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1.
BMC Cancer ; 24(1): 11, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38166700

RESUMO

OBJECTIVE: The aim of this study was to investigate the clinical, imaging and pathological features of extraskeletal osteosarcoma (EOS) and to improve the understanding of this disease and other similar lesions. METHODS: The data for 11 patients with pathologically confirmed extraosseous osteosarcoma, including tumour site and size and imaging and clinical manifestations, were analysed retrospectively. RESULTS: Six patients were male (60%), and 5 were female (40%); patient age ranged from 23 to 76 years (average age 47.1 years). Among the 11 patients, 7 had clear calcifications or ossification with different morphologies, and 2 patients showed a massive mature bone tumour. MRI showed a mixed-signal mass with slightly longer T1 and T2 signals in the tumour parenchyma. Enhanced CT and MRI scans showed enhancement in the parenchyma. Ten patients had different degrees of necrosis and cystic degeneration in the mass, 2 of whom were complicated with haemorrhage, and MRI showed "fluid‒fluid level" signs. Of the 11 patients, five patients survived after surgery, and no obvious recurrence or metastasis was found on imaging examination. One patient died of lung metastasis after surgery, and 2 patients with open biopsy died of disease progression. One patient died of respiratory failure 2 months after operation. 2 patients had positive surgical margins, and 1 had lung metastasis 6 months after operation and died 19 months after operation. Another patient had recurrence 2 months after surgery. CONCLUSION: The diagnosis of EOS requires a combination of clinical, imaging and histological examinations. Cystic degeneration and necrosis; mineralization is common, especially thick and lumpy mineralization. Extended resection is still the first choice for localized lesions. For patients with positive surgical margins or metastases, adjuvant chemoradiotherapy is needed.


Assuntos
Neoplasias Ósseas , Neoplasias Pulmonares , Osteossarcoma , Neoplasias de Tecidos Moles , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Adulto Jovem , Adulto , Idoso , Diagnóstico Diferencial , Margens de Excisão , Estudos Retrospectivos , Neoplasias de Tecidos Moles/patologia , Imageamento por Ressonância Magnética , Osteossarcoma/diagnóstico por imagem , Osteossarcoma/patologia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Ósseas/patologia , Necrose/diagnóstico
2.
Abdom Radiol (NY) ; 49(1): 151-162, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37804424

RESUMO

OBJECTIVES: To develop an MRI radiomic nomogram capable of identifying muscle invasive bladder cancer (MIBC) patients with high-risk molecular characteristics related to poor 2-year disease-free survival (DFS). METHODS: We performed a retrospective analysis of DNA sequencing data, prognostic information, and radiomics features from 91 MIBC patients at stages T2-T4aN0M0 without history of immunotherapy. To identify risk stratification, we employed Cox regression based on TP53 mutation status and tumor mutational burden (TMB) level. Radiomics signatures were selected using the least absolute shrinkage and selection operator (LASSO) to construct a nomogram based on logistic regression for predicting the stratification in the training cohort. The predictive performance of the nomogram was assessed in the testing cohort using receiver operator curve (ROC), Hosmer-Lemeshow (HL) test, clinical impact curve (CIC), and decision curve analysis (DCA). RESULTS: Among 91 participants, the mean TMB value was 3.3 mut/Mb, with 60 participants having TP53 mutations. Patients with TP53 mutations and a below-average TMB value were identified as high risk and had a significantly poor 2-year DFS (hazard ratio = 4.36, 95% CI 1.82-10.44, P < 0.001). LASSO identified five radiomics signatures that correlated with the risk stratification. In the testing cohort, the nomogram achieved an area under the ROC curve of 0.909 (95% CI 0.789-0.991) and an accuracy of 0.889 (95% CI 0.708-0.977). CONCLUSION: The molecular risk stratification based on TP53 mutation status combined with TMB level is strongly associated with DFS in MIBC. Radiomics signatures can effectively predict this stratification and provide valuable information to clinical decision-making.


Assuntos
Neoplasias , Radiômica , Humanos , Intervalo Livre de Doença , Estudos Retrospectivos , Imageamento por Ressonância Magnética , Músculos
3.
Nano Lett ; 23(21): 10013-10020, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37856232

RESUMO

The realization of multiferroic materials offers the possibility of multifunctional electronic device design. However, the coupling between the multiferroicity and piezoelectricity in Janus materials is rarely reported. In this study, we propose a mechanism for manipulating valley physics by magnetization reversing and ferroelectric switching in multiferroic and piezoelectric material. The ferromagnetic VSiGeP4 monolayer exhibits a large valley polarization up to 100 meV, which can be effectively operated by reversing magnetization. Interestingly, the antiferromagnetic VSiGeP4 bilayers with AB and BA stacking configurations allow the coexistence of valley polarization and ferroelectricity, supporting the proposed strategy for manipulating valley physics via ferroelectric switching and interlayer sliding. In addition, the VSiGeP4 monolayer contains remarkable tunable piezoelectricity regulated by electron correlation U. This study proposes a feasible idea for regulating valley polarization and a general design idea for multifunctional devices with multiferroic and piezoelectric properties, facilitating the miniaturization and integration of nanodevices.

4.
BMC Med Imaging ; 23(1): 159, 2023 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-37845636

RESUMO

BACKGROUND: There is a paucity of research investigating the application of machine learning techniques for distinguishing between lipid-poor adrenal adenoma (LPA) and subclinical pheochromocytoma (sPHEO) based on radiomic features extracted from non-contrast and dynamic contrast-enhanced computed tomography (CT) scans of the abdomen. METHODS: We conducted a retrospective analysis of multiphase spiral CT scans, including non-contrast, arterial, venous, and delayed phases, as well as thin- and thick-thickness images from 134 patients with surgically and pathologically confirmed. A total of 52 patients with LPA and 44 patients with sPHEO were randomly assigned to training/testing sets in a 7:3 ratio. Additionally, a validation set was comprised of 22 LPA cases and 16 sPHEO cases from two other hospitals. We used 3D Slicer and PyRadiomics to segment tumors and extract radiomic features, respectively. We then applied T-test and least absolute shrinkage and selection operator (LASSO) to select features. Six binary classifiers, including K-nearest neighbor (KNN), logistic regression (LR), decision tree (DT), random forest (RF), support vector machine (SVM), and multi-layer perceptron (MLP), were employed to differentiate LPA from sPHEO. Receiver operating characteristic (ROC) curves and area under the curve (AUC) values were compared using DeLong's method. RESULTS: All six classifiers showed good diagnostic performance for each phase and slice thickness, as well as for the entire CT data, with AUC values ranging from 0.706 to 1. Non-contrast CT densities of LPA were significantly lower than those of sPHEO (P < 0.001). However, using the optimal threshold for non-contrast CT density, sensitivity was only 0.743, specificity 0.744, and AUC 0.828. Delayed phase CT density yielded a sensitivity of 0.971, specificity of 0.641, and AUC of 0.814. In radiomics, AUC values for the testing set using non-contrast CT images were: KNN 0.919, LR 0.979, DT 0.835, RF 0.967, SVM 0.979, and MLP 0.981. In the validation set, AUC values were: KNN 0.891, LR 0.974, DT 0.891, RF 0.964, SVM 0.949, and MLP 0.979. CONCLUSIONS: The machine learning model based on CT radiomics can accurately differentiate LPA from sPHEO, even using non-contrast CT data alone, making contrast-enhanced CT unnecessary for diagnosing LPA and sPHEO.


Assuntos
Adenoma , Neoplasias das Glândulas Suprarrenais , Feocromocitoma , Humanos , Adenoma/diagnóstico por imagem , Neoplasias das Glândulas Suprarrenais/diagnóstico por imagem , Lipídeos , Aprendizado de Máquina , Feocromocitoma/diagnóstico por imagem , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
5.
Nanoscale ; 15(24): 10458-10464, 2023 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-37309617

RESUMO

Two-dimensional photocatalytic materials with unique properties have been well-reported in recent decades. However, strategies for controlling the photocatalytic process are still ongoing. Herein, Janus X2PAs (X = Si, Ge and Sn) monolayers have been explored by first-principles calculations to meet this challenge. All strain-free X2PAs monolayers exhibit excellent photocatalytic properties with high carrier mobility (2.39 × 102-1.34 × 104 cm2 V-1 s-1), suitable band edge positions straddling the standard redox potential of water and large visible light absorption coefficients (up to 105 cm-1). Most importantly, a reaction switch effect is proposed for the first time towards controlling the microscopic photocatalytic process of water splitting on X2PAs monolayers through macroscopic mechanical strain. This effect renders the Janus X2PAs photocatalytic switches among the states of only oxygen evolution reaction, only hydrogen evolution reaction and the full redox reaction for controlled water splitting. This work not only provides a new avenue for designing highly tunable photocatalysts but also offers new physical insights into controlling the photocatalytic water-splitting reaction.


Assuntos
Excipientes , Hidrogênio , Oxigênio , Água
6.
Ying Yong Sheng Tai Xue Bao ; 34(5): 1203-1210, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37236936

RESUMO

To explore the adaptative strategies of single-veined plants along the environmental gradient, we collec-ted leaves of 57 Pinaceae species (including Abies, Larix, Pinus and Picea) from 48 sites along a latitudinal gradient (26°58'-35°33' N) on the eastern Qinghai-Tibet Plateau. By measuring three traits of leaf vein, including vein length per leaf area, vein diameter, and vein volume per unit leaf volume, we analyzed the trade-off between vein traits and their relationship with environmental changes. The results showed no significant difference in vein length per leaf area among different genera, but significant difference in vein diameter and vein volume per unit leaf volume. There was a positive correlation between vein diameter and vein volume per unit leaf volume for all genera. There was no significant correlation of vein length per leaf area with vein diameter and vein volume per unit leaf volume. With the increases of latitude, vein diameter and vein volume per unit leaf volume significantly decreased. In contrast, vein length per leaf area did not show a latitudinal trend. Mean annual temperature was the main factor driving the variation in vein diameter and vein volume per unit leaf volume. The relationships between vein length per leaf area and environmental factors were relatively weak. These results indicated that the single-veined Pinaceae plants have a special adaptative strategy to environmental changes through adjusting vein diameter and vein volume per unit leaf volume, which is quite different from complex vein structures such as reticular veins.


Assuntos
Pinaceae , Tibet , China , Plantas , Folhas de Planta
7.
Biomed Environ Sci ; 36(4): 334-342, 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37105908

RESUMO

Objective: The prevalence and related factors of serum anti-HCV in different regions and hospitals have not been studied extensively in China. We used routine screening data to determine the prevalence of HCV antibody in hospital patients, evaluate the epidemic trend of hepatitis C and formulate screening strategies. Methods: Patient information and HCV antibody testing results were collected from January 2017 to December 2019 in 77 HCV sentinel hospitals in China. Univariate and multivariate logistic regression was used to determine the characteristics and associations. Results: HCV antibody prevalence rates were distinct among patients in different departments, with a range of 0.33%-6.93%. Patients who were admitted to the liver disease-related departments (a OR = 10.76; 95% CI, 10.27-11.28), Internal Medicine (a OR = 2.87; 95% CI, 2.75-3.00), and Department of Surgery (a OR = 1.95; 95% CI, 1.87-2.04), were more likely to be tested for HCV antibody positive. HCV antibody prevalence was associated with patients aged 45 years and older (a OR = 2.74; 95% CI, 2.69-2.80), testing in infetious disease hospitals (a OR = 2.33; 95% CI, 2.26-2.40) and secondary hospitals (a OR = 1.72; 95% CI, 1.69-1.75). Patients in sentinel hospitals of the Northeast (a OR = 12.75; 95% CI, 12.40-13.11), the Central (a OR = 1.65; 95% CI, 1.61-1.70), and the West (a OR = 1.78; 95% CI, 1.73-1.83) China had higher HCV prevalence than those who were in the Eastern coastal area. Conclusion: Those who were over 45 years old and saw doctors for liver diseases, and invasive diagnosis and treatment should be referred to HCV antibody testing.


Assuntos
Anticorpos Anti-Hepatite C , Hepatite C , Humanos , Pessoa de Meia-Idade , China/epidemiologia , Hepacivirus , Hepatite C/epidemiologia , Anticorpos Anti-Hepatite C/sangue , Hospitais , Prevalência , Fatores de Risco
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 296: 122648, 2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-36966729

RESUMO

The deleterious toxicity of Hg2+ on ecological and biological system makes it crucial for the precise monitoring of Hg2+. Herein, we prepared a novel "turn-on" chemosensor N'-(4-(methylthio)butan-2-ylidene) rhodamine B hydrazide (denoted as MTRH) by a simple two-step reaction. MTRH exhibited an ultra-low detection limit (LOD) in fluorescence measurement of Hg2+ in pure aqueous media, which was estimated to be 1.3 × 10-9 mol·L-1. Moreover, the proposed chemosensor holds the ability of visualizing Hg2+ by the distinct color change of the solution. The corresponding recognition mechanism was investigated by Job's plots, mass spectrometry and DFT calculation analysis. Importantly, the characteristics such as high sensitivity, low cytotoxicity and good biocompatibility of MTRH exhibited in the application of detecting Hg2+ in real water sample and bioimaging of intracellular Hg2+ prove that MTRH is a promising tool to evaluate the levels of Hg2+ in complex biological systems.


Assuntos
Mercúrio , Mercúrio/análise , Água , Espectrometria de Massas , Corantes Fluorescentes/química , Espectrometria de Fluorescência/métodos
9.
ACS Infect Dis ; 9(3): 593-608, 2023 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-36808986

RESUMO

The resuscitation of dormant Mycobacterium tuberculosis is an important cause of adult tuberculosis (TB) transmission. According to the interaction mechanism between M. tuberculosis and the host, the latency antigen Rv0572c and region of difference 9 (RD9) antigen Rv3621c were selected in this study to prepare the fusion protein DR2. Stimulating clinically diagnosed active tuberculosis infections (i.e., TB patients), latent tuberculosis infections, and healthy controls confirmed that T lymphocytes could recognize DR2 protein in the peripheral blood of TB-infected individuals more than subcomponent protein. The DR2 protein was then emulsified in the liposome adjuvant dimethyl dioctadecyl ammonium bromide, and imiquimod (DIMQ) was administered to C57BL/6 mice immunized with Bacillus Calmette-Guérin (BCG) vaccine to evaluate their immunogenicity. Studies have shown that DR2/DIMQ, a booster vaccine for BCG primary immunization, can elicit robust CD4+ Th1 cell immune response and predominant IFN-γ+ CD4+ effector memory T cells (TEM) subsets. Furthermore, the serum antibody level and the expression of related cytokines increased significantly with the extension of immunization time, with IL2+, CD4+, or CD8+ central memory T cells (TCM) subsets predominant in the long term. This immunization strategy showed matched prophylactic protective efficacy by performing in vitro challenge experiment. This result provides robust evidence that the novel subunit vaccine prepared by fusion protein DR2 combined with liposomal adjuvant DIMQ is a promising TB vaccine candidate for further preclinical trials as a booster vaccine for BCG.


Assuntos
Mycobacterium bovis , Mycobacterium tuberculosis , Tuberculose , Animais , Camundongos , Vacina BCG , Lipossomos , Antígenos de Bactérias/genética , Camundongos Endogâmicos C57BL , Tuberculose/prevenção & controle , Adjuvantes Imunológicos , Imunização Secundária
10.
J Phys Chem Lett ; 13(41): 9654-9663, 2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36214516

RESUMO

Development of piezoelectric materials is limited partly due to the incompleteness of internal mechanism and the lack of vertical piezoelectricity. Herein, we theoretically identify the stable MoTO (T = S, Se, or Te) monolayers and bilayers. When two elements are given but another element can be changed, the larger the electronegativity difference ratio Rratio is, the stronger the piezoelectricity will be. Vertical piezoelectric coefficient d33 of the MoTeO bilayer reaches 38.907 pm/V, which is 12 times larger than that of the bulk GaN. The "active asymmetric electron-transfer" strategy mainly contributes to the spontaneous remarkable piezoelectricity of MoTO. Importantly, we proposed the new method for calculating the piezoelectric coefficients of two-dimensional (2D) materials, which corresponds to the fact that 2D materials have a certain thickness. This study not only provides novel extraordinary candidates for energy conversion and touch-sensor nanodevices but also promotes a deeper understanding of piezoelectricity of 2D materials.

11.
Plant Physiol Biochem ; 192: 50-56, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36206706

RESUMO

When a plant is exposed to heterogeneous light, the photosynthesis of unshaded leaves is often stimulated to compensate for the decline in photosynthesis of shaded leaves, i.e., photosynthetic compensation. However, a decline of photosynthesis in unshaded leaves, which means an impairment of photosynthetic compensation, has also been widely reported. Herein, two cultivars of maize (Zea mays L.), 'Rongyu1210' (RY) and 'Zhongdan808' (ZD), were studied comparatively. Both cultivars performed evident photosynthetic compensation under heterogeneous light (HL) as the light phase begins (8:30 a.m.). However, as the light phase continues (10:30 a.m.), an impairment of photosynthetic compensation took place in HL-treated ZD, but not in HL-treated RY. For both cultivars, nitrogen content of unshaded leaves was higher under HL, indicating a preferential nitrogen distribution towards unshaded leaves. This is related to the photosynthetic compensation but not the cause of the impairment. In addition, no obvious difference was found in the response of photosynthates (sucrose and starch) to HL between cultivars at 8:30 a.m. However, at 10:30 a.m., the content of photosynthates decreased significantly in unshaded leaves of HL-treated RY, along with increased abundances of both sucrose transporters (SUTs) and H+-ATPase (EC 7.1.2.1). In contrast, it increased along with decreased abundances of SUTs and H+-ATPase in HL-treated ZD. These results suggest that the photosynthetic compensation is impaired when photosynthates export of unshaded leaves is restricted. This suggestion is further confirmed by the results of 13C labeling and dry weight detection on young leaves as 'sink'.

12.
Sci Rep ; 12(1): 16807, 2022 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-36207476

RESUMO

Evidence for an association between the amount of particulate matter (PM) in the atmosphere and vitamin D status of pregnant women is limited. We aimed to examine the independent association between PM and maternal levels of serum 25-hydroxyvitamin D (25OHD) during the second trimester and to explore possible modifications to the association by meteorological factors. 27,768 pregnant women presenting for prenatal examination who were tested for serum 25OHD concentration during the second trimester between January 1, 2016, and December 31, 2020, were included in this retrospective analysis. Exposure to PM was evaluated based on daily average PM with an aerodynamic diameter of ≤ 2.5 µm (PM2.5) and PM with an aerodynamic diameter of ≤ 10 µm (PM10). Corresponding meteorological data for daily average atmospheric temperature, atmospheric pressure, relative humidity, sunshine duration, and wind speed were collected. The maximum cumulative effects of PM2.5 occurred at lag 45 days, and the maximum cumulative effects of PM10 occurred at lag 60 days. In crude models, 45-day moving daily average PM2.5 concentrations were negatively associated with 25OHD levels (ß, - 0.20; 95% CI - 0.21 to - 0.19), as were 60-day moving daily average PM10 concentrations (ß, - 0.14; 95% CI - 0.15 to - 0.14). After adjusting for temporal and meteorological factors, the effect values were drastically reduced (adjusted ß of PM2.5, - 0.032; 95% CI - 0.046 to - 0.018; adjusted ß of PM10, - 0.039; 95% CI - 0.049 to - 0.028). Our study showed there was a small, independent, negative association between PM in the atmosphere and maternal serum 25OHD levels during the second trimester of pregnancy after adjusting for temporal and/or meteorological factors, which indicates that PM may have a limited influence on maternal serum 25OHD levels. Besides taking vitamin D supplements, pregnant women should keep participating in outdoor activities while taking PM protection measures to improve their vitamin D levels when PM levels are high in winter and spring.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Colestanos , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Poluição do Ar/análise , China , Feminino , Humanos , Conceitos Meteorológicos , Material Particulado/análise , Gravidez , Estudos Retrospectivos , Estações do Ano , Vitamina D/análise , Vitaminas/análise
13.
Phys Chem Chem Phys ; 24(39): 24264-24270, 2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36172737

RESUMO

The oxidation of methane to a high-value-added chemical, methanol, is a major challenge in catalysis, requiring high energy input to overcome the CH3-H bond activation energy barrier. Based on density functional theory (DFT) calculations, methane oxidation to methanol is catalyzed by hetero-diatomic catalysts (CuZn-NG) with different coordination spheres (CSs). Valence band maximum (VBM), atomic charge and d-band center are selected as analysis methods for the pathway selection and activity of catalysis. The VBM plays a vital role in the catalytic pathway selection, CuZn-NG catalyzes the direct conversion of methane into methanol without side reactions. Alarmingly, the most important reaction step, CH3-H bond activation, is a spontaneously exothermic reaction (releasing 0.06 eV) with CuZn-NPAG as the catalyst, in contrast to most other endothermic reactions in the same activation. By analyzing the atomic charge of the Cu center and O atom, the special electronic phenomenon for this important step is summarized as the "bow-release effect". The CS affects the electronic properties of the active center and further affects the methane oxidation activity. This work provides a useful guide to understand the catalytic selectivity and activity of hetero-diatomic catalysts.

14.
World J Clin Cases ; 10(13): 4145-4152, 2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35665121

RESUMO

BACKGROUND: Primitive neuroectodermal tumor (PNET), especially located in the prostate, is a rare tumor that mainly occurs in young men. Bladder or rectum invasion and distant metastasis are strongly associated with a poor prognosis. Combination therapy, including radical surgery, adjuvant chemotherapy, and radiotherapy, is available. We present a case of prostatic PNET and a review of 17 cases identified in the literature. CASE SUMMARY: A 58-year-old man was admitted complaining of dysuria for 2 years. Computed tomography and magnetic resonance imaging showed a large cystic-solid mass in the pelvic cavity compressing the surrounding bladder and rectum. The mass was iso- to hyperintense on T1-weighted imaging (WI) and heterogeneously hyperintense on T2WI. Cystic degeneration and necrosis were seen in the tumor, and solid tissues within the mass enhanced on contrast-enhanced scan. The patient underwent robot-assisted laparoscopic pelvic tumor resection. Histologically, the presence of many small round cells that were positive for expression of CD99, vimentin, and synaptophysin established the diagnosis of PNET in the prostate after surgery. The patient underwent adjuvant chemotherapy. During 34 mo of follow-up, the patient had no signs or symptoms of recurrence or residual disease. CONCLUSION: We present the case of the oldest prostatic PNET patient, who has a good prognosis. This illustrates how older men with prostatic PNET may also benefit from the combination therapy, like younger adults, and achieve a long-term survival. As always, PNET should be considered in the differential diagnosis of aggressive prostatic tumors in young men.

15.
Front Psychol ; 13: 871936, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35712153

RESUMO

There are many factors affecting decisions to persistent participation in sports and various approaches have been used to frame these antecedents. The aim of this paper was to systematically review and quantify the primary factors of persistent participation and to assess their respective strengths of association with persistent participation in youth sport. Adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyzes (PRISMA) guidelines, a comprehensive search was implemented on 31st December 2021 in five databases and meta-analytic procedures were applied to data from studies meeting inclusion criteria. The results revealed that sports enjoyment (meta r = 0.45, 95%CI [0.42, 0.49]) was highly correlated with persistent intention, while persistent intention (SMD = 1.13, 95%CI [0.70, 1.56]) was highly correlated with persistent behavior. In addition, parental support, coach support, peer support, basic psychological needs and sports competence were the primary factors associated with persistent intention and persistent behavior, respectively. This study identified the key factors related to persistent participation and provide a complete understanding of children and adolescents' decisions to continue their participation in organized sports. Referring to the key factors, it can provide information for sports clubs and policy makers to develop strategies to increase youth participation in organized sport. Systematic Review Registration: PROSPERO, identifier: CRD42021229397.

16.
Ying Yong Sheng Tai Xue Bao ; 33(12): 3328-3336, 2022 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-36601838

RESUMO

To provide theoretical support the full use of water and fertilizer resources for wheat, we explored the effects of irrigation on wheat yield, plant and soil nutrient distribution during flowering period and its relationship with root characteristics. We set up two treatments by using the 2 m deep soil column cultivation method with irrigation during flowering (T1) and no irrigation during flowering (T2), with the drought-resistant and high-yield cultivar Luomai 28 (LM28) and the high photosynthetic efficiency cultivar Bainong 207 (BN207) as materials. We measured contents of nitrogen, phosphorus and potassium in plants and soils, as well as the characteristics of soil roots. The results showed that ammonium, available phosphorus, and available potassium were mainly distributed in 0-80 cm soil layer, and that nitrate was mainly distributed in soil layer below 80 cm during wheat harvest. Irrigation at anthesis stage promoted wheat to absorb ammonium, available phosphorus and available potassium from the upper layer of soil and nitrate nitrogen from the lower layer but did not aggravate the deep leaching of nitrate. The root of wheat mainly concentrated in 0-60 cm soil layer and decreased with increasing soil depth. Dry matter accumulation, total nitrogen and total phosphorus were mainly distributed in wheat grains at maturity, while total potassium was mainly distributed in stems. Irrigation at anthesis stage significantly increased the 100-grain weight of wheat, and consequently the yield. Root morphology was negatively correlated with soil nitrate in 0-40 cm soil layer, positively correlated with soil ammonium in 80-100 cm soil layer and soil available phosphorus in 0-100 cm soil layer. Irrigation at anthesis stage promoted the full absorption of soil nutrients by roots at late filling stage, delayed the senescence of flag leaves after flowering, prolonged the functional period of transporting nutrients from vegetative organs to reproductive organs, leading nutrients in vegetative organs more fully transported to grains, increasing grain weight and yield.


Assuntos
Irrigação Agrícola , Solo , Irrigação Agrícola/métodos , Triticum , Nitratos/análise , Biomassa , Nitrogênio/análise , Água , Grão Comestível/química
17.
Nanoscale ; 14(1): 187-195, 2021 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-34904996

RESUMO

In alkaline solution, the electrocatalytic oxygen evolution reaction (OER) of dual transition metal atom (2TM) nitrogen-decorated graphene as a double-atom catalyst (DAC) has received special attention. Here, using density functional theory (DFT) calculations, the OER electrocatalysis of 2TM-pyridine/amino-nitrogen-decorated graphene (2TM-NPAG and 2TM-NPG. 2TM represents FeCo, FeNi, Conti) is studied. The electrocatalytic OER mechanism is that 2TM-NPG acts as the pre-catalyst, while the real catalysts are 2TM-NPAG and 2TM-NPG-O. In particular, CoNi-NPAG and CoNi-NPG-O exhibit higher OER activity compared to state-of-the-art RuO2 at pH = 14. It is confirmed that the potential-determining step is also the rate-determining step. Amino-nitrogen is the main accepter of electrons from CoNi atoms and pyridine-nitrogen is the main acceptor of electrons from nearby C atoms. The role of different N coordination continues to influence the entire electrocatalytic OER process of CoNi-NG. Simultaneously, the overpotential of CoNi-NG is in a volcano-shaped relationship with the electronic properties (oxidation state or d-band center) of the catalytic site of Co. Moreover, CoNi-NPAG and CoNi-NPG-O are the closest to the center of the OER overpotential (a function of the d-band center and oxidation state) contour plot, implying that they exhibit the best catalytic activity among all the CoNi-NG materials. The optimal electronic properties of CoNi-NPAG and CoNi-NPG-O contribute towards their excellent OER performance, and provide a new breakthrough in developing high-performance DACs.

18.
Dose Response ; 19(4): 15593258211039931, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34658683

RESUMO

OBJECTIVE: To study the effects of adaptive response in A549 cells induced by low-dose radiation and the miRNAs expression. METHODS: A549 cells were irradiated with 50 mGy and 200 mGy initial doses, respectively, and then irradiated with a challenge dose 20 Gy at 6 hours interval. The biological effects and miRNA expression were detected. RESULTS: The apoptosis rates of 50 mGy-20 Gy and 200 mGy-20 Gy groups were significantly lower than that of only 20 Gy irradiation group (P < .05). The percentage of G2/M phase cells of 50 mGy-20 Gy and 200 mGy-20 Gy groups was significantly decreased relative to the 20 Gy group (P < .05). One miRNA (mir-3662) was upregulated and 15 miRNAs (mir-185, mir-1908, mir-307, mir-182, mir-92a, mir-582, mi-r501, mir138-5p, mir-1260, mir-484, mir-378d, mir-193b, mir-127-3p, mir-1303, and mir-654-5p) were downregulated both in 50 mGy-20 Gy and 200 mGy-20 Gy groups than that of the 20 Gy group. Go and KEGG enrichment analysis showed that the target genes were significantly enriched in cell communication regulation, metabolic process, enzyme binding, and catalytic activity signaling pathways. CONCLUSION: Low-dose X-ray of 50 mGy and 200 mGy radiation can induce adaptive apoptosis response prior to 20 Gy in A549 cells. Sixteen differently expressed miRNAs may play important roles in the adaptive effect of low-dose radiation.

19.
Ying Yong Sheng Tai Xue Bao ; 32(10): 3415-3427, 2021 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-34676702

RESUMO

Daxing'an Mountains is one of regions in China with the most significant climate change. Larix gmelinii and Pinus sylvestris var. mongolica are the most important species in this area. The study of their radial growth response to climate change would provide a scientific basis for predicting the dynamics of boreal forests under climate change. A total of 451 tree-ring cores of L. gmelinii and P. sylvestris var. mongolica were collected from six sites in the Daxing'an region, and 12 standard chronologies were established. We compared the tree growth trend since 1900, and analyzed their response to the climate factor in each site using Pearson correlation analysis. Effects of temperature and precipitation on the annual radial growth of L. gmelinii and P. sylvestris var. mongolica were investigated by linear mixed models. The time stability of the relationship between two species growth-climate was compared by moving correlation. The results showed that the radial growth of L. gmelinii was negatively correlated with mean temperature in March and positively correlated with precipitation in the previous winter and July of current year. The radial growth of P. sylvestris var. mongolica was positively correlated with temperature in August and precipitation in the growing season (from May to September) of current year. Snow in winter played an important role in promoting the radial growth of L. gmelinii, whereas precipitation in summer limited the radial growth of P. sylvestris var. mongolica. The responses of L. gmelinii and P. sylvestris var. mongolica to climate change were significantly different, which affected tree growth, species composition, and spatial distribution in the boreal forests.


Assuntos
Larix , Pinus sylvestris , China , Mudança Climática , Árvores
20.
Ying Yong Sheng Tai Xue Bao ; 32(10): 3428-3436, 2021 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-34676703

RESUMO

With global climate warming, warming and drying in Northeast China are becoming more and more serious. To understand the effects of drought on the radial growth of Fraxinus mandshurica at different slope positions in Xiaoxing'an Mountains, we analyzed the responses of xylem anatomical characteristics of F. mandshurica to moisture change at different slope positions by wood anatomi-cal method. The results showed that F. mandshurica on the upper and lower slope positions were the same in the changes of xylem anatomical parameters. The abundance of vessels showed a linear distribution, the maximum vessel area and total vessel area showed a logarithmic distribution, while the average vessel area showed a partial normal distribution. There were significant differences in many anatomical parameters among different slope positions. The abundance and area of vessels on the lower slope positions were larger than those on the upper slope positions. Most of the anatomical parameters were significantly positively correlated with daily accumulated temperature, though there were some differences between them. The total vessel area of F. mandshurica on the upper slope positions was positively correlated with the daily mean temperature, while the number and total area of vessels were positively correlated with the relative humidity. The correlation on the upper slope positions was stronger than that on the lower slope positions. The minimum vessel area was negatively correlated with daily accumulated temperature and relative humidity on the upper slope positions, while the total vessel area was positively correlated with relative humidity on lower slope positions. The warming and drying climate would reduce the area and number of vessels in F. mandshurica, but would not affect the distribution of vessels, while the distribution of vessels on the upper and lower slope positions was generally the same. The current climate warming and drying do not limit but promote the radial growth of F. mandshurica.


Assuntos
Fraxinus , Clima , Secas , Temperatura , Xilema
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