addition, while Bacteroidetes dominated cumulative C mineralization in acidic Cd-contamination soils. Moreover, the abundance of predicted functional bacteria indicated that high-dose Cd-contamination and acid environment all inhibited the decomposition of TOC. The present study suggested that pH played an important role on carbon dynamics in the Cd-contaminated soils with wheat straw addition.


Asunto(s)
Cadmio , Carbono , Microbiología del Suelo , Contaminantes del Suelo , Suelo , Triticum , Cadmio/metabolismo , Cadmio/análisis , Triticum/metabolismo , Triticum/química , Contaminantes del Suelo/análisis , Contaminantes del Suelo/metabolismo , Carbono/metabolismo , Carbono/análisis , Suelo/química , Bacterias/metabolismo , Biodegradación Ambiental , Concentración de Iones de Hidrógeno
20.
Glob Chang Biol ; 30(7): e17413, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38982678

RESUMEN

Tasmanian eucalypt forests are among the most carbon-dense in the world, but projected climate change could destabilize this critical carbon sink. While the impact of abiotic factors on forest ecosystem carbon dynamics have received considerable attention, biotic factors such as the input of animal scat are less understood. Tasmanian devils (Sarcophilus harrisii)-an osteophageous scavenger that can ingest and solubilize nutrients locked in bone material-may subsidize plant and microbial productivity by concentrating bioavailable nutrients (e.g., nitrogen and phosphorus) in scat latrines. However, dramatic declines in devil population densities, driven by the spread of a transmissible cancer, may have underappreciated consequences for soil organic carbon (SOC) storage and forest productivity by altering nutrient cycling. Here, we fuse experimental data and modeling to quantify and predict future changes to forest productivity and SOC under various climate and scat-quality futures. We find that devil scat significantly increases concentrations of nitrogen, ammonium, phosphorus, and phosphate in the soil and shifts soil microbial communities toward those dominated by r-selected (e.g., fast-growing) phyla. Further, under expected increases in temperature and changes in precipitation, devil scat inputs are projected to increase above- and below-ground net primary productivity and microbial biomass carbon through 2100. In contrast, when devil scat is replaced by lower-quality scat (e.g., from non-osteophageous scavengers and herbivores), forest carbon pools are likely to increase more slowly, or in some cases, decline. Together, our results suggest often overlooked biotic factors will interact with climate change to drive current and future carbon pool dynamics in Tasmanian forests.


Asunto(s)
Cambio Climático , Bosques , Marsupiales , Suelo , Animales , Marsupiales/fisiología , Suelo/química , Tasmania , Microbiología del Suelo , Ecosistema , Nitrógeno/metabolismo , Nitrógeno/análisis , Fósforo/análisis , Fósforo/metabolismo , Carbono/metabolismo , Carbono/análisis , Dinámica Poblacional
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