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Photodetectors are in huge demand in multiple fields, such as remote sensing, chemical detection, security, and medical imaging. Carbon nanotubes (CNTs) are promising candidates for high-performance photodetectors due to their extraordinary optical and electrical properties. However, the performance of previously reported CNT-based photodetectors is far from the intrinsic photoelectrical properties of CNTs because of the noncontinuous lengths, structural defects, and unsatisfactory structural design of the previously used short CNTs. The key to improving the performance of CNT-based photodetectors is to increase the length and structural quality of the CNTs. Herein, high-performance photodetectors were fabricated by using high-density suspended ultralong CNTs (SUCNTs). The suspended structures of ultralong CNTs not only reduced the electron-phonon interactions generated by substrates but also largely avoided bolometric effects through efficient heat dissipation. Moreover, the characteristics of high areal density and defect-free structures of SUCNTs could increase the effective absorption areas and improve their carrier mobility, resulting in enhanced photoconductive responses. Consequently, compared with the nonsuspended short CNTs, the SUCNT-based photodetectors achieved significantly improved photodetection performance, such as high responsivity (0.181 A W-1), detectivity (1.20 × 109 cm Hz1/2 W-1), ultrafast response (0.13 ms), and broad detection range (405-850 nm).
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BACKGROUND: Postoperative infection of breast implants can lead to implant removal and other complications. This study aimed to investigate the presence of costal cartilage infection following breast implant surgery and the diagnostic role of PET/CT in identifying this rare complication. PATIENTS AND METHODS: A retrospective study included 16 patients with persistent infections after breast implant removal surgery. Patients underwent PET/CT scans before surgery, and surgical plans were made based on PET/CT findings. Surgical procedures were guided by PET/CT, and specimens were collected for pathological examination and microbiological culture. Follow-up assessments were performed at 1, 3, and 12 months postoperatively. RESULTS: Among the 16 patients, 11 were diagnosed with costal cartilage infection, whereas 5 had subcutaneous soft tissue infections. PET/CT accurately identified costal cartilage infection in all cases and localized the infected costal cartilage in the majority of cases. Microbiological culture results showed various pathogens. All patients were cured with one or staged surgery. CONCLUSION: Costal cartilage infection following breast implant surgery is a significant concern. PET/CT plays a crucial role in the accurate diagnosis and localization of infected costal cartilage, aiding in appropriate surgical management. Patients should be closely monitored for the possibility of costal cartilage infection when experiencing persistent symptoms after breast implant surgery.
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Implantación de Mama , Implantes de Mama , Cartílago Costal , Tomografía Computarizada por Tomografía de Emisión de Positrones , Humanos , Femenino , Estudios Retrospectivos , Persona de Mediana Edad , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Adulto , Implantes de Mama/efectos adversos , Cartílago Costal/trasplante , Implantación de Mama/efectos adversos , Infecciones Relacionadas con Prótesis/diagnóstico , Infecciones Relacionadas con Prótesis/diagnóstico por imagen , Infecciones Relacionadas con Prótesis/etiología , Infección de la Herida Quirúrgica/diagnóstico , Infección de la Herida Quirúrgica/etiología , Infección de la Herida Quirúrgica/microbiología , Remoción de Dispositivos , AncianoRESUMEN
BACKGROUND: Axillary hyperhidrosis and bromhidrosis are common clinical diseases, affecting the patients' work and life. Negative-pressure suction-curettage is the most popular treatment now, but challenged by a new microwave-based therapy (MiraDry). We intend to compare the safety and efficiency of the 2 treatments. METHODS: A retrospective analysis of 39 female patients with both primary hyperhidrosis and bromhidrosis was conducted. Seventeen patients were treated with MiraDry, and 22 underwent negative-pressure suction-curettage. The postoperative follow-up program included sweat and odor assessments, satisfaction measurement, safety evaluation, and recurrence assessment at different time points until 12 months. RESULTS: Both treatments showed a significant reduction (P < 0.05) in HDSS score and odor level at 6 and 12 months compared with the baseline. No significant difference in relative reduction was observed between the 2 groups. The satisfaction score of the microwave-based therapy group was higher than that of the negative-pressure suction-curettage group, but no statistical difference was found. The difference in the recurrence rate and complication rate between the groups did not reach significance. CONCLUSIONS: Microwave-based therapy is a noninvasive treatment with durable effects, low risks, shorter downtime, good appearance, and high satisfaction for axillary hyperhidrosis and bromhidrosis.
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Axila , Hiperhidrosis , Microondas , Legrado por Aspiración , Humanos , Hiperhidrosis/cirugía , Hiperhidrosis/terapia , Femenino , Estudios Retrospectivos , Microondas/uso terapéutico , Adulto , Legrado por Aspiración/métodos , Resultado del Tratamiento , Satisfacción del Paciente , Adulto Joven , Estudios de Seguimiento , Persona de Mediana EdadRESUMEN
Ultralong carbon nanotubes (CNTs) are considered as promising candidates for many cutting-edge applications. However, restricted by the extremely low yields of ultralong CNTs, their practical applications can hardly be realized. Therefore, new methodologies shall be developed to boost the growth efficiency of ultralong CNTs and alleviate their areal density decay at the macroscale level. Herein, a facile, universal, and controllable method for the in situ synthesis of floating bimetallic catalysts (FBCs) is proposed to grow ultralong CNT arrays with high yields and uniformity. Ferrocene and metal acetylacetonates serve as catalyst precursors, affording the successful synthesis of a series of FBCs with controllable compositions. Among these FBCs, the optimized FeCu catalyst increases the areal density of ultralong CNT arrays to a record-breaking value of ≈8100 CNTs mm-1 and exhibits a lifetime 3.40 times longer than that of Fe, thus achieving both high yields and uniformity. A 30-centimeters-long and high-density ultralong CNT array is also successfully grown with the assistance of FeCu catalysts. As evidenced by this kinetic model and molecular dynamics simulations, the introduction of Cu into Fe can simultaneously improve the catalyst fluidity and decrease carbon solubility, and an optimal catalytic performance will be achieved by balancing this tradeoff.
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Airflow sensors are in huge demand in many fields such as the aerospace industry, weather forecasting, environmental monitoring, chemical and biological engineering, health monitoring, wearable smart devices, etc. However, traditional airflow sensors can hardly meet the requirements of these applications in the aspects of sensitivity, response speed, detection threshold, detection range, and power consumption. Herein, this work reports high-performance airflow sensors based on suspended ultralong carbon nanotube (CNT) crossed networks (SCNT-CNs). The unique topologies of SCNT-CNs with abundant X junctions can fully exhibit the extraordinary intrinsic properties of ultralong CNTs and significantly improve the sensing performance and robustness of SCNT-CNs-based airflow sensors, which simultaneously achieved high sensitivity, fast response speed, low detection threshold, and wide detection range. Moreover, the capability for encapsulation also guaranteed the practicality of SCNT-CNs, enabling their applications in respiratory monitoring, flow rate display and transient response analysis. Simulations were used to unveil the sensing mechanisms of SCNT-CNs, showing that the piezoresistive responses were mainly attributed to the variation of junction resistances. This work shows that SCNT-CNs have many superiorities in the fabrication of advanced airflow sensors as well as other related applications.
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Radiative cooling is a zero-energy technology that enables subambient cooling by emitting heat into outer space (~3 K) through the atmospheric transparent windows. However, existing designs typically focus only on the main atmospheric transparent window (8-13 µm) and ignore another window (16-25 µm), under-exploiting their cooling potential. Here, we show a dual-selective radiative cooling design based on a scalable thermal emitter, which exhibits selective emission in both atmospheric transparent windows and reflection in the remaining mid-infrared and solar wavebands. As a result, the dual-selective thermal emitter exhibits an ultrahigh subambient cooling capacity (~9 °C) under strong sunlight, surpassing existing typical thermal emitters (≥3 °C cooler) and commercial counterparts (as building materials). Furthermore, the dual-selective sample also exhibits high weather resistance and color compatibility, indicating a high practicality. This work provides a scalable and practical radiative cooling design for sustainable thermal management.
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In water purification, the performance of heterogeneous advanced oxidation processes significantly relies upon the utilization of the catalyst's specific surface area (SSA). However, the presence of the structural "dead volume" and pore-size-induced diffusion-reaction trade-off limitation restricts the functioning of the SSA. Here, we reported an effective approach to make the best SSA by changing the traditional 3D spherule catalyst into a 2D-like form and creating an in situ micro-nanolinked structure. Thus, a 2D-like catalyst was obtained which was characterized by a mini "paddy field" surface, and it exhibited a sharply decreased dead volume, a highly available SSA and oriented flexibility. Given its paddy-field-like mass-transfer routine, the organic capture capability was 7.5-fold higher than that of the catalyst with mesopores only. Moreover, such a catalyst exhibited a record-high O3-to-·OH transition rate of 2.86 × 10-8 compared with reported millimetric catalysts (metal base), which contributed to a 6.12-fold higher total organic removal per catalyst mass than traditional 3D catalysts. The facile scale preparation, performance stability, and significant material savings with the 2D-like catalyst were also beneficial for practical applications. Our findings provide a unique and general approach for designing potential catalysts with excellent performance in water purification.
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Ozono , Contaminantes Químicos del Agua , Purificación del Agua , Oxidación-Reducción , Metales , Catálisis , Contaminantes Químicos del Agua/análisisRESUMEN
The coloration of carbon nanotube (CNT) fibers (CNTFs) is a long-lasting challenge because of the intrinsic black color and chemically inert surfaces of CNTs, which cannot satisfy the aesthetic and fashion requirements and thus significantly restrict their performance in many cutting-edge fields. Recently, a structural coloration method of CNTFs was developed by our group using atomic layer deposition (ALD) technology. However, the ALD-based structural coloration method of CNTFs is expensive, time-consuming, and not suitable for the large-scale production of colorful CNTFs. Herein, we developed a very simple and scalable liquid-phase method to realize the structural coloration of CNTFs. A SiO2/ethanol dispersion containing SiO2 nanospheres with controllable sizes was synthesized. The SiO2 nanospheres could self-assemble into photonic crystal layers on the surface of CNTFs and exhibited brilliant colors. The colors of SiO2 nanoparticle-coated CNTFs could be easily changed by tuning the sizes of SiO2 nanospheres. This method provides a simple, effective, and promising way for the large-scale production of colorful CNTFs.
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Ultralong carbon nanotubes (CNTs) are in huge demand in many cutting-edge fields due to their macroscale lengths, perfect structures, and extraordinary properties, while their practical application is limited by the difficulties in their mass production. Herein, we report the synthesis of ultralong CNTs with a dramatically increased yield by a simple but efficient substrate interception and direction strategy (SIDS), which couples the advantages of floating-catalyst chemical vapor deposition with the flying-kite-like growth mechanism of ultralong CNTs. The SIDS-assisted approach prominently improves the catalyst utilization and significantly increases the yield. The areal density of the ultralong CNT arrays with length of over 1 cm reached a record-breaking value of â¼6700 CNTs mm-1, which is 2-3 orders of magnitude higher than the previously reported values obtained by traditional methods. The SIDS provides a solution for synthesizing high-quality ultralong CNTs with high yields, laying the foundation for their mass production.
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Carbon nanotubes (CNTs) are promising candidates for numerous cutting-edge fields because of their excellent properties. However, the inherent black color of CNTs cannot satisfy the aesthetic/fashion requirement, and the flammability of CNTs severely restricts their application in high-temperature environments with oxygen. Here, we realized a structural coloration of CNTs by coating them with amorphous TiO2 layers. By tuning the TiO2 coating thickness, both CNT fibers and membranes exhibited controllable and brilliant colors, which exhibited remarkable superdurability that could endure 2000 cycles of laundering tests and more than 10 months of high-intensity ultraviolet irradiation. The TiO2-coated CNTs exhibited a notable fire-retardant performance and could endure 8 hours of fire burning. The structural coloration of CNTs with excellent fire retardance substantially improves their performance and broadens their applications.
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Dwarfed stature is a desired trait for modern orchard production systems. One effective strategy for dwarfing cultivation is exogenously applying plant growth retardants (PGRs) to plants. However, for many economic fruit trees, the current knowledge on the regulatory mechanisms underlying the dwarfing effect of PGRs is limited, which largely restricts the agricultural application of PGRs. In this study, we exogenously applied three kinds of PGRs [paclobutrazol, daminozide (B9), and mannitol] to the seedlings of pomegranate (Punica granatum L.) and performed comparative transcriptome analysis to elucidate the molecular features of PGR-induced dwarfing in pomegranates. Our results showed that all the three PGRs could significantly suppress plant growth of pomegranate. The inhibition of auxin biosynthetic processes, as well as auxin-mediated shoot development, may be considered as the main reason for the dwarfing. Besides that, different PGRs were also found to induce dwarfing via specific mechanisms, for example, cellular response to strigolactone was particularly suppressed by the application of paclobutrazol, while the level of carbohydrate homeostasis and metabolism were downregulated in conditions of either B9 or mannitol treatments. Furthermore, exogenous PGR application was supposed to cause adverse impacts on the normal physiological process of pomegranate seedlings, which may bring extra burden to pomegranate plants. These novel findings unveiled the genetic basis underlying the dwarfing in pomegranates, which provides deeper insights into PGR-mediated dwarfing cultivation of pomegranates.
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Genomic studies are now poised to explore whole communities of species. The ~70 species of woody plants that anchor the coastal ecosystems of the tropics, collectively referred to as mangroves, are particularly suited to this exploration. In this study, we de novo sequenced the whole genomes of 32 mangroves, which we combined with other sequences of 30 additional species, comprising almost all mangroves globally. These community-wide genomic data will be valuable for ecology, evolution and biodiversity research. While the data revealed 27 independent origins of mangroves, the total phylogeny shows only modest increases in species number, even in coastal areas of active speciation, suggesting that mangrove extinction is common. A possible explanation for common extinction is the frequent sea-level rises and falls (SLRs and SLFs) documented in the geological record. Indeed, near-extinctions of species with extremely small population size (N) often happened during periods of rapid SLR, as revealed by the genome-wide heterozygosity of almost all mangroves. Reduction in N has possibly been further compounded by population fragmentation and the subsequent accumulation of deleterious mutations, thus pushing mangroves even closer to extinction. Crucially, the impact of the next SLR will be exacerbated by human encroachment into these mangrove habitats, potentially altering the ecosystems of tropical coasts irreversibly.
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Ecosistema , Bosques , Genoma , Humanos , Filogenia , PlantasRESUMEN
Transition metal oxides (TMOs) are promising inorganic electrochromic materials (ECMs) that can be widely used in electronic displays and adaptive camouflage. However, there are still huge challenges for TMOs to simultaneously achieve multicolor transformation capability and good cycling stability. Herein, we assemble Au-modified (0.01 wt %) VxO2x+1 (x > 2) nanoflowers (Au@VxO2x+1 NFs) composed of two-dimensional porous nanosheets containing two valences states of vanadium (V4+ and V5+). The Au@VxO2x+1 NFs exhibits outstanding electrochromic performance with five reversible color transformations (orange, yellow, green, gray, and blue) at a voltage less than 1.5 V and excellent cycling stability (2000 cycles without significant decay). To the best of our knowledge, this is the first time that a single vanadium oxide ECM, rather than a device, realizes five color changes. This work provides a feasible way for the efficient preparation of multicolor electrochromic TMOs. The newly developed Au@VxO2x+1 NFs demonstrate the potential application in adaptive camouflage.
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Single-atom catalysts with high activity and efficient atom utilization have great potential in the electrocatalysis field, especially for rechargeable zinc-air batteries (ZABs). However, it is still a serious challenge to rationally construct a single-atom catalyst with satisfactory electrocatalytic activity and long-term stability. Here, we simultaneously realize the atomic-level dispersion of cobalt and the construction of carbon nanotube (CNT)-linked N-doped porous carbon nanofibers (NCFs) via an electrospinning strategy. In this hierarchical structure, the Co-N4 sites provide efficient oxygen reduction/evolution electrocatalytic activity, the porous architectures of NCFs guarantee the active site's accessibility, and the interior CNTs enhance the flexibility and mechanical strength of porous fibers. As a binder-free air cathode, the as-prepared catalysts deliver superdurability of 600 h at 10 mA cm-2 for aqueous ZABs and considerable flexibility and a small voltage gap for all-solid-state ZABs. This work provides an effective single-atom design/nanoengineering for superdurable zinc-air batteries.
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High-performance airflow sensors are in great demand in numerous fields but still face many challenges, such as slow response speed, low sensitivity, large detection threshold, and narrow sensing range. Carbon nanotubes (CNTs) exhibit many advantages in fabricating airflow sensors due to their nanoscale diameters, excellent mechanical and electrical properties, and so on. However, the intrinsic extraordinary properties of CNTs are not fully exhibited in previously reported CNT-based airflow sensors due to the mixed structures of macroscale CNT assemblies. Herein, this article presents suspended CNT networks (SCNTNs) as high-performance airflow sensors, which are self-assembled by ultralong CNTs and short CNTs in a one-step floating catalyst chemical vapor deposition process. The SCNTN-based airflow sensors achieved a record-breaking short response time of 0.021 s, a high sensitivity of 0.0124 s m-1 , a small detection threshold of 0.11 m s-1 , and a wide detection range of ≈0.11-5.51 m s-1 , superior to most of the state-of-the-art airflow sensors. To reveal the sensing mechanism, an acoustic response testing system and a mathematical model are developed. It is found that the airflow-caused intertube stress change resulted in the resistance variation of SCNTNs.
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The development of high-efficiency and durable bifunctional electrocatalysts for both the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is critical for the widespread application of rechargeable zinc-air (Zn-air) batteries. This calls for rational screening of targeted ORR/OER components and precise control of their atomic and electronic structures to produce synergistic effects. Here, we report a Mn-doped RuO2 (Mn-RuO2) bimetallic oxide with atomic-scale dispersion of Mn atoms into the RuO2 lattice, which exhibits remarkable activity and super durability for both the ORR and OER, with a very low potential difference (ΔE) of 0.64 V between the half-wave potential of ORR (E1/2) and the OER potential at 10 mA cm-2 (Ej10) and a negligible decay of E1/2 and Ej10 after 250â¯000 and 30â¯000 CV cycles for ORR and OER, respectively. Moreover, Zn-air batteries using the Mn-RuO2 catalysts exhibit a high power density of 181 mW cm-2, low charge/discharge voltage gaps of 0.69/0.96/1.38 V, and ultralong lifespans of 15â¯000/2800/1800 cycles (corresponding to 2500/467/300 h operation time) at a current density of 10/50/100 mA cm-2, respectively. Theoretical calculations reveal that the excellent performances of Mn-RuO2 is mainly due to the precise optimization of valence state and d-band center for appropriate adsorption energy of the oxygenated intermediates.
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The fast visualization and manipulation of individual carbon nanotubes (CNTs) has always been a significant technology for their fundamental research. Here, a fast and facile approach is proposed to realize the optical observation of individual suspended CNTs and CNT networks under conventional optical microscopes with the assistance of tar nanodroplets from smoke. The nanodroplets deposited on CNTs render them with strong light scattering to visible light, thus making the CNTs visible under optical microscopes. This visualization method is controllable, environmentally friendly, low-cost, and can be completed in just a few seconds in ambient conditions. Besides, the tar nanodroplets can be easily removed from the CNTs by laser irradiation. More importantly, the smoke sources are widely available and there are no strict requirements for operating conditions. This smoke-assisted visualization method shows great potential in the fundamental research of CNTs.
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Historic climate changes drive geographical populations of coastal plants to contract and recover dynamically, even die out completely. Species suffering from such bottlenecks usually lose intraspecific genetic diversity, but how do these events influence population subdivision patterns of coastal plants? Here, we investigated this question in the typical coastal plant: mangrove species Aegiceras corniculatum. Inhabiting the intertidal zone of the tropical and subtropical coast of the Indo-West Pacific oceans, its populations are deemed to be greatly shaped by historic sea-level fluctuations. Using dual methods of Sanger and Illumina sequencing, we found that the 18 sampled populations were structured into two groups, namely, the "Indo-Malayan" group, comprising three subgroups (the northern South China Sea, Gulf of Bengal, and Bali), and the "Pan-Australasia" group, comprising the subgroups of the southern South China Sea and Australasia. Based on the approximate Bayesian computations and Stairway Plot, we inferred that the southern South China Sea subgroup, which penetrates the interior of the "Indo-Malayan" group, originated from the Australasia subgroup, accompanied by a severe bottleneck event, with a spot of gene flow from both the Australasia and "Indo-Malayan" groups. Geographical barriers such as the Sundaland underlie the genetic break between Indian and Pacific Oceans, but the discontinuity between southern and northern South China Sea was originated from genetic drift in the bottleneck event. Hence, we revealed a case evidencing that the bottleneck event promoted population subdivision. This conclusion may be applicable in other taxa beyond coastal plants.
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Flujo Génico , Primulaceae , Teorema de Bayes , Evolución Biológica , Océano Pacífico , Filogenia , Primulaceae/genéticaRESUMEN
Structural colors, generated by the interaction of interference, diffraction, and scattering between incident light and periodic nanostructured surfaces with features of the same scale with incident visible light wavelengths, have recently attracted intense interest in a wide range of research fields, due to their advantages such as various brilliant colors, long-term stability and environmental friendliness, low energy consumption, and mysterious biological functions. Tremendous effort has been made to design structural colors and considerable progress has been achieved in the past few decades. However, there are still significant challenges and obstacles, such as durability, portability, compatibility, recyclability, mass production of structural-color materials, etc., that need to be solved by rational structural design and novel manufacturing strategies. In this review, we summarize the recent progress of bio-inspired structural colors and their applications. First, we introduce several typical natural structural colors displayed by living organisms from fundamental optical phenomena, including interference, diffraction grating, scattering, photonic crystals effects, the combination of different phenomena, etc. Subsequently, we review recent progress in bio-inspired artificial structural colors generated from advanced micro/nanoscale manufacturing strategies to relevant biomimetic approaches, including self-assembly, template methods, phase conversion, magnetron sputtering, atomic layer deposition, etc. Besides, we also present the current and potential applications of structural colors in various fields, such as displays, anti-counterfeiting, wearable electronics, stealth, printing, etc. Finally, we discuss the challenges and future development directions of structural colors, aiming to push forward the research and applications of structural-color materials.