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The production and advanced treatments of bacterial cellulose (BC) and its composites have garnered increased attention in the past decades. As a biodegradable polymer, BC possesses remarkable purity, super-fine nanonetwork structure, biocompatibility, and excellent mechanical properties, which could satisfy the most needs of application areas. The comprehensive knowledge of different BC treatment methods is critical to property modification through composite formation towards multifunctional applications. In this review, we summarised three BC treatment methods and relevant functional composite construction processes, especially the emerging breaking-refactoring methods. It is known that the structure-property-application relationship of BC composites is tightly linked. The successful development of multifunctional BC-based composites will rely on good sustainability and exploration of BC-based composite preparation technology. Applications of BC and its composites based on those treatment methods are reviewed. The properties and characteristics underlying these approaches to BC and its composite applications are also discussed here. [ABSTRACT FROM AUTHOR]

Crumb rubbers exhibit extensive potential applications as infrastructure materials due to the low elastic modulus. Nevertheless, the poor interfacial adhesion between rubber crumb and cement matrix limits the scale applications of crumb rubbers in cement-based composites. In this study, mussel-inspired modification of crumb rubbers is investigated. The hydrophilicity of rubber surface has apparently improved after polydopamine (PDA) modification. Effects of the surface modifications of rubbers on the compressive strength, fluidity, and tribology behaviors of rubberized mortars have been systematically characterized. The superiority of PDA modification for crumb rubbers has been demonstrated by comparing those with the other polyphenol modifications and the routine oxidation modification. The compressive strength of the PDA modified rubber cement mortar increases by 37% comparing with that of the ordinary rubber cement mortar. The mechanical and low-temperature tribology behaviors of PDA-rubberized mortars indicate a promising way to improve the service performance of the rubberized mortars and concretes. [ABSTRACT FROM AUTHOR]

The development of fluorescent gels, if not the current focus, is at the center of recent efforts devoted to the invention of a new generation of gels. Fluorescent gels have numerous properties that are intrinsic to the gel structure, with additional light-emitting properties making them attractive for different applications. This review focuses on current studies associated with the development of fluorescent gels using aggregation-induced emission fluorophores (AIEgens) to ultimately suggest new directions for future research. Here, we discuss major drawbacks of the methodologies used frequently for the fabrication of fluorescent gels using traditional fluorophores compared to those using AIEgens. The fabrication strategies to develop AIE-based fluorescent gels, including physical mixing, soaking, self-assembly, noncovalent interactions, and permanent chemical reactions, are discussed thoroughly. New and recent findings on developing AIE-active gels are explained. Specifically, physically prepared AIE-based gels including supramolecular, ionic, and chemically prepared AIE-based gels are discussed. In addition, the intrinsic fluorescent properties of natural gels, known as clustering-triggered fluorescent gel, and new and recent relevant findings published in peer-reviewed journals are explained. This review also revealed the biomedical applications of AIE-based fluorescent hydrogels including drug delivery, biosensors, bioimaging, and tissue engineering. In conclusion, the current research situation and future directions are identified. [ABSTRACT FROM AUTHOR]

A bidirectional fluid–structure coupling method was developed to comprehensively understand the VIV characteristics of a 3D flexible marine riser. Through study VIV characteristics of the 3D riser in different flow conditions and by analysis of the structural characteristics of the riser's responses, this study successfully captured the phenomena of switching of adjacent-order vibration modes and the characteristics of a "traveling wave" and a "standing wave" at both ends of the riser that cannot be obtained from 2D VIV studies. Analysis of the frequency of the structural vibration response characteristics found that the 3D flexible riser VIV showed multi-frequency vibration phenomena and the vibration response characteristics of a broadband spectrum in a high-speed flow condition. This research distinguished vortex forms at different locations of the riser, i.e., in the middle of the riser, mainly the "2P" or "P + S" forms occurred and at both ends of the riser, mainly the "2S" form appeared. After comparative analysis of the vortex forms of the riser wake in different speed flow conditions, this research identified that under a low flow velocity, the riser showed a 3D effect marginally, whereas under a high flow velocity, the riser showed a strong 3D effect. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Lipid bodies are dynamic organelles of photosynthetic microalgae that can be used as the third generation resources for biofuel production. Biosynthesis of lipids can be influenced by different signalling processes. Visualisation of these processes can provide useful information about the fate and associated roles of lipid molecules in different biological systems. In photosynthetic organisms, however, studies of calcium ediated lipid biosynthesis is bottlenecked due to the limitation of proper and efficient technologies, which also include visualisation techniques. Currently, most studies to visualise lipid droplets in vivo have used traditional dyes, and proper visualisation of lipid drops is hindered by dye-specific limitations. This hurdle could be overcome by using recently developed aggregation-induced emission biooprobes. This review reveals current knowledge gaps in the studies of lipid drops and calcium ions in microalgae, as calcium signaling is important secondary messenger to detect a wide variety of environmental stimuli in plant and animal cells. To obtain insight into the mechanisms of these processes, the merits and demerits of currently available visualisation techniques for lipid drops and calcium are also detailed. Finally, opportunities and possibilities are proposed to recommend further improvement of techniques for detecting the role of calcium during lipid formation in microalgae for biofuel production. [ABSTRACT FROM AUTHOR]

In the light of the increasing growth of requests for applicable energy accounts, this study is driven by the desire to determine the energy interactions among the electrical, thermal and mechanical fields in pyroelectric shell structures. The principal purpose of the proposed work is to scrutinize how material properties synthesize new smart systems exhibiting higher levels of electrical energy while possessing considerably lower weight. To achieve such an aim, it is assumed that the material properties of the elastic medium would be graded through the thickness and the mechanical, electrical and thermal fields would have their own independent gradient indexes. If we nominate the grading indexes as design variables, the material elements of the solid should be appropriately functionalized, avoiding any problems stemming from the low electrical outputs of shell structures in energy-harvesting applications. To untangle the complex mathematics governing this problem, a skilfully merged algorithm of an advanced optimization method with two semi-analytical approaches is exploited. When the simulation is implemented, a significant increment in electrical energy in conjunction with a marked reduction in weight is reported. Further, the effects of inhomogeneity and thermal gradient on the electrostatic energy and weight, as well as the stress, displacement, electrical and thermal fields are graphically presented and discussed. With its material development and structural integrity, this study presents an efficient and cost-effective criterion for smart structures for scavenging energy from available thermo-electromechanical energy sources. [ABSTRACT FROM AUTHOR]

Fluorescence imaging is an important branch of bioimaging. It is non-invasive and provides superior spatial and temporal resolution during the real-time monitoring of biological samples of interest. Although the spatial resolution limit of optical microscopes is about 200 nm, due to the diffraction limit, with the application of super-resolution fluorescence microscopy technologies this limit has been pushed below 30 nm. This makes it feasible to visualize biological structures in subcellular levels and to monitor subcellular biological processes in real time. However, due to the complexity of the biological structure and components within cells, simultaneous staining and monitoring multiple intracellular components with different coloured fluorophores is often needed during multiplex imaging, to better understand biological processes. Aggregation-induced emission luminogens (AIEgen) and AIEgen based nanoparticles (NPs) have presented many advantages in fluorescence imaging, with strong potential for biological science and nano-medicine. Herein this review, we focus on the advantages of AIEgen and AIEgen NP in cell-based fluorescence imaging, and the latest advances of AIEgens in cell-based multiplex imaging are summarized and discussed. The future perspectives are proposed. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The flow-induced vibration of a cylindrical structure is a very common problem in marine environments such as undersea pipelines, offshore risers, and cables. In this study, the vortex-induced vibration (VIV) of an elastically mounted cylinder at a low Reynolds number is simulated by a transient coupled fluid-structure interaction numerical model. Considering VIV with low damping ratio, the response, hydrodynamic forces, and vortex shedding modes of the cylinder is systematically analyzed and summed up the universal rule under different frequency ratios. On the basis of the analysis, we find that the frequency ratio α is a very important parameter. It decides the locked-in, beat, and phase-switch phenomena of the cylinder, meanwhile, it also influence the vortex mode of the cylinder. The trajectory of the two degrees of freedom (2 DOF) case at different natural frequency ratios is discussed, with most trajectories having a 'figure of 8' shape and a few having a 'crescent' shape. A fast Fourier transformation technique is used to obtain the frequency characteristics of the vibration of the cylindrical structure. Using the 2 DOF cylinder model in place of the 1 DOF model presents several advantages in simulating the nonlinear characteristics of cylindrical structures, including the capacity to model the crosswise vibration generated by in-line vibration. [ABSTRACT FROM AUTHOR]

In sailing regattas, the actions of sailboats are to meet, overlap, pursue, pass, anti-collide, and defend. The aerodynamic performance of a sail based on a numerical simulation method is reported in this study. The parameters affecting the sail's aerodynamic force coefficients, namely sailing angle, attack angle, mast shape, pitch angle, and camber ratio, are analyzed. From the results, basic principles and corresponding tactics of sail trimming are discussed and recommended for the start, during the windward, running, and leeward legs, before the finish, and near the marks. Sailors in the regatta should decrease the interaction of air flows around the sail to increase the lift force. The sailing angle, attack angle, pitch angle, and camber ratio should be adjusted to the appropriate degree to speed the boat when it is balanced. Sail trimming tactics have been practiced by professional sailors in regattas during which they can be scientifically supervised to compete against each other at Olympic Games. [ABSTRACT FROM AUTHOR]

In this research, we synthesized superabsorbent polymers (SAPs) based on poly(acrylic acid) with super adsorption properties through a novel one-step cost-effective method. The SAPs' adsorption for removal of heavy metal ions [e.g., Cu(II)] from aqueous solutions was systematically studied. The effects of pH (2.0-5.0), sodium hydroxide and water composition, contact time (0-48 h), and initial Cu(II) ion concentrations (1-500 mg dm) on the adsorption of Cu(II) ions were studied using atomic absorption spectroscopy. The adsorption behavior was fitted to a Langmuir isotherm and shown to follow a pseudo-second-order reaction model. The maximum adsorption capacities of Cu(II) ions were shown to be 243.91 mg g for sodium polyacrylate (PAANa), which is among the highest adsorption capacities reported in the literature. The superior adsorption capacity of Cu(II) ions is attributed to the chelating ability of functional groups (e.g., -COO) in the PAANa matrix. The recyclability of the PAANa material showed that over 98.92 % of the adsorbed copper could be recovered in a mild concentration (0.01 M) of nitric acid. Results of three consecutive adsorption-desorption cycles showed that the composites had high adsorption and desorption efficiency, implying that PAANa samples can be recycled and reused as an effective adsorbent for Cu(II) recovery. [ABSTRACT FROM AUTHOR]

A novel water-swellable rubber (WSR) composite, modified by a compatibiliser, was prepared by blending poly(dimethylsiloxane) rubber (PDMS) as a matrix and poly(acrylic acid) (PAA) partially neutralised by sodium hydroxide (NaOH) as a superabsorbent polymer. The addition of hydrophilic PAA into hydrophobic PDMS improved water swelling ability but without good durability, mainly due to the poor interfaces between PAA and PDMS. Meanwhile, the tensile properties of the WSR before and after swelling decreased dramatically. With NaOH added as the neutraliser for PAA or with aminopropyltriethoxysilane added as the compatibiliser for PDMS and PAA, water swelling ability and/or durability increased. However, when the compatibiliser and the neutraliser were added together, the water swelling ability and durability of the WSR composites further increased by virtue of the synergistic effects due to the increased interfacial cohesion between the PDMS and PAA. [ABSTRACT FROM AUTHOR]

This paper presents an on-line dynamic path re-planning system for an autonomous underwater vehicle (AUV) to enable it to operate efficiently in a spatiotemporal, cluttered, and uncertain environment. The proposed strategy combines path re-planning with an evolutionary algorithm to adapt and regenerate the trajectory during the course of the mission using continuously updated current profiles from on-board sensors, such as a Horizontal Acoustic Doppler Velocity Logger. A quantum-behaved particle swarm optimization (QPSO) algorithm is used with a cost function which is based on the total time required to travel along the path segments accounting for the effect of space-time variable currents. The proposed path planner is designed to generate an optimal trajectory for an AUV navigating through a spatiotemporal ocean environment in the presence of irregularly shaped terrains as well as obstacles whose position coordinates are uncertain. Simulation results show that using the same on-board computation resources, the proposed path re-planning methodology with reuse of information gained from the previous planning history is able to obtain a more optimized trajectory than one relying on reactive path planning. Subsets of representative Monte Carlo simulations were run to analyse the performance of these dynamic planning systems. The results demonstrate the inherent robustness and superiority of the proposed planner based on path re-planning scheme when compared with the reactive path planning scheme. [ABSTRACT FROM AUTHOR]

Hyperbranched polymers or/and graphene oxide nanosheets were used to synthesize poly(acrylic acid)-based hybrid hydrogels with high water absorption ability, excellent mechanical properties, and environmental remediation abilities through a novel one-step, cost-effective, and environmentally friendly method. The combination of hyperbranched polymers and graphene oxide nanosheets had synergistic effects on the final hybrid hydrogel, especially on the mechanical behaviors of the hydrogels, with Young's modulus, tensile strength at break and elongation at break increasing by 69, 308, and 848 %, respectively, while the other properties remained similar to those of pure poly(acrylic acid). The proposed enhancement mechanism is also discussed. [ABSTRACT FROM AUTHOR]

Serious wear-out failure in conical picks leads to low working efficiency when mining protective seams using a coal auger. In this study, to decrease the wear of conical picks in the rotation-drilling cutting process, an interference model of rotation-drilling cutting is established according to coal cutting theory. Then, laboratory rotation-drilling cutting experiments with 28 different cutting angles δ and rotation angles ε are realized on large blocks of test coal wall using one type of conical pick to verify the interference model. The experimental results show that the wear of picks increased gradually with an increase in rotation angle and a decrease in cutting angle. The rotation-drilling cutting experiments verify the correctness of the interference theory model. It is preferable to choose a small rotation angle and large cutting angle when deciding on the installation parameters of conical picks in the theoretical range. [ABSTRACT FROM AUTHOR]

In this study, two thermotropic liquid crystalline polyesters (TLCPs) synthesized by polycondensation of p-hydroxybenzoic acid /hydroquinone/ poly dicarboxylic acid were used as viscosity reduction agents for polyethylene (PE). The TLCPs had different thermal, rheological and other physical properties that were quantitatively characterized. The two TLCPs were blended with high density PE (HDPE) and high molecular mass PE (HMMPE) by simple twin screw extrusion under the same weight ratio of 1.0 wt% and were each rheologically characterized at 190°C. The TLCPs acted as processing modifiers for the PEs and the bulk viscosity of the blends decreased dramatically. However, the viscosity reduction ability was not identical: one TLCP had obviously higher viscosity reduction ability on the HDPE, with a maximum viscosity reduction ratio of 68.1%, whereas the other TLCP had higher viscosity reduction ability on the HMMPE, with a maximum viscosity reduction ratio of 98.7%. Proposed explanations for these differences are evaluated. [ABSTRACT FROM AUTHOR]

In the present work, the effect of loading rate on indentation creep was studied. Indentation creep tests were conducted on epoxy resin to provide creep deformation under constant load, contact creep compliance and cut-off time using a Berkovich indenter. Several loading rates, ranging from 0.25 to 6 mN/s, were used to perform the tests. The results showed that there is a strong loading rate dependence on creep response of the epoxy resin under indentation. Contact creep compliance and cut-off time decreased with increasing loading rate. In contrast, an increase in reduced modulus, hardness, displacement variation and contact creep compliance variation during the holding time was noticed. The loading rate sensitivity on creep response under indentation can be attributed to viscoelastic response prior to holding segment and strain rate effect on yield stress of the epoxy resin. This study provided an insight to understand the loading rate dependence on creep behaviour of epoxy resin under indentation. [ABSTRACT FROM AUTHOR]

In the present study, we employed proteomic methods to identify and quantitate differentially expressed proteins between diffuse large B cell lymphoma (DLBCL) tissues with low and high sensitivity to combinatorial cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) chemotherapy and explored protein networks associated with DLBCL chemoresistance to CHOP. For proteomics analysis, DLBCL tissues were collected from 14 untreated patients. Two-dimensional gel electrophoresis combined with mass spectrometry (MS) were employed to identify and quantitate differentially expressed proteins in DLBCL tissues with low or high sensitivity to CHOP chemotherapy in vitro. Nineteen proteins showing an over twofold change in the MS/MS ions score between the low sensitivity and the high sensitivity groups were identified as differentially expressed proteins and confirmed by Western blot analyses. Immunohistochemical analyses were performed in DLBCL tissue samples from 98 patients who had received four cycles of CHOP chemotherapy, which showed that expressions of the identified CHOP sensitivity biomarkers were significantly associated with therapeutic outcomes of DLBCL, suggesting that the biomarkers could be used to predict DLBCL patient outcomes. This study provides important insights into understanding the molecular basis for development of multi-drug chemoresistance in DLBCL, which may serve as a basis for identification of novel therapeutic targets and biomarkers involved in the emergence and maintenance of DLBCL resistance to CHOP. [ABSTRACT FROM AUTHOR]

A thermotropic liquid crystalline polymer (TLCP) blend with 1 wt% multiwall carbon nanotubes (MWCNTs) was prepared by melt compounding. Morphological observations of the blend show that the chemical-treated MWCNTs were well dispersed in the TLCP matrix with a good interface. MWCNTs have little effects on the thermal and rheological properties of pure TLCP. TLCP fibers with and without MWCNTs were prepared at certain drawing ratios by a melt spinning method. The degree of orientation of TLCP chains is enhanced by MWCNT micro-clusters during the fiber formation. The mechanical properties of TLCP/MWCNT fibers are significantly increased by 34.5 % for tensile strength and 38.0 % for tensile modulus in comparison with those of pristine TLCP fibers, due to the synergistic effects of MWCNT and TLCP. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented regarding the case of a 60-year-old woman who was diagnosed with metastatic carcinoma in the thyroid gland associated with lymphoid tissue B cell lymphoma and HT.