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1.
Phys Chem Chem Phys ; 26(4): 3110-3116, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38189422

RESUMO

Based on first-principles calculations, we predict a class of graphene-like magnetic materials, transition metal carbonitrides MN4C6 (M = Cr, Mn, Fe, and Co), which are made up of a benzene ring and an MN4 moiety, two common planar units in the compounds. The structural stability is demonstrated by the phonon and molecular dynamics calculations, and the formation mechanism of the planar geometry of MN4C6 is ascribed to the synergistic effect of sp2 hybridization, M-N coordination bond, and π-d conjugation. The MN4C6 materials consist of only one layer of atoms and the transition metal atom is located in the planar crystal field, which is markedly different from most two-dimensional materials. The calculations indicate that MnN4C6, FeN4C6, and CoN4C6 are ferromagnetic while CrN4C6 has an antiferromagnetic ground state. The Curie temperatures are estimated by solving the anisotropic Heisenberg model with the Monte Carlo method.

2.
Molecules ; 29(10)2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38792183

RESUMO

Two-dimensional intrinsic magnetic materials with high Curie temperature are promising candidates for next-generation spintronic devices. In this work, we design two kinds of two-dimensional transition metal nitrides, VN2 and FeN2, both with a hexagonal honeycomb lattice. Based on the formation energy, and phonon spectra calculations as well as the molecular dynamics simulations, their structural stability is demonstrated. Then, we determine the ferromagnetic ground states of VN2 and FeN2 monolayers through the energy calculations, and the Curie temperatures of 222 K and 238 K are estimated by solving the Heisenberg model using the Monte Carlo simulation method. Hence, the VN2 and FeN2 monolayers are demonstrated to be new two-dimensional ferromagnetic materials with high temperature ferromagnetism or large-gap half-metallicity.

3.
Cancer Cell Int ; 23(1): 245, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37853482

RESUMO

GAS41, a member of the human YEATS domain family, plays a pivotal role in human cancer development. It serves as a highly promising epigenetic reader, facilitating precise regulation of cell growth and development by recognizing essential histone modifications, including histone acetylation, benzoylation, succinylation, and crotonylation. Functional readouts of these histone modifications often coincide with cancer progression. In addition, GAS41 functions as a novel oncogene, participating in numerous signaling pathways. Here, we summarize the epigenetic functions of GAS41 and its role in the carcinoma progression. Moving forward, elucidating the downstream target oncogenes regulated by GAS41 and the developing small molecule inhibitors based on the distinctive YEATS recognition properties will be pivotal in advancing this research field.

4.
Artigo em Inglês | MEDLINE | ID: mdl-37103464

RESUMO

Four Gram-negative bacterial strains isolated from Steinernema africanum entomopathogenic nematodes were biochemically and molecularly characterized to determine their taxonomic position. Results of 16S rRNA gene sequencing indicated that they belong to the class Gammaproteobacteria, family Morganellaceae, genus Xenorhabdus, and that they are conspecific. The average 16S rRNA gene sequence similarity between the newly isolated strains and the type strain of its more closely related species, Xenorhabdus bovienii T228T, is 99.4 %. We therefore selected only one of them, XENO-1T, for further molecular characterization using whole genome-based phylogenetic reconstructions and sequence comparisons. Phylogenetic reconstructions show that XENO-1T is closely related to the type strain of X. bovienii, T228T, and to several other strains that are thought to belong to this species. To clarify their taxonomic identities, we calculated average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values. We observed that the ANI and dDDH values between XENO-1T and X. bovienii T228T are 96.3 and 71.2 %, respectively, suggesting that XENO-1T represents a novel subspecies within the X. bovienii species. Noteworthy, the dDDH values between XENO-1T and several other X. bovienii strains are between 68.7 and 70.9 % and ANI values are between 95.8 and 96.4 %, which could be interpreted, in some instances, as that XENO-1T represents a new species. Considering that for taxonomic description the genomic sequences of the type strains are compared, and to avoid future taxonomic conflicts, we therefore propose to assign XENO-1T to a new subspecies within X. bovienii. ANI and dDDH values between XENO-1T and any other of the species with validly published names of the genus are lower than 96 and 70 %, respectively, supporting its novel status. Biochemical tests and in silico genomic comparisons show that XENO-1T exhibit a unique physiological profile that differs from all the Xenorhabdus species with validly published names and from their more closely related taxa. Based on this, we propose that strain XENO-1T represents a new subspecies within the X. bovienii species, for which we propose the name X. bovienii subsp. africana subsp. nov, with XENO-1T (=CCM 9244T=CCOS 2015T) as the type strain.


Assuntos
Rabditídios , Xenorhabdus , Animais , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Composição de Bases , Ácidos Graxos/química , Rabditídios/genética , Rabditídios/microbiologia , Hibridização de Ácido Nucleico , Nucleotídeos
5.
Phys Chem Chem Phys ; 25(30): 20189-20193, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37489584

RESUMO

Transition metal single-atom catalysts have attracted great attention because of their great potential applications in the chemical industry. Except for graphene, there are few single-layer materials that can act as substrates to support the dispersive metal atoms. Recently, a biphenylene layer, a new two-dimensional allotrope of graphene, was synthesized in experiments, providing a new substrate layer to fabricate single-atom catalysts (SACs). In this work, we predict three transition metal SACs MN4-biphenylene (M = Fe, Co, and Ni) based on first-principles calculations. The results indicate that FeN4-biphenylene is a promising bifunctional catalyst with low overpotentials for both the oxygen reduction reaction and oxygen evolution reaction, ηORR = 0.11 V and ηOER = 0.27 V. The high catalytic activities are explained by the position of the d-band center of the Fe atom in the biphenylene network and the strength of interaction between FeN4-biphenylene and the reaction intermediates.

6.
Pestic Biochem Physiol ; 196: 105621, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37945257

RESUMO

Biocontrol of subterranean termites is largely impeded by their social immune responses. Studies on biocontrol agents combined with natural insecticides and their possible effects on the immune defense mechanisms of termites are limited. In this study, we investigated the effects of a combined biocontrol strategy using a plant-derived insect ATPase inhibitor, α-terpineol, with the entomopathogenic nematodes (EPNs) Steinernema carpocapsae against the subterranean termite Coptotermes formosanus Shiraki. Survival assays showed that even a low lethal concentration of α-terpineol significantly increased the EPNs-induced virulence in C. formosanus. α-terpineol treatment majorly inhibited the activity of Na+- K+- ATPase, which disturbed the EPNs-induced enhancement of locomotor activity and grooming behavior in termites treated with the combined strategy. Furthermore, the combination treatment had a synergistic inhibitory effect on innate immune responses in C. formosanus, which were measured as changes in the expression of immune-related genes and activities of immune system enzymes. In conclusion, α-terpineol can weaken the immune defense of termites against EPNs at low lethal concentrations, and is a suitable non-synthetic insecticide to prove the biocontrol efficiency of EPNs on C. formosanus. This study provides a theoretical basis and technical reference for a novel biocontrol strategy that promises to overcome the problems of host immune defense in termites.


Assuntos
Inseticidas , Isópteros , Nematoides , Animais , Isópteros/fisiologia , Virulência , Inseticidas/farmacologia , Adenosina Trifosfatases
7.
Plant Dis ; 107(8): 2325-2334, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37596715

RESUMO

Banana (Musa spp.) is an important fruit and food crop worldwide. In recent years, banana sheath rot has become a major problem in banana cultivation, causing plant death and substantial economic losses. Nevertheless, the pathogen profile of this disease has not been fully characterized. Klebsiella variicola is a versatile bacterium capable of colonizing different hosts, such as plants, humans, insects, and animals, and is recognized as an emerging pathogen in various hosts. In this study, we obtained 12 bacterial isolates from 12 different banana samples showing banana sheath rot in Guangdong and Guangxi Provinces, China. Phylogenetic analysis based on 16S rRNA sequences confirmed that all 12 isolates were K. variicola strains. We sequenced the genomes of these strains, performed comparative genomic analysis with other sequenced K. variicola strains, and found a lack of consistency in accessory gene content among these K. variicola strains. However, prediction based on the pan-genome of K. variicola revealed 22 unique virulence factors carried by the 12 pathogenic K. variicola isolates. Microbiome and microbial interaction network analysis of endophytes between the healthy tissues of diseased plants and healthy plants of two cultivars showed that Methanobacterium negatively interacts with Klebsiella in banana plants and that Herbaspirillum might indirectly inhibit Methanobacterium to promote Klebsiella growth. These results suggest that banana sheath rot is caused by the imbalance of plant endophytes and opportunistic pathogenic bacteria, providing an important basis for research and control of this disease.[Formula: see text] Copyright © 2023 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.


Assuntos
Musa , Animais , Humanos , Filogenia , RNA Ribossômico 16S/genética , China , Klebsiella/genética , Endófitos
8.
J Nematol ; 54(1): 20220049, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36457370

RESUMO

Alternatives to hazardous insecticides are urgently needed for an environmentally friendly and effective management of insect pests. One such option is the use of entomopathogenic nematodes (EPN). To increase the availability of EPN with potential for biocontrol, we surveyed agricultural soils in the Republic of Rwanda and collected two Steinernema isolates. Initial molecular characterization showed that they represent a new species, for which we propose the name S. africanum n. sp. To describe this new species, we reconstructed phylogenetic relationships, calculated sequence similarity scores, characterized the nematodes at the morphological level, conducted crossing experiments, and isolated and characterized their symbiotic bacteria. At the molecular level, S. africanum n. sp. is closely related to S. litorale and S. weiseri. At the morphological level, S. africanum n. sp. differs from closely related species by the position of the nerve ring and also because the stoma and pharynx region is longer. The first-generation males have ventrally curved spicules with lanceolate manubrium and fusiform gubernaculum and the second-generation males have rounded manubrium and anteriorly hook-like gubernaculum. Steinernema africanum n. sp. does not mate or produce fertile progeny with any of the closely related species.

9.
J Chem Phys ; 150(7): 074306, 2019 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-30795678

RESUMO

To clarify the charge transfer effect on Raman spectra of aromatic hydrocarbons, we investigate the Raman shifts of phenanthrene, p-terphenyl, and anthracene and their negatively charged counterparts by using density functional theory. For the three molecules, upon charge increasing, the computed Raman peaks generally shift down with the exception of a few shifting up. The characteristic Raman modes in the 0-1000 cm-1 region persist up, while some high-frequency ones change dramatically with three charges transferred. The calculated Raman shifts for one- and two-electron transfer are in agreement with the measured Raman spectra, and in accordance to the stoichiometric ratios 1:1 and 2:1 of the metal atom and aromatic hydrocarbon molecule in recent experimental and theoretical studies. Our theoretical results provide the fundamental information to elucidate the Raman shifts and the stoichiometric ratios for alkali-metal-doped aromatic hydrocarbons.

10.
J Biol Chem ; 291(36): 18856-66, 2016 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-27417137

RESUMO

Long term synaptic plasticity, such as long term potentiation (LTP), has been widely accepted as a cellular mechanism underlying memory. Recently, it has been unraveled that Shp2 plays a role in synaptic plasticity and memory in Drosophila and mice, revealing significant and conserved effects of Shp2 in cognitive function. However, the exact mechanism underlying this function of Shp2 in synaptic plasticity and memory still remains elusive. Here, we examine the regulation of Shp2 in hippocampal LTP and contextual fear conditioning. We find that Shp2 is rapidly recruited into spines after LTP induction. Furthermore, the phosphorylation level of Shp2 at Tyr-542 is elevated after LTP stimuli either in cultured hippocampal neurons or acute slices. Notably, contextual fear conditioning also regulates the phosphorylation level of Shp2 at Tyr-542, suggesting fine-tuned regulation of Shp2 in LTP and memory formation. By using a Shp2-specific inhibitor and adeno-associated virus-Cre mediated Shp2 knock-out in cultured neurons, we provide evidence that the phosphatase activity of Shp2 is critical for activity-dependent AMPA receptor surface trafficking. Collectively, our results have revealed a regulatory mechanism of Shp2 underlying LTP and memory, broadening our understanding of Shp2 in cognitive function.


Assuntos
Hipocampo/fisiologia , Potenciação de Longa Duração/fisiologia , Memória/fisiologia , Neurônios/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Receptores de AMPA/metabolismo , Animais , Cognição/fisiologia , Drosophila melanogaster , Técnicas de Silenciamento de Genes , Hipocampo/citologia , Camundongos , Neurônios/citologia , Transporte Proteico/fisiologia , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética , Ratos , Ratos Sprague-Dawley , Receptores de AMPA/genética
11.
Appl Microbiol Biotechnol ; 100(1): 299-310, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26433967

RESUMO

Uranium tailing is a serious pollution challenge for the environment. Based on metagenomic sequencing analysis, we explored the functional and structural diversity of the microbial community in six soil samples taken at different soil depths from uranium-contaminated and uncontaminated areas. Kyoto Encyclopedia of Genes and Genomes Orthology (KO) groups were obtained using a Basic Local Alignment Search Tool search based on the universal protein resource database. The KO-pathway network was then constructed using the selected KOs. Finally, alpha and beta diversity analyses were performed to explore the differences in soil bacterial diversity between the radioactive soil and uncontaminated soil. In total, 30-68 million high-quality reads were obtained. Sequence assembly yielded 286,615 contigs; and these contigs mostly annotated to 1699 KOs. The KO distributions were similar among the six soil samples. Moreover, the proportion of the metabolism of other amino acids (e.g., beta-alanine, taurine, and hypotaurine) and signal transduction was significantly lower in radioactive soil than in uncontaminated soil, whereas the proportion of membrane transport and carbohydrate metabolism was higher. Additionally, KOs were mostly enriched in ATP-binding cassette transporters and two-component systems. According to diversity analyses, Actinobacteria and Proteobacteria were the dominant phyla in radioactive and uncontaminated soil, and Robiginitalea, Microlunatus, and Alicyclobacillus were the dominant genera in radioactive soil. Taken together, these results demonstrate that soil microbial community, structure, and functions show significant changes in uranium-contaminated soil. The dominant categories such as Actinobacteria and Proteobacteria may be applied in environmental governance for uranium-contaminated soil in southern China.


Assuntos
Bactérias/classificação , Bactérias/metabolismo , Biota , Metagenoma , Microbiologia do Solo , Poluentes do Solo/metabolismo , Urânio/metabolismo , Bactérias/genética , China , Metagenômica
12.
Int J Mol Sci ; 16(6): 11849-63, 2015 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-26016497

RESUMO

Several studies have examined the associations of methylenetetrahydrofolate reductase (MTHFR) C677T and methionine synthase reductase (MTRR) A66G polymorphisms with being overweight/obesity. However, the results are still controversial. We therefore conducted a case-control study (517 cases and 741 controls) in a Chinese Han population and then performed a meta-analysis by combining previous studies (5431 cases and 24,896 controls). In our case-control study, the MTHFR C677T polymorphism was not significantly associated with being overweight/obesity when examining homozygous codominant, heterozygous codominant, dominant, recessive and allelic genetic models. The following meta-analysis confirmed our case-control results. Heterogeneity was minimal in the overall analysis, and sensitivity analyses and publication bias tests indicated that the meta-analytic results were reliable. Similarly, both the case-control study and meta-analysis found no significant association between the MTRR A66G polymorphism and being overweight/obesity. However, sensitivity analyses showed that the associations between the MTRR A66G polymorphism and being overweight/obesity became significant in the dominant, heterozygous codominant and allelic models after excluding our case-control study. The results from our case-control study and meta-analysis suggest that both of the two polymorphisms are not associated with being overweight/obesity. Further large-scale population-based studies, especially for the MTRR A66G polymorphism, are still needed to confirm or refute our findings.


Assuntos
Povo Asiático/genética , Ferredoxina-NADP Redutase/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Obesidade/genética , Sobrepeso/genética , Polimorfismo de Nucleotídeo Único , Adulto , Estudos de Casos e Controles , China , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade
13.
J Chem Phys ; 141(22): 224501, 2014 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-25494754

RESUMO

We have systematically investigated the crystal structure of Ba-doped phenanthrene with various Ba doping levels by the first-principles calculations combined with the X-ray diffraction (XRD) spectra simulations. Although the experimental stoichiometry ratio of Ba atom and phenanthrene molecule is 1.5:1, the simulated XRD spectra, space group symmetry and optimized lattice parameters of Ba1.5phenanthrene are not consistent with the experimental ones, while the results for Ba2phenanthrene are in good agreement with the measurements. The strength difference of a few XRD peaks can be explained by the existence of pristine phenanthrene. Our findings suggest that instead of uniform Ba1.5phenanthrene, there coexist Ba2phenanthrene and undoped phenanthrene in the superconducting sample. The electronic calculations indicate that Ba2phenanthrene is a semiconductor with a small energy gap less than 0.05 eV.

14.
BMC Pulm Med ; 14: 87, 2014 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-24886114

RESUMO

BACKGROUND: Whole-lung lavage (WLL) is classically the first-line treatment for symptomatic pulmonary alveolar proteinosis (PAP). However, some patients require multiple WLLs because of refractory nature of their PAP. In this instance, these patients may benefit from new treatment regimens, and new therapies should be tried for these patients. CASE PRESENTATION: We describe a 47-year-old Chinese woman who was confidently diagnosed with pulmonary alveolar proteinosis (PAP) after bronchoalveolar lavage and transbronchial lung biopsy. The patient received four sessions of bilateral whole lung lavage (WLL) and one session of WLL in combination with plasmapheresis, each only producing short-term symptomatic relief. The patient was given a trial of combination therapy, which consisted of WLL and Granulocyte-macrophage colony-stimulating factor (GM-CSF) inhalation. The patient showed a gradual improvement in oxygenation and her daily activity, as well as a dramatic improvement in her pulmonary CT examination. CONCLUSION: Bilateral WLL, in combination with GM-CSF inhalation, may be an effective treatment option for severe refractory PAP.


Assuntos
Lavagem Broncoalveolar/métodos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/uso terapêutico , Proteinose Alveolar Pulmonar/diagnóstico por imagem , Proteinose Alveolar Pulmonar/terapia , Administração por Inalação , Terapia Combinada , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Proteinose Alveolar Pulmonar/fisiopatologia , Medição de Risco , Índice de Gravidade de Doença , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento
15.
BMC Pulm Med ; 14: 8, 2014 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-24468083

RESUMO

BACKGROUND: Pulmonary involvement is a common feature of MPA. Although alveolar hemorrhage is the most common pulmonary manifestation of MPA, a few recent studies have described instances of MPA patients with pulmonary fibrosis. Pulmonary fibrosis was seen to predate, be concomitant with, or occur after the diagnosis of MPA. The goal of this study was to describe the clinical features and prognosis of microscopic polyangiitis (MPA) patients whose initial respiratory presentation was pulmonary fibrosis. METHODS: We conducted a retrospective analysis of 19 MPA patients who presented with pulmonary fibrosis at Peking Union Medical College Hospital between 1990 and 2012. RESULTS: Of 67 total MPA cases, 19 patients presented with pulmonary fibrosis. There were 8 males and 11 females, with a median age of 63.6 years. Common clinical manifestations included fever (89.5%), cough (84.2%), dyspnea (78.9%) and velcro rales (84.2%). Eleven patients experienced weight loss, several had kidney involvement, and most had an increased erythrocyte sedimentation rate and C-reactive protein. All were positive for myeloperoxidase-anti-neutrophil cytoplasmic antibody (ANCA), with 6 patients being positive at the time of their initial diagnosis of pulmonary fibrosis. Every patient had typical features of usual interstitial pneumonia on High-resolution CT. All were treated with corticosteroids and cyclophosphamide, which lead to an improvement in twelve cases. One of the remaining patients progressed slowly, whereas six died. CONCLUSIONS: Patients with MPA, who also presented with pulmonary fibrosis in our cohort, were more likely to be older, female, and have extrapulmonic involvement. Most patients had a delayed positive ANCA. Corticosteroids plus cyclophosphamide was the remission-induction treatment scheme for all cases. The current prognosis for MPA patients with pulmonary fibrosis appears to be poor, suggesting that they may be candidates for new therapies.


Assuntos
Poliangiite Microscópica/complicações , Poliangiite Microscópica/diagnóstico , Fibrose Pulmonar/etiologia , Adulto , Idoso , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos
16.
Insect Sci ; 2024 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-38494587

RESUMO

Using synthetic microbial communities to promote host growth is an effective approach. However, the construction of such communities lacks theoretical guidance. Kin discrimination is an effective means by which strains can recognize themselves from non-self, and construct competitive microbial communities to produce more secondary metabolites. However, the construction of cooperative communities benefits from the widespread use of beneficial microorganisms. We used kin discrimination to construct synthetic communities (SCs) comprising 13 Bacillus subtilis strains from the surface and gut of black soldier fly (BSF) larvae. We assessed larval growth promotion in a pigeon manure system and found that the synthetic community comprising 4 strains (SC 4) had the most profound effect. Genomic analyses of these 4 strains revealed that their complementary functional genes underpinned the robust functionality of the cooperative synthetic community, highlighting the importance of strain diversity. After analyzing the bacterial composition of BSF larvae and the pigeon manure substrate, we observed that SC 4 altered the bacterial abundance in both the larval gut and pigeon manure. This also influenced microbial metabolic functions and co-occurrence network complexity. Kin discrimination facilitates the rapid construction of synthetic communities. The positive effects of SC 4 on larval weight gain resulted from the functional redundancy and complementarity among the strains. Furthermore, SC 4 may enhance larval growth by inducing shifts in the bacterial composition of the larval gut and pigeon manure. This elucidated how the SC promoted larval growth by regulating bacterial composition and provided theoretical guidance for the construction of SCs.

17.
Huan Jing Ke Xue ; 45(1): 508-519, 2024 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-38216500

RESUMO

Exploring the effects of artificial Haloxylon ammodendron forest planting on the structure and function of a desert soil bacterial community provides data reference for soil micro-ecological restoration and land quality improvement in desert oasis transition zones. Illumina high-throughput sequencing technology and PICRUSt2 functional prediction analysis were used to identify and analyze the structure and function of soil bacterial communities, and the Mantel correlation test and RDA analysis were used to explain the physicochemical factors affecting the structure and function of soil bacterial communities. The results showed that:① the soil bacterial OTU number, Chao1 index, and Shannon index were significantly higher in the H. ammodendron forest than in the mobile dune soil, and the PCoA analysis and Adonis test showed significant differences in the soil bacterial community structure between H. ammodendron and mobile dune soil (P=0.001). ② A total of 34 phyla, 89 classes, 174 orders, 262 families, and 432 genera of bacteria were detected in all samples, and the phyla Proteobacteria, Actinobacteria, Cyanobacteria, and Chloroflexi accounted for 76.05% of the relative abundance of soil bacteria, which belonged to the dominant soil bacteria, among which the relative abundance of Actinobacteria in H. ammodendron forest soil was extremely significantly higher than that in mobile dune soil (P < 0.01). ③PICRUSt2 function prediction revealed that the soil bacterial community of H. ammodendron forest included six categories of primary functions and 28 categories of secondary functions, among which the metabolism of carbohydrates, metabolism of amino acids, and metabolism of cofactors and vitamins were all greater than 10% in relative abundance and were the main metabolic functions of H. ammodendron forest soil bacteria. ④ The planting of H. ammodendron forest significantly improved the nutrient content of soil organic matter and other nutrients. Soil pH, organic matter, total nitrogen, and fast-acting phosphorus were the main physicochemical factors affecting the bacterial community, with soil organic matter significantly affecting the soil bacterial community structure (P < 0.05) and metabolic function (P < 0.05). In conclusion, the artificial H. ammodendron forest helped to increase desert soil microbial diversity, increase the relative abundance of soil bacterial metabolic function genes, and improve the desert soil microenvironment.


Assuntos
Chenopodiaceae , Solo , Humanos , Florestas , Bactérias/genética , Genes Bacterianos , Microbiologia do Solo
18.
Environ Sci Pollut Res Int ; 31(30): 42970-42990, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38886269

RESUMO

Air pollution can cause disease and has become a major global environmental problem. It is currently believed that air pollution may be related to the progression of SSNHL. As a rapidly developing city in recent years, Hefei has serious air pollution. In order to explore the correlation between meteorological variables and SSNHL admissions, we conducted this study. This study investigated the short-term associations between SSNHL patients admitted to the hospital and Hefei climatic variables. The daily data on SSNHL-related hospital admissions and meteorological variables containing mean temperature (T-mean; °C), diurnal temperature range (DTR; °C), atmospheric pressure (AP; Hp), and relative humidity (RH; %), from 2014 to 2021 (2558 days), were collected. A time-series analysis integrating distributed lag non-linear models and generalized linear models was used. PubMed, Embase, Cochrane Library, and Web of Science databases were searched. Literature published up to August 2023 was reviewed to explore the potential impact mechanisms of meteorological factors on SSNHL. The mechanisms were determined in detail, focusing on wind speed, air pressure, temperature, humidity, and air pollutants. Using a median of 50.00% as a baseline, the effect of exceedingly low T-mean in the single-day hysteresis effect model began at a lag of 8 days (RR = 1.032, 95% CI: 1.001 ~ 1.064). High DTR affected the admission rate for SSNHL on lag 0 day. The significance of the effect was the greatest on that day (RR = 1.054, 95% CI: 1.007 ~ 1.104) and then gradually decreased. High and exceedingly high RH affected the admission rate SSNHL on lag 0 day, and these effects lasted for 8 and 7 days, respectively. There were significant associations between all grades of AP and SSNHL. This is the first study to assess the effect of meteorological variables on SSNHL-related admissions in China using a time-series approach. Long-term exposures to high DTR, RH values, low T-mean values, and all AP grades enhance the incidence of SSNHL in residents. Limiting exposure to extremes of ambient temperature and humidity may reduce the number of SSNHL-related hospital visits in the region. It is advisable to maintain a suitable living environment temperature and avoid extreme temperature fluctuations and high humidity. During periods of high air pollution, it is recommended to stay indoors and refrain from outdoor exercise.


Assuntos
Poluição do Ar , Conceitos Meteorológicos , China/epidemiologia , Humanos , Poluentes Atmosféricos , Perda Auditiva Neurossensorial/epidemiologia , Temperatura , Umidade , Perda Auditiva Súbita/epidemiologia
19.
Int J Surg ; 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38905504

RESUMO

BACKGROUD: Endoscopic thyroidectomy (ET) and robotic thyroidectomy (RT) yield similar perioperative outcomes. This study investigated how the learning curve (LC) affects perioperative outcomes between ET and RT, identifying factors that influence the LC. MATERIALS AND METHODS: Two researchers individually searched PubMed, EMBASE, Web of Science, and Cochrane Library for relevant studies published until February 2024. The Newcastle-Ottawa Scale assessed study quality. Random effects model was used to compute the odds ratio and weighted mean difference (WMD). Poisson regression comparison of the number of surgeries (NLC) was required for ET and RT to reach the stable stage of the LC. Heterogeneity was measured using Cochran's Q. Publication bias was tested using funnel plots, and sensitivity analysis assessed findings robustness. Subgroup analysis was done by operation type and patient characteristics. RESULTS: This meta-analysis involved 33 studies. The drainage volume of ET was higher than that of RT (WMD=-17.56 [30.22, -4.49]). After reaching the NLC, the operation time of ET and RT was shortened (ET: WMD=28.15[18.04, 38.26]; RT: WMD=38.53[29.20, 47.86]). Other perioperative outcomes also improved to varying degrees. Notably, RT showed more refined central lymph node resection(5.67 vs. 4.71), less intraoperative bleeding (16.56 mL vs. 42.30 mL), and incidence of transient recurrent laryngeal nerve injury(24.59 vs. 26.77). The NLC of RT was smaller than that of ET(Incidence-rate ratios [IRR]=0.64[0.57, 0.72]). CUSUM analysis (ET: IRR=0.84[0.72, 0.99]; RT: IRR=0.55[0.44, 0.69]) or a smaller number of respondents (ET: IRR=0.26[0.15, 0.46]; RT: IRR=0.51[0.41, 0.63]) was associated with smaller NLC. In RT, transoral approach (IRR=2.73[1.96, 4.50]; IRR=2.48[1.61, 3.84]) and retroauricular approach (RAA) (IRR=2.13[1.26, 3.60]; IRR=1.78[1.04, 3.05]) had smaller NLC compared to bilateral axillo-breast and transaxillary approach (TAA). In ET, the NLC of RAA was smaller than that of TAA (IRR=1.61[1.04, 2.51]), breast approach(IRR=1.67[1.06, 2.64]), and subclavian approach(IRR=1.80[1.03, 3.14]). CONCLUSIONS: Rich surgical experience can improve surgical results of ET and RT. After reaching the NLC, the perioperative outcomes of RT are better than those of ET. Study subjects, surgical approaches, and analysis methods can affect NLC.

20.
J Chem Phys ; 139(20): 204709, 2013 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-24289371

RESUMO

By the first principle calculations based on the van der Waals density functional theory, we study the crystal structures and electronic properties of La-doped phenanthrene. Two stable atomic geometries of La1phenanthrene are obtained by relaxation of atomic positions from various initial structures. The structure-I is a metal with two energy bands crossing the Fermi level, while the structure-II displays a semiconducting state with an energy gap of 0.15 eV, which has an energy gain of 0.42 eV per unit cell compared to the structure-I. The most striking feature of La1phenanthrene is that La 5d electrons make a significant contribution to the total density of state around the Fermi level, which is distinct from potassium doped phenanthrene and picene. Our findings provide an important foundation for the understanding of superconductivity in La-doped phenanthrene.

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