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1.
BMC Plant Biol ; 24(1): 184, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38475704

RESUMEN

Using the blueberry cultivar "Powderblue" after pollination, fruits at different developmental stages were collected for study. The transverse and longitudinal diameters, individual fruit weight, and fruit water content were measured during their development. Employing tissue sectioning and microscopy techniques, we systematically studied the morphological features and anatomical structures of the fruits and seeds at various developmental stages, aiming to elucidate the cytological patterns during blueberry fruit development. The results of our study revealed that the "Powderblue" blueberry fruit growth and development followed a double "S" curve. Mature "Powderblue" blueberries were blue-black in color, elliptical in shape, with five locules, an inferior ovary, and an average fruit weight of 1.73 ± 0.17 g, and a moisture content of 78.865 ± 0.9%. Blueberry fruit flesh cells were densely arranged with no apparent intercellular spaces, and mesocarp cells accounted for 52.06 ± 7.4% of fruit cells. In the early fruit development stages, the fruit flesh cells were rapidly dividing, significantly increasing in number but without greatly affecting the fruit's morphological characteristics. During the later stages of fruit development, the expansion of the fruit flesh cells became prominent, resulting in a noticeable increase in the fruit's dimensions. Except for the epidermal cells, cells in all fruit tissues showed varying degrees of rupture as fruit development progressed, with the extent of cell rupture increasing, becoming increasingly apparent as the fruit gradually softened. Additionally, numerous brachysclereids (stone cells) appeared in the fruit flesh cells. Stone cells are mostly present individually in the fruit flesh tissue, while in the placental tissue, they often group together. The "Powderblue" blueberry seeds were light brown, 4.13 ± 0.42 mm long, 2.2 ± 0.14 mm wide, with each fruit containing 50-60 seeds. The "Powderblue" seeds mainly consisted of the seed coat, endosperm, and embryo. The embryo was located at the chalazal end in the center of the endosperm and was spatially separated. The endosperm, occupying the vast majority of the seed volume, comprised both the chalazal and outer endosperm, and the endosperm developed and matured before the embryo. As the seed developed, the seed coat was gradually lignified and consisted of palisade-like stone cells externally and epidermal layer cells internally.


Asunto(s)
Arándanos Azules (Planta) , Frutas , Embarazo , Femenino , Humanos , Arándanos Azules (Planta)/química , Placenta , Semillas , Endospermo
2.
Angew Chem Int Ed Engl ; 62(22): e202301483, 2023 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-36890120

RESUMEN

Efficient molecular oxygen activation (MOA) is the key to environmentally friendly catalytic oxidation reactions. In the last decade, single-atomic-site catalysts (SASCs) with nearly 100 % atomic utilization and unique electronic structure have been widely investigated for MOA. However, the single active site makes the activation effect unsatisfactory and difficult to deal with complex catalytic reactions. Recently, dual-atomic-site catalysts (DASCs) have provided a new idea for the effective activation of molecular oxygen (O2 ) due to more diverse active sites and synergetic interactions among adjacent atoms. In this review, we systematically summarized the recent research progress of DASCs for MOA in heterogeneous thermo- and electrocatalysis. Finally, we look forward to the challenges and application prospects in the construction of DASCs for MOA.

3.
Clin Exp Hypertens ; 41(8): 702-707, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30497286

RESUMEN

OBJECTIVE: Some studies have reported that both serum cystatin C (Cys C) and dyslipidemia are independently associated with hypertension. However, the combined effect of the two factors is still unknown. The present study was aimed at investigating the effect of Cys C combined with dyslipidemia on hypertension in a large health check-up population in China. METHODS: A total of 203 233 health check-up subjects from January 2011 to July 2016 were recruited into this cross-sectional study. A multivariate logistic regression model was used to evaluate the combined effect of Cys C and dyslipidemia on hypertension.RESULTS: In univariate analysis, Cys C, high-density lipoprotein cholesterol, low-density lipoprotein, total cholesterol, and triglycerides were independently correlated with hypertension (p < 0.001). A concentration-dependent combined effect of serum Cys C and dyslipidemia on hypertension was observed in multivariate regression analysis. When compared with Cys C of <0.82 mg/L, the risk of hypertension in Cys C of <0.82 mg/L with dyslipidemia, Cys C  of 0.82-0.94 mg/L with dyslipidemia, Cys C  of 0.94-1.08 mg/L with dyslipidemia, and Cys C  of ≥1.08 mg/L with dyslipidemia was increased 1.946 (95% confidence interval [CI]: 1.827-2.074), 1.973 (95% CI: 1.864-2.088), 2.047 (95% CI: 1.941-2.158), and 2.038 (95% CI: 1.937-2.143) folds, respectively, after adjustment.CONCLUSION: There was an association between hypertension and the combined effect of Cys C with dyslipidemia.


Asunto(s)
Cistatina C/sangre , Dislipidemias/sangre , Hipertensión/sangre , Vigilancia de la Población , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , China/epidemiología , HDL-Colesterol/sangre , Estudios Transversales , Dislipidemias/epidemiología , Femenino , Humanos , Hipertensión/epidemiología , Hipertensión/fisiopatología , Incidencia , Masculino , Persona de Mediana Edad , Adulto Joven
4.
Sci Rep ; 14(1): 4551, 2024 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-38402302

RESUMEN

The proposed study presents an enhanced combination weighting cloud model for accurate assessment of coal and gas outburst risks. Firstly, a comprehensive evaluation index system for coal and gas outburst risks is established, consisting of primary indicators such as coal rock properties and secondary indicators including 13 factors. Secondly, the improved Analytic Hierarchy Process (IAHP) based on the 3-scale method and the improved CRITIC based on indicator correlation weight determination method are employed to determine subjective and objective weights of evaluation indicators respectively. Additionally, the Lagrange multiplier method is introduced to fuse these weights in order to obtain optimal weights. Subsequently, a prominent danger assessment model is developed based on cloud theory. Finally, using a mine in Hebei Province as an example, the results obtained from IAHP combined with improved CRITIC weighting method are compared with those from traditional AHP method and AHP-CRITIC combination weighting method. The findings demonstrate that among all methods considered, IAHP combined with improved CRITIC exhibits superior performance in terms of distribution expectation Ex, entropy value En, and super entropy He within cloud digital features; thus indicating that the risk level of coal and gas outbursts in this particular mine can be classified as general risk. These evaluation results align well with actual observations thereby validating the effectiveness of this approach. Consequently, this constructed model enables rapid yet accurate determination of coal and gas outburst risks within mines.

5.
J Hazard Mater ; 459: 132120, 2023 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-37487333

RESUMEN

Photocatalytic activation of persulfate has exhibited tremendous potential in water purification because of its green and environmentally friendly process. However, this process often exhibits low activation efficiencies and difficult recovery of the photocatalyst. Herein, schorl-supported nano-TiO2 composite photocatalysts (S/TiO2) were prepared by a mechanical grinding method for efficient activation of potassium monopersulfate (PMS). The anatase TiO2 nanoparticles with particle size of approximately 30 nm was uniformly loaded on the surface of schorl via forming Si-O-Ti bonds. The S/TiO2 assisted with PMS (S/TiO2-PMS) exhibited remarkable degradation performance and stability. In this system (S/TiO2-PMS), the C/C0 value of phenol solution (10 ppm) were decreased to 0.070 and 0 after 30 min and 90 min of irradiation, where the degradation extent were 93.0% and 100% respectively. The rate of phenol degradation with S/TiO2-PMS was 12.6 times that seen with TiO2-PMS. The oxidation active species were holes and SO4•- in S/TiO2-PMS system subjected to simulated sunlight. It was demonstrated that the polarization electric field of the schorl enhanced the separation efficiency of the photoinduced electrons and holes for improving the performance of the S/TiO2-PMS. On the other hand, the transformations of Fe3+ and Fe2+ on the schorl surface further promotes the activation of PMS. This work provides a new choice for designing TiO2-based photocatalytic persulfate activation system targeting the field of advanced oxidation water treatment.

6.
Micromachines (Basel) ; 13(7)2022 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-35888928

RESUMEN

The rectangular gyrotron traveling wave tube (gyro-TWT) with a large aspect ratio (α) has the potential to achieve megawatt-class output power. As an essential component of gyro-TWT, a novel overmoded Ka-band mode converter with an α of 6.19 is designed, analyzed, and cold tested in this paper. Based on the magnetic dipole moment theory, the rectangular overmoded TE01 mode is excited via the rectangular fundamental TE10 mode. The cutoff waveguide is applied to prevent electromagnetic wave transport to the magnetron injection gun (MIG) region and also guarantee higher power electron beam transportation. Simulations predict an operation bandwidth higher than 4 GHz and greater than 99.8% mode purity between 33-37 GHz. To verify this design, the mode converter is manufactured and cold tested. The back-to-back measurement results exhibit a good agreement with the simulation. With similar topologies, the rectangular overmoded TE01 mode can be excited in a different α.

7.
J Am Soc Hypertens ; 12(5): 327-334, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29606529

RESUMEN

This study was aimed at investigating the relationship between red blood cell distribution width (RDW) and hypertension in a large health check up population in China. A population of 302,527 subjects from Wuhu was enrolled in this cross-sectional health check up study between 2011 and 2016. They consisted of 126,369 women (41.78%) and 176,158 men (58.23%) with mean age of 46.9 ± 13.4 and 48.1 ± 13.7 years, respectively. The investigations included information on demographic characteristics, physical examination, and laboratory testing. Inverted U-shape relationships were observed between RDW and hypertension with peak RDW values of 14.2 (women) and 15.2 (men). After stratification by sex and adjusted with body mass index, age, white blood cells, and high-density lipoprotein cholesterol, inverted U-shape relationships were also established between RDW and hypertension, systolic blood pressure, and diastolic blood pressure, with peak RDW of 14.2, 14.5, 14.5 in women and 14.2, 16.0, 14.5 in men. Inverted U-shape relationship exists between RDW and hypertension, systolic blood pressure, and diastolic blood pressure among the Chinese health check up population studied.

8.
BMJ Open ; 8(4): e020899, 2018 04 10.
Artículo en Inglés | MEDLINE | ID: mdl-29643166

RESUMEN

OBJECTIVE: This study was aimed at investigating the relationship between neuron-specific enolase (NSE) and components of metabolic syndrome (MS). DESIGN: Cross-sectional study. SETTING: Chinese health check-up population. PARTICIPANTS: 40 684 health check-up people were enrolled in this study from year 2014 to 2016. MAIN OUTCOME MEASURES: OR and coefficient for MS. RESULTS: The percentage of abnormal NSE and MS was 26.85% and 8.85%, respectively. There were significant differences in sex, body mass index, drinking habit, triglycerides (TGs), high-density lipoprotein cholesterol (HDL-C), blood pressure and MS between low-NSE and high-NSE groups. In logistic regression analysis, elevated NSE was present in MS, higher body mass index, hypertriglyceridaemia, hypertension and low-HDL groups. Stepwise linear analysis showed a negative correlation between NSE and fasting blood glucose (FBG) (<6.0 mmol/L), and a positive correlation between NSE and TGs (<20 mmol/L), systolic blood pressure (75-200 mm Hg), HDL-C (0.75-2.50 mmol/L), diastolic blood pressure (<70 mm Hg) and FBG (6.00-20.00 mmol/L). Furthermore, MS was positively correlated with NSE within the range of 2.00-7.50 ng/mL, but had a negative correlation with NSE within the range of 7.50-23.00 ng/mL. CONCLUSION: There are associations between NSE with MS and its components. The result suggests that NSE may be a potential predictor of MS. Further research could be conducted in discussing the potential mechanism involved.


Asunto(s)
HDL-Colesterol , Síndrome Metabólico , Fosfopiruvato Hidratasa , Adulto , Anciano , Glucemia , Índice de Masa Corporal , China , HDL-Colesterol/sangre , Estudios Transversales , Femenino , Humanos , Masculino , Síndrome Metabólico/sangre , Persona de Mediana Edad , Fosfopiruvato Hidratasa/sangre , Factores de Riesgo , Triglicéridos
9.
Int J Environ Res Public Health ; 12(11): 14275-84, 2015 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-26569275

RESUMEN

BACKGROUND: The carotid artery plaque score (PS) is an independent predictor of Coronary Heart Disease (CHD). This study aims to evaluate the combination of PS and carotid hemodynamics to predict CHD. METHODS: A total of 476 patients who underwent carotid ultrasonography and coronary angiography were divided into two groups depending on the presence of CHD. PS, carotid intima-media thickness, and carotid blood flow were measured. Receiver operating characteristic curve analysis was performed to establish the best prediction model for CHD presence. RESULTS: Age, sex, carotid intima-media thickness of internal carotid artery and carotid bifurcation, PS, peak systolic velocity (PSA) of right internal carotid artery (RICA), and most resistance index data were significantly related with the presence of CHD. The area under the curve for a collective model, which included factors of the PS, carotid hemodynamics and age, was significantly higher than the other model. Age, PS, and PSA of RICA were significant contributors for predicting CHD presence. CONCLUSIONS: The model of PS and PSA of RICA has greater predictive value for CHD than PS alone. Adding age to PS and PSA of RICA further improves predictive value over PS alone.


Asunto(s)
Estenosis Carotídea/diagnóstico por imagen , Estenosis Carotídea/diagnóstico , Enfermedad de la Arteria Coronaria/fisiopatología , Hemodinámica , Factores de Edad , Anciano , Anciano de 80 o más Años , Velocidad del Flujo Sanguíneo , Grosor Intima-Media Carotídeo , China , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Curva ROC , Factores de Riesgo , Factores Sexuales
10.
Rev Sci Instrum ; 84(11): 114702, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24289420

RESUMEN

To verify the performance of high power waveguide transmission devices such as the miter bend, the waveguide taper, and the quasi-optical mode converter by the low power measurement, a TE01 mode generator, converts the rectangular waveguide TE10 mode into the cylindrical waveguide TE01 mode, for Ka-band is designed, fabricated, and measured. The proposed generator consists of a TE10 to TE20 rectangular waveguide mode converter and a rectangular TE20 to circular TE01 mode converter. The converting process in each section is analyzed and the working principles are discussed. Two prototypes are built and tested. The back-to-back transmission measured results agree well with the numerical calculations. The measured optimum transmissions are 97% with a 1-dB bandwidth from 29.2 GHz to 31.6 GHz. The angle-independent transmissions demonstrate high mode purity and the presence of TE01 mode confirmed by the far-field measurement. The proposed mode generator features high conversion efficiency, high mode purity, and moderate broad bandwidth.

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