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Dysphagia is the most common serious complication after stroke, with an incidence of about 37-78%, which seriously affects the independence of patients in daily life and clinical recovery. Repetitive transcranial magnetic stimulation (rTMS), as a non-invasive neuromodulation technique, is an emerging option for post-stroke dysphagia. Theta burst stimulation (TBS) is a new mode of transcranial magnetic stimulation that simulates the frequency of pulses released in the hippocampus.Intermittent theta burst stimulation (iTBS) has been shown to increase cortical excitability and improve swallowing function in patients. Our study sought to summarize existing clinical randomized controlled trials to provide evidence-based medical evidence for the clinical use of iTBS. A computer search was conducted on 4 Chinese (Chinese Biomedical Literature Database, VIP Information Resource System, CNKI, and Wanfang Medical Science) and 4 English (including Cochrane Library, Embase, PubMed, Web of Science) databases to retrieve all randomized controlled trials in Chinese and English that explored the effects of Intermittent Theta Burst Stimulation for post-stroke dysphagia. The retrieval years are from database construction to 23 November 2023. The primary outcome measure was a change in Penetration/Aspiration Scale (PAS), Standardized Swallowing Assessment (SSA) and Functional Oral Intake Scale (FOIS), Secondary outcomes included Fiberoptic Endoscopic Dysphagia Severity Scale (FEDSS), water-swallowing test (WST) etc. A meta-analysis by Standardized Mean Difference (SMD) and 95% confidence interval (CI) was performed with RevMan 5.3. we appraise risk of bias(RoB) of each study with the Cochrane RoB tool. Detailed instructions for using the Cochrane RoB tool are provided in the Cochrane Handbook for Systematic Reviews of Interventions (The Cochrane Handbook). Nine studies were obtained from eight databases after screening by inclusion and exclusion criteria, 567 patients from 9 studies were included in the meta-analysis, and one study was included in the qualitative analysis due to different control groups. Two of the nine studies had an unclear risk of bias, and four studies were at low risk. The results showed that iTBS significantly improved SSA, PAS, FOIS, and PAS scores in stroke patients compared to the control group(P < 0.05), and promoted swallowing function recovery. Our systematic review provides the first evidence of the efficacy of iTBS in improving dysphagia in stroke patients. However, the number of available studies limits the persuasiveness of the evidence and further validation by additional randomized controlled trials is needed.
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Although metal halide perovskites (MHPs) have demonstrated remarkable external quantum efficiencies (EQEs) in red and green light-emitting diodes (LEDs), the blue ones confront efficiency and stability problems due to the high defect density in the perovskite films. Large amounts of defect passivation strategies are successfully developed to improve the device performance. Nevertheless, the influence of the molecular configuration of the passivators on the perovskite crystallization process has not been comprehensively investigated so far. Here, we investigate the effect of the phenyl ring on the perovskite crystallization dynamics and the passivation effect. The additive with a phenyl ring performs the π-π stacking ability with phenethylammonium (PEA+) molecules, resulting in a deteriorated crystallinity and a weakened passivation ability. Conversely, the additive without the phenyl ring is helpful to promote the participation of PEA+ molecules in the crystalline process, leading to a higher crystallinity and a stronger passivation effect. As a result, the EQE of the blue perovskite LED has increased from 4.72 to 11.06% by using the phenyl ring-free additive. Therefore, it is advisible to develop the conjugated nonplanar additives in the PEA+-assisted quasi-two-dimensional perovskites. This finding may enlighten the rational design of defect passivators for highly efficient perovskite LEDs.
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BACKGROUND: Massive hemoptysis is characterized by its life-threatening nature, potentially leading to airway obstruction and asphyxia. The objective of this study was to evaluate the clinical effectiveness of combining endobronchial tamponade with bronchial artery embolization (BAE) in the treatment of massive hemoptysis. METHODS: Between March 2018 and March 2022, a total of 67 patients with massive hemoptysis who underwent BAE were divided into two groups: the combination group (n = 26) and the BAE group (n = 41). Technical and clinical success rates were assessed, and adverse events were monitored following the treatment. Blood gas analysis and coagulation function indicators were collected before and after the treatment, and recurrence and survival rates were recorded during the follow-up period. RESULTS: All patients achieved technical success. There were no significant differences in the clinical success rate, recurrence rates at 3 and 6 months, and mortality rates at 3 months, 6 months, and 1 year between the combination group and the BAE group. However, the hemoptysis recurrence rate at 1 year was significantly lower in the combination group compared to the BAE group (15.4% vs. 39.0%, P = 0.039). No serious adverse events were reported in either group. After treatment, the combination group showed higher levels of arterial partial pressure of oxygen (PaO2), oxygenation index (PaO2/FiO2), fibrinogen (FIB), and D-dimer (D-D) compared to the BAE group (P < 0.05). Multivariate regression analysis demonstrated a significant correlation between combined therapy and hemoptysis-free survival. CONCLUSION: Combination therapy, compared to embolization alone, exhibits superior efficacy in improving respiratory function, correcting hypoxia, stopping bleeding, and preventing recurrence. It is considered an effective and safe treatment for massive hemoptysis.
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Arterias Bronquiales , Embolización Terapéutica , Hemoptisis , Humanos , Hemoptisis/terapia , Hemoptisis/etiología , Embolización Terapéutica/métodos , Femenino , Masculino , Persona de Mediana Edad , Anciano , Resultado del Tratamiento , Estudios Retrospectivos , Terapia Combinada , Adulto , Recurrencia , Broncoscopía/métodos , Análisis de los Gases de la SangreRESUMEN
Non-Abelian topological phases (NATPs) exhibit enigmatic intrinsic physics distinct from well-established Abelian topological phases, while lacking straightforward configuration and manipulation, especially for classical waves. In this Letter, we exploit novel braiding-type couplings among a pair of triple-component acoustic dipoles, which act as functional elements with effective imaginary couplings. Sequencing them in one dimension allows us to generate acoustic NATPs in a compact yet time-reversal invariant Hermitian system. We further provide the whole phase diagram that encompasses all i, j, and k non-Abelian phases, and directly demonstrate their unique quotient relations via different end point states. Our NATPs based on real-space braiding may inspire the exploration of acoustic devices with non-commutative characters.
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The stability issue of Sn-based perovskite solar cells (PSCs) is expected to be resolved by involving a two-dimensional (2D) layered structure. However, Sn-based 2D PSCs, especially Dion-Jacobson (DJ)-phase ones with potentially good stability, have rarely been reported. Herein, superior DJ-phase Sn 2D perovskites with 3-aminobenzylamine (3ABA2+) or 4-aminobenzylamine (4ABA2+) π-conjugated short-chain ligands are reported to fabricate efficient 2D lead-free PSCs. Notably, the high dipole moment of the 3ABAI2 organic spacer is approved to possess faster charge transfer for forming (3ABA)FA4Sn5I16 2D perovskite with an extremely low exciton binding energy (only 84 meV). In combination with a diacetate partial substitution and methylamine iodide/bromide (MAI/MABr) post-treatment strategy to delay crystallization and improve compactness and coverage of the perovskite film, a record power conversion efficiency (PCE) of 6.81% and stability of 840 h (less than 5% degradation in a N2 atmosphere for unencapsulated devices) are acquired in eventual (3ABA)FA4Sn5I16 2D PSCs, which are among the highest PCE and the longest stability of Sn-based 2D PSCs reported to date. Our work provides a prospective molecule design and film preparation strategy of 2D Sn perovskites toward nontoxic high-performance tin-based PSCs, which pushes the almost stagnant research forward.
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OBJECTIVES: Previous studies have demonstrated that obesity may impact the efficacy of anti-PD1 therapy, but the underlying mechanism remains unclear. In this study, our objective was to determine the prognostic value of obesity in patients with oral tongue squamous cell carcinoma (OTSCC) treated with pembrolizumab and establish a subtype based on fatty acid metabolism-related genes (FAMRGs) for immunotherapy. MATERIALS AND METHODS: We enrolled a total of 56 patients with OTSCC who underwent neoadjuvant anti-PD1 therapy. Univariate and multivariate Cox regression analyses, Kaplan-Meier survival analysis, and immunohistochemistry staining were performed. Additionally, we acquired the gene expression profiles of pan-cancer samples and conducted GSEA and KEGG pathway analysis. Moreover, data from TCGA, MSigDB, UALCAN, GEPIA and TIMER were utilized to construct the FAMRGs subtype. RESULTS: Our findings indicate that high Body Mass Index (BMI) was significantly associated with improved PFS (HR = 0.015; 95% CI, 0.001 to 0.477; p = 0.015), potentially attributed to increased infiltration of PD1 + T cells. A total of 91 differentially expressed FAMRGs were identified between the response and non-response groups in pan-cancer patients treated with immunotherapy. Of these, 6 hub FAMRGs (ACSL5, PLA2G2D, PROCA1, IL4I1, UBE2L6 and PSME1) were found to affect PD-1 expression and T cell infiltration in HNSCC, which may impact the efficacy of anti-PD1 therapy. CONCLUSION: This study demonstrates that obesity serves as a robust prognostic predictor for patients with OTSCC undergoing neoadjuvant anti-PD1 therapy. Furthermore, the expression of 6 hub FAMRGs (ACSL5, PLA2G2D, PROCA1, IL4I1, UBE2L6 and PSME1) plays a pivotal role in the context of anti-PD1 therapy and deserves further investigation.
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Inhibidores de Puntos de Control Inmunológico , Terapia Neoadyuvante , Obesidad , Neoplasias de la Lengua , Humanos , Neoplasias de la Lengua/tratamiento farmacológico , Neoplasias de la Lengua/metabolismo , Neoplasias de la Lengua/inmunología , Neoplasias de la Lengua/patología , Neoplasias de la Lengua/mortalidad , Neoplasias de la Lengua/genética , Femenino , Masculino , Terapia Neoadyuvante/métodos , Obesidad/metabolismo , Obesidad/complicaciones , Persona de Mediana Edad , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Pronóstico , Anciano , Carcinoma de Células Escamosas de Cabeza y Cuello/tratamiento farmacológico , Carcinoma de Células Escamosas de Cabeza y Cuello/inmunología , Carcinoma de Células Escamosas de Cabeza y Cuello/mortalidad , Carcinoma de Células Escamosas de Cabeza y Cuello/metabolismo , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Carcinoma de Células Escamosas de Cabeza y Cuello/terapia , Anticuerpos Monoclonales Humanizados/uso terapéutico , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Receptor de Muerte Celular Programada 1/metabolismo , Adulto , Índice de Masa Corporal , Biomarcadores de Tumor/metabolismoRESUMEN
Objective: To observe the efficacy of Guiqi Erxian granule on chemotherapy-related fatigue in patients with lung cancer treated with chemotherapy. Methods: A total of 76 lung cancer patients with chemotherapy-related fatigue as the main symptom from January 2017 to May 2018 were enrolled and randomly divided into a control group and a treatment group, n = 38/group. The patients in the control group received chemotherapy and basic treatment. The patients in the treatment group received oral Guiqi Erxian granule 20 g each time, three times daily, in addition to the chemotherapy and basic treatment. The brief fatigue inventory (BFI) scale, Cancer Fatigue Scale (CFS), chronic illness therapy fatigue scale, and traditional Chinese medicine (TCM) symptom scale were evaluated on 1 day before treatment, and on day 7 and day 14 of treatment. Adverse reactions were observed and recorded. Results: Compared to the control group, the total score and scores of each dimension of the BFI and CFS decreased in the treatment group; the effect on fatigue severity and fatigue impact scores in the BFI scale, and the emotional and physical dimension scores in the CFS were improved significantly (P < .05). Compared to the control group, except for the social/family well-being, the scores in the other dimensions of the chronic illness therapy-fatigue scale improved significantly (P < .05). Compared to the control group, the TCM syndrome score in the treatment group decreased significantly (P < .05). Conclusion: Guiqi Erxian granules can improve chemotherapy-related fatigue and quality of life in lung cancer patients receiving chemotherapy, with no obvious side effects, and can be explored as a potential treatment.
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The mapping of long-wavelength phonons is important to understand and manipulate the thermal transport in multilayered structures, but it remains a long-standing challenge due to the collective behaviors of phonons. In this study, an experimental demonstration of mapping the long-wavelength phonons in an alloyed Al0.1Ga0.9As/Al0.9Ga0.1As superlattice system is reported. Multiple strategies to filter out the short- to mid-wavelength phonons are used. The phonon mean-free-path-dependent thermal transport properties directly demonstrate both the suppression effect of the ErAs nanoislands and the contribution of long-wavelength phonons. The contribution from phonons with mean free path longer than 1 µm is clearly demonstrated. A model based on the Boltzmann transport equation is proposed to calculate and describe the thermal transport properties, which depicts a clear physical picture of the transport mechanisms. This method can be extended to map different wavelength phonons and become a universal strategy to explore their thermal transport in various application scenarios.
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Gradual pollen presentation is a plant reproductive mechanism to improve pollination efficiency and accuracy and promote outcrossing. Vaccinium corymbosum 'Bluecrop' has a typical gradual pollen presentation mechanism. 'Bluecrop' exhibits an inverted bell-shaped flower with a white coloration. By investigating the flower syndrome, pollination characteristics, pollination efficiency, and breeding system of 'Bluecrop', this study aims to explore the adaptive significance of these traits. The results showed 'Bluecrop' released pollen gradually through anther poricidal dehiscence. Among different pollinators, Apis mellifera and Bombus can pollinate effectively, and the mechanism of gradual pollen presentation significantly improved the efficiency of pollen transfer. This characteristic limits the amount of pollen removed by the pollinators and prolongs pollen presentation, thus attracting more pollinators and thereby increasing male fitness. The nectar secretion of 'Bluecrop' is gradual, with a large nectar production and a long phase of nectar secretion, enhance visitation frequencies and the chances of successful pollination. At the same time, campanulate corolla can protect pollen as well as nectar from waste due to environmental factors and other effects. The breeding system of 'Bluecrop' relies mainly on outcrossing because of its low affinity for self-fertilization and good interaction with pollinating insects. Thus, the special floral syndrome and the mechanism of secondary pollen presentation are significant in improving pollination efficiency and promoting the reproductive success of 'Bluecrop' by outcrossing. It can provide a certain theoretical basis for the future propagation breeding of 'Bluecrop'.
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Flores , Polen , Polinización , Abejas/fisiología , Flores/genética , Flores/fisiología , Animales , Arándanos Azules (Planta) , Néctar de las Plantas , FitomejoramientoRESUMEN
In order to safeguard the surface structures from mining damage while optimizing the liberation of coal resources under the dense surface buildings of the Cedi River coal mine. Considering that the analysis of the structure and type of surface buildings and the geological mining conditions of the mine, a wide strip mining design with a retention width of 70 m and a mining width of 50 m was finally determined by using the pressure arch theory and Wilson's theory, combined with the actual layout of working faces 51,002, 51,004 and 51,006 at the site.The strip mining design is verified by probability integral method and FLAC3D numerical simulation calculation respectively, The findings indicate that the highest value of earth surface subsidence created by the mining of the wide strip is 210 mm, the surface horizontal deformation value is 1.0 to - 1.4 mm/m, the damage to surface buildings is less than Level I, which satisfying the prerequisites of the surface building protection level, and can realize the continuous advancement of mine 51,002, 51,004 and 51,006 working faces, The coal pillars of the retained strip have sufficient support strength and long-term consistency, and the movement and deformation of the overburden after mining will not cause undulating subsidence of the surface, which effectively solve the mine's technical difficulties in safely coal mining under surface buildings.
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During the synthesis of deep-blue perovskite quantum dots (PQDs), they generally emerge as a two-dimensional byproduct with poor yield and low photoluminescence quantum yield (PLQY) due to amine ligand enrichment-induced abundant surface defects. Herein, we provide a colloidal synthesis method to prepare deep-blue CsPbBr3 PQDs in a green nontoxic solvent via strategic Z-type ligand engineering. Z-type ligands of zinc octanoate enable the formation of robust coordination bonds with surface bromide ions of PQDs, maintaining acid-base equilibrium and reducing excess amine enrichment on the PQDs surface. Consequently, homogeneous and monodispersed PQDs with improved PLQY of 73% are successfully synthesized, achieving efficient deep-blue LEDs with a peak EQE of 5.46%, a maximum luminance of 847.6 cd/m2, and an operational half-lifetime of 14 min. The devices exhibit color coordinates of (0.137, 0.049), closely approximating the Rec. 2020 blue standard. Our work offers a potentially eco-friendly and viable route for realizing high-performance LEDs in the deep-blue region.
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This communication describes an effective morphological control strategy involving introducing two-dimensional (2D) Cs3Sb2Br9 to induce a transformation of three-dimensional (3D) CsPbBr3 to 2D nanoplates (NPLs). By tuning the Sb/Pb ratio, 2D CsPbBr3 NPLs exhibiting a deep-blue emission centered at a wavelength of 464 nm with an FWHM of 24 nm have been produced. The absence of organic ligands in these high-quality 2D NPLs mitigate the instability issue induced by organic ligand migration and penetration, and these NPLs exhibit 80% of the initial PL intensity after 55 days.
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Sodium butyrate (NaB) has garnered attention in recent years for its ability to impede the malignant progression of tumors. In order to explore the potential inhibitory effects of NaB on the replication of Marek's disease virus (MDV) and subsequent lymphoma formation, newly hatched chickens were infected with the vvMDV Md5 strain and administered NaB prior to (prevention group) or following (treatment group) Md5 inoculation. The results revealed that NaB played a pivotal role in diminishing both the incidence and fatality rates in chickens afflicted with Md5 infection. Notably, NaB exhibited a remarkable capacity to inhibit the expression of MDV immediate early genes, i.e., ICP4 and ICP27, thus attenuating tumorigenesis in the chicken spleen. To further elucidate the mechanism of NaB on lymphoma cells, MDV bearing lymphoma cells, i.e., MSB-1 were exposed to NaB for 24 h prior to various experimental tests. The results revealed that NaB effectively hindered the proliferation, migration, and colony formation of MSB-1 cells. Furthermore, NaB demonstrated the ability to modulate the key molecules in mitochondrial apoptosis pathway. Taken together, these findings reveal that NaB can impede the lymphoma caused by MDV via regulating the mitochondrial apoptosis pathway, both in vitro and in vivo. These results suggest that the utilization of NaB warrants serious consideration as a promising approach for the prevention of MDV.
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OBJECTIVES: This study aimed to construct a radiomics-based model for prognosis and benefit prediction of concurrent chemoradiotherapy (CCRT) versus intensity-modulated radiotherapy (IMRT) in locoregionally advanced nasopharyngeal carcinoma (LANPC) following induction chemotherapy (IC). MATERIALS AND METHODS: A cohort of 718 LANPC patients treated with IC + IMRT or IC + CCRT were retrospectively enrolled and assigned to a training set (n = 503) and a validation set (n = 215). Radiomic features were extracted from pre-IC and post-IC MRI. After feature selection, a delta-radiomics signature was built with LASSO-Cox regression. A nomogram incorporating independent clinical indicators and the delta-radiomics signature was then developed and evaluated for calibration and discrimination. Risk stratification by the nomogram was evaluated with Kaplan-Meier methods. RESULTS: The delta-radiomics signature, which comprised 19 selected features, was independently associated with prognosis. The nomogram, composed of the delta-radiomics signature, age, T category, N category, treatment, and pre-treatment EBV DNA, showed great calibration and discrimination with an area under the receiver operator characteristic curve of 0.80 (95% CI 0.75-0.85) and 0.75 (95% CI 0.64-0.85) in the training and validation sets. Risk stratification by the nomogram, excluding the treatment factor, resulted in two groups with distinct overall survival. Significantly better outcomes were observed in the high-risk patients with IC + CCRT compared to those with IC + IMRT, while comparable outcomes between IC + IMRT and IC + CCRT were shown for low-risk patients. CONCLUSION: The radiomics-based nomogram can predict prognosis and survival benefits from concurrent chemotherapy for LANPC following IC. Low-risk patients determined by the nomogram may be potential candidates for omitting concurrent chemotherapy during IMRT. CLINICAL RELEVANCE STATEMENT: The radiomics-based nomogram was constructed for risk stratification and patient selection. It can help guide clinical decision-making for patients with locoregionally advanced nasopharyngeal carcinoma following induction chemotherapy, and avoid unnecessary toxicity caused by overtreatment. KEY POINTS: ⢠The benefits from concurrent chemotherapy remained controversial for locoregionally advanced nasopharyngeal carcinoma following induction chemotherapy. ⢠Radiomics-based nomogram achieved prognosis and benefits prediction of concurrent chemotherapy. ⢠Low-risk patients defined by the nomogram were candidates for de-intensification.
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Chiral anomaly bulk states (CABSs) can be realized by choosing appropriate boundary conditions in a finite-size waveguide composed of two-dimensional Dirac semimetals, which have unidirectional and robust transport similar to that of valley edge states. CABSs use almost all available guiding space, which greatly improves the utilization of metamaterials. Here, free-boundary-induced CABSs in elastic twisted kagome metamaterials with C_{3v} symmetry are experimentally confirmed. The robust valley-locked transport and complete valley state conversion are experimentally observed. Importantly, the sign of the group velocity near the K and K^{'} points can be reversed by suspending masses at the boundary to manipulate the onsite potential. Moreover, CABSs are demonstrated in nanoelectromechanical phononic crystals by constructing an impedance-mismatched hard boundary. These results open new possibilities for designing more compact, space-efficient, and robust elastic wave macro- and microfunctional devices.
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In this study, gold nanocubes (AuNCs) were quickly synthesized using the seed-mediated growth method and reduced onto the surface of two-dimensional (2D) delaminated nano mica platelets (NMPs), enabling the development of AuNCs/NMPs nanohybrids with a 3D lightning-rod effect. First, the growth-solution amount can be changed to easily adjust the AuNCs average-particle size within a range of 30-70 nm. The use of the cationic surfactant cetyltrimethylammonium chloride as a protective agent allowed the surface of AuNCs and nanohybrids to be positively charged. Positively charged nanohybrid surfaces presented a good adsorption effect for detecting molecules with negative charges on the surface. Additionally, the NMP surfaces were rich in ionic charges and provided a large specific surface area for stabilizing the growth of AuNCs. Delaminated AuNCs/NMPs nanohybrids can generate a 3D hotspot effect through self-assembly to enhance the Raman signal. Surface-enhanced Raman scattering (SERS) is highly sensitive in detecting adenine biomolecules. Its limit of detection (LOD) and Raman enhancement factor reached 10-9 M and 3.6 × 108, respectively. Excellent reproducibility was obtained owing to the relatively regular arrangement of AuNC particles, and the relative standard deviation (RSD) was 10.7%. Finally, the surface of NMPs was modified by adding the hydrophilic poly(oxyethylene)-diamine (POE2000) and amphiphilic PIB-POE-PIB copolymer at different weight ratios. The adjustment of the surface hydrophilicity and hydrophobicity of AuNCs/NMPs nanohybrids led to better adsorption and selectivity for bacteria. AuNCs/POE/NMPs and AuNCs/PIB-POE-PIB/NMPs were further applied to the SERS detection of hydrophilic Staphylococcus aureus and hydrophobic Escherichia coli, respectively. The SERS-detection results suggest that the LOD of hydrophilic Staphylococcus aureus and hydrophobic Escherichia coli reached 92 CFU mL-1 and 1.6 × 102 CFU mL-1, respectively. The AuNCs/POE/NMPs and AuNCs/PIB-POE-PIB/NMPs nanohybrids had different hydrophilic-hydrophobic affinities, which greatly improved the selectivity and sensitivity for detecting bacteria with different hydrophilicity and hydrophobicity. Therefore, fast, highly selective, and highly sensitive SERS biological-detection results were obtained.
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Silicatos de Aluminio , Técnicas Biosensibles , Relámpago , Oro/química , Espectrometría Raman/métodos , Reproducibilidad de los Resultados , Staphylococcus aureus , Escherichia coliRESUMEN
Benthic freshwater cyanobacteria have the potential to produce toxins. Compared with more extensively studied plankton species, little is known about the impact of harmful benthic cyanobacteria on aquatic organisms. As demersal fish are usually in direct contact with benthic cyanobacteria, it is important to understand their interactive effects. This study investigated the physio-chemical responses of two demersal fish (Xenocypris davidi and Crucian carp) after exposure to benthic Oscillatoria (producing cylindrospermopsin, 2 × 106 cells/mL) for 7 days. Interestingly, benthic Oscillatoria had less adverse effects on X. davidi than C. carp. The two demersal fish effectively ingested Oscillatoria, but Oscillatoria cell sheathes could not be fully digested in C. carp intestines and led to growth inhibition. Oscillatoria consumption induced oxidative stress and triggered alterations in detoxification enzyme activities in the X. davidi liver. Superoxide dismutase (SOD) and glutathione reductase (GR) activities significantly increased in the C. carp liver, but catalase (CAT) and detoxification enzymes glutathione S-transferase (GST) and glutathione (GSH) activities were insignificantly changed. This suggested that C. carp may have a relatively weak detoxification capacity for toxic Oscillatoria. Oscillatoria ingestion led to more pronounced liver pathological changes in C. carp, including swelling, deformation, and loss of cytoskeleton structure. Simultaneously, fish consumption of Oscillatoria increased extracellular cylindrospermopsin concentration. These results provide valuable insights into the ecological risks associated with benthic cyanobacteria in aquatic ecosystems.
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Toxinas Bacterianas , Carpas , Toxinas de Cianobacterias , Hígado , Estrés Oxidativo , Animales , Hígado/patología , Toxinas Bacterianas/toxicidad , Cianobacterias , Antioxidantes/metabolismo , Alcaloides , Oscillatoria , Uracilo/análogos & derivados , Uracilo/toxicidad , Superóxido Dismutasa/metabolismo , Toxinas Marinas/toxicidadRESUMEN
Vertically stacked multiple atomically thin layers have recently widened the landscape of rich optical structures thanks to these quantum metamaterials or van der Waals (vdW) materials, featuring hyperbolic polaritons with unprecedented avenues for light. Despite their far-reaching implications, most of their properties rest entirely on a trivial band topological origin. Here, a 2D approach is adopted toward a micromechanical vdW analogue that, as a result of engineered chiral and mirror symmetries, provides topologically resilient hyperbolic radiation of mechanical vibrations in the ultrasonic regime. By applying laser vibrometry of the micrometer-sized metasurface, we are able to exhibit the exotic fingerprints of robust hyperbolic radiation spanning several frequencies, which beyond their physical relevance, may enable ultrasonic technologies.
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Coherent phonon transfer via high-quality factor (Q) mechanical resonator strong coupling has garnered significant interest. Yet, the practical applications of these strongly coupled resonator devices are largely constrained by their vulnerability to fabrication defects. In this study, topological strong coupling of gigahertz frequency surface acoustic wave (SAW) resonators with lithium niobate is achieved. The nanoscale grooves are etched onto the lithium niobate surface to establish robust SAW topological interface states (TISs). By constructing phononic crystal (PnC) heterostructures, a strong coupling of two SAW TISs, achieving a maximum Rabi splitting of 22 MHz and frequency quality factor product fQm of ≈1.2 × 1013 Hz, is realized. This coupling can be tuned by adjusting geometric parameters and a distinct spectral anticrossing is experimentally observed. Furthermore, a dense wavelength division multiplexing device based on the coupling of multiple TISs is demonstrated. These findings open new avenues for the development of practical topological acoustic devices for on-chip sensing, filtering, phonon entanglement, and beyond.
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The present study was conducted to prepare and investigate large-area, high-sensitivity surface-enhanced Raman scattering (SERS) substrates. Organic/inorganic nanohybrid dispersants consisting of an amphiphilic triblock copolymer (hereafter referred to simply as "copolymer") and graphene oxide (GO) were used to stabilize the growth and size of gold nanoparticles (AuNPs). Ion-dipole forces were present between the AuNPs and copolymer dispersants, while the hydrogen bonds between GO and the copolymer prevented the aggregation of GO, thereby stabilizing the AuNP/GO nanohybrids. Transmission electron microscopy (TEM) revealed that the AuNPs had particle sizes of 25-35 nm and a relatively uniform size distribution. The AuNP/GO nanohybrids were deposited onto the glass substrate by using the solution drop-casting method and employed for SERS detection. The self-assembling properties of two-dimensional sheet-like GO led to a regular lamellar arrangement of AuNP/GO nanohybrids, which could be used for the preparation of large-area SERS substrates. Following removal of the copolymer by annealing at 300 °C for 2 h, measurements were obtained under scanning electron microscopy. The results confirmed that 2D GO nanosheets were capable of stabilizing AuNPs, with the final size reaching approximately 40 nm. These AuNPs were adsorbed on both sides of the GO nanosheets. Because the GO nanosheets were merely 5 nm-thick, a good three-dimensional hot-junction effect was generated along the z-axis of the AuNPs. Lastly, the prepared material was used for the SERS detection of rhodamine 6G (R6G), a commonly used highly fluorescent dye. An enhancement factor (EF) of up to 3.5 × 106 was achieved, and the limit of detection was approximately 10-10 M. Detection limits of 10-10 M and < 10-10 M were also observed with the detection of Direct Blue 200 and the biological molecule adenine. It is therefore evident that AuNP/copolymer/GO nanohybrids are large-area flexible SERS substrates that hold great potential in environmental monitoring and biological system detection applications.