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1.
Front Plant Sci ; 14: 1083665, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37332706

RESUMEN

Wheat grain quality is equivalent to grain yield in terms of ensuring food security under climate change but has received less attention. Identifying critical meteorological conditions in key phenological periods to account for the variability in grain protein content (GPC) can provide insight into linkages between climate change and wheat quality. The wheat GPC data from different counties of Hebei Province, China during 2006-2018 and corresponding observational meteorological data were used in our study. Through a fitted gradient boosting decision tree model, latitude of the study area, accumulated sunlight hours during the growth season, accumulated temperature and averaged relative humidity from filling to maturity were suggested as the most relevant influencing variables. The relationship between GPC and latitude was distinguished between areas north and south of 38.0° N. GPC decreased with the increasing latitude in areas south of 38.0° N, where at least accumulated temperatures of 515°C from filling to maturity were preferred to maintain high GPC. Besides, averaged relative humidity during the same phenological period exceeding 59% could generate an extra benefit to GPC here. However, GPC increased with increasing latitude in areas north of 38.0° N and was mainly attributed to more than 1500 sunlight hours during the growth season. Our findings that different meteorological factors played a major role in deciding regional wheat quality provided a scientific basis for adopting better regional planning and developing adaptive strategies to minimize climate impacts.

2.
Adv Mater ; 35(28): e2301874, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37026437

RESUMEN

Amorphous polymers with ultralong room-temperature phosphorescence (RTP) are highly promising for various applications. Particularly, polymer-based RTP materials with multiple functions such as color-tunability or stimulus-response are highly desirable for multilevel anti-counterfeiting but are rarely reported. Herein, a facile strategy is presented to achieve a series of polymer-based RTP materials with ultralong lifetime, multicolor afterglow, and reversible response to UV irradiation by simply embedding pyridine-substituted triphenylamine derivatives into the polymer matrix poly(vinyl alcohol) (PVA) and poly(methyl methacrylate) (PMMA), respectively. Notably, the pyridine group with the capabilities of promoting intersystem crossing and forming hydrogen-bonding interactions is essential for triggering ultralong RTP from the doping PVA system, among which the doping film TPA-2Py@PVA exhibits excellent RTP property with an ultralong lifetime of 798.4 ms and a high quantum yield of 15.2%. By further co-doping with the commercially available fluorescent dye, multicolor afterglow is obtained via phosphorescence energy transfer. Meanwhile, the doped PMMA system exhibits reversible photoactivated ultralong RTP properties under continuous UV irradiation. Finally, potential applications of these doped PVA and PMMA systems with ultralong lifetime, multicolor afterglow, and photoactivated ultralong RTP in multidimensional anti-counterfeiting are demonstrated.


Asunto(s)
Polimetil Metacrilato , Rayos Ultravioleta , Temperatura , Aminas , Piridinas , Polímeros
3.
Artículo en Inglés | MEDLINE | ID: mdl-31847259

RESUMEN

At present particulate matter (PM2.5) pollution represents a serious threat to the public health and the national economic system in China. This paper optimizes the whitening coefficient in a grey Markov model by a genetic algorithm, predicts the concentration of fine particulate matter (PM2.5), and then quantifies the health effects of PM2.5 pollution by utilizing the predicted concentration, computable general equilibrium (CGE), and a carefully designed exposure-response model. Further, the authors establish a social accounting matrix (SAM), calibrate the parameter values in the CGE model, and construct a recursive dynamic CGE model under closed economy conditions to assess the long-term economic losses incurred by PM2.5 pollution. Subsequently, an empirical analysis was conducted for the Beijing area: Despite the reduced concentration trend, PM2.5 pollution continued to cause serious damage to human health and the economic system from 2013 to 2020, as illustrated by various facts, including: (1) the estimated premature deaths and individuals suffering haze pollution-related diseases are 156,588 (95% confidence intervals (CI): 43,335-248,914)) and six million, respectively; and (2) the accumulated labor loss and the medical expenditure negatively impact the regional gross domestic product, with an estimated loss of 3062.63 (95% CI: 1,168.77-4671.13) million RMB. These findings can provide useful information for governmental agencies to formulate relevant environmental policies and for communities to promote prevention and rescue strategies.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire/economía , Material Particulado/análisis , Salud Pública/economía , Contaminación del Aire/efectos adversos , Algoritmos , China , Análisis Costo-Beneficio , Humanos , Cadenas de Markov , Modelos Económicos
4.
Artículo en Inglés | MEDLINE | ID: mdl-31266268

RESUMEN

Econometrics and input-output models have been presented to construct a joint model (i.e., an EC + IO model) in the paper, which is characterized by incorporating the uncertainty of the real economy with the detailed departmental classification structure, as well as adding recovery period variables in the joint model to make the model dynamic. By designing and implementing a static model, it is estimated that the indirect economic loss for the transportation sector caused by representative haze pollution of Beijing in 2013 was 23.7 million yuan. The industrial-related indirect losses due to the direct economic losses incurred by haze pollution reached 102 million yuan. With the constructed dynamic model, the cumulative economic losses for the industrial sectors have been calculated for the recovery periods of different durations. The results show that: (1) the longer the period that an industrial department returns to normal output after haze pollution has impacted, the greater the cumulative economic loss will be; (2) when the recovery period is one year, the cumulative economic loss value computed by the dynamic EC + IO model is much smaller than the loss value obtained by the static EC + IO model; (3) the recovery curves of industrial sectors show that the recovery rate at the early stage is fast, while it is slow afterwards. Therefore, the governance work after the occurrence of haze pollution should be launched as soon as possible. This study provides a theoretical basis for evaluating the indirect economic losses of haze pollution and demonstrates the value of popularization and application.


Asunto(s)
Contaminación del Aire/economía , Modelos Econométricos , Beijing , Industrias , Transportes
5.
Artículo en Inglés | MEDLINE | ID: mdl-30935121

RESUMEN

In this paper, a vector autoregression (VAR) model has been constructed in order to analyze a two-way mechanism between PM2.5 pollution and industry development in Beijing via the combination of an impulse response function and variance decomposition. According to the results, long-term equilibrium interconnection was found between PM2.5 pollution and the development of primary, secondary, and tertiary industries. One-way Granger causalities were found in the three types of industries shown to contribute to PM2.5 pollution, though the three industries showed different scales of influences on the PM2.5 pollution that varied for about 1⁻2 years. The development of the primary and secondary industries increased the emission of PM2.5, but the tertiary industry had an inhibitory effect. In addition, PM2.5 pollution had a certain inhibitory effect on the development of the primary and secondary industries, but the inhibition of the tertiary industry was not significant. Therefore, the development of the tertiary industry can contribute the most to the reduction of PM2.5 pollution. Based on these findings, policy-making recommendations can be proposed regarding upcoming pollution prevention strategies.


Asunto(s)
Industrias/organización & administración , Material Particulado/análisis , Beijing , Contaminación Ambiental , Humanos , Modelos Organizacionales
6.
Zhong Yao Cai ; 34(8): 1255-9, 2011 Aug.
Artículo en Chino | MEDLINE | ID: mdl-22233043

RESUMEN

OBJECTIVE: To explore the feasibility of total phenolics from Abnormal Savda Munziq on treating human cervical carcinoma. METHODS: MTT assay was used to determine the growth inhibition ratio and IC50 on Hela cells and SiHa cells after treated with different concentrations of total phenolics. Morphologic changes of cells were observed by inverted microscope. RESULTS: Total phenolics inhibited the proliferation of Hela cells in the concentration range of 25 - 125 microg/mL; Total phenolics inhibited the proliferation of SiHa cells in the concentration range of 75 - 175 microg/mL; The inhibitory actions of total phenolics on the Hela and SiHa appeard dose-effect relationship and time-effect relationship obviously (P < 0.01); The IC50 of Hela was (125.26 +/- 16.15) microg/mL after 48h total phenolics treatment; The IC50 of SiHa was (134.51 +/- 2.55) microg/mL after 48h total phenolics treatment. And there was no statistical sense in the disparation of them (P > 0.05); Both of the cells showed apoptosis character evidently after total phenolics treatment, Along with the increasing of the concentration and the action time, morphologic changes of cells were more obviously. CONCLUSION: Total phenolics could inhibit the growth of Hela cells and SiHa cells and the inhibitory actions of total phenolics on the two cells is almostly the same. Therefore, total phenolics from abnormal savda munziq is deserved to be further studied for treating human cervical carcinoma.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Proliferación Celular/efectos de los fármacos , Fenoles/farmacología , Plantas Medicinales/química , Neoplasias del Cuello Uterino/patología , Antineoplásicos Fitogénicos/administración & dosificación , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Femenino , Células HeLa , Humanos , Fenoles/administración & dosificación , Factores de Tiempo , Neoplasias del Cuello Uterino/metabolismo
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