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1.
PLoS One ; 18(4): e0281271, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37058517

RESUMO

As an important engine for high-quality economic development, the digital economy is gradually integrating with the rural logistics industry. This trend is contributing to making rural logistics a fundamental, strategic, and pioneering industry. However, some valuable topics remain unstudied, such as whether they are coupled and whether there is variability in the coupling system across the provinces. Therefore, this article takes system theory and coupling theory as the analytical framework, aiming to better elaborate the subject's logical relationship and operational structure of the coupled system, which is composed of a digital economy subsystem and a rural logistics subsystem. Furthermore, 21 provinces are seen as the research object in China, and the coupling coordination model is constructed, aiming to verify the coupling and coordination relationship between the two subsystems. The results suggest that two subsystems are coupled and coordinated in the same direction, and they feed back and influence each other. During the same period, four echelons are divided and there is variability in the coupling and coordination between the digital economy and rural logistics, according to the coupling degree (CD) and coupling coordination degree (CCD). Findings presented can serve as a useful reference for the evolutionary laws of the coupled system. The findings presented here can serve as a useful reference for the evolutionary laws of coupled systems. Moreover, it further provides ideas for the development between rural logistics and the digital economy.


Assuntos
Conservação dos Recursos Naturais , Desenvolvimento Econômico , China , Indústrias , Cidades
2.
Sci Prog ; 106(1): 368504231160410, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36974461

RESUMO

This article deals with a dynamic decision-making model for a low-carbon supply chain which consists of a manufacturer and a platform retailer. Consideration of delay effects, a delayed differential equation for the effect of low-carbon investment efforts (LIE) in R&D and low-carbon promotional effort (LPE) on low-carbon goodwill (LG) is developed. Moreover, Hamilton's function is applied to solve the decision problem of optimal control. In the model, the differences between the agency selling and reselling patterns are analyzed by comparing LIE, LPE, LG, and net discounted profit. The commission system is a key measure for dynamic decision making on low-carbon products, while the commission rate is also an important reference point for decision making on cooperation patterns. In contrast to the findings of previous studies, this article derives specific thresholds for commissions. Furthermore, this study considers delay effects from a dynamic perspective. The findings show differences in both decentralized and centralized decision-making solutions for supply chains as the delay time changes. The proposed models are analyzed mathematically and numerical examples are illustrated to justify the feasibility of the model in reality. This study provides new insights into the choice of platform sales patterns for firms to develop agency selling and reselling partnership solutions in practice.

3.
ACS Appl Mater Interfaces ; 14(39): 45032-45041, 2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36153948

RESUMO

Triple-negative breast cancer (TNBC) is an aggressive BC subtype with a higher metastatic rate and a worse 5-year survival ratio than the other BC. It is an urgent need to develop a noninvasive treatment with high efficiency to resist TNBC cell proliferation and invasion. Internal wireless electric stimulation (ES) based on piezoelectric materials is an emerging noninvasive strategy, with adjustable ES intensity and excellent biosafety. In this study, three different barium titanate nanoparticles (BTNPs) with different crystal phases and piezoelectric properties were studied. Varying intensities of internal ES were generated from the three BTNPs (i.e., BTO, U-BTO, P-BTO). In vitro tests revealed that the internal ES from BTNPs was efficient at reducing the proliferative potential of cancer cells, particularly BC cells. In vitro experiments on MDA-MB-231, a typical TNBC cell line, further revealed that the internal wireless ES from BTNPs significantly inhibited cell growth and migration up to about 82% and 60%, respectively. In vivo evaluation of MDA-MB-231 tumor-bearing mice indicated that internal ES not only resisted almost 70% tumor growth but also significantly inhibited lung metastasis. More importantly, in vitro and in vivo studies demonstrated a favorable correlation between the anticancer impact and the intensities of ES. The underlying mechanism of MDA-MB-231 cell proliferation and metastasis inhibition caused by internal ES was also investigated. In summary, our results revealed the effect and mechanism of internal ES from piezoelectric nanoparticles on TNBC cell proliferation and migration regulation and proposed a promising noninvasive therapeutic strategy for TNBC with minimal side effects while exhibiting good therapeutic efficiency.


Assuntos
Nanopartículas , Neoplasias de Mama Triplo Negativas , Animais , Bário/farmacologia , Bário/uso terapêutico , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Estimulação Elétrica , Humanos , Camundongos , Nanopartículas/química , Neoplasias de Mama Triplo Negativas/tratamento farmacológico
4.
ACS Biomater Sci Eng ; 8(6): 2419-2427, 2022 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-35642535

RESUMO

Postsurgical infection of orthopedic fixation materials is considered to be the main cause of fixation failure. To address the problem, clinical treatment often relies on long-term antibiotics, secondary surgery, and so forth, which cause pain and suffering to patients. Constructing a light-responsive surface structure on the implant has attracted widespread attention for the management of postsurgical infections because of its noninvasiveness and controllability. Nevertheless, the application of light-responsive structures on implants is still limited by their unsafety and instability. In this work, a black titanium oxide layer with a multilevel structure and lattice defects was in situ constructed on a titanium alloy through pulsed laser ablation treatment. Under the synergistic effect of the multilevel structure and crystal defects, the surface of the titanium alloy exhibited good near-infrared light-responsive photothermal ability. The black titanium oxide multilevel structure reached high antibacterial efficiencies of about 99.37 and 99.29% against Staphylococcus aureus and Escherichia coli under 10 min near-infrared light irradiation. Furthermore, the black titanium oxide layer possessed similar biocompatibility compared with the titanium alloy. This near-infrared light-responsive photothermal therapy based on the construction of a multilevel structure and introduction of lattice defects provides an effective strategy for clinical postsurgical infections of orthopedic fixation.


Assuntos
Ligas , Titânio , Antibacterianos/química , Antibacterianos/farmacologia , Escherichia coli , Humanos , Terapia Fototérmica , Titânio/química , Titânio/farmacologia
5.
Bioact Mater ; 18: 399-408, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35415302

RESUMO

Pathological angiogenesis frequently occurs in tumor tissue, limiting the efficiency of chemotherapeutic drug delivery and accelerating tumor progression. However, traditional vascular normalization strategies are not fully effective and limited by the development of resistance. Herein, inspired by the intervention of endogenous bioelectricity in vessel formation, we propose a wireless electrical stimulation therapeutic strategy, capable of breaking bioelectric homeostasis within cells, to achieve tumor vascular normalization. Polarized barium titanate nanoparticles with high mechano-electrical conversion performance were developed, which could generate pulsed open-circuit voltage under low-intensity pulsed ultrasound. We demonstrated that wireless electrical stimulation significantly inhibited endothelial cell migration and differentiation in vitro. Interestingly, we found that the angiogenesis-related eNOS/NO pathway was inhibited, which could be attributed to the destruction of the intracellular calcium ion gradient by wireless electrical stimulation. In vivo tumor-bearing mouse model indicated that wireless electrical stimulation normalized tumor vasculature by optimizing vascular structure, enhancing blood perfusion, reducing vascular leakage, and restoring local oxygenation. Ultimately, the anti-tumor efficacy of combination treatment was 1.8 times that of the single chemotherapeutic drug doxorubicin group. This work provides a wireless electrical stimulation strategy based on the mechano-electrical conversion performance of piezoelectric nanoparticles, which is expected to achieve safe and effective clinical adjuvant treatment of malignant tumors.

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