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Molecular dynamics simulations are utilized to unravel the temperature-driven phase transition in double-layered butylammonium (BA) methylammonium (MA) lead halide perovskite (BA)2(MA)Pb2I7, which holds great promise for a wide range of optoelectronics and sensor applications. The simulations successfully capture the structural transition from low to high symmetry phases with rising temperatures, consistent with experimental observations. The phase transition is initiated at two critical interfaces: the first is between the inorganic and organic layers, where the melting of N-H bonds in BA leads to a significant reduction in hydrogen bonding between BA and iodides, and the second is at the interface between the top and bottom organic layers, where the melting of the tail bonds in BA triggers the phase transition. Following this, BA cations exhibit a patterned and synchronized motion reminiscent of a conical pendulum, displaying a mix of ordered and disordered behaviors prior to evolving into a completely molten and disordered state. While the melting of BA cations is the primary driver of the phase transition, the rotational dynamics of MA cations also plays a critical role in determining the phase transition temperature, influenced by the BA-MA interaction. Such an interaction alters the polarization patterns of MA cations across the phase transition. In particular, an antiparallel polarization pattern is observed in the low-temperature phase. Additionally, displacive elements of the phase transition are identified in the simulations, characterized by the shear and distortion of the inorganic octahedra. Notably, at lower temperatures, the octahedral distortion follows a bimodal distribution, reflecting significant variations in distortion among octahedra. This variation is attributed to an anisotropic hydrogen bonding network between iodides and BA cations. Our study reveals the phenomena and mechanisms extending beyond the order-disorder transition mechanism, suggesting potential phase engineering through strategic tuning of organic and inorganic components.
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Device-level implementation of soft materials for energy conversion and thermal management demands a comprehensive understanding of their thermal conductivity and elastic modulus to mitigate thermo-mechanical challenges and ensure long-term stability. Thermal conductivity and elastic modulus are usually positively correlated in soft materials, such as amorphous macromolecules, which poses a challenge to discover materials that are either soft and thermally conductive or hard and thermally insulative. Here, we show anomalous correlations of thermal conductivity and elastic modulus in two-dimensional (2D) hybrid organic-inorganic perovskites (HOIP) by engineering the molecular interactions between organic cations. By replacing conventional alkyl-alkyl and aryl-aryl type organic interactions with mixed alkyl-aryl interactions, we observe an enhancement in elastic modulus with a reduction in thermal conductivity. This anomalous dependence provides a route to engineer thermal conductivity and elastic modulus independently and a guideline to search for better thermal management materials. Further, introducing chirality into the organic cation induces a molecular packing that leads to the same thermal conductivity and elastic modulus regardless of the composition across all half-chiral 2D HOIPs. This finding provides substantial leeway for further investigations in chiral 2D HOIPs to tune optoelectronic properties without compromising thermal and mechanical stability.
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Traditional Chinese Medicines (TCMs) have been used for centuries for the treatment and management of various diseases. However, their effective delivery to targeted sites may be a major challenge due to their poor water solubility, low bioavailability, and potential toxicity. Nanocarriers, such as liposomes, polymeric nanoparticles, inorganic nanoparticles and organic/inorganic nanohybrids based on active constituents from TCMs have been extensively studied as a promising strategy to improve the delivery of active constituents from TCMs to achieve a higher therapeutic effect with fewer side effects compared to conventional formulations. This review summarizes the recent advances in nanocarrier-based delivery systems for various types of active constituents of TCMs, including terpenoids, polyphenols, alkaloids, flavonoids, and quinones, from different natural sources. This review covers the design and preparation of nanocarriers, their characterization, and in vitro/vivo evaluations. Additionally, this review highlights the challenges and opportunities in the field and suggests future directions for research. Nanocarrier-based delivery systems have shown great potential in improving the therapeutic efficacy of TCMs, and this review may serve as a comprehensive resource to researchers in this field.
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Medicamentos Herbarios Chinos , Nanopartículas , Medicamentos Herbarios Chinos/farmacología , Medicina Tradicional China , Disponibilidad Biológica , Nanotecnología , Sistemas de Liberación de MedicamentosRESUMEN
Chiral hybrid metal-halide semiconductors (MHS) pose as ideal candidates for spintronic applications owing to their strong spin-orbit coupling (SOC), and long spin relaxation times. Shedding light on the underlying structure-property relationships is of paramount importance for the targeted synthesis of materials with an optimum performance. Herein, we report the synthesis and optical properties of 1D chiral (R-/S-THBTD)SbBr5 (THBTD = 4,5,6,7-tetrahydro-benzothiazole-2,6-diamine) semiconductors using a multifunctional ligand as a countercation and a structure directing agent. (R-/S-THBTD)SbBr5 feature direct and indirect band gap characteristics, exhibiting photoluminescence (PL) light emission at RT that is accompanied by a lifetime of a few ns. Circular dichroism (CD), second harmonic generation (SHG), and piezoresponse force microscopy (PFM) studies validate the chiral nature of the synthesized materials. Density functional theory (DFT) calculations revealed a Rashba/Dresselhaus (R/D) spin splitting, supported by an energy splitting (ER) of 23 and 25 meV, and a Rashba parameter (αR) of 0.23 and 0.32 eV·Å for the R and S analogs, respectively. These values are comparable to those of the 3D and 2D perovskite materials. Notably, (S-THBTD)SbBr5 has been air-stable for a year, a record performance among chiral lead-free MHS. This work demonstrates that low-dimensional, lead-free, chiral semiconductors with exceptional air stability can be acquired, without compromising spin splitting and manipulation performance.
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In this work, we investigated the effect of hole transporting poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) interfacing with Mn-doped CdS/ZnS quantum dots (QDs) deposited on an indium tin oxide (ITO) substrate on the photoemission of upconverted hot electrons under weak continuous wave photoexcitation in a vacuum. Among the various factors that can influence the photoemission of the upconverted hot electrons, we studied the role of PEDOT:PSS in facilitating the hole transfer from QDs and altering the energy of photoemitted hot electrons. Compared to hot electrons emitted from QDs deposited directly on the ITO substrate, the addition of the PEDOT:PSS layer between the QD and ITO layers increased the energy of the photoemitted hot electrons. The increased energy of the photoemitted hot electrons is attributed in part to the reduced steady-state positive charge on the QDs under continuous photoexcitation, which reduces the energy required to eject the electron from the conduction band.
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Ladder-type structures can impart exceptional stability to polymeric electronic materials. This article introduces a new class of conductive polymers featuring a fully ladder-type backbone. A judicious molecular design strategy enables the synthesis of a low-defect ladder polymer, which can be efficiently oxidized and acid-doped to achieve its conductive state. The structural elucidation of this polymer and the characterization of its open-shell nature are facilitated with the assistance of studies on small molecular models. An autonomous robotic system is used to optimize the conductivity of the polymer thin film, achieving over 7 mS cm-1. Impressively, this polymer demonstrates unparalleled stability in strong acid and under harsh UV-irradiation, significantly surpassing commercial benchmarks like PEDOT:PSS and polyaniline. Moreover, it displays superior durability across numerous redox cycles as the active material in an electrochromic device and as the pseudocapacitive material in a supercapacitor device. This work provides structural design guidance for durable conductive polymers for long-term device operation.
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2D hybrid organic-inorganic perovskites (HOIPs) are commonly found under subcritical cyclic stresses and suffer from fatigue issues during device operation. However, their fatigue properties remain unknown. Here, the fatigue behavior of (C4 H9 -NH3 )2 (CH3 NH3 )2 Pb3 I10 , the archetype 2D HOIP, is systematically investigated by atomic force microscopy (AFM). It is found that 2D HOIPs are much more fatigue resilient than polymers and can survive over 1 billion cycles. 2D HOIPs tend to exhibit brittle failure at high mean stress levels, but behave as ductile materials at low mean stress levels. These results suggest the presence of a plastic deformation mechanism in these ionic 2D HOIPs at low mean stress levels, which may contribute to the long fatigue lifetime, but is inhibited at higher mean stresses. The stiffness and strength of 2D HOIPs are gradually weakened under subcritical loading, potentially as a result of stress-induced defect nucleation and accumulation. The cyclic loading component can further accelerate this process. The fatigue lifetime of 2D HOIPs can be extended by reducing the mean stress, stress amplitude, or increasing the thickness. These results can provide indispensable insights into designing and engineering 2D HOIPs and other hybrid organic-inorganic materials for long-term mechanical durability.
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As an emerging environmental pollutant, microplastics have attracted much attention, but the sources and health hazards of atmospheric microplastics (AMPs) remain unclear. In order to explore the distribution characteristics, assess the risk of human respiratory exposure, and analyze the sources of AMPs in different functional areas of Yichang City, AMPs samples from 16 observation points were collected and analyzed, and the HYSPLIT model was used. The results showed that the main shapes of AMPs in Yichang City were fiber, fragment, and film, and six colors were observed including transparent, red, black, green, yellow, and purple. The smallest size was 10.42 µm, and the largest was 4761.42 µm. The deposition flux of AMPs was (4400±474) n·(m2·d)-1. The types of APMs were polyester fiber (PET), acrylonitrile-butadiene-styrene copolymer (ABS), polyamide (PA), rubber (Rubber), polyethylene (PE), cellulose acetate (CA), and polyacrylonitrile (PAN). The order of the subsidence flux in each functional area was as follows:urban residential area>agricultural production area>landfill>chemical industrial park>town residential area. The human respiratory exposure risk assessment models showed that the daily intake of AMPs (EDI) for adults and children in urban residential areas was higher than in town residential areas. The atmospheric backward trajectory simulation showed that the AMPs in the districts and counties of Yichang City mainly came from the surrounding areas via short-distance transportation. This study provided basic data support for the research on AMPs in the middle reaches of the Yangtze River and was of great significance for the traceability and health risk research of AMPs pollution.
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Acrilonitrilo , Microplásticos , Adulto , Niño , Humanos , Plásticos , Goma , AgriculturaRESUMEN
Objective: The purpose of this study was to evaluate the efficacy and safety of Zishen Yutai Pill combined with western medicine for the treatment of women with threatened miscarriage during the first trimester of pregnancy. Methods: Randomized controlled trials published before the end of Apr 1, 2023 on Zishen Yutai Pill and threatened miscarriage were systematically retrieved from China National Knowledge Infrastructure, Wanfang, Sinomed, VIP, PubMed, EMBASE, Web of Science and the Cochrane Library. The international clinical trial registration platform and the Chinese clinical trial registration platform of clinical trials was searched from their inception until Apr 1, 2023. Meta analysis of random effect model was used to combine the research data. Chi-squared test and I2 statistics were used for heterogeneity test. Results: Twenty-three trials (enrolling 2411 participants) were included in the review. Zishen Yutai pill combined with western medicine therapy showed significant improvement on human chorionic gonadotropin [MD 19.33 IU/ml, 95% CI (15.84, 22.81)], the total effective rate [RR 1.19, 95% CI (1.15-1.23)], progesterone [MD 7.14 ng/ml, 95% CI (6.14, 8.13)], estradiol [MD 33.69 pg/ml, 95% CI (27.42, 39.96)], duration of abdominal pain [MD -2.36 d, 95% CI (- 3.54, - 1.18)], duration of vaginal bleeding [MD -1.94 d, 95% CI (- 2.93, - 0.94)], and fibrinogen [MD -0.34 g/L, 95% CI (- 0.57, - 0.11)]. There was no significant difference in hematocrit [MD 0.68%, 95% CI (- 0.08, 1.44)] between the experimental and the control group. Zishen Yutai Pill may improve the clinical symptoms in women with threatened miscarriage, such as human chorionic gonadotropin the total effective rate, progesterone, estradiol, duration of abdominal pain, duration of vaginal bleeding, and fibrinogen. Especially for progesterone, the effect of treatment â¦2 weeks is significantly better than treatment of >2 weeks. For estradiol, the effect of treatment >2 weeks is significantly better than treatment of ⦠2 weeks. Conclusion: Zishen Yutai Pill, as a complementary therapy, significantly improved human chorionic gonadotropin, the total effective rate, progesterone, estradiol, abdominal pain, vaginal bleeding, and fibrinogen in patients with threatened miscarriage in first-trimester pregnancy. However, the systematic review has some limitations, such as degraded information quality, no blinding of patients or doctors, etc. Due to the small sample size and low quality of research, it needs to be further confirmed by large sample and high-quality randomized controlled trials, such as blinding of patients, doctors and outcome assessment should be complemented, clinical follow-up, live birth rate, fetal growth should be supplemented. Systematic review registration: INPLASY202320039.
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Background: Neutrophil extracellular traps (NETs) can cause acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) by inducing macrophage pyroptosis. The purpose of this study was to find out whether pretreatment of alpha-linolenic acid (ALA) could inhibit NETs-induced macrophage pyroptosis in sepsis-induced ALI/ARDS, as well as to identify which inflammasome is involved in this process. Methods: LPS was instilled into the trachea to establish sepsis-induced ALI/ARDS in a mouse model. âLung injury was assessed by microscopic examination of lung tissue after hematoxylin and eosin staining, pathology score, and bronchoalveolar lavage fluid (BALF) total protein concentration. The level of NETs in lung tissue was detected by MPO-DNA ELISA. Purified NETs, extracted from peritoneal neutrophils, induced macrophage pyroptosis in vitro. Expression of pyroptosis-related proteins (Cl-caspase-1, Cl-GSDMD, ASC) and IL-1ß in the lung tissue and bone marrow-derived macrophages (BMDMs) were determined by western blotting or ELISA. Specks of Pyrin/ASC were examined by confocal immunofluorescence microscopy. Mefv (Pyrin)-/- mice were used to study the role of Pyrin in the process of sepsis-induced ALI/ARDS. Results: ALA alleviated LPS-induced lung injury. ALA reduced the level of NETs, pyroptosis-related proteins (Cl-caspase-1, Cl-GSDMD, ASC), and IL-1ß in the lung tissue of sepsis mice. In vitro, NETs increased the expression of pyroptosis-related proteins (Cl-caspase-1, Cl-GSDMD, ASC) and IL-1ß significantly in BMDMs. Pyrin protein was found to be higher and form the inflammasome with ASC in NETs challenged-BMDMs. Knockout of Mefv (Pyrin) gene fully restored the increased expression of pyroptosis-related proteins (Cl-caspase-1, Cl-GSDMD, ASC) and IL-1ß in vitro and in vivo. Lung injury was alleviated significantly in Mefv (Pyrin)-/- mice as well.â ALA suppresses all the NETs-induced changes as mentioned above. Conclusion: Our study is the first to demonstrate Pyrin inflammasome driving NETs-induced macrophage pyroptosis, and ALA may reduce ALI/ARDS by inhibiting the activation of the Pyrin inflammasome-driven macrophage pyroptosis.
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Lesión Pulmonar Aguda , Trampas Extracelulares , Síndrome de Dificultad Respiratoria , Sepsis , Animales , Ratones , Inflamasomas/metabolismo , Macrófagos Alveolares/metabolismo , Pirina , Ácido alfa-Linolénico , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Trampas Extracelulares/metabolismo , Piroptosis , Lipopolisacáridos/farmacología , Lesión Pulmonar Aguda/metabolismo , Ratones Noqueados , Síndrome de Dificultad Respiratoria/patología , Sepsis/complicaciones , Sepsis/patología , CaspasasRESUMEN
Ionizing radiation such as X-rays and γ-rays has been extensively studied and used in various fields such as medical imaging, radiographic nondestructive testing, nuclear defense, homeland security, and scientific research. Therefore, the detection of such high-energy radiation with high-sensitivity and low-cost-based materials and devices is highly important and desirable. Halide perovskites have emerged as promising candidates for radiation detection due to the large light absorption coefficient, large resistivity, low leakage current, high mobility, and simplicity in synthesis and processing as compared with commercial silicon (Si) and amorphous selenium (a-Se). In this review, we provide an extensive overview of current progress in terms of materials development and corresponding device architectures for radiation detection. We discuss the properties of a plethora of reported compounds involving organic-inorganic hybrid, all-inorganic, all-organic perovskite and antiperovskite structures, as well as the continuous breakthroughs in device architectures, performance, and environmental stability. We focus on the critical advancements of the field in the past few years and we provide valuable insight for the development of next-generation materials and devices for radiation detection and imaging applications.
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The implementation of two-dimensional (2D) hybrid organic-inorganic perovskites (HOIPs) in semiconductor device applications will have to accommodate the co-existence of strain and temperature stressors and requires a thorough understanding of the thermomechanical behavior of 2D HOIPs. This will mitigate thermomechanical stability issues and improve the durability of the devices, especially when one considers the high susceptibility of 2D HOIPs to temperature due to their soft nature. Here, we employ atomic force microscopy (AFM) stretching of suspended membranes to measure the temperature dependence of the in-plane Young's modulus (Eâ¥) of model Ruddlesden-Popper 2D HOIPs with a general formula of (CH3(CH2)3NH3)2(CH3NH3)n-1PbnI3n+1 (here, n = 1, 3, or 5). We find that E⥠values of these 2D HOIPs exhibit a prominent non-monotonic dependence on temperature, particularly an abnormal thermal stiffening behavior (nearly 40% change in Eâ¥) starting around the order-disorder transition temperature of the butylammonium spacer molecules, which is significantly different from the thermomechanical behavior expected from their 3D counterpart (CH3NH3PbI3) or other low-dimensional material systems. Further raising the temperature eventually reverses the trend to thermal softening. The magnitude of the thermally induced change in E⥠is also much higher in 2D HOIPs than in their 3D analogs. Our results can shed light on the structural origin of the thermomechanical behavior and provide needed guidance to design 2D HOIPs with desired thermomechanical properties to meet the application needs.
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Modifiers are commonly used in natural, biological, and synthetic crystallization to tailor the growth of diverse materials. Here, we identify tautomers as a new class of modifiers where the dynamic interconversion between solute and its corresponding tautomer(s) produces native crystal growth inhibitors. The macroscopic and microscopic effects imposed by inhibitor-crystal interactions reveal dual mechanisms of inhibition where tautomer occlusion within crystals that leads to natural bending, tunes elastic modulus, and selectively alters the rate of crystal dissolution. Our study focuses on ammonium urate crystallization and shows that the keto-enol form of urate, which exists as a minor tautomer, is a potent inhibitor that nearly suppresses crystal growth at select solution alkalinity and supersaturation. The generalizability of this phenomenon is demonstrated for two additional tautomers with relevance to biological systems and pharmaceuticals. These findings offer potential routes in crystal engineering to strategically control the mechanical or physicochemical properties of tautomeric materials.
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Interactions between the microbiota and their colonized environments mediate critical pathways from biogeochemical cycles to homeostasis in human health. Here we report a soil-inspired chemical system that consists of nanostructured minerals, starch granules and liquid metals. Fabricated via a bottom-up synthesis, the soil-inspired chemical system can enable chemical redistribution and modulation of microbial communities. We characterize the composite, confirming its structural similarity to the soil, with three-dimensional X-ray fluorescence and ptychographic tomography and electron microscopy imaging. We also demonstrate that post-synthetic modifications formed by laser irradiation led to chemical heterogeneities from the atomic to the macroscopic level. The soil-inspired material possesses chemical, optical and mechanical responsiveness to yield write-erase functions in electrical performance. The composite can also enhance microbial culture/biofilm growth and biofuel production in vitro. Finally, we show that the soil-inspired system enriches gut bacteria diversity, rectifies tetracycline-induced gut microbiome dysbiosis and ameliorates dextran sulfate sodium-induced rodent colitis symptoms within in vivo rodent models.
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Colitis , Microbioma Gastrointestinal , Humanos , Animales , Suelo/química , Colitis/inducido químicamente , Colitis/metabolismo , Homeostasis , Modelos Animales de EnfermedadRESUMEN
Demands for high-performance electrical power transmission cables continue to rise, especially for offshore power transmission, electric vehicles, portable electronics, and deployable military applications. Carbon nanotubes (CNTs)-Copper (Cu) core-shell wire is regarded as one of the best candidate material systems for transmitting electricity and thermal energy. In this study, a facile and robust approach was developed to enhance the CNT-Cu interfacial interactions. This approach consists of a substrate-enhanced electroless deposition step for Cu pre-seeding and thiol functionalization. Benefiting from the thiol-activated CNT surface and Cu seed deposit, the CNTs-Cu core-shell wire forms a densely packed Cu shell with a void-free CNT-Cu interface. Consequently, the CNTs-Cu core-shell wire possesses (1) superior specific strength (eightfold stronger), (2) 30% higher specific conductivity, (3) 120% higher specific ampacity, and (4) an impressive 110% higher thermal conductivity compared with pure Cu wires. Moreover, this composite wire still maintains its structural integrity and electrical properties over 600 cycles of the fatigue bending test, rendering this system an excellent candidate for high-performance electrical cable and conductor applications.
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BACKGROUND: Mitochondrial DNA (mtDNA) is a potent activator for pro-inflammatory response. Dendritic cells (DCs) are immunosuppressed in sepsis, whether mtDNA mediates immunoparalysis in sepsis remains unknown. METHODS: The mRNAs were assessed by qPCR. Flow cytometry was used to measure the expression of costimulatory molecules and the proliferation of CD4+ T cells. Western blot and immunofluorescence staining were used to analyse the expression of proteins. Cytokine secretion was detected by ELISA. Histology of lung tissue was used to assess the inflammatory injury. RESULTS: Lipopolysaccharide-induced endotoxemia increased plasma mtDNA levels and immunoparalysis of spleen DCs, while hydrolysing mtDNA reversed immunoparalysis of spleen DCs in vivo. Moreover, cytoplasmic mtDNA of DCs was accumulated in endotoxemia and sepsis. mtDNA transfection into bone marrow-derived DCs (BMDCs) inhibited the expression of costimulatory molecules (e.g., CD40, CD80 and CD86) and the release of IL-12p70, while increasing the secretion of IL-10. Cytoplasmic mtDNA also inhibited the ability of BMDCs to promote the proliferation of CD4+ T cells. Mechanistic analysis revealed that STING signalling was required for mtDNA-mediated immunoparalysis of DCs in vivo and in vitro. Further studies showed deletion of STING reversed mtDNA-mediated immunoparalysis of DCs and improved the prognosis of endotoxemia and sepsis. CONCLUSION: Our results demonstrated that mtDNA promotes immunoparalysis of DCs, and contributes to sepsis-associated immunosuppression by activating STING signalling. Our study may provide new insights to elucidate the molecular pathogenesis of immunosuppressive DCs in sepsis.
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Endotoxemia , Sepsis , Humanos , Células Dendríticas/metabolismo , ADN Mitocondrial/genética , ADN Mitocondrial/metabolismo , Endotoxemia/metabolismo , BazoRESUMEN
Robots with submillimeter dimensions are of interest for applications that range from tools for minimally invasive surgical procedures in clinical medicine to vehicles for manipulating cells/tissues in biology research. The limited classes of structures and materials that can be used in such robots, however, create challenges in achieving desired performance parameters and modes of operation. Here, we introduce approaches in manufacturing and actuation that address these constraints to enable untethered, terrestrial robots with complex, three-dimensional (3D) geometries and heterogeneous material construction. The manufacturing procedure exploits controlled mechanical buckling to create 3D multimaterial structures in layouts that range from arrays of filaments and origami constructs to biomimetic configurations and others. A balance of forces associated with a one-way shape memory alloy and the elastic resilience of an encapsulating shell provides the basis for reversible deformations of these structures. Modes of locomotion and manipulation span from bending, twisting, and expansion upon global heating to linear/curvilinear crawling, walking, turning, and jumping upon laser-induced local thermal actuation. Photonic structures such as retroreflectors and colorimetric sensing materials support simple forms of wireless monitoring and localization. These collective advances in materials, manufacturing, actuation, and sensing add to a growing body of capabilities in this emerging field of technology.
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Robótica , Materiales Inteligentes , Biomimética , Locomoción , CaminataRESUMEN
The nature of the organic cation in two-dimensional (2D) hybrid lead iodide perovskites tailors the structural and technological features of the resultant material. Herein, we present three new homologous series of (100) lead iodide perovskites with the organic cations allylammonium (AA) containing an unsaturated CâC group and iodopropylammonium (IdPA) containing iodine on the organic chain: (AA)2MAn-1PbnI3n+1 (n = 3-4), [(AA)x(IdPA)1-x]2MAn-1PbnI3n+1 (n = 1-4), and (IdPA)2MAn-1PbnI3n+1 (n = 1-4), as well as their perovskite-related substructures. We report the in situ transformation of AA organic layers into IdPA and the incorporation of these cations simultaneously into the 2D perovskite structure. Single-crystal X-ray diffraction shows that (AA)2MA2Pb3I10 crystallizes in the space group P21/c with a unique inorganic layer offset (0, <1/2), comprising the first example of n = 3 halide perovskite with a monoammonium cation that deviates from the Ruddlesden-Popper (RP) halide structure type. (IdPA)2MA2Pb3I10 and the alloyed [(AA)x(IdPA)1-x]2MA2Pb3I10 crystallize in the RP structure, both in space group P21/c. The adjacent I···I interlayer distance in (AA)2MA2Pb3I10 is â¼5.6 Å, drawing the [Pb3I10]4- layers closer together among all reported n = 3 RP lead iodides. (AA)2MA2Pb3I10 presents band-edge absorption and photoluminescence (PL) emission at around 2.0 eV that is slightly red-shifted in comparison to (IdPA)2MA2Pb3I10. The band structure calculations suggest that both (AA)2MA2Pb3I10 and (IdPA)2MA2Pb3I10 have in-plane effective masses around 0.04m0 and 0.08m0, respectively. IdPA cations have a greater dielectric contribution than AA. The excited-state dynamics investigated by transient absorption (TA) spectroscopy reveal a long-lived (â¼100 ps) trap state ensemble with broad-band emission; our evidence suggests that these states appear due to lattice distortions induced by the incorporation of IdPA cations.
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Sepsis is a heterogeneous syndrome induced by a dysregulated host response to infection. Glycolysis plays a role in maintaining the immune function of macrophages, which is crucial for severely septic patients. However, how the pathways that link glycolysis and macrophages are regulated is still largely unknown. Here, we provide evidence to support the function of KLF14, a novel Krüppel-like transcription factor, in the regulation of glycolysis and the immune function of macrophages during sepsis. KLF14 deletion led to significantly increased mortality in lethal models of murine endotoxemia and sepsis. Mechanistically, KLF14 decreased glycolysis and the secretion of inflammatory cytokines by macrophages by inhibiting the transcription of HK2. In addition, we confirmed that the expression of KLF14 was upregulated in septic patients. Furthermore, pharmacological activation of KLF14 conferred protection against sepsis in mice. These findings uncover a key role of KLF14 in modulating the inflammatory signaling pathway and shed light on the development of KLF14-targeted therapeutics for sepsis.