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Because of their large surface areas, nanotubes and nanowires demonstrate exquisite mechanical coupling to their surroundings, promising advanced sensors and nanomechanical devices. However, this environmental sensitivity has resulted in several ambiguous observations of vibrational coupling across various experiments. Herein, we demonstrate a temperature-dependent Radial Breathing Mode (RBM) frequency in free-standing, electron-diffraction-assigned Double-Walled Carbon Nanotubes (DWNTs) that shows an unexpected and thermally reversible frequency downshift of 10 to 15%, for systems isolated in vacuum. An analysis based on a harmonic oscillator model assigns the distinctive frequency cusp, produced over 93 scans of 3 distinct DWNTs, along with the hyperbolic trajectory, to a reversible increase in damping from graphitic ribbons on the exterior surface. Strain-dependent coupling from self-tensioned, suspended DWNTs maintains the ratio of spring-to-damping frequencies, producing a stable saturation of RBM in the low-tension limit. In contrast, when the interior of DWNTs is subjected to a water-filling process, the RBM thermal trajectory is altered to that of a Langmuir isobar and elliptical trajectories, allowing measurement of the enthalpy of confined fluid phase change. These mechanisms and quantitative theory provide new insights into the environmental coupling of nanomechanical systems and the implications for devices and nanofluidic conduits.
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Chemoselective modification of specific residues within a given protein poses a significant challenge, as the microenvironment of amino acid residues in proteins is variable. Developing a universal molecular platform with tunable chemical warheads can provide powerful tools for precisely labeling specific amino acids in proteins. Cysteine and lysine are hot targets for chemoselective modification, but current cysteine/lysine-selective warheads face challenges due to cross-reactivity and unstable reaction products. In this study, a versatile fluorescent platform is developed for highly selective modification of cysteine/lysine under biocompatible conditions. Chloro- or phenoxy-substituted NBSe derivatives effectively labeled cysteine residues in the cellular proteome with high specificity. This finding also led to the development of phenoxy-NBSe phototheragnostic for the diagnosis and activatable photodynamic therapy of GSH-overexpressed cancer cells. Conversely, alkoxy-NBSe derivatives are engineered to selectively react with lysine residues in the cellular environment, exhibiting excellent anti-interfering ability against thiols. Leveraging a proximity-driven approach, alkoxy-NBSe probes are successfully designed to demonstrate their utility in bioimaging of lysine deacetylase activity. This study also achieves integrating a small photosensitizer into lysine residues of proteins in a regioselective manner, achieving photoablation of cancer cells activated by overexpressed proteins.
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Cisteína , Colorantes Fluorescentes , Lisina , Lisina/química , Cisteína/química , Cisteína/metabolismo , Humanos , Colorantes Fluorescentes/química , Fotoquimioterapia/métodos , Línea Celular TumoralRESUMEN
Objective: To investigate the effectiveness of double EndoButton suture fixation Latarjet procedure in the treatment of shoulder anterior dislocation with glenoid bone defect caused by military training injuries. Methods: The clinical data of 14 patients with anterior shoulder dislocation with glenoid bone defect due to military training injuries who met the selection criteria and admitted between August 2021 and December 2022 were retrospectively analyzed. All patients were male, the age ranged from 21 to 38 years, with an average of 26.8 years. The time from initial dislocation to operation was 6-15 months, with an average of 10.2 months. Anterior shoulder dislocation occurred 5-12 times, with an average of 8.2 times. All glenoid bone defects were more than 10%, including 5 cases of 10%-15%, 8 cases of 15%-20%, and 1 case of 24%. All patients were treated by double EndoButton suture fixation Latarjet procedure. The operation time and complications were recorded. The shoulder function and pain were evaluated by the American Association for Shoulder and Elbow Surgery (ASES) score, Rowe score, Instability Severity Index Score (ISIS), and visual analogue scale (VAS) score before and after operation. The range of motion of the shoulder was recorded, including forward flexion, 0° external rotation, and abduction 90° external rotation. The position, healing, and resorption of the bone mass were evaluated by three-dimensional CT of shoulder joint after operation. Results: All patients successfully completed the operation, and the operation time was 100-150 minutes, with an average of 119.7 minutes. There was no complications such as infection, vascular and nerve injury. All patients were followed up 12-20 months, with an average of 15.6 months. During the follow-up, 4 patients had bone mass separation, absorption, and recurrent anterior dislocation, and the shoulder joint fear test was positive. Imaging of the remaining patients showed that the bone mass healed well, no anterior dislocation recurrence occurred, and the healing time was 3-7 months (mean, 4.7 months). At last follow-up, the range of motion, ASES score, Rowe score, ISIS score, and VAS score of the patients significantly improved when compared with those before operation ( P<0.05). Conclusion: The effectiveness of double EndoButton suture fixation Latarjet procedure for the treatment of anterior shoulder dislocation with glenoid bone defect caused by military training injury is satisfactory.
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Personal Militar , Rango del Movimiento Articular , Luxación del Hombro , Articulación del Hombro , Técnicas de Sutura , Humanos , Luxación del Hombro/cirugía , Adulto , Masculino , Estudios Retrospectivos , Adulto Joven , Articulación del Hombro/cirugía , Resultado del Tratamiento , Escápula/cirugía , Escápula/lesionesRESUMEN
Progressive neuronal dysfunction and death are key features of neurodegenerative diseases; therefore, promoting neurogenesis in neurodegenerative diseases is crucial. With advancements in proteomics and high-throughput sequencing technology, it has been demonstrated that histone post-transcriptional modifications (PTMs) are often altered during neurogenesis when the brain is affected by disease or external stimuli and that the degree of histone modification is closely associated with the development of neurodegenerative diseases. This review aimed to show the regulatory role of histone modifications in neurogenesis and neurodegenerative diseases by discussing the changing patterns and functional significance of histone modifications, including histone methylation, acetylation, ubiquitination, phosphorylation, and lactylation. Finally, we explored the control of neurogenesis and the development of neurodegenerative diseases by artificially modulating histone modifications.
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Histonas , Enfermedades Neurodegenerativas , Neurogénesis , Procesamiento Proteico-Postraduccional , Neurogénesis/fisiología , Enfermedades Neurodegenerativas/metabolismo , Enfermedades Neurodegenerativas/genética , Humanos , Histonas/metabolismo , Animales , Código de HistonasRESUMEN
Central nervous system (CNS) damage is usually irreversible owing to the limited regenerative capability of neurons. Following CNS injury, astrocytes are reactively activated and are the key cells involved in post-injury repair mechanisms. Consequently, research on the reprogramming of reactive astrocytes into neurons could provide new directions for the restoration of neural function after CNS injury and in the promotion of recovery in various neurodegenerative diseases. This review aims to provide an overview of the means through which reactive astrocytes around lesions can be reprogrammed into neurons, to elucidate the intrinsic connection between the two cell types from a neurogenesis perspective, and to summarize what is known about the neurotranscription factors, small-molecule compounds and MicroRNA that play major roles in astrocyte reprogramming. As the malignant proliferation of astrocytes promotes the development of glioblastoma multiforme (GBM), this review also examines the research advances on and the theoretical basis for the reprogramming of GBM cells into neurons and discusses the advantages of such approaches over traditional treatment modalities. This comprehensive review provides new insights into the field of GBM therapy and theoretical insights into the mechanisms of neurological recovery following neurological injury and in GBM treatment.
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Astrocitos , Neoplasias Encefálicas , Reprogramación Celular , Glioblastoma , Neuronas , Humanos , Astrocitos/metabolismo , Astrocitos/patología , Glioblastoma/patología , Neuronas/metabolismo , Neuronas/patología , Animales , Neoplasias Encefálicas/patología , Neurogénesis , Sistema Nervioso Central/patologíaRESUMEN
Understanding the relationship between plant diversity and invasibility is essential in invasion ecology. Species-rich communities are hypothesized to be more resistant to invasions than species-poor communities. However, while soil microorganisms play a crucial role in regulating this diversity-invasibility relationship, the effects of plant competition mode and soil nutrient status on their role remain unclear. To address this, we conducted a two-stage greenhouse experiment. Soils were first conditioned by growing nine native species separately in them for 1 year, then mixed in various configurations with soils conditioned using one, three, or six species, respectively. Next, we inoculated the mixed soil into sterilized substrate soil and planted the alien species Rhus typhina and native species Ailanthus altissima as test plants. We set up two competition modes (intraspecific and interspecific) and two nutrient levels (fertilization using slow-release fertilizer and nonfertilization). Under intraspecific competition, regardless of fertilization, the biomass of the alien species was higher in soil conditioned by six native species. By contrast, under interspecific competition, the biomass increased without fertilization but remained stable with fertilization in soil conditioned by six native species. Analysis of soil microbes suggests that pathogens and symbiotic fungi in diverse plant communities influenced R. typhina growth, which varied with competition mode and nutrient status. Our findings suggest that the soil microbiome is pivotal in mediating the diversity-invasibility relationship, and this influence varies according to competition mode and nutrient status.
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Group 1 elements exhibit the lowest electronegativity values in the Periodic Table. The chemical reduction of Group 1 metal cations M+ to M(0) is extremely challenging. Common tetraaryl borates demonstrate limited redox properties and are prone to decomposition upon oxidation. In this study, by employing simple yet versatile bipyridines as ligands, we synthesized a series of redox-active borate anions characterized by NMR and X-ray single-crystal diffraction. Notably, the borate anion can realize the reduction of Li+, generating elemental lithium metal and boron radical, thereby demonstrating its potent reducing ability. Furthermore, it can serve as a powerful two-electron-reducing reagent and be readily applied in various reductive homo-coupling reactions and Birch reduction of acridine. Additionally, this borate anion demonstrates its catalytic ability in the selective two-electron reduction of CO2 into CO.
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Electron-precise B-B bonded compounds are valuable reagents in organic syntheses, which can be used as key starting material for the synthesis of functionalized organoboranes. Bis(pinacolato)diborane(4) B2 pin2 and its derivatives are among the most studied diboron species. However, their B-B bonds usually need to be activated by transition metal catalysts or bases for further transformations. Recently, many well-designed/reactive electron-precise B-B bonded compounds have been developed, which could facilitate direct reactions with small molecules, unsaturated substrates, and electrophiles. This review highlights the synthesis, structure, and reactivity of neutral and anionic B-B bonded compounds.
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Four-dimensional scanning transmission electron microscopy (4D-STEM) has recently gained widespread attention for its ability to image atomic electric fields with sub-Ångstrom spatial resolution. These electric field maps represent the integrated effect of the nucleus, core electrons and valence electrons, and separating their contributions is non-trivial. In this paper, we utilized simultaneously acquired 4D-STEM center of mass (CoM) images and annular dark field (ADF) images to determine the projected electron charge density in monolayer MoS2. We evaluate the contributions of both the core electrons and the valence electrons to the derived electron charge density; however, due to blurring by the probe shape, the valence electron contribution forms a nearly featureless background while most of the spatial modulation comes from the core electrons. Our findings highlight the importance of probe shape in interpreting charge densities derived from 4D-STEM and the need for smaller electron probes.
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Confined fluids and electrolyte solutions in nanopores exhibit rich and surprising physics and chemistry that impact the mass transport and energy efficiency in many important natural systems and industrial applications. Existing theories often fail to predict the exotic effects observed in the narrowest of such pores, called single-digit nanopores (SDNs), which have diameters or conduit widths of less than 10 nm, and have only recently become accessible for experimental measurements. What SDNs reveal has been surprising, including a rapidly increasing number of examples such as extraordinarily fast water transport, distorted fluid-phase boundaries, strong ion-correlation and quantum effects, and dielectric anomalies that are not observed in larger pores. Exploiting these effects presents myriad opportunities in both basic and applied research that stand to impact a host of new technologies at the water-energy nexus, from new membranes for precise separations and water purification to new gas permeable materials for water electrolyzers and energy-storage devices. SDNs also present unique opportunities to achieve ultrasensitive and selective chemical sensing at the single-ion and single-molecule limit. In this review article, we summarize the progress on nanofluidics of SDNs, with a focus on the confinement effects that arise in these extremely narrow nanopores. The recent development of precision model systems, transformative experimental tools, and multiscale theories that have played enabling roles in advancing this frontier are reviewed. We also identify new knowledge gaps in our understanding of nanofluidic transport and provide an outlook for the future challenges and opportunities at this rapidly advancing frontier.
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A sulfur dioxide (SO2) gas sensor based on the photoacoustic spectroscopy technology in a sulfur hexafluoride (SF6) gas matrix was demonstrated for SF6 decomposition components monitoring in the power system. A passive Q-switching laser diode (LD) pumped all-solid-state 266â nm deep-ultraviolet laser was exploited as the laser excitation source. The photoacoustic signal amplitude is linear related to the incident optical power, whereas, a random laser power jitter is inevitable since the immature laser manufacturing technology in UV spectral region. A compact laser power stabilization system was developed for better sensor performance by adopting a photodetector, a custom-made internal closed-loop feedback controller and a Bragg acousto-optic modulator (AOM). The out-power stability of 0.04% was achieved even though the original power stability was 0.41% for â¼ 2 hours. A differential two-resonator photoacoustic cell (PAC) was designed for weak photoacoustic signal detection. The special physical constants of SF6 buffer gas induced a high-Q factor of 85. A detection limit of 140 ppbv was obtained after the optimization, which corresponds to a normalized noise equivalent absorption coefficient of 3.2 × 10-9â cm-1WHz-1/2.
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Memory CD8+T cells participate in the fight against infection and tumorigenesis as well as in autoimmune disease progression because of their efficient and rapid immune response, long-term survival, and continuous differentiation. At each stage of their formation, maintenance, and function, the cell metabolism must be adjusted to match the functional requirements of the specific stage. Notably, enhanced glycolytic metabolism can generate sufficient levels of adenosine triphosphate (ATP) to form memory CD8+T cells, countering the view that glycolysis prevents the formation of memory CD8+T cells. This review focuses on how glycometabolism regulates memory CD8+T cells and highlights the key mechanisms through which the mammalian target of rapamycin (mTOR) signaling pathway affects memory CD8+T cell formation, maintenance, and function by regulating glycometabolism. In addition, different subpopulations of memory CD8+T cells exhibit different metabolic flexibility during their formation, survival, and functional stages, during which the energy metabolism may be critical. These findings which may explain why enhanced glycolytic metabolism can give rise to memory CD8+T cells. Modulating the metabolism of memory CD8+T cells to influence specific cell fates may be useful for disease treatment.
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Memoria Inmunológica , Serina-Treonina Quinasas TOR , Adenosina Trifosfato/metabolismo , Animales , Linfocitos T CD8-positivos , Diferenciación Celular , Glucólisis , Ratones , Ratones Endogámicos C57BL , Serina-Treonina Quinasas TOR/metabolismoRESUMEN
Hierodulinae is a species-rich mantid subfamily, with some species bearing a notable leaf-like pronotum. However, the evolutionary pattern and taxonomic significance of the leaf-like pronotum are largely unknown. Here, we present a phylogenomic analysis of the Hierodulinae genera Rhombodera Burmeister, 1838, and Hierodula Burmeister, 1838 based on mitochondrial genomes. We also describe a new species, namely Rhombodera hyalina sp. nov. from Guangxi, China. Our phylogenetic result, together with the evidence from male genitalia, suggests the division of the Oriental Hierodula and Rhombodera complex into three clades. We find a complex pattern on the evolution of the leaf-like pronotum, which is present in at least five lineages, respectively, of the above three clades.
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Common vetch (CV), a leguminous crop cultivated for green manure and fodder rich in protein and starch, is widespread over much area of the northern hemisphere. Its seeds can be used as a protein source to human consumption. CV protein isolates (CVPI) and major protein fractions (CV albumin protein, CVAP; CV globulin protein, CVGP; CV glutelin protein, CVGTP) from 4 samples were investigated the properties to facilitate full use of protein resources. Protein comprises 27.70 %-32.14 % of the dry CV seed weight, which is mainly composed by CVAP (26.79 %-56.12 %) and CVGP (22.78 %-52.42 %). CVPI, CVAP and CVGP mainly presented 7S and 11S components. CVGTP mainly contained the 11S component. They showed difference in thermal properties and surface hydrophobicity. Circular dichroism data showed that α-helix was their major secondary structure. CVPI and major protein fractions exhibited a U-shape protein solubility. CVPI and CVAP had advantages in emulsifying and foaming properties. This study provided novel insights on unexploited sources of CV proteins with interesting characteristics in terms of potential uses as protein-based foods.
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Fabaceae , Globulinas , Vicia sativa , Fabaceae/química , Globulinas/química , Humanos , Proteínas de Plantas/química , Semillas/química , Vicia sativa/metabolismoRESUMEN
Biomass-based porous carbon materials have attracted considerable attention because of their simple, low-cost, green, and pollution-free preparation process. Owing to their unique tubular structure and subsequent activation process, they often have a well-developed pore structure. Biomass-based carbon materials with three-dimensional hierarchical pores and polyatomic doping are regarded as promising electrode materials in the field of energy storage. In this study, cornstalk was used as the biomass and a pioneering approach was used to prepare porous carbon co-doped with N, B, and P. The B,N,P-codoped porous carbon has a three-dimensional honeycomb-like network structure with uniformly distributed and interwoven macro-, meso-, and micropores. Furthermore, it has an ultra-high specific surface area of 3123.5 m2 g-1, a high specific capacitance of 342.5 F g-1 at a current density of 0.5 A g-1, and an energy density of up to 26.18 W h kg-1. This study demonstrates a multi-element co-doping strategy that enhances the performance of cornstalk as a precursor of a supercapacitor electrode material and has important implications in the high-value-added utilisation of waste straw.
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Carbono , Biomasa , Carbono/química , Capacidad Eléctrica , Electrodos , PorosidadRESUMEN
A new route to control the microstructure and properties of carbon aerogels via vacuum impregnation is presented. The results show that the enhanced carbon aerogels exhibit uniform pore size distribution (â¼50 nm), a high compressive strength of 77.0 MPa and a low thermal conductivity of 0.15-1.62 W m-1 K-1 at 25 to 1600 °C.
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Five-hundred-watt cylindrical vector beams (CVBs) at 1030 nm with the 3 dB linewidth being less than 0.25 nm have been generated from a narrow linewidth all-fiber linearly polarized laser by metasurface extracavity conversion. At maximum output power, the transmission efficiency and polarization extinction ratio of radially polarized cylindrical vector beams (RP-CVBs) are beyond 98% and 95%, respectively. The average power is approximately an order higher than previously reported high-power narrow-linewidth CVBs generated from fiber lasers. The temperature rise of the metasurface is less than 10°C at 500 W output power, which means that the system can be further power-scaled in the near future. The high-power, high-purity, and high-efficiency RP-CVBs generated by the metasurface demonstrate potential application of a metasurface in high-power CVBs lasers.
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Gynecologic malignancies, mainly including ovarian cancer, cervical cancer and endometrial cancer, are leading causes of death among women worldwide with high incidence and mortality rate. Recently, adoptive T cell therapy (ACT) using engineered T cells redirected by genes which encode for tumor-specific T cell receptors (TCRs) or chimeric antigen receptors (CARs) has demonstrated a delightful potency in B cell lymphoma treatment. Researches impelling ACT to be applied in treating solid tumors like gynecologic tumors are ongoing. This review summarizes the preclinical research and clinical application of engineered T cells therapy for gynecologic cancer in order to arouse new thoughts for remedies of this disease.
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Tratamiento Basado en Trasplante de Células y Tejidos/métodos , Neoplasias de los Genitales Femeninos/terapia , Inmunoterapia Adoptiva/métodos , Receptores Quiméricos de Antígenos/inmunología , Linfocitos T/trasplante , Animales , Femenino , Neoplasias de los Genitales Femeninos/inmunología , Neoplasias de los Genitales Femeninos/patología , Humanos , Linfocitos T/inmunologíaRESUMEN
In this work, quasi-static mode degradation in high power fiber amplifiers has been investigated experimentally. An increase of M2 from 1.3 to 2.6 with distortion of the beam profile is observed, which results in the signal spectra and backward light characterization departing from the traditional phenomena. The amplifier has been operated at the same input pump power of 705 W for nearly 2.2 hours to investigate the relationship between quasi-static mode degradation and photodarkening. The evolution of M2 factor/beam profile, mode correlation coefficient and output laser power at different working times indicate that the quasi-static mode degradation in the high power fiber amplifiers is dependent on photodarkening and evolves on the scale of tens of minutes. A visible green light has been injected to photobleach the gain fiber for 19 hours, which reveals that the quasi-static mode degradation has been suppressed simultaneously. To the best of our knowledge, this is the first detail report of photodarkening-induced quasi-static degradation in high power fiber amplifiers.
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Listeria monocytogenes is a foodborne pathogen that causes systemic infections by crossing the intestinal barrier. However, in vitro analysis of the interaction of L. monocytogenes and small intestinal epithelium has yet to be fully elucidated. To study host responses from intestinal epithelium during L. monocytogenes infection, we used the co-culture model of small intestinal organoids and L. monocytogenes. Results showed that L. monocytogenes mediated damage to intestinal epithelium, especially intestinal stem cells. L. monocytogenes was found to reduce budding rate and increase mortality of organoids. Moreover, it affected the proliferation of epithelial cells and numbers of secretory cells. In addition, it was demonstrated that L. monocytogenes stimulated a reduction in the number of Lgr5+ stem cells. Furthermore, L. monocytogenes affected the expression of Hes1, Math1 and Sox9 to interfere with the differentiation of intestinal stem cells. Collectively, our findings reveal the effects of L. monocytogenes infection on intestinal stem cells and demonstrate that small intestinal organoid is a suitable experimental model for studying intestinal epithelium-pathogen interactions.