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The stoppage of a mobile platform is generally scheduled to feed parts for machines on production lines, such as fenced industrial robotic manipulators. A non-stop mobile robotic part feeding system can contribute to production efficiency and flexibility but contains several challenging tasks. For example, the industrial robotic manipulator needs to perceive the positions of the mobile robot accurately and robustly before grasping the supplies when the mobile robot moves around. Thus, based on the relative distance between the two robots, an interaction mode of the integrated robotic system consisting of a fixed robotic manipulator and a mobile robot is developed for robotic interaction. In order to accurately and robustly perceive the positions of a mobile robot, two different positioning approaches for the robotic manipulator positioning mobile robot in an indoor environment are utilised. One approach is ultrasonic sensors fused with inertia measurement units (IMU) by extended Kalman filter (EKF). Furthermore, an outlier rejection mechanism is implemented to escape outliers from ultrasonic measurement. Another positioning approach is achieved by detecting an ArUco marker with visual sensor. Lastly, a positioning switching strategy according to the visual sensor state allows the robotic manipulator to reposition the mobile robot seamlessly. According to the static experiments, EKF-based positioning approach fusing IMU with ultrasonic sensor can export high-accuracy (the root mean square error is 0.04 m) and high-precision (the standard deviation is 0.0033 m) in positioning while keeping a high update frequency of 181.9 HZ in static positioning. Evaluations through dynamic experiments demonstrate that the proposed positioning system can suppress the positioning drifts over time in comparison with wheel encoder-based positioning method. The two-stage repositioning strategy can support the robotic manipulator to identify the positions of the mobile robot robustly, even in the case when the visual sensor is occluded.

A supramolecular nanoprodrug (DOX@GP5⊃Pro-NFA) was constructed based on the host–guest complexation of a chloride channel blocker prodrug (Pro-NFA) and glycosylated pillar[5]arenes (GP5), which could target chemoresistance cancer therapy.

Head and neck squamous cell carcinoma (HNSCC), as the most common type (90%) of head and neck cancer, includes various epithelial malignancies that arise in the nasal cavity, oral cavity, pharynx, and larynx. In 2020, approximately 878 ‍ 000 new cases and 444 000 deaths linked to HNSCC occurred worldwide (Sung et al., 2021). Due to the associated frequent recurrence and metastasis, HNSCC patients have poor prognosis with a five-year survival rate of 40%-50% (Jou and Hess, 2017). Therefore, novel prognostic biomarkers need to be developed to identify high-risk HNSCC patients and improve their disease outcomes.

A supramolecular nano-delivery system GP5⊃Pro-ANI based on the host-guest complex of glycosylated pillar[5]arene (GP5) and an amide linked fluorescent PARP inhibitor (4-amino-1,8-naphthimide, ANI) was constructed. The PARP inhibitor ANI, capable of inhibiting the ability of DNA damage repair, was modified into an AIE prodrug (Pro-ANI), which allows for the visualization of real-time cancer cellular drug uptake tracing and selective drug release.

We show the existence of global-in-time solutions to an initial-boundary value problem in one space dimension of a phase-field model on the martensitic phase transformations, which consists of the equations of degenerate and a nondegenerate nonlinear parabolic equation of second order.

Objective Fetoscopic laser surgery (FLS) is currently the standard treatment for twin to twin transfusion syndrome (TTTS). This study aims to improve the perinatal outcomes of TTTS patients by analyzing the risk factors associated with preterm delivery after FLS for TTTS. Methods A prospective cohort study was conducted in 97 cases of patients with TTTS who underwent FLS at the Third Affiliated Hospital of Zhengzhou University from May 2018 to December 2020. A multivariate logistic regression model was used to determine the risk factors associated with preterm delivery. Finally, ROC curve was utilized to analyze the diagnostic value of related risk factors. Results A total of 90 TTTS patients were included in the study. There were 37 cases in group A and 53 cases in group B. Through multivariate logistic regression model analysis, three risk factors related to the gestational age of childbirth P P=0.024), placental abruption (OR, 17.6; P=0.018). ROC curve analysis suggested that the AUC of the combined diagnosis of the three factors was 0.799 (P

Composite materials are widely used in industry due to their light weight and specific performance. Currently, composite manufacturing mainly relies on manual labour and individual skills, especially in transport and lay-up processes, which are time consuming and prone to errors. As part of a preliminary investigation into the feasibility of deploying autonomous robotics for composite manufacturing, this paper presents a case study that investigates a cooperative mobile robot and manipulator system (Co-MRMS) for material transport and composite lay-up, which mainly comprises a mobile robot, a fixed-base manipulator and a machine vision sub-system. In the proposed system, marker-based and Fourier transform-based machine vision approaches are used to achieve high accuracy capability in localisation and fibre orientation detection respectively. Moreover, a particle-based approach is adopted to model material deformation during manipulation within robotic simulations. As a case study, a vacuum suction-based end-effector model is developed to deal with sagging effects and to quickly evaluate different gripper designs, comprising of an array of multiple suction cups. Comprehensive simulations and physical experiments, conducted with a 6-DOF serial manipulator and a two-wheeled differential drive mobile robot, demonstrate the efficient interaction and high performance of the Co-MRMS for autonomous material transportation, material localisation, fibre orientation detection and grasping of deformable material. Additionally, the experimental results verify that the presented machine vision approach achieves high accuracy in localisation (the root mean square error is 4.04 mm) and fibre orientation detection (the root mean square error is 1.84∘) and enables dealing with uncertainties such as the shape and size of fibre plies.

Composite materials are widely used because of their light weight and high strength properties. They are typically made up of multi-directional layers of high strength fibres, connected by a resin. The manufacturing of composite parts is complex, time-consuming and prone to errors. This work investigates the use of robotics in the field of composite material manufacturing, which has not been well investigated to date (particularly in simulation). Effective autonomous material transportation, accurate localization and limited material deformation during robotic grasping are required for optimum placement and lay-up. In this paper, a simulation of a proposed cooperative robotic system, which integrates an autonomous mobile robot with a fixed-base manipulator, is presented. An approach based on machine vision is adopted to accurately track the position and orientation of the fibre plies. A simulation platform with a built-in physics engine is used to simulate material deformation under gravity and external forces. This allows realistic simulation of robotic manipulation for raw materials. The results demonstrate promising features of the proposed system. A root mean square error of 9.00 mm for the estimation of the raw material position and 0.05 degrees for the fibre orientation detection encourages further research for developing the proposed robotic manufacturing system.

In this paper, p-type thermoelectric material Te–Se solid solutions have been successfully prepared by the high-pressure technique. The thermal conductivity of Te was depressed sharply by Se alloying. An extremely low thermal conductivity ∼0.27 W m−1 K−1 was obtained for Te alloyed with 15 mol% Se, which near the theoretical minimum, κ min . The bipolar diffusion effect of Te was suppressed by Se alloying due to the increased band gap, which lead to enhanced Seebeck coefficient and depressed bipolar diffusion thermal conductivity under high temperature. The maximum figure of merit, ZT of 0.37 at 480 K was obtained for Te alloyed with 5 mol% Se, which is about twice higher than that of pristine Te.

Carbon dots (CDs) were synthesized by refluxing glucose, as efficient fluorescence probes, which show convenient and sensitive detection of norfloxacin (NOR) over a wide concentration range. It is worth noting that because of the hydrogen bond interactions between the CDs and NOR, the fluorescence intensity of CDs was remarkably enhanced in the presence of NOR, which indicates that CDs are capable of rapid, stable and sensitive determination of NOR. Compared with high-performance liquid chromatography, the fluorescence enhancement method is considerably simpler and faster, and will pave a new way for the determination of NOR.

Recently, it was found that element semiconductor tellurium (Te) behaved a high thermoelectric (TE) performance. Further enhancement of its TE performance was expected in decreasing phonon thermal conductivity. In this paper, element semiconductor Te doped with arsenic (As) and alloyed with selenium (Se) was prepared by one-step high-pressure method. Trace amounts of As doping could increase the carrier concentration of Te effectively and thereby optimize its power factor. The phonon thermal conductivity of Te was depressed sharply, due to the effect of high-pressure compression (introducing dislocations, lattice curvatures and nanograins) and Se alloying (introducing point defects and crystal dislocation). The beneficial effect of As doping on the power factor, high-pressure compression and Se alloying on thermal conductivity led to a peak ZT of 0.81 at 540 K for Te doped with 0.5 mol% As and alloyed with 10 mol% Se.

Besides high thermoelectric (TE) performance, simple chemical compositions and facile synthesis methods are attractive for practical fabrication and applications of TE materials due to their effective rates of synthesis and higher stabilities. Element semiconductor Tellurium (Te) is one potential middle temperature TE material and has attracted wide interest in material science. In this study, we report that a high thermoelectric performance ZT ~ 0.88@600 K for polycrystalline Te with slight Antimony (Sb) doping was facile synthesized by one-step high pressure technique. Our experimental results reveal that the carrier concentration of high pressure synthesized Te is more sensitive to dopants compared with the samples obtained by the conventional preparation method. We observed large amount of nanograins, second nano-phase and crystal defects in the high pressure synthetic samples, which can significantly weaken the phonon thermal conductivity, leading to a high TE performance in Te samples. This work indicates that high pressure method provides an alternative direction for designing TE materials with simple composition.

Recently, it was found that element semiconductor tellurium (Te) has a high thermoelectric performance. However, it needs to be doped with high-toxic arsenic (As) to tune the carrier concentration of Te. In this paper, low-toxic bismuth (Bi) was employed as dopant to optimize the thermoelectric performance of Te combining with a high-pressure synthesis method. The effect of substituting Bi on the electrical transport and thermal transport properties of Te has been investigated. The results show that the solubility limit of Bi in Te is about 0.1 mol%. However, the trace amounts of Bi doping can tune the carrier concentration of Te effectively and thereby optimize its power factor. The thermal conductivity of non-doped Te prepared by high pressure is much lower than that of the sample prepared at ambient pressure. And Bi doping can further decrease the value due to the phonons scattered by the heavy impurity atom. An enhanced figure of merit ZT ~ 0.72 was obtained at 517 K, which is about four times that of non-doped Te and is comparable to the state-of-the-art thermoelectric alloys with more complex composition such as Bi2Te3 and PbTe.

N-type thermoelectric materials PbTe doped with iodine (PbTe 1−x I x , x = 0.0001, 0.0003, 0.0007 and 0.001) were synthesized by high pressure and high temperature method (HPHT). Thermoelectric properties of PbTe 1−x I x are investigated in the range of 300–600 K. The carrier concentration of PbTe prepared by HPHT is more sensitive to I content compared to that of the PbTe 1−x I x sample prepared by other methods. The resistivities and the absolute values of Seebeck coefficients for PbTe 1−x I x increase while the thermal conductivities decrease with increasing temperature. A large power factor of 39.1 μW/(cmK 2 ) at room temperature is obtained with the carrier concentration of 9.7 × 10 18 cm −3 , which is much higher than that of Sb and Bi doped PbTe with the same synthesizing conditions. The high power factor is attributed to the high Hall mobility and large effective mass. The maximum figure-of-merit, ∼0.71 @ 600 K, is obtained for the samples with the carrier concentration of 9.7 × 10 18 cm −3 .

This paper provides a comprehensive review of the development of Collaborative Mobile Industrial Manipulator (CMIM), which is currently in high demand. Such a review is necessary to have an overall understanding about CMIM advanced technology. This is the first review to combine the system architecture and application which is necessary in order to gain a full understanding of the system. The classical framework of CMIM is firstly discussed, including hardware and software. Subsystems that are typically involved in hardware such as mobile platform, manipulator, end-effector and sensors are presented. With regards to software, planner, controller, perception, interaction and so on are also descripted. Following this, the common applications (logistics, manufacturing and assembly) in industry are surveyed. Finally, the trends are predicted and issues are indicated as references for CMIM researchers. Specifically, more research is needed in the areas of interaction, fully autonomous control, coordination and standards. Besides, experiments in real environment would be performed more and novel collaborative robotic systems would be proposed in future. Additionally, some advanced technology in other areas would also be applied into the system. In all, the system would become more intelligent, collaborative and autonomous.

Because of the unique layered structure, black phosphorus (BP) provides a possibility of relatively independent control in electrical and thermal conductivity for thermoelectrical applications. It is therefore of great interest to realize high-performance BP-based thermoelectrics as flexible non-toxic and ultralight devices in spite of the low energy conversion efficiency and structural instability of the bulk BP. In this work, we systematically study the thermoelectric properties for the two-dimensional BP from mono-layer up to quad-layer by first-principles calculations and Boltzmann transport theory. It can be concluded from the calculations that the thermoelectric performance of BP nanosheets can be effectively optimized by tuning the layer thickness. We reveal that the maximum ZT values at 300 and 500 K can reach up to 0.45 and 0.90 in p-type bi-layer BP along armchair direction, respectively, around 5 times higher than that of the bulk at room temperature. The high performance in bi-layer BP is mainly attributed to its highly anisotropic and degenerate carrier pockets. Accordingly, we further propose that the formation of BP/h-BN heterostructure can enhance ZT up to 1.2 at 500 K, which facilitates the real application of thin BP for flexible and eco-friendly thermoelectrics.

While carbon supported platinum (Pt) catalyst is the most effective and widely used cathode catalyst for oxygen reduction reaction (ORR) in proton exchange membrane fuel cells, the preparation of active and stable Pt catalysts remains challenging. In this work, we report a room temperature electron reduction method for the synthesis of a highly active and stable carbon supported Pt (111) catalyst under peptide assistance (Pt (111)-P/C). Such prepared catalyst shows surface sites featuring predominately (111) facets with particle size around 2 nm. In comparison with commercial Pt/C catalyst prepared by conventional methods, the mass activity and specific activity of the Pt (111)-P/C catalyst for ORR are shown to increase by a factor of ~2. A 10,000-cycle durability test of the Pt (111)-P/C catalyst has also showed a significantly enhanced stability over the commercial Pt/C catalyst.

In this paper, we first introduce the first-order formalism with the self-dual structure of the motion equations, also called the Bogomol’nyi and Prasad–Sommerfield (BPS) equations. We observe that BPS equations arising in the generalized Maxwell–Higgs model under specific circumstances can be transformed into a vortices–antivortices equation, which is a nonlinear elliptic equation with the exponential functions. For the vortices–antivortices equation in two space dimensions, we prove the existence of topological solutions by a monotone iteration method. Finally, we give the asymptotic estimates of solutions obtained at infinity.

Ras-related nuclear protein (Ran) GTPase plays an important role in nucleo-cytoplasmic transportation of proteins and RNA, mitotic spindle assembly, microtubule assembly and nuclear envelope (NE) assembly. We previously identified the full-length cDNAs and a DNA of DlRan3A from longan (Dimocarpus longan Lour.) somatic embryos and demonstrated its possible roles in cell activities during longan somatic embryogenesis (SE). However, thus far little is known of how Ran functions in the signaling pathways in plant embryos in response to changing environmental stimuli. To discover more biological roles of DlRan3A, we observed DlRan3A located in the nucleus and detected abundant accumulation of DlRan3As in globular and cotyledon embryos during longan SE, which suggested its involvement in auxin signal pathways in longan early SE. The transcript level of the DlRan3A gene were also determined in longan embryogenic callus (EC) in response to different levels of exogenous phytohormones (indoleacetic acid (IAA), gibberellin A3 (GA3), salicylic acid (SA), methyl jasmonate (MeJA), and ethephon (Eth)), salt, sucrose, prolonged culturing period and light quality treatments. IAA (1mg/L), GA3 (12 mg/L), SA (75 μm), MeJA (50 and 100 μm), and Eth (50mg/L) modulate expression of DlRan3A to 1.3-1.4 folds, and the expression of DlRan3A was significantly affected by light quality, significantly induced to 2-fold by salt (10 g/L), 2.7-fold by sucrose (90 g/L) and was completely suppressed by prolonged cultivation (>40 days). Deletion analysis suggested that both activation and repression regulatory elements co-exist in the DlRan3A promoter sequence and that the key cis-acting elements included ones in response to auxin, SA, MeJA, and stress. Promoter activities were induced to the highest level by IAA followed by SA, GA3 and MeJA, while suppressed by ABA and Eth. Together, these results showed DlRan3A close involvement in phytohormones, light, and abiotic stress responsiveness during longan SE.

We describe the preparation of carbon dots (CDs) from glucose that possess high stability, a quantum yield of 0.32, and low toxicity (according to an MTT assay). They were used, in combination with the fluorogenic zinc(II) probe quercetin to establish a fluorescence resonance energy transfer (FRET) system for the determination of Zn(II). The CDs are acting as the donor, and the quercetin-Zn(II) complex as the acceptor. This is possible because of the strong overlap between the fluorescence spectrum of CDs and the absorption spectrum of the complex. The method enables Zn(II) to be determined in the 2 to 100 μM concentration range, with a 2 μM detection limit. The method was applied to image the distribution of Zn(II) ions in HeLa cells.

Species of Ganoderma are used in traditional medicines. An improved random amplified polymorphic DNA (RAPD) analysis, where the RAMP time is prolonged, has been used to characterize the genetic variation in some well known species of Ganoderma. The DNA materials were collected from ten Ganoderma strains, amplified with randomly selected 24 RAPD primers and evaluated by agarose gel electrophoresis. A cluster dendrogram was constructed for genetic analysis on the basis of amplification results. The improved RAPD amplified DNA with consistent and clear banding patterns. A total of 316 bands were found with 93% polymorphism. There was a significant genetic distance between the different strains of Ganoderma, with an index of similarity coefficient in the range of 0.52–0.74. The inter-simple sequence repeat (ISSR) analysis of the Ganoderma DNA samples showed similar trend results to the RAPD analysis with 0.49–0.81 similarity coefficients. This study reports the high level of genetic differences between different species or strains of a single species of Ganoderma and confirms the significance of the improved RAPD method in genetic characterization of organisms. Therefore, the improved RAPD combined with ISSR techniques might be used for the genetic characterization of organisms.

A carbon dots/tyrosinase (CDs/TYR) hybrid as a low-cost fluorescent probe for the detection of dopamine exhibits high sensitivity, stability, and precision. The detection limit of dopamine is as low as 6.0 × 10−8 mol L−1, and the wide detection range is from 1.318 × 10−4 mol L−1 to 2.06 × 10−7 mol L−1. This kind of fluorescent probe did not need enzyme immobilization and modification, and the experiment results could be revealed as soon as the probe–sample incubation was completed. More importantly, these test results are comparable to that of the present clinical fluorescence detection and high-performance liquid chromatography (HPLC), and the results show that the three methods agreed well with each other.

A step-by-step room temperature electron reduction has been developed in this work to prepare silver nanoparticle aggregates on anodic aluminium oxide (AAO) substrate. No chemical reducing agent is needed. The aggregates are formed by silver nanoparticles with a particle size of about 3 nm. The colour of the silver nanoparticle aggregates can be adjusted from yellow (with small Ag loading) to dark (with high Ag loading). Especially, the colour of these aggregates depends on the size of the Ag nanoparticle aggregate, rather than on the size of the single Ag nanoparticles. The silver aggregate/AAO composites show an outstanding surface plasmon resonance (SERS) characteristic. The Raman enhancement factor reaches as high as 1.054 × 107. The silver nanoparticle aggregates can be dispersed as Ag nanoparticles within a liquid solution with the removal of the substrate under the assistance of ultrasonic dispersion. The silver nanoparticle aggregates obtained by this step-by-step electron reduction provide a convenient and sustainable means for the storage of metal nanoparticles.

We have studied the interaction between cefuroxime sodium (CXS) and papain at different temperatures by a fluorescence method, and confirmed that the mechanism of fluorescence quenching of CXS to papain is mainly static quenching. We also determined the binding constant K. Based on the thermodynamic functions at different temperatures, the results show that the major forces between CXS and papain are van der Waals’ forces and H bond. According to the Forster non-radiation energy transfer mechanism, we determined the binding distance between CXS and papain, and studied the confirmation effect of CXS to papain by synchronous fluorescence and UV–Vis spectroscopy. Molecular simulations show that the binding types of CXS and papain are van der Waals’ forces, hydrophobic interaction, and H-bond.

microRNA167 regulates vegetative and reproductive growth by controlling expression patterns of auxin response factors 6 and 8 (ARF6/8) in plants. However, their mutual regulatory roles during plant embryo development are still unknown. Here, we first identified miR167 family members, isolated the primary miR167 and its promoter, predicted endogenous target mimics (eTMs), identified miR167 targets, and analyzed their accumulation in Dimocarpus longan (longan). Four variants of dlo-miR167a and one dlo-miR167f were identified; their accumulation at the cotyledonary embryo stage suggests they may be required for cotyledon-shaped embryo morphogenesis in longan. We then isolated the miR167 precursor, primary transcript, and promoter. The promoter contained cis-acting elements responsive to stimuli such as light, fungal elicitors, heat, low temperature, drought, methyl jasmonate, salicylic acid, gibberellic acid, and circadian control. Two eTM homologs of a phosphatidylinositol 3- and 4-kinase family protein containing a FAT domain and an unknown protein were predicted for miR167. miR167 mediates transcript degradation in longan somatic embryos for DlARF8 but not cleaves for DlARF6. Moreover, both the eTMs were barely detectable in incomplete compact pro-embryogenic cultures and torpedo-shaped embryos, but reached peaks at globular embryos, which was largely reciprocal to that of their corresponding miR167, indicating a potential role in the negative control of miR167 expression; increased DlARF6 is required for somatic embryo development; miR167a/DlARF8 pair is essential to globular embryo formation and subsequent conversion to cotyledonary embryos. In addition, eTM-miR167-ARF6-8 signal transduction was found to play a conserved role in root development of the longan cultivar ‘Sijimi.’ We conclude that eTM down-regulates miR167 via cleavage of DlARF8 mRNAs in longan somatic embryo development, especially during late developmental stages.

The interaction between two 4th generation of new cephalosporin drugs and papain was studied through spectroscopy method at different temperatures. Their dissociation constants were calculated by using theoretical formula of fluorescence quenching and fluorescence enhancement, respectively, and their corresponding thermodynamic functions, dipole-dipole non-radiative energy-transfer-efficiency and the action distances of acceptor-substrate etc. were calculated further. Analysis reveals that, the quenching on papain by cefpirome and cefepime is basically due to the dipole-dipole non-radiation energy-transfer and certain dynamic collision between donor and acceptor, the interaction between drug and papain is mainly hydrophobic which may provide useful information for pharmacological and metabolic study on papain. In this paper fluorescence quenching is regarded as negative fluorescence enhancement, and two kinds of theoretical formula of fluorescence quenching and fluorescence enhancement were used to calculate the experimental data of fluorescence quenching of a same batch, and very close results were obtained but with certain difference. The results not only display the equivalence of the two theoretical equations when treating acceptor-substrate action, but also show that the thermodynamic data based on the theoretical formula of fluorescence enhancement (4), which is deduced by us, are more reasonable. So we suggest that even in the process of studying the fluorescence quenching between receptor-substrate, using the theoretical formula of fluorescence enhancement (4) can get more reliable results.

The action of the three kinds of new third generation cephalosporin-class drugs, cefepime hydrochroride, cefpiramide and ceftizoxime with HSA and BSA was studied at different temperatures through the fluorescence method. First, the binding constants were calculated by using fluorescence quenching and enhancement theoretical equations. Their thermodynamic functions were also calculated. Because the KA corresponding to the different theoretical equations are not completely the same, the thermodynamic parameters calculated are also different. In this paper, the differences among these thermodynamic data obtained from the different theoretical equations were analyzed and the results show that the thermodynamic data deduced from fluorescence enhancement are more reasonable. Thus, we propose that even when the fluorescence quenching action of the acceptorsubstrate is studied, more realistic data can be obtained by using the fluorescence enhancement equation.