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Sulfur quantum dots (SQDs) are a kind of pure elemental quantum dots, which are considered as potential green nanomaterials because they do not contain heavy metal elements and are friendly to biology and environment. In this paper, SQDs with size around 2 nm were synthesized by a microwave-assisted method using sulfur powder as precursor. The SQDs had the highest emission under the excitation of 380 nm and emit blue fluorescence at 470 nm. In addition, the SQDs had good water solubility and stability. Based on the synthesized SQDs, a fluorescence assay for detection of alkaline phosphatase (ALP) was reported. The fluorescence of the SQDs was initially quenched by Cr (VI). In the presence of ALP, ALP-catalyzed hydrolysis of 2-phospho-L-ascorbic acid to generate ascorbic acid. The generated ascorbic acid can reduce Cr (VI) to Cr (III), thus the fluorescence intensity of SQDs was restored. The assay has good sensitivity and selectivity and was applied to the detection of ALP in serum samples. The interesting properties of SQDs can find a wide range of applications in different sensing and imaging areas. [ABSTRACT FROM AUTHOR]

We have developed a novel biological semiconductor (BSC) based on electrical percolation through a multilayer three-dimensional carbon nanotube--antibody bionanocomposite network, which can measure biological interactions directly and electronically. In electrical percolation, the passage of current through the conductive network is dependent upon the continuity of the network. Molecular interactions, such as binding of antigens to the antibodies, disrupt the network continuity causing increased resistance of the network. A BSC is fabricated by immobilizing a prefunctionalized single-walled carbon nanotubes (SWNTs)--antibody bionanocomposite directly on a poly(methyl methacrylate) (PMMA) surface (also known as plexigiass or acrylic). We used the BSC for direct (label-free) electronic measurements of antibody--antigen binding, showing that, at slightly above the electrical percolation threshold of the network, binding of a specific antigen dramatically increases the electrical resistance. Using anti-staphylococcal enterotoxin B (SEB) IgG as a 'gate' and SEB as an 'actuator', we demonstrated that the BSC was able to detect SEB at concentrations of 1 ng/mL. The new BSCs may permit assembly of multiple sensors on the same chip to create 'biological central processing units (CPUs)' with multiple BSC elements, capable of processing and sorting out information on multiple analytes simultaneously. 10.1021/ac902644z

To analyze the treatment of elderly femoral intertrochanteric fracture (EFIF) using InterTan intramedullary nail (InterTanIN) and proximal femoral nail antirotation (PFNA). A total of 75 patients suffering from EFIF receiving intramedullary fixation were retrospectively collected. According to intramedullary fixation methods, the patients were separated into InterTanIN group and PFNA group. Parameters including the surgery time, blood loss, number of X-ray fluoroscopy, hospital stays, bone-healing time, postoperative Harris hip score (HIS) (1 month, 3 months, 6 months, and 12 months), and complications were collected and analyzed. The results showed surgery time, blood loss, and number of X-ray fluoroscopy in InterTanIN group were higher than those in PFNA group (P < 0.05). The mean hospital stay in the InterTanIN group was comparable to that in the PFNA group (P > 0.05). There was no significant difference in bone-healing time between the InterTanIN group and PFNA group (P > 0.05). The postoperative HIS of InterTanIN group was statistically better than PFNA group at the 3rd month and the 6th month (P < 0.05). With the extension of recovery time, the gap between the two groups gradually narrowed. The postoperative implant displacement happened more often in the PFNA group than in the InterTanIN group. EFIF treated with InterTanIN or PFNA could achieve good long-term efficacy. Although InterTanIN has the disadvantages of increased operative time, blood loss, and radiation exposure compared to PFNA, the postoperative hip function recovery of InterTanIN seems to be more reliable and stable than PFNA. [ABSTRACT FROM AUTHOR]

A silica ring-based ratiometric fluorescence nanosensing and imaging platform was established for the quantification of miRNA-21 with carbon dots and nucleic-functionalized gold nanoparticles inside and outside the ring, respectively. In the presence of miRNA-21, on one hand, the fluorescence emission signal of the originally quenched 6-carboxyfluorescein (FAM), which was labeled on the nucleic acid molecules that modified on the gold nanoparticles, was re-emitted. On the other hand, the fluorescence intensity of the carbon dots inside the ring remained essentially unchanged, which served to eliminate background interference. The ring rather than the shell well maintained the fluorescence of the carbon dots. The ratio of the recovered fluorescence intensity of FAM to the fluorescence intensity of the carbon dots was linearly correlated with the logarithm of miRNA-21 concentration. The linear range of the probe for miRNA detection was more than 3 orders of magnitude, and the detection limit was as low as 2.5 aM. The feasibility of the method for clinical application was verified by the quantitative analysis of intracellular miRNA. [ABSTRACT FROM AUTHOR]

Simple Summary: The clinical outcomes of lung cancer remain poor. The targeted delivery of treatment and the implementation of a method to overcome drug resistance are essential for the improvement of cancer therapy. The aim of our study was to assess the treatment effectiveness of engineered extracellular vesicles (EV) carrying both dinaciclib, a potent CDK inhibitor, and the proapoptotic factor TRAIL for a combinatorial lung cancer therapy. We showed that the engineered complexed EV agent, EV-T-Dina, was stable both in vitro and in vivo. Importantly, EV-T-Dina can overcome the drug-resistance of lung cancer cells, and when nebulized and administered by the pulmonary route, it demonstrated high efficacy and satisfactory safety for the treatment of lung cancers. The underlying mechanism for the synergistic killing of cancer cells by dinaciclib and TRAIL was associated with the concomitant downregulation of the anti-apoptotic factors cFLIP, MCL-1, and Survivin. Thus, the aerosolized EV-T-Dina potentially constitutes a novel and effective therapy for lung cancers. The clinical outcomes of lung cancer remain poor, mainly due to the chemoresistance and low bioavailability of systemically delivered drugs. Therefore, novel therapeutic strategies are urgently needed. The TNF-related apoptosis-inducing ligand (TRAIL)-armed extracellular vesicle (EV-T) has proven to be highly synergistic for the killing of cancer cells with the potent cyclin-dependent kinase (CDK) inhibitor Dinaciclib (Dina). However, both optimal drug formulations and delivery strategies are yet to be established to facilitate the clinical application of the combination of EV-T and Dina. We hypothesize that Dina can be encapsulated into EV-T to produce a complexed formulation, designated EV-T-Dina, which can be nebulized for pulmonary delivery to treat lung cancer with potentially improved efficacy and safety. The prepared EV-T-Dina shows good stability both in vitro and in vivo and is very efficient at killing two highly TRAIL-resistant cancer lines. The ability to overcome TRAIL resistance is associated with the concomitant downregulation of the expression of cFLIP, MCL-1, and Survivin by Dina. The EV-T-Dina solution is nebulized for inhalation, showing unique deposition in animal lungs and importantly it demonstrates a significant suppression of the growth of orthotopic A549 tumors without any detectable adverse side events. In conclusion, the aerosolized EV-T-Dina constitutes a novel therapy, which is highly effective and safe for the treatment of lung cancers. [ABSTRACT FROM AUTHOR]

Nowadays, high-entropy alloys (HEAs) have become a hot research topic in the field of coating materials. However, HEAs have a large wide range of compositional systems, and the differences in their composition inevitably lead to the significant variations in the matching process parameters of laser cladding and post-treatment methods, which in turn give the coatings a broad range of microstructures and protective properties. Therefore, it is crucial to review and summarize the research progresses on laser cladding HEA coatings to provide a reference for obtaining high-performance HEA coatings and further expand the application of HEA coatings. This work describes the working mechanism of laser cladding and illustrates the advantages and drawbacks of laser cladding in detail. The effects of the addition of alloying elements, process parameters and post-treatment techniques on the microstructures and properties of the coatings are thoroughly reviewed and analyzed. In addition, the correlations between the chemical compositions of HEAs, process parameters of laser cladding, post-treatment techniques and the microstructure and protective properties of the coatings are investigated and summarized. On this basis, the future development direction of HEA coatings is outlined. [ABSTRACT FROM AUTHOR]

In recent years, under the pressure of resource shortage and white pollution, the development and utilization of biodegradable wood-plastic composites (WPC) has become one of the hot spots for scholars' research. Here, corn straw fiber (CSF) was chosen to reinforce a poly(lactic acid) (PLA) matrix with a mass ratio of 3:7, and the CSF/PLA composites were obtained by melt mixing. The results showed that the mechanical properties of the corn straw fiber core (CSFC) and corn straw fiber skin (CSFS) loaded PLA composites were stronger than those of the CSFS/PLA composites when the particle size of CSF was low. The tensile strength and bending strength of CSFS/CSFC/PLA are 54.08 MPa and 87.24 MPa, respectively, and the elongation at break is 4.60%. After soaking for 8 hours, the water absorption of CSF/PLA composite reached saturation. When the particle size of CSF is above 80 mesh, the saturated water absorption of the material is kept below 7%, and CSF/PLA composite has good hydrophobicity, which is mainly related to the interfacial compatibility between PLA and CSF. By observing the microstructure of the cross section of the CSF/PLA composite, the research found that the smaller the particle size of CSF, the smoother the cross section of the composite and the more unified the dispersion of CSF in PLA. Therefore, exploring the composites formed by different components of CSF and PLA can not only expand the application range of PLA, but also enhance the application value of CSF in the field of composites. [ABSTRACT FROM AUTHOR]

Common calculation methods of passive earth pressure, such as the Rankine or Coulomb earth pressure theory, assume that the width of the fill behind the wall is sufficient for the development of the slip surface and that after the passive earth pressure reaches the limit state, its value remains unchanged with the increase of displacement of the retaining wall. Nevertheless, cases with narrow backfill width should be considered when retaining walls must be built close to existing stabilization walls in urban areas or near rock faces in mountainous areas. Furthermore, for sand, especially dense sand, when the displacement of the retaining wall is large, a strain-softening behavior similar to the triaxial test will appear, resulting in a decrease in passive earth pressure. In this regard, a practical model for strain-softening of dense sand is proposed firstly and verified by the discrete element method (DEM) using the Particle Flow Code (PFC-2D) software. Then, based on the sliding surface shape obtained by DEM, a simplified method for determining the passive earth pressure distribution of retaining walls using limit equilibrium analysis was proposed. Finally, the passive earth pressures calculated by the proposed method agree well with those from PFC results, and the effects of the width of the backfill and displacement of retaining wall on the distribution of active earth pressure were discussed. [ABSTRACT FROM AUTHOR]

Due to the concurrent prevalence and increasing risk of coinfection of the clinically important Arboviruses, timely and accurate differential diagnosis is important for clinical management and the epidemiological investigation. A two‐tube multiplex real‐time reverse transcription‐polymerase chain reaction (RT‐PCR) assay for the simultaneous detection of Zika virus (ZIKV), chikungunya virus (CHIKV), dengue virus (DENV), yellow fever virus (YFV), West Nile virus (WNV), and Japanese encephalitis virus (JEV) was developed and optimized with high specificity and sensitivity. The detection limit for all the six viruses could reach as low as five genome equivalent copies and 2.8 × 10−3 tissue culture infectious doses (TCID50) for ZIKV, YFV, CHIKV and 2.8 × 10−2 TCID50 for JEV per reaction, with high accuracy and precision (R2 > 0.99). The coefficient of variation of intra‐assay and inter‐assay for our quantitative reverse transcription‐polymerase chain reaction (qRT‐PCR) assay was low, and the obtained positive rates ad Ct values of this assay were comparable with singleplex commercial kits. Moreover, the multiplex qRT‐PCR assay was able to detect possible co‐infections without competitive inhibition of target viral genomes. In conclusion, our rapid, sensitive, cost‐effective multiplex qRT‐PCR will be of great use for differential diagnosis in a clinical setting and epidemiological investigation during surveillance. Highlights: •A two‐tube multiplex quantitative reverse transcription‐polymerase chain reaction (qRT‐PCR) assay for the simultaneous detection of Zika virus, chikungunya virus, dengue virus, yellow fever virus, West Nile virus, and Japanese encephalitis virus was developed and optimized with high specificity and sensitivity.•The multiplex qRT‐PCR assay was able to detect possible coinfections without competitive inhibition of target viral genomes.•This assay will be of great use for the differential diagnosis in clinical setting and epidemiological investigation during surveillance. [ABSTRACT FROM AUTHOR]

Sodium pentachlorophenol (NaPCP) is a highly toxic and persistent organic pollutant. With sepiolite as the support, a series of TiO2-Sep nanocomposites (NCs) with different Ti/Sep ratios were developed. The objective was to understand the effect of Ti/Sep ratio on the structure and activity of the NCs in aqueous and soil systems and to evaluate the feasibility of the NCs for in situ soil remediation. The prepared NCs were characterized with XRD, SEM, TEM, and N2 adsorption–desorption, respectively. The results showed that high surface area and good dispersion of TiO2 on sepiolite surface were obtained. The photocatalytic activities in aqueous and soil of the as-developed NCs were examined using NaPCP as a model pollutant. Compared with bare sepiolite and TiO2, the heterogeneous NCs showed significantly higher photocatalytic performance in decomposing NaPCP, and the photocatalytic activities varied with the content of TiO2 in the NCs. In aqueous media, treatment with TiO2-S-30 showed excellent degradation efficiency with about 90% NaPCP decomposed in 140 min. Nevertheless, the sample TiO2-S-20 promotes maximum rate reduction of NaPCP with above 90% within 20-h irradiation in soil. The results indicate that an appropriate Ti/Sep ratio could significantly enhance the activities of NCs on NaPCP remediation and the role of carrier sepiolite is more important in soil media than that in aqueous phase. The excellent performance of the TiO2-Sep in wastewater degradation and soil remediation can be attributed to the synergistic effects between the high photocatalytic activity of TiO2 nanoparticles and the strong adsorption capacity of sepiolite nanofibers. This work revealed that sepiolite adsorption coupled with TiO2 photocatalysis can be one promising technique for in situ remediation of NaPCP-contaminated soil. [ABSTRACT FROM AUTHOR]

Proton transfer (PT) reactions are fundamental to numerous chemical and biological processes. While sub-picosecond PT involving electronically excited states has been extensively studied, little is known about ultrafast PT triggered by photoionization. Here, we employ femtosecond optical pump-probe spectroscopy and quantum dynamics calculations to investigate the ultrafast proton transfer dynamics of the aqueous phenol radical cation (PhOH˙+). Analysis of the vibrational wave packet dynamics reveals unusually short dephasing times of 0.18 ± 0.02 ps and 0.16 ± 0.02 ps for the PhOH˙+ O–H wag and bend frequencies, respectively, suggestive of ultrafast PT occurring on the ∼0.1 ps timescale. The reduced potential energy surface obtained from ab initio calculations shows that PT is barrierless when it is coupled to the intermolecular hindered translation between PhOH˙+ and the proton-acceptor water molecule. Quantum dynamics calculations yield a lifetime of 193 fs for PhOH˙+, in good agreement with the experimental results and consistent with the PT reaction being mediated by the intermolecular O⋯O stretch. These results suggest that photoionization can be harnessed to produce photoacids that undergo ultrafast PT. In addition, they also show that PT can serve as an ultrafast deactivation channel for limiting the oxidative damage potential of radical cations. [ABSTRACT FROM AUTHOR]

Inconel 718, a nickel-based superalloy, is widely used in the key parts of aero-engine owing to its high performance at elevated temperatures. Meanwhile, Inconel 718 is a typical difficult-to-cut material which is hard to obtain ideal surface integrity by conventional machining (CM). Laser-assisted machining (LAM) has a good potential to improve the machinability. In order to study the processing mechanism in the LAM of Inconel 718, the in-situ and ex-situ studies were presented in this paper. In the in-situ analysis, LAM and CM experiments were carried out based on in-situ observation and digital image correlation (DIC) technology. The Von Mises strain and equivalent plastic strain rate in the primary shear zone (PSZ) and cutting force were measured. According to the DIC results, under the experimental conditions of this paper, the average Von Mises strain and average equivalent plastic strain rate of PSZ in LAM increase by about 10% and 20% respectively due to the softening of Inconel 718 by laser heating, compared with CM. In-situ analysis shows that Inconel 718 in LAM is more prone to plastic flow, resulting in lower cutting forces. As for the ex-situ characterization, the surface roughness, residual stress and tool wear were measured. The measured results show that LAM can significantly reduce surface roughness and tool wear, and cause compressive residual stress on the machined surface. [ABSTRACT FROM AUTHOR]

In the context of ecological building and green building popularity, building sustainability assessment is becoming more and more important. In this paper, a comprehensive evaluation platform by coupled LCA method and energy method was designed, verified, and analyzed to assess the sustainability of the building system. The main results illustrated that the construction stage is the most critical stage in terms of emergy angle. From a sustainability perspective, the Emergy Sustainability Indicator was at a moderate level (1.0141), which can be considered to increase the proportion of renewable energy and reduce the proportion of non-renewable resources to improve the sustainability degree. Of the three scenarios designed, the second scenario has the best sustainability in the building system. The unit emergy value of the whole building was also shown to demonstrate the unit emergy of an individual. In order to verify the accuracy of the data, a sensitivity analysis was conducted. Finally, two types of positive measures are proposed to ameliorate the environmental sustainability in the building system, containing the increasing proportion of renewable energy and using recycled building materials. [ABSTRACT FROM AUTHOR]

Enhanced chemiluminescence (ECL) detection can significantly enhance the sensitivity of immunoassays but often requires expensive and complex detectors. The need for these detectors limits broader use of ECL in immunoassay applications. To make ECL more practical for immunoassays, we utilize a simple cooled charge-coupled device (CCD) detector combined with carbon nanotubes (CNTs) for primary antibody immobilization to develop a simple and portable point-of-care immunosensor. This combination of ECL, CNT, and CCD detector technologies is used to improve the detection of Staphylococcal enterotoxin B (SEB) in food. Anti-SEB primary antibodies were immobilized onto the CNT surface, and the antibody--nanotube mixture was immobilized onto a polycarbonate surface. SEB was then detected by an ELISA assay on the CNT--polycarbonate surface with an ECL assay. SEB in buffer, soy milk, apple juice, and meat baby food was assayed with a LOD of 0.01 ng/mL using our CCD detector, a level sindlar to the detection limit obtained with a fluorometric detector when using the CNTs. This level is far more sensitive than the conventional ELISA, which has a LOD of ~1 ng/mL. Our simple, versatile, and inexpensive point-of-care immunosensor combined with the CNT-ECL immunoassay method described in this work can also be used to simplify and increase sensitivity for many other types of diagnostics and detection assays.

• Generative pre-training network can better do feature embedding of normal pattern. • Anomaly simulation can assist in the learning of one-class classification. • Self-attention-based GCN can enhance the detection of model for logical anomaly. • SLSG achieves SOTA performance and faster speed in detecting comprehensive anomaly. Industrial image anomaly detection under the setting of one-class classification has significant practical value. However, most existing models face challenges in extracting separable feature representations when performing feature embedding and in constructing compact descriptions of normal features when performing one-class classification. One direct consequence is that most models perform poorly in detecting logical anomalies that violate contextual relationships. Focusing on more effective and comprehensive anomaly detection, we propose a network based on self-supervised learning and self-attentive graph convolution (SLSG). SLSG uses a generative pre-training network to assist the encoder in learning the embedding of normal patterns and the reasoning of positional relationships. Subsequently, we introduce pseudo-prior knowledge of anomalies in SLSG using simulated abnormal samples. By comparing the simulated anomalies, SLSG can better summarize the normal patterns and narrow the hypersphere used for one-class classification. In addition, with the construction of a more general graph structure, SLSG comprehensively models the dense and sparse relationships among the elements in an image, which further strengthens the detection of logical anomalies. Extensive experiments on benchmark datasets show that SLSG achieves superior anomaly detection performance, demonstrating the effectiveness of our method. [ABSTRACT FROM AUTHOR]