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Regulation of water flow by dams for flood control and power generation has changed the patterns of water level fluctuation in the lower Yangtze River. By investigating the branch and leaf traits of M. laxiflora plants at various growth recovery stages along the water fluctuation gradient, this study uncovered the spatiotemporal response in the relationships among branch and leaf traits during growth to the regulated water level fluctuations. Results indicated leaf number (LN) and leaf-and-branch volume (LV) rapidly increased during the first 30 d of growth recovery. Afterwards, the increase in LN gradually slowed, while LV continued to increase steadily and was isometric to the increase in leaf-and-branch dry mass (LM). The investment strategy of this plant species changed from 'fast return' to 'slow return' as plant growth was restored. In the upper hydro-fluctuation zone, the LN vs. LM and leaf-and-branch water content (LWC) vs. LM comparisons exhibited negative allometric growth, while the LV vs. LM comparison exhibited positive allometric growth. In the middle hydro-fluctuation zone, the LN vs. LM and LV vs. LM comparisons exhibited isometric growth patterns, while the LWC vs. LM comparison exhibited positive allometric growth. In the lower hydro-fluctuation zone, the LN vs. LM comparison exhibited positive allometric growth, while the LWC vs. LM comparison exhibited negative allometric growth. As water level decreased, the investment strategies of the plants switched from prioritizing LV and LWC to LN, and shifted from 'slow return' to 'fast return'. The above results indicate that changes in water level fluctuation patterns have greatly affected branch and leaf growth, as well as the growth relationships among branch and leaf traits in the remnant populations of M. laxiflora. Growth of these remnant populations, especially those at the lower hydro-fluctuation zone, was seriously affected and exhibited signs of degradation as a result. Regulation of water flow by dams for flood control and power generation has changed the patterns of water level fluctuation in the lower Yangtze River. The human water flow regulation impacts the allometric growth of M. laxiflora in terms of branch and leaf traits, as well as the investment strategies during growth. Clear differences were observed in the growth patterns of branches and leaves at different levels along the water fluctuation gradient. [ABSTRACT FROM AUTHOR]

Thousand Island Lake (TIL) is a fragmented landscape consisting of more than 1000 land-bridge islands isolated during reservoir formation. To evaluate the effects of fragmentation and island attributes on insect populations, we examined the genetic structure ofLoxoblemmus aomoriensis, a species of cricket widely distributed in TIL, and compared genetic diversity between islands samples. Population genetic analyses was conducted based on mitochondrial DNA haplotype frequencies of 10 sample islands. By comparing three island attributes with population genetic diversity reveals that island area influenced population genetic diversity (r2 = 0.5094,p = 0.00204). Using Pairwise Fst values, we also found that long-distance isolation increased the genetic differentiation, while short-distance isolation can be offset by dispersal. These results indicate that fragmentation can impact populations on a genetic level. [ABSTRACT FROM AUTHOR]

A simple, sensitive, and reliable high performance liquid chromatography (HPLC) method was first developed for simultaneous determination of Ephedrine alkaloids and 2,3,5,6-tetramethylpyrazine (TMP) in Ephedra sinica Stapf. The HPLC separation was performed on a reversed phase C18 column (Nova-Pak® C18, 150 mm × 3.9 mm I.D.) with a duplicate gradient composed of methanol and phosphate buffer solution (PBS, 0.03 mol/L KH2PO4-acetic acid-triethyl amine = 400:0.25:0.1, v:v:v, pH = 6.0) to elute the solutes with a flow rate of 0.8 mL/min. The detection wavelength was set at 210 nm. Regression equations revealed linear relationships (correlation coefficients: 0.991 ∼ 0.998) between the peak area of each constituent (E, PE, NE, NPE, TMP) and its concentration. The detection limits for E, PE, NE, NPE, and TMP were 0.4, 0.1, 0.03, 0.02, 0.03 μg/mL, respectively at a signal-to-noise ratio of 3:1, and the recoveries ranged between 96.0–104.5%. The contents of E, PE, NE, NPE, and TMP in Ephedra sinica Stapf extracts were measured 0.480 g/100 g (2.5%, RSD), 0.090 g/100 g (3.0%, RSD), 0.090 g/100 g (2.4%, RSD), 0.060 g/100 g (2.2%, RSD), and 0.022 g/100 g (1.5%, RSD), respectively. [ABSTRACT FROM AUTHOR]

The main active ingredients, ferulic acid, vanillin, and three senkyunolides in Chinese traditional herb medicine, Chuanxiong, were separated and identified by HPLC, HPLC-MS, and EI-MS. Tetramethylpyrazine (TMP), which was reported as the major active ingredient in Chuanxiong, could not be detected by HPLC in the present paper. Although TMP is the major active ingredient of Chuanxiong, its content was below 1.2×10-7 g/g, which is less than the lower detection limit by HPLC. [ABSTRACT FROM AUTHOR]

A simple, sensitive, and specific high-performance liquid chromatography method has been developed for the simultaneous quantification of the three major biologically active ingredients, gastrodin (GA), 4-hydroxybenzyl alcohol (HA), and 4-hydroxybenzaldehyde (HD), in Gastrodia elata Blume for the first time. The HPLC assay was performed on a reversed phase ODS column by using methanol-water-isopropyl alcohol (35:55:10, v:v:v) as mobile phase with a flow rate of 0.4mL/min. The detection wavelength was set at 270 nm. Regression equations revealed linear relationships (correlation coefficients: 0.9997–0.9999) between the peak area of each constituent (GA, HA, HD) and its concentration. The relative standard deviations of the retention times of three constituents range between 0.2∼0.5%. The recoveries for the three constituents ranged between 96.6∼98.5%. The GA, HA, HD contents measured 12.0 mg/g (2.53% RSD), 2.1 mg/g (2.04% RSD), and 0.13 mg/g (2.63% RSD), respectively, in the ethanol extracts of Gastrodia elata Blume. [ABSTRACT FROM AUTHOR]