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1.
Opt Lett ; 49(8): 1977-1980, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38621055

RESUMEN

In this work, we report on the first, to our knowledge, 2.05-µm laser based on femtosecond-laser direct written (FsLDW) Tm,Ho:YLF cladding waveguides. A channel waveguide with a 90-µm diameter "fiber-like" low-index cladding is fabricated in a 6 at. % Tm3+, 0.4 at. % Ho3+:LiYF4 crystal by FsLDW. Pumped by Ti:sapphire laser at 795.1 nm, the fabricated waveguide supports efficient lasing oscillation at 2050 nm with a maximum output power of 47.5 mW, a minimum lasing threshold of 181 mW, and a slope efficiency of 20.1%. The impacts of cavity conditions and polarizations of the pump light on the obtained lasing performance are well studied. The experimental results obtained in this study demonstrate the great potential of utilizing Tm,Ho:YLF and FsLDW for the development of durable mid-infrared lasers featuring compact designs.

2.
Appl Microbiol Biotechnol ; 108(1): 20, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38159114

RESUMEN

Soil degradation of urban greening has caused soil fertility loss and soil organic carbon depletion. Organic mulches are made from natural origin materials, and represent a cost-effective and environment-friendly remediation method for urban greening. To reveal the effects of organic mulch on soil physicochemical characteristics and fertility, we selected a site that was covered with organic mulch for 6 years and a nearby lawn-covered site. The results showed that soil organic matter, total nitrogen, and available phosphorus levels were improved, especially at a depth of 0-20 cm. The activities of cellulase, invertase, and dehydrogenase in soil covered with organic mulch were 17.46%, 78.98%, and 283.19% higher than those under lawn, respectively. The marker genes of fermentation, aerobic respiration, methanogenesis, and methane oxidation were also enriched in the soil under organic mulch. Nitrogen cycling was generally repressed by the organic mulch, but the assimilatory nitrate and nitrite reduction processes were enhanced. The activity of alkaline phosphatase was 12.63% higher in the mulch-covered soil, and functional genes involved in phosphorus cycling were also enriched. This study presents a comprehensive investigation of the influence of organic mulch on soil microbes and provides a deeper insight into the recovery strategy for soil degradation following urban greening. KEY POINTS: • Long-term cover with organic mulches assists soil recovery from degradation • Soil physical and chemical properties were changed by organic mulches • Organic mulches enhanced genes involved in microbially mediated C and P cycling • Soil organic matter was derived from decomposition of organic mulch and carbon fixation • N cycling was repressed by mulches, except for assimilatory NO2- and NO3- reductions.


Asunto(s)
Carbono , Suelo , Suelo/química , Microbiología del Suelo , Nitrógeno , Fósforo
3.
Microb Ecol ; 86(2): 985-996, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36585489

RESUMEN

Inland saline-alkaline wetlands distributed in the mid-high latitude have repeatedly experienced freezing and thawing. However, the response of greenhouse gas (GHG) emission and microbially-mediated carbon and nitrogen cycle to freezing and thawing remains unclear. We monitored the GHG flux in an inland saline-alkaline wetland and found that, compared with the growth period, the average CO2 flux decreased from 171.99 to 76.61-80.71 mg/(m2‧h), the average CH4 flux decreased from 10.72 to 1.96-3.94 mg/(m2‧h), and the average N2O flux decreased from 56.17 to - 27.14 to - 20.70 µg/(m2‧h). Freezing and thawing significantly decreased the relative abundance of functional genes involved in carbon and nitrogen cycles. The aceticlastic methanogenic pathway was the main methanogenic pathway, whereas the Candidatus Methylomirabilis oxyfera was the most abundant methane oxidizer in the wetland. Ammonia-oxidizing archaea and denitrifier belonging to proteobacteria was the major microbial N2O source, while bacteria within clade II nosZ was the major microbial N2O sink. Freezing and thawing reduced the relative abundance of these genes, leading to a decrease in GHG flux.


Asunto(s)
Gases de Efecto Invernadero , Humedales , Congelación , Dióxido de Carbono , Óxido Nitroso , Carbono , Metano/análisis , Suelo
4.
Prenat Diagn ; 43(7): 901-909, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37150864

RESUMEN

OBJECTIVE: To study the ultrasonographic features of the central nervous system (CNS) in normally developing embryos and fetuses with a crown-rump length (CRL) of 10-84 mm, utilizing a high-frequency transvaginal probe in conjunction with various three-dimensional (3D) imaging modes. METHODS: From January 2020 to February 2021, 210 normally developing embryos and fetuses in early pregnancy were enrolled and classified based on their gestational age. A high-frequency transvaginal transducer was used to perform 2D and 3D ultrasounds, and the 3D images were saved. These images were then processed using multiple 3D technologies, such as HD live silhouette, OmniView, and TUI. Additionally, the circumference of the vermis was measured through the posterior fontanelle. RESULTS: Beginning at the 10 mm CRL stage of embryonic development, high-frequency transvaginal 3D ultrasound imaging was able to clearly visualize the prosencephalon, mesencephalon, and rhombencephalon. Notable changes were observed in the rhombencephalon during the 16-22 mm CRL stage, including the visualization of the pontine flexure and cerebellar primordium. At 23-40 mm CRL, there was a distinct pontine flexure, and the developing cerebellum, the fourth ventricle, and choroid plexus of the fourth ventricle (4th VCP) could be observed. The roof of the rhombencephalon was partitioned by the 4th VCP into the anterior membranous area (AMA) located rostrally and the posterior membranous area situated caudally. Additionally, the original Blake's pouch was identifiable. Among fetuses measuring 41-84 mm CRL, the AMA progressively decreased in size as the vermis developed. From the mid-sagittal view, the orientation of the 4th VCP seemed to shift from being perpendicular to the neural tube's long axis to being parallel to it. Furthermore, there was a significant correlation between CRL and vermis circumference. CONCLUSION: Using three-dimensional transvaginal ultrasound scanning, detailed visualization of the morphological changes in the CNS during normal embryonic development from 7 to 13+6  weeks is possible. This technology can aid in accurately characterizing the embryonic origin of the CNS.


Asunto(s)
Rombencéfalo , Ultrasonografía Prenatal , Embarazo , Femenino , Humanos , Ultrasonografía Prenatal/métodos , Edad Gestacional , Ultrasonografía , Puente/diagnóstico por imagen , Imagenología Tridimensional
5.
BMC Microbiol ; 22(1): 208, 2022 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-36042394

RESUMEN

BACKGROUND: Soil microbiome is an important part of the forest ecosystem and participates in forest ecological restoration and reconstruction. Niche differentiation with respect to resources is a prominent hypothesis to account for the maintenance of species diversity in forest ecosystems. Resource-based niche differentiation has driven ecological specialization. Plants influence soil microbial diversity and distribution by affecting the soil environment. However, with the change in plant population type, whether the distribution of soil microbes is random or follows an ecologically specialized manner remains to be further studied. We characterized the soil microbiome (bacteria and fungi) in different plant populations to assess the effects of phytophysiognomy on the distribution patterns of soil microbial communities in a temperate forest in China. RESULTS: Our results showed that the distribution of most soil microbes in different types of plant populations is not random but specialized in these temperate forests. The distribution patterns of bacteria and fungi were related to the composition of plant communities. Fungal species (32%) showed higher specialization than bacterial species (15%) for different types of plant populations. Light was the main driving factor of the fungal community, and soil physicochemical factors were the main driving factor of the bacterial community. CONCLUSION: These findings suggest that ecological specialization is important in maintaining local diversity in soil microbial communities in this forest. Fungi are more specialized than bacteria in the face of changes in plant population types. Changes in plant community composition could have important effects on soil microbial communities by potentially influencing the stability and stress resistance of forest ecosystems.


Asunto(s)
Microbiota , Micobioma , Bacterias/genética , China , Ecosistema , Bosques , Hongos/genética , Plantas/microbiología , Suelo/química , Microbiología del Suelo
6.
Opt Express ; 29(3): 4296-4307, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33771012

RESUMEN

Low-loss depressed cladding waveguide architecture is highly attractive for improving the laser performance of waveguide lasers. We report on the design and fabrication of the "ear-like" waveguide structures formed by a set of parallel tracks in neodymium-doped yttrium aluminum garnet (Nd:YAG) crystal via femtosecond laser writing. The obtained "ear-like" waveguides are with more symmetric mode profiles and lower losses by systematically comparing the guiding properties of two kinds of normal cladding waveguide. Efficient waveguide lasers are realized based on the designed structure in both continuous wave and pulsed regimes. Combined the high-gain from cladding waveguide and special "ear-like" structure, a passively fundamentally Q-switched laser with the narrow pulse width and the high repetition rate has been obtained by using tin diselenide (SnSe2) as saturable absorber.

7.
J Clin Pharm Ther ; 46(3): 705-710, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33403672

RESUMEN

WHAT IS KNOWN AND OBJECTIVE: In recent years, the resistance of Mycoplasma pneumoniae to macrolide antibiotics has increased significantly. The health systems are facing significant challenges in carrying out the diagnosis and treatment of refractory Mycoplasma pneumoniae pneumonia in children. Levofloxacin is suitable for treating infectious diseases in various systems but limited in children due to arthropathy issues in weight-bearing joints. This study aimed to evaluate the efficacy and safety of levofloxacin in children with macrolide-resistant Mycoplasma pneumoniae pneumonia. METHODS: We retrospectively enrolled six confirmed cases of refractory Mycoplasma pneumoniae pneumonia who were admitted in the paediatric respiratory ward of Shandong provincial hospital Affiliated to Shandong first Medical University between 1st January 2020 and 29th February 2020. Levofloxacin was given to the patients through the intravenous or oral route as per the following dosages :<5 years, 8-10 mg/kg q12 h; >5 years, 8-10 mg/kg, qd for 10 days. The clinical data were collected and analysed. RESULTS AND DISCUSSION: The average age of the enrolled cases was six years and nine months (range, four years, and seven months to eleven years and seven months). All cases were found to be drug-resistant and were treated with azithromycin combined with antibacterial drugs. Levofloxacin was used in the patient's refractory to macrolide antibiotics. The temperature of five cases returned to normal 1-2 days after treatment with levofloxacin, and the imaging of the four cases showed expected improvements. The gastrointestinal symptoms, neurological manifestations, joint symptoms, blood parameters, liver and kidney functions, and exercise conditions of the children were closely monitored. The follow-up time of the patients ranged from one week to five months. No drug-related adverse reactions were observed in patients during treatment or during follow-up. WHAT IS NEW AND CONCLUSION: The clinical symptoms and imaging significantly improved after treatment with levofloxacin, and no drug-related adverse reactions were observed. Levofloxacin proved to be an effective and safe drug in the treatment of children with macrolide-resistant mycoplasma pneumonia. This study will provide a reference for evaluating the efficacy and safety of levofloxacin in the paediatric population.


Asunto(s)
Antibacterianos/uso terapéutico , Levofloxacino/uso terapéutico , Macrólidos/farmacología , Neumonía por Mycoplasma/tratamiento farmacológico , Antibacterianos/efectos adversos , Antibacterianos/farmacología , Niño , Preescolar , Relación Dosis-Respuesta a Droga , Farmacorresistencia Bacteriana , Femenino , Humanos , Levofloxacino/efectos adversos , Levofloxacino/farmacología , Masculino , Estudios Retrospectivos
8.
Ecotoxicol Environ Saf ; 189: 110015, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31830602

RESUMEN

This paper adopts a novel data-processing method of ECSA® based on TG/DSC-MS system to basically study the characteristics of release and conversion of fluorides and cyanides during heat treatment of the spent cathode carbon block (SCCB). All the experiments were conducted at 10 K⋅min-1 heating rate and under Ar or Ar-O2 atmospheres. The results indicate that the release of fluorides was just a steady but slow phase transition process under both Ar and Ar-O2 atmospheres, which can be comparatively accelerated when the carbon material was burnt. The cyanides were effectively decomposed at high temperature and at Ar-O2 atmosphere, with around three quarters of the cyanides being converted to the N2 and nearly a quarter being to the NO. Finally, analysis on the flue gas composition indicates that it had a more complicated composition of CO2, N2, NO, NO2, HCN under Ar-O2 atmosphere but only had a composition of CO2 and NO under Ar atmosphere.


Asunto(s)
Contaminantes Atmosféricos/química , Carbono/química , Cianuros/química , Electrodos , Fluoruros/química , Contaminantes Atmosféricos/análisis , Aluminio , Argón/química , Atmósfera/química , Cianuros/análisis , Fluoruros/análisis , Calor , Metalurgia , Eliminación de Residuos
10.
Appl Microbiol Biotechnol ; 102(19): 8561-8571, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30030565

RESUMEN

As an interface of terrestrial and aquatic ecosystems, wetland is a hotspot of the global nitrogen cycle. Ammonia oxidation is an essential part of the nitrogen cycle and is conducted by ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB). Based on the amoA gene, the distribution and genetic diversity of AOA and AOB in the marsh wetland soil with different soil layers and vegetation had been investigated. The result showed that both soil layer and vegetation significantly influenced the diversity and abundance of AOA and AOB. AOB dominated numerically in all soil samples. The average bacterial amoA gene copies (2.62 × 109 copies/g dry soil) was 100-fold higher than the average archaeal amoA gene copies. In the soil sample under the Phragmites australis, the highest archaeal amoA gene was in depth 20-40 cm, whereas the bacterial amoA gene was more abundant in depth 0-20 cm. For the soil under Calamagrostis angustifolia, the highest archaeal and bacterial amoA gene were both detected in depth 0-20 cm. The dominated AOA was cluster AII, which was most related to the amoA gene found in aquatic habitat. Cluster BI accounted for 59.1% of bacterial amoA gene and it was related to the amoA gene found in the terrestrial habitat. CCA analysis revealed that NO3- was the main factor for AOA and AOB community structure in the P. australis soil. However, NO2- and NH4+ were important factors for AOA and AOB in the soil under C. angustifolia.


Asunto(s)
Amoníaco/metabolismo , Archaea/genética , Bacterias/genética , Biodiversidad , China , Ecosistema , Genes Bacterianos/genética , Ciclo del Nitrógeno/genética , Oxidación-Reducción , Filogenia , Poaceae/microbiología , Suelo , Microbiología del Suelo , Humedales
11.
Appl Microbiol Biotechnol ; 102(16): 7195-7205, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29948120

RESUMEN

Ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) contribute significantly to the nitrogen cycle. The community structure of AOA and AOB is diverse in the different wetlands. Few studies have comparatively investigated the community structure and dynamics of ammonia-oxidizing organisms in the marsh wetland (Sanjiang wetland) and inland saline-alkaline wetland (Zhalong wetland) in Northeast China. In this study, soil samples were collected from two wetlands with different soil properties in July and October. The community structure of AOA and AOB based on the amoA gene was investigated by high throughput sequencing. The result showed that AOA affiliated to the Nitrososphaera lineage (1.1b group) were the dominant AOA in both Sanjiang and Zhalong wetlands, while AOB belonging to the Nitrosospira lineage was the dominant AOB in the Sanjiang wetland. AOB belonging to the Nitrosospira lineage and Nitrosomonas lineage were the dominant AOB in the Zhalong wetland in July and October, respectively. The dominant AOA and AOB in the Sanjiang wetland had no obvious variation from July to October, but the AOA and AOB communities in the Zhalong wetland changed a lot from July to October. Shannon and Simpson indexes showed the diversity of AOA in the Zhalong wetland was higher than that in the Sanjiang wetland, but the diversity of AOB in the Zhalong wetland was lower than that in the Sanjiang wetland. Nitrate (NO3-) and ammonium (NH4+) concentration and pH were the most significant factors influencing the community structure of AOA and AOB.


Asunto(s)
Archaea/fisiología , Fenómenos Fisiológicos Bacterianos , Monitoreo del Ambiente , Microbiología del Suelo , Humedales , Amoníaco/metabolismo , China , Suelo/química , Factores de Tiempo
12.
Front Oncol ; 14: 1390006, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38863635

RESUMEN

Lung cancer remains one of the leading causes of cancer-related mortality worldwide necessitating the development of innovative therapeutic strategies. Chimeric antigen receptor (CAR) natural killer (NK) cell therapy represents a promising advancement in the field of oncology offering a novel approach to target and eliminate tumor cells with high specificity and reduced risk of immune-related adverse effects. This paper reviews the mechanism, potential targets, and recent advances in CAR-NK cell therapy for lung cancer, including the design and engineering of CAR-NK cells, preclinical studies, and the outcomes of early-phase clinical trials. We highlight the unique advantages of using NK cells, such as their innate ability to recognize and kill cancer cells and their reduced potential for inducing graft-versus-host disease (GvHD) and cytokine release syndrome (CRS) compared to CAR T-cell therapies. Results from recent studies demonstrate significant antitumor activity in lung cancer models with improved targeting and persistence of CAR-NK cells observed in vitro and in vivo. Finally, we discuss the challenges in optimizing CAR-NK cell therapies, including the potential resistance mechanisms. The paper concludes with an outlook on the future directions of CAR-NK cell research and its implications for lung cancer treatment emphasizing the importance of continued innovation and collaboration in the field.

13.
Sci Total Environ ; 919: 170856, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38340836

RESUMEN

Inland alkaline wetlands play a crucial role in maintaining ecological functions. However, these wetlands are becoming more vulnerable to the effects of water level fluctuations caused by global climate change, especially concerning carbon (C) and nitrogen (N) cycling. Here, metagenomics sequencing was used to investigate microorganism diversity, C and N cycling gene abundance at three water level types (D (dry), MF (middle flooded), HF (high flooded)) along an inland alkaline wetland. Our findings reveal that water level was the most important factor in regulating the microbial communities. Distinct shifts in community composition were found along the water level increases, without fundamentally altering their composition. With the increase of water level, the relative abundance of pmoA decreased from 2.5 × 10-5 to 5.1 × 10-6. The C cycling processes shift from predominantly CO2-generated processes under low water levels to CO2 and CH4 co-generated processes under high water levels. The relative abundance of nosZ reached 4.9 × 10-5 in HF, while in D and MF, it is recorded at 4.5 × 10-5 and 3.4 × 10-5, respectively. Water levels accelerate N cycling and generating N2O intermediates. Furthermore, our study highlights the dynamic competition and cooperation between C and N cycling processes. This research provides a comprehensive biological understanding of the influence of varying water levels on soil C and N cycling processes in wetland.


Asunto(s)
Nitrógeno , Humedales , Carbono , Dióxido de Carbono/análisis , Suelo , Metano/análisis , Metano/química , Óxido Nitroso/análisis , Óxido Nitroso/química
14.
Chemosphere ; 362: 142640, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38901697

RESUMEN

Exogenous quorum sensing (QS) molecular can regulate the activity and granulation process of anaerobic sludge in anaerobic digestion process, but would be impractical as a standalone operation. Here we demonstrated that application of 1 mg L-1 boric acid assisted in an upflow anaerobic sludge blanket (UASB) reactor recovery from volatile fatty acids (VFAs) accumulation. After VFAs accumulation, the chemical oxygen demand (COD) removal suddenly reduced from 78.98% to 55.86%. The relative abundance of acetoclastic methanogens decreased from 55.79% to 68.28%-23.14%∼25.41%, and lead to the acetate accumulate as high as 1317.03 mg L-1. Granular sludge disintegrated and the average size of sludge decreased to 586.38 ± 42.45 µm. Application of 1 mg L-1 boric acid activated the interspecies QS signal (AI-2) and then induced the secretion of intraspecies QS signal (N-acyl-homoserine lactones, AHLs). AHLs were then stimulated the growth of syntrophic acetate oxidizing bacteria and hydrogenotrophic methanogen. Moreover, the concentration of acetate decreased to 224.50 mg‧L-1, and the COD removal increased to 75.10% after application of 1 mg L-1 boric acid. The activated AI-2 may induce multiple quorum-sensing circuits enhance the level of AI-2 and AHLs in parallel, and in turn assisted in anaerobic digestion recovery from VFAs accumulation.


Asunto(s)
Reactores Biológicos , Ácidos Grasos Volátiles , Percepción de Quorum , Aguas del Alcantarillado , Ácidos Grasos Volátiles/metabolismo , Anaerobiosis , Aguas del Alcantarillado/microbiología , Reactores Biológicos/microbiología , Boro , Eliminación de Residuos Líquidos/métodos , Ácidos Bóricos/metabolismo , Análisis de la Demanda Biológica de Oxígeno , Bacterias/metabolismo , Acil-Butirolactonas/metabolismo
15.
Opt Express ; 21(12): 13992-7, 2013 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-23787589

RESUMEN

A high-gain optical waveguide amplifier has been realized in a channel waveguide platform of Nd:YAG ceramic produced by swift carbon ion irradiation with metal masking. The waveguide is single mode at wavelength of 810 and 1064 nm, and with the enhanced fluorescence intensity at around 1064 nm due to the Nd(3+) ion emissions. In conjunction with the low propagation loss of the waveguide, about 26.3 dB/cm of the small signal gain at 1064 nm is achieved with an 18 ns pulse laser as the seeder under the 810-nm laser excitation. This work suggests the carbon ion irradiated Nd:YAG waveguides could serve as efficient integrated amplifiers for the signal amplification.


Asunto(s)
Amplificadores Electrónicos , Cerámica/química , Cerámica/efectos de la radiación , Refractometría/instrumentación , Resonancia por Plasmón de Superficie/instrumentación , Diseño de Equipo , Análisis de Falla de Equipo , Iones Pesados
16.
Opt Express ; 21(16): 18963-8, 2013 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-23938810

RESUMEN

This work reports on the Q-switched pulsed laser generation from double-cladding Nd:YAG ceramic waveguides. Double-cladding waveguides with different combination of diameters were inscribed into a sample of Nd:YAG ceramic. With an additional semiconductor saturable absorber, stable pulsed laser emission at the wavelength of 1064 nm was achieved with pulses of 21 ns temporal duration and ~14 µJ pulse energy at a repetition rate of 3.65 MHz.

17.
Sci Total Environ ; 891: 164190, 2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37196954

RESUMEN

The hormetic response of microbes to cadmium (Cd) is often observed in soil, but the mechanisms are unclear. In this study, we proposed a novel perspective of hormesis that successfully explained the temporal hermetic response of soil enzymes and microbes, and the variation of soil physicochemical properties. Several soil enzymatic and microbial activities were stimulated by 0.5 mg·kg-1 exogenous Cd, but inhibited at higher Cd dosages. The phenomena suggested the hormetic response to 0.5 mg·kg-1 Cd was highly generalizable concerning soil enzymes and microbial activity. However, the response disappeared after incubation for >10 days. Soil respiration was also initially enhanced by exogenous Cd and decreased after consumption of labile soil organic matter. The metagenomic results revealed Cd stimulation of genes involved in labile soil organic matter decomposition. Additionally, Cd enriched the antioxidant enzymatic activity and abundances of the corresponding marker genes, rather than genes involved in the efflux-mediated heavy metal resistance. The microbes enhanced their primary metabolism to make up the energy gaps, with hormesis evident. The hormetic response disappeared after the labile compounds in soil were exhausted. Overall, this study illustrates the dose-dependence and temporal variation of stimulants and provides a novel and feasible strategy for the study of Cd in soil microorganisms.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Cadmio/análisis , Hormesis , Suelo/química , Contaminantes del Suelo/análisis , Microbiología del Suelo
18.
Sci Total Environ ; 899: 166372, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37598964

RESUMEN

The effects of cadmium (Cd) contamination on the assembly mechanism and co-occurrence patterns of arbuscular mycorrhizal (AM) fungal communities remain unclear, especially in urban green spaces. This study sequenced AM fungal communities in greenbelt soils in Zhengzhou (China). The effects of Cd contamination on the AM fungal diversity, community assembly processes, and co-occurrence patterns were explored. We found that (1) an increase in Cd contamination changed the community composition, which resulted in a significant improvement in the diversity of specialists of AM fungi and a significant decrease in the diversity of generalists. (2) Deterministic processes dominated the community assembly of specialists and stochastic processes dominated the community assembly of generalists. (3) Specialists played a more important role than generalists in maintaining the stability of AM fungal networks under Cd contamination. Overall, Cd contamination affected the ecological processes of AM fungi in urban green space ecosystems. However, the effects on the assembly processes and network stability of different AM fungi taxa (specialists and generalists) differed significantly. The present study provides deeper insight into the effect of Cd contamination on the ecological processes of AMF and is helpful in further exploring the ecological risk of Cd contamination in urban green spaces.


Asunto(s)
Micobioma , Micorrizas , Cadmio , Ecosistema , Parques Recreativos , China
19.
Proc Natl Acad Sci U S A ; 106(8): 2694-9, 2009 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-19196962

RESUMEN

Hirschsprung's disease (HSCR), or aganglionic megacolon, is a congenital disorder characterized by the absence of enteric ganglia in variable portions of the distal intestine. RET is a well-established susceptibility locus, although existing evidence strongly suggests additional loci contributing to sporadic HSCR. To identify these additional genetic loci, we carried out a genome-wide association study using the Affymetrix 500K marker set. We successfully genotyped 293,836 SNPs in 181 Chinese subjects with sporadic HSCR and 346 ethnically matched control subjects. The SNPs most associated with HSCR were genotyped in an independent set of 190 HSCR and 510 control subjects. Aside from SNPs in RET, the strongest overall associations in plausible candidate genes were found for 2 SNPs located in intron 1 of the neuregulin1 gene (NRG1) on 8p12, with rs16879552 and rs7835688 yielding odds ratios of 1.68 [CI(95%):(1.40, 2.00), P = 1.80 x 10(-8)] and 1.98 [CI(95%):(1.59, 2.47), P = 1.12 x 10(-9)], respectively, for the heterozygous risk genotypes under an additive model. There was also a significant interaction between RET and NRG1 (P = 0.0095), increasing the odds ratio 2.3-fold to 19.53 for the RET rs2435357 risk genotype (TT) in the presence of the NRG1 rs7835688 heterozygote, indicating that NRG1 is a modifier of HSRC penetrance. Our highly significant association findings are backed-up by the important role of NRG1 as regulator of the development of the enteric ganglia precursors. The identification of NRG1 as an additional HSCR susceptibility locus not only opens unique fields of investigation into the mechanisms underlying the HSCR pathology, but also the mechanisms by which a discrete number of loci interact with each other to cause disease.


Asunto(s)
Predisposición Genética a la Enfermedad , Genoma Humano , Enfermedad de Hirschsprung/genética , Proteínas del Tejido Nervioso/genética , Femenino , Marcadores Genéticos , Estudio de Asociación del Genoma Completo , Humanos , Masculino , Neurregulina-1 , Polimorfismo de Nucleótido Simple , Proteínas Proto-Oncogénicas c-ret/genética
20.
Comput Intell Neurosci ; 2022: 5759986, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35996652

RESUMEN

With the development of art education and information technology, it is increasingly necessary to use computer technology and multimedia technology to assist teaching in the teaching activities of music subjects nowadays, so as to cultivate students' independent inquiry ability and drilling ability. The design of an interactive teaching music intelligence system based on artificial intelligence is studied, and a music learning model based on the RBF algorithm is proposed, which helps to enhance students' inquiry ability and also plays the leading role of teachers. By teaching each other, students become the main subject of teaching and learning, and it stimulates students' enthusiasm and learning awareness of music learning.


Asunto(s)
Música , Inteligencia Artificial , Humanos , Aprendizaje , Estudiantes
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