Photoelectrochemically active perovskite QDs/TiO2 inverse opal with enhanced photoluminescence intensity.

Photoluminescence intensity of the perovskite QDs coupled with TiO2 was decreased significantly owing to the electron transfer between them. Hererin, the composite of CsPb(Cl0.4Br0.6)3 with TiO2 inverse opal was fabricated and we have proved that the effect of scattering of TiO2 inverse opal layer by layer under the incident excitation light for the enhancement of perovskite QDs photoluminescence intensity is far greater than the decrease of photoluminescence intensity caused by the electron transfer between QDs and TiO2. Particularly, photoelectrochemical characterizations exhibit high charge separation effciency and fast response speed in water. This study opens new possibilities for optoelectronic and photo display applications of perovskites-based NCs.

Controlled preparation of M(Ag, Au)/TiO2 through sulfydryl-assisted method for enhanced photocatalysis.

Here a simple and effective method was explored to fabricate M/TiO2 (M = Ag, Au) composites, which required neither pre-treatment of TiO2 nor any additives as reducing agent. Using amorphous TiO2 spheres functionalized with SH groups as starting materials, the noble metallic ions (Ag, Au) can be adsorbed by TiO2 due to their special affinity with SH groups, which is beneficial to the uniform dispersion of metallic ions on the surface of TiO2. Then the adsorbed ions were reduced to form noble metal nanoparticles by heating process (95 °C) directly without additive as reduction agent. Meanwhile, the amorphous TiO2 was transformed into anatase phase during the heating process. Thus, the transformation of TiO2 along with the reduction of noble metallic ions (Ag, Au) was simultaneously carried out by heating. The XRD patterns proved the formation of anatase TiO2 after heating. The characterizations of XPS and TEM proved the formation of Ag and Au nanoparticles on the surface of TiO2. The element mapping indicated that Ag nanoparticles are dispersed uniformly on the surface of TiO2. The photocatalytic activity of the composites has been investigated by the degradation of methyl orange under visible light irradiation. The results showed that when Ag/TiO2 (2.8 wt%) was used as photocatalyst, about 98% of the MO molecules were degraded in 70 min.

Gender disparities in lung cancer incidence in the United States during 2001-2019.

Lung cancer ranks as one of the top malignancies and the leading cause of cancer death in both males and females in the US. Using a cancer database covering the entire population, this study was to determine the gender disparities in lung cancer incidence during 2001-2019. Cancer patients were obtained from the National Program of Cancer Registries (NPCR) and Surveillance, Epidemiology and End Results (SEER) database. The SEER*Stat software was applied to calculate the age-adjusted incidence rates (AAIR). Temporal changes in lung cancer incidence were analyzed by the Joinpoint software. A total of 4,086,432 patients (53.3% of males) were diagnosed with lung cancer. Among them, 52.1% were 70 years or older, 82.7% non-Hispanic white, 39.7% from the South, and 72.6% non-small cell lung cancer (NSCLC). The AAIR of lung cancer continuously reduced from 91.0 per 100000 to 59.2 in males during the study period, while it increased from 55.0 in 2001 to 56.8 in 2006 in females, then decreased to 48.1 in 2019. The female to male incidence rate ratio of lung cancer continuously increased from 2001 to 2019. Gender disparities were observed among age groups, races, and histological types. In those aged 0-54 years, females had higher overall incidence rates of lung cancer than males in recent years, which was observed in all races (except non-Hispanic black), all regions, and adenocarcinoma and small cell (but not squamous cell). Non-Hispanic black females aged 0-54 years had a faster decline rate than males since 2013. API females demonstrated an increased trend during the study period. Lung cancer incidence continues to decrease with gender disparities among age groups, races, regions, and histological types. Continuous anti-smoking programs plus reduction of related risk factors are necessary to lower lung cancer incidence further.

Experimental Study on Carbon Fiber-Reinforced Composites Cutting with Nanosecond Laser.

The carbon fiber-reinforced composite (CFRP) has the properties of a high specific strength, low density and excellent corrosion resistance; it has been widely used in aerospace and automobile lightweight manufacturing as an important material. To improve the CFRP cutting quality in the manufacturing process, a nanosecond laser with a wavelength of 532 nm was applied to cut holes with a 2-mm-thick CFRP plate by using laser rotational cutting technology. The influence of different parameters on the heat-affected zone, the cutting surface roughness and the hole taper was explored, and the cutting process parameters were optimized. With the optimized cutting parameters, the minimum value of the heat-affected zone, the cutting surface roughness and the hole taper can be obtained, which are 71.7 µm, 2.68 µm and 0.64°, respectively.

A Review of Research Progress on Machining Carbon Fiber-Reinforced Composites with Lasers.

Carbon fiber-reinforced composites are widely used in automobile, aerospace and military lightweight manufacturing due to their excellent mechanical properties such as light weight, excellent fracture resistance, corrosion resistance and wear resistance, etc. However, because of their high hardness, anisotropy and low interlayer strength characteristics, there are many problems with machine carbon fiber-reinforced composites with traditional methods. As a non-contact processing technology, laser machining technology has lots of advantages in carbon fiber-reinforced composites processing. However, there are also some defects produced in laser machining process such the heat affected zone, delamination and fiber extraction due to the great difference of physical properties between the carbon fibers and the resin matrix. To improve the quality of carbon fiber-reinforced composites laser machining, lots of works have been carried out. In this paper, the research progress of carbon fiber-reinforced composites laser machining parameters optimization and numerical simulation was summarized, the characteristics of laser cutting carbon fiber-reinforced composites and cutting quality influence factors were discussed, and the developing trend of the carbon fiber-reinforced composites laser cutting was prospected.

Diagnostic significance of transcranial doppler combined with carotid ultrasound in patients with cerebral ischemic stroke.

OBJECTIVE: To explore the diagnostic value of transcranial doppler (TCD) combined with carotid ultrasound (CU) in cerebral ischemic stroke (CIS). METHODS: A total of 68 patients with CIS who were treated in our hospital from September 2018 to September 2020 were selected as the research group, and another 68 patients with non-CIS admitted during the same period were selected as the reference group. Both groups underwent TCD and CU examinations to compare their diagnostic values. RESULTS: There were no distinct differences concerning clinical data such as gender ratio, age, BMI value, smoking history, residence, and complications between the two groups (P > 0.05). The carotid artery intima-media thickening was reported at a markedly higher rate in the research group compared to the reference group (P < 0.001). It was indicated by the CU examination that the degree of carotid artery stenosis in the research group was more severe compared with the reference group (P < 0.05). The patients in the research group experienced more severe intracranial artery stenosis relative to the reference group by the TCD examination (P < 0.05). The plaque morphology of the research group was predominantly irregular, and the internal echoes were predominantly hypoechoic. The plaque morphology in the reference group was predominantly regular, and the internal echoes were predominantly isoechoic. There was remarkably higher incidence of the research group (78%) with ulcer as compared to the reference group (P < 0.05), and no marked difference was observed in the incidence of calcification (P > 0.05). The combined diagnostic approach was superior to TCD and CUS alone in the terms of accuracy, sensitivity and specificity (P < 0.001). CONCLUSION: TCD combined with CU can greatly improve the diagnostic efficiency of CIS, and provide more evidence for clinical therapy. It deserves promotion and use.

Altered microRNAs in cerebrospinal fluid exosomes in paraneoplastic and autoimmune encephalitis: A possible feedback in cancer development.

AIMS: The purpose of this study was to examine the role of cerebrospinal fluid (CSF) exosomes from patients with paraneoplastic and autoimmune encephalitis (AE). MAIN METHODS: Towards this, microRNA profiling in the exosomes which were isolated from cerebrospinal fluid of 12 patients with anti-N-methyl-d-aspartate (NMDA) receptor encephalitis, 12 patients with anti-gamma-aminobutyric acid-B (GABAB) receptor encephalitis, 12 patients with anti-leucine-rich glioma-inactivated 1 (LGI1) encephalitis, and 12 patients with anti-contactin-associated protein-like 2 (CASPR2) encephalitis, and 12 control individuals negative of antibodies against neuronal auto-antigens. Selected findings were validated with quantitative RT-PCR. DIANA-mirPath was chosen for bioinformatic analysis. KEY FINDINGS: There were ten miRNAs higher expressed in AE patients with anti-NMDAR encephalitis compared to those in healthy controls. Further, eight miRNAs were found to be lower expressed in anti-NMDAR encephalitis CSF derived exosomes. In addition, Endometrial cancer, p53 signaling pathway, Non-small cell lung cancer, Small cell lung cancer, Transcriptional misregulation in cancer, Basal cell carcinoma, Acute myeloid leukemia, Renal cell carcinoma, Colorectal cancer, Choline metabolism in cancer, Melanoma, Pancreatic cancer, Prostate cancer, Ras signaling pathway, Glioma, Pathways in cancer, and Proteoglycans in cancer (all p < 0.01) were significantly enriched in differentially expressed miRNAs. SIGNIFICANCES: Exosomes expressing specific miRNAs in antibody positive AE may participate as a feedback regulation in cancer development.

Exosomes expressing neuronal autoantigens induced immune response in antibody-positive autoimmune encephalitis.

The immunological role of exosomes in autoimmune encephalitis (AE) remains uncharacterized and not examined. In this study we ought to determine whether exosomes are generated in AE and to define the presence of cell surface neuronal autoantigens (autoAgs) in the cargo. Exosomes were isolated from cerebrospinal fluid (CSF) from 12 patients with anti-N-methyl-d-aspartate (NMDA) receptor encephalitis, 8 patients with anti-gamma-aminobutyric acid-B (GABAB) receptor encephalitis, 8 patients with anti-leucine-rich glioma-inactivated 1 (LGI1) encephalitis, 8 patients with anti-contactin-associated protein-like 2 (CASPR2) encephalitis, 10 patients with anti-α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid 1,2 (AMPA) receptor encephalitis and 30 control individuals negative of antibodies against neuronal autoAgs. Western blot demonstrated that CSF or sera derived exosomes from AE contained specific neuronal autoAgs in protein aggregates, however, control subjects had no detectable levels of these neuronal autoAgs. In addition, development of antibodies against NMDAR, GABABR, LGI1, CASPR2, and AMPAR were detected in the sera after 30 days immunization of C57BL/6 J mice with exosomes isolated from antibody positive AE patients; Enzyme-linked immunospot (ELISpot) assay demonstrated increased frequency of neuronal autoAgs-specific IL-17 and IFN-γ in splenocytes from AE derived exosomes immunized mice. We concluded that exosomes expressing neuronal autoAgs were present in CSF from antibody positive AE patients, and we propose these exosomes carrying neuronal autoAgs would play an important role in the immune pathogenesis of autoimmune encephalitis.

Differential Expression of microRNA Profiles and Wnt Signals in Stem Cell-Derived Exosomes During Dopaminergic Neuron Differentiation.

The role of secreted exosomes during dopaminergic (DA) neuron differentiation is still unknown. To investigate the roles of exosomes in DA neuron fate specification, we profiled exosomal microRNAs (miRNAs) during DA neuron differentiation of epiblast-derived stem cells (EpiSCs). There were 26 miRNAs differentially expressed (relative fold >2, p < 0.05) in EpiSC-derived exosomes at 0, 2, 4, 6, 8, 10, 12, and 14 days of DA epiblast differentiation. Among them, 23 exosomic miRNAs were significantly increased, including miR-124, miR-132, miR-133b, miR-218, miR-9, miR-34b, miR-34c, and miR-135a2, while three exosomic miRNAs (miR-214, miR-7a, and miR-302b) were decreased, when compared with control samples. Bioinformatics analysis by DIANA-mirPath demonstrated that extracellular matrix-receptor interaction, signaling pathways regulating pluripotency of stem cells, FoxO signaling pathway, DA synapse, Wnt signaling pathway, GABAergic synapse, and neurotrophin signaling pathway were significantly enriched in DA differentiation-related miRNA signature (all p-values <0.012). Furthermore, messenger RNAs for nine DA neuronal markers tyrosine hydroxylase (TH), Nr4a2, Pitx3, Drd1a, Lmx1a, Lmx1b, Foxa1, Dmrt5, and Slc18a2 were significantly increased expressed over time in exosomes derived from differentiated EpiSCs. Interestingly, adding with exosomes derived from EpiSC induction experiment resulted in a twofold increase of TH-positive neurons production (35% vs. 17%, p < 0.01) during DA neuronal differentiation from mouse embryonic stem cells (ESCs). In summary, our results suggested exosomal miRNAs are potential regulators of DA neuron differentiation. More importantly, EpiSC-derived exosomes could promote the generation of DA neuron differentiation from ESCs.

Design of a water environment monitoring system based on wireless sensor networks.

A water environmental monitoring system based on a wireless sensor network is proposed. It consists of three parts: data monitoring nodes, data base station and remote monitoring center. This system is suitable for the complex and large-scale water environment monitoring, such as for reservoirs, lakes, rivers, swamps, and shallow or deep groundwaters. This paper is devoted to the explanation and illustration for our new water environment monitoring system design. The system had successfully accomplished the online auto-monitoring of the water temperature and pH value environment of an artificial lake. The system's measurement capacity ranges from 0 to 80 °C for water temperature, with an accuracy of ±0.5 °C; from 0 to 14 on pH value, with an accuracy of ±0.05 pH units. Sensors applicable to different water quality scenarios should be installed at the nodes to meet the monitoring demands for a variety of water environments and to obtain different parameters. The monitoring system thus promises broad applicability prospects.

Facile Wearable Vapor/Liquid Amphibious Methanol Sensor.

Detection of methanol is a significant segment for body health and work safety in the production of chemical industry. However, there hardly exists highly selective methanol detection system with green environment for vapor or liquid adaptability, as well as large linear relationship. A facile wearable vapor/liquid amphibious electrochemical sensor for monitoring methanol has been carried out for the first time in this Article. This wearable methanol sensor was fabricated by using a simple screen-printing technology for accomplishing a microdevice platform, showing good linear relationship, high selectivity (multiple volatile chemical compounds), reliable repeatability, good stability, and excellent stretching and bending performance (nitrile glove-based sensor) without pretreatment or adding any polymers into inks. Owing to its good environmental adaptability of vapor or liquid and various sensing behaviors (high sensitivity and wide linear range) by being modified with different content of platinum catalyst, this methanol sensor would have tremendous potential application for environmental monitoring on smart wearable devices when employed based on various platforms (such as PET, cotton, and nitrile gloves).

High binding ability ligand controlled formation of CsPbX3 (X = Cl/Br, Br, I) perovskite nanocrystals with high quantum yields and enhanced stability.

CsPbX3 NCs with both high photoluminescence quantum yields (PLQYs) and enhanced stability have been obtained by using high binding ability ligands. As a result, the CsPbI3 NCs prepared using palmitic acid and oleylamine as ligands have high PLQY (up to 92%), and the PLQYs of CsPbX3 perovskite NCs can be sustained for one month with a slight decrease. Impressively, the presence of palmitic acid and stearic acid can dramatically improve the chemical stability of CsPbX3 NCs. Importantly, 1H NMR measurements indicate that much more palmitic acid remained on the surface of CsPbX3 NCs than oleic acid after purification using solvent, suggesting the higher binding ability of palmitic acid than oleic acid. Finally, the fabricated perovskite NCs were used as luminescent inks and phosphors of white light emitting diodes.

Manipulating Luminescence of Light Emitters by Photonic Crystals.

The modulation of luminescence is essential because unwanted spontaneous-emission modes have a negative effect on the performance of luminescence-based photonic devices. Photonic crystals are promising materials for the control of light emission because of the variation in the local density of optical modes within them. They have been widely investigated for the manipulation of the emission intensity and lifetime of light emitters. Several groups have achieved greatly enhanced emission by depositing emitters on the surface of photonic crystals. Herein, the different modulating effects of photonic crystal dimensions, light-emitter positions, photonic crystal structure type, and the refractive index of photonic crystal building blocks are highlighted, with the aim of evaluating the fundamental principles that determine light propagation. The applications of using photonic crystals to manipulate spontaneous emission in light-emitting diodes and sensors are also reviewed. In addition, potential future challenges and improvements in this field are presented.

Controlled Synthesis of Hollow PbS-TiO2 Hybrid Structures through an Ion Adsorption-Heating Process and their Photocatalytic Activity.

Hollow hybrid nanostructures have received significant attention because of their unique structural features. This study reports a facile ion adsorption-heating method to fabricate hollow PbS-TiO2 hybrid particles. In this method, the TiO2 spheres used as a substrate material to grow PbS are aggregates of many small amorphous TiO2 particles, and each small particle is covered with thioglycolic acid ligands through Ti4+ -carboxyl coordination. When Pb2+ ions are added to a colloidal solution of these TiO2 spheres, these ions are adsorbed by sulfhydryl (-SH) groups to form metal thiolates, and the C-S bond is dissociated by heating to release S2- . The S2- ions react with Pb2+ ions to form PbS without additive sulfur sources. Additionally, the amorphous TiO2 spheres are transformed into the anatase phase during the heating process. As a result, the crystallization of TiO2 spheres along with the formation of PbS is simultaneously carried out by heating. During the heating process, owing to the Kirkendall effect of S2- diffusion and the Ostwald ripening effect of the crystallization of amorphous TiO2 spheres, PbS-TiO2 hollow hybrid structures can be obtained. The XRD and XPS characterizations proved the formation of anatase TiO2 and PbS. The TEM characterization confirmed the formation of hollow structures in the PbS-TiO2 hybrid sample. The photocatalytic activity of the hollow PbS-TiO2 hybrid spheres have been investigated for the degradation of Cr6+ under visible light. The results show that hollow PbS-TiO2 hybrid spheres exhibited the highest photocatalytic activity, in which almost all the Cr6+ was degraded after 140 min.

Monodisperse TiO2 Spheres with High Charge Density and Their Self-Assembly.

Titanium dioxide (TiO2 ) spheres are potential candidates to fabricate three-dimensional (3D) photonic crystals owing to their high refractive index and low absorption in the visible and near-infrared regions. Here, TiO2 spheres with both high surface charge density and uniform size, which are necessary for the self-assembly of TiO2 spheres, have been prepared by means of sol-gel methods in ethanol in the presence of thioglycolic acid as ligand. Thioglycolic acid, which contains two functional groups, not only acts as coordinating ligand for stabilizing and controlling the growth of TiO2 spheres but also endows the resulting TiO2 spheres with high charge density as based on ζ-potential analysis when the pH of the TiO2 aqueous dispersion was 6.5 or higher. The SEM images illustrate that the diameter of the prepared TiO2 spheres can be tuned from 100 to 300 nm by simply controlling the concentration of H2 O. FTIR spectra confirm that thioglycolic acid bonded to the surface of TiO2 spheres through carboxylic groups. As anticipated, the obtained TiO2 spheres could self-assemble to form a 3D opal photonic crystal structure by means of a simple gravity sedimentation method. Then the TiO2 spheres in the 3D opal photonic crystal structure were able to transform into a pure anatase phase by annealing at different temperatures.

Vivid structural colors with low angle dependence from long-range ordered photonic crystal films.

Structural colored materials have attracted increasing attention due to their vivid color effects and non-photobleaching characteristics. However, the angle dependence of these structural colors severely restricts their practical applications, for example, in display and sensing devices. Here, a new strategy for obtaining low angle dependent structural colors is demonstrated by fabricating long-range ordered photonic crystal films. By using spheres with high refractive indices as building blocks, the angle dependence of the obtained colors has been strongly suppressed. Green, golden yellow and red structural colored films with low angle dependence were obtained by using 145 nm, 165 nm and 187 nm Cu2O spheres as building blocks, respectively. SEM images confirmed the long-range highly ordered arrays of the Cu2O photonic crystal films. Reflectance spectra and digital photographs clearly demonstrate the low angle dependence of these structural colors, which is in sharp comparison with the case of polystyrene (PS) and SiO2 photonic crystal films. Furthermore, these structural colors are vivid with high color saturation, not only under black background, but also under white background and natural light without adding any light-absorbing agents. These low angle dependent structural colors endow Cu2O photonic crystal films with great potential in practical applications. Our findings may broaden the strategies for the design and fabrication of angle independent structural colored materials.

Fabrication of Poly(styrene-co-maleic anhydride)@Ag Spheres with High Surface Charge Intensity and their Self-Assembly into Photonic Crystal Films.

Herein, we developed a method to prepare monodisperse poly(styrene-co-maleic anhydride)@Ag (PSMA@Ag) core-shell microspheres with high surface charge intensity by using an in situ reduction method. In this method, ethylenediamine tetraacetic acid tetrasodium salt (Na4EDTA) was used as a reducing agent to promote the growth of Ag, and at the same time endowed the PSMA@Ag spheres with a surface charge. The monodispersity of PSMA and PSMA@Ag and the ordered array of the photonic crystal films were characterized by using SEM. The formation of Ag nanoparticles was confirmed by using TEM, HR-TEM, and XRD characterizations. Due to the existence of surface charges, the obtained PSMA@Ag microspheres easily self-assembled to form photonic crystal structures. In addition, the surface-enhanced Raman scattering (SERS) activity of the PSMA@Ag photonic crystal films was evaluated by detecting the signal from Raman probe molecules, 4-aminothiophenol (4-ATP). The PSMA@Ag photonic crystal films exhibited a high SERS effect, a low detection limit of up to 10-8 for 4-ATP, good uniformity, and reproducibility.