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1.
Food Chem ; 460(Pt 2): 140422, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39068794

RESUMEN

Effects of sodium alginate (SA) on the non-covalent interaction between soybean protein isolate (SPI) and quercetin (Que) were investigated by multispectral technology, molecular docking and dynamics simulation technology. Structural alterations of the binary complexes were observed after SA addition, characterized by a red shift of maximum fluorescence emission wavelength. The introduction of 0.1% (w/v) SA led to a reduction of 12.3% in the α-helix and ß-sheet structures, accompanied by 12.6% increase in the ß-turn and random coil conformations. The binding of SA to SPI provided electrostatic interactions and facilitated the subsequent binding of SPI to Que. Molecular docking confirmed that hydrophobic interactions and electrostatic interactions were also the main driving force. Molecular dynamics simulation emphasized that the ternary complexes with SA exhibited greater stability compared to the binary ones. The foaming and emulsifying properties of SPI-Que complexes were enhanced by 33.76% and 68.28%, respectively, due to the addition of SA.

2.
Proc Inst Mech Eng H ; : 9544119241261891, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39045922

RESUMEN

The pancreas is adjacent to critical organs; excessive microwave ablation (MWA) can result in serious complications. The purpose of this paper is to provide the reference data of pancreas MWA for clinicians, analyze the ablation outcomes under different ablation parameters, and determine the critical temperature of pancreatic surface fat liquefaction outflow. Combinations of two power levels (30 W and 55 W), three antenna diameters (1.3 mm, 1.6 mm, and 1.9 mm), and three ablation times (1 min, 1.5 min, and 2 min) were applied to an ex vivo pig pancreas. Temperature measurements were taken at four thermocouple points. The center point is located 5 mm horizontally from the antenna slot, with a temperature measurement point located 5 mm above, below, and to the right of the center point. Main effect analysis and variance analysis were used to quantify the influences of each factor on the ablation outcomes. At 30 W, the antenna diameter contributing the most at 48.5%. At 30 W-1.3 mm-1 min, the spherical index (1.41) is closest to 1. At 55 W, the coagulation zone size was almost only affected by the ablation time, with a contribution rate of 28.7%, the temperature at point C exceeds point B. On the surface of the ex vivo porcine pancreas, the fat outflow temperature was 54ã. Ablation combinations with low power, short duration, and small antenna diameter results in a more nearly spherical coagulation zone. When performing MWA on the pancreas, it is advisable to avoid areas with higher fat content, while keeping the pancreatic surface temperature below 54°C.

3.
Sci Bull (Beijing) ; 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39084926

RESUMEN

Two-dimensional noble transition metal chalcogenide (NTMC) semiconductors represent compelling building blocks for fabricating flexible electronic and optoelectronic devices. While binary and ternary compounds have been reported, the existence of quaternary NTMCs with a greater elemental degree of freedom remains largely unexplored. This study presents the pioneering experimental realization of a novel semiconducting quaternary NTMC material, AuPdNaS2, synthesized directly on Au foils through chemical vapor deposition. The ribbon-shaped morphology of the AuPdNaS2 crystal can be finely tuned to a thickness as low as 9.2 nm. Scanning transmission electron microscopy reveals the atomic arrangement, showcasing robust anisotropic features; thus, AuPdNaS2 exhibits distinct anisotropic phonon vibrations and electrical properties. The field-effect transistor constructed from AuPdNaS2 crystal demonstrates a pronounced anisotropic conductance (σmax/σmin = 3.20) under gate voltage control. This investigation significantly expands the repertoire of NTMC materials and underscores the potential applications of AuPdNaS2 in nano-electronic devices.

4.
Adv Mater ; : e2405858, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38899584

RESUMEN

To improve thermoelectric efficiency, various tactics have been employed with considerable success to decouple intertwined material attributes. However, the integration of magnetism, derived from the unique spin characteristic that other methods cannot replicate, has been comparatively underexplored and presents an ongoing intellectual challenge. A previous research has shown that vacancy-filling Heuslers offer a highly adaptable framework for modulating thermoelectric properties. Here, it is demonstrated how intrinsic magnetic-electrical-thermal coupling can enhance the thermoelectric performance of vacancy-filling Heusler alloys. The materials, Nb0.75Ti0.25FeCrxSb with 0 ≤ x ≤ 0.1, feature a fraction of magnetic Cr ions that randomly occupy the vacancy sites of the Nb0.75Ti0.25FeSb half-Heusler matrix. These alloys achieve a remarkable thermoelectric figure of merit (zT) of 1.21 at 973 K, owing to increased Seebeck coefficient and decreased thermal conductivity. The mechanism is primarily due to the introduction of magnetism, which increases the density-of-states effective mass (reaching levels up to 15 times that of a free electron's mass) and simultaneously reduces the electronic thermal conductivity. Mass and strain-field fluctuations further reduce the lattice thermal conductivity. Even higher zT values can potentially be achieved by carefully balancing electron mobility and effective mass. This work underscores the substantial prospects for exploiting magnetic-electrical-thermal synergies in cutting-edge thermoelectric materials.

5.
Braz J Med Biol Res ; 57: e13528, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38896645

RESUMEN

Unilateral vocal cord paralysis is frequently observed in patients who undergo thyroid surgery. This study explored the correlation between acoustic voice analysis (objective measure) and Voice Handicap Index (VHI, a self-assessment tool). One hundred and forty patients who had thyroid surgery with or without postoperative unilateral vocal cord paralysis (PVCP and NPVCP) were included. The patients were evaluated by the VHI and Dysphonia Severity Index (DSI) tools. VHI scores were significantly higher in PVCP patients than in NPVCP patients. Jitter (%) and shimmer (%) were significantly increased, whereas DSI was significantly decreased in PVCP patients. Receiver operating characteristics curve revealed that VHI scores were associated with the diagnosis of PVCP, of which VHI total score yielded an area under the curve (AUC) of 0.81. Among acoustic parameters, DSI was highly associated to PVCP (AUC=0.82, 95%CI=0.75 to 0.89). Moreover, we found a correlation between VHI scores and voice acoustic parameters. Among them, DSI had a moderate correlation with functional and VHI scores, as suggested by an R value of 0.41 and 0.49, respectively. VHI scores and acoustic parameters were associated with the diagnosis of PVCP.


Asunto(s)
Índice de Severidad de la Enfermedad , Tiroidectomía , Parálisis de los Pliegues Vocales , Calidad de la Voz , Humanos , Parálisis de los Pliegues Vocales/etiología , Parálisis de los Pliegues Vocales/fisiopatología , Parálisis de los Pliegues Vocales/diagnóstico , Masculino , Femenino , Persona de Mediana Edad , Adulto , Tiroidectomía/efectos adversos , Complicaciones Posoperatorias/diagnóstico , Acústica del Lenguaje , Anciano , Curva ROC , Evaluación de la Discapacidad , Disfonía/etiología , Disfonía/diagnóstico , Disfonía/fisiopatología
6.
Phytomedicine ; 130: 155745, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-38833788

RESUMEN

BACKGROUND AND AIMS: Isogarcinol, a natural compound extracted from the fruits of Garcinia oblongifolia, has potential chemopreventive activity. This study aimed to elucidate the anti-tumor effects and mechanism of action of isogarcinol on nasopharyngeal carcinoma (NPC). METHODS: Isogarcinol was isolated from Garcinia oblongifolia by using chromatographic separation. The anti-tumor effects of isogarcinol in NPC cells were tested by MTT assay, flow cytometry, wound healing assay, western blotting, transwell assay, colony formation assay, immunofluorescence, and transmission electron microscopy (TEM). The anti-tumor efficacy in vivo was evaluated in NPC cells xenograft models. RESULTS: Functional studies revealed that isogarcinol inhibited the proliferation, colony formation, migration and invasion abilities of NPC cells in vitro. Isogarcinol caused mitochondrial damage to overproduce reactive oxygen species through reducing the mitochondrial membrane potential and ΔΨm. Isogarcinol also substantially inhibited NPC cells growth in a xenograft tumor model without any obvious toxicity when compared with paclitaxel (PTX). Mechanistic studies have illustrated that isogarcinol increased the Bax/Bcl-2 ratio, cleaved caspase-3, and cytoplasmic cytochrome C levels to induce mitochondrial apoptosis. The ROS overproduction by isogarcinol could suppress EMT pathway via decreasing the levels of p-Akt and Snail. Furthermore, isogarcinol promoted the conversion of LC3-Ⅰ to LC3-Ⅱ, but increased p62 level to block autophagic flux, resulting in the accumulation of damaged mitochondria to promote autophagic cell death in NPC cells. CONCLUSION: This study provides a new theoretical foundation for the anti-tumor application of Garcinia oblongifolia and confirms that isogarcinol could be developed as a candidate drug for NPC treatment with low toxicity.


Asunto(s)
Antineoplásicos Fitogénicos , Garcinia , Ratones Desnudos , Mitocondrias , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Humanos , Garcinia/química , Animales , Mitocondrias/efectos de los fármacos , Línea Celular Tumoral , Carcinoma Nasofaríngeo/tratamiento farmacológico , Neoplasias Nasofaríngeas/tratamiento farmacológico , Antineoplásicos Fitogénicos/farmacología , Especies Reactivas de Oxígeno/metabolismo , Muerte Celular Autofágica/efectos de los fármacos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones Endogámicos BALB C , Ensayos Antitumor por Modelo de Xenoinjerto , Ratones , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Frutas/química
7.
Cancer Lett ; 592: 216927, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38697460

RESUMEN

Glioblastoma (GBM), one of the most malignant brain tumors in the world, has limited treatment options and a dismal survival rate. Effective and safe disease-modifying drugs for glioblastoma are urgently needed. Here, we identified a small molecule, Molephantin (EM-5), effectively penetrated the blood-brain barrier (BBB) and demonstrated notable antitumor effects against GBM with good safety profiles both in vitro and in vivo. Mechanistically, EM-5 not only inhibits the proliferation and invasion of GBM cells but also induces cell apoptosis through the reactive oxygen species (ROS)-mediated PI3K/Akt/mTOR pathway. Furthermore, EM-5 causes mitochondrial dysfunction and blocks mitophagy flux by impeding the fusion of mitophagosomes with lysosomes. It is noteworthy that EM-5 does not interfere with the initiation of autophagosome formation or lysosomal function. Additionally, the mitophagy flux blockage caused by EM-5 was driven by the accumulation of intracellular ROS. In vivo, EM-5 exhibited significant efficacy in suppressing tumor growth in a xenograft model. Collectively, our findings not only identified EM-5 as a promising, effective, and safe lead compound for treating GBM but also uncovered its underlying mechanisms from the perspective of apoptosis and mitophagy.


Asunto(s)
Apoptosis , Neoplasias Encefálicas , Proliferación Celular , Glioblastoma , Mitofagia , Especies Reactivas de Oxígeno , Ensayos Antitumor por Modelo de Xenoinjerto , Glioblastoma/tratamiento farmacológico , Glioblastoma/patología , Glioblastoma/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Humanos , Mitofagia/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/metabolismo , Ratones , Proliferación Celular/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Lisosomas/efectos de los fármacos , Lisosomas/metabolismo , Ratones Desnudos , Serina-Treonina Quinasas TOR/metabolismo , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/metabolismo
8.
J Chem Phys ; 160(13)2024 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-38557836

RESUMEN

VO2 is renowned for its electric transition from an insulating monoclinic (M1) phase, characterized by V-V dimerized structures, to a metallic rutile (R) phase above 340 K. This transition is accompanied by a magnetic change: the M1 phase exhibits a non-magnetic spin-singlet state, while the R phase exhibits a state with local magnetic moments. Simultaneous simulation of the structural, electric, and magnetic properties of this compound is of fundamental importance, but the M1 phase alone has posed a significant challenge to the density functional theory (DFT). In this study, we show none of the commonly used DFT functionals, including those combined with on-site Hubbard U to treat 3d electrons better, can accurately predict the V-V dimer length. The spin-restricted method tends to overestimate the strength of the V-V bonds, resulting in a small V-V bond length. Conversely, the spin-symmetry-breaking method exhibits the opposite trends. Each of these two bond-calculation methods underscores one of the two contentious mechanisms, i.e., Peierls lattice distortion or Mott localization due to electron-electron repulsion, involved in the metal-insulator transition in VO2. To elucidate the challenges encountered in DFT, we also employ an effective Hamiltonian that integrates one-dimensional magnetic sites, thereby revealing the inherent difficulties linked with the DFT computations.

9.
Nat Prod Res ; : 1-8, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38629167

RESUMEN

Tripterygium wilfordii has been historically employed as a conventional botanical insecticide and a plant of medicinal significance. A new dihydroagarofuran sesquiterpene (1) and a new acyclic compound (2), along with seven known compounds (3-9), have been isolated from the aerial parts of Tripterygium wilfordii. The identification of the structures of novel compounds were accomplished through comprehensive spectroscopic analyses, encompassing HRESIMS, NMR, UV, IR, and a comparative analysis with spectroscopic data from compounds previously characterised. In in-vitro bioassay, compound 8 exhibited significant inhibitory activity for NO release in LPS-induced RAW 264.7 cells, with an IC50 value of 15.7 µM.

10.
Trends Genet ; 40(7): 613-620, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38644132

RESUMEN

Camouflage is a classic example of a trait wherein animals respond to natural selection to avoid predation or attract prey. This unique phenomenon has attracted significant recent attention and the rapid development of integrative research methods is facilitating advances in our understanding of the in-depth genetic mechanisms of camouflage. In this review article, we revisit camouflage definitions and strategies and then we examine the underlying mechanisms of the two most common forms of camouflage, crypsis and masquerade, that have recently been elucidated using multiple approaches. We also discuss unresolved questions related to camouflage. Ultimately, we highlight the implications of camouflage for informing various key issues in ecology and evolution.


Asunto(s)
Evolución Biológica , Mimetismo Biológico , Selección Genética , Animales , Mimetismo Biológico/genética , Selección Genética/genética , Conducta Predatoria , Fenotipo , Pigmentación/genética
11.
Pediatr Neonatol ; 2024 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-38538402

RESUMEN

BACKGROUND: This study was to explore the effectiveness of the ABCLOVE exercise on school-aged children with vocal nodules after the treatment of budesonide. METHODS: Eighty-six school-aged children with vocal nodules were divided into control and ABCLOVE therapy groups. Subjective voice assessment and dysphonia severity index (DSI) assessment were performed before and after the 3-month of therapy. RESULTS: A significant improvement was observed in the ABCLOVE therapy group as compared with the control group (p = 0.035). ABCLOVE therapy significantly reduced the hoarseness and roughness scores in school-aged children with vocal nodules. Additionally, a significant reduction in functional score, physical score, emotional score, and total pVHI score was observed in the ABCLOVE therapy group. Moreover, acoustic parameters including jitter (%) and shimmer (%) were significantly reduced, whereas MPT and DSI were increased in school-aged children with vocal nodules who received 3 months of ABCLOVE treatment. CONCLUSION: ABCLOVE therapy displayed effectiveness on school-aged children with vocal nodules after the treatment of budesonide.

12.
Biotechnol J ; 19(3): e2300516, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38472100

RESUMEN

Alternative transcription start sites (TSSs) usage plays a critical role in gene transcription regulation in mammals. However, precisely identifying alternative TSSs remains challenging at the genome-wide level. We report a single-cell genomic technology for alternative TSSs annotation and cell heterogeneity detection. In the method, we utilize Fluidigm C1 system to capture individual cells of interest, SMARTer cDNA synthesis kit to recover full-length cDNAs, then dual priming oligonucleotide system to specifically enrich TSSs for genomic analysis. We apply this method to a genome-wide study of alternative TSSs identification in two different IFN-ß stimulated mouse embryonic fibroblasts (MEFs). The data clearly discriminate two IFN-ß stimulated MEFs. Moreover, our results indicate 81% expressed genes in these two cell types containing multiple TSSs, which is much higher than previous predictions based on Cap-Analysis Gene Expression (CAGE) (58%) or empirical determination (54%) in various cell types. This indicates that alternative TSSs are more pervasive than expected and implies our strategy could position them at an unprecedented sensitivity. It would be helpful for elucidating their biological insights in future.


Asunto(s)
Fibroblastos , Estudio de Asociación del Genoma Completo , Animales , Ratones , Regiones Promotoras Genéticas , Genoma , Genómica , Mamíferos/genética
13.
Antiviral Res ; 223: 105822, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38350497

RESUMEN

Influenza therapeutics with new targets and modes of action are urgently needed due to the frequent emergence of mutants resistant to currently available anti-influenza drugs. Here we report the in vitro and in vivo anti-influenza A virus activities of cyperenoic acid, a natural compound, which was isolated from a Chinese medicine Croton crassifolius Geise. Cyperenoic acid could potently suppress H1N1, H3N2 and H9N2 virus replication with IC50 values ranging from 0.12 to 15.13 µM, and showed a low cytotoxicity against MDCK cells (CC50 = 939.2 ± 60.0 µM), with selectivity index (SI) values ranging from 62 to 7823. Oral or intraperitoneal treatment of cyperenoic acid effectively protected mice against a lethal influenza virus challenge, comparable to the efficacy of Tamiflu. Additionally, cyperenoic acid also significantly reduced lung virus titers and alleviated influenza-induced acute lung injury in infected mice. Mechanism-of-action studies revealed that cyperenoic acid exhibited its anti-influenza activity during the entry stage of viral replication by inhibiting HA-mediated viral fusion. Simulation docking analyses of cyperenoic acid with the HA structures implied that cyperenoic acid binds to the stalk domain of HA in a cavity near the fusion peptide. Collectively, these results demonstrate that cyperenoic acid is a promising lead compound for the anti-influenza drug development and this research provides a useful small-molecule probe for studying the HA-mediated viral entry process.


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A , Subtipo H9N2 del Virus de la Influenza A , Gripe Humana , Sesquiterpenos , Animales , Ratones , Humanos , Subtipo H3N2 del Virus de la Influenza A , Anticuerpos
14.
Ultrason Sonochem ; 103: 106801, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38364485

RESUMEN

Particle engulfment plays a vital role in the application of particulate reinforced metal matrix composites fabricated by ingot metallurgy. During solidification, particles are nevertheless pushed by an advancing front. As a model system, TiB2p/Al composites were used to investigate the particle engulfment facilitated by acoustic cavitation. The implosion of bubbles drives the particles plunging towards the solid/liquid interface, which increases the engulfment probability. The secondary dendrite arms are refined from 271.2 µm to 98.0 µm as a result of the forced movements of TiB2 particles. Owing to the particle engulfment and dendrite refinement, the composite with ultrasound vibration treatment shows a more rapid work-hardening rate and higher strength.

15.
Braz. j. med. biol. res ; 57: e13528, fev.2024. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1564159

RESUMEN

Unilateral vocal cord paralysis is frequently observed in patients who undergo thyroid surgery. This study explored the correlation between acoustic voice analysis (objective measure) and Voice Handicap Index (VHI, a self-assessment tool). One hundred and forty patients who had thyroid surgery with or without postoperative unilateral vocal cord paralysis (PVCP and NPVCP) were included. The patients were evaluated by the VHI and Dysphonia Severity Index (DSI) tools. VHI scores were significantly higher in PVCP patients than in NPVCP patients. Jitter (%) and shimmer (%) were significantly increased, whereas DSI was significantly decreased in PVCP patients. Receiver operating characteristics curve revealed that VHI scores were associated with the diagnosis of PVCP, of which VHI total score yielded an area under the curve (AUC) of 0.81. Among acoustic parameters, DSI was highly associated to PVCP (AUC=0.82, 95%CI=0.75 to 0.89). Moreover, we found a correlation between VHI scores and voice acoustic parameters. Among them, DSI had a moderate correlation with functional and VHI scores, as suggested by an R value of 0.41 and 0.49, respectively. VHI scores and acoustic parameters were associated with the diagnosis of PVCP.

16.
J Asian Nat Prod Res ; 26(1): 91-101, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38192081

RESUMEN

A new phenolic compound oleiphenol (1), and a new dihydrochalcone oleifechalcone (2) along with seven known compounds (3-9) were isolated from the fruit shell of Camellia oleifera Abel. The planar structures of compounds 1 and 2 were determined on the basis of extensive spectroscopic analyses (IR, UV, NMR, and HR-ESI-MS) and comparison with literature data. The absolute configurations of the new structures were determined by ECD calculations and chemical methods. In addition, compounds 1-9 underwent a series of pharmacological activity tests, including cytotoxic, anti-inflammatory, anti-RSV and antioxidant activities.


Asunto(s)
Camellia , Frutas , Flavonoides/farmacología , Camellia/química , Antioxidantes/farmacología , Antioxidantes/química , Espectroscopía de Resonancia Magnética
17.
Mol Pharm ; 21(2): 454-466, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38232985

RESUMEN

Ovarian cancer, one of the deadliest malignancies, lacks effective treatment, despite advancements in surgical techniques and chemotherapy. Thus, new therapeutic approaches are imperative to improving treatment outcomes. Immunotherapy, which has demonstrated considerable success in managing various cancers, has already found its place in clinical practice. This review aims to provide an overview of ovarian tumor immunotherapy, including its basics, key strategies, and clinical research data supporting its potential. In particular, this discussion highlights promising strategies such as checkpoint inhibitors, vaccines, and pericyte transfer, both individually and in combination. However, the advancement of new immunotherapies necessitates large controlled randomized trials, which will undoubtedly shape the future of ovarian cancer treatment.


Asunto(s)
Vacunas contra el Cáncer , Neoplasias Ováricas , Humanos , Femenino , Inmunoterapia/métodos , Neoplasias Ováricas/tratamiento farmacológico , Resultado del Tratamiento , Vacunas contra el Cáncer/uso terapéutico
18.
Zookeys ; 1188: 251-264, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38239384

RESUMEN

Three new species of the genus Oecleopsis Emeljanov, 1971 from China, O.acerbus Lv & Chen, sp. nov. and O.panxianensis Lv & Chen, sp. nov. from Guizhou Province, and O.digitatus Lv & Chen, sp. nov. from Sichuan Province, are described and illustrated. With these additions, the number of species in the genus is increased to 18. An updated identification key and checklist of all known species of Oecleopsis are provided as well as a map of their geographic distributions.

19.
Biomimetics (Basel) ; 9(1)2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38248603

RESUMEN

The positioning accuracy of spacecraft in orbit is easily affected by low-frequency micro-vibrations of the environment and internal disturbances caused by the payload. Inspired by the neck structure of birds, this study devised a piezo-driven active vibration isolation unit with high stiffness. First, a dynamic model and two-sensor feedback control method for the isolation unit were developed, and the isolation mechanism and anti-disturbance characteristics were analyzed. Further, the stability of the closed-loop was verified. Simulation models of serial and parallel systems based on the proposed vibration isolation unit were implemented to demonstrate its feasibility. The results indicate that the proposed isolation units can provide excellent low-frequency vibration isolation performance and inertial stability and that they can effectively resist the internal disturbance of the payload. Moreover, its performance can be further improved via serial or parallel reconfiguration that facilitates its adaptation to the varied isolation requirements of spacecraft.

20.
Adv Mater ; 36(5): e2308692, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37939356

RESUMEN

Nowadays, the development of wide-bandgap perovskite by thermal evaporation and spin-coating hybrid sequential deposition (HSD) method has special meaning on textured perovskite/silicon tandem solar cells. However, the common issues of insufficient reaction caused by blocking of perovskite capping layer are exacerbated in HSD, because evaporated precursors are usually denser with higher crystallinity and the widely used additive-assisted microstructure is also difficult to access. Here, a facile "diffusible perovskite capping layer" (DPCL) strategy to solve this dilemma is presented. With DPCL, crystallization alleviation of perovskite and more diffusion channels of organic salts can be realized simultaneously, contributing to a homogenization process. The resultant perovskite films exhibit complete conversion, uniform crystallization, enhanced quality, and reduced defect, leading to obvious improvements in device efficiency, repeatability, and stability. This work offers a way to promote the development of textured tandems a step further.

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