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1.
Appl Opt ; 63(8): 2020-2029, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38568643

RESUMO

Due to the inherent tendency to be blocked by obstacles, reliability is a major challenge for visible light communication (VLC). The intelligent reflective surface (IRS) is an effective way to reduce or eliminate the influence of blockage in the VLC system. However, the complexity increases correspondingly due to complex shadow analysis when access points (APs), IRSs, and obstacles coexist. We proposed a robust layout optimization scheme for the IRS-VLC system to resist blockages. First, we model the random obstructions based on spatial geometry methods. Second, we build the optimization problem model considering consistent illumination, achievable data rate (ADR), the positions of the APs, and the directions of the IRS array. In order to achieve this objective, we develop an anti-occlusion method based on the non-dominated sorting genetic algorithm-II (NSGA-II) to get the Pareto front and use enhanced measurement functions (ASFs) to extract the best solution. Simulation results show that the proposed scheme works well in the IRS-VLC system. It is noteworthy that the rectangle layout has always demonstrated superior performance in the IRS-VLC system compared to other traditional layouts.

2.
Adv Mater ; : e2402480, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38657757

RESUMO

The perovskite/Cu(InGa)Se2 (CIGS) tandem solar cells (TSCs) presents a compelling technological combination poised for the next generation of flexible and lightweight photovoltaic (PV) tandem devices, featuring a tunable bandgap, high power conversion efficiency (PCE), lightweight flexibility, and enhanced stability and durability. Over the years, the imperative to enhance the performance of wide bandgap (WBG) perovskite solar cells (PSCs) has grown significantly, particularly in the context of a flexible tandem device. In this study, an all-round passivation strategy known as Dual Passivation at Grains and Interfaces (DPGI) is introduced for WBG PSCs in perovskite/CIGS tandem structures. The implementation of DPGI is tailored to improve film crystallinity and passivate defects across the solar cell structure, leading to a substantial performance enhancement for WBG PSCs. Subsequently, both rigid and flexible tandem devices are assembled. Impressively, a fully flexible 4T perovskite/CIGS TSCs is successfully fabricated with a PCE of 26.57%, making it the highest value in this field and highlighting its potential applications in the next generation of flexible lightweight PV tandem devices.

3.
Opt Express ; 30(22): 40455-40469, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36298978

RESUMO

In this paper, an integrated visible light communication and positioning (VLCP) code division multiple access (CDMA) system is proposed for recovering original user data and obtaining positioning information simultaneously. A generalized modification method for balanced bipolar code set is presented, which can be applied to VLCP-CDMA system with intensity modulation. Both modified bipolar code sets, zero correlation zone (ZCZ) code set and Walsh code set, are employed and evaluated in VLCP-CDMA systems. When considering synchronous and quasi-synchronous (QS) systems, it is demonstrated that the modified ZCZ code set with ideal zero correlation zone properties performs better communication and positioning performance than the modified Walsh code set by system simulations and experiments. As a result, a bit error rate (BER) of 1.8×10-3 and an average positioning error of 1.50 cm are successfully obtained by adopting modified ZCZ code set in a 4-user real-time VLCP-CDMA system. It will offer a promising solution to meet both communication and positioning requirements of future intelligent systems.

4.
Polymers (Basel) ; 15(1)2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36616454

RESUMO

In order to investigate the high and low temperature rheological properties and fuel corrosion resistance of epoxy resin on SBS modified asphalt, epoxy resin/SBS composite modified asphalt (ER/SBS) was prepared by high-speed shear. Moreover, composite modified bitumen with different proportions were designed based on the uniform design method and the basic performance index test was performed. The optimal composite mixing ratio of the ER and SBS modifier in composite modified asphalt (2.3% and 3.8%, respectively) was determined. Temperature scanning and a multiple stress creep test (MSCR) on ER/SBS composite modified asphalt with different ER content before and after oil corrosion was carried out using a dynamic shear rheometer (DSR). In addition, the high temperature rheological properties of different ER contents and composite modified asphalt after oil corrosion were evaluated by combing DSR measurements with the test data. The creep stiffness (S) and creep rate (m) indexes were obtained by a bending rheometer (BBR), and the effect of ER on the low-temperature rheological properties of SBS modified bitumen was investigated. The influence of the modifier incorporation on the micromorphology of asphalt and the change of micromorphology of asphalt after oil corrosion were analyzed by fluorescence microscopy. The test results show that the incorporation of 2.3% ER and 3.8% SBS can effectively improve the high temperature performance of SBS modified asphalt under the premise of cost saving. Moreover, the composite modified asphalt doped with ER can effectively improve the resistance of SBS modified asphalt to fuel corrosion at high temperatures, and the greatest improvement in the oil corrosion resistance of composite modified asphalt is observed at the ER content of 2.3%.

5.
Biochem Biophys Res Commun ; 516(4): 1167-1174, 2019 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-31284954

RESUMO

Promotion of wound healing is one of the most important fields in clinical medical research. This study aimed to evaluate the potential use of a new surface-structured bacterial cellulose(S-BC) biomaterial with human urine-derived stem cells (hUSCs) for wound healing. In vitro, EA.hy926 were inoculated on structured/non-structured bacterial cellulose, and the growth of EA.hy926 on bacterial cellulose in medium with/without conditioned medium of the hUSCs were observed to explore the effect of bacterial cellulose's surface structure and hUSCs-CM on vascular endothelial cell growth. In vivo, we covered wound surface with various BC materials and/or injected the hUSCs into the wound site on group BC, group S-BC, group hUSCs, group BC + hUSCs, group S-BC + hUSCs to evaluate the effect of S-BC and hUSCs on wound healing in rat full-thickness skin defect model. In vitro study, surface structure of S-BC could promote the growth and survival of EA.hy926, and the hUSCs-CM could further promote the proliferation of EA.hy926 on S-BC. In vivo study, wound healing rate of the group BC, group S-BC, group hUSCs was significantly accelerated, accompanied by faster re-epithelialization, collagen production and neovascularization than control group. It is note worthy that the effect of S-BC on wound healing was better than BC, the effect of S-BC + hUSCs on wound healing was better than BC + hUSCs. Moreover, the effect of S-BC combined with hUSCs on wound is better than treated with S-BC or hUSCs alone. All the findings suggest that the combination of S-BC and hUSCs could facilitate skin wound healing by promoting angiogenesis. This combination of the role of stem cells and biomaterial surface structures may provide a new way to address clinical wound healing problems.


Assuntos
Materiais Biocompatíveis/uso terapêutico , Celulose/uso terapêutico , Neovascularização Fisiológica , Transplante de Células-Tronco , Cicatrização , Animais , Materiais Biocompatíveis/química , Linhagem Celular , Células Cultivadas , Celulose/química , Células Endoteliais/citologia , Humanos , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/uso terapêutico , Ratos , Transplante de Células-Tronco/métodos , Células-Tronco/citologia , Propriedades de Superfície , Alicerces Teciduais/química
6.
Eur J Obstet Gynecol Reprod Biol ; 210: 370-375, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28157643

RESUMO

OBJECTIVES: Ectopic pregnancies are among the leading causes of maternal morbidity and mortality in both developed and emerging nations, but tests for early, accurate, and convenient detection are lacking. STUDY DESIGN: Between January 2013 and February 2015, 504 women with tubal pregnancy were prospectively recruited, and their clinical characteristics were recorded. Samples of peritoneal fluid were collected by culdocentesis, and venous blood was drawn from the antecubital vein. In samples from each source, levels of the following biochemical markers were measured: cancer antigen 125 (CA125), human chorionic gonadotropin (hCG), progesterone, vascular endothelial growth factor, and creatine kinase. RESULTS: The ratios of biochemical markers in the peritoneal fluid and in the blood (Rp/v) were calculated. The median of Rp/v-CA125 and Rp/v-hCG were significantly lower in the ruptured ectopic pregnancy group than in the unruptured group. The optimal cutoff value to detect ectopic pregnancy rupture was 401.5U/mL as the upper limit for peritoneal CA125, with a sensitivity of 93.5% and specificity of 74.2%. The optimal cutoff value was 18.7 as the upper limit in the peritoneal fluid/blood ratio (Rp/v) of CA125, with a sensitivity of 77.5% and specificity of 68.4%. CONCLUSIONS: In countries with poor access to laparoscopy, culdocentesis is useful. In this study, culdocentesis provided additional information for management of abdominal pain when laparoscopy is not available. The authors propose Rp/v cutoff values that can be used conveniently and quickly to diagnose ruptured ectopic pregnancies and bleeding, enabling rapid and appropriate therapeutic responses.


Assuntos
Líquido Ascítico/química , Biomarcadores/sangue , Gravidez Tubária/sangue , Adulto , Antígeno Ca-125/sangue , Gonadotropina Coriônica/sangue , Creatina Quinase/sangue , Feminino , Humanos , Proteínas de Membrana/sangue , Paracentese , Gravidez , Gravidez Tubária/diagnóstico , Progesterona/sangue , Estudos Prospectivos , Ruptura Espontânea/sangue , Fator A de Crescimento do Endotélio Vascular/sangue , Adulto Jovem
7.
Cell Death Dis ; 7(10): e2402, 2016 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-27711077

RESUMO

Dysfunction of nuclear factor-κB (NF-κB) signaling has been causally associated with numerous human malignancies. Although the NF-κB family of genes has been implicated in endometrial carcinogenesis, information regarding the involvement of central regulators of NF-κB signaling in human endometrial cancer (EC) is limited. Here, we investigated the specific roles of canonical and noncanonical NF-κB signaling in endometrial tumorigenesis. We found that NF-κB RelB protein, but not RelA, displayed high expression in EC samples and cell lines, with predominant elevation in endometrioid adenocarcinoma (EEC). Moreover, tumor cell-intrinsic RelB was responsible for the abundant levels of c-Myc, cyclin D1, Bcl-2 and Bcl-xL, which are key regulators of cell cycle transition, apoptosis and proliferation in EEC. In contrast, p27 expression was enhanced by RelB depletion. Thus, increased RelB in human EC is associated with enhanced EEC cell growth, leading to endometrial cell tumorigenicity. Our results reveal that regulatory RelB in noncanonical NF-κB signaling may serve as a therapeutic target to block EC initiation.


Assuntos
Carcinogênese/metabolismo , Carcinogênese/patologia , Carcinoma Endometrioide/metabolismo , Carcinoma Endometrioide/patologia , Ciclo Celular , NF-kappa B/metabolismo , Fator de Transcrição RelA/metabolismo , Fator de Transcrição RelB/metabolismo , Animais , Apoptose/genética , Pontos de Checagem do Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Fase G1/genética , Humanos , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Fenótipo , Fase S/genética , Transdução de Sinais/genética
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