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A new steganographic method by pixel-value differencing (PVD) using general quantization ranges of pixel pairs' difference values is proposed. The objective of this method is to provide a data embedding technique with a range table with range widths not limited to powers of 2, extending PVD-based methods to enhance their flexibility and data-embedding rates without changing their capabilities to resist security attacks. Specifically, the conventional PVD technique partitions a grayscale image into 1 × 2 non-overlapping blocks. The entire range [0, 255] of all possible absolute values of the pixel pairs' grayscale differences in the blocks is divided into multiple quantization ranges. The width of each quantization range is a power of two to facilitate the direct embedding of the bit information with high embedding rates. Without using power-of-two range widths, the embedding rates can drop using conventional embedding techniques. In contrast, the proposed method uses general quantization range widths, and a multiple-based number conversion mechanism is employed skillfully to implement the use of non-power-of-two range widths, with each pixel pair being employed to embed a digit in the multiple-based number. All the message bits are converted into a big multiple-based number whose digits can be embedded into the pixel pairs with a higher embedding rate. Good experimental results showed the feasibility of the proposed method and its resistance to security attacks. In addition, implementation examples are provided, where the proposed method adopts non-power-of-two range widths and employs multiple-based number conversion to expand the data-hiding and steganalysis-resisting capabilities of other PVD methods. [ABSTRACT FROM AUTHOR]

The growing preference for incorporating microbial aspartic proteases in industries is due to their high catalytic function and high degree of substrate selectivity. These properties, however, are attributable to molecular alterations in their structure and a variety of other characteristics. Molecular tools, functional genomics, and genome editing technologies coupled with other biotechnological approaches have aided in improving the potential of industrially important microbial proteases by addressing some of their major limitations, such as: low catalytic efficiency, low conversion rates, low thermostability, and less enzyme yield. However, the native folding within their full domain is dependent on a surrounding structure which challenges their functionality in substrate conversion, mainly due to their mutual interactions in the context of complex systems. Hence, manipulating their structure and controlling their expression systems could potentially produce enzymes with high selectivity and catalytic functions. The proteins produced by microbial aspartic proteases are industrially capable and far-reaching in regulating certain harmful distinctive industrial processes and the benefits of being eco-friendly. This review provides: an update on current trends and gaps in microbial protease biotechnology, exploring the relevant recombinant strategies and molecular technologies widely used in expression platforms for engineering microbial aspartic proteases, as well as their potential industrial and biotechnological applications. [ABSTRACT FROM AUTHOR]

Dihydroquinazolinone (DHQZ) has recently been harnessed as a ketone‐derived pro‐aromatic reagent extensively employed in (metalla)photoredox reactions as versatile group transfer agents. In this work, we outline a column chromatography‐free protocol for the multigram‐scale synthesis of pro‐aromatic DHQZs as well as its use in a gram‐scale nickel/photoredox dual‐catalyzed cross‐coupling in single‐batch, photoflow, and simultaneous multiple smaller batches. While the single‐batch approach leveraged moderate yields, a simple plug‐flow photoreactor also exhibited amenable productivity (up to 45 % yield) despite the use of a heterogeneous base. Meanwhile, performing the metallaphotoredox‐catalyzed reaction in multiple smaller batches in an improvised photoreactor facilitated high yields of up to 59 % and good reproducibility, implying a convenient alternative in the absence of photoflow setups. [ABSTRACT FROM AUTHOR]

Temperature dependent thermal and spectroscopic properties of Yb:LuAG crystal were presented in detail at temperature ranging from 298 to 77 K. We measured the thermal expansion coefficient, thermal conductivity and specific heat as functions of temperatures. Then, the thermal shock resistance parameters were evaluated, which were significantly increased from 0.75×106 to 10.19×106 W/m as temperature varies from 298 to 77 K. Moreover, the spectroscopic parameters, such as absorption and emission cross-sections and fluorescence lifetime were also determined. In order to evaluate Yb:LuAG's potential to generate high power laser output, a numerical model was employed by finite element method and ray tracing method. We simulated the temperature distribution in Yb:LuAG crystal slab when temperature reduces from 298 to 77 K. The maximum principal stress in slab decreases from 74.8 to 29.4 MPa and the maximum principal strain decreases from 23.76×10-5 to 7.63×10-5 for a given heat power of 1500 W with the temperature dropping from 298 to 77 K. The simulated near-field and far-field profiles of probe beam demonstrated a better beam quality at low temperature. These results indicate that cryogenically cooled Yb:LuAG is a promising laser medium for high power output while maintaining good beam quality [ABSTRACT FROM AUTHOR]

Temperature-dependent thermal and spectroscopic properties of Nd:YVO4 crystal at temperatures ranging from 77 to 300 K are presented. Thermal properties including specific heat, thermal expansion coefficient, and thermal conductivity are investigated. The spectroscopic parameters, such as absorption, fluorescence, lifetime are also studied. The calculated absorption and emission cross-sections together with relevant thermal properties provide important information for designing cryogenically cooled near infrared laser. Furthermore, we experimentally explore continuous wave (CW) laser performances under various cryogenic temperatures. A maximum output power of 2.13 W is obtained at an incident pump power of 3.7 W at 150 K, corresponding to an optical-to-optical conversion efficiency of 57.6%. [ABSTRACT FROM AUTHOR]

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By fusing energy-transfer visible-light photocatalysis and heterogeneous Brønsted acid catalysis, an operationally straightforward synthesis of oxaspirolactones, natural scaffolds present in many molecules with therapeutic properties, is described. Sequential photooxygenation with singlet oxygen (1O2) and acid-facilitated ketalization of silylated hydroxyalkyl furans affords the target compounds in quantitative yields and broad scope while only using green solvents and an energy-saving light source. In addition, translation of the developed method into photoflow and chromatography-grade silica gel-supported solvent-free conditions demonstrates good scalability and simplification of the reaction process. The latter procedure was further shown to be amenable to sunlight and air as natural sources of light and molecular oxygen, which are necessary for the reaction. Preliminary control studies are also presented to further shed light into the mechanism of the transformation under study. Additionally, the EcoScale and green metrics of the established protocols were evaluated for benchmarking against some reported methodologies in the literature. [ABSTRACT FROM AUTHOR]

To acquire a further utilization of mulberry seed, antioxidant peptides derived from defatted mulberry seed protein was prepared using a continue-flow microreactor with the synergistic effects of immobilized protease and nontoxic ionic liquid. The mulberry seed meal was pretreated with the combined simultaneous ultrasound treatment at a frequency combination of 20/28/40 kHz, solid–liquid ratio of 1:30, output power of 400 W, and temperature of 40 °C; the extraction rate of mulberry seed protein was up to 70.1%, 21.54% higher than that obtained with the single-frequency ultrasonic treatment (p < 0.05). The hydrolysis process of mulberry seed protein in the continue-flow microreactor was catalyzed by the immobilized protamex combined with choline chloride, the flow rate was 2.5 mL/min, the temperature was 50 °C, and the hydrolysis rate was up to 83.33%, which was 1.14 times higher than that without ionic liquid. Moreover, the immobilized protease can be used 12 times under continue-flow condition, and the enzyme activity was still more than 80% of the original enzyme. Four antioxidant peptides including AMDGK (896.24 Da), KFRAKDG (1109.47 Da), FPSNEPLLG (1287.15 Da), and SNVPNKEL (1005.14 Da) were obtained by ionic liquid-enhanced microfluidic hydrolysis with immobilized protease from mulberry seed protein, and AMDGK had not been reported before. These peptides exhibited strong scavenging activities on 2,2-diphenyl-1-picrylhydrazyl radical (DPPH˙) (EC50 were 2.64, 1.89, 2.16, and 1.34 mg/mL, respectively) and superoxide anion radicals (·O2−) (EC50 were 3.36, 2.78, 2.56, and 1.77 mg/mL, respectively). Thus, the defatted mulberry seed protein possesses good edible development potential and economic value in the production of antioxidant peptides. [ABSTRACT FROM AUTHOR]

With continuous development of pesticide dosage forms, emulsifiable concentrates using large amounts of organic solvents are gradually obsoleted. Nanoemulsions with high water content have been developed and the preparation processes also evolved, but these processes still exist some problems, such as poor controllability and high energy consumption. Microfluidic is a controllable nanoemulsion preparation system which mainly applied to pharmaceutical synthesis. In this study, the pesticide phoxim nanoemulsion was prepared by microfluidic technology. The optimized formulation of phoxim nanoemulsion was composed of Tween 80 and pesticide emulsifier 500 as surfactant, hexyl acetate as oil, and n-propanol as co-surfactant. Moreover, when the flow rates of water and oil in the microfluidic system were adjusted to 5 μL/min and 20 μL/min, phoxim nanoemulsion was obtained with a cloud point/boiling point of 109 °C, a particle size of 21.5 ± 0.8 nm and a potential value of − 18.7 ± 0.6 mV. Furthermore, the nanoemulsion had a rapid release effect in vitro which could be fitted by the Ritger-Peppas model. The feeding toxicity of the phoxim nanoemulsion was higher than that of commercial formulation while the contact killing effect was higher than that of the active ingredient. Therefore, pesticide dosage was reduced and the insecticidal effect was enhanced by using phoxim nanoemulsions. These results also confirm the potential of microfluidics as a green process to produce pesticide nanoemulsions. [ABSTRACT FROM AUTHOR]

This paper presents a high pulse energy, narrow linewidth, mid-infrared (MIR) laser at 6.45 μm, based on a BaGa4Se7 (BGSe) crystal optical parametric oscillator (OPO) pumped by 1.064 μm laser. The maximum pulse energy at 6.45 μm was up to 1.23 mJ, with a pulse width of 24.3 ns and repetition rate of 10 Hz, corresponding to an optical–optical conversion efficiency of 2.1%, from pump light 1.064 μm to idler light 6.45 μm. The idler light linewidth was about 6.8 nm. Meanwhile, we accurately calculated the OPO phase-matching condition at BGSe crystal pumped by 1.064 μm laser, and a numerical simulation system was performed to analyze the input–output characteristics at 6.45 μm, as well as the effect of crystal length on the conversion efficiency. Good agreement was found between measurement and simulation. To the best of our knowledge, this is the highest pulse energy at 6.45 μm, with the narrowest linewidth for any all-solid-state MIR ns laser in BGSe-OPO pumped by simple 1.064 μm oscillator. This simple and compact 6.45 μm OPO system, with high pulse energy and narrow linewidth, can meet the requirements for tissue cutting and improve tissue ablation accuracy. [ABSTRACT FROM AUTHOR]

Optical properties and high-order stimulated Raman scattering (SRS) generation in a homemade CVD diamond crystal with 3 × 3 mm2 aperture are investigated in this paper. The high order of the Raman laser has been studied theoretically and demonstrated experimentally. By simulating the Stokes components at different pump intensities and the divergence angles, the pump source was well matched with the size of the crystal. Pumped by using a 1064 nm picosecond laser, five coaxial wavelengths were obtained for the first time based on the CVD diamond at 932 nm, 1064 nm, 1240 nm, 1485 nm, and 1851 nm. This work provides a reference for further development of the optical grade diamond crystal with a large aperture. [ABSTRACT FROM AUTHOR]

Ways on energy enhancement for single frequency oscillator are reported in this paper. By quantitative analysis on gain and loss coefficients for each cavity mode with inserted etalons, a 37 mJ, 100 Hz high energy single-frequency Nd:YAG oscillator is obtained. The pulse energy is promoted by enhancement of nearly 7 times for a single frequency oscillator reported. The result proves that this method does help for energy enhancement. It has attractive potential for high energy single frequency oscillator design, especially on condition of intensive side pumped or long cavity laser, where strong competitors exist and are hard to be suppressed. [ABSTRACT FROM AUTHOR]

Silkworm pupae are a typical byproduct with high protein content from silk-reeling industry. The aim of this study was to evaluate the performance of defatted silkworm pupae hydrolysate as an alternative nitrogen source to produce polysaccharides and flavonoids using the fungus Phellinus baumii. The results indicated that the defatted silkworm pupa was treated with dispase, and the freeze-dried hydrolysate had a yield of 37% and a nitrogen content of 3.18%. In the fermentation process, the content of the hydrolysates was 32 g/L. Moreover, the consuming reducing sugar accounted for 75.61% of the total reducing sugar and the nitrogen consumption accounted for 35.19% of the total nitrogen content. The maximum biomass produced by the hydrolysate treatment group was 0.6 g/L, and the extracellular flavonoid concentration was 0.4 g/L; the produced extracellular polysaccharide concentration was 7.71 g/L, which was 1.4–5.9 times higher than that of other nitrogen source treatment groups. Therefore, the defatted silkworm pupae hydrolysate is an effective alternative nitrogen source which has great economic value. As a nitrogen source reagent, it enhanced the fermentation ability of P. baumii and increased the yield of extracellular polysaccharides and flavonoids. [ABSTRACT FROM AUTHOR]

The microstructure of Ti-6-4 components produced by additive manufacturing suffers from the coarse and elongated prior-β grain, which leads to a decrease of the tensile behavior and the occurrence of anisotropy. To understand and control the grain evolution, a multiscale simulation is applied to investigate the relationship between the grain selection, growth orientation, and the molten pool morphology with the different deposition layer numbers and processing parameters. The accuracy of the simulation is validated by experiments in both qualitative and quantitative ways. Results show that when the grain with unfavorable orientation loses the competitive growth with its neighbors, there will be a great chance that the blocked grain is eliminated in the following layer-and-layer deposition, which leads to the increase of the grain width. The size of the molten pool increases remarkably as the layer number increases, which lays a heavy burden on the stability of the molten pool. The analytical relationship between the molten pool morphology and the grain growth orientation is also deduced. The flat molten pool causes the grains with the <001> direction close to the building direction to have greater survival potential. Besides, decreasing the line power energy shows little effect on the stability of the molten pool and the grain growth orientation, especially when the deposited layer number is large. The revealing mechanisms will help in understanding and further controlling the grain evolution. [ABSTRACT FROM AUTHOR]

We report on a high-power continuous-wave (CW) intracavity frequency-doubled laser at 670.8 nm, which is produced by the second-harmonic generation of a diode side-pumped Nd:YAP crystal laser with a type-II noncritically phase-matched LBO crystal. A maximum output power up to 13 W at 670.8 nm is obtained with an optical-to-optical (808 nm → 671 nm) efficiency of 2.4%. The beam quality factor M2 is measured to be 8.85, and the fluctuation (RMS) of output power is < ± 0.6% over 30 min. To the best of our knowledge, this is the highest power for the CW laser at 670.8 nm. [ABSTRACT FROM AUTHOR]

Many new techniques and materials have been applied to microfluidic systems in the past decade, and integrated microfluidic chips have become powerful platforms for realizing highly sensitive, high throughput, and low‐cost analysis. This article reviews the latest advancements of microfluidic platforms for biological and biomedical analysis in the fields of fundamental biology research, clinical application, food safety, and environmental monitoring, with a focus on nucleic acid‐based molecular diagnosis and protein‐based immunodiagnosis. The combination of microfluidics with advanced techniques (e.g., nanotechnology, 3D printing, deep learning) would offer innovative new tools for bioanalyses. The current challenges and the future developments of microfluidic technologies for clinical applications are also discussed. It is anticipated that this review will be beneficial to promoting microfluidics toward a broad range of applications in the future. [ABSTRACT FROM AUTHOR]

We briefly review recent results on photoemission spectroscopy based on the deep and vacuum ultraviolet diode pumped solid-state lasers which we have developed. Cascaded second harmonic generation with the nonlinear crystal KBe2BO3F2 (KBBF) is used to generate deep ultraviolet and vacuum ultraviolet laser radiation, which complements traditional incoherent light sources such as gas discharge lamps and synchrotron radiation, and has greatly improved resolution with respect to energy, momentum, and spin of photoemission spectroscopy. Many new functions have been developed with the advantages of high photon energy, narrow linewidth, high photon flux density, and so on. These have led to the observation of various new phenomena and the amassment of new data in the fields of high temperature superconductivity, topological electronics, Fermi semi-metals, and so forth. These laser systems have revived the field of photoemission spectroscopy and provided a new platform in this frontier research field. [ABSTRACT FROM AUTHOR]

The multiwavelength characteristics of stimulated Raman scattering (SRS) in YVO4crystal excited by a picosecond laser at 1064nm are investigated theoretically and experimentally. Laser output with seven wavelengths is achieved coaxially and synchronously at 894, 972, 1175, 1312, 1486, 1713 and 2022nm in a YVO4crystal. The maximum total Raman output energy is as high as 2.77 mJ under the pump energy of 7.75 mJ. A maximum total Raman conversion efficiency of 47.8% is obtained when the pump energy is 6.54 mJ. This is the highest order of Stokes components and the highest output energy generated by YVO4reported up to date. This work expands the Raman spectrum of YVO4crystal to the near-IR regime, with seven wavelengths covered at the same time, paving the way for new wavelength generation in the near-IR regime and its multiwavelength application. [ABSTRACT FROM AUTHOR]

We briefly review the main methods for generating deep ultraviolet (DUV) or vacuum ultraviolet (VUV) light sources, and describe in detail our progress in the design and development of precise and practical DUV all-solid-state lasers based on second harmonic generation. Their incorporation into various kinds of advanced analytic instruments is also discussed. Already, many significant results have been obtained and new phenomena discovered with these state-of-the-art tools. In the last part, we look at possible future developments in the field of DUV/VUV all-solid-state lasers and their potential applications in an even broader range of research fields. [ABSTRACT FROM AUTHOR]

We report on a high pulse energy, narrow-linewidth, Q-switched ultraviolet (UV) laser at 355 nm from the third harmonic generation (THG) of a 1064-nm Nd:YAG master oscillator power amplifier (MOPA) system. An output of 37 W at 355 nm was obtained with a pulse duration of 32 ns and a linewidth of ∼2.5 pm. The beam-quality factor was measured to be $M^{2}$ = 1.24. This is, to the best of our knowledge, the highest average power for a Q-switched narrow-linewidth TEM00 UV laser at 355 nm. Meanwhile, a multimode laser rate equations model was used for theoretical analysis on the linewidth and pulse duration of the fundamental laser oscillator for the first time, and the calculated results agree well with the experimental data. [ABSTRACT FROM AUTHOR]

A high-efficiency picosecond (ps) 532-nm green laser with high pulse energy and high peak power at 5-kHz repetition rate was demonstrated by second-harmonic generation (SHG) from a 1064-nm master oscillator power amplifier (MOPA). The MOPA was based on the Innoslab structure under diode directly pumping, producing 4.8-mJ, 25-ps fundamental laser at the repetition rate of 5 kHz after a three-stage Innoslab amplification system. With a pulse energy of 2.93 mJ in the fundamental and using a type I noncritically phase matched lithium triborate crystal, the pulse energy of SHG was up to 1.96 mJ per pulse with a pulse width of 18.9 ps, which corresponds to a peak power of 104 MW in the green and SH conversion efficiency as high as 67%. The SHG green beam quality factor was measured to be M^2 = 1.75 . [ABSTRACT FROM PUBLISHER]

A widely tunable picosecond midinfrared (MIR) optical parametric amplifier (OPA) with wavelength ranging from 6.4 to 11 \mu \textm based on the BaGa4Se7 crystal was demonstrated. The MIR OPA was pumped by a 30 ps 1064-nm Nd:YAG laser and injected by a KTiOPO4 (KTP)-based narrow-bandwidth widely tunable near-infrared seed. The wide spectral generation using type-I ( \texto\,\,\to \,\, \texte\,\,+\,\,\texte ) critically phase-matched parametric amplification in BaGa4 Se7 was investigated. The output energies were measured to be \sim 38~\mu \textJ at 11 \mu \textm and up to \sim 100~\mu \textJ at 6.4 \mu \textm under pumping energy of $\sim 4.1$ mJ. Further, the type-I phase-matching angles of BaGa4Se7 crystal for idler light generation in the range of 6.4–11 \mu \textm were experimentally measured and the discrepancy between the experiment and theoretical calculation was discussed. [ABSTRACT FROM PUBLISHER]

A total of 56 dried vine fruits, including 31 sultanas and 25 currants, were selected from Chinese markets in 2012. All samples were analysed for Ochratoxin A (OTA) using solid-phase extraction and high-performance liquid chromatography (HPLC) with fluorescence detection. It turned out that 58.9% of the samples were positive and the OTA amount ranged from <0.07 to 12.83 μg/kg, with a mean level of 0.99 μg/kg. Only one sample exceeded the European Union (EU) maximum level of 10 μg/kg. Meanwhile, it was shown that OTA contamination increased among north-western, northern and southern China, which showed OTA means of 0.08, 0.99 and 2.01 μg/kg, respectively. Moreover, in samples of products sold in sealed plastic bags, i.e. consumer-size packages (n = 19, mean = 0.30 μg/kg) less OTA was detected when compared with sampled bulk packages (n = 37, mean = 1.67 μg/kg). In addition, sultanas (mean = 0.92 μg/kg) had less OTA contamination than currants (mean = 1.22 μg/kg). [ABSTRACT FROM PUBLISHER]

Objective: To observe the clinical effect of point application using Chinese herbal medicine for chronic cough in children. Methods: A total of 200 children with chronic cough were randomly allocated into an observation group and a control group, 100 cases in each group. Conventional Western medication was used for cases in the control group, whereas conventional Western medication plus point application using Chinese herbal medicine were used for cases in the observation group. Changes of indexes including eosinophils (EOS), peak expiratory flow (PEF) and forced expiratory volume in one second (FEV) were observed before and after treatment. In addition, the clinical effects were compared between the two groups. Results: After treatment, coughs in children were alleviated in both groups; however, it took a shorter period of time for cough alleviation in the observation group than that in the control group ( P<0.01). On the 28th day of treatment, the EOS, PEF and FEV were improved in both groups ( P<0.01), and the improvements were more significant in the observation group ( P<0.05). Additionally, the frequencies of cough variant asthma attacks were decreased in both groups, but a better effect in the observation group than the control group. Conclusion: Complementary point application using Chinese herbal medicine could substantially improve the clinical effect, alleviate coughs and benefit lung functions. [ABSTRACT FROM AUTHOR]

This paper demonstrated a high power and high beam quality diode-pumped 1319-nm Nd:YAG master oscillator- power amplifier laser system. A thermally near-unstable resonator with four-rod birefringence compensation flat-flat cavity was adopted as the master oscillator. A solid etalon was inserted in the unidirectional ring resonator to compress the laser linewidth. Under a repetition rate of 500 Hz and pulse width of 160 μs, the master oscillator delivers an average output power of 16.8 W at 1319 nm with linear polarisation, beam quality factor M2 = 1.16 and linewidth of 3.2 GHz. A double-pass power amplifier with two amplifier stages was employed for higher power scaling and the output power was amplified to be 25.9 W with M2 = 1.43. [ABSTRACT FROM AUTHOR]

This paper investigates the scattering effect of domestic 0.5 at% ceramic Nd:YAG. An effective method has been utilized to measure the scattering and absorption coefficients. An end-pumped continuous wave (CW) Nd:YAG ceramic laser was also demonstrated. A maximum output power of 6.7 W at 1064 nm was obtained at an 808-nm pump power of 32.9 W. Conversion efficiency and slope efficiency have been achieved. This indicates that scattering has an important effect on the optical performance of ceramic Nd:YAG. [ABSTRACT FROM AUTHOR]

An improved preconditioning scheme incorporating a unified treatment of general fluid thermodynamics is developed for treating fluid flows over the entire regime of fluid thermodynamic states at all speeds. All of the thermodynamic and numerical properties (such as eigenvalues and Jacobian matrices) are derived directly from fundamental thermodynamics theories, rendering a self-consistent and robust algorithm. Further efficiency is obtained by employing temperature instead of enthalpy as the primary dependent variable in the preconditioned energy equation. No iterative solution of a real-fluid equation of state is required. This approach, combined with the use of explicit treatments of temporal and spatial derivatives, results in a scheme for which load balance is much easier to achieve in a distributed computing environment. A numerical stability analysis is performed to assess the effectiveness of the scheme at various fluid thermodynamic states. Sample calculations are also carried out. These include injection and mixing of cryogenic fluids and flame dynamics of coaxial jets of liquid oxygen and methane under supercritical conditions. The robustness and efficiency of the present work are demonstrated over a wide range of thermodynamic and flow conditions. [ABSTRACT FROM AUTHOR]

A compact diode-side-pumped Tm:YAG laser is presented, which can output 51 W of cw power at 2.02mm. The Tm:YAG rod is side pumped by nine diode arrays with the central wavelength of 783nm and the with bandwidth of about 2.5 nm at 25deg C. To decrease the thermal effect on the both ends and dissipate the heat effectively, one composite Tm:YAG rod with the undoped YAG end caps and the screw threads on the side surface of the rod is used as the laser crystal. The maximum optical-to-optical conversion efficiency of the 2.02-mm laser output is 14.2%, with a slope efficiency of 26.8%. [ABSTRACT FROM AUTHOR]

We present 2D-spectroscopic observations from the Centro Astronómico Hispano Alemán 3.5 m telescope and millimeter observations from the NOrthern Extended Millimeter Array of the nearby S0 galaxy PGC 26218, which shows central star formation activity and post-starburst features in the disk. We estimate the star formation rate (SFR = 0.28 ± 0.01 M⊙ yr−1) and molecular gas mass () of PGC 26218 based on the extinction-corrected Hα emission line and the CO–H2 conversion factor (αCO) of the Milky Way, respectively. We find that PGC 26218 follows the star-forming main sequence (SFMS) and the Kennicutt–Schmidt law. Comparing the kinematics of CO(J = 1–0), stars, and Hα, we find that the rotational axis of CO(J = 1–0) is 45° different from that of Hα. In addition, the profile of the CO(J = 1–0) emission line shows asymmetry and has an inflow component of ∼46 km s−1. With the decomposition of the optical image, we confirm that PGC 26218 shows multiple nuclear structures. The projected offset between the most luminous optical center and the center of CO(J = 1–0) is 5.″2 (∼0.6 kpc) and the latter overlaps with one of the optical cores. These results indicate that PGC 26218 may have experienced a gas-rich minor merger, extending its star formation and locating it in the SFMS. [ABSTRACT FROM AUTHOR]

We report a Q-switched 2-mm Tm:YAG laser based on intracavity-pumped by a 1064-nm Nd:YAG laser operating at room temperature for the first time. An average output power of 5.1 W is obtained with the repetition rate of 30 kHz and a pulse width of 300 ns. In addition, we demonstrate a 12.5-W continuous-wave 2-mm Tm:YAG laser, which is, to our best knowledge, the highest power for intracavity-pumping configuration. [ABSTRACT FROM AUTHOR]