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The exploitation of multicomponent nanocomposites with suitable hierarchical heterostructures is an attractive strategy to obtain high performance microwave absorption materials. In this work, a versatile strategy is proposed for synthesizing 1D hierarchical core-shell structure with Co-ZIF arrays derived carbon nanotubes (CNTs) coupled on cotton fiber (CF)-supported MXene shell (Co/CNTs-MXene@CF). The advantages of Co-ZIF arrays derived CNTs and MXene dielectric layer can be efficiently integrated to realize multiple electron transfer paths by the construction of the well-designed hierarchical structure. The designed heterogeneous composites consist of the interlayer MXene and CNTs grow sequentially from the outermost Co-ZIF nanosheet arrays with appropriate conductivity and abundant heterointerfaces, which can improve the conduction loss and interfacial polarization response. As expected, the elaborate 1D Co/CNTs-MXene@CF heterostructures exhibit the optimal reflection loss of −61.41 dB at 2.52 mm and effective absorption bandwidth reaches 5.04 GHz with a thickness of only 1.5 mm. The experimental results demonstrate that the optimized structure dramatically improves the electromagnetic wave attenuation behavior. This work illuminates a new design strategy for the preparation of multicomponent composites with reasonable hierarchical structure that enables high-performance microwave absorption materials.

The variable thermophysical properties were introduced into the coupling model of heat transfer and reduction reaction in the Pidgeon process to improve the accuracy of the numerical calculation. The distribution of temperature and magnesium reduction extent in the briquette layer, and the total magnesium reduction extent in the retort were investigated. The model results show better agreement with those of industrial production. The feature of ?layer shift? in the briquette layer during the reduction process was clearly shown. It was shown that the reduction reaction occurs only at a thin interface. The slag layer with lower thermal conductivity of 0.4 W.m-1.K-1 formed during reduction strongly hinders the reaction to move forward within the layers, resulting in the slow magnesium production rate in the Pidgeon process. The improved model can provide a more accurate quantitative prediction for magnesium reduction in the Pidgeon process, which is important for key equipment innovation and the development of new magnesium production techniques.

A new nanoscale architecture of Fe3O4-carbon hybrid materials was developed by a vacuum incipient wetness procedure. The amount of Fe3O4 nanoparticles were controllably confined inside the cavity of the bowl-shaped hollow porous carbon nanocapsules (CNB). TEM images and TG curves proved that different loading of Fe3O4 small nanoparticles (NPs) with a diameter less than 50 nm were stored in CNB. Benefiting from the synergistic effect of the appropriate amount of uniformly dispersed Fe3O4 NPs and bowl-shaped carbon nano-capsules with high specific surface area, high conductivity and high amount of Nitrogen (N) and oxygen (O) elemental doping of Fe3O4@CNB, the new architecture provides good reversibility for the transport of electrolyte ions. When tested in supercapacitor devices, Fe3O4@CNB-2 (containing 40.3 wt% Fe3O4) exhibited the highest gravimetric (466 F g−1) and volumetric capacitance (624 F cm−3). The supercapacitors based on these materials also showed excellent cycling stability (92.4% capacitance retention after 5000 cycles). This class of Fe3O4-carbon hybrid materials has excellent electrochemical properties, and its synthesis strategy can be extended to construct other hybrid materials for various applications, such as biomedicine, catalysis, energy harvest, energy storage and so on.

Photothermal therapy has attracted extensive attentions in cancer treatment due to its precise spatial-temporal controllability, minimal invasiveness, and negligible side effects. However, two major deficiencies, unsatisfactory heat conversion efficiency and limited tissue penetration depth, hugely impeded its clinical application. In this work, hollow carbon nanosphere modified with polyethylene glycol-graft-polyethylenimine (HPP) was elaborately synthesized. The synthesized HPP owns outstanding physical properties as a photothermal agent, such as uniform core-shell structure, good biocompatibility and excellent heat conversion efficiency. Upon NIR-II laser irradiation, the intracellular HPP shows excellent photothermal activity towards cancer cell killing. In addition, depending on the large internal cavity of HPP, the extended biomedical application as drug carrier was also demonstrated. In general, the synthesized HPP holds a great potential in NIR-II laser-activated cancer photothermal therapy. Supplementary Information The online version contains supplementary material available at 10.1186/s12951-021-00884-7.

Low-loss depressed cladding waveguide architecture is highly attractive for improving the laser performance of waveguide lasers. We report on the design and fabrication of the “ear-like” waveguide structures formed by a set of parallel tracks in neodymium-doped yttrium aluminum garnet (Nd:YAG) crystal via femtosecond laser writing. The obtained “ear-like” waveguides are with more symmetric mode profiles and lower losses by systematically comparing the guiding properties of two kinds of normal cladding waveguide. Efficient waveguide lasers are realized based on the designed structure in both continuous wave and pulsed regimes. Combined the high-gain from cladding waveguide and special “ear-like” structure, a passively fundamentally Q-switched laser with the narrow pulse width and the high repetition rate has been obtained by using tin diselenide (SnSe2) as saturable absorber., National Natural Science Foundation of China (12074223, 61775120); China Postdoctoral Science Foundation (2020M682155); Qilu Young Scholar Program; Taishan Scholar Foundation of Shandong Province; Consejería de Educación, Junta de Castilla y León (SA287P18, SA136P20); Ministerio de Economía y Competitividad (FIS2017-87970R).

Resveratrol has been shown to stimulate differentiation of osteoblastic MC3T3-E1 cells in vitro; however, the mechanisms underlying the anabolic effect of resveratrol on osteoblasts remain largely unknown. Our study was aimed to investigate the molecular mechanism of resveratrol-induced differentiation of MC3T3-E1 cells. MC3T3-E1 cells were treated for 8 days with different concentrations of resveratrol (10-8-10-6 M) and 10-6 M cyclosporine A (CsA), a specific inhibitor of the calcineurin/NFAT pathway. According to the results of pilot studies of cell proliferation and alkaline phosphatase activity, 10-7 M concentration of resveratrol was used in subsequent experiments. The levels of mRNA expression of the osteosis-related genes CaN, NFATc1, and Runx2 were analyzed by real-time RT-PCR; the levels of the corresponding proteins were estimated by Western blot analysis. Resveratrol upregulated expression of the CaN, NFATc1, and Runx2 genes at both mRNA and protein levels compared to the control group (p < 0.05), while CsA reduced the effects of resveratrol (p < 0.05). Using immunohistochemical staining, we showed that resveratrol induced NFATc1 accumulation in the cell nuclei, and treatment with CsA inhibited resveratrol-mediated induction of NFATc1, suggesting that the calcineurin/NFATc1 signaling pathway plays an important role in the regulatory effect of resveratrol on osteoblasts.

Colorectal cancer is one of the most common malignant tumors in the world, threatening human health. The treatment strategy of stage II and stage III colorectal cancer has changed from surgery alone to multidisciplinary mode emphasizing perioperative treatment. The indication of adjuvant chemotherapy for stage II colon cancer is still defined by high-risk factors, but only microsatellite status and结直肠癌是最常见的恶性肿瘤之一，极大地威胁着人类的健康。Ⅱ期、Ⅲ期结直肠癌的治疗已经由手术治疗的单一模式转变为强调围手术期的多学科综合诊疗模式。Ⅱ期结肠癌的辅助化疗适应证目前仍以有无临床高危因素来界定，微卫星状态和BRAF基因突变检测对治疗方案的选择有一定的帮助;Ⅲ期结肠癌的辅助化疗以联合化疗为主，疗程为6个月;基于IDEA研究的结果，对T

Heat stable antifungal factor (HSAF) is considered to be a potential biological pesticide due to its broad antifungal activity and novel mode of action. However, few studies have reported on HSAF production during fermentation. Thus, this work was executed to optimize the medium composition to maximize HSAF production by Lysobacter enzymogenes OH11, with soybean flour, glucose and CaCl2 identified as suitable nutrients with concentrations of 8·00, 7·89 and 0·72 g l-1 respectively. Simultaneously, the quantitative analysis of HSAF production was established by eliminating the emulsification problem, and the highest HSAF production was determined to be 356·34 ± 13·86 mg l-1 using the optimized medium, 12-fold higher than when using the 10% TSB medium (29·34 ± 2·57 mg l-1 ). Furthermore, the cost of this medium was assessed and nearly 31-fold lower than that of 10% TSB. This study suggests that the optimized medium is not only effective but also economical for HSAF production. Significance and impact of the study Significance and Impact of the Study: Heat stable antifungal factor (HSAF) exhibits a potent and broad antifungal activity with a novel mode of action. Increased production and reduced cost of raw materials are particularly important for the future production of HSAF, however, no report was involved in these studies. This study aimed to improve the production of HSAF with cheap raw materials through the medium optimization, which would lay the foundation for the application of HSAF in biological control.

Sanjiang Plain is an important grain yield base and ecological demonstration zone of China. Its ecological security, food production, and GDP development can support the sustainable development of SJP. China government focuses on the supply and utilization of resources and grain yield, local government pays attention to the gross domestic product of all sorts of industry, local residents concern the area of paddy and dry lands. This paper takes GDP, grain yield, and ecological service value as our targets under Normal water year and dry year. 8 kinds of land use (dry land, rice (irrigation), rice (rainfed), forest, grassland, wetland, water area, residents), 3 types of industrial development (primary industry, secondary industry, tertiary industry), 3 sorts of water sources (surface water, groundwater, transit water) and 7 ways of water utilization (urban domestic water, rural domestic water, primary industry water, secondary industry water demand, tertiary industry water demand, urban ecological water demand, wetland Ecological water demand) are considered. A comprehensive configuration model of the Sanjiang Plain in the near future (2020) and mid-term future (2025) is presented, which is solved by an optimize software of lingo. The results derived show that the GDP will increase by 50%, the grain output will double, and there is also a slight increase of the ecological service value at 2025.

Room-temperature pulsed and continuous-wave (cw) operation of a tunable external cavity (EC) quantum cascade laser (QCL) at an emitting wavelength of $$4.7\,\upmu \hbox {m}$$ was presented. The effect of different external cavity lengths and grating angles of the EC–QCL system were analyzed numerically. A wide tuning range greater than $$131\,\hbox {cm}^{-1}$$ was obtained in pulsed mode at room temperature. Without the anti-reflection coating procedure, single-mode cw operation with a side-mode suppression ratio (SMSR) above 20 dB and a wide tuning range greater than $$116\, \hbox {cm}^{-1}$$ were achieved. Near the center region, SMSR about 30 dB was also realized through designing the external cavity length. Strain-compensation combined with two-phonon resonance in an active region design and the high-reflection coating promised low threshold current density. A record low threshold current density of $$0.901\,\hbox {kA/cm}^{2}$$ for an EC–QCL operated in cw mode was realized.

Background The profiles of gastroesophageal reflux (GER) and laryngopharyngeal reflux (LPR) in patients with obstructive sleep apnea/hypopnea syndrome (OSAHS) have never been explored. The aim of the study was to investigate the reflux profile in OSAHS patients. Methods Consecutive snoring out-patients suspected with having OSAHS and 20 healthy volunteers were included. All subjects underwent simultaneous 24-h combined multichannel intraluminal impedance–pH (MII–pH) monitoring and polysomnography. Obstructive sleep apnea/hypopnea syndrome was defined when the apnea/hypopnea index was over 5. Stepwise multiple logistic regression analysis was performed to determine the predictor for OSAHS. Key Results Fifty-three patients were included, 37 with and 16 without OSAHS. The prevalence of reflux symptoms was similar between OSAHS (35.1%) and non-OSHAS (37.5%) patients. More OSAHS patients, compared with non-OSAHS patients and healthy volunteers, had pathologic acid GER, nocturnal acid GER, and prolonged acid clearance (P

We demonstrated an all solid-state Nd:GdVO4 Raman laser using LiIO3 as Raman crystal. The maximum output power of 0.645 W was obtained at 1166 nm, corresponding to the conversion efficiency of 8.5%. The Raman laser generated pulse width of 1166 nm as short as 9 ns, which was about four times shorter than that of fundamental light of 1.06 μm. The maximum pulse energy of 62 μJ and the highest peak power of 5.1 kW were achieved with pulse repetition frequency of 5 kHz.

A passively Q-switched and mode-locked Nd:LuVO4 laser with V:YAG at 1.34 μm was successfully demonstrated. Comparisons between c-cut and a-cut Nd:LuVO4 lasers were experimentally made. The maximum average output power of 170 mW, the highest Q-switched pulse energy of 4.5 μJ were obtained in c-cut Nd:LuVO4 laser. The duration of mode-locked pulse was estimated to be less than 540 ps with repetition rate of 110 MHz.

A novel nonlinear frequency conversion process was demonstrated to realize the synchronized dual-wavelength emissions at 1534 and 1572 nm by the mixed optical parametric oscillation (OPO) conversion in gray-tracking-resistance KTP (GTR-KTP) and KTA crystals. Both the two crystals were inserted into the diode-pumped Nd:YAG/Cr4+:YAG fundamental resonator, with their Y axes perpendicular to each other. This could eliminate the competition of the two OPO processes in fundamental radiation. Furthermore, the ratio between the length of GTR-KTP and KTA has also been specially designed to satisfy the same OPO thresholds. The synchronized dual-wavelength lasing with the power ratio of 1:1 between 1534 and 1572 nm was successfully realized. At an incident LD pump power of 7 W, the maximum total output power of 460 mW was achieved, with the corresponding pulse width and repetition rate measured to be 3.9 ns and 5.5 kHz, respectively. This mixed conversion opens a new door for the multi-wavelength lasing.

This paper reported a broadband tuning intracavity optical parametric oscillator (IOPO), based on the multiple grating periodical poled lithium niobate (PPLN) pumped by a acoustic-optical (AO) Q-switched Nd:YVO4 laser. The widely tunable OPO output signal wavelength range from 1390 to 1605 nm, which was obtained by changing PPLN poling period from 27.8 to 31.6 μm at a certain temperature of 46°C, while the continuous tuning range was measured from 1475 to 1592 nm with the PPLN poling period of 30 μm by varying the temperature of nonlinear crystal PPLN from 50 to 120°C. The maximum output power of 0.92 W at 1534 nm with the minimum pulse width of 5.17 ns was generated under the incident pump power of 9.6 W at 808 nm. The corresponding peak power and single pulse energy were calculated to be 5.94 kW and 30.7 μJ, respectively. The M2-factor was measured to be 2.01 at the signal power of 0.4 W.

The simultaneous stimulated Raman scattering (SRS) and optical parametric oscillation (OPO) for the 1064 nm radiation were realized in one KTP crystal for the first time. At an incident diode laser power of 8.6 W, the maximum average output powers at 1096 nm and 1572 nm were 1.1 W and 0.36 W, respectively. The conversion efficiency to Stokes with respect to the incident diode power was as high as 12.8%. The corresponding minimum pulse widths at 1096 nm and 1572 nm were 2.8 and 1.1 ns, respectively.

The efficient dual-wavelength oscillation at 1064 and 1342 nm in the passively Q-switched laser based on Nd:YVO4/V3+:YAG is successfully obtained, as demonstrated in this paper. A total average output power of 2.2 W is obtained with 1.3 W for 1064 nm and 0.9 W for 1342 nm under the incident pump power of 7.7 W, corresponding to a total optical-optical conversion efficiency of 28.2%. The pulse widths are 58 and 54 ns for 1064 and 1342 nm, respectively, with the repetition rate of 89 kHz. Moreover, a rate equation model considering the Gaussian spatial distributions of the intracavity photon density and the initial population-inversion density is presented to characterize the dual-wavelength passive Q-switching operation.

We report a passively mode-locked Yb:Y2Ca3(BO3)4 (Yb:CYB) laser with a partially reflective semiconductor saturable-absorber mirror. The minimum pulse duration of 244-fs with a repetition rate of ~ 55 MHz has been obtained at the central wavelength of 1044.7 nm (8.1 nm full width at half maximum (FWHM)). The measured average output power amounts to 261 mW under the absorbed pump power of 7.0 W. To our best knowledge, this is the first demonstration of a femtosecond Yb:CYB laser.

A simultaneous dual-wavelength eye-safe laser at around 1.9 and 1.7 μm based on only a single KTiOAsO4 (KTA) intracavity optical parametric oscillator (IOPO) is firstly reported. The dual-wavelength-IOPO is driven by an acousto-optic (AO) Q-switched Nd:YAG laser, which is simultaneously oscillated at the radiations of 1.3 and 1.06 μm. Within the KTA-IOPO cavity, the signal output waves of IOPO at the wavelength of 1.9 and 1.7 μm are pumped by the 1.3 and 1.06 μm radiations from Nd:YAG laser, respectively. With the laser diode pumped power of 100 W and the pulse repetition rate of 4 kHz, the maximum average output power of 1.3 W at 1895 nm with the pulse duration of 30 ns and that of 0.9 W at 1715 nm with the pulse duration of 18 ns are obtained. With different diode pump power, the central wavelength of IOPO signal light at 1.9 μm is tunable from 1850 to 1895 nm, while the other signal wave at 1.7 μm is from 1650 to 1715 nm.

The character of a diode-pumped passively Q-switched Nd:GdVO4/V3+:YAG 912 nm laser was demonstrated for the first time to our knowledge. With an absorbed pump power of 7.4 W, an average output power of 360 mW with a Q-switched pulse width of 328 ns at a pulse repetition rate of 163 kHz was obtained. The Q-switching efficiency was found to be 32.7%. Our work further indicated V3+:YAG could be an effective fast passive Q-switch for 0.9 μm radiation.

We report on the generation of continuous wave lasers at a wavelength of ∼1064 nm in a Nd:YAG ceramic waveguide at room temperature. The waveguide was fabricated by using 6 MeV carbon ion implantation at a fluence of 3×1014 ions/cm2. Laser operation has been realized with a slope efficiency as high as ∼11%. The pump threshold of an 808-nm laser beam for the waveguide laser oscillation is 19.5 mW.

The continuous wave (CW) and passively Q-switched Nd:Gd3AlxGa5-xO12 (Nd:GAGG) laser operation at 938 nm have been realized for the first time. The maximum CW output power of 0.44 W was obtained under the absorbed pump power of 8.54 W, corresponding to the slope efficiency of 7.8% and optical-to-optical efficiency of 5.2% respectively. A V3+:YAG saturable absorber crystal with the initial transmission of 97% was used for the passive Q-switching regime. The maximum average output power of 0.19 W was achieved with the minimum pulse width of 358 ns and Q-switched repetition rate of 116 kHz. The corresponding single pulse energy and pulse peak power were determined to be 1.6 μJ and 4.6 W, respectively.

A diode-pumped passively Q-switched Nd:LuVO4 1.34 μm laser using Co:LMA saturable absorber was successfully demonstrated. The average output power, pulse width, repetition rate of a-cut and c-cut Nd:LuVO4 lasers were studied with different output couplers. The maximum average output power of 164 mW was obtained at the pump power of 10.3 W and the narrowest pulse width of 168 ns was achieved at repetition rate of 457 kHz under pump power of 8.59 W in a-cut Nd:LuVO4 laser with T = 8%.

A simple and compact diode-pumped acousto-optically Q-switched intracavity frequency-doubled Nd:LuVO4/KTP green laser were demonstrated successfully for the first time. At an incident pump power of 6.5 W, an average output power of 663 mW, a pulse width of 26 ns were obtained with a PRF of 10 kHz. The pulse energy and peak power of the green light were determined to be 66.3 μJ and 2.55 kW, respectively.

We report an intracavity optical parametric oscillator at 1.57 μm based on non-critically nonlinear crystal KTP driven by an end-pumped acousto-optically Q-switched Nd:LuVO4 crystal. The output characteristics of 1.57 μm were studied with different pulse repetition frequency. The pulse width of 5ns, the maximum peak power and pulse energy of 4.8 kW and 24 μJ were obtained, respectively, with pulse repetition frequency of 5 kHz. The compression ration of pulse width was six times for 1.06 μm to 1.57 μm.

This study was conducted to investigate the variation of monocyte chemoattrant protein-1 (MCP-1) and tissue factor (TF) in elderly patients with acutely exacerbated chronic obstructive pulmonary disease (AECOPD) and their clinical significance.Serum specimens were obtained from 49 AECOPD. Patients and 30 health controls, with mean age of 76.1 ± 10.2 and 62.8 ± 6.5 years. Patients in AECOPD group were further grouped into two subgroups, with high or normal procaletonin (PCT) levels. Plasma TE, MCP-1 and PCT were qualified by enzyme-linked immunosorbent assay (ELISA).TF and MCP-1 were found to be higher in AECOPD patients than in health people (p0.01), and TF was linearly and positively related to MCP-1. In the subgroups TF was significantly higher in patients with higher PCT than those with normal PCT (p0.05).In AECOPD patients blood cells are activated to hypercoagulation state, particularly when their PCT level is high. Extrinsic pathway activated by TE plays important role in development of the hypercoagulation state. Our results indicate that plasma TF level was positively correlated to the level of MCP-1. This suggests that monitoring of plasma TF and MCP-1 levels in AECOPD patients could be a very useful way to prevent and cure blood hypercoagulability, cardiovascular and cerebrovascular thrombotic diseases.

Self-assembled InAs quantum dots (QDs) have been fabricated by depositing 1.6, 1.8, 2.0 and 2.5 monolayer (ML) InAs on surfaces of the undoped-n(+) (UN+) type GaAs structure. Room temperature contactless electroreflectance (CER) was employed to study the built-in electric field and the surface Fermi level pinning of these QD-covered UN+ GaAs samples. The CER results show that 1.6 ML InAs QDs on GaAs do not modify the Fermi level, whereas for samples with more than 1.6 ML InAs coverage, the surface Fermi level is moved to the valence band maximum of GaAs by about 70 meV (which is independent of the InAs deposition thickness) compared to bare GaAs. It is concluded that the modification of InAs coverage on the Fermi level on the GaAs surface is due to the QDs, rather than to the wetting layer. (C) 2003 American Institute of Physics.

The performance of a diode-end-pumped cont- inuous wave (CW) and passively Q-switched Nd:(Lu0.1Gd0.9)3Ga5O12 (Nd:LGGG) laser at 1330 nm were realized for the first time. The maximum CW output power of 0.93 W was obtained under the absorbed pump power of 11 W, corresponding to the slope efficiency of 10.4. By using V3+:YAG crystal as an absorber for passively Q-switching operation, the maximum average output power of 167 mW was generated with the minimum pulsewidth of 15.6 ns and the maximum repetition rate of 10 kHz. The corresponding signal pulse energy and pulse peak power were calculated to be 16.7 μJ and 1.1 kW, respectively.

It has been demonstrated that shared cavity optical parametric oscillator (OPO) could improve power stability in comparison with that of coupled cavity OPO. By theoretically calculating the spectral transmissions induced by the etalon effect, it has been found that the shared cavity OPO had much wider transmission bandwidth than that of coupled OPO. The corresponding experimental results agreed with the theoretical analysis. Furthermore, the OPO and fundamental laser resonator have nearly the same longitudinal mode spacing in the shared cavity configuration. The above two factors can account for the improved performance of the shared OPO operation.

The slip line method has been extended to consider the tangential stress and arbitrary magnitude of wall movement. An analytical solution has also been proposed for the arbitrary mode of wall movement, and the soil mass behind the wall can be homogeneous or layered. The mobilized internal friction angle of the soil and the soil-wall interface friction angle change with the movement of the wall; this has been widely accepted. However, the development of them is not simultaneous. The mobilized friction angles are used in the slip line method and the simplified slip line method to yield the nonlimit lateral earth pressure. Results indicate that earth pressure decreases exponentially with increasing wall movement. Comparisons of the calculated results with measured data and FEM results show that the present analytical method can provide good prediction of the lateral earth pressures and the limit wall movement equal to 0.3%H is appropriate in the calculation (where H is the excavation depth).