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This minireview summarizes the recent cutting-edge works of 2D MXene-based flexible antennas, discusses the existing bottlenecks, and provides some guidelines for the future development of this promising field.

A totally new SERS technology, MBene-enhanced Raman scattering, is developed by employing MBene as a SERS-active material. An ordered vacancy-triggered highly sensitive MBene-based SERS platform with superior signal uniformity is designed.

Environmental concerns are driving interests in post-petroleum synthetic textiles produced from microbial and fungal sources. Bacterial cellulose is a promising sustainable leather alternative, on account of its material properties, low infrastructure needs and biodegradability. However, for alternative textiles like bacterial cellulose to be fully sustainable, alternative ways to dye textiles need to be developed alongside alternative production methods. To address this, we here use genetic engineering ofKomagataeibacter rhaeticusto create a bacterial strain that grows self-dyeing bacterial cellulose. Dark black pigmentation robust to material use is achieved through melanin biosynthesis in the bacteria from recombinant tyrosinase expression. Melanated bacterial cellulose production can be scaled up for the construction of prototype fashion products, and we illustrate the potential of combining engineered self-dyeing with tools from synthetic biology, via the optogenetic patterning of gene expression in cellulose-producing bacteria. With this work, we demonstrate that combining genetic engineering with current and future methods of textile biofabrication has the potential to create a new class of textiles.

Cellulose fiber materials suitable for filtering, insulation, protective, and hygiene applications can be formed using aqueous foam as a carrier phase. The subtle fiber–bubble interaction provides a tool which can be utilized to alter both structural and mechanical material properties. Earlier model surface studies have only indicated clear surface-bubble adhesion when both the surface hydrophobicity and surface tension of the solution are high enough. In this work, we first show that for silica model surfaces these basic mechanisms are similar for both nonionic polyethylene glycol sorbitan monolaurate (Tween 20) and anionic sodium dodecyl sulfate (SDS) surfactants. In the second step, thick nonwoven materials were foam formed from hydrophilic or hydrophobic viscose fibers using small amounts of cellulose microfibers (CMFs) to form a bonding agent. There was a clear variation in structure and strength properties between the samples made using different fibers and surfactants. The partial alignment and layering of fibers in the wet foam led to anisotropy in the mechanical properties of the formed samples. Using SDS, the fiber alignment was very strong for hydrophilic fibers but was reduced for hydrophobic fibers because of stronger coupling to bubbles during structure forming, impacting the microscale fiber network. For nonionic Tween 20, in addition to surfactant adsorption on the fibers, the ethoxylated surfactant headgroups are suggested to form bridges between CMFs and other fibers, restricting fiber movements during formation. For hydrophilic fibers, this showed up as a lower in-plane compression modulus but higher transverse strength for Tween 20 compared with SDS surfactant. For hydrophobic fibers, the sensitivity of the mechanical properties on surfactant type was even stronger.

Bacteria proficient at producing cellulose are an attractive synthetic biology host for the emerging field of Engineered Living Materials (ELMs). Species from the Komagataeibacter genus produce high yields of pure cellulose materials in a short time with minimal resources, and pioneering work has shown that genetic engineering in these strains is possible and can be used to modify the material and its production. To accelerate synthetic biology progress in these bacteria, we introduce here the Komagataeibacter tool kit (KTK), a standardised modular cloning system based on Golden Gate DNA assembly that allows DNA parts to be combined to build complex multigene constructs expressed in bacteria from plasmids. Working in Komagataeibacter rhaeticus, we describe basic parts for this system, including promoters, fusion tags and reporter proteins, before showcasing how the assembly system enables more complex designs. Specifically, we use KTK cloning to reformat the Escherichia coli curli amyloid fibre system for functional expression in K. rhaeticus, and go on to modify it as a system for programming protein secretion from the cellulose producing bacteria. With this toolkit, we aim to accelerate modular synthetic biology in these bacteria, and enable more rapid progress in the emerging ELMs community.

As a type of micro flat loop heat pipe, s-UTLHP (silicon-based ultra-thin loop heat pipe) is of great significance in the field of micro-scale heat dissipation. To prove the feasibility of s-UTLHP with high heat flux in a narrow space, it is necessary to study its heat transfer mechanism visually. In this paper, a structural design of s-UTLHP was proposed, and then, to realize the working fluid charging and visual experiment, an experimental system including a holding module, heating module, cooling module, data acquisition module, and vacuum chamber was proposed. Deionized water was selected as a working fluid in the experiment. The overall and micro phenomena of s-UTLHP during startup, as well as the evaporation and condensation phenomena of s-UTLHP during stable operation, were observed and analyzed. Finally, the failure phenomenon of s-UTLHP was analyzed, and several solutions were proposed. The observed phenomena and experimental conclusions can provide references for further related experimental research.

The biodegradation of polyacrylamide (PAM) includes the hydrolysis of amino groups and cleavage of the carbon chain; however, the effect of molecular weight on the biodegradation needs further investigations. In this study, biodegradation of low molecular weight PAM (1.6 × 106 Da) was evaluated in two aerobic (25 °C and 40 °C) and two anaerobic (35 °C and 55 °C) reactors over 100 days. The removal of the low molecular weight PAM (52.0–52.6%) through the hydrolysis of amino groups by anaerobic treatment (35 °C and 55 °C) was much higher than that of the high molecular weight (2.2 × 107 Da, 11.2–17.0%) observed under the same conditions. The molecular weight was reduced from 1.6 × 106 to 6.45–7.42 × 105 Da for the low molecular weight PAM, while the high molecular weight PAM declined from 2.2 × 107 to 3.76–5.87 × 106 Da. The results showed that the amino hydrolysis of low molecular weight PAM is easier than that of the high molecular weight one, while the cleavage of its carbon chain is still difficult. The molecular weights of PAM in the effluents from the two aerobic reactors (25 °C and 40 °C) were further reduced to 4.31 × 105 and 5.68 × 105 Da by the biofilm treatment, respectively. The results would be useful for the management of wastewater containing PAM.

Disparate roles exist for tumor-associated macrophages in breast cancer growth and progression. The aim of this study was to explore the influence of induced macrophages on the growth of breast cancer cells. THP-1 monocytes were differentiated to macrophages using phorbol 12-myristate 13-acetate. The effect of the medium from THP-1 monocytes or macrophage-conditioned medium (MφCM) on MCF-7 (estrogen receptor and progesterone-positive positive) and MDA-MB-231 (MB; triple-negative) breast cancer cells was determined at 24 h, 48 h and 72 h. Assays were conducted for cell viability, apoptosis, proliferation and cell phenotype, and quantitative real-time polymerase chain reaction (qRT-PCR) for expression of associated genes. MφCM inhibited proliferation of MCF-7 and MB cells in a time-dependent manner and, in particular, decreased viability of MCF-7 cells. MφCM induced a markedly vacuolated phenotype in MCF-7 increased apoptosis in MCF-7 cells, but correlative changes in Bcl-2 or Bax were absent. A multifold and significant reduction in anti-apoptotic Bcl-2 in MB cells was not matched by increased apoptosis. The cell cycle inhibitor CDKN1A was increased in both cell lines, but PCNA decreased only in MB cells. Senescence-associated galactosidase beta-1 (GLB1) mRNA was decreased in MCF-7 cells (48 and 72 h) but increased in MB cells (72 h). Increased expression of interleukin-6 (IL-6) and IL-8 was seen in both cell lines, and increased tumor necrosis factor- α was seen at 24 h for MB and 72 h for MCF-7 indicating increased inflammatory responses of the cancer cells. The two breast cancer celllines had different responses to MφCM, mainly involving inhibition rather than stimulation of growth of the cells, stimulation of senescence (MB cells) and increased inflammatory cytokine expression. The estrogen and progesterone receptor status of the cell lines may determine their response to MφCM. The function of the inflammatory cytokines in breast cancer growth remains to be identified.

High-performance graphene oxide/carbon nanotube aerogel-polystyrene (GOCA-PS) composites were successfully prepared. Three-dimensional (3D) GOCA was prepared by self-assembly and a freeze-drying method. The synthesized 3D aerogel has highly porous structure, low density, and good mechanical properties. Then PS was backfilled into the pores of the aerogel by in situ polymerization via vacuum assisted impregnation process to prepared GOCA-PS composites, which has extremely high microhardness (807.4 MPa) and compression modulus (1029.9 MPa) with only 0.41 wt% GO and 0.16 wt% carbon nanotubes.

High molecular weight partially hydrolyzed polyacrylamide (PAM) can be bio-hydrolyzed on the amide side group, however, solid evidence regarding the biological cleavage of its main carbon chain backbone is limited. In this study, viscometry, flow field-flow fractionation multi-angle light scattering (FFF-MALS), and attenuated total reflectance-Fourier transform infrared (ATR-FTIR) analysis were used to investigate the biodegradability of PAM with a nominal molecular weight of 2 × 107 Da (Da) in two suspended aerobic (25 and 40 °C) and two upflow anaerobic blanket reactors (35 and 55 °C) operated for 470 d under a hydraulic residence time (HRT) of 2 d. Both anaerobic and aerobic biological treatment reduced the viscosity from 2.02 cp in the influent to 1.45–1.60 cp, and reduced the molecular weight of PAM using FFF-MALS from 2.17 × 107 Da to less than one-third its original size. The removals of both the amide group and carbon chain backbone in the PAM molecule were further supported by the FTIR analysis. In comparison with the other conditions, thermophilic anaerobic treatment exhibited higher efficiency for PAM biodegradation. Batch test excluded the influence of temperature on the molecular weight of PAM over the range 25–55 °C, suggesting that cleavage of the main carbon chain backbone was attributed to biological degradation. Our results suggested that high molecular weight PAM was biodegradable, but mineralization did not occur.

Macroporous polymers were prepared by mechanically frothing a bio-based epoxy resin and hardener mixture to first create air-in-resin liquid foams, followed by curing of these liquid foams. It was found that heating the air-in-resin liquid foams prior to their gelation decreased the viscosity of the resin mixture and increased the pressure of the air bubbles, leading to an isotropic expansion of the air bubbles. This resulted in an increase in the porosity of the resulting foam-templated macroporous polymers from 71% to 85%. Correspondingly, the compressive moduli ( E ) and strengths ( σ ) of the foam-templated macroporous polymers decreased from 231 MPa and 5.9 MPa, respectively, to 58 MPa and 1.9 MPa, respectively. This decrease is attributed to an increase in the porosity and pore throat frequency of the foam-templated macroporous polymers when heat was applied to the liquid foams. The deformation of the pores based on in situ SEM micro-compression test of the fabricated foam-templated macroporous polymers is also discussed.

Despite the introduction of many novel therapeutics in clinical practice, metastatic renal cell carcinoma (RCC) remains a treatment-resistant cancer. As red and processed meat are considered risk factors for RCC, and a vegetable-rich diet is thought to reduce this risk, research into plant-based therapeutics may provide valuable complementary or alternative therapeutics for the management of RCC. Herein, we present the antiproliferative and antiangiogenic effects of maslinic acid, which occurs naturally in edible plants, particularly in olive fruits, and also in a variety of medicinal plants. Human RCC cell lines (ACHN, Caki-1, and SN12K1), endothelial cells (human umbilical vein endothelial cell line [HUVEC]), and primary cultures of kidney proximal tubular epithelial cells (PTEC) were treated with maslinic acid. Maslinic acid was relatively less toxic to PTEC when compared with RCC under similar experimental conditions. In RCC cell lines, maslinic acid induced a significant reduction in proliferation, proliferating cell nuclear antigen, and colony formation. In HUVEC, maslinic acid induced a significant reduction in capillary tube formation in vitro and vascular endothelial growth factor. This study provides a rationale for incorporating a maslinic acid–rich diet either to reduce the risk of developing kidney cancer or as an adjunct to existing antiangiogenic therapy to improve efficacy.

A broadband vibration energy harvester tailored for self-powered condition monitoring of underground trains is proposed and developed using mechanical non-linearity and integrated multi-mode vibration. A data-driven approach is adopted for harvester design using operational vibration data on a train bogie. The harvester is designed to be unobtrusive while exhibiting good performance in harvesting energy over a wide bandwidth. In this work, the on-site vibration data are first analysed with the design goals identified. Then, a broadband harvester is proposed, implemented and evaluated. The harvester consists of a pre-stretched hosting beam and a group of micro-beams with repulsive magnetic forces on their free ends. A multiple vibration-mode harvester with non-linear dynamics is obtained in such a design. This harvester exhibits good performance over a broad bandwidth in frequency sweep and pseudo-random tests, illustrating its capability in self-powered condition monitoring applications.

The ever-increasing demand for carbon fibre reinforced polymers (CFRP) and stringent environmental legislation have driven the research into recycling and reusing the CFRP waste. This paper presents a mechanical recycling process of CFRP and the application of the recyclates as reinforcement for epoxy foams. The CFRP was mechanically processed using a jet mill. Up to 10 wt% of the CFRP recyclates, without separation of fibre-rich portion and resin-rich portion, was added into epoxy foams. The compressive modulus and strength of the epoxy foams increased from 288 MPa and 7.0 MPa, respectively, to 1060 MPa and 22.8 MPa, respectively, accompanied with an increase in foam density from 0.37 g cm−3 to 0.68 g cm−3. Consequently, the specific compressive modulus and strength (normalised against density) increased from 789 MPa cm3 g−1 and 19.1 MPa cm3 g−1 for unreinforced foam to 1563 MPa cm3 g−1 and 33.5 MPa cm3 g−1 for CFRP recyclates reinforced foam, representing a 98% and 75% improvement, respectively. These results demonstrate that the CFRP recyclates have excellent reinforcing ability for epoxy foams.

Due to the severe restrictions imposed by legislative frameworks, the removal of polyacrylamide (PAM) rapidly and effectively from produced wastewater in offshore oilfields before discharge is becoming an urgent challenge. In this study, a novel advanced oxidation process based on plasma operated in the gas–liquid interface was used to rapidly decompose PAM, and multiple methods including viscometry, flow field-flow fractionation multi-angle light scattering, UV–visible spectroscopy, and attenuated total reflectance-Fourier transform infrared spectroscopy were used to characterize the changes of PAM. Under a discharge voltage of 25 kV and pH 7.0, the PAM concentration decreased from 100 to 0 mg/L within 20 min and the total organic carbon (TOC) decreased from 49.57 to 1.23 mg/L within 240 min, following zero-order reaction kinetics. Even in the presence of background TOC as high as 152.2 mg/L, complete removal of PAM (100 mg/L) was also achieved within 30 min. The biodegradability of PAM improved following plasma treatment for 120 min. Active species (such as O3 and H2O2) were produced in the plasma. Hydroxyl radical was demonstrated to play an important role in the degradation of PAM due to the inhibitory effect observed after the addition of an ·OH scavenger, Na2CO3. Meanwhile, the release of ammonia and nitrate nitrogen confirmed the cleavage of the acylamino group. The results of this study demonstrated that plasma, with its high efficiency and chemical-free features, is a promising technology for the rapid removal of PAM.

Adsorption of Cr(VI) onto different pretreated zeolites modified with cetylpyridinium chloride (CPC) is investigated using batch studies, Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) measurements and scanning electron microscopy (SEM). The results indicate that acidification after alkalization is the most effective pretreatment method, and only alkalization would significantly reduce the sorption capability. This behavior is due to the precipitates, such as CaCO3 and MgCO3, generated after alkalization on zeolite surface interfere the formation of the CPC bilayer, which provides active sites for sorbing Cr(VI). The schematic of the adsorption mechanism is presented. The results indicate that developing a better understanding of the influence of different pretreatments is quite helpful and suggest that the content of Ca/Mg/Fe could be a good indication of the effectiveness of preprocessing.

The tumor microenvironment determines development and progression of many cancers. Epithelial-mesenchymal transition (EMT) is fundamental to tumor progression and metastasis not only by increasing invasiveness but also by increasing resistance to cell death, senescence, and various cancer therapies; determining inflammation and immune surveillance; and conferring stem cell properties. It does this by enabling polarized epithelial cells to transform into cells with a mesenchymal, and therefore motile, phenotype. Tumor-associated macrophages (TAMs) are key cells of the tumor microenvironment that orchestrate the connection between inflammation and cancer. Activation of EMT often requires crosstalk between cancer cells and components of the local tumor microenvironment, including TAMs. In this review, clinical and experimental evidence is presented for control of TAMs in promoting cancer cell invasion and migration and their interaction with the EMT process in the metastatic cascade. The translational significance of these findings is that the signaling pathways that interconnect TAMs and EMT-modified cancer cells may represent promising therapeutic targets for the treatment of tumor metastasis.

The aniline in aqueous solutions is harmful to both human health and the environment. A new synthetic, the templated porous carbon, was designed and studied in this study to adsorb the aniline from aqueous solutions. The templated porous carbon was synthesized by SBA-15 and natural zeolite and characterized by SEM/TEM /FTIR and N 2 sorption/desorption isotherm analysis. The results indicated that the adsorption of aniline followed pseudo-second-order kinetic model and was well fit using the Freundlich isotherm model. The adsorption capacity was influenced by the pore structure and pH. The adsorption–desorption cycles were also investigated in this study, and the results suggested the template-synthesized porous carbon would be a promising adsorbent for the removal of aniline from aqueous solution.

In this work, we show that mechanically anisotropic short carbon fibre (sCF)-reinforced epoxy foams with an isotropic cellular structure can be fabricated from liquid foam templates. Short carbon fibres were mechanically frothed in an uncured liquid epoxy resin to produce an air-in-resin liquid foam template, followed by subsequent polymerisation. Fracture toughness test showed that the incorporation of short carbon fibres into the epoxy foams led to a significant increase in their critical stress intensity factors. It was also observed that neat epoxy foams failed catastrophically whilst sCF-reinforced epoxy foams failed in a progressive manner. Compression test further showed that the in-plane compressive moduli of the mechanically frothed sCF-reinforced epoxy foams were significantly higher than their out-of-plane compressive moduli, signifying an anisotropic mechanical response. This anisotropic mechanical response stemmed from the radial flow generated by the high intensity mechanical frothing process, facilitating the preferential orientation of the added short carbon fibres in-plane whilst the entrained air bubbles during the mechanical frothing process were in equilibrium with the surrounding uncured liquid epoxy resin, resulting in an epoxy foam with an isotropic (spherical) cellular structure.

This study is to discuss the reaction pathways of vanillin (3-methoxy-4-hydroxy-benzaldehyde) degradation by Gordonia sp.The product structure was analyzed by spectroscopic technique. Vanillin removal kinetics could be best described by a simple recalcitrant first order model:-dS/dt=k s,1 X(S-S∞),k s,1 is the vanillin removal rate constant.

Nonporous elastomeric particles are often employed to improve the toughness of brittle epoxy foams but this also decreases their compressive strength and stiffness. Herein, a novel strategy utilizing hollow elastomeric microspheres as toughening agent for epoxy foams is presented. The addition of 0.5 wt.% hollow elastomeric microspheres into epoxy foam leads to a 15% increase in critical stress intensity factor (K1c) to 0.38 MPa m0.5and 33% increase in Charpy impact strength (acU) to 1.05 kJ m−2, respectively, compared to unfilled epoxy foam (K1c = 0.33 MPa m0.5and acU= 0.79 kJ m−2). However, a further increase in the hollow elastomeric microsphere concentration to 1.0 wt.% leads to microsphere agglomeration, which reduces both K1cand acUto 0.35 MPa m0.5and 0.93 kJ m−2, respectively. Nevertheless, the added hollow elastomeric microspheres do not lead to a reduction in the quasi-static compressive properties of the epoxy foams.

Brachyury is an important transcription factor of the T-box gene family with an evolutionarily-conserved function in mesoderm development in the embryo. Recent research has demonstrated that, in various human carcinomas, overexpression of Brachyury is associated with epithelial-mesenchymal transition (EMT), tumor metastasis, expression of markers for cancer stem cells, and resistance to chemotherapy and radiotherapy. Brachyury is a diagnostic and prognostic biomarker, and its expression in tumor tissues is associated with increasing tumor grade, stage, invasiveness, metastasis and poor prognosis. Targeting of Brachyury-positive tumor cells may modulate the extent of EMT and stop invasiveness. Fibroblast growth factor, transforming growth factor-β and other EMT signalling factors are involved in the molecular pathways of Brachyury in tumorigenesis and development. Experimentally, Brachyury knockdown resulted in downregulation of EMT and stem cell markers, formation of tumor spheroids, and invasiveness. Treatment with recombinant yeast-Brachyury vector-based vaccine can activate and expand Brachyury-specific CD4+ and CD8+ T-cells in vitro, with an outcome of lysis of human tumor cells expressing the Brachyury protein. Further understanding of the characteristics of Brachyury and its associated signaling pathways might help in developing novel therapeutic strategies against EMT.