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CdZnTe (CZT) is a new type of compound semiconductor that has emerged in recent years. Compared to other semiconductor materials, it possesses an ideal bandgap, high density, and high electron mobility, rendering it an excellent room-temperature composite semiconductor material for X-ray and γ-ray detectors. Due to the exceptional performance of CZT material, detectors manufactured using it exhibit high energy resolution, spatial resolution, and detection efficiency. They also have the advantage of operating at room temperature. CZT array detectors, furthermore, demonstrate outstanding spatial detection and three-dimensional imaging capabilities. Researchers worldwide have conducted extensive studies on this subject. This paper, building upon this foundation, provides a comprehensive analysis of CZT crystals and CZT array detectors and summarizes existing research to offer valuable insights for envisioning new detector methodologies. [ABSTRACT FROM AUTHOR]

Background: Tracheal fistulas (TF) can be dangerous and even fatal in patients. The current treatment is really challenging. Previous studies reported that mesenchymal stem cells (MSCs) could be used to treat respiratory tract fistulas. Stem cells from human exfoliated deciduous teeth (SHED) are considered to be MSC-like cells that may also have the potential to treat the tracheal fistulas. In this study, we investigated the therapeutic effects of SHED in rat tracheal fistula models. Methods: A total of 80 SD rats were randomly divided into five groups: a sham-operated group, a local PBS group (L-PBS), an intravenous PBS group (I-PBS), a local SHED treatment group (L-SHED), and an intravenous SHED treatment group (I-SHED). The L-SHED and I-SHED groups were given a topical application around the fistula or an intravenous injection of 1*107 SHED via the tail vein, respectively, while the L-PBS and I-PBS groups were given an equivalent volume of PBS through local or intravenous administration. A stereomicroscope was used to observe fistula healing on the 2nd, 3rd, and 5th days following transplantation. On the 7th day, the survival of SHED was observed by immunofluorescence. The pathology of the lungs and fistulas was observed by hematoxylin and eosin (H&E) and Masson staining. The expression levels of the Toll-like receptor 4 (TLR4), interleukin (IL)-1β, IL-33, and IL-4 were measured using immunohistochemistry. The expression levels of TLR4, high mobility group box 1 (HMGB1), and myeloid differentiation factor 88 (MYD88) were studied using western blotting. On day 14, airway responsiveness of rats was detected and analyzed. Results: Fistula healing in the L-SHED and I-SHED groups was faster than that in their respective PBS groups after transplantation. The fistula diameters in the L-SHED and I-SHED groups were significantly smaller than those in the L-PBS and I-PBS groups on the 3rd day. Moreover, the phenomenon of fibroblast proliferation and new blood vessel growth around the fistula seemed more pronounced in the L-SHED and I-SHED groups. Although no discernible difference was found in airway responsiveness after SHED treatment, the degree of inflammation in the lungs was reduced by intravenous SHED treatment. However, there was no significant reduction in lung inflammation by local SHED treatment. The expression levels of IL-1β and IL-33 were decreased in the I-SHED group, while IL-4 was elevated compared with the I-PBS group. Interestingly, intravenous SHED treatment inhibited the activation of HMGB1/TLR4/MYD88 in the lung tissues of TF rats. Conclusions: SHED transplantation accelerated the rate of fistula healing in rats. Intravenous SHED treatment reduced lung inflammation. Thus, SHED may have potential in the treatment of tracheal fistula, providing hope for future therapeutic development for TF. [ABSTRACT FROM AUTHOR]

Background: Tracheal fistulas (TF) can be dangerous and even fatal in patients. The current treatment is really challenging. Previous studies reported that mesenchymal stem cells (MSCs) could be used to treat respiratory tract fistulas. Stem cells from human exfoliated deciduous teeth (SHED) are considered to be MSC-like cells that may also have the potential to treat the tracheal fistulas. In this study, we investigated the therapeutic effects of SHED in rat tracheal fistula models. Methods: A total of 80 SD rats were randomly divided into five groups: a sham-operated group, a local PBS group (L-PBS), an intravenous PBS group (I-PBS), a local SHED treatment group (L-SHED), and an intravenous SHED treatment group (I-SHED). The L-SHED and I-SHED groups were given a topical application around the fistula or an intravenous injection of 1*107 SHED via the tail vein, respectively, while the L-PBS and I-PBS groups were given an equivalent volume of PBS through local or intravenous administration. A stereomicroscope was used to observe fistula healing on the 2nd, 3rd, and 5th days following transplantation. On the 7th day, the survival of SHED was observed by immunofluorescence. The pathology of the lungs and fistulas was observed by hematoxylin and eosin (H&E) and Masson staining. The expression levels of the Toll-like receptor 4 (TLR4), interleukin (IL)-1β, IL-33, and IL-4 were measured using immunohistochemistry. The expression levels of TLR4, high mobility group box 1 (HMGB1), and myeloid differentiation factor 88 (MYD88) were studied using western blotting. On day 14, airway responsiveness of rats was detected and analyzed. Results: Fistula healing in the L-SHED and I-SHED groups was faster than that in their respective PBS groups after transplantation. The fistula diameters in the L-SHED and I-SHED groups were significantly smaller than those in the L-PBS and I-PBS groups on the 3rd day. Moreover, the phenomenon of fibroblast proliferation and new blood vessel growth around the fistula seemed more pronounced in the L-SHED and I-SHED groups. Although no discernible difference was found in airway responsiveness after SHED treatment, the degree of inflammation in the lungs was reduced by intravenous SHED treatment. However, there was no significant reduction in lung inflammation by local SHED treatment. The expression levels of IL-1β and IL-33 were decreased in the I-SHED group, while IL-4 was elevated compared with the I-PBS group. Interestingly, intravenous SHED treatment inhibited the activation of HMGB1/TLR4/MYD88 in the lung tissues of TF rats. Conclusions: SHED transplantation accelerated the rate of fistula healing in rats. Intravenous SHED treatment reduced lung inflammation. Thus, SHED may have potential in the treatment of tracheal fistula, providing hope for future therapeutic development for TF. [ABSTRACT FROM AUTHOR]

Correction to: Stem Cell Research & Therapy (2022) 13:310 https://doi.org/10.1186/s13287-... Following the publication of the original article [[1]], the authors identified some errors. The therapeutic effect of stem cells from human exfoliated deciduous teeth on a rat model of tracheal fistula. [Extracted from the article]

Rare-earth ions doped fiber lasers at 2 µm can supply various applications in daily life. In this paper, Ho3+/Yb3+ co-doped tellurite glasses were prepared by the high temperature melting method to obtain a strong 2 µm mid-infrared fluorescence emission. The characterization results of the X-ray diffraction (XRD) and differential scanning calorimeter (DSC) show that this glass possesses good crystallization resistance and thermal stability, and its ΔT is 136 °C, which can be successfully drawn. Under the 980 nm LD excitation, strong green (550 nm) and red (660 nm) up-conversion emission were obtained, meanwhile, intensive 2 µm mid-infrared emission was also achieved, and the emission intensity was significantly improved with the increase of Yb3+ concentration, when the Yb3+ content was 2.0, the 2 µm mid-infrared emission intensity was increased by about 28% compared with the content of 0.5, it should be noted that the concentration of Yb3+ is required to be strictly controlled to prevent concentration quenching. In addition, the luminescence process of Ho3+ was further elaborated through the energy transfer mechanism. All results indicate that the Ho3+/Yb3+ co-doped tellurite glass can be an attractive candidate for up-conversion and mid-infrared fiber laser materials. [ABSTRACT FROM AUTHOR]

Yb3 + / Ho3 + co-doped silicate-germanate glasses with excellent thermal properties and optical properties were prepared by a high temperature melting method. The measured parameter ΔT (134°C) >120 ° C indicates that compared with Yb3 + / Ho3 + co-doped germanate glass and Er3 + doped tellurite glass, there is a better crystallization resistance and thermal performance in Yb3 + / Ho3 + co-doped silicate-germanate glass. A 2.0-μm emission with the full-width at half-maximum of 203 nm was successfully obtained when excited by a 980-nm laser diode. Moreover, the results show that doping with an appropriate amount of Yb3 + ions can enhance the 2.0-μm emission intensity significantly. In addition, the underlying mechanism was based on fluorescence spectra. Therefore, the desirable thermal properties and 2.0-μm emission indicate that the Yb3 + / Ho3 + co-doped silicate-germanate glass is a promising candidate for mid-infrared fiber and laser material applications. [ABSTRACT FROM AUTHOR]

Oxyfluoride silicate glasses co-doped with Cr3+ and Yb3+ ions were fabricated in this work. High △T (178–214 °C) value demonstrated that the thermal stability of the prepared glasses were better than tellurite and germanate glasses. X-ray diffraction (XRD) curves proved the amorphous nature of the glasses, the energy dispersive spectroscopy (EDS) analysis and Fourier Transform infrared spectroscopy (FT-IR) curves explored the network structure of glasses. The photoluminescence excitation (PLE) and photoluminescence emission (PL) spectra show that the glasses absorption peaks located at 430 nm (Cr3+:4A 2g - 4T 1g (P)) and 627 nm (Cr3+:4A 2g - 4T 2g), while the emission peak close to 1010 nm (Yb3+:2F 5/2 -2F 7/2), which meets the condition of energy down-conversion. Besides, the energy transfer efficiency (η CET = 33.5%) and the quantum cutting efficiency (η QE = 133.5%) were calculated from the measured decay curves. These values were higher than Cr3+/Yb3+ co-doped fluorosilicate glass with incorporating of CaF 2 (21.5% and 123.5%) and Tb3+/Yb3+ oxyfluoride glass (13.5% and 113.5%), indicating the prepared samples are conducive to the energy transfer from Cr3+ to Yb3+ ions. The experimental results reveal that the oxyfluoride silicate glasses have potential application prospects in crystalline silicon (c-Si) solar cells. [ABSTRACT FROM AUTHOR]

The enhancement of mid-infrared (MIR) fluorescence emission (1800–3000 nm) was achieved by adding Li+ ions into Er3+/Ho3+ co-doped oxyfluoride silicate glass-ceramics containing YF 3 nanocrystals, which was prepared by conventional melt-quenching. The introduction of Li+ ion destroys the glass network [Si–O–Al] structure, and affects the crystallization ability of the substrate glass. In addition, the crystal field effect significantly enhances the up-conversion and MIR fluorescence emission of the prepared samples, with a decay time of 4.6 ms and the maximal absorption cross section (σ abs) of 1.43 × 10−20 cm−2 at 1950 nm, as well as emission cross section (σ em) of 1.73 × 10−20 cm−2 at 2021 nm. The results indicate that the prepared samples have excellent fluorescence properties and can be used for MIR lasers. • Er3+/Ho3+ co-doped silicate glass ceramics containing YF 3 crystals were prepared. • High thermal stability of the prepared samples can resist high energy threshold. • Samples have excellent light absorption and emission capabilities. • Lithium ions improve the mid-infrared and up-conversion emission intensity. [ABSTRACT FROM AUTHOR]

The effect of Li+ ion concentration on mid-infrared (MIR) emission of Ho3+/Er3+ co-doped borosilicate glasses was reported. X-ray diffractometer (XRD) curves confirmed the amorphous structure of the glass. With the introduction of Li+ ions, the [BO 3 ] in the glass network structure was observed to increase while the destruction of [BO 4 ]. The introduction of Li+ ions will make the distance between Er3+ ions and Ho3+ ions in the glass structure closer. The increase of Li+ ions will lead to the polarization of Er3+ ion electron cloud, which is conducive to the energy transfer between Ho3+ and Er3+ as well as the enhanced the emission of 2.0 μm with a full-width at half-maximum (FWHM) of 192 nm. According to the fluorescence decay curve, the energy transfer efficiency of Li+ ion doped sample is up to 80.1%. These above results indicate that the prepared sample is a potential substrate for 2.0 μm MIR lasers. • Er3+/Ho3+ co-doped borosilicate glasses containing Li+ ions were fabricated. • The borosilicate glass possesses good thermal stability. • Li+ ions are beneficial to the mid-infrared fluorescence emission. [ABSTRACT FROM AUTHOR]

Fluorotellurite glasses tri-doped with Tm3+, Er3+ and Bi ions were investigated. The measured parameter ΔT (116 °C) confirmed that the prepared glasses had good stability. An ultra-broadband fluorescence emission (950–1670 nm) was observed with a full-width at half-maximum (FWHM) of 560 nm, which covered the entire bands of O, E, S, C, L and U. The 1800 nm fluorescence intensity of Tm3+/Er3+ co-doped and Tm3+/Er3+/Bi tri-doped glasses was enhanced compared to Tm3+ doped glass, which indicates that there is energy transfer between Tm3+, Er3+ and Bi ions. The maximum fluorescence lifetime of the prepared glasses was 7.39 ms, indicating the excellent fluorescence performance at 1800 nm. Additionally, the maximum absorption cross section (σ abs = 1.77 × 10−20 cm−2) and emission cross section (σ em = 7.61 × 10−20 cm−2) suggest that the Tm3+/Er3+/Bi tri-doped glasses have good optical absorption properties and high gain fluorescence emission. The above results indicate that the Tm3+/Er3+/Bi tri-doped fluorotellurite glasses have good application prospects in the field of fiber amplifiers and near-infrared lasers. [ABSTRACT FROM AUTHOR]

Fe3O4/P(GMA-DVB)/PAMAM/Au microspheres are fabricated to research the catalytic performances to 4-nitrophenol. In the preparation process, Fe3O4 microspheres act as magnetic cores, PAMAM dendrimers growing up on the surface of P(GMA-DVB) polymer work as carriers, and Au nanoparticles serve as catalytic materials. The stability of the prepared microspheres is evaluated by successively catalytic experiments to measure the conversion of 4-nitrophenol, and catalytic efficiency can still maintain up to 78.7% after ten cycles. Moreover, the effects of major factors including the concentration of the prepared microspheres and the temperature of reaction system on the conversion of 4-nitrophenol are also investigated in detail. The manuscript reveals that 4-nitrophenol can be almost converted to 4-aminophenol within 7 min at 45 °C in the case of using 1.0 g/L Fe3O4/P(GMA-DVB)/PAMAM/Au microspheres. Such excellent catalytic properties are ascribed to the optimum structure of the prepared microspheres, which favors the sufficient contact between Au nanoparticles and 4-nitrophenol. The results and strategies exhibited here provide insight into the preparation of sophisticated structures of catalysts to treat wastewater. [ABSTRACT FROM AUTHOR]

Ho3+/Tm3+/Ce3+ tri-doped tellurite glasses with lower phonon energy (761 cm−1) were prepared by melt quenching in this paper. Performing XRD, Raman, DSC performance characterization, it was concluded that the synthetic tellurite glass sample had a multi-element structure, and the ΔT of the prepared tellurite glass was 138 °C, which can be used for fiber drawing with good thermal stability. Under the 808 nm LD excitation, an ultra-broadband emission from 3800 to 4200 nm mid-infrared band with full-width at half-maximum (FWHM) of the prepared glass about 309 nm was achieved, which can be applied to mid-infrared ultra-wide tunable all-fiber laser. With the introduction of CeO 2 , the up-conversion emission were suppressed and strong mid-infrared emission were obtained, at the same time, the fluorescence lifetime of the sample was significantly prolonged, which are mainly due to the cross relaxation between Ho3+ and Ce3+, the energy transfer mechanism was further analyzed through the energy level transition process. The maximum emission cross section and gain coefficient of the tellurite glass were 1.01 × 10−20 cm2 and 1.13 cm−1, which were improved compared with the previously reported tellurite glasses. The results demonstrate that the Ho3+/Tm3+/Ce3+ tri-doped tellurite glass is a promising mid-infrared optical material. • With the introduction of Ce3+ and Tm3+, Ho3+ can achieve ultra-wideband emission between 1800–2200 nm and 3800–4200 nm. • The introduction of Ce3+ greatly enhanced the fluorescence emission of 2 μm, 3.9 μm and 4.1 μm. • Larger absorption and emission cross-sections the glass held, the gain coefficient was also greatly improved. • The fluorescence lifetime at 2 μm and 4.1 μm wavelengths were prolonged with the addition of Ce3+ content. [ABSTRACT FROM AUTHOR]

In this paper, Ho3+, Yb3+ and metal Ag nanoparticles (NPs) tri-doped tellurite glass were synthesized by melt quenching. Combining X-ray diffraction, Raman spectroscopy, and Differential thermal analysis tests, multiple structural units were found in the synthetic glass samples which provided the possibility to achieve high concentration and uniform doping of rare earth ions without degrading the glass forming ability and thermal stability. The fluorescence emission of glasses at 2 μm, 3.9 μm, and 4.1 μm were focused on, as a consequence, the Ho3+/Yb3+/AgNPs tri-doped tellurite glass achieved strong emission at 2 μm, 3.9 μm and 4.1 μm, and the full width at half maximum (FWHM) at 4.1 μm is 316 nm under the 980 nm LD excitation, which realized broadband fluorescence emission. In addition, the fluorescence lifetimes of the glass at 2 μm, 3.9 μm and 4.1 μm are 4.79 ms, 3.81 ms and 4.28 ms meaning the lower laser oscillation threshold the glass holds. It is particularly noteworthy that the emission intensity had been greatly improved about 30% at 2 μm and 27% at 3.9 μm and 4.1 μm with the introduction of AgCl into the matrix, respectively, which was mainly effected by local surface plasmon resonance (LSPR) of AgNPs and the energy transfer between Ag species and Ho3+, whereas the content of AgCl must be strictly controlled to prevent the concentration quenching to decrease the emission intensity. The obtained results demonstrate that Ho3+/Yb3+/AgNPs tri-doped tellurite glass possesses an ideal application prospect on mid-infrared fiber and laser materials. • Strong 3.9 μm and 4.1 μm mid-infrared fluorescence emission are found in tellurite glass. • Larger absorption and emission cross-sections, the gain coefficient is also greatly improved. • Larger FWHM at 4.1 μm is suitable for broadband emission. • The transition of Ho3+ ion energy level in tellurite obtains longer fluorescence lifetime. • The LSPR effect of AgNPs greatly enhances mid-infrared fluorescence emission. [ABSTRACT FROM AUTHOR]