Objective:Cordyceps sinensis (CS) is a popular natural Chinese herbal medicine for invigoration, health preservation and reducing fatigue. Its natural substance has been prepared as a fermentation product of a specifi...Objective:Cordyceps sinensis (CS) is a popular natural Chinese herbal medicine for invigoration, health preservation and reducing fatigue. Its natural substance has been prepared as a fermentation product of a specific strain of Cordyceps sinensis (Cs-4). Our objective was to assess the effect of Cs-4 on the exercise capacity of the healthy elderly people in a randomized, double-blind, placebo-controlled trial. Methods:Thirty-seven healthy, elderly Chinese subjects were randomly assigned to receive either Cs-4 (3 g/ day) or identical placebo capsules. Their exercise performance was tested before and after 6 weeks of treatment with a symptom-limited, incremental work rate protocol on a cycle ergometer. Maximum oxygen uptake (VO2max) was measured using a metabolic chart. Anaerobic thresholds (VO26) were identified by two observers using plots of both VCO2 vs VO2 and VE/VO2 vs time. Results: After taking Cs-4 for 6 weeks, VO2max (1 88±0.13 to 2.00±0 14 L/min; P=0.050) and VO2(1.15±0.07 to 1.30±0.09 L/min; P = 0.012) were significantly increased, whereas after placebo application they were unchanged. Conclusion: These findings support the belief held in China that Cs-4 could improve oxygen uptake or aerobic capacity and ventilation function and resistance to fatigue of elderly people in exercise.展开更多
In this paper,a conventional soliton(CS)mode-locked erbium-doped fiber(EDF)laser was de-veloped using MAX phase material(MAX-PM)Nb_(4)AlC_(3)as a saturable absorber(SA).First,the liquid phase exfoliation(LPE)method wa...In this paper,a conventional soliton(CS)mode-locked erbium-doped fiber(EDF)laser was de-veloped using MAX phase material(MAX-PM)Nb_(4)AlC_(3)as a saturable absorber(SA).First,the liquid phase exfoliation(LPE)method was utilized to prepare Nb_(4)AlC_(3)nanosheets,and then a piece of tapered fiber was adopted to fabricate Nb_(4)AlC_(3)-SA.It was found that the saturation intensity and modulation depth of the Nb_(4)AlC_(3)-SA are 2.02 MW/cm^(2)and 1.88%.Based on the Nb_(4)AlC_(3)-SA,a conventional soliton(CS)mode-locked EDF laser was achieved.The central wavelength,pulse duration,and pulse repetition rate were found to be 1565.65 nm,615.37 fs,and 24.63 MHz,respectively.The performance is competitive and particularly superior in terms of pulse duration.This study fully confirms that Nb_(4)AlC_(3)possesses marvellous nonlinear saturable absorption properties and opens new possibilities for further research on air-stable ultrafast photon-ic devices.展开更多
On the basis of the crystal field theory, the formulae of the EPR g factors of three order perturbation with b 2g ground state for 3d 9/3d 1 ions at rhombic tetrahedral clusters (AX 4) n- have been obtain...On the basis of the crystal field theory, the formulae of the EPR g factors of three order perturbation with b 2g ground state for 3d 9/3d 1 ions at rhombic tetrahedral clusters (AX 4) n- have been obtained. Using these formulae, The authors investigated the EPR g factors of the crystals Cs 2CuCl 4 and T 2CuBr 4. The calculation results agree with the experimental findings.展开更多
文摘Objective:Cordyceps sinensis (CS) is a popular natural Chinese herbal medicine for invigoration, health preservation and reducing fatigue. Its natural substance has been prepared as a fermentation product of a specific strain of Cordyceps sinensis (Cs-4). Our objective was to assess the effect of Cs-4 on the exercise capacity of the healthy elderly people in a randomized, double-blind, placebo-controlled trial. Methods:Thirty-seven healthy, elderly Chinese subjects were randomly assigned to receive either Cs-4 (3 g/ day) or identical placebo capsules. Their exercise performance was tested before and after 6 weeks of treatment with a symptom-limited, incremental work rate protocol on a cycle ergometer. Maximum oxygen uptake (VO2max) was measured using a metabolic chart. Anaerobic thresholds (VO26) were identified by two observers using plots of both VCO2 vs VO2 and VE/VO2 vs time. Results: After taking Cs-4 for 6 weeks, VO2max (1 88±0.13 to 2.00±0 14 L/min; P=0.050) and VO2(1.15±0.07 to 1.30±0.09 L/min; P = 0.012) were significantly increased, whereas after placebo application they were unchanged. Conclusion: These findings support the belief held in China that Cs-4 could improve oxygen uptake or aerobic capacity and ventilation function and resistance to fatigue of elderly people in exercise.
文摘In this paper,a conventional soliton(CS)mode-locked erbium-doped fiber(EDF)laser was de-veloped using MAX phase material(MAX-PM)Nb_(4)AlC_(3)as a saturable absorber(SA).First,the liquid phase exfoliation(LPE)method was utilized to prepare Nb_(4)AlC_(3)nanosheets,and then a piece of tapered fiber was adopted to fabricate Nb_(4)AlC_(3)-SA.It was found that the saturation intensity and modulation depth of the Nb_(4)AlC_(3)-SA are 2.02 MW/cm^(2)and 1.88%.Based on the Nb_(4)AlC_(3)-SA,a conventional soliton(CS)mode-locked EDF laser was achieved.The central wavelength,pulse duration,and pulse repetition rate were found to be 1565.65 nm,615.37 fs,and 24.63 MHz,respectively.The performance is competitive and particularly superior in terms of pulse duration.This study fully confirms that Nb_(4)AlC_(3)possesses marvellous nonlinear saturable absorption properties and opens new possibilities for further research on air-stable ultrafast photon-ic devices.
文摘On the basis of the crystal field theory, the formulae of the EPR g factors of three order perturbation with b 2g ground state for 3d 9/3d 1 ions at rhombic tetrahedral clusters (AX 4) n- have been obtained. Using these formulae, The authors investigated the EPR g factors of the crystals Cs 2CuCl 4 and T 2CuBr 4. The calculation results agree with the experimental findings.
