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Enantioselective recognition and separation have attracted much attention in pharmaceutical analysis, food chemistry, and life science. Herein, we propose an efficient strategy to achieve such purposes using optically active luminogens with aggregation-induced emission (AIE) characteristics. These AIE luminogens (AIEgens) show strong enantiomeric discrimination for 12 kinds of chiral acids and unprotected amino acids. In particular, an exceptionally high enantioselectivity for d/l-Boc-glutamic acid was observed, as demonstrated by the large difference between the formed AIEgen/acid complexes. Due to the AIE effect, enantioselective separation was achieved by aggregation of the AIEgens with one enantiomer in the mixed acid solution. Through analysis of the fluorescence standard curve, the aggregates of AIEgen/chiral acid possessed 90% d-analyte, from which the enantiomeric excess (ee) value was assessed to be 80% ee. Such a result is in good agreement with that (91% d-analyte and 82% ee) by chiral HPLC analysis. Thus, this simple one-step aggregation method can serve as a preliminary screening tool for high-throughput analysis or separation of chiral chemicals.

Photodynamic therapy as a burgeoning and non‐invasive theranostic technique has drawn great attention in the field of antibacterial treatment but often encounters undesired phototoxicity of photosensitizers during systemic circulation. Herein, a supramolecular substitution strategy is proposed for phototherapy of drug‐resistant bacteria and skin flap repair by using macrocyclic p‐sulfonatocalix(4)arene (SC4A) as a host, and two cationic aggregation‐induced emission luminogens (AIEgens), namely TPE‐QAS and TPE‐2QAS, bearing quaternary ammonium group(s) as guests. Through host–guest assembly, the obtained complex exhibits obvious blue fluorescence in the solution due to the restriction of free motion of AIEgens and drastically inhibits efficient type I ROS generation. Then, upon the addition of another guest 4,4′‐benzidine dihydrochloride, TPE‐QAS can be competitively replaced from the cavity of SC4A to restore its pristine ROS efficiency and photoactivity in aqueous solution. The dissociative TPE‐QAS shows a high bacterial binding ability with an efficient treatment for methicillin‐resistant Staphylococcus aureus(MRSA) in dark and light irradiation. Meanwhile, it also exhibits an improved survival rate for MRSA‐infected skin flap transplantation and largely accelerates the healing process. Thus, such cascaded host–guest assembly is an ideal platform for phototheranostics research. Herein, a supramolecular assembly strategy is proposed for phototherapy of drug‐resistant bacteria and skin flap repair by using macrocyclic p‐sulfonatocalix(4)arene as host and two cationic aggregation‐induced emission luminogens bearing quaternary ammonium groups for guests. Such cascaded host–guest assembly is an ideal platform for phototheranostics research.

Hierarchical self-assembly of natural amino acid-derived polymer is an important topic because of its important role in biomimicry, biosensing, and biomedical applications. A recent work published in Nature Communicationsby Mingming Ding and colleagues disclosed that natural amino acid-constructed polyureas can achieve helical and sheet-like conformations upon manipulation of hydrogen bonding by molecular weight and solvent, further confirming fluorescence protein-mimic AIEs and effective intracellular drug release based on the attractive “on-off” switch.

pH values play an important role in various cell biological processes. Abnormal pH values in living systems are frequently associated with the development of diseases such as cancers, infection, and other diseases. Real-time monitoring of the changes of pH values in vivowill give us the significant indication for these diseases’ progression. Within those pH-sensitive imaging probes, aggregation-induced emission (AIE) molecules exhibit great potential in aqueous imaging environment due to their high fluorescence quantum yield and stability. However, the modulation of the AIE probe with pH sensitivity and light-up property face challenges. Here, we introduced a new glycopeptide-modified AIE probe (TGO) based on the optimized solid-phase peptide synthesis approach. The response to pH of the peptide: DDDD progression changed hydrophobicity and hydrophilicity, resulting in the change of the amphipathicity balance. When modulating the pH from 5.5 to 8.0, the adverse protonation of the peptide induced assembled nanostructure transformation from nanolamellae to nanomicelles. Meanwhile, the pH-induced charge change in peptides can greatly influence the microenvironment of the AIEgen, resulting in the increase of fluorescence intensity.

This paper aims at expounding the main subjects widely discussed at the second China International Strength and Conditioning Conference, the theme of which is Leading-edge Theory and Practice in Strength and Conditioning for High Performance Sports, and 16 experts are invited to discuss strength training, speed training, load monitoring, movement function, sport-specific strength and conditioning and the art of coaching etc. Among them, the focus of strength training is on the energy metabolic pathways of soft tissue stiffness training and resistance training for athletes requiring jumping and change of direction. The focus of speed training is on the maximum speed test and training strategy as well as the application of speed data in team sports and strength training. The focus of load monitoring is on the classification of training load and the purpose and significance of monitoring. The movement session mainly discusses the concept and application of functional training. Sport-specific strength and conditioning mainly focuses on the physical fitness training methods for swimming and ice sports. The art of coaching mainly introduces the purpose and application of coaching language. Combined with a literature review by resorting to Ebsco, Ovid and CNKI, this paper summarizes the key points raised at the conference, and is therefore valuable and significant for the reference of research on strength and conditioning training and the practice of strength and conditioning for high performance sports in China. [ABSTRACT FROM AUTHOR]

Dual-state emission (DSE) molecules displayed conspicuous fluorescent performance both in solid and solution states. However, the construction of DSE molecules and the regulation of their emission wavelengths remains a great challenge. Based on the structure-function relationship of quinolinonitrile-type fluorophores, this work proposed a feasible strategy for modulating their fluorescent properties into DSE vialimiting the torsion angle between the quinoline ring and C=C bond in the range of 4.7° to 30°. Based on this strategy, 53 compounds were obtained which displayed tunable emission wavelengths from 397 nm to 740 nm in solid-state and from 360 nm to 672 nm in solution. The feasibility of the strategy was supported by a series of theoretical calculations, optical characterizations, and crystal analysis, suggesting the compounds have great potential in imaging living cells and tissues with desired wavelengths.

Mechanochromic (MC) luminogens in response to external stimulus have shown promising applications as pressure sensors and memory devices. Meanwhile, research on their underlying mechanism is still in the initial stage. Here, three pyridinium-functionalized tetraphenylethylenes bearing n-pentyloxy, hydrogen and nitro groups, namely TPE-OP, TPE-H and TPE-NO, are designed to systematically investigate the influence of the push–pull electronic effect and molecular conformation on MC luminescence. Upon anisotropic grinding and isotropic hydrostatic compression, TPE-OP with strong intramolecular charge transfer (ICT) affords the best MC behavior among them. Analysis of three polymorphs of TPE-H clearly indicates that planarization of the molecular conformation plays an important role in their bathochromic shifts under mechanical stimuli. Theoretical calculations also verify that high twisting stress of AIEgens can be released under high pressure. This study presents a mechanistic insight into MC behaviour and an effective strategy to achieve high-contrast MC luminescence.

Photodynamic therapy (PDT) is a promising noninvasive therapeutic technique and has attracted increasing interests in preclinical trials. However, the translation from laboratory to clinic often encounters the problem of undesired dark cytotoxicity of photosensitizers (PSs). Now, this challenge can be addressed by cascaded substitution activated phototheranostics using the host–guest strategy. Through electrostatical complexation of pyridinium-functionalized tetraphenylethylene, namely, TPE-PHO, and water-soluble calixarene, the dark cytotoxicity of TPE-PHO is dramatically inhibited. The nanoassemblies of the complex show enhanced biocompatibility and selectively locate at the cytoplasm in vitro. When TPE-PHO is competitively displaced from the cavity of calixarene by 4,4′-benzidine dihydrochloride at the tumor site, its dark cytotoxicity and photoactivity in tumor tissue are restored to give efficient PDT efficacy under light irradiation. The result from cell imaging reveals that TPE-PHO undergoes translocation from cytoplasm to mitochondria to kill the cancer cells during the cascaded supramolecular substitution process. In vivo tumor imaging and therapy are successfully implemented to evaluate the curative effect. Such a supramolecular strategy avoids tedious molecular synthesis and opens a new venue to readily tune the PS behaviors.

Colon cancer is one of the most common cancers with high mortality in humans. Early diagnosis and treatment of colon cancer is of great significance for cancer therapy. Numerous theranostic agents have been developed to detect and kill cancer cells. However, few reports have focused on how these agents control and affect the gene expression of cancer cells in vivo. Herein, three pyridinium-functionalized tetraphenylethylene derivatives, namely, TPE-OM, TPE-H, and TPE-NO2, with electron-donating and electron-withdrawing groups were facilely synthesized as theranostic agents for cell imaging and anticolon cancer therapy. Among these AIE luminogens (AIEgens), TPE-OM with donor and acceptor structure showed the best treatment efficacy for colon cancer through systematic biological evaluation and comparison. Both in vitro cell imaging and in vivo tumor treatment experiments demonstrated that TPE-OM can be utilized as an efficient theranostic agent to diagnose and kill colon cancer cells. Flow cytometric analysis revealed that the cell cycle process was disturbed by TPE-OM in colon cancer cells. Deep insight into the gene level revealed that the expressions of cell-cycle-promoting genes was inhibited upon addition of TPE-OM. This study may open a new venue for unraveling the mechanisms of cancer metastasis.

As the important device to perceive the operating state of grid, the condition monitoring device of electric equipment solves such problems as the high rate of false alarm and failure of device caused by the low temperature in winter of cold areas. This paper measures the thermal conductivity of such three kinds of materials as asbestos, rubber and nano porous aerogels in the temperature range of -55°C to +80°C by steady state method, and analyzes the influence of temperature on the thermal conductivity of three materials. According to the result of experiment, the thermal conductivity of nano porous aerogels is the lowest and is affected least by temperature among three kinds of materials. Nano porous aerogels apply to state monitoring device operated in cold areas; and rubber can also be used as thermal insulation material when the operating temperature is generally higher than -20°C.

Chirality is one of the most important features of the nature. The recognition of enantiomers plays significant roles in the field of life science, pharmaceutical analysis and food chemistry. Among various recognition methods, fluorescence spectrometry has attracted much attention of researchers thanks to its high sensitivity and easy operation. Compared with traditional fluorescent probes, chiral molecules with aggregation-induced emission (AIE) have drawn increasing interests due to their huge potential in high-efficiency chemo/biosensors and solid emitters. Chiral AIE luminogens (AIEgens) can not only discriminate two enantiomers with excellent enantioselectivity, but also show general applicability for many chiral analytes, such as chiral acids, amino acids, amines, alcohols. In this review, we mainly summarized the recent development of chiral probes with AIE properties, including chiral tetraphenylethylene (TPE) derivatives, α-cyanostilbene derivatives, Schiff base derivatives and other AIEgens. Their synthetic routes, recognition capabilities and possible working mechanisms were well discussed. It is envisioned that the present review can give some significant guidance for design and synthesis of chiral AIEgens with good enantioselectivity and inspire more readers to join the research of chiral AIE.

Three-dimensional (3D) printed bioactive scaffolds have been widely used in the field of bone tissue engineering. However, its in vivo visualization and bacterial inflammation are intractable issues during the surgery and treatment. Herein, we first synthesized an aggregation-induced emission-active luminogen (AIEgen) named 4BCwith efficient reactive oxygen species (ROS) generation. Then, a series of 3D bioactive scaffolds loaded with 4BCwere fabricated by a precipitation adsorption method, namely 4BC@scaffolds, which showed good in situ imaging performance for the implanted scaffolds by using simple UV light irradiation. Among them, the 4BC@TMP scaffold composed of trimagnesium phosphate (TMP) had excellent bactericidal ability for Escherichia coliand Staphylococcus aureusin vitro and resisted bacterial inflammation in vivo through photodynamic action. H&E and immunofluorescence staining were performed to further evaluate the inhibitory effect of bacterial inflammation in vivo. This work verified that AIEgen-based 3D scaffolds are promising bioactive frameworks for bioimaging and antibacterial applications.

The interface of the ternary boride hard cladding material consists of hard phase (Mo2FeB2) and bonding phase (α-Fe). In this paper, on the basis of the ideal interface model of Mo2FeB2 (100)/α-Fe (001) built with the molecular dynamics software, the Mo2FeB2 (100)/α-Fe (001) interface models with micro-cracks parallel with the interface, normal to the interface, and inclined to the interface have been built separately. The interface bonding energies of these four different interface models have been calculated, which shows that the interface model with the micro crack inclined to the interface has the biggest interface bonding energy, while the interface model with the micro crack parallel with the interface has the smallest bonding energy, the interface crack will be the most easily to propagate. The change rule of bonding energy of the interface model with the micro crack parallel with the interface with different lengths has been simulated and analyzed.

The glass membrane was fabricated by non-solvent-induced phase separation (NIPS) and sintering technique. The preparation process was studied. PVDF was dissolved into DMAc completed. Subsequently, the used glass powder was added into above aqueous solution. The obtained slurry was tape-casted and a green membrane formed. The green membrane was immersed into coagulation bath. The exchange between DMAc and water in coagulation bath took place, and PVDF-containing glass membrane was obtained. The membrane was calcined at different temperature, and the glass membrane was prepared. In order to evaluate the porosity of membrane, many factors including water content in coagulation bath, PVDF content in slurry, coagulation bath temperature and calcination temperature were studied. The viscosity of slurry and shrinkage of membrane after calcination were also studied.

The identification of explosives is critical for analyzing the background of terrorism activities and the origin of pollution aroused by the explosives, but it is a challenge to discriminate the explosives with a very similar structure. Herein we report a series of TPE-based macrocycles with an AIE effect for the 0.2–4 ppb level detection of TNT among a number of nitro-aromatic compounds through fluorescence quenching in natural water sources, whereas the contact mode approach using portable paper sensors exhibited a high sensitivity for the detection of TNT at 1.0 × 10–13M level. The reliability of the quantitative analysis has been confirmed by HPLC. Our findings demonstrate that the TPE-based macrocycles have great potential as excellent sensors for TNT. Moreover, it was found for the first time that the macrocycles could selectively recognize nitroaromatics explosives bearing methyl group through a CH3–π interactions, and even exhibit a sole selectivity for TNT among the very difficultly differentiating nitroaromatics including trinitrophenol and trinitrobenzene.

Indium doped zinc oxide (ZnO:In) films were prepared in oxygen-rich condition by direct current(DC) reactive magnetron sputtering. The X-ray diffraction(XRD) pattern presented that the crystal quality of ZnO:In films was improved by the introduction of nitrogen into ambience, meanwhile the element constituent was investigated by X-Ray photoelectron spectroscopy(XPS). The photoluminescence(PL) spectra showed the visible emission was originated from two different defects. The current-voltage characteristic and persistent photoconductivity(PPC) phenomena were also explained, when the oxygen vacancies(VO) may act trap centers in persistent photoconductivity.

The leaf blade manufacture precision's influencing factors are numerous, and they have coupling relationship each other. So it is difficult to peel out a single factor on the influencing regularity of the blade's machining accuracy. By researching the engine blades of helical milling state under the existing fixture, the leaf blade deformable model based on the instantaneous milling strength was established. Meanwhile, the off-line multi-level error compensation plan was proposed based on the processing surface static error forecasts and compensation. In order to revise the primitive NC tool path code and eliminate the processing distortion inaccuracy, the elastic deformity on each knife position spot is solved on the basis of iterative solution, using the finite element simulation and milling strength model. By using ANSYS finite element simulation, it receives the real-time error compensation of the tool path. And then The experiment has proven the accuracy and the usability of the compensation plan.