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1.
Microorganisms ; 12(6)2024 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-38930593

RESUMO

Ochrobactrum anthropi (O. anthropi) is found in water, soil, plants and animals. Even though it has low virulence, it has increasingly been found to cause a number of infectious diseases in people with low immunity. The identification of O. anthropi mainly uses biochemical methods, such as the API 20NE or Vitek-2. The typing studies of O. anthropi have mainly utilized PFGE, rep-PCR, AFLP, 16s rDNA sequencing, RecA-PCR RFLP, and MALDI-TOF MS. This study aims to evaluate the polymorphisms of variable-number tandem-repeats (VNTRs) within genomic DNA of O. anthropi strains. The tandem repeats (TRs) in genomic DNA are discovered using Tandem Repeat Finder software (version 4.09). Twelve different VNTRs are designated and assigned to the nomenclature. The primers for PCR of 12 loci are designed. The PCR product size is converted to the number of tandem repeats in every locus. The relatedness of 65 O. anthropi strains from geographically different countries are analyzed by means of 12-variable-number tandem-repeat analysis(MLVA-12). A total of 51 different genotypes are found in 65 O. anthropi strains. These strains, which were collected from the same environmental samples, hospitals, and countries, are clustered within the same or closely genotypes. The MLVA-12 assay has a good discriminatory power for species determination, typing of O. anthropi, and inferring the origin of bacteria.

2.
Chemistry ; : e202402019, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38923040

RESUMO

Photoacoustic (PA) tomography is an emerging biomedical imaging technology for precision cancer medicine. Conventional small-molecule PA probes usually exhibit a single PA signal and poor tumor targeting that lack the imaging reliability. Here, we introduce a series of cyanine/hemicyanine interconversion dyes (denoted Cy-HCy) for PA/fluorescent dual-mode probe development that features optimized ratiometric PA imaging and tunable tumor-targeting ability for precise diagnosis and resection of colorectal cancer (CRC). Importantly, Cy-HCy can be presented in cyanine (inherent tumor targeting and long NIR PA wavelength) and hemicyanine (poor tumor targeting and short NIR PA wavelength) by fine-tuning torsion angle and the ingenious transformation between cyanine and hemicyanine through regulation optically tunable group endows the NIR ratiometric PA and tunable tumor-targeting properties. To demonstrate the applicability of Cy-HCy dyes, we designed the first small-molecule tumor-targeting and NIR ratiometric PA probe Cy-HCy-H2S for precise CRC liver metastasis diagnosis, activated by H2S (a CRC biomarker). Using this probe, we not only visualized the subcutaneous tumor and liver metastatic cancers in CRC mouse models but also realized PA and fluorescence image-guided tumor excision. We expect that Cy-HCy will be generalized for creating a wide variety of inherently tumor-targeting NIR ratiometric PA probes in oncological research and practice.

3.
Front Pediatr ; 12: 1391229, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38938505

RESUMO

Rice body synovitis (RBS) is a rare disease, especially in children. Rheumatoid disorders and tuberculosis are the first two reasons for the formation of the RB. The diagnosis is mainly based on imaging and histopathological features. Herein, we report three cases of RBS in children diagnosed with congenital synovial chondromatosis, tuberculosis (unconfirmed), and ANA -positive juvenile idiopathic arthritis. Clinical features, radiographic findings, pathophysiology, treatment process, and prognosis were reviewed and documented meticulously to enhance cognition in this population and provide some references for clinicians in diagnosing and treating the disease.

5.
Int J Gen Med ; 17: 2527-2538, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38841128

RESUMO

Background: Emerging evidence suggests that systemic inflammatory and nutritional biomarkers, along with derived indices, could serve as predictors for sarcopenia in cancer population. This study aimed to compare these predictors, focusing on the nutritional risk index (NRI) and evaluate its diagnostic value, for sarcopenic patients without cancer. Methods: This cross-sectional retrospective study included 1674 participants. Sarcopenia is defined by skeletal muscle mass index (SMI). Laboratory data reflected the values of systemic inflammatory and nutritional biomarkers, from which the derived indices were calculated. Multiple logistic regression analysis, ROC curve analysis, and the Youden index were utilized to assess the association between these markers and sarcopenia and determine the cutoff value for predicting sarcopenia. Results: Among all participants (1110 men and 564 women, mean age 61.97 ± 9.83 years), 398 individuals were diagnosed with sarcopenia, indicating a prevalence of 23.78% in China's middle-aged and elderly population without cancer. Logistic regression analysis revealed significant associations between all biomarkers and derived indices with sarcopenia. Following adjustment for potential confounders, lower NRI values were significantly associated with a higher incidence of sarcopenia. For sarcopenia diagnosis, the area under the curve (AUC) for NRI was 0.769 ([95% CI, 0.742, 0.796], P < 0.001), with a cutoff value of 106.016, sensitivity of 75.6% and specificity of 66.1%. NRI demonstrated greater predictive advantage for sarcopenia incidence in men compared to women. Conclusion: A lower NRI value was associated with a higher prevalence of sarcopenia. NRI shows promise for early, rapid, and effective sarcopenia screening, particularly in China's middle-aged and elderly male population without cancer.

6.
Small ; : e2401767, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38847563

RESUMO

Porous graphene, including 2D and 3D porous graphene, is widely researched recently. One of the most attractive features is the proper utilization of graphene defects, which combine the advantages of both graphene and porous materials, greatly enriching the applications of porous graphene in biology, chemistry, electronics, and other fields. In this review, the defects of graphene are first discussed to provide a comprehensive understanding of porous graphene. Then, the latest advancements in the preparation of 2D and 3D porous graphene are presented. The pros and cons of these preparation methods are discussed in detail, providing a direction for the fabrication of porous graphene. Moreover, various superior properties of porous graphene are described, laying the foundation for their promising applications. Owing to its abundant morphology, wide distribution of pore size, and remarkable properties benefited from porous structure, porous graphene can not only promote molecular diffusion and electron transfer but also expose more active sites. Consequently, a serious of applications containing gas sieving, liquid separation, sensors, and supercapacitors, are presented. Finally, the challenges confronted during preparation and characterization of porous graphene are discussed, offering guidance for the future development of porous graphene in fabrication, characterization, properties, and applications.

7.
Small ; : e2403448, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38881353

RESUMO

Alcohol electrooxidation is pivotal for a sustainable energy economy. However, designing efficient electrocatalysts for this process is still a formidable challenge. Herein, palladium-selenium nanowires featuring distinct crystal phases: monoclinic Pd7Se2 and tetragonal Pd4.5Se for ethylene glycol electrooxidation reaction (EGOR) are synthesized. Notably, the supported monoclinic Pd7Se2 nanowires (m-Pd7Se2 NWs/C) exhibit superior EGOR activity, achieving a mass activity (MA) and specific activity (SA) of 10.4 A mgPd -1 (18.7 mA cm-2), which are 8.0 (6.7) and 10.4 (8.2) times versus the tetragonal Pd4.5Se and commercial Pd/C and surpass those reported in the literature. Furthermore, m-Pd7Se2 NWs/C displays robust catalytic activity for other alcohol electrooxidation. Comprehensive characterization and density functional theory (DFT) calculations reveal that the enhanced electrocatalytic performance is attributed to the increased formation of Pd0 on the high-index facets of the m-Pd7Se2 NWs, which lowers the energy barriers for the C─C bond dissociation in CHOHCHOH* and the CO* oxidation to CO2*. This study provides palladium-based alloy electrocatalysts exhibiting the highest mass activity reported to date for the electrooxidation of ethylene glycol, achieved through the crystalline phase engineering strategy.

8.
Inorg Chem ; 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38870427

RESUMO

The structural transformation of metal-organic frameworks (MOFs) has attracted increasing interests, which has not only produced various new structures but also served as a fantastic platform for MOF-based kinetic analysis. Multiple reaction conditions have been documented to cause structural transformation; nevertheless, central metal-induced topological alteration of MOFs is rare. Herein, we reported a structural transformation of a 2D layered Cd-MOF driven by Cd(II) ions. After being submerged in the aqueous solution of cadmium nitrate, the twofold interpenetrated 2D network of [Cd(hsb-2)(bdc)·5H2O]n [HSB-W10; bdc: 1,4-benzenedicarboxylate; hsb-2:1,2-bis(4'-pyridylmethylamino)-ethane] was converted into a novel noninterpenetrated 2D network [Cd1.5(hsb-2)(bdc)1.5(H2O)2·H2O]n (HSB-W16). This partial dissolution-recrystallization process was investigated by integrating controlled experiments, 1H NMR spectra, and photographic tracking analysis. Furthermore, a novel strategy combining in situ multicomponent dye encapsulation and central metal-triggered structural transformation was developed for the fabrication of MOF materials with white-light emission. By adopting this strategy, different dye guest molecules were concurrently introduced into the HSB-W16 host matrix, leading to a range of white-light-emitting MOF composites. This work will enable detailed studies of solid-state transformations and demonstrate a promising application prospect for structural transformation.

9.
Front Aging Neurosci ; 16: 1345918, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38863783

RESUMO

Parkinson's disease (PD) is neurodegenerative disease in middle-aged and elderly people with some pathological mechanisms including immune disorder, neuroinflammation, white matter injury and abnormal aggregation of alpha-synuclein, etc. New research suggests that white matter injury may be important in the development of PD, but how inflammation, the immune system, and white matter damage interact to harm dopamine neurons is not yet understood. Therefore, it is particularly important to delve into the crosstalk between immune cells in the central and peripheral nervous system based on the study of white matter damage in PD. This crosstalk could not only exacerbate the pathological process of PD but may also reveal new therapeutic targets. By understanding how immune cells penetrate through the blood-brain barrier and activate inflammatory responses within the central nervous system, we can better grasp the impact of structural destruction of white matter in PD and explore how this process can be modulated to mitigate or combat disease progression. Microglia, astrocytes, oligodendrocytes and peripheral immune cells (especially T cells) play a central role in its pathological process where these immune cells produce and respond to pro-inflammatory cytokines such as tumor necrosis factor (TNF-α), interleukin-1ß(IL-1ß) and interleukin-6(IL-6), and white matter injury causes microglia to become pro-inflammatory and release inflammatory mediators, which attract more immune cells to the damaged area, increasing the inflammatory response. Moreover, white matter damage also causes dysfunction of blood-brain barrier, allows peripheral immune cells and inflammatory factors to invade the brain further, and enhances microglia activation forming a vicious circle that intensifies neuroinflammation. And these factors collectively promote the neuroinflammatory environment and neurodegeneration changes of PD. Overall, these findings not only deepen our understanding of the complexity of PD, but also provide new targets for the development of therapeutic strategies focused on inflammation and immune regulation mechanisms. In summary, this review provided the theoretical basis for clarifying the pathogenesis of PD, summarized the association between white matter damage and the immune cells in the central and peripheral nervous systems, and then emphasized their potential specific mechanisms of achieving crosstalk with further aggravating the pathological process of PD.

10.
Neurosci Bull ; 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38896358

RESUMO

The kidneys are essential organs that help maintain homeostasis, and their function is regulated by the neural system. Despite the anatomical multi-synaptic connection between the central autonomic nuclei and the kidneys, it remains unclear whether there are any variations in neural connections between the nervous systems and the renal cortex and medulla in male and female mice. Here, we used the pseudorabies virus to map the central innervation network of the renal cortex and medulla in both sexes. The data revealed that specific brain regions displayed either a contralateral-bias or ipsilateral-bias pattern while kidney-innervating neurons distributed symmetrically in the midbrain and hindbrain. Sex differences were observed in the distribution of neurons connected to the left kidney, as well as those connected to the renal cortex and medulla. Our findings provide a comprehensive understanding of the brain-kidney network in both males and females and may help shed light on gender differences in kidney function and disease susceptibility in humans.

11.
Environ Int ; 189: 108783, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823156

RESUMO

BACKGROUND: Temperature affects influenza transmission; however, currently, limited evidence exists about its effect in China at the national and city levels as well as how temperature can be integrated into influenza interventions. METHODS: Meteorological, pollutant, and influenza data from 201 cities in mainland China between 2013 and 2018 were analyzed at both the city and national levels to investigate the relationship between temperature and influenza prevalence. We examined the impact of temperature on the time-varying reproduction number (Rt) using generalized additive quasi-Poisson regression models combined with the distributed lag nonlinear model. Threshold temperatures were determined for seven regions based on the early warning threshold of serious influenza outbreaks, set at Rt = 1.2. A multivariate random-effects meta-analysis was employed to assess region-specific associations. The excess risk (ER) index was defined to investigate the correlation between Rt and temperature, modified based on seasonal and regional characteristics. RESULTS: At the national level and in the central, northern, northwestern, and southern regions, temperature was found to be negatively correlated with relative risk, whereas the shapes of the data curves for the eastern, southwestern, and northeastern regions were not well defined. Low temperatures had an observable effect on influenza prevalence; however, the effects of high temperatures were not obvious. At an Rt of 1.2, the threshold temperatures for reaching a warning for serious influenza outbreaks were - 24.3 °C in the northeastern region, 16.6 °C in the northwestern region, and between 1℃ and 10 °C in other regions. CONCLUSION: The study findings revealed that temperature had a varying effect on influenza transmission trends (Rt) across different regions in China. By identifying region-specific temperature thresholds at Rt = 1.2, more effective early warning systems for influenza outbreaks could be tailored. These findings emphasize the significance of the region-specific adaptation of influenza prevention and control measures.


Assuntos
Cidades , Influenza Humana , Temperatura , China/epidemiologia , Influenza Humana/epidemiologia , Humanos , Cidades/epidemiologia , Prevalência , Estações do Ano
12.
Biomed Pharmacother ; 176: 116844, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823279

RESUMO

In contemporary times, tumors have emerged as the primary cause of mortality in the global population. Ongoing research has shed light on the significance of neurotransmitters in the regulation of tumors. It has been established that neurotransmitters play a pivotal role in tumor cell angiogenesis by triggering the transformation of stromal cells into tumor cells, modulating receptors on tumor stem cells, and even inducing immunosuppression. These actions ultimately foster the proliferation and metastasis of tumor cells. Several major neurotransmitters have been found to exert modulatory effects on tumor cells, including the ability to restrict emergency hematopoiesis and bind to receptors on the postsynaptic membrane, thereby inhibiting malignant progression. The abnormal secretion of neurotransmitters is closely associated with tumor progression, suggesting that focusing on neurotransmitters may yield unexpected breakthroughs in tumor therapy. This article presents an analysis and outlook on the potential of targeting neurotransmitters in tumor therapy.


Assuntos
Progressão da Doença , Neoplasias , Neurotransmissores , Humanos , Neurotransmissores/metabolismo , Neoplasias/patologia , Neoplasias/metabolismo , Animais , Neovascularização Patológica/patologia , Neovascularização Patológica/metabolismo
13.
Cancer Med ; 13(11): e7330, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38845478

RESUMO

OBJECTIVES: Patients with advanced colorectal cancer (CRC) have multiple concurrent physical and psychological symptoms. This study aimed to explore the relationship between anxiety, depression, and symptom burden in advanced CRC. METHODS: A multicenter cross-sectional study was conducted in 10 cancer centers from geographically and economically diverse sites in China. A total of 454 patients with advanced CRC completed the Hospital Anxiety and Depression Scale and the MD Anderson Symptom Inventory. Multiple regression analysis was applied to explore the relationship between anxiety, depression and symptom burden. RESULTS: About one-third of the patients showed symptoms of anxiety or depression. Patients with anxiety or depression reported significantly higher symptom burden than those without (p < 0.001). Patients with anxiety or depression reported a higher proportion of moderate-to-severe (MS) symptom number than those without (p < 0.001). About 52% of the patients with anxiety or depression reported at least three MS symptoms. The prevalence of MS symptoms was ranging from 7.3% (shortness of breath) to 22% (disturbed sleep), and in patients with anxiety or depression was 2-10 times higher than in those without (p < 0.001). Disease stage (ß = -2.55, p = 0.003), anxiety (ß = 15.33, p < 0.001), and depression (ß = 13.63, p < 0.001) were associated with higher symptom burden. CONCLUSIONS: Anxiety and depression in patients with advanced cancer correlated with higher symptom burden. Findings may lead oncology professionals to pay more attention to unrecognized and untreated psychological symptoms in symptom management for advanced cancer patients.


Assuntos
Ansiedade , Neoplasias Colorretais , Depressão , Humanos , Neoplasias Colorretais/psicologia , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/complicações , Masculino , Feminino , Estudos Transversais , Pessoa de Meia-Idade , Depressão/epidemiologia , Depressão/etiologia , Depressão/psicologia , Ansiedade/epidemiologia , Ansiedade/psicologia , Idoso , China/epidemiologia , Prevalência , Adulto , Idoso de 80 Anos ou mais , Qualidade de Vida , Carga de Sintomas
14.
bioRxiv ; 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38826190

RESUMO

Liquid-like protein condensates perform diverse physiological functions. Previous work showed that VASP, a processive actin polymerase, forms condensates that polymerize and bundle actin. To minimize their curvature, filaments accumulated at the inner condensate surface, ultimately deforming the condensate into a rod-like shape, filled with a bundle of parallel filaments. Here we show that this behavior does not require proteins with specific polymerase activity. Specifically, we found that condensates composed of Lamellipodin, a protein that binds actin but is not an actin polymerase, were also capable of polymerizing and bundling actin filaments. To probe the minimum requirements for condensate-mediated actin bundling, we developed an agent-based computational model. Guided by its predictions, we hypothesized that any condensate-forming protein that binds actin could bundle filaments through multivalent crosslinking. To test this idea, we added an actin-binding motif to Eps15, a condensate-forming protein that does not normally bind actin. The resulting chimera formed condensates that drove efficient actin polymerization and bundling. Collectively, these findings broaden the family of proteins that could organize cytoskeletal filaments to include any actin-binding protein that participates in protein condensation.

15.
Adv Mater ; : e2403961, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38830614

RESUMO

In recent years, conjugated polymers have received widespread attention due to their characteristic advantages of light weight, favorable solution processability, and structural modifiability. Among various conjugated polymers, fluorinated ones have developed rapidly to achieve high-performance n-type or ambipolar polymeric semiconductors. The uniqueness of fluorinated conjugated polymers contains the high coplanarity of their structures, lower frontier molecular orbital energy levels, and strong nonbonding interactions. In this review, first the fluorinated building blocks, including fluorinated benzene and thiophene rings, fluorinated B←N bridged units, and fluoroalkyl side chains are summarized. Subsequently, different synthetic methods of fluorinated conjugated polymers are described, with a special focus on their respective advantages and disadvantages. Then, with these numerous fluorinated structures and appropriate synthetic methods bear in mind, the properties and applications of the fluorinated conjugated polymers, such as cyclopentadithiophene-, amide-, and imide-based polymers, and B←N embedded polymers, are systematically discussed. The introduction of fluorine atoms can further enhance the electron-deficiency of the backbone, influencing the charge carrier transport performance. The promising fluorinated conjugated polymers are applied widely in organic field-effect transistors, organic solar cells, organic thermoelectric devices, and other organic opto-electric devices. Finally, the outlook on the challenges and future development of fluorinated conjugated polymers is systematically discussed.

16.
Polymers (Basel) ; 16(11)2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38891404

RESUMO

The aim of this study is the fabrication of unprecedented neuroelectrodes, replete with exceptional biological and electrical attributes. Commencing with the synthesis of polyethylene glycol and polyethyleneimine-modified iron oxide nanoparticles, the grafting of Dimyristoyl phosphatidylcholine was embarked upon to generate DMPC-SPION nanoparticles. Subsequently, the deposition of DMPC-SPIONs onto a nickel-chromium alloy electrode facilitated the inception of an innovative neuroelectrode-DMPC-SPION. A meticulous characterization of DMPC-SPIONs ensued, encompassing zeta potential, infrared spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction analyses. Evaluations pertaining to hemolysis and cytotoxicity were conducted to ascertain the biocompatibility and biosafety of DMPC-SPIONs. Ultimately, a comprehensive assessment of the biocompatibility, electrochemical properties, and electrophysiological signal acquisition capabilities of DMPC-SPION neuroelectrodes was undertaken. These findings conclusively affirm the exemplary biocompatibility, electrochemical capabilities, and outstanding capability in recording electrical signals of DMPC-SPION neuroelectrodes, with an astounding 91.4% augmentation in electrode charge and a noteworthy 13% decline in impedance, with peak potentials reaching as high as 171 µV and an impressive signal-to-noise ratio of 15.92. Intriguingly, the novel DMPC-SPION neuroelectrodes herald an innovative pathway towards injury repair as well as the diagnosis and treatment of neurological disorders.

17.
Plant Physiol ; 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38917229

RESUMO

Pollen germination and pollen tube elongation require rapid phospholipid production and remodeling in membrane systems that involve both de novo synthesis and turnover. Phosphatidic acid phosphohydrolase (PAH) and lysophosphatidylcholine acyltransferase (LPCAT) are two key enzymes in membrane lipid maintenance. PAH generates diacylglycerol (DAG), a necessary precursor for the de novo synthesis of phosphatidylcholine (PC), while LPCAT reacylates lysophosphatidylcholine (LPC) to PC and plays an essential role in the remodeling of membrane lipids. In this study, we investigated the synthetic defects of pah and lpcat mutations in sexual reproduction of Arabidopsis (Arabidopsis thaliana) and explored the prospect of pistil lipid provision to pollen tube growth. The combined deficiencies of lpcat and pah led to decreased pollen tube growth in the pistil and reduced male transmission. Interestingly, pistils of the lipid mutant dgat1 ameliorated the male transmission deficiencies of pah lpcat pollen. In contrast, pollination with a non-specific phospholipase C (NPC) mutant exacerbated the fertilization impairment of the pah lpcat pollen. Given the importance of DAG in lipid metabolism and its contrasting changes in the dgat1 and npc mutants, we further investigated whether DAG supplement in synthetic media could influence pollen performance. DAG was incorporated into phospholipids of germinating pollen and stimulated pollen tube growth. Our study provides evidence that pistil derived lipids contribute to membrane lipid synthesis in pollen tube growth, a hitherto unknown role in synergistic pollen-pistil interactions.

18.
J Environ Manage ; 365: 121506, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38901319

RESUMO

Straw biochar is a commonly recognized agricultural amendment that can improve soil quality and reduce carbon emissions while sequestering soil carbon. However, the mechanisms underlying biochar's effects on annual soil carbon emissions in seasonally frozen soil areas and intrinsic drivers have not been clarified. Here, a 2-y field experiment was conducted to investigate the effects of different biochar dosages (0, 15, and 30, t ha-1; B0 (CK), B15, and B30, respectively) on carbon emissions (CO2 and CH4) microbial colony count, and soil-environment factors. The study period was the full annual cycle, including the freeze-thaw period (FTP) and the crop growth period (CP). Structural equation modeling (SEM) was developed to reveal the key drivers and potential mechanisms of biochar on carbon emissions. Biochar application reduced soil carbon emissions, with the reduction rate positively related to the biochar application rate (B30 best). During FTP, the reduction rate was 11.5% for CO2 and 48.2% for CH4. During CP, the reduction rate was 17.9% for CO2 and 34.5% for CH4. Overall, compared with CK, B30 treatment had a significant effect on reducing total soil carbon emissions (P < 0.05), with an average decrease of 16.7% during the two-year test period. The study also showed that for soils with continuous annual cycles (FTP and CP), carbon emissions were best observed from 10:00-13:00. After two years of freeze-thaw cycling, biochar continued to improve soil physical and chemical properties, thereby increasing soil microbial colony count. Compared with B0, the B30 treatment significantly increased the total colony count by 74.3% and 263.8% during FTP and CP (P < 0.05). Structural equation modeling (SEM) indicated that, with or without biochar application, the soil physicochemical properties directly or indirectly affected soil CO2 and CH4 emission fluxes through microbial colony count. The total effects of biochar application on CO2 emission fluxes were 0.50 (P < 0.05) and 0.64 (P < 0.01), respectively, but there was no significant effect on CH4 emission fluxes (P > 0.05). Among them, soil water content (SWC), soil temperature (ST) and soil organic carbon (SOC) were the main environmental determinants of CO2 emission fluxes during the FTP and CP. The total effects were 0.57, 0.65, and 0.53, respectively. For CH4, SWC, soil salinity (SS) and actinomycete colony count were the main environmental factors affecting its emission. The total effects were 0.50, 0.45, 0.44, respectively. For freeze-thaw alternating soils, the application of biochar is a feasible option for addressing climate change through soil carbon sequestration and greenhouse gas emissions mitigation. Soil water-heat-salt-fertilization and microbial communities are important for soil carbon emissions as the reaction matrix and main participants of soil carbon and nitrogen biochemical transformation.

19.
mSystems ; : e0051324, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38904399

RESUMO

Mixotrophy is an important trophic strategy for bacterial survival in the ocean. However, the global relevance and identity of the major mixotrophic taxa remain largely elusive. Here, we combined phylogenetic, metagenomic, and metatranscriptomic analyses to characterize ubiquitous Arcobacteraceae based on our deep-sea in situ incubations and the global data. The phylogenomic tree of Arcobacteraceae is divided into three large clades, among which members of clades A and B are almost all from terrestrial environments, while those of clade C are widely distributed in various marine habitats in addition to some terrestrial origins. All clades harbor genes putatively involved in chitin degradation, sulfide oxidation, hydrogen oxidation, thiosulfate oxidation, denitrification, dissimilatory nitrate reduction to ammonium, microaerophilic respiration, and metal (iron/manganese) reduction. Additionally, in clade C, more unique pathways were retrieved, including thiosulfate disproportionation, ethanol fermentation, methane oxidation, fatty acid oxidation, cobalamin synthesis, and dissimilatory reductions of sulfate, perchlorate, and arsenate. Within this clade, two mixotrophic Candidatus genera represented by UBA6211 and CAIJNA01 harbor genes putatively involved in the reverse tricarboxylic acid pathway for carbon fixation. Moreover, the metatranscriptomic data in deep-sea in situ incubations indicated that the latter genus is a mixotroph that conducts carbon fixation by coupling sulfur oxidation and denitrification and metabolizing organic matter. Furthermore, global metatranscriptomic data confirmed the ubiquitous distribution and global relevance of Arcobacteraceae in the expression of those corresponding genes across all oceanic regions and depths. Overall, these results highlight the contribution of previously unrecognized Arcobacteraceae to carbon, nitrogen, and sulfur cycling in global oceans.IMPORTANCEMarine microorganisms exert a profound influence on global carbon cycling and ecological relationships. Mixotrophy, characterized by the simultaneous utilization of both autotrophic and heterotrophic nutrition, has a significant impact on the global carbon cycling. This report characterizes a group of uncultivated bacteria Arcobacteraceae that thrived on the "hot time" of bulky particulate organic matter and exhibited mixotrophic strategy during the in situ organic mineralization. Compared with clades A and B, more unique metabolic pathways were retrieved in clade C, including the reverse tricarboxylic acid pathway for carbon fixation, thiosulfate disproportionation, methane oxidation, and fatty acid oxidation. Global metatranscriptomic data from the Tara Oceans expeditions confirmed the ubiquitous distribution and extensive transcriptional activity of Arcobacteraceae with the expression of genes putatively involved in carbon fixation, methane oxidation, multiple sulfur compound oxidation, and denitrification across all oceanic regions and depths.

20.
Environ Manage ; 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38867057

RESUMO

The development of renewable energy has become an important means for the world to cope with climate change, ensure energy security, and protect the ecological environment. Using the panel data of 30 provinces in China from 2013 to 2021, this study used the mediating effect model and the spatial Durbin model (SDM) to explore the mechanism and spatial effects of renewable energy development on China's regional carbon emission reduction. The results show that: (1) Renewable energy development can help to reduce carbon emission intensity. (2) The results of mechanism analysis show that renewable energy development reduces carbon intensity by improving energy structure, promoting industrial structure optimization, and industrial structure upgrading. (3) The development of renewable energy can not only reduce the local carbon intensity but also have a positive spillover effect on the carbon intensity of neighboring regions. (4) Further analysis shows that the long-term effect of renewable energy development on carbon emissions is greater than the short-term effect. At the same time, the heterogeneity analysis shows that compared with the Yellow River basin, the development of renewable energy has a significant carbon emission reduction effect in the Yangtze River Economic Belt region. Energy-rich areas fall into the "resource curse", which makes the carbon emission reduction effect of renewable energy development not significant. This paper has certain reference significance for promoting reasonable decomposition between regions and formulating renewable energy development policies.

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