High-Throughput Recognition of Tumor Cells Using Label-Free Elemental Characteristics Based on Interpretable Deep Learning.

With cancer seriously hampering the increasing life expectancy of people, developing an instant diagnostic method has become an urgent objective. In this work, we developed a label-free laser-induced breakdown spectroscopy (LIBS) method for high-throughput recognition of tumor cells. LIBS spectra were straightly collected from cells dropped on a silicon substrate and built into a deep learning model for simultaneous classification of various cancers. To interpret the result of the deep learning algorithm, gradient-weighted class activation mapping was utilized to a one-dimensional convolution neural network (1D-CNN), and the saliency maps thus obtained amplified the differences between the spectra of cell lines. Overall results showed that the 1D-CNN algorithms achieved a mean sensitivity of 94.00%, a mean specificity of 98.47%, and a mean accuracy of 97.56%. Thus, the proposed method performed satisfactorily and is seen as an interpretable classification process for cancer cell lines.

Highly concentrated, ring-shaped phase conversion laser-induced breakdown spectroscopy technology for liquid sample analysis.

A highly concentrated, ring-shaped phase conversion (RSPC) method was developed for liquid sample analysis using the laser-induced breakdown spectroscopy (LIBS) technique. In this work, test samples were prepared by mixing the metal particles with polyvinyl alcohol (PVA) supporter in liquid phase. With heat, the PVA solution solidified inside a modified glass petri dish, forming a metal-enriched polymer ring film. Distinguished from other traditional liquid-to-solid conversing methods, the proposed new method takes advantage of enhanced homogeneity for the target elements inside the ring film. The modified glass petri dish was used to control the ring-shaped concentration. Due to the specially designed circular groove at the bottom of this dish, where the PVA solution and liquid sample mixture accumulated, the target elements were concentrated in this small ring, which is beneficial for enhancing and stabilizing the plasma signals compared to the direct liquid sample analysis using LIBS. The limits of detection for Ag, Cu, Cr, and Ba obtained with the RSPC-LIBS technology were 0.098 µg·mL-1, 0.18 µg·mL-1, 0.83 µg·mL-1, and 0.046 µg·mL-1, respectively, which provided greater improvement than the direct bulk liquid analysis using LIBS.

The L-shape relationship between hemoglobin, albumin, lymphocyte, platelet score and the risk of diabetic retinopathy in the US population.

Background: The primary aim of this study was to investigate the correlation between diabetic retinopathy (DR) and the HALP score (hemoglobin, albumin, lymphocyte, and platelet) in individuals with diabetes within the United States population. Methods: This cross-sectional investigation was based on the National Health and Nutrition Examination Survey (NHANES) database from 2003-2018. The following module calculated the HALP score: HALP score = [lymphocytes (/L) × hemoglobin (g/L) × albumin (g/L)]/platelets (/L). By performing the receiver operating characteristic (ROC) analysis, the optimal cutoff value of HALP was ascertained. Restricted cubic splines (RCS), multivariable logistic regression analysis, sensitivity analysis, and subgroup analysis were conducted to evaluate the effect of the HALP score on DR patients. Finally, the decision curve analysis (DCA) and clinical impact curve (CIC) were conducted to estimate the predictive power and clinical utility of the HALP score with clinical indicators. Results: According to the cutoff value (42.9) determined by the ROC curve, the participants were stratified into a lower HALP group (HALPlow) and a higher HALP group (HALPhigh). An L-shaped relationship between HALP score and DR risk was presented in the RCS model (P for nonlinearity <0.001). The DR risk sharply decreased with the increase of HALP, and the decline reached a plateau when HALP was more than 42.9. After fully adjustment, the multivariate logistic regression analysis found that HALPlow was an independent risk factor for DR (OR = 1.363, 95% CI: 1.111-1.671, P < 0.001). Besides, sensitivity analysis showed consistent results. Furthermore, the combination of HALP score and clinical indicators demonstrated predictive power and clinical utility, as shown by the ROC curve, DCA, and CIC. Conclusion: The HALP score has an L-shaped correlation with the risk of DR, and thus, the HALP score may contribute to the timely intervention of diabetes patients.

Heat-Resistant and Color-Changing Luminescent Polysulfone for Information Encryption and Fire Alarming.

An intrinsic difficulty with thermally responsive photoluminescent materials is that high temperatures usually destroy luminance due to the notorious thermal quenching effect. Limited by the vulnerable chemical structure and soft skeleton, most of the existing photoluminescent responsive materials fail to indicate or work at a surging temperature over 100 °C, thus limiting application in display and alarming in harsh conditions. Herein, enlightened by chameleon's adaptive nature to external stimulus, we introduce a topologically optimized electron donor-acceptor (DA) structure and supramolecular interactions of lanthanide ions into the polymer backbone. The emission color determined by the DA structure is stable at high temperatures, and metal-ligand interaction phosphorescence is temperature-adjustable. Owing to the excellent reproducibility and heat resistance of composite films, the sensors can be bent into different three-dimensional structures and adhered to metal surfaces as flexible thermometers with superior display resolution. The polymer composite film could be directly applied as a photoluminescent quick response (QR) code, with patterns simultaneously variable to a temperature from 30 to 150 °C free of manual operation. More importantly, the polymeric composite could be in-situ-oxidized to a "sulfone" structure with an enhanced glass transition temperature of 297-304 °C. The heat- and flame-resistant characteristics of the oxidized films give rise to the application of fire alarming devices since it can locate the fire source and respond exactly depending on the distance from the fire. The unique display, encryption, and alarming functions of the polymeric composite studied in this work bring forward a new concept of developing a great information security and disaster monitoring system with the application of temperature-responsive materials.

New Strategy for Improvement of Interfacial Interactions between Poly(arylene sulfide sulfone) and Carbon Fiber by Grafting Polymeric Chains via Thiol-Ene Click Chemistry.

A simple and efficient strategy for enhancing the interfacial interaction in carbon fiber-reinforced poly(arylene sulfide sulfone) (CF/PASS) composites by grafting polymeric chains via thiol-ene click chemistry is reported here. Simultaneously, three thiol compounds and carbon nanotubes were grafted on CFs to explore the reaction between the CF and thiol groups. X-ray photoelectron spectroscopy, Raman spectroscopy, and normalized temperature-dependent IR spectroscopy results confirm the successful grafting of three thiol compounds, carbon nanotubes, and polymer chains. Similarly, obvious changes on the CF surface can be seen before and after modification via scanning electron microscopy, such as grafted nanotubes and polymeric resin, and the increase in the modulus gradient and interfacial thickness of CF/PASS can be clearly seen via atomic force microscopy. All the results of micro and macro tests on mechanical properties indicate that connecting low molecular weight thiol-terminated PASS (HS-LPASS) onto CFs enhances the interfacial property and mechanical performance of CF/PASS to a greater extent. The interfacial shear strength, interlaminar shear strength, and tensile strength of CF@HS-LPASS-reinforced PASS (CF@HS-LPASS/PASS) increase significantly by 38.5, 43.6, and 24.4%, respectively. All the results demonstrate that thiol-ene click reactions can be used for CF modification; furthermore, in the presence of external stress, the grafted polymeric interphase can act as a "bridge layer" to improve the stress transfer efficiency.

Improvement and Evaluation of a Device That Determines the Interfacial Shear Strength of Carbon Fiber/Polyphenylene Sulfide Composites.

This study improved homemade apparatus for characterizing the interfacial shear strength (IFSS) of carbon-fiber-reinforced polyphenylene sulfide (PPS/CF) composites. The upgraded generation II experimental device includes a newly developed experimental clamp for samples, as well as testing systems. Compared with the initial generation I apparatus and the commercial Toei instrument, the generation II device is easier and more efficient to operate. The average interfacial adhesion values obtained using these devices were consistently approximately 40 MPa, with relatively low data scatter, showing excellent repeatability and applicability during microbond tests. Notably, the generation II experimental device was equipped with an additional high-frequency data-capturing tool to identify the debonding peak force more precisely, which demonstrated a higher interfacial shear strength of 42.81 MPa during testing. Therefore, the new instrument was able to reflect the change in the interfacial stress state during the interface debonding process more accurately and reliably.

Multilevel structured PASS nanofiber filter with outstanding thermal stability and excellent mechanical property for high-efficiency particulate matter removal.

Particulate matter (PM) pollution from industrialization poses a great threat to people's health. Although fiber-based filters are used effectively to capture PM, the traditional filters with large diameter suffer from low filtration efficiency, high pressure drop and low temperature resistance. In this study, multilayer poly arylene sulfide sulfone (M-PASS) composite filter was designed and fabricated via electrospinning technology. The M-PASS composite filter is sandwich-structure. Due to the unique structure and composition, the M-PASS filter exhibited outstanding removal efficiency of 99.97 ± 0.0050%, extremely low air resistance of 44.3 ± 0.7 Pa, excellent quality factor (QF) of 0.19 ± 0.0019 Pa-1, and desirable mechanical strength of 7.0 ± 0.2 MPa. Furthermore, the as-prepared M-PASS filter can remain outstanding filtration performance at 200.0 â„ƒ due to the high thermal stability of PASS and the removal efficiency was still above 95.2 ± 0.4% after long-term filtration test. These results demonstrate that the structure of filter is the important one for air filtration and the M-PASS nanofiber filters have great potential in PM removal, especially under high temperature conditions.

High-performance filter membrane composed of oxidized Poly (arylene sulfide sulfone) nanofibers for the high-efficiency air filtration.

In this study, a novel, oxidized poly (arylene sulfide sulfone) (O-PASS) nanofibrous membrane filter was successfully fabricated for the effective removal of particulate matter. PASS was electrospun into a nanofibrous membrane with an average nanofiber diameter of 0.31 µm and basis weight of 3 g/m2. These specifications were chosen as they showed high particulate matter removal efficiency (99.98%), low pressure drop (68 Pa), and high quality factor QF (0.125 Pa-1). In addition, the filtration mechanism of the PASS nanofibrous membrane was intuitively revealed by simulating the intercepted particular distributions and motion paths of particles. After a simple oxidation treatment, the O-PASS nanofibrous membrane was successfully built up. The microstructure and morphology showed little change compared with the PASS nanofiber, but the oxidation treatment significantly improved the mechanical properties of the membrane from 1.51 MPa to 4.92 MPa. More importantly, the O-PASS nanofibrous membrane still exhibited high removal efficiency after high temperature, acid, alkali, or organic solvent treatments. Overall, O-PASS nanofibrous membranes are promising high-performance filter materials with high temperature and corrosion resistance.

Fabrication of novel dual thermo- and pH-sensitive poly (N-isopropylacrylamide-N-methylolacrylamide-acrylic acid) electrospun ultrafine fibres for controlled drug release.

Dual temperature- and pH-sensitive materials used as drug carriers have attracted a particularly high level of interest. However, it is limited by low sensitivity to changes in conditions because of large size and low specific surface area. In this work, novel dual temperature- and pH-sensitive poly(N-isopropylacrylamide-N-methylolacrylamide acrylic acid) (PNIPAm-NMA-AAc) ultrafine fibres were successfully prepared by radical copolymerisation, electrospinning and thermal chemical treatment. The PNIPAm-NMA-AAc ultrafine fibres were characterized by Fourier transform infrared (FTIR), proton nuclear magnetic resonance (1H NMR), spectroscopy UV-visible spectroscopy, scanning electron microscopy (SEM) and cell counting kit-8 (CCK-8) assay. The uniformity and small size of PNIPAm-NMA-AAc ultrafine fibres with LCST range from 31 °C to 43 °C were used to drug carrier because of good thermal stability, no cytotoxic. Curcumin as a model drug was well distributed in PNIPAm-NMA-AAc ultrafine fibres. In addition, analysis of curcumin release at different pH values and temperatures confirmed that the PNIPAm-NMA-AAc ultrafine fibres are responsive to both temperature and pH. The maximum amount of curcumin released was 98.47% ±â€¯1.87%. In addition, the release mechanism of curcumin-based PNIPAm-NMA-AAc ultrafine fibres was shown to conform to Fickian diffusion (r2 ≥ 0.95). These results indicated that dual-responsive PNIPAm-NMA-AAc ultrafine fibres are promising as drug carriers.

Segregated poly(arylene sulfide sulfone)/graphene nanoplatelet composites for electromagnetic interference shielding prepared by the partial dissolution method.

Segregated conductive polymer composites have been proved to be outstanding electromagnetic interference shielding (EMI) materials at low filler loadings. However, due to the poor interfacial adhesion between the pure conductive filler layers and segregated polymer granules, the mechanical properties of the segregated composites are usually poor, which limit their application. Herein, a simple and effective approach, the partial dissolution method, has been proposed to fabricate segregated poly(arylene sulfide sulfone) (PASS)/graphene nanoplatelet (GNP) composites with superior EMI shielding effectiveness (SE) and high tensile strength. Morphology examinations revealed that the GNPs were restricted in the dissolved outer layer by the undissolved cores, and there was a strong interaction between the PASS/GNP layer and the pure PASS core. The resultant PASS/GNP composites showed excellent electrical conductivity (60.3 S m-1) and high EMI SE (41 dB) with only 5 wt% GNPs. More notably, the tensile strength of the PASS/GNPs prepared by partial dissolution reached 36.4 MPa, presenting 136% improvement compared to that of the conventional segregated composites prepared by mechanical mixing. The composites also exhibited high resistance to elevated temperatures and chemicals owing to the use of the special engineering polymer PASS as a matrix.

Novel PNIPAm-based electrospun nanofibres used directly as a drug carrier for "on-off" switchable drug release.

Stimuli-responsive smart polymers have been studied extensively. In this work, thermoresponsive poly (N-isopropylacrylamide-N-methylolacrylamide-acrylamide) (PNIPAm-NMA-Am) was successfully synthesised via radical polymerisation, as confirmed by proton nuclear magnetic resonance and fourier transform infrared spectroscopy. PNIPAm-NMA-Am was electrospun into nanofibres, allowing its use as a drug carrier after simple thermal treatment. Thermogravimetric analysis, scanning electron microscopy, and atomic force microscopy results also revealed that the as-prepared PNIPAm-NMA-Am nanofibres have a uniform small diameter, good thermal stability and excellent integrity in aqueous environments. Additionally, the properties of this PNIPAm-NMA-Am nanofibres were tunable with temperature changes below and above the lower critical solution temperature of 48 °C. The drug release properties of PNIPAm-NMA-Am10 nanofibres as a drug carrier were studied via ultraviolet-visible spectroscopy and the results showed that 80% of the drug was released from the nanofibres after six heating and cooling (60-10 °C) cycles within 60 min. Only a small amount of the drug was released during the cooling process, which directly demonstrates "on-off" functionality of PNIPAm-NMA-Am nanofibres for controlled drug release. Finally, cell culture studies indicated that the PNIPAm-NMA-Am nanofibres have not cytotoxicity. Thus, the novel PNIPAm-NMA-Am nanofibres show great potential in the biomedical field as drug carriers.

Release characteristics and processing-structure-performance relationship of electro-spinning curcumin-loaded polyethersulfone based porous ultrafine fibers.

Polymeric porous ultrafine fibers with different structures as drug carrier could be facilely prepared. However, the drug release characteristics and relevant mechanism of different structural porous ultrafine fibers were not well studied. In the present work, different structural Poly-Ether-Sulfone (PES) based porous ultrafine fibers, namely PES, PES/Poly-Ethylene-Glycol (PEG) and PES/Water were prepared by electro-spinning. Curcumin was chosen as drug model loaded in these fibers. Investigation of curcumin release characteristics was carried out by the total immersion in buffer solution. The surface and inner structure of PES based ultrafine fibers were studied by scanning electron microscopy (SEM) in detail. It is found that there is significant difference in the accumulate release amount and release rate with similar structure. About 92.5% of curcumin released within 600 min for PES/PEG ultrafine fibers and only 58.9% of curcumin flowed out from PES with 1000 min. In order to discuss the fact of this phenomenon, the development structure of PES based porous ultrafine fibers was studied with curcumin release. The results indicated that the curcumin release was directly involved with the structure. For PES/PEG, curcumin around the surface layer released in advance. And then, some penetrable structure emerged with PEG dissolving in the buffer solution, which result in larger specific surface area and more embedded curcumin from the interior structure of the ultrafine fibers diffusing out. For the others, curcumin release only through its own pores of ultrafine fibers. Finally, the processing-structure-performance relationship of PES based porous ultrafine fibers were confirmed by the diversity of porosity and contact angle. The research results demonstrate that PES based porous ultrafine fibers have the potential to be used as drug carrier in the drug delivery according to the practical clinical requirements.