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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]

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]

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]

Paraquat (PQ), as a widely used herbicide, is highly toxic to human. PQ‐induced pulmonary fibrosis is the main reason for respiratory failure and death. In PQ‐poisoned mice, we find abundant senescent epithelial cells in the lung tissues, which can contribute to the activation of pulmonary fibroblasts. Ginsenoside Rg1 (Rg1), the main active component of ginseng, possess beneficial properties against aging. In our work, we aimed to investigate the potential protective effects of Rg1 on PQ‐induced pulmonary fibrosis and the underlying mechanism. In vivo, the treatment of Rg1 can attenuate PQ‐induced pulmonary fibrosis and decrease senescence and senescence associated secretory phenotype (SASP) expression. In vitro, Rg1 can effectively eliminate senescent cells via apoptosis, but not normal cells. In addition, we demonstrate that Rg1 can enhance autophagy activity via inducing the expression of ATG12. Inhibition of autophagy via 3‐MA or transfection of the siRNA targeting ATG12 can impair the antiaging effect of Rg1. Taken together, our data implicates that Rg1 can protect pulmonary epithelial cells from PQ‐induced cellular senescence in an ATG12 dependent manner, which may provide a preventive and therapeutic strategy for PQ poisoning‐induced pulmonary fibrosis. [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]

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]

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]

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]

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]

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]

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]

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]

Background: Sepsis-related acute respiratory distress syndrome (ARDS) is a fatal disease without effective therapy. Kaempferol is a flavonoid compound extracted from natural plant products; it exerts numerous pharmacological effects. Kaempferol attenuates sepsis-related ARDS; however, the underlying protective mechanism has not been elucidated completely., Objective: This study aimed to use network pharmacology and experimental verification to investigate the mechanisms by which kaempferol attenuates sepsis-related ARDS., Methods: We screened the targets of kaempferol by PharMapper, Swiss Target Prediction, and CTD database. We identified the targets of sepsis-related ARDS by GeneCards, DisGeNet, OMIM, and TTD. The Weishengxin platform was used to map the targets of both kaempferol and sepsis-related ARDS. We created a Venn diagram to identify the intersection targets. We constructed the "component-intersection targets-disease" network diagram using Cytoscape 3.9.1 software. The intersection targets were imported into the STRING database for developing the protein-protein interaction network. Metascape was used for the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. We selected the leading 20 KEGG pathways to establish the KEGG relationship network. Finally, we performed experimental verification to confirm our prediction results., Results: Through database screening, we obtained 502, 360, and 78 kaempferol targets, disease targets of sepsis-related ARDS, and intersection targets, respectively. The core targets consisted of tumor necrosis factor-alpha (TNF-α), interleukin (IL)-6, albumin (ALB), IL-1β, and AKT serine/ threonine kinase (AKT)1. GO enrichment analysis identified 426 items, which were principally involved in response to lipopolysaccharide, regulation of inflammatory response, inflammatory response, positive regulation of cell migration, positive regulation of cell adhesion, positive regulation of protein phosphorylation, response to hormone, regulation of reactive oxygen species (ROS) metabolic process, negative regulation of apoptotic signaling pathway, and response to decreased oxygen levels. KEGG enrichment analysis identified 151 pathways. After eliminating the disease and generalized pathways, we obtained the hypoxia-inducible factor 1 (HIF-1), nuclear factor κB (NF-κB), and phosphoinositide 3-kinase (PI3K)-Akt signaling pathways. Our experimental verification confirmed that kaempferol blocked the HIF-1, NF-κB, and PI3K-Akt signaling pathways, diminished TNF-α, IL-1β, and IL-6 expressions, suppressed ROS production, and inhibited apoptosis in lipopolysaccharide (LPS)-induced murine alveolar macrophage (MH-S) cells., Conclusion: Kaempferol can reduce inflammatory response, ROS production, and cell apoptosis by acting on the HIF-1, NF-κB, and PI3K-Akt signaling pathways, thereby alleviating sepsis- related ARDS., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Two-dimensional hexagonal boron phosphide presents great potential in applications of electronics and optoelectronics due to its high carrier mobility and moderate band gap. In this work, we investigate the effect of stress and electric field on the electronic properties of hexagonal boron phosphide layers based on first-principles calculations. We find that both the band gap and the carrier effective masses of hexagonal boron phosphide monolayer gradually increase with stress from compression to tension. As for hexagonal boron phosphide bilayer with two stacking orders (AB&#95;B-P and AB&#95;B-B) upon applied electric field, the band gap monotonously increases with the enhancement of electric field for AB&#95;B-P bilayer, while it undergoes a band gap closing and reopening process for AB&#95;B-B bilayer. We employ the tight-binding model to explain the mechanism of different band gap variations of two stacking orders with electric field. Moreover, we discuss the band gap variation of hexagonal boron phosphide bilayer with combined effect of stress and electric field. The investigation here presents an insight into the effective manipulation towards the electronic properties of hexagonal boron phosphide, which will further enable the broader applications of the hexagonal boron phosphide in modern electronic and optoelectronic fields.

Graphene-like hexagonal boron phosphide with its moderate band gap and high carrier mobility is considered to be a high potential material for electronics and optoelectronics. In this work, the tight-binding Hamiltonian of hexagonal boron phosphide monolayer and bilayer with two stacking orders are derived in detail. Including up to fifth-nearest-neighbor in plane and next-nearest-neighbor interlayer hoppings, the tight-binding approximated band structure can well reproduce the first-principle calculations based on the screened Heyd-Scuseria-Ernzerhof hybrid functional level over the entire Brillouin zone. The band gap deviations for monolayer and bilayer between our tight-binding and first-principle results are only 2 meV. The low-energy effective Hamiltonian matrix and band structure are obtained by expanding the full band structure close to the K point. The results show that the iso-energetic lines of maximum valence band in the vicinity of K point undergo a pseudo-Lifshitz transition from h-BP monolayer to AB&#95;B-P or AB&#95;B-B bilayer. The mechanism of pseudo-Lifshitz transition can be attributed to two interlayer hoppings rather than one.

Recently developed chalcogenides nonlinear optical crystals have potential application in mid- to far-infrared laser fields. However, high-quality single crystals are hard to be prepared because of high vapor pressure of sulfur component and decomposition of chalcogenides during the polycrystalline synthesis and single-crystal growth. A pressure-assisted technique was performed to prepare stoichiometric AgGaS 2 and AgGaGeS 4 polycrystalline materials. On the basis of the synthesized polycrystalline materials, high-quality AgGaS 2 and AgGaGeS 4 single crystals were successfully obtained using the seed directional Bridgman method with a well-designed crucible-capsule technique. These single crystals possess high homogeneity and low absorption coefficient, making it can be applied in nonlinear optical experiments. The pressure-assisted method can also be suitable to prepare other chalcogenide and phosphide compounds. The method of polycrystalline synthesis and single crystals growth described in this work will be helpful for preparing other chalcogenides nonlinear optical crystals.