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Surface enhanced Raman spectroscopy (SERS) is a highly sensitive analytical detection method commonly employed in biochemical and environmental analysis. Nevertheless, the rapid movement of analytes and interfering components in flow systems can impact the real-time, online detection capability of Raman spectroscopy. To address this issue, we developed an innovative approach utilizing covalent organic framework (COF), a robust porous material with excellent water stability, to coat the surface of Ag nanowire (AgNW) for synthesizing AgNW@COF hybrid. The regular pores of the COF serve to effectively eliminate large interfering molecules while facilitating the efficient transport of specific analytes to SERS hot spots. Additionally, the fluid flow-induced scouring effect aids in excluding interfering molecules from the surface of AgNW. By incorporating AgNW@COF into a bifunctional filter membrane with simultaneous filtration and sensing capabilities, we had achieved efficient purification of organic pollutants as well as real-time identification of pollutant species and concentration.
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Objective: To compare the difference in the effectiveness of ranibizumab (LU) and aflibercept (AF) in the treatment of diabetic retinopathy (DR). Methods: Ninety-four patients with DR admitted to Sunshine Union Hospital from August 2020 to February 2022 were selected for the study and were divided into LU group (n = 47) and AF group (n = 47) according to the random number table method. Both groups underwent 25G vitrectomy in our hospital, with LU injected into the vitreous before surgery in the LU group and AF in the AF group. Vascular endothelial growth factor (VEGF) and pigment epithelium-derived factor (PEDF) in the pre-and post-injection atrial water were compared between the two groups, and the operative time, intraoperative bleeding, and the occurrence of medically induced fissures were recorded in both groups. In addition, the expression of best corrected visual acuity (BCVA), Central Macular Thickness (CMT), and inflammatory factors were compared before and after surgery. Finally, patients were counted for adverse reactions and prognosis of DR recurrence during treatment. Results: After injection, VEGF decreased and PEDF increased in both groups (P < .001). There were no differences in operative time (P = .604), intraoperative bleeding rate (P = .694), the incidence of medically induced fissure (P = .557), BCVA [P = .665 (T0), P > .999 (T1), P = .727 (T2)], and CMT [P = .688 (T0), P = .065 (T1), P = .148 (T2)] between the two groups, while IL-6, IL-8, and MMP-9 were lower in the AF group than in the LU group at 2 months after surgery (P < .001). Finally, there was no difference between both groups in terms of adverse effects and prognosis of DR recurrence rate (P = 1.000, .478). Conclusion: Both vitreous cavity injections of LU and AF can effectively reduce the expression of vascular-related factors in the atrial fluid of DR patients, but AF has a more significant inhibitory effect on the level of inflammatory factors in patients in the short term after treatment.
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Diabetes Mellitus , Retinopatía Diabética , Receptores de Factores de Crecimiento Endotelial Vascular , Proteínas Recombinantes de Fusión , Humanos , Ranibizumab/uso terapéutico , Retinopatía Diabética/tratamiento farmacológico , Retinopatía Diabética/inducido químicamente , Factor A de Crecimiento Endotelial Vascular/uso terapéutico , Inhibidores de la Angiogénesis/uso terapéutico , Resultado del TratamientoRESUMEN
Hazardous object detection (escalators, stairs, glass doors, etc.) and avoidance are critical functional safety modules for autonomous mobile cleaning robots. Conventional object detectors have less accuracy for detecting low-feature hazardous objects and have miss detection, and the false classification ratio is high when the object is under occlusion. Miss detection or false classification of hazardous objects poses an operational safety issue for mobile robots. This work presents a deep-learning-based context-aware multi-level information fusion framework for autonomous mobile cleaning robots to detect and avoid hazardous objects with a higher confidence level, even if the object is under occlusion. First, the image-level-contextual-encoding module was proposed and incorporated with the Faster RCNN ResNet 50 object detector model to improve the low-featured and occluded hazardous object detection in an indoor environment. Further, a safe-distance-estimation function was proposed to avoid hazardous objects. It computes the distance of the hazardous object from the robot's position and steers the robot into a safer zone using detection results and object depth data. The proposed framework was trained with a custom image dataset using fine-tuning techniques and tested in real-time with an in-house-developed mobile cleaning robot, BELUGA. The experimental results show that the proposed algorithm detected the low-featured and occluded hazardous object with a higher confidence level than the conventional object detector and scored an average detection accuracy of 88.71%.
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Many diseases involve either the formation of new blood vessels (e.g., tumor angiogenesis) or the damage of existing ones (e.g., diabetic retinopathy) at the microcirculation level. Optical-resolution photoacoustic microscopy (OR-PAM), capable of imaging microvessels in 3D in vivo down to individual capillaries using endogenous contrast, has the potential to reveal microvascular information critical to the diagnosis and staging of microcirculation-related diseases. In this study, we have developed a dedicated microvascular quantification (MQ) algorithm for OR-PAM to automatically quantify multiple microvascular morphological parameters in parallel, including the vessel diameter distribution, the microvessel density, the vascular tortuosity, and the fractal dimension. The algorithm has been tested on in vivo OR-PAM images of a healthy mouse, demonstrating high accuracy for microvascular segmentation and quantification. The developed MQ algorithm for OR-PAM may greatly facilitate quantitative imaging of tumor angiogenesis and many other microcirculation related diseases in vivo.
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Algoritmos , Diagnóstico por Imagen de Elasticidad/métodos , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Microvasos/diagnóstico por imagen , Animales , Ratones , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
This work presents the development and systematic study of a method to prepare hierarchical titanium silicalite-1 (TS-1) zeolites with high tetra-coordinated framework Ti species content. The new method involves (i) the synthesis of the aged dry gel by treating the zeolite precursor at 90 °C for 24 h; and (ii) the synthesis of hierarchical TS-1 by treating the aged dry gel using tetrapropylammonium hydroxide (TPAOH) solution under hydrothermal conditions. Systematic studies were conducted to understand the effect of the synthesis conditions (including the TPAOH concentration, liquid-to-solid ratio, and treatment time) on the physiochemical properties of the resulting TS-1 zeolites, and the results showed that the condition of a TPAOH concentration of 0.1 M, liquid-to-solid ratio of 1.0, and treatment time of 9 h was ideal to enable the synthesis of hierarchical TS-1 with a Si/Ti ratio of 44. Importantly, the aged dry gel was beneficial to the quick crystallization of zeolite and assembly of nanosized TS-1 crystals with a hierarchical structure (S ext = 315 m2 g-1 and V meso = 0.70 cm3 g-1, respectively) and high framework Ti Species content, making the accessible active sites ready for promoting oxidation catalysis.
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The Pennsylvanian is characterized by intense paleoenvironmental changes related to glacio-eustatic sea-level fluctuations and major tectonic events, which affected the evolution of biocommunities. Most known Pennsylvanian tropical reefs and mounds are predominantly composed of calcareous algae (e.g. phylloid algae, Archaeolithophyllum), calcareous sponges, fenestrate bryozoans, Tubiphytes, and microbialites. However, in Houchang (southern China), the Late Pennsylvanian carbonate platform records a large coral reef lacking any analogs in age (Gzhelian), size (80-100 m thick) and composition (high biodiversity). The large coral reef developed at the border of the Luodian intraplatform basin. The intraplatform basin is characterized by the deposition of green algal grainstone, coated grain grainstone and bioclastic packstone, grainstone, floatstone and rudstone in shallow-waters. In the deep-water shelf, lithofacies are composed of burrowed bioclastic wackestone, microbioclastic peloidal packstone, grainstone, and fine-grained burrowed wackestone and packstone. In this context, the coral reef developed on a deep-shelf margin, in a moderate to low energy depositional environment, below the FWWB. The scarcity of Pennsylvanian coral reefs suggests global unfavorable conditions, which can be attributed to a complex pattern of several environmental factors, including seawater chemistry (aragonite seas), paleoclimatic cooling related to continental glaciation, and the biological competition with the more opportunistic and adaptive phylloid algal community that occupied similar platform margin paleoenvironments. The existence of the large Bianping coral reef in southern China, as well as a few additional examples of Pennsylvanian coralliferous bioconstructions, provides evidence that coral communities were able to endure the Late Paleozoic fluctuating paleoenvironmental conditions in specific settings. One of such settings appears to have been the deep shelf margin, where low light levels decreased competition with the phylloid algal community.
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Intracellular pH (pHi) plays a crucial role in cell physiological and pathological processes. We herein report an efficient pH-sensitive sensor based on two-photon excitable semiconducting polymer nanoparticles (PFV/PSMA-DA NPs) for pHi sensing. PFV/PSMA NPs were functionalized with redox-active dopamine (DA) and the obtained PFV/PSMA-DA NPs showed sensitive and reversible pH response over the pH range of 5.0-9.0. Owning to the high biocompatibility and pH-responsive DA, PFV/PSMA-DA NPs show low cytotoxicity and the quantification and imaging of intracellular pH changes of HeLa cells were successfully realized. Moreover, the detection of intracellular pH fluctuation induced by redox species such as NAC (N-acetylcysteine) and H2O2 was also achieved by both one- and two-photon excitation of the PFV/PSMA-DA NPs probe. This work clearly shows that nanoprobe based on two-photon PFV/PSMA-DA NPs could serve as a promising platform for quantitatively monitoring the intracellular pH fluctuations.
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Técnicas Biosensibles/métodos , Indoles/química , Anhídridos Maleicos/química , Nanopartículas/química , Polímeros/química , Poliestirenos/química , Semiconductores , Células HeLa , Humanos , Concentración de Iones de Hidrógeno , FotonesRESUMEN
Highly stable semiconducting polymer nanoparticles (NPs) (poly(9,9-dioctylfluorenyl-2,7-diyl) (PFO)/ poly(fluorene-2,7-ylenevinylene-co-phenylene) (PFV)-dopamine (DA) NPs) with previously unreported core-shell structure are developed for ratiometric sensing of intracellular pH values. PFO/PFV-DA NPs comprise central polyfluorene (PFO) as donor and PFV as acceptor, in which the donor and acceptor are spatially separated into the central core and nanoparticle shell. Specifically, thick PFV shells can not only significantly minimize the quenching interference of dopamine on the emission of standard reference (PFO), but are also able to maximize its accessibility to pH-sensitive dopamine and lead to sensitive response to pH changes. The resulting core-shell PFO/PFV NPs are structurally and optically stable, which can avoid the photobleaching and leakage of materials issues compared to traditional semiconducting polymer nanoparticles (SPNs)-based fluorescence resonance energy transfer (FRET) systems containing small molecules. Additionally, the designed compact PFO/PFV-DA NPs show quantitative response to the pH values in aqueous media and are capable of mapping intracellular pH fluctuations by ratiometric imaging. This work may open up opportunities for the generalizability of the consistent ratiometric emission intensity strategy based on core-shell structured SPNs nanoprobes for highly sensitive biological sensing.
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Transferencia Resonante de Energía de Fluorescencia , Imagenología Tridimensional , Espacio Intracelular/química , Nanopartículas/química , Polímeros/química , Supervivencia Celular/efectos de los fármacos , Dexametasona/farmacología , Dopamina/química , Fluorenos/síntesis química , Fluorenos/química , Células HeLa , Humanos , Concentración de Iones de Hidrógeno , Nanopartículas/ultraestructura , Polímeros/síntesis química , Espectrometría de FluorescenciaRESUMEN
Objective@#To improve physical activity by assessing pedometer-based physical activity during specific intervals over a week, among junior high school students,and to provide a reference for improving the level of students’ physical activity.@*Methods@#Students (n=675) of grades 6-8 from six public junior high schools in Shanghai were recruited and instructed to wear a pedometer for a week, step counts and contents were recorded over a specific period. This period mainly included steps taken on the way to and from school, at school, at home in the evening on weekdays, and in the morning, afternoon, and evening on weekends.@*Results@#The daily step counts recorded were 8 332 steps, with those on weekdays showing significantly higher values than step counts on weekends (9 065 steps vs. 6 392 steps)(t=22.9, P<0.01). Proportionately, the physical activity level at school contributed more to daily step counts (61.3%), followed by those on the commute to and from school(25.5%). Boys were more active than girls. For all intervals on weekdays, the step counts of students in rural districts, with overweight or obese, in grades 6 and 7, were higher than those in urban districts, with normal status, in grade 8 respectively (P<0.05). Low-activity students with physical education were more active than one without physical education(t boy=1.99,t girl=2.45,P<0.05).@*Conclusion@#These findings facilitate the implementation of effective, feasible interventions to enhance physical activity over a series of intervals during the day.