Combination of microporous hollow carbon spheres and nafion for the individual metal-free stripping detectionof Pb2+ and Cd2+

Here, the combination of Nafion with microporous hollow carbon spheres (MHCS) is first proposed to fabricate a disposable metal-free electrode for heavy metal stripping sensing. The MHCS-Nafion composite film electrode is prepared by drop-casting a mixture of MHCS and Nafion onto the lab-made screen-printed carbon electrode (SPCE*). Results demonstrate that the interfusion of MHCS into Nafion offers enhanced performance for the electro-enrichment and stripping of lead and cadmium over the only Nafion film: 1) abundant MHCS immobilized on the electrode surface serve as effective nucleation sites for metal ion reduction; 2) the mixing of MHCS into Nafion enlarges the active surface of negative-charged Nafion for the electrostatic adsorption of metal cations. The proposed MHCS-Nafion/SPCE* provides linear responses for Pb2+ and Cd2+ in the range of 2 - 200 mu g/L, with a detection limit of 1.37 and 1.63 mu g/L, respectively. Practical applications of the sensor in water sample detection with good accuracy have also been confirmed

Prioritized Planning for Target-Oriented Manipulation via Hierarchical Stacking Relationship Prediction

In scenarios involving the grasping of multiple targets, the learning of stacking relationships between objects is fundamental for robots to execute safely and efficiently. However, current methods lack subdivision for the hierarchy of stacking relationship types. In scenes where objects are mostly stacked in an orderly manner, they are incapable of performing human-like and high-efficient grasping decisions. This paper proposes a perception-planning method to distinguish different stacking types between objects and generate prioritized manipulation order decisions based on given target designations. We utilize a Hierarchical Stacking Relationship Network (HSRN) to discriminate the hierarchy of stacking and generate a refined Stacking Relationship Tree (SRT) for relationship description. Considering that objects with high stacking stability can be grasped together if necessary, we introduce an elaborate decision-making planner based on the Partially Observable Markov Decision Process (POMDP), which leverages observations and generates the least grasp-consuming decision chain with robustness and is suitable for simultaneously specifying multiple targets. To verify our work, we set the scene to the dining table and augment the REGRAD dataset with a set of common tableware models for network training. Experiments show that our method effectively generates grasping decisions that conform to human requirements, and improves the implementation efficiency compared with existing methods on the basis of guaranteeing the success rate.Comment: 8 pages, 8 figure

Enzyme- and metal-free electrochemical sensor for highly sensitive superoxide anion detection based on nitrogen doped hollow mesoporous carbon spheres

In this work, a highly sensitive enzyme- and metal-free electrochemical method for superoxide anion (O[rad]) detection has been developed by employing screen-printed carbon electrodes (SPCE) modified by nitrogen doped hollow mesoporous carbon spheres (N-HMCS). For comparison, solid carbon spheres (SCS) and hollow mesoporous carbon spheres (HMCS) were also synthesized to fabricate the modified SPCE. Compared with SCS/SPCE and HMCS/SPCE, N-HMCS/SPCE displayed a higher electrochemical performance. When applied for electrochemical detection of O[rad], N-HMCS/SPCE exhibited a high sensitivity of 1.49\ua0μA\ua0cm\ua0μM, better than SCS/SPCE and HMCS/SPCE and many of enzyme- or metal-based superoxide anion sensors. N-HMCS is expected to become a new generation of sensing materials for electrochemical analysis of O[rad]

Specific and sensitive detection of the guava fruit anthracnose pathogen (Colletotrichum gloeosporioides) by loop-mediated isothermal amplification (LAMP) assay

Anthracnose of guava, caused by the fungus Colletotrichum gloeosporioides, is a major factor limiting worldwide guava production. Timely and accurate detection of the pathogen is important in developing a disease management strategy. Herein, a loop-mediated isothermal amplification (LAMP) assay for the specific and sensitive detection of C. gloeosporioides was developed using primers targeting the β-tubulin 2 (TUB2) gene. The optimal reaction conditions were 64 °C for 60 min. The specificity of the method was tested against C. gloeosporioides isolates, Colletotrichum spp. isolates, and isolates of other genera. Positive results were obtained only in the presence of C. gloeosporioides, whereas no cross-reaction was observed for other species. The detection limit of the LAMP assay was 10 fg of genomic DNA in a 25 μL reaction. The LAMP assay successfully detected C. gloeosporioides in guava fruit collected in the field. The results indicate that the developed LAMP assay is a simple, cost-effective, rapid, highly sensitive, and specific tool for the diagnosis of guava anthracnose caused by C. gloeosporioides and could be useful for disease management.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Dendritic mesoporous silica nanoparticles with abundant Ti4+ for phosphopeptide enrichment from cancer cells with 96% specificity

Selective enrichment and sensitive detection of phosphopeptides are of great significance in many bio-applications. In this work, dendritic mesoporous silica nanoparticles modified with polydopamine and chelated Ti (denoted DMSNs@PDA-Ti) were developed to improve the enrichment selectivity of phosphopeptides. The unique central-radial pore structures endowed DMSNs@PDA-Ti with a high surface area (362 m g), a large pore volume (1.37 cm g) and a high amount of chelated Ti (75 μg mg). Compared with conventional mesoporous silica-based materials with the same functionalization (denoted mSiO@PDA-Ti) and commercial TiO, DMSNs@PDA-Ti showed better selectivity and a lower detection limit (0.2 fmol/μL). Moreover, 2422 unique phosphopeptides were identified from HeLa cell extracts with a high specificity (> 95%) enabled by DMSNs@PDA-Ti, better than those in previous reports

River Ecosystem Health Assessment Using a Combination Weighting Method: A Case Study of Beijing Section of Yongding River in China

(1) Background: River health assessment provides the foundation for sustainable river development and management. However, existing assessments have no uniform standards and methods. (2) Methods: The combination weighting method was proposed, drawing on the advantages of subjective and objective weighting methods. To comprehensively investigate the river health level, an index system based on 16 indices selected from river morphology, river water environment, riparian condition, and social services level was established. The method and framework were applied to the Beijing section of Yongding River in China. (3) Results: The comprehensive weights of river morphology, river water environment, riparian condition, and social services are 0.1614, 0.3170, 0.4459, and 0.0757, respectively. The river health comprehensive index of Yongding River is 3.805; the percentages of excellent, healthy, sub-healthy, unhealthy, and sick river segments are 0%, 11%, 69%, 20%, and 0%, respectively. (4) Conclusions: The results indicate that Yongding River is in a sub-healthy state, and the riparian condition is the key factor that affects the river ecosystem health. Health level exhibited a remarkable spatial variation, mainly influenced by anthropogenic activities, and effective measures are needed to minimize the impact in fragile ecological areas

Mechanism of Yifei Decoction Combined with MitoQ on Inhibition of TGFβ1/NOX4 and PDGF/ROCK Signal Pathway in Idiopathic Pulmonary Fibrosis

Background. Rho-related coiled helix forming protein kinase (Rho-ROCK) and another important fibrogenic factor-PDGF play a critical role in collagen deposition in rat lung tissue. Yifei decoction (YFT), a Chinese herbal decoction, has been used to treat idiopathic pulmonary fibrosis (IPF) in clinical practice and has produced positive outcomes; however, convincing evidence is currently lacking. The present study aimed to investigate the effects of YFT combined with MitoQ in rats with IPF and to explore the underlying mechanism. Methods. Rat IPF model was established by endotracheal injection of 5 mg/kg BleomycinA5 into the specific pathogen-free SD rats. MitoQ (6.5 μmol/kg once daily), YFT (10 ml/kg once daily), and MitoQ + YFT (6.5 μmol/kg + 10 ml/kg once daily) were used to treat the rat model for 4 weeks, respectively. The normal rats without IPF were used as the controls. After 4 weeks of drug treatment, lung histopathology was assessed. Immunohistochemistry was used to detect the expression of fibronectin and collagen IV in lung tissue. The expression of IL-6, IL-1β, TNF-α, GSH-Px, SOD, MDA, and hydroxyproline was determined by enzyme-linked immunosorbent assay. The expressions of TGFβ1, NOX4, PDGFR-β, and ROCK1 were determined using real-time quantitative PCR and Western blot. Results. After 4 weeks of drug treatment, comparison of the MitoQ + YFT group with the IPF group showed that lung injury scores, W/D, lung tissue hydroxyproline, fibronectin, collagen IV content, and IL-6, IL-1β, TNF-α, and MDA levels were significantly lower (P<0.05), as well as the expression of TGFβ1, NOX4, PDGFR-β, and ROCK1, but the activity of GSH-Px and SOD was higher (P<0.05). Conclusion. MitoQ combined with YFT can improve lung injury in rats with pulmonary fibrosis by reducing the secretion of proinflammatory cytokines and inhibiting TGFβ1/NOX4 and PDGF/ROCK signaling pathways. It may provide a new method for the treatment of pulmonary fibrosis

Dendritic Mesoporous Silica Nanoparticles with Abundant Ti⁴⁺ for Phosphopeptide Enrichment from Cancer Cells with 96% Specificity

Selective enrichment and sensitive detection of phosphopeptides are of great significance in many bioapplications. In this work, dendritic mesoporous silica nanoparticles modified with polydopamine and chelated Ti⁴⁺ (denoted DMSNs@PDA-Ti⁴⁺) were developed to improve the enrichment selectivity of phosphopeptides. The unique central-radial pore structures endowed DMSNs@PDA-Ti⁴⁺ with a high surface area (362 m² g^–1), a large pore volume (1.37 cm³ g^–1), and a high amount of chelated Ti⁴⁺ (75 μg mg^–1). Compared with conventional mesoporous silica-based materials with the same functionalization (denoted mSiO₂@PDA-Ti⁴⁺) and commercial TiO₂, DMSNs@PDA-Ti⁴⁺ showed better selectivity and a lower detection limit (0.2 fmol/μL). Moreover, 2422 unique phosphopeptides were identified from HeLa cell extracts with a high specificity (>95%) enabled by DMSNs@PDA-Ti⁴⁺, better than those in previous reports