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Protein folding is important for protein homeostasis/proteostasis in the human body. We have established the ability to manipulate protein unfolding/refolding for β-lactoglobulin using the induced mechanical energy in the thin film microfluidic vortex fluidic device (VFD) with monitoring as such using an aggregation-induced emission luminogen (AIEgen), TPE-MI. When denaturant (guanidine hydrochloride) is present with β-lactoglobulin, the VFD accelerates the denaturation reaction in a controlled way. Conversely, rapid renaturation of the unfolded protein occurs in the VFD in the absence of the denaturant. The novel TPE-MI reacts with exposed cysteine thiol when the protein unfolds, as established with an increase in fluorescence intensity. TPE-MI provides an easy and accurate way to monitor the protein folding, with comparable results established using conventional circular dichroism. The controlled VFD-mediated protein folding coupled with in situ bioprobe AIEgen monitoring is a viable methodology for studying the denaturing of proteins.

Lipid droplets (LDs) are evolutionarily conserved organelles involved in energy homeostasis and versatile intracellular processes in different cell types. Their importance is ubiquitous, ranges from utilization as the biofunctional components to third-generation biofuel production from microalgae, while morphology and functional perturbations could also relate to the multiple diseases in higher mammals. Biosynthesis of lipids can be triggered by multiple factors related to organismal physiology and the surrounding environment. An early prediction of this might help take necessary actions toward desired outcomes. In vivo visualization of LDs can give molecular insight into regulatory mechanisms and the underlying connections with other cellular structures. Traditional bioprobes for LDs detection often suffer from different dye-specific limitations such as aggregation-caused quenching and self-decomposition phenomena that hinder the research advancement. The emergence of lipid-specific nanoprobes with aggregation-induced emission (AIE) attributes in recent years is promising in remunerative characteristics with defined bioimaging properties. By utilizing the easy synthetic techniques and exploiting the unique physical features of these molecules, highly selective, stable, biocompatible and facile fluorescent probes could be fabricated for lipid detection. This chapter will provide up-to-date insight into the recent advances in lipid-specific AIE-based probes to enhance the opportunities for basic research related to the distinct roles of LDs in living organisms.

The design and fabrication of preforms for advanced composites have gained considerable attention in light of recently developed textile preforming techniques. It is within this realm of preforming technology that a full advantage of the knowledge to a process-structure-property relationship of three-dimensional (3D) braided composites may be realized. The fabrication history of these preforms directly determines composite microstructures and resulting mechanical properties. This chapter mainly reports the history of development, architecture, and processing techniques of 3D four-step braiding preforms and composite materials. The modeling strategy of three repeat unit cells (inner, surface, and corner repeat unit cell (RUC)) representing the entire braiding structure is presented along with corresponding structure characterization and mechanical properties of RUCs. Finally, the static, dynamic, and fatigue behaviors of 3D four-step composites under three-point bending, impact loading, and cyclic loading are reported.

Fluorescence imaging in the near-infrared II (NIR-II, 1000–1700 nm) region opens up new avenues for biological systems due to suppressed scattering and low autofluorescence at longer-wavelength photons. Nonetheless, the development of organic NIR-II fluorophores is still limited mainly due to the shortage of efficient molecular design strategy. Herein, we propose an approach of designing Janus NIR-II fluorophores by introducing electronic donors with distinct properties into one molecule. As a proof-of-concept, fluorescent dye 2 TT-m, oC6B with both twisted and planar electronic donors displayed balanced absorption and emission which were absent in its parent compound. The key design strategy for Janus molecule is that it combines the merits of intense absorption from planar architecture and high fluorescence quantum yield from twisted motif. The resulting 2 TT-m, oC6B nanoparticles exhibit a high molar absorptivity of 1.12 ⨯104 M−1 cm−1 at 808 nm and a NIR-II quantum yield of 3.7%, displaying a typical aggregation-induced emission (AIE) attribute. The highly bright and stable 2 TT-m, oC6B nanoparticles assured NIR-II image-guided cancer surgery to resect submillimeter tumor nodules. The present study may inspire further development of molecular design philosophy for highly bright NIR-II fluorophores for biomedical applications., Graphical abstract Image 1

The current research aimed to fabricate an alginate-hyperbranched polymer (HBP) complex, using a vortex fluidic device (VFD), to control the physicochemical, structural, and mechanical properties of alginate hydrogel; thus, providing a dominant biomaterial system for different biomedical applications. Samples were prepared by mixing alginate (6%w/w) with HBP (0.85 μM) before cross-linking with Ca2+ (100 mM). Magnet stirrer (600 rpm) and VFD (6000 rpm) were used to prepare experimental samples, and alginate was used as control. Comprehensive evaluations of bulk and surface morphology, microstructural analysis, swelling kinetics, mechanical characteristics, cytotoxicity, and formation of hydrogen bonds were conducted. The findings from this study revealed that the addition of HBP to alginate structure led to a higher swelling capability (86%), increased diffusion coefficient (66-fold), and enhanced failure mechanical properties (160% and 20% increases for failure stress and elongation at break, respectively) than control. Traditional mixing affected the surface morphology, while the bulk structure remained unchanged. Moreover, the rate of degradation was not significantly different between alginate and alginate-HBP samples. When VFD was incorporated, a higher swelling ratio (30%) was observed than the control sample and the coefficient of diffusion increased (34-fold). The associated degradation rate increased 30-fold, and the failure stress and elongation at break were increased 310% and 83%, respectively, compared to the control sample. The micromixing of alginate with HBP under high shear stress using a VFD created a micro-hybrid composite formed by alginate microparticles embedded in an alginate sheet.

Microplastics can potentially be released in our daily activities, such as via our showers, as our clothes are made of plastic fibres, and/or cotton fibres. The challenge is how to characterise these microplastics in shower debris. Herewith we employ Raman imaging to directly visualise the microplastics collected from shower wastewater. Raman can map an image from the scanning array that contains a matrix of thousands of spectra, featuring a considerably higher signal-noise ratio than that from a single spectrum. The increased signal-noise ratio reduces the complexity of sample preparation. Consequently, after the shower debris was sampled and washed, Raman imaging allowed us to distinguish the microplastic fibres from the background including cotton fibres and dirt aggregates. Interestingly, by adjusting the laser power intensity, the scanning process enabled simultaneous in-situ bleaching of the colorants formulated in the textile fibres and collection of signals. The disadvantage of Raman imaging such as the short focusing/working distance is also presented and discussed. Overall, the Raman imaging can extract meaningful information from the complex shower debris samples to enable analysis of microplastics.

Three-dimensional braided composite has a unique spatial network structure that exhibits the characteristics of high delamination resistance, damage tolerance, and shear strength. Considering the characteristics of braided structures, two types of high-performance materials, namely, aramid and carbon fibers, were used as reinforcements to prepare braided composites with different hybrid structures. In this study, the longitudinal and transverse shear properties of 3D braided hybrid composites were tested to investigate the influences of hybrid and structural effects. The damage characteristics of 3D braided hybrid composites under short beam shear loading underwent comprehensive morphological analysis via optical microscopy, water-logging ultrasonic scanning, and X-ray micro-computed tomography methods. It is shown that the shear toughness of hybrid braided composite has been improved at certain degrees compared with the pure carbon fiber composite under both transverse and longitudinal directions. The hybrid braided composites with aramid fiber as axial yarn and carbon fiber as braiding yarn exhibited the best shear toughness under transverse shear loading. Meanwhile, the composites with carbon fiber as axial yarn and aramid fiber as braiding yarn demonstrated the best shear toughness in the longitudinal direction. Due to the different distribution of axial and braiding yarns, the transverse shear property of hybrid braided structure excels over the longitudinal shear property. The failure modes of the hybrid braided composite under the two loading directions are considerably different. Under transverse loading, the primary failure mode of the composites is yarn fracture. Under longitudinal loading, the primary failure modes are resin fracture and fiber slip. The extensive interfacial effects and the good deformation capability of the hybrid braided composites can effectively prevent the longitudinal development of internal cracks in the pattern, improving the shear properties of braided composites.

We developed a facile strategy for the fabrication of dual-emission carbon nanodots (CDs) and demonstrated their applications for ratiometric glutathione (GSH) sensing and for differentiating cancer cells from normal cells. Dual-emission CDs were synthesized using a simple hydrothermal treatment of alizarin carmine as the carbon source, manifesting intriguing dual-emission behavior at 430 and 642 nm. With increasing GSH concentration, the fluorescence band at 430 nm increased gradually, whereas that at 642 nm decreased slightly. With monitoring of the intrinsic ratiometric fluorescence variation (I430nm/I642nm), as-prepared CDs were developed as an effective platform for ratiometric fluorescent GSH sensing, with a linear range of 1-10 to 25-150 μM and a detection limit of 0.26 μM. More importantly, confocal fluorescent imaging of cancer cells and normal cells indicated that obtained CDs could be implemented as an effective tool to visualize cancer cells with overexpressing GSH.

We recently reported (Sobhani et al., 2020) that when a confocal Raman microscope imaged a nanoplastic with the diameter of 100 nm, the imaging lateral size was 300–400 nm, due to the diffraction limit of the laser spot. In this study, we examine the lateral intensity distribution of the Raman signal emitted by nanoplastics (diameters ranging ∼30–600 nm) within the excitation laser spot. We find that the Raman emission intensity, similar to the excitation power density distributed within a laser spot, also follows a lateral Gaussian distribution. To image and visualise individual nanoplastics, we (i) decrease the mapping pixel size, in a hope to generate an image with high-resolution and simultaneously to pick up items from the “blind point”. We can then either (ii) offset the colour to intentionally image only the high-intensity portion of the Raman signal (emitted from the centre of the laser spot), to localise the exact position of the nanoplastic; or (iii) categorise the imaged nanoplastics to different groups via their Raman intensity, to simultaneously and separately visualise large nanoplastics/strong Raman signals, medium nanoplastics and small nanoplastics, in an effort to avoid the shielding and overlooking of weak signals. We (iv) also cross-check multi-images simultaneously mapped at two or three characteristic peaks via either a logic-OR or a logic-AND algorithm. Thus the imaging uncertainty can be significantly reduced from a statistical point of view.

Millions of tonnes of plastics have been released into the environment. Although the risk of plastics to humans is not yet resolved, microplastics, in the range of 1 μm - 5 mm, have entered our bodies, originating either from ingestion via the food chain or from inhalation of air. Generally there are two sources of microplastics, either directly from industry, such as cosmetic exfoliants, or indirectly from physical, chemical and biological fragmentation of large (>5 mm) plastic residues. We have found that microplastics can be generated by simple tasks in our daily lives such as by scissoring with scissors, tearing with hands, cutting with knives or twisting manually, to open plastics containers/bags/tapes/caps. These processes can generate about 0.46–250 microplastic/cm. This amount is dependent on the conditions such as stiffness, thickness, anisotropy, the density of plastic materials and the size of microplastics.This finding sends an important warning, that we must be careful when opening plastic packaging, if we are concerned about microplastics and care about reducing microplastics contamination.

Controllable feature and size, good mechanical stability and intelligent release behavior is the capsule products relentless pursuit of the goal. In addition, to illustrate the quantitative relationship of structure and performance is also important for encapsulation technology development. In this study, the sphericity and size of millimeter-scale calcium sodium alginate capsules (mm-CaSA-Caps) with aqueous core were well tuned by manipulating the viscosity, surface tension, and density of CaCl2/carboxyl methyl cellulose (CMC) drops and sodium alginate (SA) solution. The well-tuned mm-CaSA-Caps showed significant mechanical and control-releasing property effects. The results showed that the prepared mm-CaSA-Caps were highly monodispersed with average diameter from 3.8 to 4.8 mm. The viscosity of the SA solution and the viscosity and surface tension of the CaCl2/CMC solution had significant effects on the mm-CaSA-Caps sphericity. Uniform and spherical mm-CaSA-Caps could be formed with high viscosity CaCl2/CMC solution (between 168.5 and 917.5 mPa&middot, s), low viscosity SA solution (between 16.2 and 72.0 mPa&middot, s) and decreased surface tension SA solution (by adding 0.01 wt.% poloxamer 407). The diameter of the mm-CaSA-Caps could be predicted by a modified Tate&rsquo, s law, which correlated well with the experimental data. The Caps with sphericity factor (SF) &lt, 0.07 had better mechanical stability, with the crushing force 2.91&ndash, 15.5 times and the surface Young&rsquo, s modulus 2.1&ndash, 3.99 times higher than those of the non-spherical Caps (SF &gt, 0.07). Meanwhile, the spherical Caps had a more even permeation rate, which was helpful in producing uniform and sustained releasing applications in foodstuff, medicine, agriculture and chemical industry.

Chemotherapy resistance plays a major role in treatment failure of diffuse large B cell lymphoma (DLBCL). Exosomes are closely related to tumor drug resistance. Herein, the expression of exosomal proteins in DLBCL and their roles in chemotherapy resistance of DLBCL are explored. Tandem mass tag labeling proteomics was used to perform proteomic profiling in exosomes from DLBCL patients’ serum. The expression of carbonic anhydrase 1 (CA1) in parental, chemo-resistant DLBCL cells and DLBCL patient exosomes was detected. Proliferation of DLBCL following CA1 knockdown was investigated both in vitro and in vivo, along with the effects on nuclear factor κB (NF-κB) and signal transducer and activator of transcription 3 (STAT3) pathways. We identified 54 differentially expressed proteins. We validated that the expression level of exosomal CA1 was higher in chemo-resistant DLBCL cells than in chemo-sensitive counterparts. Knockdown of CA1 inhibited the growth of DLBCL via inhibiting the activation of NF-κB and STAT3 signaling pathways both in vitro and in vivo. An increased expression level of exosomal CA1 was associated with poorer prognosis, and exosomal CA1 could be used as a biomarker to predict chemotherapeutic efficacy. Our study suggests that exosomal CA1 can promote chemotherapy resistance in DLBCL via the NF-κB and STAT3 pathways, and it can serve as a biomarker for DLBCL prognosis., Graphical Abstract

© 2020 the Partner Organisations. The most frequently used approach to preparing aggregation-induced emission fluorogen (AIEgen) particles is precipitation. Therefore, the addition of an AIEgen solution into water results in the formation of AIEgen particles in a very short time. Within such a short period of time and in the absence of proper mixing under shear, AIE particles are likely to be distributed in a wide range of sizes, thereby affecting their ultimate brightness and applications. Despite numerous attempts, the size of AIEgen particles is still within the range of 200-300 nm. For the first time, we developed a facile robust and cost-effective method for the fabrication of aggregation-induced emission nanoparticles with tuneable particle sizes

Lean-electrolyte conditions are highly pursued for practical lithium (Li) metal batteries. The previous studies on the Li metal anodes, in general, exhibited good stability with a large excess of electrolyte. However, the targeted design of Li hosts under relatively low electrolyte conditions has been rarely studied so far. Herein, we have shown that electrolyte consumption severely affects the cycling stability of Li metal anode. Considering carbon hosts as typical examples, we innovatively employed in situ synchrotron X-ray diffraction, in situ Raman spectroscopy, and theoretical computations to obtain a better understanding of the Li nucleation/deposition processes. We also showed the usefulness of in situ electrochemical impedance spectra to analyze interfacial fluctuation at the Li/electrolyte interface, together with nuclear magnetic resonance data to quantify electrolyte consumption. We have found that uneven Li nucleation/deposition and the crack of surface-area-derived solid-electrolyte interface (SEI) layer both lead to a great consumption of electrolyte. Then, we suggested a design principle for Li host to overcome the electrolyte loss, that is, uneven growth of the Li structure and the crack of the SEI layer must be simultaneously controlled. As a proof of concept, we demonstrated the usefulness of a 3D low-surface-area defective graphene host (L-DG) to control Li nucleation/deposition and stabilize the SEI layer, contributing to a highly reversible Li plating/stripping. As a result, such a Li host can achieve stable cycles (e.g., 1.0 mAh cm

The physiological functions and pathological features of the vessel are related to its mechanical environment, and the mechanical properties of vessel have played the important role in the cardiovascnlar and cerebrovascular diseases. In order to quantify residual strains in aortic arch ultimately, elliptic curve fitness method which combines computerized measurements of images, are presented. And the cross-sectional configuration parameters of rabbit aortic arch in the non-loaded state, such as semi major/minor axis, thickness of arterial wall, were measured. The results of the experiment and measurement indicate that aortic arch in the non-loaded state is elliptic cross-section in its curved section but is circular cross section in its straight section. Furthermore, the whole aortic arch is cone-shaped in axial direction, which agrees well with the physiologic practice. Simultaneously, circumferential distribution of averaged thickness is nearly uniform in the non-loaded state. However, axial distribution of averaged thickness is not uniform any longer. All these results are the necessary information for further research on the mechanical features of the vessel, and corresponding numerical investigation of residual strains in vessels will be carried out in subsequent work.

Within engineering circles, overriding breakthroughs have allowed rotating mechanisms to be safely embedded under severe operational circumstances as well as harsh loads. Meanwhile, a literature survey reflects that the implementation of functionally graded materials (FGMs) has revolutionized the characteristics of rotating disks in industrial segments. One of the most challenging situations for FG rotating disks is exposure to multi-dimensional thermal shocks during heating (ascendant) and cooling (descendant), when even materials with high fracture resistance may become deficient. In this paper, a general picture is drawn of a transient thermoelastic design of FG rotating disks to mitigate failure issues stemming from ascendant/descendant thermal gradients and body forces. Contrary to the majority of reports, thermal and displacement fields of the rotating system are affected in both radial and circumferential paths in the polar system, indicating the need for two-dimensional analysis of transient heat transfer. Material properties of the geometry can be judiciously chosen in the r and θ directions, underpinning a practical recipe in the load-bearing capacity of the model for in-situ applications. Transient numerical simulations of deflections, stresses, and thermal fields of a circular annular disk are graphically elaborated using the Fourier and polynomial differential quadrature approaches. On the basis of awareness of the nature of the applied loads, it is found that an appropriate selection criterion of the variation of the material properties from among all available candidates noticeably ameliorates the impact of temperature shocks on the centrifugal force of the rotary system. With regard to the yielding criteria of the structures, the outcomes of the proposed study extend the boundaries of current traditional designs, demonstrating parallel progress in theories and viable materials.

In light of the rapid growth in microelectronic technology, triboelectric nanogenerators (TENGs) have been exploited as securely sustainable substitutes for energy scavenging purposes as well as self-powered sensory utilization. In essence, TENGs’ energy output and average power distribution depend highly on certain key parameters including contact area, the thickness of electric films and external resistance. This study attempts to predict the behavior of TENGs based on variation of those key parameters and tries to optimize the associated characteristics leading to high-output and light-weight sliding-mode TENGs. To meet this problem, an artificial intelligence approach is taken into consideration and solutions for load resistance and geometry are presented. Furthermore, an experimental setup is designed to evaluate the accuracy of the simulation results, demonstrating the precision of the applied theory. The results revealed that the predefined sliding-mode TENG can harvest 0.25 mJ at each cycle in an open-circuit condition where the weight is almost 42.91 g. Moreover, simulation proves that an appropriate value for the external resistor can increase the scavenged energy up to 3.65 mJ at each reciprocal movement. Finally, temporal responses for charge, current, voltage, power output, and harvested energy are plotted and discussed, facilitating understanding of the relationship between scavenged energy and optimized parameters.

In this paper, a distributed shell-space decomposition (DSSD) scheme is proposed for rendezvous trajectory planning of multiple autonomous marine vehicles (AMVs); this category of vehicle includes both autonomous underwater vehicles and autonomous surface vessels. The DSSD extends the concept of shell-space decomposition (SSD) by generating multiple sets of shells radiating out from the starting position of each vehicle to the rendezvous destination, enabling each vehicle to generate its trajectory within its own SSD subset. This scheme is combined with an optimized mass-center rendezvous-point selection scheme, together with a B-spline-based quantum particle swarm optimization technique to find optimal rendezvous trajectories for multiple AMVs with minimal travel time and simultaneous time of arrival for all the participating vehicles. The path planner identifies the optimal rendezvous location and generates the corresponding rendezvous trajectories based on the capabilities of each vehicle and the dynamics of the ocean environment. Simulation results show that the proposed DSSD method, combined with a novel optimized mass-center rendezvous-point selection scheme, is able to find trajectories for multiple AMVs that ensure that they reach their common destination simultaneously and with optimized time/energy consumption. A set of representative Monte Carlo simulations were run to analyze the performance of these path planners for multiple AMVs rendezvous. The results demonstrate the inherent robustness and superiority of the proposed planner based on the combined DSSD method and optimized mass-center rendezvous-point selection scheme, in comparison with other techniques.

Apoptosis is an important process for maintaining tissue homeostasis and eliminating abnormal cells in multicellular organisms. Abnormality in apoptosis often leads to severe diseases such as cancers. Better understanding of its mechanisms and processes is therefore important. Accompanying molecular biology events of apoptosis is a series of cellular morphology changes: nucleus condensation, cell shrinkage and rounding, cell surface blebbing, dynamic blebbing, apoptotic membrane protrusions and nucleus fragmentations and finally, the formation and release of apoptotic bodies. It is difficult to detect cellular changes in the early phase of apoptosis due to the subtle changes at this phase. In the current study, we induced apoptosis in HeLa cells with H2O2 and used nuclear dye Hoechst 33258, mitochondria, lysosome and cytoplasmic protein specific aggregation-induced emission fluorogens (AIEgens), TPE-Ph-In, 2M-DABS and BSPOTPE to successfully perform live cell multiplexed imaging to investigate early apoptosis cellular events. We showed the gradual dissipation of mitochondria membrane potential until it is nondetectable by TPE-Ph-In. Increased mitophagy detected by TPE-Ph-In and 2M-DABS, condensed nucleus detected by Hoechst 33258, increased permeability and/or reduced integrity of nuclear membrane, and increased intracellular vesicles detected by 2M-DABS are some of the early events of apoptosis.

© 2018 Elsevier. This manuscript version is made available under the CC-BY-NC-ND 4.0 license: http://creativecommons.org/licenses/by-nc-nd/4.0/ This author accepted manuscript is made available following 24 month embargo from date of publication (Feb 2018) in accordance with the publisher’s archiving policy, Carbon fiber reinforced polymer (CFRP) laminate normally has plastic dominant crack propagation behavior, inducing potential insecurity in the safety and reliability of structures in practical applications. In this study, we report a simple process to increase the stability of crack growth by using polydopamine (PDA) as sizing on the surface of carbon fiber (CF) fabric. The crack propagation behavior changes from a saw-tooth-shaped curve in neat CFRP laminate to a relatively smooth trending curve in PDA coated CFRP laminate with increased Mode I interlaminar fracture toughness. Enhanced impact strength and interlaminar shear strength of PDA coated CFRP laminates is also observed. A single fiber pull-out experiment and morphological study reveal that, with PDA coating on CF fabrics, cracks tend to fracture through the epoxy matrix rather than between fiber and matrix interfaces. The use of PDA as sizing on the CF contributes to improving the load transfer between the CF and the polymer matrix by enhancing the interfaces between the epoxy and the CF, increasing the friction of the fractured interface, reducing unstable crack growth, and thereby enhancing interfacial fracture toughness and impact performance.

The density functional theory (DFT) method was used to study the adsorption of CO2 molecules on pristine and doped phosphorenes. Twenty dopants were considered during this study: Fe, Co, Ni, Ti, Cu, Au, Ag, Ca, Cr, Pd, Pt, V, Sr, Mn, B, C, N, O, Si, Ge, Se, and S. Two initial configurations of CO2 on the pristine and doped phosphorenes were also studied. The results for adsorption energy, isosurface of electron density difference, partial density of states, and charge transferring analysis indicated that pristine phosphorene had a very weak interaction with CO2. Some of transition metallic dopants, namely Fe, Co, Ti, Ni, Cr, and V, significantly improved the interactions between phosphorenes and CO2. Some other metallic dopants, however, namely Au, Ag, Pd, and Pt, and nonmetallic dopants, namely Ge, Si, Se, S, N, C, B, and O had negligible effect on the interactions between CO2 and phosphorene. Cr, Fe, Ti and V-doped phosphorenes had the potential to enhance CO2 adsorption with a particular CO2 configuration. The role of charge donor or acceptor changed between CO2 and (V- Cr-, Fe-, and Ti-) doped phosphorenes when the initial CO2 configuration changed. Thus, the use of transition metallic dopants was an effective way to enhance the interactions between CO2 and phosphorene. In particular, (V- Cr-, Fe-, and Ti-) doped phosphorenes showed the potential to sense or capture CO2 molecules.

This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/ This author accepted manuscript is made available following 24 month embargo from date of publication (Sept 2017) in accordance with the publisher’s archiving policy Supplementary data to this article is available from the publisher's website: http://dx.doi.org/10.1016/j.apsusc.2017.09.243, Hydrogen capture and storage is the core of hydrogen energy application. With its high specific surface area, direct bandgap, and variety of potential applications, phosphorene has attracted much research interest. In this study, density functional theory (DFT) is utilized to study the interactions between doped phosphorenes and hydrogen molecules. The effects of different dopants and metallic or nonmetallic atoms on phosphorene/hydrogen interactions is systematically studied by adsorption energy, electron density difference, partial density of states analysis, and Hirshfeld population. Our results indicate that the metallic dopants Pt, Co, and Ni can help to improve the hydrogen capture ability of phosphorene, whereas the nonmetallic dopants have no effect on it. Among the various metallic dopants, Pt performs very differently, such that it can help to dissociate H2 on phosphorene. Specified doped phosphorene could be a promising candidate for hydrogen storage, with behaviors superior to those of intrinsic graphene sheet.

In this work, an advanced algorithm is employed to optimize the weight of a functionally graded hollow circular disk of varied thickness rotating at a constant angular velocity about its central axis. The disk is under thermoelastic load conditions. The material properties, encompassing elastic modulus thermal expansion coefficient, thermal conductivity, and density and thickness of the disk are assumed to be graded in the radial direction, and the Poisson's ratios are assumed to be constant. A combination of a co-evolutionary particle swarm optimization (CPSO) approach coupled with a differential quadrature (DQ) method is applied to obtain minimized stress and displacement fields through the geometry of the disk. The role of DQ is discretizing and solving the governing equations including motion and boundary conditions existing in the goal function of the CPSO method. In comparisons with other optimization results in the literature, the weight reduction results of this algorithm show much superior responses, demonstrating the effectiveness of this algorithm for optimizing constrained complex problems in engineering structures. Also, in numerical simulation, a study is performed to determine the effects of angular velocity and gradient index variations on the distribution of stress and displacement fields.

Copper hydroxyphosphate, Cu2PO4OH, with various architectures was synthesized by adjusting pH values in a simple hydrothermal route. The photocatalytic activity of the Cu2PO4OH hierarchical superstructures was strongly related to their micro-morphology, as demonstrated by the degradation of eosin Y dye with a solar simulator. Excellent photocatalytic performance was achieved by Cu2PO4OH obtained under the pH values of 7 and 5. The antibacterial properties of the Cu2PO4OH complex superstructures were also explored by Escherichia coli (ATCC 8739) culturing. Cu2PO4OH showed apparent antibacterial properties but the samples obtained under the pH values of 5 and 7 exhibited better antibacterial properties than those of the Cu2PO4OH under the pH value of 2.5. Thus, Cu2PO4OH can be a promising photocatalyst with excellent antibacterial properties achieved by simply controlling its hierarchical superstructures by adjusting the pH values during feasible synthesis.

A novel continuous flow turbo-thin film device (T2FD) has been developed. The microfluidic platform is effective in high yielding production of biodiesel from wet microalgae at room temperature under continuous flow conditions. These findings open the possibility of cost effective production of biodiesel directly from wet microalgae.

We present a 53-year-old woman who had shortness of breath and atypical chest pain and underwent Tc-sestamibi myocardial perfusion imaging to detect coronary artery disease. The raw data in cine format showed an incidental focus close to the heart, and SPECT/CT fused images revealed a focus of intense uptake in the left breast. The subsequent histopathologic findings and F-FDG PET/CT imaging confirmed the diagnosis as primary breast lymphoma. After 3 cycles of chemotherapy, previously visualized abnormal uptake in the left breast disappeared on the follow-up PET/CT.

Fluorinated graphene (FG) as energetic material has a wide range of application due to its unique light-to-heat conversion, thermal and oxidation properties. The structure of FG, especial the fluorinated degree of FG is a key parameter to achieve those applications. In this study, the effect of the fluorinated degree of FG on the laser ignition of a typical energetic material of 2,4,6,8,10,12-(hexanitrohexaaza) cyclododecane (CL-20) was studied by the density functional theory (DFT) calculations and experimental characterizations. The interaction mechanism between the FG and CL-20 was studied by the simulation through adsorption energy and the electron density difference variations. Simultaneously, graphene materials with different fluorinated degrees were prepared by the hydrothermal method experimentally, the photothermal conversion behavior and laser ignition characteristics of graphene with different degrees of fluoride were characterized. Simulation and experimental results show that CL-20 and graphene with a low degree of fluorination have stronger adsorption energy and lower laser induced ignition delay time than those of the other conditions. This research provides an atomic-scale explanation for the laser induced ignition mechanism of fluorinated graphene in energetic materials.

Youhong Tang and Dan Ding introduce the Materials Chemistry Frontiers themed collection on luminogenic bioprobes for personal health technologies.

The potential hazards of glyphosate on human health and ecological system cause widespread concern while being extensively accepted as a low side effects herbicide. Carbon based adsorbents are promising candidates for removal glyphosate. In this study, the ab initio calculations are carried out to explore the effects of ten different elemental dopants on the glyphosate capture ability of graphene. The results indicate that elemental doping can be an effective way to improve the interactions between glyphosate and graphene. Considering the interactions between dopants and graphene, including their interfacial interactions, Cu-, O- and Pd-doped graphenes are outstanding candidates for glyphosate adsorbents.

Defect-dominated regulation on water adsorption or dissociation on calcite surface is crucial in several important areas including the geochemistry of calcite, haze formation, which is caused by calcite based mine dust, inorganic material design and so on. Here, density functional theory (DFT) method has been utilized to systematically investigate the behavior of water on various calcite {1 0 4}surfaces, focusing on the effect of defects, including doping defected (Co-, Mg-, Mn-, Zn-, and Cu-doped), vacancy-defected (Ca or CO3), and the interstitial O calcite {1 0 4} surfaces. As demonstrated, although all the defects enhance the water adsorption, the enhancement degree varies with the defects type that the vacancy defects exhibit more remarkable role. The activation energy of water dissociation is greatly related to the integrated crystal orbital Hamilton populations (ICOHP) energy of the dopants - O of water atom pairs in the water-calcite {1 0 4} surface interaction systems. It indicates that water is easily dissociated on - CO3 vacancy-defected calcite {1 0 4} surface. Our study can be helpful for the understanding of the water adsorption and dissociation on defected calcite surfaces.

Carbon nanotubes (CNTs) are easy to agglomerate, which results in poor structure reproducibility, and seriously restricts the improvement of conductivity and electromagnetic interference (EMI) shielding properties of CNTs composites. In this study, CNTs were evenly dispersed in the chitosan (CS) matrix by a high energy mechanical ball milling method, and three-dimensional (3D) printing ink of CNTs/CS was obtained. The CNTs/CS composites with porous network structures are prepared by the 3D printing technology. The results show that the 3D porous network CNTs/CS composites can effectively absorb electromagnetic waves. The 3D printed CNTs/CS composites with porous networks show an exceptional EMI shielding effectiveness of 25.07 dB at a low density of 72 mg/cm3. According to the square hole grid structure of 3D printed products, the influence of pore size and conductivity of the composites on the EMI shielding performance is simulated and analyzed, which are consistent with the experimental results. For non-magnetic materials, conductivity has a greater influence on the EMI shielding performance than that of pore size. This study provides a new idea and method for the rapid and accurate preparation of polymer matrix composites with excellent EMI shielding properties as surface of electronic components.

Red fluorescent carbon dots (R-CDs) have been developed for the “turn-on” determination of pH and tetracycline antibiotics (TCs), including tetracycline (TC), oxytetracycline (OTC), and chlortetracycline (CTC). The CDs were fabricated via one-pot hydrothermal treatment using neutral red and thiourea as precursors. As-obtained CDs possess excellent photobleaching resistance, good photostability and biocompatibility, and low cytotoxicity. Importantly, the CDs displayed a remarkable emission enhancement upon the introduction of TCs based on aggregation induced emission enhancement (AIEE) mechanism. For TC, OTC, and CTC, the linear correlation detection ranges are 3 − 35 μM, 2 − 50 μM, and 5 − 50 μM, respectively, and the limit of detections are 12, 23, and 25 nM, respectively. The proposed method has been successfully applied to the determination of TCs in milk products. Furthermore, the CDs exhibited a distinct H+-sensitive feature, and have been used to construct fluorescent pH sensor in linear range of 6.0–8.0 with a pKa of 7.08. Notably, the nanosensor has been also extended to monitor TCs and pH in cellular systems, demonstrating the proposed methodology presents promising biosensing application prospect.

The purpose of this study is to provide some insights into the phase mechanism of a cylindrical vortex–induced vibration. A transient coupled fluid–structure interaction numerical model is adopted to simulate a cylindrical vortex–induced vibration. The vortex shedding around the cylinder is investigated numerically by a two-dimensional large eddy simulation approach which can catch more details of the flow field and more accuracy on computing hydrodynamic forces. The vortex shedding modes and response and hydrodynamic forces of a cylindrical vortex–induced vibration are acquired with varied frequency ratios. According to differences in the vortex shedding location, the vortex wake can be characterized by two kinds of mode, the “first mode” and the “second mode.” The mechanisms behind the phases of the first mode and the second mode vortex wakes are investigated, and it is found that the flow speed induced by a cylindrical transverse vibration and the position of a vortex release are the root causes of the phase difference between the lift coefficient and transverse displacement. The speeds caused by a cylinder vibration and a cylinder-shed vortex are the reasons that the lift amplitude of an oscillatory cylinder is different from that of a fixed cylinder.

Burkitt lymphoma (BL) is a highly aggressive B-cell neoplasm. Although BL is relatively sensitive to chemotherapy, some patients do not respond to initial therapy or relapse after standard therapy, which leads to poor prognosis. The mechanisms underlying BL chemoresistance remain poorly defined. Here, we report a mechanism for the relationship between the phosphorylation of STAT3 on Tyr705 and BL chemoresistance. In chemoresistant BL cells, STAT3 was activated and phosphorylated on Tyr705 in response to the generation of the reactive oxygen species (ROS), which induced Src Tyr416 phosphorylation after multi-chemotherapeutics treatment. As a transcription factor, the elevated phosphorylation level of STAT3Y705 increased the expression of GPx1 and SOD2, both of which protected cells against oxidative damage. Our findings revealed that the ROS-Src-STAT3-antioxidation pathway mediated negative feedback inhibition of apoptosis induced by chemotherapy. Thus, the phosphorylation of STAT3 on Tyr705 might be a target for the chemo-sensitization of BL.

This paper investigates capability and efficiency of utilizing the inverse dynamics in the virtual domain (IDVD) method to provide the real-time updates of feasible trajectory for an autonomous underwater vehicle (AUV) during underwater docking operations. The applicability of the IDVD method is examined for two scenarios. For the first scenario, referred to as an offline scenario, a nominal trajectory may be generated ahead of time based on a priori knowledge about the docking station (DS) pose (position and orientation). The second scenario, referred to as an online scenario, assumes some uncertainty in the DS pose; hence, the reference trajectory needs to be constantly recomputed in real time based on the updates about the DS pose. The offline scenario solution serves as a benchmark solution to check feasibility and optimality of generated trajectory subject to constraints on the states and controls. In particular, the offline solution can assist in making informed trade-off decisions between optimality of solution and computational efficiency. For the relatively simple offline scenario, the IDVD-method solution is compared with the Legendre–Gauss–Lobatto pseudo-spectral (LGLPS) method solution. The software-in-the-loop simulations and Monte Carlo trials are run for robustness assessment. Finally, the potential for the IDVD method to work online, in a closed-loop guidance system, is explored using a realistic cluttered operational simulation environment. Simulation results show that the IDVD-method based guidance system guarantees a reliable and efficient docking process by generating computationally efficient, feasible and ready to be tracked trajectories.

Adhesive hydrogels are attractive biomaterials for various applications, such as electronic skin, wound dressing, and wearable devices. However, fabricating a hydrogel with both adequate adhesiveness and excellent mechanical properties remains a challenge. Inspired by the adhesion mechanism of mussels, we used a two-step process to develop an adhesive and tough polydopamine-clay-polyacrylamide (PDA-clay-PAM) hydrogel. Dopamine was intercalated into clay nanosheets and limitedly oxidized between the layers, resulting in PDA-intercalated clay nanosheets containing free catechol groups. Acrylamide monomers were then added and in situ polymerized to form the hydrogel. Unlike previous single-use adhesive hydrogels, our hydrogel showed repeatable and durable adhesiveness. It adhered directly on human skin without causing an inflammatory response and was easily removed without causing damage. The adhesiveness of this hydrogel was attributed to the presence of enough free catechol groups in the hydrogel, which were created by controlling the oxidation process of the PDA in the confined nanolayers of clay. This mimicked the adhesion mechanism of the mussels, which maintain a high concentration of catechol groups in the confined nanospace of their byssal plaque. The hydrogel also displayed superior toughness, which resulted from nanoreinforcement by clay and PDA-induced cooperative interactions with the hydrogel networks. Moreover, the hydrogel favored cell attachment and proliferation, owning to the high cell affinity of PDA. Rat full-thickness skin defect experiments demonstrated that the hydrogel was an excellent dressing. This free-standing, adhesive, tough, and biocompatible hydrogel may be more convenient for surgical applications than adhesives that involve in situ gelation and extra agents.

This contribution reports the synthesis, characterization and application of a new ternary homo-heterojunction photocatalyst for improved hydrogen production via water-splitting. The heterostructure is constructed by soft-grafting of graphitic carbon nitride (GCN) and graphene oxide (GO) into an amorphous carbon nitride (ACN) substrate. In this ternary hybrid, a cascaded redox-junction is formed that significantly facilitates the separation of photogenerated electron–hole pairs (EHPs), retards EHP recombination and shuttles electrons to the photocatalyst/liquid interface for proton reduction reactions. When deposited with 3 wt% Pt as a cocatalyst, this new photocatalyst exhibits hydrogen production of 251 μmol h−1 from 10 vol% aqueous triethanolamine solution under visible light (420 nm) irradiation with an apparent quantum efficiency of 6.3%. This ternary photocatalyst therefore outperforms stand-alone/binary photocatalysts and promises to be a viable alternative to metal-based photocatalysts.