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1.
Bioresour Technol ; 400: 130689, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38599353

RESUMO

In recent years, manganese (Mn) has emerged as an accelerator for nitrogen metabolism. However, the bioactivity of manganese is limited by the restricted contact between microbes and manganese minerals in the solid phase and by the toxicity of manganese to microbes. To enhance the bioactivity of solid-phase manganese, biomineralized manganese oxide (MnOx) modified by Lactobacillus was introduced. Nitrogen removal performance have confirmed the effective role of biomineralized MnOx in accelerating the removal of total inorganic nitrogen (TIN). Metagenomic analysis has confirmed the enhancement of the nitrogen metabolic pathway and microbial extracellular electron transfer (MEET) in biomineralized MnOx treatment group (BIOA group). Additionally, the enrichment of manganese oxidation and denitrification genus indicates a coupling between nitrogen metabolism and manganese metabolism. One point of views is that biomineralized MnOx-mediated nitrogen transformation processes could serve as a substitute for traditional nitrogen removal processes.

2.
Bioorg Chem ; 146: 107330, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38579615

RESUMO

The increased de novo serine biosynthesis confers many advantages for tumorigenesis and metastasis. Phosphoglycerate dehydrogenase (PHGDH), a rate-limiting enzyme in serine biogenesis, exhibits hyperactivity across multiple tumors and emerges as a promising target for cancer treatment. Through screening our in-house compound library, we identified compound Stattic as a potent PHGDH inhibitor (IC50 = 1.98 ± 0.66 µM). Subsequent exploration in structural activity relationships led to the discovery of compound B12 that demonstrated the increased enzymatic inhibitory activity (IC50 = 0.29 ± 0.02 µM). Furthermore, B12 exhibited robust inhibitory effects on the proliferation of MDA-MB-468, NCI-H1975, HT1080 and PC9 cells that overexpress PHGDH. Additionally, using a [U-13C6]-glucose tracing assay, B12 was found to reduce the production of glucose-derived serine in MDA-MB-468 cells. Finally, mass spectrometry-based peptide profiling, mutagenesis experiment and molecular docking study collectively suggested that B12 formed a covalent bond with Cys421 of PHGDH.


Assuntos
Inibidores Enzimáticos , Fosfoglicerato Desidrogenase , Simulação de Acoplamento Molecular , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Serina , Glucose , Linhagem Celular Tumoral
3.
Phytomedicine ; 128: 155385, 2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38569292

RESUMO

BACKGROUND: Xianlian Jiedu Decoction (XLJDD) has been used for the treatment of colorectal cancer (CRC) for several decades because of the prominent efficacy of the prescription. Despite the clear clinical efficacy of XLJDD, the anti-CRC mechanism of action is still unclear. PURPOSE: The inhibitory effect and mechanism of XLJDD on CRC were investigated in the azoxymethane/dextran sulfate sodium (AOM/DSS)-induced mice. METHODS: The AOM/DSS-induced mice model was adopted to evaluate the efficacy after administering the different doses of XLJDD. The therapeutic effects of XLJDD in treating AOM/DSS-induced CRC were investigated through histopathology, immunofluorescence and ELISA analysis methods. In addition, metabolomics profile and 16S rRNA analysis were used to explore the effective mechanisms of XLJDD on CRC. RESULTS: The results stated that the XLJDD reduced the number of tumor growth on the inner wall of the colon and the colorectal weight/length ratio, and suppressed the disease activity index (DAI) score, meanwhile XLJDD also increased body weight, colorectal length, and overall survival rate. The treatment of XLJDD also exhibited the ability to lower the level of inflammatory cytokines in serum and reduce the expression levels of ß-catenin, COX-2, and iNOS protein in colorectal tissue. The findings suggested that XLJDD has anti-inflammatory properties and may provide relief for those suffering from inflammation-related conditions. Mechanistically, XLJDD improved gut microbiota dysbiosis and associated metabolic levels of short chain fatty acids (SCFAs), sphingolipid, and glycerophospholipid. This was achieved by reducing the abundance of Turicibacter, Clostridium_sensu_stricto_1, and the levels of sphinganine, LPCs, and PCs. Additionally, XLJDD increased the abundance of Enterorhabdus and Alistipes probiotics, as well as the content of butyric acid and isovaleric acid. CONCLUSION: The data presented in this article demonstrated that XLJDD can effectively inhibit the occurrence of colon inner wall tumors by reducing the level of inflammation and alleviating intestinal microbial flora imbalance and metabolic disorders. It provides a scientific basis for clinical prevention and treatment of CRC.

4.
BMC Psychol ; 12(1): 190, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38582933

RESUMO

BACKGROUND: Social anxiety has been shown to affect college students' academic performance. However, the role of social media addiction and academic engagement in this association is unclear. METHODS: A total 2661 college students completed a self-report questionnaire including Liebowitz Social Anxiety Scale, the Bergen Social Media Addiction Scale, the Utrecht Student Work Engagement Scale for Students, and the grade point average. Hayes' PROCESS macro for SPSS was employed to test the serial mediation effect. RESULTS: Results indicated that social anxiety was negatively related to academic performance, only academic engagement played a single mediating role in the relationship between social anxiety and academic performance, meanwhile social media addiction and academic engagement acted as serial mediators between social anxiety on academic performance. CONCLUSIONS: Social media addiction and academic engagement can explain the potential mechanisms of the association between social anxiety and academic performance, which have implications for devising intervention strategies to enhance the mental health and academic outcomes of college students.


Assuntos
Desempenho Acadêmico , Terapia de Aceitação e Compromisso , Humanos , Transtorno de Adição à Internet , Estudantes , Ansiedade
5.
J Hazard Mater ; 470: 134218, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38581878

RESUMO

The development of high-performance sensors for doxycycline (DOX) detection is necessary because its residue accumulation will cause serious harm to human health and the environment. Here, a novel tri-emission ratiometric fluorescence sensor was proposed by using "post-mixing" strategy of different emissions fluorescence molecularly imprinted polymers with salicylamide as dummy template (DMIPs). BSA was chosen as assistant functional monomer, and also acted as sensitizers for the aggregation-induced emission (AIE) effect of DOX. The blue-emitting carbon dots and the red-emitting CdTe quantum dots were separately introduced into DMIPs as the response signals. Upon DOX recognition within 2 min, blue and red fluorescence of the tri-emission DMIPs sensor were quenched while green fluorescence of DOX was enhanced, resulting in a wide range of color variations observed over bluish violet-rosered-light pink-orange-yellow-green with a detection limit of 0.061 µM. The sensor possessed highly selective recognition and was successfully applied to detect DOX in complicated real samples. Moreover, with the fluorescent color collection and data processing, the smartphone-assisted visual detection of the sensors showed satisfied sensitivity with low detection limit. This work provides great potential applications for rapid and visual detection of antibiotics in complex substrates.


Assuntos
Antibacterianos , Compostos de Cádmio , Doxiciclina , Impressão Molecular , Pontos Quânticos , Espectrometria de Fluorescência , Telúrio , Doxiciclina/análise , Doxiciclina/química , Pontos Quânticos/química , Telúrio/química , Antibacterianos/análise , Compostos de Cádmio/química , Limite de Detecção , Fluorescência , Carbono/química , Corantes Fluorescentes/química , Polímeros Molecularmente Impressos/química , Smartphone
6.
Sci Rep ; 14(1): 8307, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594404

RESUMO

Due to the antiquity and difficulty of excavation, the Terracotta Warriors have suffered varying degrees of damage. To restore the cultural relics to their original appearance, utilizing point clouds to repair damaged Terracotta Warriors has always been a hot topic in cultural relic protection. The output results of existing methods in point cloud completion often lack diversity. Probability-based models represented by Denoising Diffusion Probabilistic Models have recently achieved great success in the field of images and point clouds and can output a variety of results. However, one drawback of diffusion models is that too many samples result in slow generation speed. Toward this issue, we propose a new neural network for Terracotta Warriors fragments completion. During the reverse diffusion stage, we initially decrease the number of sampling steps to generate a coarse result. This preliminary outcome undergoes further refinement through a multi-scale refine network. Additionally, we introduce a novel approach called Partition Attention Sampling to enhance the representation capabilities of features. The effectiveness of the proposed model is validated in the experiments on the real Terracotta Warriors dataset and public dataset. The experimental results conclusively demonstrate that our model exhibits competitive performance in comparison to other existing models.

7.
Acad Radiol ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38637240

RESUMO

RATIONALE AND OBJECTIVES: To evaluate the performance of deep learning (DL) in predicting different breast cancer molecular subtypes using DCE-MRI from two institutes. MATERIALS AND METHODS: This retrospective study included 366 breast cancer patients from two institutes, divided into training (n = 292), validation (n = 49) and testing (n = 25) sets. We first transformed the public DCE-MRI appearance to ours to alleviate small-data-size and class-imbalance issues. Second, we developed a multi-branch convolutional-neural-network (MBCNN) to perform molecular subtype prediction. Third, we assessed the MBCNN with different regions of interest (ROIs) and fusion strategies, and compared it to previous DL models. Area under the curve (AUC) and accuracy (ACC) were used to assess different models. Delong-test was used for the comparison of different groups. RESULTS: MBCNN achieved the optimal performance under intermediate fusion and ROI size of 80 pixels with appearance transformation. It outperformed CNN and convolutional long-short-term-memory (CLSTM) in predicting luminal B, HER2-enriched and TN subtypes, but without demonstrating statistical significance except against CNN in TN subtypes, with testing AUCs of 0.8182 vs. [0.7208, 0.7922] (p=0.44, 0.80), 0.8500 vs. [0.7300, 0.8200] (p=0.36, 0.70) and 0.8900 vs. [0.7600, 0.8300] (p=0.03, 0.63), respectively. When predicting luminal A, MBCNN outperformed CNN with AUCs of 0.8571 vs. 0.7619 (p=0.08) without achieving statistical significance, and is comparable to CLSTM. For four-subtype prediction, MBCNN achieved an ACC of 0.64, better than CNN and CLSTM models with ACCs of 0.48 and 0.52, respectively. CONCLUSION: Developed DL model with the feature extraction and fusion of DCE-MRI from two institutes enabled preoperative prediction of breast cancer molecular subtypes with high diagnostic performance.

8.
Int Immunopharmacol ; 133: 112079, 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38615376

RESUMO

Porcine rotavirus (PoRV) poses a threat to the development of animal husbandry and human health, leading to substantial economic losses. VP6 protein is the most abundant component in virus particles and also the core structural protein of the virus. Firstly, this study developed an antibiotic-resistance-free, environmentally friendly expression vector, named asd-araC-PBAD-alr (AAPA). Then Recombinant Lactiplantibacillus plantarum (L. plantarum) strains induced by arabinose to express VP6 and VP6-pFc fusion proteins was constructed. Subsequently, This paper discovered that NC8/Δalr-pCXa-VP6-S and NC8/Δalr-pCXa-VP6-pFc-S could enhance host immunity and prevent rotavirus infection in neonatal mice and piglets. The novel recombinant L. plantarum strains constructed in this study can serve as oral vaccines to boost host immunity, offering a new strategy to prevent PoRV infection.

9.
Front Oncol ; 14: 1272209, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38529384

RESUMO

Composite lymphoma is an uncommon type of lymphoid malignancy, and those consisting of concurrent diffuse large B-cell lymphoma (DLBCL) and peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS) in the same organ are rare. Here, we report a case of a 75-year-old male patient admitted to our emergency department with intestinal obstruction presenting with abdominal pain and vomiting. He underwent partial resection of the small intestine under general anesthesia, and subsequent histopathology confirmed the mass to be composite DLBCL and PTCL-NOS. The patient received chemotherapy with a rituximab-based regimen and achieved complete remission (CR). However, the recurrent disease presented with obstruction again ten months after treatment. He refused a second surgery, but salvage treatment was not effective. The patient survived for 20 months after diagnosis. In addition, we did a literature review to understand the clinical features, pathology, treatment, and prognosis of this type of composite lymphoma.

10.
IEEE Trans Vis Comput Graph ; 30(5): 2173-2183, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38437129

RESUMO

Category-level pose tracking methods can continuously track the pose of objects without requiring any prior knowledge of the specific shape of the tracked instance. This makes them advantageous in augmented reality and virtual reality applications. The key challenge is how to train neural networks to accurately predict the poses of objects they have never seen before and exhibit strong generalization performance. We propose a novel category-level 6D pose tracking method Corr-Track, which is capable of accurately tracking objects belonging to the same category from depth video streams. Our approach utilizes direct soft correspondence constraints to train a neural network, which estimates bidirectional soft correspondences between sparsely sampled point clouds of objects in two frames. We first introduce a soft correspondence matrix for pose tracking tasks and establish effective constraints through direct spatial point-to-point correspondence representations in the sparse point cloud correspondence matrix. We propose the "point cloud expansion" strategy to address the "point cloud shrinkage" problem resulting from soft correspondences. This strategy ensures that the corresponding point cloud accurately reproduces the shape of the target point cloud, leading to precise pose tracking results. We evaluated our approach on the NOCS-REAL275 and Wild6D dataset and observed superior performance compared to previous methods. Additionally, we conducted cross-category experiments that further demonstrated its generalization capability.

11.
Microbiol Spectr ; 12(4): e0347723, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38456681

RESUMO

Canine distemper virus (CDV) poses a severe threat to both domesticated and wild animals, including multiple carnivores. With the continued expansion of its host range, there is an urgent need for the development of a safer and more effective vaccine. In this study, we developed subunit vaccines based on a bacterium-like particle (BLP) delivery platform containing BLPs-F and BLPs-H, which display the CDV F and H glycoprotein antigens, respectively, using the antigen-protein anchor fusions produced by a recombinant baculovirus insect cell expression system. The combination of BLPs-F and BLPs-H (CDV-BLPs), formulated with colloidal manganese salt [Mn jelly (MnJ)] adjuvant, triggered robust CDV-specific antibody responses and a substantial increase in the number of interferon gamma (IFN-γ)-secreting CD4+ and CD8+ T cells in mice. Dogs immunized intramuscularly with this vaccine not only produced CDV-specific IgG but also displayed elevated concentrations of IFN-γ and interleukin 6 in their serum, along with an increase of the CD3+CD4+ and CD3+CD8+ T cell subsets. Consequently, this heightened immune response provided effective protection against disease development and reduced viral shedding levels following challenge with a virulent strain. These findings suggest that this BLP-based subunit vaccine has the potential to become a novel canine distemper vaccine. IMPORTANCE: Many sensitive species require a safe and effective distemper vaccine. Non-replicating vaccines are preferred. We constructed subunit particles displaying canine distemper virus (CDV) antigens based on a bacterium-like particle (BLP) delivery platform. The CDV-BLPs formulated with theMn jelly adjuvant induced robust humoral and cell-mediated immune responses to CDV in mice and dogs, thereby providing effective protection against a virulent virus challenge. This work is an important step in developing a CDV subunit vaccine.


Assuntos
Vírus da Cinomose Canina , Vacinas Virais , Cães , Animais , Camundongos , Vírus da Cinomose Canina/genética , Vacinas Virais/genética , Linfócitos T CD8-Positivos , Anticorpos Antivirais , Proteínas Recombinantes , Vacinas de Subunidades/genética
13.
Pharmaceuticals (Basel) ; 17(3)2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38543173

RESUMO

Tumor cell stemness stands out as a pivotal factor driving tumor recurrence or metastasis and significantly contributes to the mortality of patients with colorectal cancer (CRC). Recent research has unveiled a link between immune-active cells and the induction of tumor cell stemness, ultimately leading to heightened resistance to treatment. In this study, stemness in CRC cell lines was assessed after co-culture with natural killer (NK) cells, both with and without sulfarotene administration. Furthermore, a CRC xenograft model was utilized to scrutinize the in vivo efficacy of sulfarotene in overcoming stemness induced by NK cell activation. As a result, CRC cells exhibited significant stemness after NK cell co-culture, as evidenced by the upregulation of several stemness markers associated with cancer stem cells. Moreover, these cells demonstrated remarkable resistance to commonly used chemotherapy agents for CRC, such as oxaliplatin and irinotecan. Importantly, sulfarotene effectively reversed the altered stemness of CRC cells in both in vitro and in vivo assays. In conclusion, sulfarotene emerges as a promising therapeutic strategy for overcoming colorectal cancer resistance to NK cells by effectively inhibiting stemness remodeling. This study underscores the potential of sulfarotene in augmenting NK-cell-mediated immune surveillance, proposing a novel immunotherapeutic approach against colorectal cancer.

14.
Chemistry ; : e202400261, 2024 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-38433578

RESUMO

90 Sr, as a typical artificial radionuclide, poses a serious threat to human health and the ecological environment. The selective removal of this radionuclide from industrial nuclear waste is crucial for our environment. Here we report a novel potassium fluoroaluminate, K2 [(AlF5 )H2 O], which was synthesized by a simple low-temperature one-step method. It adopts a 1D AlF6 -chain structure, which consists of exchangeable potassium ions in between the infinite chains of octahedral Al centers. As a remarkable inorganic ionic exchanger, K2 [(AlF5 )H2 O] has a high chemical stability (resistance of pH=~3-12) and thermal stability (≥~300 °C). It possesses an excellent adsorption selectivity (Kd =~6.1×104  mL ⋅ g-1 ) and a maximum adsorption capacity of qm =~120.32 mg ⋅ g-1 for Sr2+ . Importantly, it still keep a very good selectivity for Sr2+ ions even in the presence of competing Na+ , Mg2+ and Ca2+ aqueous solutions. K2 [(AlF5 )H2 O] is the first example of fluoroaluminate ionic exchange materials that can capture Sr2+ . This result opens up a new way to design and synthesize inorganic ionic exchangers for the selective removal of Sr2+ ions from radioactive waste water.

15.
Ann Hematol ; 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38448788

RESUMO

Waldenström macroglobulinemia (WM) is a type of B-cell lymphoma that produces IgM. Our study aimed to investigate the role of CXCL13, a chemokine essential for B lymphocytes, in the evaluation of treatment response and prognosis in WM. We collected serum samples and clinical data from 72 WM patients, with 69 patients receiving systemic therapy and 3 patients opting not to receive treatment. Serum CXCL13 levels at baseline and after six months of treatments were measured by enzyme-linked immunosorbent assay. The median serum level of CXCL13 was 1 539.2 pg/ml (range 10.0-21 389.9) at baseline and significantly decreased to 123.1 pg/ml (range 0.0-6 741.5) after 6 months of treatments. At baseline, higher CXCL13 levels were associated with lower hemoglobin levels (p = 0.001), higher ß2-microglobulin levels (p = 0.001), lower albumin levels (p = 0.046), and higher IPSS-WM scores (p = 0.013). After 6 months of treatment, patients who achieved PR/VGPR had significantly lower CXCL13 levels compared to those with SD (70.2 pg/ml vs 798.6 pg/ml, p = 0.002). The median follow-up period was 40 months (range 4.2-188). Eight patients died during the follow-up period. Overall survival differed based on CXCL13 levels. When grouped by baseline CXCL13 levels, the median OS was 60.0 months in patients with serum CXCL13 > 2 000 pg/ml, while it was not reached in patients with low CXCL13 levels (p < 0.001). Based on CXCL13 levels after the treatments, the median OS was 74.0 months in patients with serum CXCL13 > 200 pg/ml, while it was not reached in patients with CXCL13 ≤ 200 pg/ml. In a subgroup of 28 patients with a series of serum samples, the increase of serum CXCL13 level was associated with disease progression or the start of next-line therapy (p < 0.001). Our study concludes that serum CXCL13 levels decrease in WM patients treated with various regimens and correlate with treatment response. Detecting serum CXCL13 at baseline or after treatment help in predicting prognosis.

17.
Dig Dis Sci ; 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38483780

RESUMO

OBJECTIVE: To investigate the safety and prognosis of enbloc or piecemeal removal after enbloc resection of a gastric GIST by comparing the clinical data of endoscopic en block resection and piecemeal removal (EP) and en block resection and complete removal (EC) of gastric GISTs. METHODS: A total of 111 (43 endoscopic piecemeal, and 68 complete removal) patients with gastric GIST's ≥ 2 cm in diameter who underwent endoscopic therapy from January 2016 to June 2020 at the First Affiliated Hospital of Zhengzhou University were retrospectively analyzed. In all cases, it was ensured that the tumor was intact during the resection, however, it was divided into EP group and EC group based on whether the tumor was completely removed or was cut into pieces which were then removed. The patients' recurrence-free survival rate and recurrence-free survival (RFS) were recorded. RESULTS: There was no statistically significant difference in RFS rates between the two groups (P = 0.197). The EP group had relatively high patient age, tumor diameter, risk classification, and operation time. However, there was no statistically significant difference in the number of nuclear fission images, postoperative hospitalization time, postoperative fasting time, complication rate and complication grading between the two groups (P > 0.05). CONCLUSION: Endoscopic piecemeal removal after en block resection of gastric GIST is safe and effective and achieves similar clinical outcomes as complete removal after en block resection.

18.
Materials (Basel) ; 17(5)2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38473571

RESUMO

This study investigates the influence of varying austenitizing temperatures on the microstructure and mechanical properties of 35Si2MnCr2Ni3MoV steel, utilizing Charpy impact testing and microscopic analysis techniques such as scanning electron microscopy (SEM) and electron backscatter diffraction (EBSD). The findings reveal that optimal combination of strength and toughness is achieved at an austenitizing temperature of 980 °C, resulting in an impact toughness of 67.2 J and a tensile strength of 2032 MPa. The prior austenite grain size initially decreases slightly with increasing temperature, then enlarges significantly beyond 1100 °C. The martensite blocks' and packets' structures exhibit a similar trend. The proportion of high-angle grain boundaries, determined by the density of the packets, peaks at 980 °C, providing maximal resistance to crack propagation. The amount of retained austenite increases noticeably after 980 °C; beyond 1200 °C, the coarsening of packets and a decrease in density reduce the likelihood of trapping retained austenite. Across different austenitizing temperatures, the steel demonstrates superior crack initiation resistance compared to crack propagation resistance, with the fracture mode transitioning from ductile dimple fracture to quasi-cleavage fracture as the austenitizing temperature increases.

19.
Materials (Basel) ; 17(4)2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38399118

RESUMO

This study aims to investigate in situ the three-dimensional (3D) morphology and distribution of primary carbides (PCs) in electro-slag remelting (ESR) forged 30Cr3Ni3Mo2V steel. A facile non-aqueous electrolytic etching method was applied to prepare 3D PCs on the matrix. The morphology, composition, and element concentrations of PCs were characterized using a combination of optical microscopy (OM), scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS), and electron back-scattered diffusion (EBSD). The precipitation, type, and composition of PCs in the same steel were also simulated using Thermo-Calc software Version 2015a. The results indicate that PC is rich in Nb, which is a potential heterogeneous nucleating agent. Both the size and number of PCs increase from the edge to the center of the ingot. The large-sized PCs present three dominant types of morphology, which vary in different regions, i.e., a bulky type dominates in the edge region, a lamellar type dominates in the middle region, and a stripy type dominates in the core region. The results of EBSD analysis show that the orientation of PCs with different morphologies is different and that more nanosized V-rich type carbides are precipitated on the matrix. The thermodynamic calculations show that MC precipitates from the liquid phase when the solid phase fraction is greater than 0.985 and that the MC-type carbides are rich in Nb, which agrees well with the experimental results.

20.
Sci Total Environ ; 919: 170897, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38346659

RESUMO

The potential increases in carbon stocks in arid regions due to recent shrub encroachment have attracted extensive interest among both ecologists and carbon policy analysts. Quantifying the shrub root biomass amount in these ecosystems is essential to understanding the ecological changes occurring. In this paper, we proposed a simple nondestructive method for estimating the coarse lateral root biomass of shrubs based on the root counts obtained from ground-penetrating radar (GPR) radargrams. Root data were gathered via field experiments using GPR with antenna center frequencies of 900 MHz and 400 MHz. Five Caragana microphylla Lam. shrubs of different sizes were selected for measuring objects, and a total of 40 GPR survey lines were established for GPR data acquisition. The soil profile wall excavation method was used to obtain the total root biomass from each radargram. A model for estimating the root biomass was built by establishing the relationship between the root biomass in each profile and the root counts interpreted from the radargrams. According to the mathematical relationship between the root diameter and root biomass, the proxy root radius was derived, which could explain the rationality of the proposed model from the biological mechanism. The established model provided high confidence in estimating the root dry biomass using the GPR data obtained at the two antenna frequencies (R2= 0.73 for 900 MHz and R2= 0.71 for 400 MHz). The leave-one-out cross-validation results showed that the model exhibits satisfactory performance. This study expands the application of geophysical methods in root research and offers a new simplified method for estimating the root biomass from GPR data under field conditions.


Assuntos
Caragana , Ecossistema , Biomassa , Radar , China , Carbono
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