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Manganese halides are one of the most potential candidates for large-area flat-panel detection owing to their biological safety and all-solution preparation. However, reducing photon scattering and enhancing the efficient luminescence of scintillator screens remains a challenge due to their uncontrollable crystallization and serious nonradiative recombination. Herein, an organic cation modulation is reported to control the crystallization process and enhance the luminescence properties of manganese halides. Given the industrial requirements of the X-ray flat-panel detector, the large-area A2MnBr4 screen (900 cm2) with excellent uniformity is blade-coated at 60 °C. Theoretical calculations and in situ measurements reveal that organic cations with larger steric hindrance can slow down the crystallization of the screen, thus neatening the crystal arrangement and reducing the photon scattering. Moreover, larger steric hindrance can also endow the material with higher exciton binding energy, which is beneficial for restraining nonradiative recombination. Therefore, the BPP2MnBr4 (BPP = C25H22P+) screen with larger steric hindrance exhibits a superior spatial resolution (>20 lp mm-1) and ultra-low detection limit (< 250 nGyair s-1). This is the first time steric hindrance modulation is used in blade-coated scintillator screens, and it believes this study will provide some guidance for the development of high-performance manganese halide scintillators.
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Metal-free perovskites (MFPs) have recently become a newcomer in X-ray detection due to their flexibility and low toxicity characteristics. However, their photoelectronic properties and stability should be further improved mainly through materials design. Here, the aminoazanium of DABCO2+ was developed for the preparation of NDABCO-NH4Br3 (NDABCO = N-amino-N'-diazabicyclo[2.2.2]octonium) single crystals (SCs), and its physical properties, intermolecular interactions, and device performance were systematically explored. Notably, NDABCO-NH4Br3 can achieve improved stability by enlarging defect formation energy and inducing abundant intermolecular forces. Moreover, the slight lattice distortion could ensure the weakening electron-phonon coupling for improving carrier transport. In particular, the slight lattice distortion after the long-chain NDABCO2+ introduction could retard thermal expansion for the preparation of high-quality crystals. Finally, the corresponding X-ray detector delivered a moderate sensitivity of 623.3 µC Gyair-1 cm-2. This work provides a novel strategy through rationally designed organic cations to balance the material stability and device performance.
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Despite extensive research on the photoluminescence properties of Bi3+ ions, the origins of their emission and excitation bands remain elusive. Herein, we present a comprehensive analysis of the photoluminescence properties of Bi3+-activated LuXnGaO4 (Xn = Mg, Zn), elucidating the underlying factors governing the intra-ionic and extra-ionic electronic transitions. By integrating crystal structure data and spectroscopic data analyses with semi-empirical formula calculations, the origins of excitation and emission states were elucidated. Moreover, the impact of alterations in chemical surroundings on the luminescence of Bi3+ was investigated. Both LuXnGaO4:Bi3+ phosphors exhibit three excitation peaks in the near ultraviolet region and display a broadband yellow emission. However, the luminous behavior of LuMgGaO4:Bi3+ and LuZnGaO4:Bi3+ differs due to variations in the band gap, bond length and neighboring atoms. It is anticipated that the investigation of Bi3+-activated gallates presents a promising avenue for advancing wide-band and long-wavelength emitting phosphors.
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The dorsomedial posterior parietal cortex (dmPPC) is part of a higher-cognition network implicated in elaborate processes underpinning memory formation, recollection, episode reconstruction, and temporal information processing. Neural coding for complex episodic processing is however under-documented. Here, we recorded extracellular neural activities from three male rhesus macaques (Macaca mulatta) and revealed a set of neural codes of "neuroethogram" in the primate parietal cortex. Analyzing neural responses in macaque dmPPC to naturalistic videos, we discovered several groups of neurons that are sensitive to different categories of ethogram items, low-level sensory features, and saccadic eye movement. We also discovered that the processing of category and feature information by these neurons is sustained by the accumulation of temporal information over a long timescale of up to 30â s, corroborating its reported long temporal receptive windows. We performed an additional behavioral experiment with additional two male rhesus macaques and found that saccade-related activities could not account for the mixed neuronal responses elicited by the video stimuli. We further observed monkeys' scan paths and gaze consistency are modulated by video content. Taken altogether, these neural findings explain how dmPPC weaves fabrics of ongoing experiences together in real time. The high dimensionality of neural representations should motivate us to shift the focus of attention from pure selectivity neurons to mixed selectivity neurons, especially in increasingly complex naturalistic task designs.
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Neurônios , Movimentos Sacádicos , Animais , Masculino , Macaca mulatta , Neurônios/fisiologia , Cognição , Lobo Parietal/fisiologiaRESUMO
Information-processing devices are the core components of modern electronics. Integrating them into textiles is the indispensable demand for electronic textiles to form close-loop functional systems. Memristors with crossbar configuration are regarded as promising building blocks to design woven information-processing devices that seamlessly unify with textiles. However, the memristors always suffer from severe temporal and spatial variations due to the random growth of conductive filaments during filamentary switching processes. Here, inspired by the ion nanochannels across synaptic membranes, a highly reliable textile-type memristor made of Pt/CuZnS memristive fiber with aligned nanochannels, showing small set voltage variation (<5.6%) under ultralow set voltage (≈0.089 V), high on/off ratio (≈106 ), and low power consumption (0.1 nW), is reported. Experimental evidence indicate that nanochannels with abundant active S defects can anchor silver ions and confine their migrations to form orderly and efficient conductive filaments. Such memristive performances enable the resultant textile-type memristor array to have high device-to-device uniformity and process complex physiological data like brainwave signals with high recognition accuracy (95%). The textile-type memristor arrays are mechanically durable to withstand hundreds of bending and sliding deformations, and seamlessly unified with sensing, power-supplying, and displaying textiles/fibers to form all-textile integrated electronic systems for new generation human-machine interactions.
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Hydrotalcite, first found in natural ores, has important applications in supercapacitors. NiCoAl-LDH, as a hydrotalcite-like compound with good crystallinity, is commonly synthesized by a hydrothermal method. Al3+ plays an important role in the crystallization of hydrotalcite and can provide stable trivalent cations, which is conducive to the formation of hydrotalcite. However, aluminum and its hydroxides are unstable in a strong alkaline electrolyte; therefore, a secondary alkali treatment is proposed in this work to produce cation vacancies. The hydrophilicity of the NiCoAl-OH surface with cation vacancy has been greatly improved, which is conducive to the wetting and infiltration of electrolyte in water-based supercapacitors. At the same time, cation vacancies generate a large number of defects as active sites for energy storage. As a result, the specific capacity of the NiCoAl-OH electrode after 10,000 cycles can be maintained at 94.1%, which is much better than the NiCoAl-LDH material of 74%.
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Developing optical thermometer phosphors with high sensitivity, high signal discriminability and strong fluorescence intensity is ongoing. A dual-emitting thermochromic phosphor, LiScSiO4:Ce3+, Tb3+, was successfully synthesized via solid-state reaction method. The crystal structure, electronic structure, luminescent performance and thermal luminescence behaviors as well as the luminescence mechanism of LiScSiO4:Ce3+, Tb3+ were systematically investigated. Due to the energy transfer and different thermoluminescence behaviors between Ce3+ and Tb3+, high relative sensitivity (2.2 % K-1@473 K), excellent signal discriminability (5747 cm-1), outstanding temperature resolution (0.067 K) and good repeatability, as well as efficient emission at high temperatures were achieved based on the fluorescence intensity ratio of Ce3+ and Tb3+, indicating its potential in ratiometric optical thermometer. Moreover, the excellent visualizing thermochromic enable LiScSiO4:Ce3+, Tb3+ to be used as safety sign in variable temperature environment to monitor temperature distribution.
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Neuromorphic computing memristors are attractive to construct low-power- consumption electronic textiles due to the intrinsic interwoven architecture and promising applications in wearable electronics. Developing reconfigurable fiber-based memristors is an efficient method to realize electronic textiles that capable of neuromorphic computing function. However, the previously reported artificial synapse and neuron need different materials and configurations, making it difficult to realize multiple functions in a single device. Herein, a textile memristor network of Ag/MoS2/HfAlOx/carbon nanotube with reconfigurable characteristics was reported, which can achieve both nonvolatile synaptic plasticity and volatile neuron functions. In addition, a single reconfigurable memristor can realize integrate-and-fire function, exhibiting significant advantages in reducing the complexity of neuron circuits. The firing energy consumption of fiber-based memristive neuron is 1.9 fJ/spike (femtojoule-level), which is at least three orders of magnitude lower than that of the reported biological and artificial neuron (picojoule-level). The ultralow energy consumption makes it possible to create an electronic neural network that reduces the energy consumption compared to human brain. By integrating the reconfigurable synapse, neuron and heating resistor, a smart textile system is successfully constructed for warm fabric application, providing a unique functional reconfiguration pathway toward the next-generation in-memory computing textile system.
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Eletrônica , Têxteis , Humanos , Sinapses , Plasticidade Neuronal , Neurônios , Fibras na DietaRESUMO
Developing nitridosilicate red phosphors under mild synthesis conditions is important for regulating the emission quality of white light-emitting diodes (WLEDs). Based on the thermodynamic theory and crystal structure chemistry for the synthesis of nitridosilicates, the Gibbs free energy variation of a hybrid system can be made more negative by reducing the proportion of Si3N4 and increasing the proportion of M2N3 and AlN, enabling the formation of new nitridosilicates under mild conditions. Therefore, a general chemical formula MxSiyAlzNk was proposed for the design of nitridosilicate red phosphors prepared under mild conditions, where M is an alkaline earth metal ion; x > y; z ≥ y; 1 ≤ y ≤ 3; x + 2y = 3n + 3; k - z = 2n + 2; and n is a positive integer. Therefore, in this study, we successfully synthesized the nitridoalumosilicate red phosphor Ca4SiAl3N7:Eu2+ at normal pressure and lower temperature (1350 °C). Under excitation with 460 nm blue light, the Ca4SiAl3N7:Eu2+ phosphor efficiently emits red light at 645 nm and exhibits excellent thermal stability. The crystal structure and luminescence properties of Ca4SiAl3N7:Eu2+ were investigated in detail. The results indicate that Ca4SiAl3N7:Eu2+ exhibits strong potential for use in WLEDs. The design of nitridoalumosilicate red phosphors synthesized under mild conditions based on Gibbs free energy variation provides a new idea for the development of new nitride phosphors.
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Upconversion materials have numerous potential applications in light energy utilization due to their unique optical properties. The use of visible light excitation to obtain ultraviolet emission is a promising technology with broad application prospects, while relevant research is absent. A series of Pr3+, Gd3+ doped Y7O6F9 phosphors were synthesized by traditional solid-state reaction. X-ray diffraction, scanning electronic microscopy, steady-state photoluminescence spectra, a decay dynamic, and upconversion emission spectra of the samples were studied. Under the excitation of 238 nm, the energy transfer from Pr3+ to Gd3+ was realized and a strong ultraviolet B emission due to the 6P7/2â8S7/2 transition of the Gd3+ ions was achieved. Under the excitation of a 450 nm blue laser, Pr3+ absorbed two blue photons to realize the upconversion process and then transferred the energy to Gd3+ to obtain the ultraviolet B emission.
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Background: Pulmonary arterial hypertension (PAH) is a devastating cardio-pulmonary vascular disease in which chronic elevated pulmonary arterial pressure and pulmonary vascular remodeling lead to right ventricular failure and premature death. However, the exact molecular mechanism causing PAH remains unclear. Methods: RNA sequencing was used to analyze the transcriptional profiling of controls and rats treated with monocrotaline (MCT) for 1, 2, 3, and 4 weeks. Weighted gene co-expression network analysis (WGCNA) was employed to identify the key modules associated with the severity of PAH. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed to explore the potential biological processes and pathways of key modules. Real-time PCR and western blot analysis were used to validate the gene expression. The hub genes were validated by an independent dataset obtained from the Gene Expression Omnibus database. Results: A total of 26 gene modules were identified by WGCNA. Of these modules, two modules showed the highest correlation with the severity of PAH and were recognized as the key modules. GO analysis of key modules showed the dysregulated inflammation and immunity, particularly B-cell-mediated humoral immunity in MCT-induced PAH. KEGG pathway analysis showed the significant enrichment of the B-cell receptor signaling pathway in the key modules. Pathview analysis revealed the dysregulation of the B-cell receptor signaling pathway in detail. Moreover, a series of humoral immune response-associated genes, such as BTK, BAFFR, and TNFSF4, were found to be differentially expressed in PAH. Additionally, five genes, including BANK1, FOXF1, TLE1, CLEC4A1, and CLEC4A3, were identified and validated as the hub genes. Conclusion: This study identified the dysregulated B-cell receptor signaling pathway, as well as novel genes associated with humoral immune response in MCT-induced PAH, thereby providing a novel insight into the molecular mechanisms underlying inflammation and immunity and therapeutic targets for PAH.
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Currently, the efficient way to synthesize white light-emitting diodes (WLEDs) is combining a near-ultraviolet (n-UV, 380-420 nm) emitting LED chip with tricolor (red, green, and blue) emitting phosphors. However, further improving the color rendering index (CRI) for WLEDs is hindered by the absence of cyan components. Hence, a series of high-efficiency and continuously tunable Ce3+,Gd3+-doped CaScBO4 (CSBO) blue-cyan phosphors with an orthorhombic structure were successfully developed by a high-temperature solid-state reaction method. Based on density-functional theory (DFT) calculation, a vacancy was produced along with inequivalent replacement (3Ca2+ â 2Ce3+/Gd3+ + V''Ca) when just adding the trivalent cations, meanwhile causing the local environment of the lattice to relax so Ce3+/Gd3+ ions find it easier to enter into Sc3+ sites at a higher doping concentration. Under the excitation of n-UV, the emission peak position moves from 443 nm to 480 nm and two concentration quenching points appear with an increase in Ce3+ ions by defect-induced site-selective occupation. The two samples at concentration quenching points both have high quantum efficiencies of 88.6% and 86.2% and an acceptable thermal quenching performance. The property performance and internal mechanism are illuminated by the excitation and emission spectra and theoretical analysis. Finally, by combining CSBO:Ce3+, commercial green and red phosphors and an n-UV LED chip, an as-fabricated WLED with a great CRI value of 93.2 and a low CCT (4291K) was obtained. This work demonstrates the potential of CSBO:Ce3+ as a blue-cyan phosphor for use in high-quality full-visible-spectrum WLEDs in the future. The investigation of the mechanism for the defect-induced site preferences provides a reference for developing new photoluminescent materials.
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The uncontrollable formation of polymorphous Li deposits, e.g., whiskers, mosses, or dendrites resulting from nonuniform interfacial current distribution and internal stress release in the upward direction on the conventional current collector (e.g., Cu foil) of Li metal rechargeable batteries with a lithium-metal-free negatrode (LMFRBs), leads to rapid performance degradation or serious safety problems. The 3D carbon nanotubes (CNTs) skeleton has been proven to effectively reduce the current density and eliminate the internal accumulated stress. However, remarkable electrolyte decomposition, inherent Li source consumption due to repeated SEI formation, and Li+ intercalation in CNTs limit the application of 3D CNTs skeleton. Thus, it is necessary to avoid the side effects of the 3D CNTs skeleton and retain uniform interfacial current distribution and stress mitigation. In this work, we integrate the CNTs network with a soft functional polymer polyvinylidene fluoride (PVDF) to form a relatively dense coating layer on Cu foil, which can shield the contact between the internal surface of the 3D CNTs framework and the electrolyte. Simultaneously, the Li-F-rich SEI resulting from the partial reduction of PVDF with deposited Li and the soft nature of the coating layer release the accumulation of internal stress in the horizontal direction, resulting in mosses/whisker-free Li deposition. Thus, improved Li deposition/dissolution and stable cycling performance of the LMFRBs can be achieved.
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The present study aimed to examine the safety and healing effects of proton pump inhibitors (PPIs) in people with laryngopharyngeal reflux disease (LPRD). To find all relevant studies published before April 1, 2022, we searched the PubMed, Embase, Web of Science, Clinical Trials, Cochrane Library, CNKI, and Wanfang databases. For SLE, we looked for all randomized controlled clinical trials related to PPIs versus placebo-controlled treatment of LPRD. Overall efficiency, reflux symptom index (RSI), reflux finding score (RFS), improvement in cough and hoarseness, and adverse reactions were compared using the Review Manager 5.3. Using the reflux symptom index (RSI) as an outcome indicator for efficacy assessment, the PPI group showed significant improvement compared with the placebo group [MD = 3.35, 95% CI (1.34, 5.37, P < 0.05)]. In terms of overall efficacy, the PPI group showed effectiveness, but its efficacy was not statistically significantly dissimilar from that of the placebo group [OR = 1.62, 95% CI (0.89, 2.95), P > 0.05].
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Refluxo Laringofaríngeo , Inibidores da Bomba de Prótons , Humanos , Refluxo Laringofaríngeo/diagnóstico , Refluxo Laringofaríngeo/tratamento farmacológico , Faringe , Inibidores da Bomba de Prótons/efeitos adversos , Resultado do TratamentoRESUMO
In order to realize broad excitation and narrow emission red light phosphor, a new vanadium phosphate Ba2BiV2PO11 was selected as a host for Eu3+. Monitored at 619 nm, a wide band from 240 to 400 nm could be observed and inferred to be composed of Eu3+-O2- and V5+-O2- charge transfer bands, which could make it match well with the UV chip and the blue chip along with the characteristic excitation of Eu3+ at 465 nm. Under 354 nm excitation, the sample could emit high color purity red light, and the thermal quenching integral intensity showed good thermal stability. The generation of charge transfer bands was investigated in detail combined with the luminescence properties and the structure of the matrix. Moreover, the as-prepared phosphor could improve the white light performance of blue chip-activated YAG:Ce3+ and n-UV chip-activated tricolor phosphors. All the results indicated the multiple application potential of Ba2BiV2PO11:Eu3+ for white light-emitting diodes.
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Silicon monoxide (SiO) is considered as one of the most promising anode material candidates for next-generation high-energy-density lithium ion batteries (LIBs) due to its high specific capacity and relatively lower volume expansion than that of Si. However, a large number of irreversible products are formed during the first charging and discharging process, resulting in a low initial Coulombic efficiency (ICE) of SiO. Herein, we report an economical and convenient method to increase the ICE of SiO without sacrificing its specific capacity by a solid reaction between magnesium silicide (Mg2Si) and micron-sized SiO. The reaction product (named MSO) exhibits a unique core-shell structure with uniformly distributed Mg2SiO4 and Si as the shell and disproportionated SiO as the core. MSO exhibits a superior ICE and a high reversible capacity of 81.7% and 1306.1 mAh g-1, respectively, which can be further increased to 88.7% and 1446.4 mAh g-1 after carbon coating, and improved cyclic stability compared to bare SiO. This work provides a simple yet effective strategy to address the low ICE issue of SiO anode materials to promote the practical application of SiO.
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A novel apatite-based phosphor MgGd4Si3O13[Mg2Gd8(SiO4)6O2]:Ce3+, Mn2+ was designed and successfully synthesized by a solid-state reaction. Based on the different luminescence properties under 298 and 340 nm excitations, its potential application as a dual-excitation luminescent ratiometric thermometer was studied in detail. Under the excitations of 298 and 340 nm, the fluorescent intensity ratio of Ce3+ and Mn2+ is linearly correlated in the temperature range of 303-473 K. The sensitivity showed an opposite trend with the increase of temperature, and the maximum value was 0.95% K-1. These results indicated that MgGd4Si3O13: Ce3+, Mn2+ can be used as an ideal dual-excitation luminescent ratiometric thermometer.
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Background: Secretory otitis media is a very common nonsuppurative inflammatory disease in otorhinolaryngology. Ambroxol hydrochloride helps to improve ciliary movement in the ear canal and promote the dissolution and discharge of secretions. However, its effect still lacks systematic evaluation. We conducted a meta-analysis of clinical studies to systematically evaluate the application effect of ambroxol hydrochloride. Methods: A computer-based search of the Chinese Biomedical Database (CBM), China National Knowledge Infrastructure (CNKI), PubMed, and Web of Science databases was conducted using the keywords "Ambroxol hydrochloride" & "secretory otitis media". Randomized controlled trials published after 2015 were selected and then screened and analyzed using RevMan 5.4 software. Results: Ten studies involving a total of 998 patients were included. Meta-analysis showed that adding ambroxol hydrochloride to the original glucocorticoid treatment improved therapeutic efficacy [odds ratio (OR) =4.95, 95% confidence interval (CI): 3.27, 7.50, P<0.00001], reduced tympanic pressure after treatment [mean difference (MD) =-19.04, 95% CI: -22.72, -15.36, P<0.00001], and increased the pure tone threshold (MD =6.37, 95% CI: 5.36, 7.37, P<0.00001), without increasing adverse reactions (OR =0.51, 95% CI: 0.14, 1.85, P=0.30). Discussion: On the basis of the original treatment of secretory otitis media, adding ambroxol hydrochloride treatment improved the therapeutic effect, reduced tympanic pressure after treatment, and improved the pure tone threshold (hearing), without increasing adverse reactions.
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The continuous advancement of the Internet of Things (IoT) and photovoltaic technology has promoted the development of indoor photovoltaics (IPVs) that powers wireless devices. Nowadays, the CsPbX3 perovskite has received widespread attention because of its high power conversion efficiency (PCE) in an indoor environment and suitable band gap for IPVs. In this work, we regulated the thickness of the photoactive layer (to optimize the carrier transport process without affecting indoor absorption) and bromine substitution (to adjust the band gap and improve the quality of the film) to reduce trap-assisted carrier recombination. A CsPbI2.7Br0.3 perovskite cell with excellent performance was obtained, which is superior to c-Si cells in a low-light environment. The optimized device achieved PCE values of 32.69 and 33.11% under a 1000 lux fluorescent lamp and white light-emitting diode (WLED) illumination. The J-V hysteresis of the device is also effectively suppressed. Moreover, it has a steady-state output power of 7.76 µW (0.09 cm2, and can be enhanced by enlarging the areas), which can meet the consumption of many small wireless devices. It is worth noting that the optimized device has excellent applicability to be used in a complex indoor environment.
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Fibre batteries are of significant interest because they can be woven into flexible textiles to form compact, wearable and light-weight power solutions1,2. However, current methods adapted from planar batteries through layer-by-layer coating processes can only make fibre batteries with low production rates, which fail to meet the requirements for real applications2. Here, we present a new and general solution-extrusion method that can produce continuous fibre batteries in a single step at industrial scale. Our three-channel industrial spinneret simultaneously extrudes and combines electrodes and electrolyte of fibre battery at high production rates. The laminar flow between functional components guarantees their seamless interfaces during extrusion. Our method yields 1,500 km of continuous fibre batteries for every spinneret unit, that is, more than three orders of magnitude longer fibres than previously reported1,2. Finally, we show a proof-of-principle for roughly 10 m2 of woven textile for smart tent applications, with a battery with energy density of 550 mWh m-2.