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Titanium dioxide/multi-walled carbon nanotubes (TiO2/MWCNTs) are nanocomposites (NCs) prepared via click reaction of TiO2 nanoparticles (TiO2 NPs) with azide groups (TiO2–N3) on the surface and MWCNTs with alkynyl groups (MWCNTs–ALK) on the surface. The phase structure, graphitization degree, structure, elemental composition, the microstructure of TiO2/MWCNTs NCs were characterized by XRD, Raman, IR, XPS and SEM, and their electromagnetic (EM) parameters were determined by the vector network analyser. For TiO2/MWCNTs NCs with click reaction, the minimum reflection loss (RLmin) is up to −47.87 dB at 12.02 GHz, the matching thickness is 2.0 mm, and the bandwidth is lower than −10 dB in the range of 7.7–12.48 GHz. Compared with the physically mixed TiO2/MWCNTs composites, TiO2/MWCNTs NCs prepared by click reaction show more excellent EM absorption properties, which is mainly due to the binding of covalent bonds between the two kinds of materials that lead to the enhancement of interfacial effects, the improvement of impedance matching and the increase of electron migration. [ABSTRACT FROM AUTHOR]

Fe3O4/SiO2 nanocomposites (NCs) were prepared by the interaction of alkyne-functionalized ferric oxide (Fe3O4-Alk) nanoparticles (NPs) and azide-functionalized silicon dioxide (SiO2-N3) NPs via the click reaction. The morphology and structure of the Fe3O4/SiO2 NCs were investigated using scanning electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, and infrared analyses, and the electromagnetic parameters were measured using a vector network analyzer. For the Fe3O4/SiO2 nanocomposites obtained via the click reaction, the minimum reflection loss reached − 37.15 dB at 16.68 GHz and a matching thickness of 5.0 mm, and the bandwidth below − 10 dB ranged from 3.2 to 6.7 GHz and 15.7 to 17.6 GHz. The Fe3O4/SiO2 composites synthesized via the click reaction exhibited better microwave absorption performance than the physically blended sample. This is mainly because Fe3O4 and SiO2 are covalently bonded through the click reaction in the composites, creating multiple heterogeneous interfaces, which enhance dielectric loss and impedance matching. [ABSTRACT FROM AUTHOR]

Tubal inflammation, endometritis, and uterine adhesions due to post-pelvic inflammatory disease (SPID) are important causes of infertility. Chronic endometritis (CE) belongs to SPID, which seriously affects women's reproductive health, quality of life, and family harmony, and is a hot and difficult problem in clinical research. The efficacy of Pen Yan Kang Fu Decoction (PYKFD) has been verified in long-term clinical practice for chronic endometritis infertility caused by the SPID. Numerous studies have confirmed that the LIF/JAK2/STAT3 signaling pathway is important in embryo implantation and development, and endometritis infertility is close to LIF/JAK2/STAT3. In vivo results showed that PYKFD increased endometrial receptivity, repaired uterine tissue damage, and regulates the expression of endometrial receptivity-related factors ER (estrogen receptor), PR (progesterone receptor), CD31, and integrin αvβ3, and induced the transduction of LIF/JAK2/STAT3 signaling pathway. PYKFD can also regulate the expression of IL-6. The results of in vitro experiments showed that PYKFD regulates the behavior of rat endometrial epithelial cells (REECs) involving LIF. In conclusion, PYKFD can improve endometrial receptivity and promote endometrial repair by LIF/JAK2/STAT3 signaling pathway. [ABSTRACT FROM AUTHOR]

This review summarizes and examines research in the area of salpingitis animal modeling in the last 40 years, focusing primarily on Chlamydia trachomatis animal models, which are the most numerous in the literature. Early animal models are examined, followed by a discussion of study parameters and their impact on modeling success, subsequent considerations of fertility measures in modeling, explorations of treatment options, and finally exploring recent directions with a brief discussion of models using other bacterial pathogens. [ABSTRACT FROM AUTHOR]

Enhancing polarization as an effective strategy has attracted wide attention to improve electromagnetic wave absorption performance. In this work, a simple self-template multiple oxidation–etching method is used to prepare the fishing-net-like yolk–shell MnO2@MWCNTs (MYS@MWCNTs) absorber. The structural effects of MYS@MWCNTs and multi-walled carbon nanotube (MWCNTs) dispersion on the microwave absorption properties are investigated in detail. Related SEM and TEM images showed that the MWCNTs disappeared uniformly in MYS@MWCNTs after adjusting the PVP dispersant, thereby weakening the adverse influence of skin effect on impedance matching. One-dimensional MWCNTs penetrated through MnO2 yolk–shell (MYS) microsphere and formed unique fishing-net-like conductive network PVP-optimized MYS@MWCNTs with enhanced impedance matching. MYS@MWCNTs-2 obtains excellent microwave absorption performance with a minimum reflection loss (RLmin) of -52.8 dB at 3.76 GHz because of interface polarization, dipole polarization, and enhanced conductive loss. Therefore, the as-prepared MYS@MWCNTs has potential applications in the field of electromagnetic wave absorption. [ABSTRACT FROM AUTHOR]

In this study, flower sphere alumina was synthesized autonomously by hydrothermal and annealing processes. The in situ polymerization of polypyrrole on the surface of alumina at low temperatures based on the principle of component synergy has enabled the construction of a core–shell structure for Al2O3@ppy materials, resulting in excellent electromagnetic wave absorption properties. The effect of the addition of alumina and the morphology of the materials on the microwave absorption properties of Al2O3@ppy composites was also discussed. Various methods are used for the characterization of the material. The Al2O3@ppy composites were effective in matching thicknesses of 2.5 mm with a minimum reflection loss (RL) of − 65.8 dB at a frequency of 11.52 GHz and a maximum effective absorption bandwidth (EAB) of 5.6 GHz at a matched thickness of 2.0 mm. The results show that Al2O3@ppy composites can provide a reference for EMW absorber material research. [ABSTRACT FROM AUTHOR]

For electromagnetic wave-absorbing materials, organic-derived carbon materials and metal sulfides are highly preferred. In this paper, ZnS/C microsphere composites were prepared using calcination and hydrothermal method. The carbon microsphere material derived from d-xylose was used as a substrate, and zinc sulfide was grown on its surface, thus enhancing the interfacial polarization loss of the material. Considering the defects that originate from within the carbon microspheres and the excellent conductive properties, the composite material involved dipole polarization and conduction losses. These loss mechanisms are coordinated with the optimum impedance match obtained by adjusting the addition of carbon microspheres, resulting in the RLmin value of − 44.86 dB and the EABmax of 5.68 GHz for the ZnS/C microsphere composite. [ABSTRACT FROM AUTHOR]

In this work, we studied the preparation and microwave absorption properties of D-xylose-derived carbon materials modified by CuFe2O4 nanoparticles and discussed the influence of the addition amount of carbon materials. It was prepared with a simple hydrothermal method, and various methods are used to characterize its microscopic morphology, chemical structure and microwave absorption properties.Results show that the modification of copper ferrite nanoparticles is effective in mitigating polarization and magnetic losses, enhancing the microwave absorption properties of the samples and absorption curves of the composite materials change from a single peak to double peaks. Comparing all samples it can be concluded that the effective absorption bandwidth of CuFe2O4 composite materials containing carbon microspheres (CuFe2O4/CMs-0.3) is 6.24 GHz. The minimum reflection loss (RL) is − 50.4 dB at 14.64 GHz. The thickness of the above corresponds to 2.5 mm. This work not only provides a reference method for the preparation of microwave absorbing materials but also contributes to the understanding of absorption mechanisms. [ABSTRACT FROM AUTHOR]

To explore a type of high-performance microwave absorber with lightweight and thin thickness, the flowerlike γ-AlOOH hollow spheres decorated with multi-walled carbon nanotubes (MWCNTs) were fabricated by a facile hydrothermal method. The microscopic morphology characterization showed the γ-AlOOH microspheres consisted of a hollow inner core and a shell made of numerous flakes. The γ-AlOOH/MWCNTs composites exhibited excellent microwave absorption performance with the reflection loss of − 49.8 dB at 11.1 GHz and effective absorption bandwidth of 4.56 GHz (from 13.44 to 18 GHz) at a thickness of 1.5 mm, which covered almost the entire X band. Furthermore, the unique microstructure of γ-AlOOH exerted a considerable effect on the obtained microwave absorption capacity of the composites, leading to interfacial polarization, multiple reflections, and scattering of electromagnetic wave. Meanwhile, the suitable MWCNTs additive amount played a crucial role in the improvement of impedance matching, conduction loss, and dipole polarization, which benefit the performance of microwave absorption. It is expected that the flowerlike hollow spheres structure in our work can provide a method of designing the novel microwave absorbers. [ABSTRACT FROM AUTHOR]

The Al@MnO2 composites were synthesized by flake aluminum powder and potassium permanganate via a facile one-step method. As a multi-band stealth material, the composites have both enhanced microwave absorbing property and low infrared emissivity. We can use XRD, XPS, SEM, and TEM to detect structure and performance, respectively. The microwave absorbing properties and infrared emissivity were investigated by vector network analyzer and dual-band infrared emissometer. It was found that the MnO2 nanoparticles were anchored on the aluminum sheets densely, and the concentration of MnO2 nanoparticles had a certain effect on absorption performance and infrared emissivity. As an absorber, with its polarization effect, resonance effect, and good impedance matching, the composite with the filler loading is 60 wt% can perform excellent microwave absorption performance (Chen et al. in Optik (Stuttg) 172:840–846, 2018). The minimum reflection loss reached − 42.93 dB at 12.72 GHz with a thickness of 1.0 mm, and the bandwidth that exceed − 10 dB ranged from 12.08 GHz to 13.36 GHz (Li et al. in J Colloid Interface Sci 507:131–138, 2017). As an infrared stealth material, the composite exhibits low infrared emissivity in the band range of 8–14 µm, which was attributed to the existence constituent of flake aluminum powder. The infrared emissivity reached 0.55 at the lowest, as well as enlarged with the increase of MnO2 concentration. Therefore, the Al@MnO2 composites could be a potential superior microwave and infrared compatible stealth material. [ABSTRACT FROM AUTHOR]

In this study, two MWCNTs@ZnO/NiO composites, TS-A and TS-B, were synthesized through two methods, respectively, and a series of microscopic morphology characterization and electromagnetic test were performed. Microstructure characterization results suggested that TS-A dispersed well with hierarchical and porous structure, while TS-B grew unevenly as a result of tight bound. Electromagnetic tests show that the unique hierarchical and porous structure was key to the superior absorption performance of TS-A over TS-B, and played an important role in optimizing impedance matching and enhancing dielectric loss. The minimum reflection loss of TS-A reached − 46.65 dB at the thickness of 3.3 mm and the frequency of 3.58 GHz, and the EAB reached 3.89 GHz at the thickness of 1.5 mm. The above results indicate that the synthesis of hierarchical and porous structure is one of the effective ways to enhance the electromagnetic wave absorption ability of materials. [ABSTRACT FROM AUTHOR]

A novel Al@reduced graphene oxide (Al@RGO) composite was designed and synthesized by a one-step hydrothermal method. We investigated the effect of the graphene on the microwave absorbing properties and infrared emissivity of composites. The crystal structure, microscopic morphology, infrared emissivity and electromagnetic parameters of the prepared samples were characterized by XRD, FESEM, TEM, XPS, dual band infrared emissometer and vector network analyzer. TEM and SEM show that the thin Al sheet is uniformly wrapped by RGO with a crumpled surface. Functionalized RGO and surface cation-modified Al sheets are tightly compounded through an electrostatic interaction. The oxygen content and defect from RGO as polarization center endows the material with enhanced molecular polarization and dipole polarization effect. The Al sheet is well coated with RGO, enhancing interface polarization and impedance matching. The minimum reflection loss (RL) of optimized Al@RGO composites is − 46.11 dB at 13.68 GHz under the coating thickness of only 2 mm. The bandwidth below − 10 dB can reach 4.88 GHz (11.52–16.4 GHz). Al sheet is a suitable base material for both microwave absorption and infrared stealth. The Al@RGO composites exhibit excellent infrared stealth ability, and their lowest infrared emissivity is 0.62. Thus, Al@RGO composites show potential application for both electromagnetic wave absorption and infrared stealth. [ABSTRACT FROM AUTHOR]

In this work, Al@MWCNTs (multi-walled carbon nanotubes) composites were prepared by a one-step hydrothermal method. The effects of the morphology and mass ratio of Al@MWCNTs on microwave absorption were studied. The Al@MWCNTs were also found to participate in infrared emissivity. A large number of MWCNTs were interconnected and interspersed between Al sheets, forming a conductive network. As the mass ratio of MWCNTs in the composite was increased, the microwave absorption performance became stronger, and the infrared emissivity remained excellent. When the mass ratio of MWCNTs:Al was 3:20, the minimum reflection loss of the composite at 10.88 GHz was − 39.24 dB, and the effective absorption bandwidth below − 10 dB were 3.04 GHz (9.2–12.24 GHz), the matching thickness was 2 mm, and the infrared emissivity was only 0.67. In this paper, Al powder, a composite material with low infrared emissivity, was creatively used to achieve the superior material bifunctional absorption of MWCNTs, providing a novel and effective way to design other excellent bifunctional materials in the future. [ABSTRACT FROM AUTHOR]

Hexagonal flake Co3O4 was prepared by calcining Co-MOF precursors in air. Co3O4@PANI was obtained via hydrothermal and oxidative polymerization processes, and the electromagnetic wave absorption properties of the composites were investigated. Scanning emission microscopy and transmission electron microscopy images show that hexagonal flake Co3O4 possesses a diameter in the range of 2-4 µm and a side length 550-950 nm. With the decrease in Co3O4 content, the absorption performance of Co3O4@PANI increases gradually. When the mass ratio of Co3O4 to PANI is 1:8, the minimum reflection loss value is − 37.39 dB at 7.28 GHz with a layer thickness of 4 mm. Co3O4@PANI also has effective absorption with the entire test thickness, and the maximum absorption bandwidth can reach 3.52 GHz. Therefore, the as prepared hexagonal flake Co3O4@PANI has potential for application in the field of electromagnetic wave absorption. [ABSTRACT FROM AUTHOR]

Propose: To explore the value of unmeasurable enhancement pattern of residual cavity in predicting survival at early stage after gross-total resection in high-grade glioma (HGG) patients.Methods: This retrospective study enrolled consecutive 51 HGG patients with unmeasurable enhancement who underwent gross-total resection followed by concurrent chemoradiotherapy and adjuvant chemotherapy. We evaluated the enhancement patterns of residual cavity on contrast-T1WI made within 1 month after tumor resection (20 ± 3 days). The survival state of different enhancement was compared.Results: Thin-linear, thick-linear and nodular enhancement were observed in 22 patients (43%), 10 patients (20%), and 19 patients (37%), respectively. The progression-free survival of patients with thin-linear (487, 151-887 days) was longer than those patients with thick-linear (277, 133-573 days), and nodular enhancement (210, 120-765 days) (P = 0.002). The overall survival of patients with thin-linear (774, 457-1343 days) was longer than those with thick-linear (462, 320-678 days), and nodular enhancement (326, 234-1393 days) (P = 0.002). There was no significant difference of orthogonal value between thick-linear and nodular enhancement (0.854), neither between grade III and IV with same enhancement patterns (P = 0.540, P = 0.720).Conclusions: The unmeasurable enhancement patterns in HGG patients within 1 month after gross-total resection, which might be better than the grade of tumor, holds a potential marker in survival state. [ABSTRACT FROM AUTHOR]

SnO/α-FeO@RGO composites were prepared through a solvothermal method. The phase structure, morphology, and electromagnetic (EM)-wave-absorbing properties of the as-prepared samples were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and vector network analyzer. Results indicated that the remarkable EM wave absorption properties of the samples resulted from the interaction between lamella-structured reduced graphene oxide and semiconductor-heterostructured SnO/α-FeO. The optical reflection loss calculated from the measured complex permittivity and permeability was −44.33 dB at 12.64 GHz. Meanwhile, the Fe/Sn molar ratio in the composites was 6:1, and the coating thickness was 2 mm. The bandwidth below −10 dB was 4.4 GHz (10.80-15.20 GHz). Therefore, SnO/α-FeO@RGO could serve as a high-performance EM-wave-absorbing material. [ABSTRACT FROM AUTHOR]

Due to a large surface-to-volume ratio, the optoelectronic performance of lowdimensional semiconductor nanostructure-based photodetectors depends in principle on chemisorption/photodesorption at the exposed surface, but practical examples that show such an effect are still unavailable. Some theoretical calculations have predicted that the {001} facets of InO can effectively accumulate photogenerated holes under irradiation, providing a model material to examine whether the facet cutting of nanowires (NWs) can boost their optoelectronic performance. Herein, we present the design and construction of a novel nanowire-based photodetector using square InO NWs with four exposed {001} crystal facets. The photodetector delivers excellent optoelectronic performance with excellent repeatability, fast response speed, high spectral responsivity ( R ), and high external quantum efficiency (EQE). The R and EQE values are as high as 4.8 × 10 A/W and 1.46 × 10%, respectively, which are larger than those of other popular semiconductor photodetectors. In addition, the square InO NWs show hydrophobic wettability as manifested by a contact angle of 118° and a fast photoinduced reversible switching behavior is observed. [ABSTRACT FROM AUTHOR]

α-FeO/SnO@polyaniline composites were prepared by combining a hydrothermal reaction and an emulsion polymerization process. The sizes of α-FeO and SnO particles dispersed into PANI were 80-120 and 8 nm, respectively. The structure, morphology, and electromagnetic (EM) parameters were characterized by using X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy, and vector network analysis. To achieve the absorption of different EM bands, the EM wave absorption properties of α-FeO/SnO@PANI composites with different stannic oxide content were investigated according to transmission line theory. Polarizations and multiple reflections in the composite absorber play a key role in EM wave absorption. The α-FeO/SnO@PANI composites exhibited high EM absorption capacity and an optimal reflection loss of −50.3 dB at 9.9 GHz with thickness of 2.7 mm. Moreover, the composite could reach an effective absorption bandwidth (below −10 dB) from 7.84 to 12.08 GHz. Thus, the synthesized composites are suitable candidates for highly efficient EM wave absorption in the entire X-band. [ABSTRACT FROM AUTHOR]

Pure KTiO whiskers were prepared by KDC (Kneading-Drying-Calcination) method with TiO and KCO as raw materials. The influences of TiO/KCO molar ratio ( R), calcination temperature ( T) and cooling process on phase composition and morphology of the whiskers were investigated by TG-DSC (thermo gravimetric-differential scanning calorimeter), XRD (X-ray diffraction), and SEM (scanning electron microscope). Pure KTiO potassium titanate whiskers with large length-diameter ratio ( r) (over 250) can be obtained at R = 2.9 and T = 950 °C. [ABSTRACT FROM AUTHOR]

In order to evaluate the prevalence of childhood asthma, allergic diseases and pneumonia in Urumqi City, China, as well as its associations with housing and home characteristics, a cross-sectional study was performed in 4618 children (81.7% response rate, average age 4.7±0.9 year, boys accounting for 53.7%). Questions on children’s asthma and allergic diseases were from the International Study on Asthma and Allergies in Childhood (ISAAC) and were integrated with questions on the home environment from the Dampness in Buildings and Health (DBH) study, slightly modified to account for Chinese building characteristics and life habits. The prevalences of physician diagnosed asthma, allergic rhinitis (AR) and pneumonia were 3.6%, 8.7% and 40.9%, respectively. One fourth of children reported wheezing and more than 40% AR symptoms in the last 12 months. Controlling for confounding factors, positive associations were found for home mold/dampness and wheezing (adjusted odds ratio, aOR 1.33, 95% CI 1.07–1.66), AR symptoms (1.34, 1.09–1.64) last 12 months and physician diagnosed pneumonia (1.33, 1.09–1.62). Floor material by wood, PVC or carpeting; and walls by wallpaper, painting or wood material, were positively associated with AR symptoms. Home environmental tobacco smoke (ETS) was positively associated with wheezing (1.23, 1.04–1.46) and pneumonia (1.25, 1.07–1.45). In conclusion, there was a relatively high prevalence of asthmatic and AR symptoms and diagnosed pneumonia in preschool children in Urumqi. Home signs of mold growth or dampness, windowpane condensation, as well as ETS and interior surface materials emitting chemicals were risk factors for allergic symptoms and pneumonia. [ABSTRACT FROM AUTHOR]

Linear Modulated Frequency (LMF) Costas Stepped Frequency Radar (SFR) signal is introduced. Its ambiguity function is derived and analyzed in detail and its feasibility is validated in theory. The scheme of the proposed signal processing is also presented. The results of theoretic analysis and simulation show that, by using the proposed signal and increasing the bandwidth of the total stepped frequency, the ambiguity sidelobe is well suppressed and the range-velocity coupling in the stepped frequency radar is also greatly weakened. [ABSTRACT FROM AUTHOR]

To study the surface modification of SiC powders with aminoorganosilanes, high solid loading and low viscosity SiC slurry was prepared. Three kinds of aminoorganosilanes were used in the experiment. Infrared Fourier transform spectrometry (Nicolet20SX, America) was applied to analyze the surface characterization of modified SiC powders. The largest solid loading of SiC coated with WD-52 slurry had increased to 54.5vol% and the stabilization also increased remarkably. At the same time, the viscosity of SiC slurry declined. Comparing with WD-50 and WD-57, WD-52 is most effective for modification of SiC powders. [ABSTRACT FROM AUTHOR]

Silica nanoparticles (NP) is one of the most commonly used nanomaterials with potential health hazards. However, the effects of Silica NP on germ cells and the underlying mechanisms are still unclear. In this study, GC-2 and TM-4, which are two different types of male germ cells were exposed to Silica NP for 24h, and then general cytotoxicity and multi-parameter cytotoxicity were evaluated. Our results showed that Silica NP could induce apoptosis in GC-2 cells. Transmission electron microscopy (TEM) results showed that Silica NP was localized in the lysosomes of GC-2 cells. High content screening (HCS) showed that Silica NP exposure could increased cell permeabilization and decreased mitochondrial membrane potential in GC-2 cells. The mRNA and protein levels of apoptosis markers (Bax, Caspase-3, Caspase-9) in GC-2 cells were significantly increased, while Bcl-2 was decreased. Accordingly, the expression level of miR-98, which can regulate Caspase-3, was significantly decreased. Huwe1, the host gene of miR-98, was positively associated with miR-98 expression after Silica NP exposure. Dual luciferase reporter assay suggested that miR-98 directly targets Caspase-3. These results suggest that Silica NP induces apoptosis via loss of mitochondrial membrane potential and Caspase-3 activation, while miR-98 plays key role in modulating this effect. [ABSTRACT FROM AUTHOR]