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1.
Heliyon ; 9(4): e15255, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37096000

RESUMO

Background: Previous studies have suggested that point-of-care ultrasound could help to evaluate and diagnose pediatric skull fracture for the closed scalp hematoma from blunt trauma. However, relevant data in Chinese children are missing, especially in children 0-6 years old. Objectives: Our study aimed to evaluate the efficacy of point-of-care ultrasound to diagnose skull fracture in children 0-6 years old with scalp hematoma in China. Methods: We performed a prospective observational study and screened children 0-6 years old with closed scalp hematoma and a Glasgow coma scale of 14-15 at Hospital in China. Enrolled children (N = 152) were first evaluated for skull fracture with point-of-care ultrasound by the emergency physician and then received a head computed tomography scan. Results: The point-of-care ultrasound examination and computed tomography scan revealed skull fracture in 13 (8.6%) and 12 (7.9%) children, respectively. The kappa test showed a satisfactory agreement between two examinations (P < 0.0001), with kappa = 0.87 (95% confidence interval, i.e., 95% CI, [0.69, 1.00]) and area under the curve = 0.95 (95% CI [0.86, 1], P < 0.0001). The point-of-care ultrasound examination had the sensitivity of 91.7% (95% CI [62.5%, 100%]), specificity of 98.6% (95% CI [94.6%, 100%]), positive predictive value of 84.6% (95% CI [56.5%, 96.9%]), negative predictive value of 99.2% (95% CI [95.6%, 100%]), and accuracy of 98.0% (95% CI [94.1%, 99.6%]). Conclusions: While our study is preliminary in nature, our findings may guide future larger studies in assessing the utility of point-of-care ultrasound examination in diagnosing skull fractures in children with scalp hematoma from minor head trauma.

2.
Micromachines (Basel) ; 13(12)2022 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-36557478

RESUMO

With the development of microelectronic technology, the integration of electronic systems is increasing continuously. Electronic systems are becoming more and more sensitive to external electromagnetic environments. Therefore, to improve the robustness of radio frequency (RF) microwave circuits, it is crucial to study the reliability of semiconductor devices. In this paper, the temporary failure mechanism of a gallium arsenide (GaAs) pseudomorphic high electron mobility transistor (pHEMT) in a navigation low-noise amplifier (LNA) under the jamming of ultra-wideband (UWB) electromagnetic pulses (EMP) is investigated. The failure process and failure mechanism of pHEMT under UWB EMP are elaborated by analyzing the internal electric field, current density, and temperature distribution. In detail, as the amplitude of UWB EMP increases, the output current, carrier mobility, and transconductance of pHEMT decrease, eventually resulting in gain compression. The injection experiment on LNA, which effectively verified the failure mechanism, indicates that the gain of pHEMT is suppressed instantaneously under the jamming of UWB EMP and the navigation signal cannot be effectively amplified. When UWB EMP amplitude increases to nearly 10 V, the BeiDou Navigation Satellite System (BDS) carrier signal is suppressed by nearly 600 ns. Experimental results accord well with the simulation of our model. UWB EMP jamming is a new and efficient type of electromagnetic attack system based on the device saturation effect. The performance degradation and failure mechanism analysis contribute to RF reinforcement design.

3.
Sci Total Environ ; 814: 151942, 2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-34843791

RESUMO

Shelterbelt farmland afforestation has been well-reported in its wind-break and climate regulation function, but less is on underground-soil organic carbon (SOC) sequestration and environmental stability. In this paper, we collected 180 soil samples from soil depths of 1 m (0-20, 20-40, 40-60, 60-80, 80-100 cm) in the farmland and neighbor shelterbelts in Songnen Plain, northeastern China. The sample plots covered six regions in the study area. SOC concentration and respiration decomposition rate, Q10 (temperature sensitivity), Hs (humidity sensitivity) were determined in the laboratory cultivation. Soil properties (N, P, K, electrical conductivity-EC, pH) and geographic-climate factors (multiple-year mean annual temperature and precipitation, MAT&MAP; temperature and precipitation during sampling month, MT &MP) were used to reveal the underlying reason for the changes in soil carbon sequestration. The results showed no significant difference in SOC respirational decomposition rate between farmland and shelterbelt forests but a 15.8% higher SOC concentration in shelterbelt forests (p < 0.05). The poplar shelterbelts reduced the Q10 value by 15.4% (p < 0.05), with deeper soils a more significant reduction in Q10. With soil moisture increases, both shelterbelt forests and farmland showed an obvious respiration pattern of first-increasing-then-decreasing. No significant Hs (linear gradients) differences were found in farmland and shelterbelt forests. Partitioning of the RDA ordination-based variation showed that SOC stability (Hs and Q10) of farmland was more affected by geo-climate. In contrast, the SOC stability of shelterbelt forests was greatly influenced by soil properties. Our findings manifest that the above-mentioned SOC changes can improve shelterbelt forest carbon sequestration function by prolonging the SOC lifespan in soil by at least 7% and SOC concentration by >15%. This should be included in the future to assess the underground soil carbon impact of Three-North shelterbelts in China and provide data supports for the estimation of similar forest stands in other parts of the world.


Assuntos
Carbono , Solo , Carbono/análise , Sequestro de Carbono , China , Fazendas , Florestas , Temperatura
4.
Plant Physiol Biochem ; 162: 150-160, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33684774

RESUMO

Nitrogen (N) deposition affects plant growth and interspecific interaction. This study aimed to explore the effect of N deposition on the growth and eco-physiological interactions between two tree species dominating in subtropical forests. A greenhouse experiment was conducted for 6 months in which the conifer Cunninghamia lanceolata and the broadleaved Phoebe chekiangensis were grown in monocultures and in a mixture under two levels of N addition: 0 and 45 kg ha-1 yr-1. The plant growth, root architecture, biomass distribution, element contents in plants and soil, and photosynthetic physiology were determined. The height and crown width of both seedlings tended to be higher in the mixture than in the monoculture when grown without N addition. P. chekiangensis was superior to C. lanceolata in resource acquisition and showed a greater net photosynthetic rate, plant height, crown width, total biomass, and belowground biomass distribution. In the mixture, N addition increased the net photosynthetic rate and decreased the height, ground diameter, and crown width of both species. Belowground biomass distribution was decreased in C. lanceolata but increased in P. chekiangensis under N addition. The P contents in both seedlings were higher in the mixture than in monocultures. Results showed N addition aggravated the competition and weakened the growth of both species in the mixture, largely determined by the competition for resources through the changing root architecture and biomass allocation. Our results provide new insights into the mechanisms of interspecific interaction in response to increasing N deposition in silvicultural practice.


Assuntos
Cunninghamia , Árvores , Biomassa , Florestas , Nitrogênio , Solo
5.
Front Oncol ; 10: 1330, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32923385

RESUMO

Background: Increasing evidence has indicated an association between differentially expressed genes (DEGs) in tumor-infiltrating immune cells (TIICs) and clinical outcome. The aim of this research is to investigate the influence of tumor microenvironment on the gene expression profile of TIICs and to identify their potential markers for modulating immune cell function in prostate cancer. Methods: In our research, CIBERSORT algorithm was utilized to calculate the proportion of the TIICs in 164 tumor and 18 control samples from The Cancer Genome Atlas cohort. The differential expression analysis was conducted using R, and then the functional and the pathway enrichments of the DEGs were analyzed using Database for Annotation, Visualization, and Integrated Discovery, followed by integrated regulatory network analysis. Results: As a result, nTreg, B cells, Th1, and DC cells were significantly increased, accompanied by largely decreased NK and NKT cells. The expressed immune-related gene correlation analysis showed that the signature gene expression extent of CD8 T cells was positively associated with CD4 memory activated T cells but negatively correlated with that of CD4 memory resting T cells. In addition, a total of 128 differentially expressed genes were identified. CytoHubba analysis obtained six hub genes, of which three prognostic-associated potential key molecules including CAV1, FLNA, and VCL were mainly involved in biological processes associated with the regulation of organic substance and synaptic connections. Conclusions: This study provides a comprehensive understanding of the landscape of TIICs and the roles of the hub genes which may be valuable markers in prostate cancer diagnosis and immunotherapy.

6.
Plant Physiol Biochem ; 153: 81-91, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32485616

RESUMO

Drought stress influences the growth of plants and thus grafting has been widely used to improve tolerance to abiotic stresses. Poplars possess sex-specific responses to drought stress, but how male or female rootstock affect the grafted plant is little known. To explore the mechanisms underlying changes in drought tolerance caused by grafting, we investigated the changes in growth, leaf traits, gas exchange and antioxidant enzyme activities of reciprocally grafted seedlings between Populus euramericana cv. "Nanlin895" (NL-895) (female) and Populus deltiodes cv."3412" (NL-3412) (male) under water deficit stress with 30% field capacity for 30 d. Results showed that drought stress affected adversely growth, morphological, and physiological characteristics in all seedlings studied. Grafted seedlings with male roots can effectively alleviated the inhibition of growth induced by drought stress, as shown by higher WUE, activities of SOD, POD and CAT, and lower levels of lipid peroxidation. Male seedlings with female roots were found to be less tolerance to drought than non-grafted male clones and female scions with male roots, but more tolerance than non-grafted female clones. This results suggested that drought tolerance of grafted seedlings is primarily caused by the rootstock, although the scion also affects the grafted plant. Thus, paying attention on the root genotype can provide an important means of improving the drought tolerance of poplars.


Assuntos
Secas , Raízes de Plantas/fisiologia , Populus/fisiologia , Estresse Fisiológico , Genótipo , Folhas de Planta , Raízes de Plantas/classificação , Populus/classificação , Plântula
7.
Aging (Albany NY) ; 11(24): 12754-12772, 2019 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-31895690

RESUMO

Docetaxel is a first-line anticancer drug widely used in the treatment of advanced prostate cancer. However, its therapeutic efficacy is limited by its side effects and the development of chemoresistance by the tumor. Using a gene differential expression microarray, we identified 449 genes differentially expressed in docetaxel-resistant DU145 and PC3 cell lines as compared to docetaxel-sensitive controls. Moreover, western blotting and immunohistochemistry revealed altered expression of S100A4, ACKR3 and CDH1in clinical tumor samples. Cytoscape software was used to investigate the relationship between critical proteins and their signaling transduction networks. Functional and pathway enrichment analyses revealed that these signaling pathways were closely related to cellular proliferation, cell adhesion, cell migration and metastasis. In addition, ACKR3 knockout using the crispr/cas9 method andS100A4knockdownusing targeted shRNA exerted additive effects suppressing cancer cell proliferation and migration. This exploratory analysis provides information about potential candidate genes. It also provides new insight into the molecular mechanism underlying docetaxel-resistance in androgen-independent prostate cancer and highlights potential targets to improve therapeutic outcomes.


Assuntos
Antígenos CD/genética , Caderinas/genética , Docetaxel/farmacologia , Receptores CXCR/genética , Proteína A4 de Ligação a Cálcio da Família S100/genética , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular , Resistencia a Medicamentos Antineoplásicos/genética , Deleção de Genes , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Masculino , Neoplasias da Próstata/genética , Transcriptoma
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