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In this study, the Cr2+ :CdSe and Fe2+ :CdSe crystals were successfully grown by the Mo-crucible sealed Bridgman method using a vacuum single-crystal furnace with two zones developed by ourselves, and the crystal size reaches φ51 mm x 110 mm. Cr2+ :CdSe and Fe2+ :CdSe crystals demonstrate obvious absorption in the bands of 1 400 ~ 2 400 nm and 2 500 ~5 200 nm, respectively. The transmittances of Cr2+/Fe2+ doped CdSe crystals are close to the transmittance limit of CdSe crystal (~70%) in the 7 ~ 15 μm band, and the converted absorption coefficient is about 0.005 cm-1. The Cr2+/Fe2+ : CdSe crystals grown by the Mo-crucible sealed Bridgman method have the advantages of the controllable doping concentration of transition metal ions, uniform doping and high crystal quality. The Cr2+/Fe2+ : CdSe crystals could be used as both midinfrared laser crystal and far-infrared nonlinear optical crystal material. [ABSTRACT FROM AUTHOR]

CdSe crystals are one of the most potential far infrared (IR) nonlinear optical (NLO) materials due to their excellent overall performance. However, it is difficult to prepare a large-size and low absorption CdSe component, which limits laser output power. In this work, a CdSe crystal was grown using a capsuled Mo-crucible method to maintain a stoichiometric melt composition in the process of crystal growth. A high-quality CdSe crystal with the largest size to date of Φ40 × 100 mm3 along the (100) direction was successfully obtained using this method combined with a seed directional technique. The as-grown CdSe crystal demonstrated low absorption coefficients of <0.005 cm−1 at 2.05 μm and 10.6 μm, good crystallinity, and optical homogeneity. An 11 mm × 11 mm × 78 mm CdSe crystal element with = 73.5° ± 0.2°, and ϕ = 0° was fabricated to meet the requirement for type-II phase match (PM), the average idler output power of 1.8 W was obtained corresponding to a pulse energy of ∼0.36 mJ at 10.2 μm using signal-resonate optical parametric oscillator (SR-OPO) technology. Besides, the seed directional technique could provide reference for preparing other NLO crystals, and the capsuled Mo-crucible method could also be used to grow other chalcogenide crystals that have high melting points. [ABSTRACT FROM AUTHOR]

The aim of this paper is to investigate the discrete-time fractional systems from the following aspects. First, the discrete-time fractional unified system in Caputo sense is established with the help of Euler's discretization method. Furthermore, the dynamic behaviors of the discrete-time fractional Lü system (DFLS) which is deemed as a representative for unified system are observed. Then, the correlation dimension ( D 2 ) and Kaplan–Yorke dimension ( D K Y ) of the DFLS are evaluated by the aid of Grassberger–Procaccia algorithm and the Lyapunov exponent spectrum, respectively. Finally, the intrinsic connections between D 2 and D K Y are analyzed by the statistical modeling idea when the DFLS is in chaotic vibrations. The main results show that D 2 shares a positive correlation with D K Y for the chaotic DFLS, while the differences between D 2 and D K Y are not only related to the ratio of the largest and smallest Lyapunov exponents, but also closely tied up with the fractional order v itself. [ABSTRACT FROM AUTHOR]

The Dy3+:PbGa2S4 crystal with low phonon energy has been used to achieve direct lasing of 4.3–4.7 μm lasers. High quality PbGa2S4 crystals are difficult to fabricate due to component volatilization. In this work, the influence of component condition on the intrinsic defects and optical absorption in the Dy3+:PbGa2S4 crystal was investigated through first-principles calculations and crystal growth experiments. We found that PbGa2S4 was prone to decompose into Ga2S3 at its growth temperature, usually resulting in PbS-rich (Ga2S3-deficient) growth conditions. The calculated results of defect formation energy indicate that the PbGa and VGa defects play a dominant role in PbGa2S4 under PbS-rich growth conditions. The Ga2S3-rich growth conditions can increase the defect formation energy and may lower the defect density. Our post-growth annealing and crystal growth experiments proved that the Ga2S3-rich conditions did improve the optical quality of the Dy3+:PbGa2S4 crystal. The structure and composition of PGS were analyzed by XRD and EDS. The XRC result showed the crystal has a high crystalline quality. The changes of bond length were studied through XPS characterization and DFT calculations. The VGa and PbGa defects result in different XPS peaks of PbGa2S4 crystals fabricated under PbS-rich and Ga2S3-rich growth conditions. [ABSTRACT FROM AUTHOR]

• An effective thermal annealing process in In and Zn vapor was performed to improve quality of ZnTe crystals. • The concentration of indium in the annealed crystals is about 4.65 × 1018 cm−3. • The resistivity of annealed ZnTe crystals was enhanced to 109 Ω cm. • The maximum transmittance of annealed ZnTe crystals in the range of 0.5–2 THz can reach up to 70%. In this paper, a large-size and crack-free ZnTe single crystal 40 mm in diameter and 110 mm in length was grown in a two-zone vertical furnace by the modified Bridgman method. To reduce the defect concentration and improve the resistivity of ZnTe crystals for satisfying the requirements in terahertz applications, we investigated an effective thermal annealing process with the first step in Zn vapor at 950 ℃ for 240 h and the second step in In and Zn vapor at 1050/950 ℃(ZnTe/In and Zn) for 120 h. The inductively coupled plasma mass spectrometer (ICP-MS) analysis indicates that the concentration of indium in the annealed crystals is about 4.85 × 1018 cm−3. Compared with the ZnTe crystals annealed in Zn vapor, the X-ray rocking curve (XRC) show that ZnTe crystals annealed in In and Zn vapor still have high crystallization quality. Additionally, the resistivity is enhanced by 5–6 orders to 109 Ω cm while preserving the high infrared (IR) transmittance with about 65 % in the region from 2.5 to 20 μm. The terahertz (THz) transmission spectra of the annealed crystals show higher amplitude, and the maximum transmission is approximately 70 % at the range of 0.5–2 THz, which is 40 % more than the ZnTe crystals annealed in Zn vapor in the low-frequency region. [ABSTRACT FROM AUTHOR]

In this research, the high quality Dy3+, Na+:PbGa 2 S 4 single crystal was grown by Bridgman method. The crystal devices with high transmittance were successfully processed. The crystal structure and crystallization property were characterized by the XRD and XRC patterns. The transmission spectrum, temperature-dependent emission spectrum from 77 K to 350 K and decay curves at room temperature of crystal were measured. The strong absorption at 1315 nm of 6H 15/2 → 6F 11/2 +6H 9/2 transition could match well with high power 1310 nm semiconductor laser. The spectroscopic parameters were calculated by Judd-Ofelt theory based on the absorption spectra. The fluorescence lifetime of 6H 11/2 energy level was fitted to be 2.09 ms and the corresponding fluorescence quantum efficiency η was calculated to be 77%. The emission cross-section at 4325 nm of 6H 11/2 → 6H 13/2 transition was also calculated to be 0.9 × 10−20 cm2. The experiment results show the advantage of Dy3+, Na+:PbGa 2 S 4 crystal in emitting mid-infrared lasers. • High-quality Dy3+,Na+: PbGa 2 S 4 crystal devices were prepared using pressure-resisted and crucible-capsule Brigdman technique 3. • The spectroscopic parameters of Dy3+,Na+: PbGa 2 S 4 were calculated in detail by J-O theory. • The fluorescence emission spectrum and lifetime of Dy3+,Na+: PbGa 2 S 4 crystal at 4325 nm were measured. [ABSTRACT FROM AUTHOR]

Objective. To investigate the epidemiologic and etiologic factors, clinical features, therapeutic regimen, and prognosis of crayfish-related rhabdomyolysis (Haff disease). Methods. Retrospectively analyzed the clinical data of 29 patients with crayfish-related rhabdomyolysis (Haff disease) from July to August 2016, summarized the clinical characteristics, and evaluated the prognosis. Results. Clinical data of a total of 29 cases of Haff disease were retrospectively analyzed. The disease onset occurred after consumption of cooked crayfish with the incubation period ranging from 1 h to 48 h. There were no gender differences and significantly elevated CK in the duration with peak value of 41575.0U/L; the median value was 2445.0U/L (range: from 1187.0 U/L to 4722.0 U/L) and there was coincident elevated CK-MB. There was also no hepatorenal damage and transient urinalysis was abnormal. The most common presenting symptoms were myalgia (100%), weakness and numbness (51.7%), chest tightness and chest pain (41.4%), back pain (41.4%), and extremities pain (37.9%). All the patients recovered and no patients died. Conclusions. Crayfish-related rhabdomyolysis (Haff disease) is a kind of a case or cluster of patients present with severe myalgia or weakness of unknown etiology and mechanism disease; however, the clinical signs and symptoms are relatively mild with favorable outcome. [ABSTRACT FROM AUTHOR]

The pnictide and chalcogenide semiconductors are promising materials for the applications in the field of photoelectric. High-purity and high-volume polycrystalline required in the real-world applications is hard to be synthesized due to the high vapor pressure of phosphorus and sulfur components at high temperature. A new high-pressure-resisted method was used to investigate the synthesis of the nonlinear-optical semiconductor ZnGeP 2 . The high-purity ZnGeP 2 polycrystalline material of approximately 500 g was synthesized in one run, which enables the preparation of nominally stoichiometric material. Since increasing internal pressure resistance of quartz crucible and reducing the reaction space, the high-pressure-resisted method can be used to rapidly synthesize other pnictide and chalcogenide semiconductors and control the components ratio. [ABSTRACT FROM AUTHOR]

Paraquat (PQ) is a potent toxicant for humans, and poisoning with PQ is associated with high mortality. Patients with severe PQ-induced poisoning may die of multiple organ failure involving the circulatory and respiratory systems. Death resulting from epilepsy-like convulsions, which are infrequently noted reported with PQ poisoning, is observed clinically with this condition. This study presents the clinical data of five patients with severe PQ-induced poisoning who died of epilepsy-like convulsions, and related publications were reviewed in order to investigate the pathogenesis, clinical manifestations, and prognosis of these convulsions. Our results may help prevent this event and improve the success of treatment. [ABSTRACT FROM PUBLISHER]

Objective. To examine the utility of arterial blood gas analysis (ABG) in early evaluation of prognosis in paraquat poisoning. Methods. Our aim was to summarize the case data of 138 patients poisoned with oral paraquat treated in the Emergency Department of 307 Hospital of the Chinese People's Liberation Army from June 2009 to Sept. 2010, and analyze the correlations between various indices of arterial blood gas analysis (including pH, PO2, PCO2, base excess [BE], HCO3−) to prognosis and blood PQ concentration of patients presenting within 24 h after taking paraquat. Results. PCO2, HCO3− and BE values in deceased patients were significantly lower than those in surviving patients, p values 0.0003, <0.0001, <0.0001; PCO2, HCO3− and BE values in patients who died in < 3 d were significantly lower than those in those who died in 3-7 d and 7 d after taking paraquat (p < 0.0001). The results of Cox Regression Analysis showed that there was correlation between paraquat amount, blood paraquat concentration and BE values and patients' survival time; the larger the absolute BE value was, the higher the death rate. Nevertheless, there were no correlations between early pH or PO2 and prognosis in these patients. Conclusion. BE values may be a reliable index in early evaluation of prognosis in paraquat poisoning. [ABSTRACT FROM AUTHOR]

Terbium gallium garnet (Tb3Ga5O12, TGG) is widely investigated due to its multifunctional applications. However, the electronic structure, optical dispersion properties, bandgap and luminescence mechanisms of the TGG crystal are still not reported. In this study, density functional theory (DFT) calculations were performed to investigate the electronic structure of TGG. The TGG single crystal was grown by the Czochralski method, and its dispersive refractive index, transmission spectrum and photoluminescence spectrum were measured. The first-principles calculation indicates that some of the 4fn configuration component of Tb3+ was mixed into the conduction band, and some component of the 5d state was mixed into 4f state in the gap of TGG, which partially removed the parity forbidden rule, and resulted in the 5D4 → 4FJ optical transition. The Wemple DiDomenico (WDD) model was employed to fit the measured refractive indices, which gave its dispersion energy and optical bandgap. The bandgap of TGG was determined as equal to 3.83 eV, 3.76 eV and 3.85 eV by the DFT model, WDD model and Tauc's plot, respectively. [ABSTRACT FROM AUTHOR]

Background: Paraquat (PQ) is a widely used and highly toxic herbicide that poses a significant risk to human health. The main consequence of PQ poisoning is pulmonary fibrosis, which can result in respiratory failure and potentially death. Our research aims to uncover a crucial mechanism in which PQ poisoning induces senescence in epithelial cells, ultimately regulating the activation of pulmonary fibroblasts through the exosomal pathway. Methods: Cellular senescence was determined by immunohistochemistry and SA-β-Gal staining. The expression of miRNAs was measured by qPCR. Pulmonary fibroblasts treated with specific siRNA of SIRT1 or LV-SIRT1 were used to analysis senescent exosomes-mediated fibroblasts activation. Luciferase reporter assay and western blot were performed to elucidated the underlying molecular mechanisms. The effects of miR-217-5p antagomir on pulmonary fibrosis were assessed in PQ-poisoned mice models. Results: Impairing the secretion of exosomes effectively mitigates the harmful effects of senescent epithelial cells on pulmonary fibroblasts, offering protection against PQ-induced pulmonary fibrosis in mice. Additionally, we have identified a remarkable elevation of miR-217-5p expression in the exosomes of PQ-treated epithelial cells, which specifically contributes to fibroblasts activation via targeted inhibition of SIRT1, a protein involved in cellular stress response. Remarkably, suppression of miR-217-5p effectively impaired senescent epithelial cells-induced fibroblasts activation. Further investigation has revealed that miR-217-5p attenuated SIRT1 expression and subsequently resulted in enhanced acetylation of β-catenin and Wnt signaling activation. Conclusion: These findings highlight a potential strategy for the treatment of pulmonary fibrosis induced by PQ poisoning. Disrupting the communication between senescent epithelial cells and pulmonary fibroblasts, particularly by targeting the miR-217-5p/SIRT1/β-catenin axis, may be able to alleviate the effects of PQ poisoning on the lungs. [ABSTRACT FROM AUTHOR]

Long-term exposure to cadmium-polluted environments may lead to shortened leukocyte telomere length and cognitive decline. This study aims to investigate (1) the associations among blood cadmium levels, leukocyte telomere length, and cognitive function, and (2) the mediating role of leukocyte telomere length between blood cadmium levels and cognitive function among older adults in the United States. Using data from the National Health and Nutrition Examination Survey (NHANES) 1999–2002. Cadmium exposure level was assessed by measuring cadmium levels in blood samples. Leukocyte telomere length was measured by quantitative polymerase chain reaction, and cognitive function was measured by the digit symbol substitution test (DSST). A total of 2185 older adults aged over 60 were included in this study, comprising 1109 (49.65%) males. Elevated blood cadmium levels were significantly associated with the risk of a decline in cognitive function (β = - 2.842, p = 0.018). Shorter leukocyte telomere lengths were significantly associated with a higher risk of a decline in cognitive function (β = 4.144, p = 0.020). The total indirect effect on the blood cadmium level and cognitive function via leukocyte telomere length was - 0.218 (p = 0.012). The mediation effect was estimated to be 0.218/2.084 × 100% = 10.46%. The findings suggest that cadmium exposure may increase the risk of cognitive impairment by causing shortened leukocyte telomere length. [ABSTRACT FROM AUTHOR]

Owing to the large x-ray attenuation coefficient, appropriate bandgap, high resistivity, and high mobility-lifetime (μτ) product, binary II–VI semiconductor CdSe is a promising x-ray detection material and it has exhibited excellent x-ray detection at room temperature (RT). For further improving the characteristics of CdSe x-ray detectors, the electrical properties of CdSe single crystals (SCs) grown through the pressure-assisted vertical Bridgman method and their x-ray detection performance have been investigated at RT and liquid nitrogen temperature (LNT), respectively. The significantly enhanced x-ray photocurrent and the prolonged response time of the devices operating at LNT indicate the photogenerated carrier lifetime could be increased by the enhanced trapping–detrapping effect obviously, and the μτ product of CdSe SCs increases from 1.39 × 10−5 to 5.34 × 10−4 cm2 V−1 with temperature lowering from RT to LNT. Meanwhile, an ultrahigh sensitivity of 5.24 × 106μC Gyair−1 cm−2 and an extremely low detection limit of 3.68 nGyair s−1 have been acquired by the CdSe SC based x-ray detectors at LNT, which is 140 times higher and 5.8 times lower than it has been at RT. Compared with conventional semiconductor x-ray detectors, the ultra-high sensitivity and extremely low detection limit of CdSe SC based detectors make their application prospects very promising. [ABSTRACT FROM AUTHOR]

Abstract: High quality nonlinear infrared crystal material GaSe was grown using a seed aided Bridgman–Stockbarger method having a size of 24–26mm in diameter and 55–70mm in length. The crystals were characterized using X-ray diffraction, electron energy scattering, transmission spectrophotometry and infrared microscopy. The transmission spectrum showed that the infrared transmission is about 67% in an 8mm thick sample cleaved along (001) face, and mean absorption 0.01–0.08cm−1 in the range 0.9–15μm. It may be suitable for the fabrication of infrared nonlinear optical devices, photoelectric analyzers of polarized light and so on. Crystals grown by this method with the described procedures may also be useful for other similar layered compounds. [Copyright &y& Elsevier]

• PQ induces myofibroblasts differentiation of lung epithelial cells and fibroblasts to promote pulmonary fibrosis. • PQ activates Wnt/β-catenin signaling pathway in pulmonary fibrogenesis. • DKK1 suppresses the myofibroblasts differentiation and ameliorates pulmonary fibrosis via inhibiting Wnt/β-catenin signaling. Paraquat (PQ) poisoning-induced pulmonary fibrosis always results in fatal harm to patients. Our study aimed to investigate the functions of the Wnt/β-catenin pathway in PQ-induced pulmonary fibrosis. By comparing the proteomic profiles of rat lung tissues using protein array in the absence or presence of PQ, the Wnt/β-catenin signaling, as a fibrosis-related pathway, was discovered to be profoundly activated by PQ. The protein levels of Wnt/β-catenin signaling components including MMP-2, β-catenin, Wnt3a, Wnt10b, Cyclin D1, and WISP1 were increased in PQ-treated rat lung tissues. Surprisingly, PQ was found to be able to promote lung epithelial cells and fibroblasts differentiating into myofibroblasts by activating Wnt/β-catenin signaling pathway. Dickkopf-1 (DKK1), an antagonist of Wnt/β-catenin signaling pathway, could inhibit the myofibroblast differentiation and attenuate PQ-induced pulmonary fibrogenesis in vitro and in vivo. The expression levels of fibroblasts markers Vimentin, α-smooth muscle actin (α-SMA) and Collagen I was detected and found to be increased when PQ treated and restored with additional DKK1 treatment. In summary, these assays indicated that Wnt/β-catenin signaling pathway played a regulatory role in the differentiation of lung epithelial cells and fibroblasts, and the pathogenesis of pulmonary fibrosis related to PQ. Inhibition of the Wnt/β-catenin signaling pathway may be investigated further as a potential fibrosis suppressor for pulmonary fibrosis therapy. [ABSTRACT FROM AUTHOR]

It is highly desirable to develop novel multifunctional wound dressing materials capable of delivering active molecules capable of resolving bacterial infections and replenishment of appropriate growth factors for bacteria-infected wound healing. Polysaccharides have numerous biomedical benefits and have been widely used to construct biomaterial scaffolds. Herein, multifunctional chitosan/alginate hydrogel decorated with β-cyclodextrin (β-CD) modified polydopamine (PDA)-bioactive glass (BG) nanoparticles (NPs) integrating photothermal performance and nitric-oxide release activities for the treatment of bacterially infected wounds is presented. As the NO precursor N , N ′-di-sec-butyl-N,N′-dinitroso-1,4-phenylenediamine (BNN6) encapsulated into the hydrophobic cavity of β-CD on the PDA-coated BG NPs, the resultant NO@CD-PDA/BG NPs, are imparted with the feature of NIR triggered NO release and desired PTT/NO synergetic antibacterial effects. Furthermore, the release of NO, Ca, and Si ions from the NO@CD-PDA/BG NPs, has the benefit of regulating inflammation, promoting fibroblast proliferation, and stimulating angiogenesis. Besides, the chitosan/alginate hydrogel scaffolds provided a suitable microenvironment to accelerate wound healing. By applying the multifunctional chitosan/alginate nanocomposite hydrogel to S. aureus -infected full-thickness skin defect mouse model, the authors demonstrated that chitosan/alginate nanocomposite hydrogel has multiple functions in preventing bacterial infections, accelerating angiogenesis and wound regeneration, indicating promising application in wound healing. [Display omitted] [ABSTRACT FROM AUTHOR]

High quality crystal AgGaGe 5 S 12 (AGGSe), a promising infrared (IR) nonlinear optical (NLO) material, was grown using seed aided Bridgman Stockbarger technique with dimension size 30 mm in diameter and 60 mm in length. The crystal was characterized with X-ray diffraction, rocking curve, transmission spectrum and laser induced damage threshold (LIDT). The FWHM of the (2 1 0) peak is about 0.06° and the IR transmission is about 61% in an 2 mm thick sample, mean absorption 0.04–0.08 cm −1 in the range 0.95–15 μm. The surface LIDT was measured to be 220 MW/cm 2 , about triple the value of high quality AgGaS 2 crystal with other experimental variable invariant. It may be good candidates for high-power NLO application. [ABSTRACT FROM AUTHOR]

BaGa 4 Se 7 is a new promising infrared nonlinear optical crystal. Recently, efforts are focused on the growth of high-quality single crystals. Single crystal with size of ϕ25 (diameter) × 35(length) mm3 was grown using vertical gradient freeze technique (VGF) for the first time. The yield of crack free crystals was greatly improved by selecting seed orientation for directional growth. Especially, the absorption coefficient of the BaGa 4 Se 7 crystal is as low as 0.02 cm−1 at 2.05 µm, which means that the as-grown crystal can be used to fabricate optical elements directly and does not need post-thermal annealing like other growth methods. The as-grown crystals were also characterized by X-ray diffraction (XRD), transmission spectra, and optical homogeneity etc. The BGSe-OPO elements were fabricated for infrared nonlinear optical experiments. [ABSTRACT FROM AUTHOR]

• Polycrystalline sample of BGSe was synthesized by high pressure method firstly. • High quality BGSe single crystal with dimensions of Φ40 mm × 180 mm was grown. • The absorption coefficient of a 2.5 mm thick device is 0.017 cm−1@4 μm. • The laser damage threshold was measured to be 7.075 J/cm2 using a 1.064 μm laser. BaGa 4 Se 7 (BGSe), as a promising new infrared nonlinear optical (IR NLO) crystal, has been widely studied in recent years due to its outstanding overall properties and IR laser output performance. In this paper, the synthesis method of polycrystalline sample and the temperature field used in crystal growth of BGSe were improved. More than 200 g BGSe polycrystalline sample can be synthesized by high pressure synthesis in just 2 days. The crystal growth temperature field can be designed with the use of COMSOL MultiphysicsTM simulation software, and the experimental results fit well with the simulation results. A high-quality crystal with dimensions up to Φ40 mm × 180 mm was grown successfully by the Bridgman-Stockbarger method. The surface laser damage threshold was measured to be 7.075 J/cm2 (peak on-axial fluence) using a 1.064 μm laser under conditions of 5 ns pulse width, 1 Hz frequency, and 0.12 mm spot size. The absorption coefficient was 0.017 cm−1@4 μm for an uncoated sample. [ABSTRACT FROM AUTHOR]

Abstract: ZnGeP2 crystal is one of the most promising materials for infrared nonlinear optical applications. However, the near-band-edge absorption of native defects degrades the performance of ZGP-OPO device. The single-zone-annealing furnaces were utilized to anneal ZGP samples. The optimal annealing temperature was 600°C and the optimal annealing atmosphere was ZGP powder vapor. For further annealing effects, the two-zone-annealing method was adopted to anneal ZGP crystals for the first time. The absorption coefficient can be reduced to 0.06cm−1 at 2μm and the resistivity can be increased from 5.8×107 Ωcm to 4.1×109 Ωcm. The results indicate that the annealed ZnGeP2 crystals could be used as OPO devices. The mechanism of the two-zone-annealing effects has been briefly discussed in this paper. [Copyright &y& Elsevier]