Toward the Production of Super Graphene.

The quality requirements of graphene depend on the applications. Some have a high tolerance for graphene quality and even require some defects, while others require graphene as perfect as possible to achieve good performance. So far, synthesis of large-area graphene films by chemical vapor deposition of carbon precursors on metal substrates, especially on Cu, remains the main way to produce high-quality graphene, which has been significantly developed in the past 15 years. However, although many prototypes are demonstrated, their performance is still more or less far from the theoretical property limit of graphene. This review focuses on how to make super graphene, namely graphene with a perfect structure and free of contaminations. More specially, this study focuses on graphene synthesis on Cu substrates. Typical defects in graphene are first discussed together with the formation mechanisms and how they are characterized normally, followed with a brief review of graphene properties and the effects of defects. Then, the synthesis progress of super graphene from the aspects of substrate, grain size, wrinkles, contamination, adlayers, and point defects are reviewed. Graphene transfer is briefly discussed as well. Finally, the challenges to make super graphene are discussed and a strategy is proposed.

Deciphering the multifaceted effects of artificial sweeteners on body health and metabolic functions: a comprehensive review and future perspectives.

As the rates of chronic diseases such as obesity and diabetes rise worldwide, there is a growing demand for low-calorie or no-calorie sweeteners to reduce sugar intake without sacrificing the sweetness of foods and beverages. Artificial sweeteners have become indispensable as substitutes for sugar due to their high sweetening power and low impact on blood sugar levels and are used in a variety of low-calorie foods and beverages. Although artificial sweeteners offer an alternative for reducing sugar intake while maintaining sweetness, research into their long-term health effects, particularly at high doses, is ongoing, further scientific research and regulatory review are needed to clarify these potential health risks. This article reviews the latest research on the health effects of artificial sweeteners, based on recent studies, introduces the classification, performance, and safety standards for artificial sweeteners, analyses their potential harms to the nervous, immune, and circulatory systems, reproductive system, as well as their effects on gut microbiota, liver function, cancer, diabetes, and obesity. In addition, consumer perceptions of artificial sweeteners and future research directions are discussed, providing insights into current research controversies and knowledge gaps, as well as the health research and market application of artificial sweeteners.

Study on a Pig Vocalization Classification Method Based on Multi-Feature Fusion.

To improve the classification of pig vocalization using vocal signals and improve recognition accuracy, a pig vocalization classification method based on multi-feature fusion is proposed in this study. With the typical vocalization of pigs in large-scale breeding houses as the research object, short-time energy, frequency centroid, formant frequency and first-order difference, and Mel frequency cepstral coefficient and first-order difference were extracted as the fusion features. These fusion features were improved using principal component analysis. A pig vocalization classification model with a BP neural network optimized based on the genetic algorithm was constructed. The results showed that using the improved features to recognize pig grunting, squealing, and coughing, the average recognition accuracy was 93.2%; the recognition precisions were 87.9%, 98.1%, and 92.7%, respectively, with an average of 92.9%; and the recognition recalls were 92.0%, 99.1%, and 87.4%, respectively, with an average of 92.8%, which indicated that the proposed pig vocalization classification method had good recognition precision and recall, and could provide a reference for pig vocalization information feedback and automatic recognition.

Crop diversification promotes soil aggregation and carbon accumulation in global agroecosystems: A meta-analysis.

Soil aggregation contributes to the stability of soil structure and the sequestration of soil organic carbon (SOC), making it an important indicator of soil health in agroecosystems. Crop diversification is considered a rational management practice for promoting sustainable agriculture. However, the complexity of cropping systems and crop species across different regions limits our comprehensive understanding of soil aggregation and associated carbon (C) content under crop diversification. Therefore, we conducted a meta-analysis by integrating 1924 observations from three diversification strategies (cover crops, crop rotation, and intercropping) in global agroecosystems to explore the effects of crop diversification on soil aggregates and associated C content. The results showed that compared to monoculture, crop diversification significantly increased the mean weight diameter and bulk soil C by 7.5% and 3.3%, respectively. Furthermore, there was a significant increase in the proportion of macroaggregates and their associated C content by 5.0% and 12.5%, while there was a significant decrease in the proportion of microaggregates as well as silt-clay fractions along with their associated C under crop diversification. Through further analysis, we identified several important factors that influence changes in soil aggregation and C content induced by crop diversification including climatic conditions, soil properties, crop species, and agronomic practices at the experimental sites. Interestingly, no significant differences were found among the three cropping systems (cover crops, crop rotation, and intercropping), while the effects induced by crop diversifications showed relatively consistent results for monoculture crops as well as additive crops and crop diversity. Moreover, the impact of crop diversification on soil aggregates and associated C content is influenced by soil properties such as pH and SOC. In general, our findings demonstrate that crop diversification promotes soil aggregation and enhances SOC levels in agroecosystems worldwide.

Recombinant human brain natriuretic peptide attenuates ischemic brain injury in mice by inhibiting oxidative stress and cell apoptosis via activation of PI3K/AKT/Nrf2/HO-1 pathway.

Ischemic stroke followed by cerebral artery occlusion is a main cause of chronic disability worldwide. Recombinant human brain natriuretic peptide (rhBNP) has been reported to alleviate sepsis-induced cognitive dysfunction and brain I/R injury. However, the function and molecular mechanisms of rhBNP in ischemic brain injury have not been clarified. For establishment of an animal model of ischemic brain injury, C57BL/6 mice were treated with middle cerebral artery occlusion (MCAO) surgery for 1 h and reperfusion for 24 h. After subcutaneous injection of rhBNP into model mice, neurologic deficits were assessed by evaluating behavior of mice according to Longa scoring system, and TTC staining was utilized to determine the brain infarct size of mice. The levels of oxidative stress markers, superoxide dismutase (SOD), catalase (CAT), glutathione (GSH) and malondialdehyde (MDA), were detected in hippocampal tissues of mice by corresponding kits. Cell apoptosis in hippocampus tissues was examined by TUNEL staining. Protein levels of antioxidant enzymes (HO-1 and NQO1) in cerebral cortex, apoptotic markers (Bax, Bcl-2, and cleaved caspase), and PI3K/AKT pathway-associated factors in hippocampus were tested by western blot analysis. The results revealed that injection of rhBNP decreased neurologic deficit scores, the percent of brain water content, and infarct volume. Additionally, rhBNP downregulated MDA level, upregulated the levels of SOD, CAT, and GSH in hippocampus of mice, and increased protein levels of HO-1 and NQO1 in the cortex. Cell apoptosis in hippocampus tissues of model mice was inhibited by rhBNP which was shown as the reduced TUNEL-positive cells, the decreased Bax, cleaved caspase-3, and cleaved caspase-9 protein levels, and the enhanced Bcl-2 protein level. In addition, rhBNP treatment activated the PI3K/AKT signaling pathway and upregulated the protein levels of HO-1 and NRF2. Overall, rhBNP activates the PI3K/AKT/HO-1/NRF2 pathway to attenuate ischemic brain injury in mice after MCAO by suppression of cell apoptosis and oxidative stress.

Hyperoside Attenuates Sepsis-Induced Acute Lung Injury (ALI) through Autophagy Regulation and Inflammation Suppression.

Background: Sepsis mortality and morbidity are aggravated by acute lung injury (ALI) or acute respiratory distress syndrome. Published studies have discovered that hyperoside (HYP) has an anti-inflammatory and therapeutic effect in many diseases. However, whether HYP treatment can attenuate sepsis-induced ALI is still obscure. Methods: In this study, a cecal ligation and puncture (CLP)-induced sepsis mouse model was constructed. The mouse lungs were harvested and assessed using proteomics, immunohistochemistry, immunofluorescence, and enzyme-linked immunosorbent assay for pro-inflammatory cytokines. Human lung microvascular endothelial cells (HLMVECs) were induced with lipopolysaccharide (LPS) for the in vitro model. Results: The results showed that HYP treatment attenuated sepsis-induced ALI through an increased survival rate, decreased inflammatory factor expression, and lung tissue apoptosis. At the same time, HYP pretreatment restored angiogenesis in CLP-induced mouse lung tissues. Proteomics detection showed that Atg13 played a vital role in HYP-mediated protection against sepsis-induced ALI. The in vitro experiment showed HYP treatment attenuated LPS-induced HLMVEC damage by regulating Atg13-mediated autophagy. Inhibiting autophagy or silencing Atg13 reversed the protective effect of HYP against sepsis-induced ALI. Conclusion: Taken together, we conclude that HYP attenuated sepsis-induced ALI by regulating autophagy and inhibiting inflammation.

Incentive policies for transboundary marine spatial planning: an evolutionary game theory-based analysis.

Marine spatial planning (MSP), which is a step-by-step approach for the ecosystem-based management (EBM) of global oceans, enables human activity and marine and coastal ecosystems conservation to occur simultaneously. It contributes to the implementation of the 2030 Agenda, particularly Sustainable Development Goal 14. However, the MSP, supposed as a transboundary policy-making process, is hampered by obstacles. Although existing studies have revealed significant obstacles and enablers for transboundary marine spatial planning (TMSP), they have not analyzed how these factors affect government decision-making. To fill this gap, this paper takes the Xiamen-Kinmen Sea area in China as an example and analyses the interaction between the Xiamen-Zhangzhou-Quanzhou (XZQ) governments, the Kinmen government, and an introduced transboundary institution using evolutionary game theory. Numerical simulation is used to analyse the impact of influencing factors on the behaviors of different actors. The results demonstrate that: (1) the initial probability of the three parties directly affect the final stability; (2) net benefits have a positive incentivizing effect on the performance of the Promotion Group; (3) the value of eco-environmental losses reflects the urgency of collaborative governance by implementing TMSP; (4) transaction costs do not undermine collaboration, but do reduce the willingness of governments to participate if they are too high; and (5) the appropriate value of the transaction cost allocation coefficient should not exceed 0.9. This research may serve as an essential reference for the Xiamen-Kinmen Sea area for implementing EBM and provide general insights into the design of incentive policy recommendations for other regions for developing TMSP in shared waters.

A Method for Detecting the Randomness of Barkhausen Noise in a Material Fatigue Test Using Sensitivity and Uncertainty Analysis.

The magnetic Barkhausen noise (MBN) signal provides interesting clues about the evolution of microstructure of the magnetic material (internal stresses, level of degradation, etc.). This makes it widely used in non-destructive evaluation of ferromagnetic materials. Although researchers have made great effort to explore the intrinsic random characteristics and stable features of MBN signals, they have failed to provide a deterministic definition of the stochastic quality of the MBN signals. Because many features are not reproducible, there is no quantitative description for the stochastic nature of MBN, and no uniform standards to evaluate performance of features. We aim to make further study on the stochastic characteristics of MBN signal and transform it into the quantification of signal uncertainty and sensitivity, to solve the above problems for fatigue state prediction. In the case of parameter uncertainty in the prediction model, a prior approximation method was proposed. Thus, there are two distinct sources of uncertainty: feature(observation) uncertainty and model uncertainty were discussed. We define feature uncertainty from the perspective of a probability distribution using a confidence interval sensitivity analysis, and uniformly quantize and re-parameterize the feature matrix from the feature probability distribution space. We also incorporate informed priors into the estimation process by optimizing the Kullback-Leibler divergence between prior and posterior distribution, approximating the prior to the posterior. Thus, in an insufficient data situation, informed priors can improve prediction accuracy. Experiments prove that our proposed confidence interval sensitivity analysis to capture feature uncertainty has the potential to determine the instability in MBN signals quantitatively and reduce the dispersion of features, so that all features can produce positive additive effects. The false prediction rate can be reduced to almost 0. The proposed priors can not only measure model parameter uncertainties but also show superior performance similar to that of maximum likelihood estimation (MLE). The results also show that improvements in parameter uncertainties cannot be directly propagated to improve prediction uncertainties.

Sample Preparation in Centrifugal Microfluidic Discs for Human Serum Metabolite Analysis by Surface Assisted Laser Desorption/Ionization Mass Spectrometry.

We introduce a centrifugal microfluidic disc that accepts a small volume in (∼5 µL), performs sample cleanup on human serum samples, and delivers a small volume out, for subsequent metabolite analysis by surface assisted laser desorption/ionization (SALDI) mass spectrometry (MS) or hydrophilic interaction liquid chromatography (HILIC)-MS. The centrifugal microfluidic disc improves the MS results by removing proteins and lipids from serum. In the case of SALDI-MS, sample background electrolytes are segregated from analytes during the spotting process by the action of the SALDI-chip during drying, for further cleanup, while HILIC separates the salts in HILIC-MS. The resulting mass spectra of disc-prepared samples show a clean background and high signal-to-noise ratio for metabolite peaks. Several representative ionic metabolites from human serum samples were successfully quantified. The performances of the sample preparation disc for SALDI-MS and HILIC-MS were assessed and were comparable. Reproducibility, sample bias, and detection limits for SALDI-MS compared well to ultrafiltration sample preparation.

Liver Plays a Major Role in FGF-21 Mediated Glucose Homeostasis.

BACKGROUND/AIMS: The liver is a vital organ in vertebrates and has a wide range of functions, including glucose absorption, glycogen storage and glucose production. Fibroblast growth factor (FGF)-21 is a metabolic regulator that is primarily produced by the liver. In this paper, we studied the effect of FGF-21 on glucose metabolism in the liver. METHODS: The glucose uptake of cells was detected by 2-Deoxy-d-[3H] glucose; the synergy between insulin and FGF-21 was evaluated. The mRNA expression of GLUT1-4, G6Pase and PEPCK was detected by real-time PCR. Glycogen synthesis was examined by the anthrone method. Blood samples to monitor glucose in db/db diabetic mice were obtained by tail snip. Glucose metabolism in the liver and adipose tissues was observed by fluorescence microscopy. RESULTS: In this study, FGF-21 stimulated glucose uptake by liver cells in both a dose and time-dependent manner, and at the same time, FGF-21 specifically stimulated GLUT1 expression in the liver cells. Furthermore, FGF-21 demonstrated a synergistic effect with insulin on glucose absorption, which is in accordance with enhanced GLUT-1 and -4 expression. Treatment with FGF-21 increased glycogen storage in liver cells. Consistent with in vitro results, FGF-21 lowered the plasma glucose level and stimulated GLUT1 expression and glycogen synthesis in db/db diabetic mice. Simultaneously, FGF-21 inhibited the gene expression of G6Pase and PEPCK. CONCLUSION: Our results suggest that FGF-21 clears up plasma glucose by stimulating glucose absorption in the liver of diabetic animals and decreases glucose release from the liver by inhibiting gluconeogenesis. Overall, these data indicate that the liver is an important target organ of FGF-21 to regulate glucose metabolism.

Redox-dependent interactions between reduced/oxidized cytochrome c and cytochrome c oxidase evaluated by in-situ electrochemical surface plasmon resonance.

The interactions between the redox couple of cytochrome c (Cyt c) and cytochrome c oxidase (COX) were investigated at a mimic redox-modulated interface by using an electrochemical surface plasmon resonance (EC-SPR) system. Although early studies of the binding between COX and Cyt c have been conducted using several techniques in homogeneous solutions, a problem still inherent is that ferro-cytochrome c (Cyt c red), the reduced form of Cyt c, can be easily oxidized into ferri-cytochrome c (Cyt c ox) and adversely impact the accuracy and reproducibility of the binding measurements. In order to realize reliable redox-dependent binding tests, here the Cyt c red is quantitatively electro-generated from Cyt c ox by in situ cathodic polarization in a flow cell. Then the kinetic and dissociation constants of the bindings between COX and Cyt c red/Cyt c ox can be evaluated accurately. In this study, the values of association/dissociation rate constants (k a, k d) for both COX/Cyt c red and COX/Cyt c ox were obtained. The dissociation constants, K D, were finally calculated as 3.33 × 10(-8) mol · L(-1) for COX/Cyt c red and 4.25 × 10(-5) mol · L(-1) for COX/Cyt c ox, respectively. In-situ EC-SPR is promising for better mimicking the in vivo condition that COX is embedded in the inner mitochondrial membrane and Cyt c acts as an electron shuttle in the mobile phase. It is an effective method for the investigation of redox-dependent biomolecular interactions. Graphical Abstract Schematic representation of the experimental designs using EC-SPR system. (a) the Au-Cys-COX SPR chip with SAM layers. (b) redox-modulated Cyt c and its binding onto pre-immobilized COX.

Noninvasive Transdermal Administration of mRNA Vaccines Encoding Multivalent Neoantigens Effectively Inhibits Melanoma Growth.

It is difficult to obtain specific tumor antigens, which is one of the main obstacles in the development of tumor vaccines. The vaccines containing multivalent antigens are thought to be more effective in antitumor therapy. In this study, a mRNA encoding three neoantigens of melanoma were prepared and encapsulated into the mannosylated chitosan-modified ethosomes (EthsMC) to obtain a multivalent mRNA vaccine (MmRV) for transcutaneous immunization (TCI). MmRV can effectively induce maturation of dendritic cells, with a better performance than mRNA of a single neoantigen. TCI patches (TCIPs) loading MmRV or siRNA against PDL1 (siPDL1) were prepared and applied to the skin of melanoma-bearing mice. The results showed that TCIPs significantly increase the levels of TNF-α, IFN-γ, and IL-12 in both plasma and tumor tissues, inhibit tumor growth, as well as promote infiltration of CD4+ and CD8+ T cells in the tumor tissues. Furthermore, the combination of MmRV and siPDL1 showed much better antitumor effects than either monotherapy, suggesting a synergistic effect between the vaccine and PDL1 blocker. In addition, the treatment with the TCIPs did not cause damage to the skin, blood, and vital organs of the mice, showing good biosafety. To the best of our knowledge, this work is the first to construct a noninvasive TCI system containing MmRV and siPDL1, providing a convenient and promising approach for tumor treatment.

Single-cell atlas reveals the immunosuppressive microenvironment and Treg cells landscapes in recurrent Glioblastoma.

Patients diagnosed with glioblastoma (GBM) have the most aggressive tumor progression and lethal recurrence. Research on the immune microenvironment landscape of tumor and cerebrospinal fluid (CSF) is limited. At the single-cell level, we aim to reveal the recurrent immune microenvironment of GBM and the potential CSF biomarkers and compare tumor locations. We collected four clinical samples from two patients: malignant samples from one recurrent GBM patient and non-malignant samples from a patient with brain tumor. We performed single-cell RNA sequencing (scRNA-seq) to reveal the immune landscape of recurrent GBM and CSF. T cells were enriched in the malignant tumors, while Treg cells were predominately found in malignant CSF, which indicated an inhibitory microenvironment in recurrent GBM. Moreover, macrophages and neutrophils were significantly enriched in malignant CSF. This indicates that they an important role in GBM progression. S100A9, extensively expressed in malignant CSF, is a promising biomarker for GBM diagnosis and recurrence. Our study reveals GBM's recurrent immune microenvironment after chemoradiotherapy and compares malignant and non-malignant CSF samples. We provide novel targets and confirm the promise of liquid CSF biopsy for patients with GBM.

Clinical application of a connection device consisting of a bag valve mask and nebulizer in first aid: Two case reports.

In clinical practice, several emergencies may threaten the life of patients, and these emergencies can be unpredictable and challenging. During the coronavirus disease 2019 pandemic, in January 2023, a patient developed respiratory distress caused by coronavirus, but was unable to access respiratory support due to shortages of medical resources, intensive care unit beds and ventilators. The medical staff quickly created a portable high-flow atomized oxygen therapy apparatus consisting of a simple breathing bag connected to a nebulizer to provide breathing support. In addition, the Ambulatory Surgery Center, The First Affiliated Hospital of Anhui Medical University (Hefei, China) witnessed a case of severe laryngeal spasm after tracheal extubation during the recovery period from general anesthesia. Due to the lack of an anesthesia machine nebulizer, the aforementioned device was used to provide oxygen under pressure and initiate treatment to quickly relieve the symptoms of laryngeal obstruction. The present case report describes how the medical staff quickly applied emergency airway management skills and knowledge to create a portable high-flow atomized oxygen therapy apparatus in a resource-poor setting to save the lives of two patients.

µPADs on Centrifugal Microfluidic Discs for Rapid Sample-to-Answer Salivary Diagnostics.

A fully integrated device for salivary detection with a sample-in-answer-out fashion is critical for noninvasive point-of-care testing (POCT), especially for the screening of contagious disease infection. Microfluidic paper-based analytical devices (µPADs) have demonstrated their huge potential in POCT due to their low cost and easy adaptation with other components. This study developed a generic POCT platform by integrating a centrifugal microfluidic disc with µPADs to realize sample-to-answer salivary diagnostics. Specifically, a custom centrifugal microfluidic disc integrated with µPADs is fabricated, which demonstrated a high efficiency in saliva treatment. To demonstrate the capability of the integrated device for salivary analysis, the SARS-CoV-2 Nucleocapsid (N) protein, a reliable biomarker for SARS-CoV-2 acute infection, is used as the model analyte. By the chemical treatment of the µPAD surface, and by optimizing the protein immobilization conditions, the on-disc µPADs were able to detect the SARS-CoV-2 N protein down to 10 pg mL-1 with a dynamic range of 10-1000 pg mL-1 and an assay time of 8 min. The integrated device was successfully used for the quantification of the N protein of pseudovirus in saliva with high specificity and demonstrated a comparable performance to the commercial paper lateral flow assay test strips.

An Automated Centrifugal Microfluidic Platform for Efficient Multistep Blood Sample Preparation and Clean-Up towards Small Ion-Molecule Analysis.

Sample preparation for mass spectroscopy typically involves several liquid and solid phase clean-ups, extractions, and other unit operations, which are labour-intensive and error-prone. We demonstrate a centrifugal microfluidic platform that automates the whole blood sample's preparation and clean-up by combining traditional liquid-phase and multiple solid-phase extractions for applications in mass spectroscopy (MS)-based small molecule detection. Liquid phase extraction was performed using methanol to precipitate proteins in plasma separated from a blood sample under centrifugal force. The preloaded solid phase composed of C18 beads then removed lipids with a combination of silica particles, which further cleaned up any remaining proteins. We further integrated the application of this sample prep disc with matrix-assisted laser desorption/ionization (MALDI) MS by using glancing angle deposition films, which further cleaned up the processed sample by segregating the electrolyte background from the sample salts. Additionally, hydrophilic interaction liquid chromatography (HILIC) MS was employed for detecting targeted free amino acids. Therefore, several representative ionic metabolites, including several amino acids and organic acids from blood samples, were analysed by both MALDI-MS and HILIC-MS to demonstrate the performance of this sample preparation disc. The fully automated blood sample preparation procedure only took 35 mins, with a throughput of three parallel units.

Characterization and application of a lytic jumbo phage ZPAH34 against multidrug-resistant Aeromonas hydrophila.

Aeromonas hydrophila is an emerging foodborne pathogen causing human gastroenteritis. Aeromonas species isolated from food such as seafood presented multidrug-resistance (MDR), raising serious concerns regarding food safety and public health. The use of phages to infect bacteria is a defense against drug-resistant pathogens. In this study, phage ZPAH34 isolated from the lake sample exerted lytic activity against MDR A. hydrophila strain ZYAH75 and inhibited the biofilm on different food-contacting surfaces. ZPAH34 has a large dsDNA genome of 234 kb which belongs to a novel jumbo phage. However, its particle size is the smallest of known jumbo phages so far. Based on phylogenetic analysis, ZPAH34 was used to establish a new genus Chaoshanvirus. Biological characterization revealed that ZPAH34 exhibited wide environmental tolerance, and a high rapid adsorb and reproductive capacity. Food biocontrol experiments demonstrated that ZPAH34 reduces the viable count of A. hydrophila on fish fillets (2.31 log) and lettuce (3.28 log) with potential bactericidal effects. This study isolated and characterized jumbo phage ZPAH34 not only enriched the understanding of phage biological entity diversity and evolution because of its minimal virion size with large genome but also was the first usage of jumbo phage in food safety to eliminate A. hydrophila.

Long-term plastic mulching decreases rhizoplane soil carbon sequestration by decreasing microbial anabolism.

Ridge-furrow with plastic mulching (RFPM) is a widely used agricultural practice in rain-fed farmlands. However, the impact of microbial related metabolism on soil organic carbon (SOC) is not fully understood. Amino sugar analysis, high-throughput sequencing, and high-throughput qPCR approaches are combined to investigate this topic, based on a long-term experiment. Treatments include flat planting without mulching (FP), ridge-furrow without mulching (RF), and RFPM. RFPM significantly decreases rhizoplane SOC contents, while bulk SOC contents change insignificantly across treatments. In terms of microbial metabolic pathways, RFPM decreases indicators of the in vivo metabolic pathway, whereas those of the ex vivo pathway are increased. In terms of microbial community features, core taxa module #1 is dominated by Sphingomonadaceae. These are putative high yield (Y) strategists, according to the microbial life-history strategy framework. They are closely related to the in vivo pathway and are most predictive for SOC; their abundance is highest under FP and lowest under RFPM. Core taxa module #2 is dominated by Chitinophagaceae, putative resource acquisition (A) strategists, that are closely related to the ex vivo pathway. Their abundance in the rhizoplane is highest under RFPM and lowest under FP. The RFPM-induced decline in SOC occurs simultaneously with the abundance of A-strategists with in vivo pathway but not the Y-strategists with ex vivo pathway. Overall, the result of this study shows a trade-off. In RFPM practice, the ex vivo microbial pathway is enhanced along with the abundance of A-strategists. This is not the case for the in vivo pathway and associated abundance of Y-strategists, which are closely associated with SOC. Our findings underlined the impact of rhizoplane microbial metabolic pathways on SOC status is key to agricultural practices in drylands such as RFPM, and advanced our understanding of how microbes affect the carbon cycling in dryland farming.

Reducing spatial resolution increased net primary productivity prediction of terrestrial ecosystems: A Random Forest approach.

Net primary production (NPP) is a pivotal component of the terrestrial carbon dynamic, as it directly contributes to the sequestration of atmospheric carbon by vegetation. However, significant variations and uncertainties persist in both the total amount and spatiotemporal patterns of terrestrial NPP, primarily stemming from discrepancies among datasets, modeling approaches, and spatial resolutions. In order to assess the influence of different spatial resolutions on global NPP, we employed a random forest (RF) model using a global observational dataset to predict NPP at 0.05°, 0.25°, and 0.5° resolutions. Our results showed that (1) the RF model performed satisfactorily with modeling efficiencies of 0.53-0.55 for the three respective resolutions; (2) NPP exhibited similar spatial patterns and interannual variation trends at different resolutions; (3) intriguingly, total global NPP varied greatly across different spatial resolutions, amounting 57.3 ± 3.07 for 0.05°, 61.46 ± 3.27 for 0.25°, and 66.5 ± 3.42 Pg C yr-1 for 0.5°. Such differences may be associated with the resolution transformation of the input variables when resampling from finer to coarser resolution, which significantly increased the spatial and temporal variation characteristics, particularly in regions within the southern hemisphere such as Africa, South America, and Australia. Therefore, our study introduces a new concept emphasizing the importance of selecting an appropriate spatial resolution when modeling carbon fluxes, with potential applications in establishing benchmarks for global biogeochemical models.