Ni-30wt%Sn alloy powder beds were remelted using a laser beam to examine regular eutectic and anomalous eutectic growth behavior. The remelted microstructure mainly consisted of primary α-Ni ...dendrites and refined regular lamellar eutectic in the interdendrite space. At the top of the molten pool, the competition between primary α-Ni dendrites and the regular lamellar eutectic can be explained by the maximum interface temperature criterion. Anomalous eutectic was observed at the bottom of the molten pool. The remelting of primary α-Ni dendritic arms formed in the first laser remelting scan had an important effect on the formation of the anomalous eutectic in the second laser remelting scan. This effect led to the formation of globular α-Ni particles with similar Euler's angles in the anomalous eutectic.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
In this work, a highly sensitive method using a colorimetric probe coupled to dispersive liquid–liquid microextraction (DLLME) was developed for the quantitative determination of dopamine (DA) in ...serum. The DA in serum was concentrated by DLLME to increase the detection sensitivity and reduce the matrix effects. After the DLLME process, a colorimetric probe of silver triangular nanoparticles (AgTNPs) was used to detect DA, which was based on the plasma transformation of AgTNPs caused by strong interactions with melamine (MA). The results showed that DA could inhibit the aggregation of AgTNPs induced by MA, resulting in the recovery of the surface plasmon resonance (SPR) peak of AgTNPs. Thus, the DLLME method followed by colorimetric probe detection of DA can be achieved. The parameters affecting the proposed method were optimized, under the optimal conditions, a linear calibration curve was obtained over a concentration range of 5 to 250 nM with a recovery from 94.4 to 101.3%. The detection limit was 1.6 nM (at an S/N ratio of 3). The present method was successfully applied to determine DA in human serum.
Schematic illustration of the DA detection mechanism.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Laser remelting has been performed on Ni-30 wt.% Sn hypoeutectic alloy. An anomalous eutectic formed at the bottom of the molten pool when the sample was remelted thoroughly. 3D morphologies of the ...α-Ni and Ni
3
Sn phases in the anomalous eutectic region were obtained and investigated using serial sectioning reconstruction technology. It is found that the Ni
3
Sn phase has a continuous interconnected network structure and the α-Ni phase is distributed as separate particles in the anomalous eutectic, which is consistent with the electron backscatter diffraction pattern examinations. The α-Ni particles in the anomalous eutectic are supersaturated with Sn element as compared with the equilibrium phase diagram. Meanwhile, small wavy lamella eutectics coexist with anomalous eutectics. The Trivedi-Magnin-Kurz model was used to estimate undercooling with lamellar spacing. The results suggest that the critical undercooling found in undercooling solidification is not a sufficient condition for anomalous eutectic formation. Besides, α-Ni particles in the anomalous eutectic do not exhibit a completely random misorientation and some neighboring α-Ni particles have the same orientation. It is shown that both the coupled and decoupled growth of the eutectic two phases can generate the α-Ni + Ni
3
Sn anomalous eutectic structure.
This study aimed to explore the therapeutic effect and potential mechanism of heparin-binding protein (HBP) reduction on sepsis-related acute lung injury.
We utilized a murine model of sepsis-induced ...by intraperitoneal injection of lipopolysaccharides (LPS) in C57BL/6J mice divided into four groups: Control, LPS, Anti-HBP, and ceftriaxone (CEF). Following sepsis induction, Anti-HBP or CEF treatments were administered, and survival rates were monitored for 48 h. We then used reverse-transcription quantitative PCR to analyze the expression levels of HBP in lung tissues, immunohistochemistry for protein localization, and Western blotting for protein quantification. Pulmonary inflammation was assessed using enzyme-linked immunosorbent assays of proinflammatory cytokines (tumor necrosis factor-α, interleukin IL-1β, IL-6, and interferon-γ). The activation state of the aryl hydrocarbon receptor (AhR) signaling pathway was determined via Western blotting, evaluating both cytoplasmic and nuclear localization of AhR and the expression of cytochrome P450 1A1 protein by its target gene.
Anti-HBP specifically reduced HBP levels. The survival rate of mice in the Anti-HBP and CEF groups was much higher than that in the LPS group. The severity of lung injury and pulmonary inflammatory response in the Anti-HBP and CEF groups was significantly lower than that in the LPS group. AhR signaling pathway activation was observed in the Anti-HBP and CEF groups. Additionally, there was no significant difference in the above indices between the Anti-HBP and CEF groups.
HBP downregulation in lung tissues significantly improved LPS-induced lung injury and the pulmonary inflammatory response, thereby prolonging the survival of sepsis mice, suggesting activation of the AhR signaling pathway. Moreover, the effect of lowering the HBP level was equivalent to that of the classical antibiotic CEF.
Not applicable.
Protected areas have become important tourism products that promoted as attractions by the tourism industry. Taking the Changbai Mountain Biosphere Reserve in Northeast China as a case, this study ...addresses visitor needs as a basis for developing a tourism strategy aimed at enhancing tourist opportunities at this reserve. A factor-cluster approach was employed to identify visitor segment profiles based on their visit motivations. Through random sampling, a pencil-and-paper questionnaire in Chinese language was collected from 637 domestic tourists in the study area. A principal components analysis of motivations revealed eight motivational factors, and four distinct groups of tourists–Nature travelers, Cultural landscape tourists, Food & shopping enthusiasts, and Eclectic adventurers–were identified. Understanding the differences in these visitor segments will help the management authority effectively analyze nature reserve attributes and provide alternative activities and services to tourists. Finally, within the dual framework of market segmentation and destination management some management recommendations and marketing implications are suggested.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
In this study, a series of curcumin derivatives containing 1,2,3‐triazole were designed and synthesized, and their inhibitory activities against the proliferation of lung cancer cells were studied. ...Compound 5 k (3,4‐dichlorobenzyltriazole methyl curcumin) had the best activity against A549 cells, with a half‐maximal inhibitory concentration (IC50) of 2.27 μM, which was approximately 10 times higher than that of the lead curcumin and higher than that of gefitinib (IC50=8.64 μM). Western blotting revealed that 5 k increased the phosphorylation levels of p38, c‐Jun N‐terminal kinase (JNK), and extracellular signal‐regulated kinase (ERK). Compound 5 k also promoted the expression of the inhibitor of nuclear factor‐κB (IκBα) and decreased that of nuclear factor‐κB (NF‐κB), signal transducer and activator of transcription 3 (STAT3), and β‐catenin. Therefore, 5 k suppresses A549 cell proliferation by activating the mitogen‐activated protein kinases and suppressing NF‐κB/STAT3 signaling pathways. So, 5 k can potentially be used for treating non‐small cell lung cancer.
Breathe easy as 1,2,3: A novel series of triazole curcumins was designed and synthesized by introducing 1,2,3‐triazole into the active methylene of curcumin. The generated dichloro‐substituted phenyltriazole methyl curcumin effectively inhibited tumor cell proliferation and induced cell death against lung cancer cells both in vitro and in vivo, and may thus be a potential drug for the treatment of non‐small cell lung cancer.
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A diode-end-pumped Nd:LGGG dual-wavelength synchronously mode-locked laser operation at 1.06 μm was demonstrated. The maximum average output power of 475 mW was obtained. The two wavelengths were ...simultaneous mode-locked at 1060.9 and 1062.7 nm with the pulse duration of 6.3 ps. A laser frequency beat was observed on top of the autocorrelation trace in the operation, corresponding to the 0.48 THz signal of stationary wave interference pattern.
A systematic study of the spectral properties and ultrafast lasing characteristics of Yb:(Lu x Gd 1-x ) 3 Ga 5 O 12 (x = 0.062) (Yb:LGGG) disordered crystal was reported for the first time. The broad ...fluorescence spectral lines indicate a great potential of Yb:LGGG for tunable and ultrafast laser application. In the lasing experiment, a passively mode-locked Yb:LGGG laser was realized, which generated a maximum average power of 1.3 W with pulse duration of 324 fs at the central wavelength of 1029.6 nm, corresponding to a slope efficiency as high as 41.6%. The pulse energy and peak power were calculated to be 22.4 nJ and 69.2 kW. By optimizing the cavity design, the shortest pulse duration of 188 fs was achieved at the central wavelength of 1026.8 nm. In this case, the maximum average output power of 0.77 W was generated with a slope efficiency of 27.1%. The experimental results show the excellent potential of Yb:LGGG crystal for high-efficiency and high-peak-power femtosecond laser.
The effect of the heating rate on the nucleation of metallic glass in a rapid heating process starting from the glass transition temperature is investigated. The critical nucleus radius increases ...with the increase of the temperature of the undercooling liquid. If the increment rate of the critical nucleus radius, owing to the heating process, is higher than the growth rate of the nuclei, the nuclei generated at the low temperature will become the embryos at the high temperature. This means that the high heating rate can make no nucleation happen in the heating process. In consideration of the interfacial energy, the growth rate of the nuclei increases with the increase of their size and the growth rate of the critical nucleus is zero. Thus, the lower heating rate can also make the nuclei decline partially. Finally, this theory is used to analyze the nucleation process during laser remelting metallic glass.
•High-quality graphene oxide saturable absorber was successfully fabricated with 1–2 layer graphene oxide.•Femtosecond pulse generation from a graphene oxide mode locked bulk laser was demonstrated ...for the first time.•The results present here indicate that GO is a promising saturate absorber material for femtosecond bulk laser.
High-quality graphene oxide saturable absorber (SA) is successfully fabricated with 1–2 layer graphene oxide. By employing this SA, we have demonstrated femtosecond pulse generation from a graphene oxide passively mode locked bulk laser for the first time to our best knowledge. With two Gires–Tournois interferometer mirrors for dispersion compensation, pulses as short as 493fs with an average power of 500mW are obtained at the central wavelength of 1035.5nm. These results presented here indicate the great potential of GO for generating femtosecond mode-locked pulses in the bulk laser.
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