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After being banned from using many important foreign industrial software, China promotes the development of domestic industrial software as a national strategic goal. There are many literatures analyzing the promotion effect of policy on technological innovation of China’s industrial software, but there is still a gap in the research on the effect of financial structure. Taking Empyrean Technology Company as an example, this paper analyzes the effect of financing structure on technological innovation in company’s different development periods. In entrepreneurship stage, the company’s technological innovation is mainly driven by internal financing and government subsidy. In growth stage, equity financing plays a greater role in promoting technological innovation than debt financing. Therefore, the study suggests China’s industrial software enterprises to actively apply for government subsidies in entrepreneurship stage and to explore equity financing channels in growth stage. Chinese central government can encourage more venture capital to be invested in industrial software industry by improving equity exit mechanism.

CeSb2 is a homologue of rare-earth diantimonides. This work reports a systematic study of a series of high-quality single crystals of CeSb2 grown by a self-flux method, which is a heavy fermion Kondo metal with intricate magnetic transitions. We have grown four types of crystals with different initial material ratios in order to investigate the effect of growth conditions on the quality of the as-grown crystals. The phase purity, morphology and composition of the synthesized samples were studied with X-ray diffraction, scanning electron microscopy, electron-probe microanalysis, and Raman-scattering spectroscopy to evaluate their quality. It is found that an inappropriate raw material ratio will lead to the inhomogeneity and poor crystallinity of the as-grown crystal. In addition, the electrical transport properties of the as-grown crystals were measured, from which the residual resistivity ratios were extracted to further examine the homogeneity and crystalline quality. Furthermore, the magnetoresistance properties of CeSb2 were observed. Through a systematic study on CeSb2, the most suitable starting ratio for the growth of CeSb2 was obtained, which might serve as a guide for the growth of other light rare-earth diantimonides.

We investigate quantum inspired algorithms to compute physical observables of quantum many-body systems at finite energies. They are based on the quantum algorithms proposed in [Lu et al. PRX Quantum 2, 020321 (2021)], which use the quantum simulation of the dynamics of such systems, as well as classical filtering and sampling techniques. Here, we replace the quantum simulation by standard classical methods based on matrix product states and operators. As a result, we can address significantly larger systems than those reachable by exact diagonalization or by other algorithms. We demonstrate the performance with spin chains up to 80 sites.

Background The Goto-Kakizaki (GK) rat, developed from repeated inbreeding of glucose-intolerant Wistar rats, has been widely used to explore the development of spontaneous type-2 diabetes mellitus (T2DM). However, the gastric microbiota of GK and Wistar rats are still unclear. This study aimed to understand the gastric microbiota characteristics of GK rats by comparing it with non-diabetic Wistar rats. Materials and Methods Male Wistar rats and GK rats were housed in specific pathogen-free (SPF) environment for 12 weeks with free access to sterilized food and water. Body weight and random blood glucose (BG) levels were determined. At the end of the experiment, the gastric contents of the rats were collected for the identification of gastric microbiota using 16S rRNA gene sequencing. Results The richness of gastric microbiota in GK rats was similar to that of Wistar rats (P > 0.05). The results of Shannon, Simpson, beta diversity indices, and ANOSIM analysis showed that alpha and beta diversity of gastric microbiota in GK rats were significantly lower than that of Wistar rats (P < 0.01). Firmicutes (96.0%), Proteobacteria (1.9%) and Cyanobacteria (0.8%) were the dominant gastric microbiota in GK rats accounting for 72.9%, 14.7% and 10.9%, respectively. Linear discriminant analysis effect size (LEfSe) revealed that phylum Firmicutes and four genera (Anaerovibrio, Collinsella, Prevotellaceae_UCG_001, and Lactobacillus) were significantly abundant in the stomachs of GK rats. In contrast, seven genera (unidentified_Chloroplast, Porphyromonas, Neisseria, Rubrobacter, Veillonella, Lachnospiraceae_UCG_005, and unidentified_Erysipelotrichaceae) were significantly abundant in the stomachs of Wistar rats. Blood glucose was positively correlated with Anaerobibrio and Lactobacillus, and negatively correlated with four genera (Porphyromonas, Rubrobacter, Lachnospiraceae_UCG_005, and unidentified_Erysipelotrichaceae). In addition, chemoheterotrophy and fermentation were the most important functions of gastric microbiota. Conclusion The gastric microbiota of GK rats with spontaneous T2DM showed the typical characteristics of low diversity and significant enrichment of Firmicutes phylum and four genera (Anaerovibrio, Collinsella, Prevotellaceae_UCG_001, and Lactobacillus) compared with gastric microbiota of Wistar rats.

Background The mechanism of early enteral nutrition on intestinal mucosal barrier is still not fully understood and the direct evidence to demonstrate the protective effects of early enteral nutrition against remote organs injury induced by severe acute pancreatitis is lacking. Methods Rats were randomly divided into three groups: 1) only flip pancreas and free diet (n = 8); 2) severe acute pancreatitis and total parenteral nutrition (n = 15); 3) severe acute pancreatitis and early enteral nutrition (n = 15). Severe acute pancreatitis was induced by the retrograde injection of pancreaticobiliary duct with sodium taurocholate. Nutritional supplementation was administered starting 12 hours after induction of pancreatitis. The samples were obtained after the treatment of nutrition 72 hours. Results The mortality was not significant difference between the experimental groups. The pathology of ileum and the content of serum diamine oxidase were significantly lower in early enteral nutrition group than total parenteral nutrition group. The expression of tight junction ZO-1, Occludin and Claudin-1 proteins and the intraepithelial CD8+ and TCRγδ+ lymphocytes were significantly higher in early enteral nutrition group than total parenteral nutrition group. The content of the serum amylase and endotoxin were significantly lower in early enteral nutrition group than total parenteral nutrition group. There was a tendency of decreased pancreas and lung pathology scores in early enteral nutrition group, but the difference between total parenteral nutrition and early enteral nutrition groups was not significant. Conclusion The early enteral nutrition could significantly improve the expression of the tight junctions and intraepithelial lymphocytes, accompanied by improved intestinal mucosal barrier and endotoxin, but failed to the pancreas and lung injury compared to total parenteral nutrition in the rat model of severe acute pancreatitis.

The Tm3+ and Ho3+ ions co-doped LaF3 crystal was grown successfully by the Bridgman method for the first time. X-ray diffraction, thermal conductivity, absorption, and fluorescence properties were investigated systematically. The thermal conductivity is 1.99 W/(mK) at room temperature. The absorption cross-section at 792 nm and emission cross-section at 1987 nm are 0.18 × 10 − 20 cm2 and 0.32 × 10 − 20 cm 2 , respectively. The Tm,Ho:LaF3 crystal exhibits wide absorption band (38 nm) and emission band (140 nm), as well as long fluorescence lifetime (17.56 ms). With a 10-mm-long sample, the output power of 574 mW at 2047 nm was obtained for the incident power of 3.53 W with a slope efficiency of 18.5%. It can be proposed that Tm,Ho:LaF3 crystal can be a potential material for LD-pumped tunable and ultra-short pulse laser applications operating at around 2 μ m .

The efficient 2.87 μ m emission of Ho3+: 5I6 → 5I7 transition via Nd3+ sensitization in Nd,Ho:LaF3 crystal was obtained under 808 nm LD excitation for the first time. The lifetime of Ho3+:5I7 decreases dramatically from 26.28 ms to 6.41 ms via Nd3+ co-doping. The mechanism of sensitization and deactivation by Nd3+ was investigated compared with the Ho:LaF3 crystal. The absorption cross-section, emission cross-section, and fluorescence quantum efficiency were estimated and discussed. All the results indicate Nd,Ho:LaF3 crystal an attractive gain medium for solid-state lasers around 2.87 µm under an 808 nm LD pump.

It is a challenging task to handle the vector field visualization at local critical points. Generally, topological based methods firstly divide critical regions into different categories, and then process the different types of critical regions to improve the effect, which pipeline is complex. In the paper, a learning based multi-task super resolution (SR) method is proposed to improve the refinement of vector field, and enhance the visualization effect, especially at the critical region. In detail, the multi-task model consists of two important designs on task branches: one task is to simulate the interpolation of discrete vector fields based on an improved super-resolution network; and the other is a classification task to identify the types of critical vector fields. It is an efficient end-to-end architecture for both training and inferencing stages, which simplifies the pipeline of critical vector field visualization and improves the visualization effect. In experiment, we compare our method with both traditional interpolation and pure SR network on both simulation data and real data, and the reported results indicate our method lower the error and improve PSNR significantly.

A novel Yb3+, Ho3+:LaF3 crystal was successfully grown and analyzed. Intense emission at 2.87 µm was observed in Yb3+, Ho3+:LaF3 crystal for the first time. Yb3+ ions not only provide sensitization mechanism for conventional LD pump, but also reduce self-termination by comparing with Ho3+:LaF3 crystal. The emission cross-section, quantum efficiency and fluorescence branching ratio at 2.87 µm are calculated to be 1.21 × 10–20 cm2, 82.5%, and 27.1%, respectively. The results indicate Yb3+, Ho3+:LaF3 crystal an attractive host for solid-state lasers around 2.87 µm under a 974 nm LD pump.

NdB6 can effectively react with the surface titanium oxide films to form an initial NdBO3 layer at about 670 °C, just prior to their dissolution. Two thirds of all the oxygen scavenged during sintering occurred in the α-Ti phase region through this reaction. NdBO3 layer continues to grow by diffusion of oxygen until 1130 °C, beyond which NdBO3 decomposes into Nd2O3 dispersoids and Nd2O3 further reacts with chlorine to form NdClxOy. The unique oxygen-scavenging process prior to the active dissolution of oxide film makes NdB6 more effective in scavenging oxygen than other rare earth hydrides, resulting in better tensile elongation. The addition of NdB6 also leads to the improved sintered density, substantial microstructural refinement and dispersion strengthening by Nd-containing compounds and TiB. The optimal addition level of NdB6 is 0.3 wt.%, beyond which large Nd2O3 aggregates and an increased number of TiB whiskers were formed. This is detrimental to the ductility.

In this study, a 2 at.% erbium doped cerium trifluoride (Er:CeF3) single crystal was grown using the Bridgman method. The consequent absorption, infrared transmittance, and fluorescence spectra were recorded. The spectroscopic properties of Er:CeF3 crystals were intensively studied based on the Judd–Ofelt (J–O) theory. The Ω2, Ω4, and Ω6 parameters were fitted to be 5.206×10−20, 1.805×10−20, and 3.06×10−20 cm2, respectively. The emission cross-section centered at 1564.6 nm was calculated to be 1.053×10−20 cm2, and the corresponding fluorescence lifetime was measured to be 1.675 ms. Additionally, the magneto-optical (MO) performance of the Er:CeF3 crystal was investigated for the first time. The Verdet constants of Er:CeF3 at 532, 632.8, 1064, and 1310 nm are 231.0, 165.4, 43.4, and 24.4 rad·T−1·m−1, respectively, which are significantly higher than those of pure CeF3 and traditional Tb3Ga5O12. The results show that the Er:CeF3 crystal can be applied both to solid-state lasers and Faraday devices.

Background The Goto-Kakizaki (GK) rat, developed from repeated inbreeding of glucose-intolerant Wistar rats, has been widely used to explore the development of spontaneous type-2 diabetes mellitus (T2DM). However, the gastric microbiota of GK and Wistar rats are still unclear. This study aimed to understand the gastric microbiota characteristics of GK rats by comparing it with non-diabetic Wistar rats. Materials and Methods Male Wistar rats and GK rats were housed in specific pathogen-free (SPF) environment for 12 weeks with free access to sterilized food and water. Body weight and random blood glucose (BG) levels were determined. At the end of the experiment, the gastric contents of the rats were collected for the identification of gastric microbiota using 16S rRNA gene sequencing. Results The richness of gastric microbiota in GK rats was similar to that of Wistar rats (P > 0.05). The results of Shannon, Simpson, beta diversity indices, and ANOSIM analysis showed that alpha and beta diversity of gastric microbiota in GK rats were significantly lower than that of Wistar rats (P < 0.01). Firmicutes (96.0%), Proteobacteria (1.9%) and Cyanobacteria (0.8%) were the dominant gastric microbiota in GK rats accounting for 72.9%, 14.7% and 10.9%, respectively. Linear discriminant analysis effect size (LEfSe) revealed that phylum Firmicutes and four genera (Anaerovibrio, Collinsella, Prevotellaceae_UCG_001, and Lactobacillus) were significantly abundant in the stomachs of GK rats. In contrast, seven genera (unidentified_Chloroplast, Porphyromonas, Neisseria, Rubrobacter, Veillonella, Lachnospiraceae_UCG_005, and unidentified_Erysipelotrichaceae) were significantly abundant in the stomachs of Wistar rats. Blood glucose was positively correlated with Anaerobibrio and Lactobacillus, and negatively correlated with four genera (Porphyromonas, Rubrobacter, Lachnospiraceae_UCG_005, and unidentified_Erysipelotrichaceae). In addition, chemoheterotrophy and fermentation were the most important functions of gastric microbiota. Conclusion The gastric microbiota of GK rats with spontaneous T2DM showed the typical characteristics of low diversity and significant enrichment of Firmicutes phylum and four genera (Anaerovibrio, Collinsella, Prevotellaceae_UCG_001, and Lactobacillus) compared with gastric microbiota of Wistar rats.

High quality Yb and Ho co-doped Y3Al5O12 single crystal fibers have been successfully grown by the laser heated pedestal growth method of up to 124 mm in length and 450 μm in diameter for the first time. The results of inductively coupled plasma-atomic emission spectrometry analysis, X-ray diffraction and Raman spectroscopy reveal that the lattice structure and doping concentrations of the SCF are the same as that of the bulk. Scanning electron microscopy microphotographs shows that the fibers only have minor diameter fluctuations within 0.5%.

The highly transparent neodymium-doped CeF3 (Nd:CeF3) single crystal with diameter of 20 mm × 35 mm was grown by the Bridgman Stockbarger (BS) method. The optical and magneto-optical (MO) performances of Nd:CeF3 were experimentally investigated in UV–Vis and near-IR spectral range. Notably, Nd:CeF3 exhibits high transparency and significantly enhanced Faraday rotation. Compared with commercial terbium gallium garnet (TGG), Nd:CeF3 has higher Verdet constants at different measured wavelengths. The bulk laser-induced damage of c-cut Nd:CeF3 crystal was also determined by R-on-1 method. All the results demonstrate that the properties of Nd:CeF3 are superior to those of CeF3 and TGG. The excellent MO properties of Nd:CeF3 with a used wavelength of 0.3–2.2 µm are especially important for high power isolators in order to cover UV–Vis and the entire near-IR range.

Residual infrared absorption is a key problem affecting the laser emission efficiency of Ti:sapphire crystal. In this paper, the origin of residual infrared absorption of Ti:sapphire crystal is systematically studied by using the first principles method. According to the contact conditions of O octahedron in the crystal structure of Al 2 O 3 , four Ti 3 + − Ti 3 + ion pair models and three Ti 4 + − Ti 3 + ion pair models were defined and constructed. For what we believe is the first time, the near-infrared absorption spectra consistent with the experimental results were obtained in specific theoretical models. The electronic structures, absorption spectra, and charge distributions calculated show that the line-contact Ti 3 + − Ti 3 + ion pair with antiferromagnetic coupling and the face-contact Ti 4 + − Ti 3 + ion pair are two main contributors to the residual infrared absorption of Ti:sapphire, while some other ion pair models provide a basis to explain more complex residual infrared absorption.

Purpose There is a resurgence in the adaptive reuse of buildings. However, there is a lack of literature that pulls all the strands of adaptive reuse together. Furthermore, despite claims that it is motivated by the 3 Es of the sustainability triangle, the authors could find no research that critiques adaptive reuse from this perspective. The purpose of this study is to review the literature to collect pertinent information in a single place and to critically examine whether adaptive reuse incorporates the 3 Es of sustainability. Design/methodology/approach The methodological approach of this study is a literature review and a critical analysis of the practice of adaptive review. Findings Adaptive reuse is concentrated at the environment and economic development corners of the sustainability triangle. There are positive interactions along this edge. The authors attribute this to the fact that the same actors – the private and public sectors – are located at both corners of the triangle, and they have shared interests. This is different from the wider sustainability literature, where major actors at each corner are different and tensions along each edge are resolved through mediation. In adaptive reuse, there are no actors at the equity corner of the triangle, and there are minimal attempts to address concerns along the equity–environment and equity–economic development edges of the triangle. Research limitations/implications This study focuses on the USA. Practical implications This study suggests policy interventions that address the equity issue in adaptive reuse. Originality/value This is the first study to provide a succinct review of contemporary adaptive reuse and that places the practice within the framework of the 3 Es of sustainability.

Insects and hummingbirds exhibit extraordinary flight capabilities and can simultaneously master seemingly conflicting goals: stable hovering and aggressive maneuvering, unmatched by small scale man-made vehicles. Flapping Wing Micro Air Vehicles (FWMAVs) hold great promise for closing this performance gap. However, design and control of such systems remain challenging due to various constraints. Here, we present an open source high fidelity dynamic simulation for FWMAVs to serve as a testbed for the design, optimization and flight control of FWMAVs. For simulation validation, we recreated the hummingbird-scale robot developed in our lab in the simulation. System identification was performed to obtain the model parameters. The force generation, open-loop and closed-loop dynamic response between simulated and experimental flights were compared and validated. The unsteady aerodynamics and the highly nonlinear flight dynamics present challenging control problems for conventional and learning control algorithms such as Reinforcement Learning. The interface of the simulation is fully compatible with OpenAI Gym environment. As a benchmark study, we present a linear controller for hovering stabilization and a Deep Reinforcement Learning control policy for goal-directed maneuvering. Finally, we demonstrate direct simulation-to-real transfer of both control policies onto the physical robot, further demonstrating the fidelity of the simulation., The code is available at (https://github.com/purdue-biorobotics/flappy). 6 pages, 10 figure, accepted at ICRA 2019

The novel Ho,Pr:CaGdAlO4 crystal was grown successfully by the Czochralski method. The crystal structure, segregation, absorption and luminescence properties were investigated in detail. The concentration of Pr3+ and Ho3+ ions are 0.76 × 1020 cm−3 and 3.49 × 1020 cm−3, respectively. The effect of Pr3+ co-doping on the ~2.86 μm emission of Ho3+ was analyzed. The fluorescence intensity of Ho,Pr:CaGdAlO4 is three times higher than that of Ho:CaGdAlO4. The efficiency of energy transfer from Ho3+: 5I7 to Pr3+: 3F2 energy level was calculated to be 96.2%, which restrains the self-termination effect to a large extent in Ho,Pr:CaGdAlO4 crystal. The absorption cross-section at 1146 nm is 0.83 × 10−20 cm2 with the FWHM of 19 nm. The fluorescence branching ratio, emission cross-section and measured fluorescence lifetime at 2.86 μm are 12.7%, 2.38 × 10−20 cm2 and 0.194 ms, respectively. All these results suggest that Ho,Pr:CaGdAlO4 crystal is promising candidate for the 2.86 μm laser application pumped by the 1150 nm Raman fiber laser.

A Nd:CeF3 crystal was grown successfully by the vertical Bridgman method. The polarized optical properties were investigated for the first time. Based on the Judd–Ofelt theory, the spectral parameters of Nd3+ were studied in detail by using the spectrum of the as-grown crystal. The peak absorption cross-section of σ-polarization at 791 nm is 1.59 × 10−20 cm2, the full width at half maximum (FWHM) is 10 nm. The peak emission cross-section of σ-polarization at 1070 nm is approximately 2.53 × 10−20 cm2, and the three peaks that make up the broadband peak have comparable value. The measured 4F3/2 level fluorescence lifetime is 0.406 ms. Moreover, segregation coefficient of Nd3+, thermal diffusivity coefficient, and thermal conductivity were also measured. We propose that the Nd:CeF3 crystal may be a promising material for 1 μm dual-wavelength laser applications.

is responsible for introducing research, attracting readers and other multiple functions, and has its own unique characteristics of discourse construction. Through objective analysis of the characteristics of discourse construction in abstracts published by Chinese and foreign scholars in international English journals, the accuracy of the expression of the articles can be increased. The author builds his own corpus and makes a contrastive analysis of the frequency, types and distribution of fuzzy restrictive language in each step of English abstracts in Chinese and foreign journals, and summarizes the unique short language types and textual functions of each step. The results show that the distribution trend of hedges in the fourth step of English abstracts in Chinese and foreign journals is generally the same, but there are significant differences in the types of use and the frequency of occurrence. Therefore, in English abstract writing, Chinese authors should properly use various types of rhetorical devices to enhance the diversity of language expression, so as to better obtain the recognition of readers.

A Tm:LuYO3 crystal was grown by the optical floating zone method for the first time. The XRD pattern shows that it belongs to the cubic crystal system (Ia‾3 space group). The absorption spectrum was used to investigate the emission properties with the help of the Judd-Ofelt theory. The emission cross-section at 2056 nm is 1.95 × 10 - 20 c m 2 . The Tm:LuYO3 crystal exhibits broad absorption band at around 800 nm with the FWHM of 48 nm and wide emission band at around 2 μ m with the FWHM of more than 200 nm. The potential utility of the Tm:LuYO3 crystal as tunable laser medium at ~2 μm can be expected.

A Ho3+-doped CeF3 crystal was successfully grown for the first time using the Bridgman method, and its spectral properties were studied. By analyzing the absorption and emission measurements of the Ho:CeF3 crystal with the Judd–Ofelt theory, the intensity parameters Ω2,4,6, emission cross-sections, gain cross-sections, and excited state lifetimes were calculated. It was found that the peak absorption cross-section around 447 nm is 0.4339 × 10−20 cm2, which matched to the commercially available blue laser diode lasers. The 2.0 μm excitation emission of the Ho:CeF3 crystal corresponding to the stimulated emission Ho3+:5I7→5I8 transition has an emission cross section of 0.24 × 10−20 cm2 with FWHM of 146 nm.

We report on wavelength extension of diode-pumped Tm:YLF crystal lasers. Using specifically coated end-face mirrors, we have achieved a simulataneous dual-wavelength laser at 2.05 and 2.3 μm with a maximum output power up to 1.33 W and slope efficiency of about 9.7% in continuous-wave regime, for the first time to the best of our knowledge. Moreover, using an un-doped YAG etalon for wavelength tuning, the 2.05 μm lasing wavelength can be shifted to as far as 2.1 μm. We believe that it is the first time that a Tm:YLF laser has been wavelength extended to that far. Using a Cr:ZnSe saturable absorber, a passively Q-switched Tm:YLF laser at 2.05 μm has also attained with a maximum average output power of 0.66 W. The shortest pulse width is 91.7 ns at pulse repetition rate of 8.47 kHz. This work has extended the operating wavelengths of Tm3+ lasers to that in general for Ho3+ lasers, which could be practically meaningful for various applications.

Supplemental Digital Content is available in the text, Background: Whether to conduct enteral nutrition in patients with severe acute pancreatitis (SAP) during the active phase of intestinal stress or to feed during remission remains controversial. This study was aimed to evaluate the efficacy and safety of enteral nutrition within 48 hours after admission in the patients with SAP or predicted severe acute pancreatitis (pSAP). Methods: We searched PubMed, EMBASE, Web of Science, and the Cochrane Library before December 2017. Randomized controlled trials of early enteral nutrition (starting within 48 hours after admission) versus late enteral nutrition or total parental nutrition in severe acute pancreatitis or predicted severe acute pancreatitis were selected. Results: Ten randomized controlled trials containing 1051 patients were included. Comparing early enteral nutrition to late enteral nutrition or total parental nutrition in SAP or pSAP, the pooled risk ratios were 0.53 (95% confidence interval [CI] 0.35–0.81, P = .003) for mortality, 0.58 (95% CI 0.43–0.77, P = .0002) for multiple organ failure (MOF), 0.50 (95% CI 0.33–0.75, P = .0008) for operative intervention, 0.75 (95% CI 0.61–0.93, P = .009) for systemic infection, 0.42 (95% CI 0.26–0.69, P = .0005) for local septic complications, 0.84 (95% CI 0.74–0.96, P = .01) for gastrointestinal symptoms. 0.87 (95% CI 0.74–1.02, P = .08) for systemic inflammatory response syndrome (SIRS), and 1.24 (95% CI 0.66–2.31, P = .50) for other local complications. Conclusions: Enteral nutrition within 48 hours after admission is efficient and safe for the patients with SAP or pSAP.

A Dy3+-doped CeF3 yellow region laser crystal was successfully grown using the Bridgman method. A 570 nm emission in Dy:CeF3 crystal was observed for the first time. By analyzing the absorption and emission measurements of the Dy:CeF3 crystal with the Judd–Ofelt theory, the intensity parameters Ω2,4,6, exited state lifetimes, branching ratios, and emission cross-sections were calculated. It is found that the Dy:CeF3 crystal has high emission cross section (0.9259 × 10−20 cm2) and long fluorescence lifetime (1.53 ms) corresponding to the stimulated emission of Dy3+:4F9/2 → 6H13/2 transition. We propose that the Dy:CeF3 crystal may be a promising material for 570 nm laser applications.

The Tm,Ho:Lu2O3 crystal was grown by the optical floating zone method for the first time. The XRD pattern shows that it belongs to the cubic crystal system (Ia‾3 space group). The absorption cross-section at 796 nm is 4.21 × 10 − 21 cm2, the full width at half maximum (FWHM) is 54 nm. The emission cross-section at 2092 nm is approximately 0.20 × 10 − 20 cm 2 . The broad fluorescence band extends to 2200 nm where almost no absorption was found. The fluoresce lifetime at 2092 nm is 3.73 ms. With the help of up-conversion spectra, the energy transfer mechanism between Tm3+ and Ho3+ ions was investigated systematically. The potential utility of the Tm,Ho:Lu2O3 crystal as tunable and ultra-short laser media at ~2.1 μm can be expected.

Some recent researches showed that retro reflector array (RRA) has installation superiorities that single retro reflector (RR) does not possess in the far-infrared (FIR) polarimeter/interferometer (PI) system for Tokamak. As a key precondition for replacing RR with RRA, the reflected light from RRA must change to Gaussian profile to guarantee the detectors get stronger signals and the threshold distance to Gaussian profile should be less than the optical path between the first wall and detectors. In this paper, the propagation properties of the reflected beams from RR and RRAs of different combinations have been measured by a beam profiler. The experimental results show that the reflected beam profiles from RRA of two retro reflectors (RRs) evolve into Gaussian distributions beyond a certain reflected optical distance and the reflected beam profiles from RRA of three RRs have a similar tendency to be Gaussian distributions with increasing reflected optical distance. The theory predictions, deriving from the integral theorem of Helmholtz and Kirchhoff, provide the same evolutions with experiments, but the threshold distances to Gaussian profile existing distinctions. These results suggest that RRA could be applied in the FIR PI system for the future ITER.

Objective. The aim of the present study was to examine whether Dai-Huang-Fu-Zi-Tang (DHFZT) could regulate mitochondrial permeability transition pore (MPTP) of intestinal mucosa epithelial cells for alleviating intestinal injury associated with severe acute pancreatitis (SAP).Methods. A total of 72 Sprague-Dawley rats were randomly divided into 3 groups (sham group, SAP group, and DHFZT group,n=24per group). The rats in each group were divided into 4 subgroups (n=6per subgroup) accordingly at 1, 3, 6, and 12 h after the operation. The contents of serum amylase, D-lactic acid, diamine oxidase activity, and degree of MPTP were measured by dry chemical method and enzyme-linked immunosorbent assay. The change of mitochondria of intestinal epithelial cells was observed by transmission electron microscopy.Results. The present study showed that DHFZT inhibited the openness of MPTP at 3, 6, and 12 h after the operation. Meanwhile, it reduced the contents of serum D-lactic acid and activity of diamine oxidase activity and also drastically relieved histopathological manifestations and epithelial cells injury of intestine.Conclusion. DHFZT alleviates intestinal injury associated SAP via reducing the openness of MPTP. In addition, DHFZT could also decrease the content of serum diamine oxidase activity and D-lactic acid after SAP.

Praseodymium-ion-doped gain materials have the superiority of lasing at various visible wavelengths directly. Simple and compact visible lasers are booming with the development of blue laser diodes in recent years. In this Letter, we demonstrate the watt-level red laser with a single blue laser diode and Pr:YLiF4 crystal. On this basis, the passively Q-switched pulse lasers are obtained with monolayer graphene and Co:ZnO thin film as the Q-switchers in the visible range.

There are many factors influencing second language acquisition, such as learner external factors including social factors, the input of second language acquisition and the relationship between acquisition; internal factors including the transfer of language, cognition of second language and language universals, etc, which influence the psychological factors of learner's second language; individual differences include some factors in physiological emotion, cognition, and learning strategies. This article is to explore the role of learners in second language acquisition from the perspective of individual differences (age, aptitude, learning motivation).

It is clear that euphemism is a form of language intentionally created in different language communities and diverse social levels. Speakers can remove direct speech to weaken the negative association and uncomfortable feelings provoked by the euphemized object. However, in linguistic communication, euphemism is opposite to the cooperation principle, though it is closely relevant to politeness.