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Monitoring Pb2+ contentin drinking water is an important measure to safeguard water safety for residents. To overcome drawbacks available electrochemical sensors, this work attempts to fabricate a boron-doped diamond (BDD) electrode for detecting Pb2+ in water. A systematic investigation was conducted on microstructural and electrochemical performances of BDD electrode. The results show that, diamond grains arrange well on BDD electrode surface. The electrode exhibits a high electrochemical active surface area and low charge transfer resistance, favorable to accelerate the stripping reaction process of Pb2+. BDD electrode has a low detection limit in optimized parameter set. Also, the BDD electrode has a good anti-interference ability. The designed BDD electrode is expected to be applicable for monitoring Pb2+ content in waters.

The oil-water and gas-water relative permeability curves are important reference data for the dynamic analysis and numerical simulation of oil and gas reservoir exploitation. Although the petroleum industry of China and other countries have formulated reference standards for the measuring methods of relative permeability of cores, they haven’t given the definite reference values of the core length, therefore we cannot know for sure whether different core length values are required in the measurement and whether the core length has an impact on the measurement results. In view of this gap, this paper conducted a research on the relative permeability of cores with different lengths. The core samples are artificial core with similar properties as the outcrop cores of the Halfaya Oilfield (Iraq), in our experiment, the oil-water and gas-water relative permeability curves of the sample cores were measured and the results suggest that, for the oil-water relative permeability curves, as the core length grows, the iso-permeability points move to the right, and they basically stabilize when the core length is greater than 20cm; as for gas-water relative permeability curves, in case of low-permeability cores, under constant injection pressure, as the core length grows, the iso-permeability points and the two-phase co-permeation areas present an obvious tendency of moving to the left, but when the core length is greater than 20cm, such tendency is not obvious, and the high-permeability cores do not have such characteristics. These results indicate that, the unsteady-state two-phase relative permeability measurement experiments obtained accurate results at a core length of about 20cm, which provided a reference for similar experiments in subsequent research.

Cell-based vaccine manufacturing is an important strategy for viral disease prevention. Cultivating cells in suspension could maximize the utility of large bioreactors for cost-effective and scaled up vaccine production, where adapting adherent cells to suspension culture is the bottleneck and key. Through whole transcriptome sequencing of suspension and adherent strains of BHK-21 and CHO-K1 cells followed by the identification of differentially expressed genes, mutational analysis, gene ontology, and pathway enrichment analysis, we identified four candidate genes, PABPC1, LARS, GLUL, PFN1, feasible for genetically modulating anchorage-dependent cells toward cell suspension culture, and experimentally validated the functionality of PABPC1 in both BHK-21 and CHO-K1 cells. Our study unveiled a novel role of PABPC1 that could potentially aid in the establishment of a cost-effective vaccine manufacturing platform relying on cell cultivation in suspension.

Replacing natural aggregate (NA) by recycled aggregate (RA) has contributed to the trend of sustainable development in civil construction. In this background, improvements in the mechanical properties of RAC and the scientific design of the mixture ratio are calling more concerns in recent years. This paper is a review of the recent research, including the following aspects: the mixture design of RAC; the improved mechanical properties of recycled concrete with steel fibers; the performance of the main components. In addition, the primary composition materials, properties, and calculation methods of the mixture ratio of RAC are summarized. The mechanical properties, durability and microscopic analysis of RAC are also discussed. The accurate calculation of mixture proportion can significantly facilitate the work of preparing a test mix of RAC. Through the mixture-ratio optimization and physical and chemical strengthening of RA, the mechanical properties of RAC can be improved to promote the wider application of this eco-friendly material.

Canine parvovirus (CPV) has been used in cancer control as a drug delivery vehicle or anti-tumor reagent due to its multiple natural advantages. However, potential host cell cycle arrest induced by virus infection may impose a big challenge to CPV associated cancer control as it could prevent host cancer cells from undergoing cell lysis and foster them regain viability once the virotherapy was ceased. To explore CPV-induced cell cycle arrest and the underlying mechanism toward improved virotherapeutic design, we focus on epidermal growth factor receptor (EGFR), a cellular receptor interacting with TfR that mediates CPV-host interactions, and alterations on its tyrosine phosphorylation sites in response to CPV infection. We found that CPV could trigger host G1/S cell cycle arrest via the EGFR (Y1086)/p27 and EGFR (Y1068)/STAT3/cyclin D1 axes, and EGFR inhibitor could not reverse this process. Our results contribute to our understandings on the mechanism of CPV-induced host cellular response and can be used in the onco-therapeutic design utilizing CPV by preventing host cancer cells from entering cell cycle arrest.

Cell culture-based vaccine technology is a flexible and convenient approach for vaccine production that requires adaptation of the vaccine strains to the new cells. Driven by the motivation to develop a broadly permissive cell line for infection with a wide range of viruses, we identified a set of the most relevant host receptors involved in viral attachment and entry. This identification was done through a review of different viral entry pathways and host cell lines, and in the context of the Baltimore classification of viruses. In addition, we indicated the potential technical problems and proposed some solutions regarding how to modify the host cell genome in order to meet industrial requirements for mass production of antiviral vaccines. Our work contributes to a finer understanding of the importance of breaking the host–virus recognition specificities for the possibility of creating a cell line feasible for the production of vaccines against a broad spectrum of viruses.

Powered by rapid technology developments, biomarkers become increasingly diverse, including those detected at genomic, transcriptomic, proteomic, metabolomic and cellular levels. While diverse sets of biomarkers have been utilized in breast cancer predisposition, diagnosis, prognosis, treatment and management, recent additions derived from lincRNA, circular RNA, circulating DNA together with its methylated and hydroxymethylated forms and immune signatures are likely to further transform clinical practice. Here, we take breast cancer as an example of heterogeneous diseases that require many informed decisions from treatment to care to review the huge variety of biomarkers. By assessing the advantages and limitations of modern biomarkers in diverse use scenarios, this article outlines the prospects and challenges of releasing complimentary advantages by augmentation of multiscale molecular biomarkers.

Variable stiffness is the focus and difficulty in the research of soft robotics technology, and the variable stiffness of the multi-degree-of-freedom (MDOF) soft structure is more challenging. Inspired by the transverse and longitudinal muscle structure of octopus arms, using parallel and spiral pneumatic artificial muscles (PAMs) to imitate the transverse and longitudinal muscle structure respectively, and then the MDOF movement and variable stiffness function of a soft finger can be realized by the mutual coupling of PAMs. Based on the rigid-flexible-soft design strategy, a rigid frame is embedded in the spiral PAM, which improves the regularity and stability of the finger module movement, and provides a good hardware foundation for simplifying theoretical model. A dexterous gripper is designed based on the MDOF variable stiffness finger module, which has four grasping modes, such as non-parallel bending inward, non-parallel bending outward, parallel bending inward, and parallel bending outward. Then the kinematics model of the soft finger is established based on the assumption of constant curvature and its workspace is solved. The MDOF variable stiffness performance of the finger module is experimentally analyzed, and a multi-target grasping experiment is carried out. It is proved that the dexterous gripper has good adaptability and flexibility, and experimental results show that the load capacity of the soft gripper can be improved by this variable stiffness method. This research provides a theoretical and technical reference for the development of MODF soft structures with variable stiffness.

The tortuosity of corneal nerve fibers is correlated with a number of diseases such as diabetic neuropathy. The assessment of corneal nerve tortuosity level in in vivo confocal microscopy (IVCM) images can inform the detection of early diseases and further complications. With the aim to assess the corneal nerve tortuosity accurately as well as to extract knowledge meaningful to ophthalmologists, this chapter proposes a fuzzy pattern tree-based approach for the automated grading of corneal nerves’ tortuosity based on IVCM images. The proposed method starts with the deep learning-based image segmentation of corneal nerves and then extracts several morphological tortuosity measurements as features for further processing. Finally, the fuzzy pattern trees are constructed based on the extracted features for the tortuosity grading. Experimental results on a public corneal nerve data set demonstrate the effectiveness of fuzzy pattern tree in IVCM image tortuosity assessment.

With the high pervasiveness of viral diseases, the battle against viruses has never ceased. Here we discuss five cellular processes, namely “autophagy”, “programmed cell death”, “immune response”, “cell cycle alteration”, and “lipid metabolic reprogramming”, that considerably guide viral replication after host infection in an orchestrated manner. On viral infection, “autophagy” and “programmed cell death” are two dynamically synchronized cell survival programs; “immune response” is a cell defense program typically suppressed by viruses; “cell cycle alteration” and “lipid metabolic reprogramming” are two altered cell housekeeping programs tunable in both directions. We emphasize on their functionalities in modulating viral replication, strategies viruses have evolved to tune these processes for their benefit, and how these processes orchestrate and govern cell fate upon viral infection. Understanding how viruses hijack host networks has both academic and industrial values in providing insights toward therapeutic strategy design for viral disease control, offering useful information in applications that aim to use viral vectors to improve human health such as gene therapy, and providing guidelines to maximize viral particle yield for improved vaccine production at a reduced cost.

Establishing a stable, reliable and sensitive assay for the direct analysis in trace serum is of significance for the medical diagnosis and disease monitoring. We develop a MnO2 shell-isolated SERS nanoprobe (Au-Mpy-Au-MnO2, AMAM) for the quantitative detection of alkaline phosphatase (ALP) in trace serum. Due to the physical isolation of MnO2 shell, AMAM is equipped with high stability, rarely happening the accidental aggregation. Particularly, the SERS signal is regulated by the etching of MnO2 shell, requiring not to change the local electromagnetic field or the molecular structure of Raman reporter (4-mercaptopyridine (Mpy)). Designating MnO2 shell as the Raman reference and the ratio of IMpy/IMnO2 as the response signal, AMAM system can obviously eliminate the experimental interference and achieve highly reliable SERS quantification for ALP. This ratiometric SERS system exhibits good reproducibility, high stability and sensitivity for the ALP analysis. AMAM system is able to perform the colorimetric and SERS dual-readout detection, which displays a wide linear dynamic range (0.1–70 U/L) for ALP with a detection limit of 0.079 U/L. Additionally, integrating with in-capillary SERS technique, our proposed nanoprobe is also applicable of direct SERS analysis in trace undiluted human serum (2 μL).

Because of the complicated modification process, easy aggregation and low reproducibility, conventional Au-based SERS nanoprobes encountered a great bottleneck in clinical assay. We develop an alkyne functionalized graphene-isolated-Au-nanocrystal (AGIAN) SERS nanoprobe for the ratiometric analysis of alkaline phosphatase (ALP) in Raman-silent region with acetonitrile as the internal standard. Through a simple ultrasound treatment, the Raman reporter can be strongly bond on the graphene surface to prepare the AGIAN SERS nanoprobe within several minutes. Owing to the excellent physical isolation of graphene, the AGIAN nanoprobe possesses admirable stability, keeping off the irreversible metal aggregation. Moreover, with the intensity ratio between the Raman molecule (alkyne reporter) and the internal standard (acetonitrile solvent) as the signal, this nanoprobe is capable of reliable SERS detection of the ALP, effectively avoiding the optical fluctuations resulted from the external interferences. Particularly, the characterized peaks from the self-synthesized alkyne molecule and acetonitrile solvent are both strong and separated in Raman-silent region, suffering no signal overlapping with the biosystem and leading to reliable analytical results. Therefore, along with simple modification, high stability and accuracy, our SERS system provides a novel solution for the important appeal of SERS analysis in the clinical application.

In this Letter, we propose a compact multimode fiber endoscope which employs wavefront shaping with a digital micromirror device (DMD). An automated single calibration step allows us to correct for optical misalignment, and the method achieves accurate focusing at various depths in the sample through rapid switching of holographic patterns by the DMD. The speed of calibration is one or two orders of magnitude faster than existing methods. The method, single calibration multimode fiber imaging (SCMFI), is compared with existing methods, and its performance is validated. We show a near diffraction limited focusing capability at imaging depths up to 110 µm with near constant lateral resolutions of 1.4 µm. Finally, we demonstrate the method for the imaging of small fluorescent beads embedded in a 3D matrix. The results indicate excellent power penetration and focusing performance. Combined with the high speed of SCMFI, this paves the way for volumetric tissue endoscopy at depth.

The property of the multimode fiber (MMF) to remain minimally invasive when performing high-resolution observations, makes MMF imaging of particular interest in many related fields recently, especially in bioendoscopic imaging. Imaging through point scanning is the most common method of MMF imaging now, which means modulating a scanning focal spot on the end face of fiber by controlling modes in the fiber. However, due to mode interference, there is always a background speckle around the focal spot formed, which affects imaging quality seriously. Increasing controllable modes number can effectively suppress the effects of the background speckle, but it is limited by the number of controllable elements (the elements number of wavefront shaping devices). Here, we propose a new, to the best of our knowledge, method to increase the contrast-to-noise ratio (CNR) of MMF imaging without increasing the number of controllable modes. Wavelength modulation is introduced to suppress the background. The background speckles turn to be uncorrelated, whereas the signal patterns turn to be strongly correlated and can be added when 20 different wavelengths of light form a focal spot at the same position at the distal end of MMF, respectively. Thus, a four-fold enhancement can be gained in CNR at a 200 µm field-of-view (FOV) by suppressing background speckles.