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1.
Carbohydr Res ; 545: 109284, 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39357145

RESUMO

Several lactic acid bacteria are capable of producing water-soluble exopolysaccharides such as dextran from sucrose by using glucansucrases. Several recombinant glucansucrases were described, however, yields were often limited and most dextrans were branched at position O3. In this study, the dextransucrase from Ligilactobacillus animalis TMW 1.971 was recombinantly produced without its N-terminal variable region and used for dextran synthesis. The enzyme expressed well and showed very high total as well as transferase activities compared to other glucansucrases. It was able to transfer nearly all glucose from sucrose to oligo- and polymeric products under certain conditions (about 95 % of glucose transferred). The high efficiency of the enzyme made it possible to obtain absolute dextran yields of up to 214.9 g/L from a 1.5 M sucrose solution. Structural characterization of the products showed that the dextrans produced have a rather low molecular weight, a narrow size distribution, and are completely linear. Furthermore, we showed that various low molecular weight dextrans or 1,6-linked isomalto-oligosaccharides can be efficiently produced by acid hydrolysis. Overall, we demonstrated that Ligilactobacillus animalis TMW 1.971 dextransucrase can be used to efficiently synthesize dextrans with a quite unique structural composition. The dextrans produced have a high potential for further applications such as synthesis of copolymers or size standards with a very defined molecular structure.

2.
Front Public Health ; 12: 1447663, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39360248

RESUMO

Soil provides multiple and diverse functions (e.g., the provision of food and the regulation of carbon), which underpin the health of animals, humans, the environment and the planet. However, the world's soils face existential challenges. To this end, the concept of Soil Security was developed, compelled to: "maintain and improve soils worldwide so that they can continue to provide food, fiber and fresh water, contribute to energy and climate sustainability and help to maintain biodiversity and the overall protection of ecosystem goods and services." In parallel, the concept of One Health likewise works across the human-animal-environment interface, highly relevant for the goals of Soil Security. In this review, we evaluated the roles which both the Soil Security and One Health concepts have served in the literature between 2012 and 2023 and explore the potential linkages between both concepts. We outline that both concepts are used in disparate fields, despite considerable overlap in aims and objectives. We highlight the Soil Health concept as a potential connector between Soil Security and One Health. Overall, we argue that both Soil Security and One Health are highly complementary fields of scientific inquiry with solid leverage for translation into policy and practice. However, there is a need to define One Health dimensions, as has been done for Soil Security. As such, we proffer five measurable dimensions for One Health, the "5Cs"-Capacity, Condition, Capital, Connectivity and Codification-to allow for an overall measure of One Health. Finally, we advocate for a biosphere-focused framework to collectively make progress toward the 2030 Sustainable Development Goals and other global existential challenges.


Assuntos
Saúde Única , Solo , Desenvolvimento Sustentável , Humanos , Ecossistema , Conservação dos Recursos Naturais , Animais , Objetivos
3.
Artigo em Inglês | MEDLINE | ID: mdl-39388345

RESUMO

The occurrence of adhesive failure under impact poses significant risks, including property damage, structural collapse, and even loss of life. Herein, we have developed a series of impact-resistant adhesives by incorporating dynamic B-O linkages into linear polymeric chains. These adhesives not only possess broad-area adhesion and superior adhesive strength compared to 3 M commercial products but also exhibit a shear-stiffening effect. The shear-stiffening effect provided by the B-O linkages endows the adhesives with remarkable impact resistance, achieving a force attenuation efficiency of 84.3-86.3%. Additionally, when they are bonded to target materials, the resulting sandwich structures retain their excellent impact resistance. Therefore, this class of impact-resistant adhesives with a shear-stiffening effect shows significant potential for applications in protecting precision instruments and buildings.

4.
Int J Biol Macromol ; : 136471, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39393736

RESUMO

Monosaccharide composition and glycosidic linkages analysis are essential for the structural characterization and biological activity research of polysaccharides. To simplify the analysis steps and improve detection efficiency, this study developed monosaccharide compositions and glycosidic linkages detection methods based on UPLC-QqQ-MS/MS, and established a plant polysaccharide glycosidic linkages library. Furthermore, the detailed analysis process of monosaccharide compositions and glycosidic linkages was presented through a plant polysaccharide (Chinese bayberry wine polysaccharide, CPW) example. The results showed that the monosaccharide analysis method could identify and quantify 20 monosaccharides within 13 min by 6 chromatograms. By this method, 7 monosaccharides were detected in CPW, which was consistent with previous results obtained using ion chromatography. Meanwhile, the UPLC-QqQ-MS/MS based method could analyze 112 glycosidic linkages of 9 plant monosaccharides within 30 min, and the results were distributed on 11 chromatograms. According to the approach, 44 different glycosidic linkages were identified in CPW. Based on Congo red assay and molecular weight as well as our findings of monosaccharide composition and glycosidic linkages, we proposed that CPW may consist of two distinct sugar chains: One composed of 1-2,4-Rha, 1-3,4-GalA, and 1-F-Ara, and the other composed of 1-3,4-Gal, 1-4-Gal, 1-3,4,6-Gal, and 1-F-Ara.

5.
Adv Sci (Weinh) ; : e2402127, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39279462

RESUMO

Multi-stable structures can be reconfigured with fewer, lightweight, and less accurate actuators. This is because the attraction domain in the multi-stable energy landscape provides both reconfiguration guidance and shape accuracy. Additionally, such structures can generate impulsive motion due to structural instability. Most multi-stable units are planar structures, while spatial linkages can generate complex 3D motion and hold a more promising potential for applications. This study proposes a generalized approach to design a type of intrinsically multi-stable spatial (IMSS) linkages with multiple prescriptible configurations, which are structurally compatible, and naturally stable at these states. It reveals that all over-constrained mechanisms can be transformed into multi-stable structures with the same design method. Single-loop bi-stable 4R and quadra-stable 6R spatial linkages modules with intrinsic non-symmetric stable states, which are transformed from fundamental kinematic linkage mechanisms unit such as Bennett and Bricard linkages, are designed to illustrate the basic idea and the superiority over the ordinary methods. Multi-loop assembly by these IMSS linkage modules shows potential for practical applications that are required for the deployability and impulsivity of reconfiguration. Two preliminary design cases of a deployable tube and an impulsive gripper are experimentally presented to validate this applicability. Further promisingly, this design method of IMSS linkages paves the way for morphing platforms with lightweight actuation, high shape accuracy, high stiffness, and prescribed impulsive 3D motion.

6.
Sci Rep ; 14(1): 21601, 2024 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-39285164

RESUMO

Dietary decisions by predators can affect prey abundance and overall food web dynamics. Many predators do not forage on the same prey at the same frequency throughout their lives. Ontogenetic shifts in prey preference are not, however, often accounted for when modeling food web relationships, despite growing literature that suggests that stage specific dietary relationships may be an important consideration when modeling trophic interactions. We investigated the importance of considering size-structure of a predator population with ontogenetic diet shifts in evaluating relationships with prey response using a manipulative experiment with the brown treesnake (Boiga irregularis) in Guam. After removing ~ 40% of the snake population via toxic mammal carrion, we measured the strength of the relationship between snake density and the response of two types of prey (lizards and mammals). We evaluated these relationships based on total population size or division of the population into stage specific size categories based on diet preference predictions. We hypothesized that the density of juvenile snakes would correlate more strongly with lizard detections, while adult snakes would better correlate to rodent detections. We also measured reproductive output following changes in rates of prey detection. As expected by known ontogenetic shifts in dietary preference, explicit stage-based models better predicted shifts in rates of observed prey items than did total predator density for both lizards and mammals. Additionally, rodent detections were predictive of one reproductive pulse from snakes, while lizard detections were not predictive or correlated. Our findings support that consideration of predatory species stage-based dietary preference can be meaningful for understanding food web dynamics, particularly when a predator has a broad diet or one that changes through time.


Assuntos
Cadeia Alimentar , Lagartos , Comportamento Predatório , Serpentes , Animais , Comportamento Predatório/fisiologia , Lagartos/fisiologia , Serpentes/fisiologia , Densidade Demográfica , Dieta , Modelos Biológicos
7.
Int J Biol Macromol ; 279(Pt 4): 135492, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39276898

RESUMO

For the first time, this study integrate the light-driven depolymerization/activation of industrial grade sodium lignosulfonate and its subsequent photo-induced radical polymerization with acrylamide (AM) and 2-acrylamido-2-methylpropanesulfonic acid (AMPS) into one-pot using MIL-100(Fe)-NH2(20) as a photocatalyst to synthesize fluid loss agent LSMP. Due to the significant hydrogen bonding effect, the agent owns excellent rheological and filtration properties. The filtrate volumes of drilling fluids containing 2.0 wt% agent before and after aging at 150 °C are only 3.6 and 4.6 mL, reducing by 85.0 % and 88.5 %, respectively, compared with pure fluids. Even at high temperatures and high salinity, LSMP still gives stunning performances with significant filtrate volumes decline of 96.58 % and 86.52 % under erosion of 25 wt% NaCl and 2.0 wt% CaCl2, separately. Meanwhile, the filtration reduction mechanism of LSMP is presented, and the probable photocatalytic mechanism is also explored: 1, under depolymerization process, the selective cleavage of ubiquitous C - O/C - C linkage bonds (ß-O-4, ß-5, α-O-4, ß-ß, 4-O-5, ß-1, dibenzodioxocin, etc.) occur, accompanied by the aromatic rings intact; 2, with the action of photo-induced carriers generated on MIL-100(Fe)-NH2(20), absorbed photons are transformed into thermal energy and the radical polymerization of green synthesis are ultimately achieved.


Assuntos
Luz , Lignina , Polimerização , Temperatura , Lignina/química , Lignina/análogos & derivados , Catálise , Processos Fotoquímicos , Biopolímeros/química , Filtração/métodos , Cloreto de Sódio/química , Salinidade
8.
Soc Sci Res ; 122: 103029, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39216908

RESUMO

Men and women's diverging fields of study choices contribute to the gender wage gap among highly educated workers in several countries, yet systematic cross-national comparisons are rare. Using data from the German Socio-Economic Panel Study, the German Microcensus, and Statistics Finland this study explores whether fields of study shape the gender wage gap differently in Germany than in Finland; two countries that display strong linkages between education and employment, but differ in the generosity of family policies. The results show that fields of study are an important source of gender wage disparities in both countries. In Germany, associations between characteristics of fields and wages do not seem to differ between the genders. In Finland, the findings suggest that women profit more than men from fields with strong linkages to occupations. Our findings highlight that research analyzing the association between fields of study and gender inequality needs to consider institutional features and gender-specific patterns.

9.
Ecol Evol ; 14(8): e11527, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39119175

RESUMO

Mites are among the most abundant invertebrates in subsurface ecosystems, and their community assemblages and distributions are often significantly influenced by the diversity of habitat resources. The cave ecosystem encompasses drastic changes in nonbiological factors, such as changes in lighting conditions from bright to extraordinarily dark and habitat gradients of surface plant resources from abundant to scarce or even disappearing, providing an ideal unique environment for evaluating the assembly mechanism of soil animal communities. Nevertheless, there still needs to be a sufficient understanding of the biodiversity patterns and drivers of mite communities across environmental gradients in karst caves. We conducted a comprehensive survey on the composition and diversity of soil mites in three photometric zones (dark, twilight, and light) of a typical karst cave and its adjoining extractive environments (forest scrub and farmland). Our research aimed to investigate the ecological relationships of mite communities between above- and below-ground habitats and the effects of abiotic factors on mite communities. We collected 49 families, 86 genera, and 1284 mites. In the external cave environment, we captured 1052 mites from 72 genera and 45 families; in the internal cave environment, we captured 232 mites from 46 genera and 29 families. The abundance, richness of genera, and diversity parameters of the mite community decreased from the cave entrance to the cave interior with decreasing light intensity. Oribatid mites dominated the mite community. Protoribates and Scheloribates were the dominant genera, along with Tectocepheus and 11 other genera, which primarily distinguished the mite communities among different habitats. Forty endemic taxa were found in the external cave environment, compared to 14 endemic taxa in the internal cave environment. The mite community showed a strong preference for the cave ecosystem habitat. Temperature, humidity, and soil nitrogen content significantly influenced the distribution pattern of mite communities (VIP > 0.8, p < 0.05).

10.
Front Plant Sci ; 15: 1430025, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39135645

RESUMO

Global climate change has markedly influenced the structure and distribution of mid-high-latitude forests. In the forest region of Northeast China, the magnitude of climate warming surpasses the global average, which presents immense challenges to the survival and habitat sustainability of dominant tree species. We predicted the potential changes in aboveground biomass, dominant tree species composition, and distribution in the forest region of Northeast China over the next century under different climatic conditions encompassing the current scenario and future scenarios (RCP2.6, RCP4.5, and RCP8.5). Forest ecosystem process model LINKAGES 3.0 was used to simulate dynamic changes in species-level aboveground biomass under four climate scenarios at the homogeneous land-type unit level. The potential spatial distribution of tree species was investigated based on three indicators: extinction, colonization, and persistence. The results showed that LINKAGES 3.0 model effectively simulated the aboveground biomass of 17 dominant tree species in the forest region of Northeast China, achieving a high accuracy with R² = 0.88. Under the current, RCP2.6, and RCP4.5 climate scenarios, the dominant tree species presented gradual increases in aboveground biomass, whereas under RCP8.5, an initial increase and subsequent decline were observed. With increasing warming magnitude, cold-temperate coniferous tree species will gradually be replaced by other temperate broad-leaved tree species. Furthermore, a large temperature increase under RCP8.5 will likely produce a significant contraction in the potential distribution range of tree species like Larch, Scotch pine, Ribbed birch, Spruce and Fir, while most temperate broad-leaved tree species and Korean pine are expected to demonstrate a northward migration. These findings provide guidance for enhancing the adaptability and resilience of forest ecosystems in middle and high latitudes and addressing the threats posed by climate warming.

11.
J Agric Food Chem ; 72(30): 17062-17071, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39036888

RESUMO

Glycoside linkage analyses of medicine and food homologous plant polysaccharides have always been a key point and a difficulty of structural characterization. The gas chromatography-mass spectrometry (GC-MS) method is one of the commonly used traditional techniques to determine glycoside linkages via partially methylated alditol acetates and aldononitrile acetates (PMAAs and PMANs). Due to the simplicity of derivatization and the highly structural asymmetry of PMANs, reverse thinking is proposed using liquid chromatography-electrospray ionization-multiple reaction monitoring mass spectrometry (LC-ESI-MRM-MS) for the first time to directly determine the neutral and acidic glycosyl linkages of polysaccharides. The complete characterization of glycoside linkages deduced from PMANs was achieved using a combination of tR values, characteristic MRM ion pairs, diagnostic ESI+-MS/MS fragmentation ions (DFIs), and optimal collision energy (OCE). The DFI and OCE parameters were confirmed to be effective for the auxiliary discrimination of some isomers of the PMANs. The practicality of LC-ESI+-MRM-MS was further verified by analyzing the glycoside linkages of polysaccharides in five medicine and food homologous plants. This method can serve as an alternative to GC-MS for the simultaneous determination of neutral and acidic glycosyl linkages in polysaccharides.


Assuntos
Glicosídeos , Polissacarídeos , Espectrometria de Massas por Ionização por Electrospray , Polissacarídeos/química , Glicosídeos/química , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão/métodos , Acetatos/química , Nitrilas/química , Metilação , Cromatografia Líquida/métodos , Extratos Vegetais/química , Cromatografia Gasosa-Espectrometria de Massas/métodos
12.
Philos Trans R Soc Lond B Biol Sci ; 379(1909): 20230165, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39034702

RESUMO

In Colombia, the long-lasting internal conflict heavily shaped the socio-ecological context and imposed relationships that persisted after the peace agreement was signed in 2016. One question of interest is whether policies or interventions conceived to attain desirable goals for the post-conflict society may be effective or, rather, if the constraints imposed by the conflict scenario might produce unintended effects, either on the environmental or the social side. To explore this issue, we envisaged the socio-ecological system as a parsimonious set of characteristic ecological and social variables within the conflict-related framework and reconstructed their interactions, exploiting elicitation-based information and the literature. We visualized the resulting interactive networks as signed digraphs. Applying the qualitative technique of loop analysis combined with numerical simulations, we predicted the response of the system to policies as drivers of change, such as subsidized credit to capital-intensive activities or policies that increase small farming competitiveness and access to markets. Highlighting causal linkages reveals that the persistence of conflict factors may produce unexpected interdependencies between licit and illicit activities and that, only in a few cases, the persistence of these mechanisms allows synergies between desirable goals.This article is part of the theme issue 'Connected interactions: enriching food web research by spatial and social interactions'.


Assuntos
Conflitos Armados , Colômbia , Humanos
13.
Environ Pollut ; 358: 124479, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38960113

RESUMO

The taxonomy of marine plastisphere communities has been extensively studied, demonstrating the ubiquity of hydrocarbonoclastic bacteria of potential biotechnological significance. However, prokaryotic functioning on plastic surfaces has received limited attention, and the question of whether these microorganisms are active and expressing specific molecular mechanisms underpinning plastisphere colonisation remains to be addressed. The aim of this study was to investigate the plastic colonisation process, to identify the active taxa involved in biofilm formation and the mechanisms used to initiate colonisation. To achieve this, a marine plastisphere characterised by active hydrocarbonoclastic genera was used as the inoculum for a short-term microcosm experiment using virgin low-density polyethylene as the sole carbon source. Following incubation for 1 and 2 weeks (representing early and late colonisation, respectively), a taxonomic and comparative metaproteomic approach revealed a significant shift in plastisphere diversity and composition, yet highlighted stability in the predominance of active Proteobacteria spanning 16 genera, including Marinomonas, Pseudomonas, and Pseudoalteromonas. Relative quantification of 1762 proteins shared between the initial plastisphere inoculum, the microcosm plastisphere and the planktonic cells in the surrounding artificial seawater, provided insights into the differential regulation of proteins associated with plastisphere formation. This included the upregulation of proteins mediating cellular attachment in the plastisphere, for example flagellin expressed by Marinomonas, Cobetia, Pseudoalteromonas, and Pseudomonas, and curli expressed by Cobetia. In addition to the differential regulation of energy metabolism in Marinomonas, Psychrobacter, Pseudomonas and Cobetia within the plastisphere relative to the surrounding seawater. Further, we identified the upregulation of amino acid metabolism and transport, including glutamine hydrolysis to glutamate in Marinomonas and unclassified Halomonadaceae, potentially coupled to ammonia availability and oxidative stress experienced within the plastisphere. Our study provides novel insights into the dynamics of plastisphere formation and function, highlighting potential targets for regulating plastisphere growth to enhance plastic bioremediation processes.


Assuntos
Biofilmes , Plâncton , Plásticos , Água do Mar , Plâncton/metabolismo , Água do Mar/microbiologia , Água do Mar/química , Biofilmes/crescimento & desenvolvimento , Bactérias/metabolismo , Microbiota , Proteobactérias/metabolismo
14.
Econ Hum Biol ; 54: 101410, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38908266

RESUMO

This paper studies the potential link between the biological evolution of populations and present-day economic interactions by estimating the correlation of shared ancestry among populations with cross-border capital and human flows. To this end, we employ the new concept of genetic distance, based on (dis)similarity of neutral gene alleles, to quantify shared ancestry. We then incorporate the genetic distance measure into an augmented gravity model, traditionally used to analyze the effect of geographical distance on bilateral exchange. Our analysis focuses on bilateral foreign direct investment (FDI) and migration across 135 countries and we use both linear regression techniques as well as the Poisson Pseudo-Maximum Likelihood Estimator to account for any non-linearities in the model. Our results show that a 1% increase in genetic distance reduces FDI flows by 0.08% while controlling for other distance constructs and factors associated with global capital and human movement. Genetic distance also has a negative effect on migration, where a 1% increase in genetic distance reduces migration flows by 0.22%, with all other things remaining constant. Our study, therefore, links shared ancestry with economic behavior, showing how historical connections are associated with current economic exchanges among nations. Additionally, recognizing that ancestral ties are outside human control, we examine policy measures that help nations overcome such distance barriers. Our findings show that strengthening a nation's institutional quality and adherence to the rule of law can effectively mitigate any negative correlation of distance constructs with economic exchanges. These insights suggest that prudent policies to foster a stable business environment are essential for any nation to attract FDI and human capital, even from geographically or genetically distant nations.


Assuntos
Genética Populacional , Humanos , Emigração e Imigração , Investimentos em Saúde
15.
J Affect Disord ; 362: 152-160, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38945403

RESUMO

BACKGROUND: The COVID-19 pandemic has had situational impacts and induced various psychological responses among residents. The present study aims to analyze the network structure of psychological responses to the pandemic and their relationships with situational impact, resilience, and well-being through a network approach. METHODS: An online survey recruited 1122 residents (mean age = 32.5 years, 65.4 % female) in Hong Kong from October 2020 to October 2021. The participants completed the Mental Impact and Distress Scale: Psychological Response (MIDc-PR) and other validated measures. Gaussian graphical modeling was conducted in R to identify the central MIDc-PR symptoms and their bridge linkages with situational impact, resilience, and well-being. RESULTS: In the MIDc-PR network, the central symptoms were 'Routine' and 'Images' for Anticipation and 'Tense' and 'Lonely' for Modulation, with 12 bridge edges between the two clusters. In the combined network, the MIDc-PR nodes showed 12 bridge edges with situational impact, particularly in the health domain. 'Concerned', 'Sleep', and 'Lonely' showed negative linkages with resilience; 'Unmotivated' and 'Trapped' showed negative linkages with well-being. The network models showed good levels of stability and did not differ significantly in network structure and global strength across gender and age groups. LIMITATIONS: The cross-sectional study design only allowed undirected associations in the network and could not model the within-subject effects. CONCLUSIONS: The study findings contributed to the literature by elucidating the network structure of psychological responses to the pandemic. The central and bridge symptoms have clinical implications as potential targets for future interventions.


Assuntos
COVID-19 , Resiliência Psicológica , Humanos , COVID-19/psicologia , COVID-19/epidemiologia , Hong Kong/epidemiologia , Feminino , Masculino , Adulto , SARS-CoV-2 , Inquéritos e Questionários , Pessoa de Meia-Idade , Adulto Jovem , Pandemias , Saúde Mental , Solidão/psicologia , Angústia Psicológica , Adolescente , Estudos Transversais , Análise de Rede Social
16.
Molecules ; 29(10)2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38792038

RESUMO

Lignin, the largest non-carbohydrate component of lignocellulosic biomass, is also a recalcitrant component of the plant cell wall. While the aerobic degradation mechanism of lignin has been well-documented, the anaerobic degradation mechanism is still largely elusive. In this work, a versatile facultative anaerobic lignin-degrading bacterium, Klebsiella aerogenes TL3, was isolated from a termite gut, and was found to metabolize a variety of carbon sources and produce a single kind or multiple kinds of acids. The percent degradation of alkali lignin reached 14.8% under anaerobic conditions, and could reach 17.4% in the presence of glucose within 72 h. Based on the results of infrared spectroscopy and 2D nuclear magnetic resonance analysis, it can be inferred that the anaerobic degradation of lignin may undergo the cleavage of the C-O bond (ß-O-4), as well as the C-C bond (ß-5 and ß-ß), and involve the oxidation of the side chain, demethylation, and the destruction of the aromatic ring skeleton. Although the anaerobic degradation of lignin by TL3 was slightly weaker than that under aerobic conditions, it could be further enhanced by adding glucose as an electron donor. These results may shed new light on the mechanisms of anaerobic lignin degradation.


Assuntos
Lignina , Lignina/metabolismo , Anaerobiose , Glucose/metabolismo , Klebsiella/metabolismo , Biomassa , Biodegradação Ambiental , Animais
17.
New Phytol ; 243(6): 2146-2156, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38736202

RESUMO

Unraveling the mechanisms of home-field advantage (HFA) is essential to gain a complete understanding of litter decomposition processes. However, knowledge of the relationships between HFA effects and microbial communities is lacking. To examine HFA effects on litter decomposition, we identified the microbial communities and conducted a reciprocal transplant experiment, including all possible combinations of soil and litter, between sites at two elevations in cool-temperate forests. Soil origin, rather than HFA, was an important factor in controlling litter decomposition processes. Microbiome-wide association analyses identified litter fungi and bacteria specific to the source soil, which completely differed at a low taxonomic level between litter types. The relative abundance of these microbes specific to source soil was positively correlated with litter mass loss. The results indicated that the unique relationships between plant litter and soil microbes through plant-soil linkages drive litter decomposition processes. In the short term, soil disturbances resulting from land-use changes have the potential to disrupt the effect of soil origin and hinder the advancement of litter decomposition. These findings contribute to an understanding of HFA mechanisms and the impacts of land-use change on decomposition processes in forest ecosystems.


Assuntos
Folhas de Planta , Microbiologia do Solo , Folhas de Planta/microbiologia , Folhas de Planta/metabolismo , Fungos/fisiologia , Bactérias/metabolismo , Microbiota/fisiologia , Solo/química , Florestas
18.
Angew Chem Int Ed Engl ; 63(26): e202404738, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38634674

RESUMO

Electrocatalytic carbon dioxide reduction reaction (CO2RR) to produce ethylene (C2H4) is conducive to sustainable development of energy and environment. At present, most electrocatalysts for C2H4 production are limited to the heavy metal copper, meanwhile, achieving metal-free catalysis remains a challenge. Noted piperazine with sp3 N hybridization is beneficial to CO2 capture, but CO2RR performance and mechanism have been lacking. Herein, based on linkage engineering, we construct a novel high-density sp3 N catalytic array via introducing piperazine into the crystalline and microporous aminal-linked covalent organic frameworks (COFs). Thanks to its high sp3 N density, strong CO2 capture capacity and great hydrophilicity, aminal-linked COF successfully achieves the conversion of CO2 to C2H4 with a Faraday efficiency up to 19.1 %, which is stand out in all reported metal-free COF electrocatalysts. In addition, a series of imine-linked COFs are synthesized and combined with DFT calculations to demonstrate the critical role of sp3 N in enhancing the kinetics of CO2RR. Therefore, this work reveals the extraordinary potential of linkage engineering in COFs to break through some catalytic bottlenecks.

19.
Small ; 20(34): e2311472, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38651243

RESUMO

Covalent organic frameworks (COFs), which have layered stacking structures, extended π-conjugation, and periodic frameworks have become a promising class of materials for a wide range of applications. However, their synthetic pathways frequently need high temperatures, enclosed systems under high pressures, an inert atmosphere, and extended reaction time, which restrict their practicality in real-world applications. Herein, the use of gamma irradiation is presented to synthesize highly crystalline COFs at room temperature under an open-air condition within a short time. This is demonstrated that there is no significant difference in crystallinity of COFs by gamma irradiation under air, N2 or Ar atmosphere conditions. Moreover, this approach can successfully fabricate COFs in the vessel with different degrees of transparency or even in a plastic container. Importantly, this strategy is applicable not only to imine linkage of COFs but also effective to the imide linkages of COFs. Most importantly, these COFs demonstrate improved crystallinity, surface area, and thermal stability in comparison to the corresponding materials synthesized via the solvothermal method. Finally, a COF synthesized through gamma irradiation exhibits remarkable photocatalytic activity in promoting the sacrificial hydrogen evolution from water, displaying a more catalytic efficiency compared with that of its solvothermal analogue.

20.
Nutrients ; 16(7)2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38612959

RESUMO

Measures of beliefs and attitudes toward food have generally been limited to the measurement of more pathological eating attitudes (e.g., disordered eating). The Food Life Questionnaire (FLQ) and its short form (FLQ-SF) were developed to examine attitudes toward a broader range of foods; however, the factor structure of the FLQ-SF was not confirmed in any study with young women. In the present study, we performed a psychometric evaluation of the Brazilian Portuguese translation of the FLQ-SF in a sample of 604 women. We evaluated the factor structure using a two-step, split-sample exploratory and confirmatory factor analytic approach. Results supported a four-factor structure (i.e., weight concern, diet-health orientation, belief in a diet-health linkage, and food and pleasure) with 18 items (χ2/df = 2.09; CFI = 0.95; TLI = 0.94; RMSEA = 0.05 (90% CI = 0.04; 0.06; p > 0.05); and SRMR = 0.08). Additionally, we found good internal consistency for all FLQ-SF subscales (McDonald's ω = 0.79-0.89) and convergent validity with measures of feelings, beliefs, and behaviors involved in food attitudes. Collectively, these results support the use of the FLQ-SF in Brazilian women and provide a foundation to expand the literature on beliefs and attitudes toward food in this population.


Assuntos
Emoções , Alimentos , Adulto , Humanos , Feminino , Brasil , Psicometria , Etnicidade
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