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1.
Heliyon ; 10(11): e32213, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38882358

RESUMEN

Drought stress has a significant impact on the quality and quantity of lake water. Understanding this impact is crucial for preventing water security risks and pollution recovery. However, there is a lack of systemic understanding of how drought affects water quality and quantity, and how they change in multiple dimensions. This manuscript established a synthesized methodology with the principles to judge the applicability and three steps of application to detect the change in water quality and water level under severe drought in Xingyun Lake, China. Results show that (1) The water level and water quality of Xingyun Lake have a synchronous and evident response to drought during 2009-2014. The rainfall during 2008-2015 declined by 22.9 % to normal, and the inundated area and lake water depth in 2012 decreased by 10.50 % from 2002 to 1.38 m to the average depth, respectively. The pollution index climbed above 1.21 after 2008, fluctuating around 1.42. (2) Under drought, the water quality indicators significantly changed in the terms of the overall feature, trend, eigenvalue, and morphological characteristics. The water quality indicators of Set2008-2015 are significantly different from set2000-2007 and not in the groups of set1994-2000. The morphological characteristics of water quality indicators in set2008-2015 differs significantly from that in set2000-2007 shown by the minimum, maximum, median, quartiles, and extreme values. (3) Although NH3-N showed no significant change, the water quality deteriorated in the physical, chemical, and biological aspects. The TP, IMN, and BOD5 changed more evidently than DO and NH3-N. (4) Water quality grade and indicator concentration deteriorated significantly and sharply under severe drought and are threatened deeply by TP and TN. The synthesized methodology is scientifically constructed and canbe employed in the characteristics cognition of water quality and water level to severe drought in and out of this research. And the intervention time and various regulating measures for pollution degradation and water quality recovery canbe constructed based on the multi-dimensional analysis of water quality change under drought evolution.

2.
PLoS One ; 18(6): e0284238, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37267409

RESUMEN

This study investigated the impact of axial load on the dynamic response of reinforced concrete (RC) members to asymmetrical lateral impact loads. A series of asymmetrical-span impact tests were conducted on circular and square RC members with and without Carbon Fiber Reinforced Polymers (CFRP) while varying the axial compression ratios. The impact process was simulated using ABAQUS software, and the time history curves of deflection and impact were measured. The study found that specific impact loads caused bending and shearing failures. The axial compression ratio ranged from 0.05 to 0.13 when the impact curve reached its maximum deflection before the component's impact resistance decreased. Analysis of the impact point and inclined crack location revealed that axial load affects the maximum local concrete. The speed of inclined crack penetration and inclined cracks take longer to form, with weaker resistance to damage to local concrete when the axial compression ratio is between 0.05 and 0.13. When the axial compression ratio is greater than 0.13, inclined cracks form sooner with more brittle and severe damage to the impact point's concrete. The study also identified key parameters affecting the dynamic response of RC members, including impact height, CFRP layer thickness, axial force, and impact location. Thicker CFRP layers in RC can improve impact resistance, especially when the impact location is farther from the center. However, there is a limit to the impact of axial force on this resistance.


Asunto(s)
Compresión de Datos , Polímeros , Fibra de Carbono , Plásticos
3.
Sci Rep ; 12(1): 14793, 2022 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-36042277

RESUMEN

Traffic accidents and derailed train-related incidents have occurred more often than ever in recent years, resulting in some economic damage and casualties. Reinforced concrete (RC) constructions often involve derailed train and vehicle accidents. Rarely are such side collisions studied in previous studies. To do this, high-fidelity simulation-based finite-element (FE) models are created in this paper to accurately simulate the collision of circular RC members with a derailed train. The reinforced concrete member structure is common in high-speed railway stations. The impact energy of the impact body is significant, causing structural member failure. It analyses the dynamic behavior of reinforced concrete members under unequal span impact loads. Numerical implementations of impact issues are discussed from the perspective of geometric, contact, and material properties. The reliability and precision of the ABAQUS code to solve impact issues are verified by comparing failure modes, impact, and deflection time history experimental outputs. By analysing the impact response characteristics, used the control variables to study the failure process and mode (including the characteristics of impact and reaction forces, deflection time history curve, impact force-deflection curve, and bearing reaction force-deflection curve). The reinforcement ratio, impact velocity, concrete strength, and slenderness ratio significantly affect shear crack pattern and development. Changes in impact velocity and slenderness ratio also affect member failure modes.

4.
IEEE Trans Image Process ; 30: 5678-5691, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34125680

RESUMEN

RGB-thermal salient object detection (SOD) aims to segment the common prominent regions of visible image and corresponding thermal infrared image that we call it RGBT SOD. Existing methods don't fully explore and exploit the potentials of complementarity of different modalities and multi-type cues of image contents, which play a vital role in achieving accurate results. In this paper, we propose a multi-interactive dual-decoder to mine and model the multi-type interactions for accurate RGBT SOD. In specific, we first encode two modalities into multi-level multi-modal feature representations. Then, we design a novel dual-decoder to conduct the interactions of multi-level features, two modalities and global contexts. With these interactions, our method works well in diversely challenging scenarios even in the presence of invalid modality. Finally, we carry out extensive experiments on public RGBT and RGBD SOD datasets, and the results show that the proposed method achieves the outstanding performance against state-of-the-art algorithms. The source code has been released at: https://github.com/lz118/Multi-interactive-Dual-decoder.

5.
Mol Gen Genet ; 183(3): 514-7, 1981.
Artículo en Inglés | MEDLINE | ID: mdl-6460912

RESUMEN

The genes for the beta and beta' subunits of RNA polymerase, rpoB and rpoC, and the genes for the two ribosomal proteins, rplL and rplJ, are part of the beta operon. Although this operon and contains a single strong promoter, the genes of the operon are not always coordinately expressed in vivo. This has now been confirmed in vitro where the lack of coordinate expression has been shown to be correlated with the selective inhibition of rpoB and rpoC gene expression by RNa polymerase. Rifampicin, which stops the initiation of transcription, also relieves this autogenous inhibition of beta and beta' (beta beta') synthesis. The inhibitory action of RNA polymerase and its reversal by rifampicin most likely occurs at a posttranscriptional or translation level.


Asunto(s)
ARN Polimerasas Dirigidas por ADN/genética , ARN Polimerasas Dirigidas por ADN/farmacología , Precursores Enzimáticos/genética , Genes/efectos de los fármacos , Transcripción Genética/efectos de los fármacos , Bacteriófago lambda/genética , Sistema Libre de Células , Escherichia coli/genética , Regulación de la Expresión Génica
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