[Effects of simulated acid rain on soil NO emission from typical forest in subtropical sou-thern China].

Based on a long-term simulated acid rain experiment, soil NO emission fluxes were measured using static chambers and the gas chromatography method in a coniferous and broadleaved mixed forest and a monsoon evergreen broadleaved forest in southern China. During the five-year observation periods (2014-2018), soil NO emission fluxes in the two forests showed obvious seasonal variation. The soil NO emission fluxes in wet season were significantly higher than that in dry season, with a large annual variation.

Combination of Amino-Terminal Pro- BNP , Estimated GFR , and High-Sensitivity CRP for Predicting Cardiorenal Syndrome Type 1 in Acute Myocardial Infarction Patients.

Background Cardiorenal syndrome type 1 ( CRS 1) as a complication of acute myocardial infarction can lead to adverse outcomes, and a method for early detection is needed. This study investigated the individual and integrated effectiveness of amino-terminal pro-brain natriuretic peptide (Pro-BNP), estimated glomerular filtration rate (eGFR), and high-sensitivity C-reactive protein (CRP) as predictive factors for CRS 1 in patients with acute myocardial infarction. Methods and Results In a retrospective analysis of 2094 patients with acute myocardial infarction, risk factors for CRS 1 were analyzed by logistic regression.

[Spatial heterogeneity of soil organic carbon and total nitrogen in a monsoon evergreen broadleaf forest in Dinghushan, Guangdong, China].

Geostatistical techniques were used to quantify the spatial heterogeneity of soil organic carbon and total nitrogen of one monsoon evergreen broadleaf forest area in Dinghushan, Guangdong, China. The results demonstrated that a significant spatial autocorrelation existed between soil organic carbon and total nitrogen contents in the Dinghushan monsoon evergreen broadleaf forest, such that 93.6% and 53.

Development of 35 microsatellite markers from heat stress transcription factors in Populus simonii (Salicaceae).

Premise Of The Study: Microsatellite markers within regulators of heat stress transcription factors were identified in the Populus trichocarpa genome, and then developed for P. simonii to investigate the genetic diversity of germplasm resources and to further identify favorable alleles significantly associated with stress-resistant traits.

Methods And Results: Thirty-five novel microsatellite markers were identified from genes controlling heat stress transcription factors in P.

[Characteristics of dominant tree species stem sap flow and their relationships with environmental factors in a mixed conifer-broadleaf forest in Dinghushan, Guangdong Province of South China].

By the method of Granier' s thermal dissipation probe, the stem sap flow density of four dominant tree species (Pinus massoniana, Castanopsis chinensis, Schima superba, and Machilus kwangtungensis) in a mixed conifer-broadleaf forest in Dinghushan Reserve of South China was continuously measured in the dry season (November) and wet season (July) in 2010, and the environmental factors including air temperature, relative humidity, and photosynthetically active radiation (PAR) were measured synchronically, aimed to study the characteristics of the stem sap flow of the tree species in response to environmental factors. During the dry and wet seasons, the diurnal changes of the stem sap flow velocity of the tree species all presented a typical single-peak curve, with high values in the daytime and low values in the nighttime. The average and maximum sap flow velocities and the daily sap flow flux of broad-leaved trees (C.

[Pollution characteristics and source of the atmospheric fine particles and secondary inorganic compounds at Mount Dinghu in autumn season].

Real-time measurements of PM2.5, secondary inorganic compounds in PM2.5 (SO4(2-), NH4(+), and NO3(-)) and related gaseous pollutants were conducted at Mount Dinghu, a regional background station of the Pearl River Delta (PRD), in October and November 2008 by using a conventional R&P TEOM and a system of rapid collection of fine particles and ion chromatography (RCFP-IC).

Development of 15 novel microsatellite markers from cellulose synthase genes in Populus tomentosa (Salicaceae).

Premise Of The Study: Microsatellite markers from cellulose synthase genes were developed for the Chinese white poplar, Populus tomentosa, to investigate the genetic diversity of wild germplasm resources and to further identify favorable alleles significantly associated with wood cellulose content.

Methods And Results: Fifteen microsatellite markers were developed in P. tomentosa by deep sequencing of cellulose synthase genes.

[Effects of elevated CO2 concentration and nitrogen deposition on the biomass accumulation and allocation in south subtropical main native tree species and their mixed communities].

A 5-year experiment was conducted to study the effects of simulated elevated CO2 concentration, nitrogen deposition, and their combination on the biomass accumulation and allocation in five south subtropical native tree species Schima superba, Ormosia pinnata, Acmena acuminatissima, Syzygium hancei, and Castanopsis hystrix and their mixed communities. The test tree species had different responses in their biomass accumulation and allocation to the elevated CO2 concentration and nitrogen deposition. Elevated CO2 concentration and nitrogen deposition increased the biomass of legume species by 49.

[Comparison of treatment with micro endoscopic discectomy and posterior lumbar interbody fusion using single and double B-Twin expandable spinal spacer].

Objective: To compare the therapeutic effect of posterior lumbar interbody fusion by single and double B-Twin expandable spinal spacer with micro endoscopic discectomy (MED) for lumbar intervertebral disc protrusion accompanying degenerative instability.

Methods: From March 2006 to May 2008, 45 patients with lumbar intervertebral disc protrusion accompanying degenerative instability were admitted and managed with posterior lumbar interbody fusion by B-Twin expandable spinal spacer with MED. The patients were randomly assigned to treatment with single B-Twin (Single group, n = 24) or double B-Twin (Double group, n = 21).

[Effects of precipitation intensity on soil organic carbon fractions and their distribution under subtropical forests of South China].

From December 2006 to June 2008, a field experiment was conducted to study the effects of natural precipitation, doubled precipitation, and no precipitation on the soil organic carbon fractions and their distribution under a successional series of monsoon evergreen broad-leaf forest, pine and broad-leaf mixed forest, and pine forest in Dinghushan Mountain of Southern China. Different precipitation treatments had no significant effects on the total organic carbon (TOC) concentration in the same soil layer under the same forest type (P > 0.05).

Homogeneity of delta(15)N in needles of Masson pine (Pinus massoniana L.) was altered by air pollution.

The present study investigated the changes of delta(15)N values in the tip, middle and base section (divided by the proportion to needle length) of current- and previous-year needles of Masson pine (Pinus massoniana L.) from two declining forest stands suffering from air pollution, in comparison with one healthy stand. At the healthy stand, delta(15)N in the three sections of both current- and previous-year needles were found evenly distributed, while at the polluted stands, delta(15)N values in the needles were revealed significantly different from the tip to the base sections.

Direct determination of germanium in botanical samples by graphite furnace atomic absorption spectrometry with palladium-zirconium as chemical modifier.

A method has been described for the direct determination of trace levels of germanium by graphite furnace atomic absorption spectrometry (GFAAS) using chemical matrix modification technique. The stabilization and the pyrolysis temperatures for germanium were investigated with various chemical modifiers including palladium, palladium-magnesium, palladium-strontium and palladium-zirconium. The highest pyrolysis temperature and highest integrated absorbance were obtained using palladium-zirconium modifier, and the severe matrix interference from sulfate can be eliminated.

[Soil organic carbon and nitrogen mineralization along a forest successional gradient in Southern China].

With incubation test, this paper studied the characteristics of organic C and N mineralization in 0-10 cm soil layer under three forest types, i. e., pine (Pinus massoniana) forest (PMF), pine and broad-leaved mixed forest (PBMF) and monsoon evergreen broad-leaved forest (MEBF), which were in a successional series in Dinghushan Mountain of Southern China.

[Simultaneous speciation analysis of arsenic and antimony in traditional Chinese medicines by hydride generation-double channel atomic fluorescence spectrometry].

A method is described for the simultaneous determination of As (III), As (V), Sb (III) and Sb (V) in traditional Chinese medicines by hydride generation-double channel atomic fluorescence spectrometry (HG-AFS). The experimental conditions that influence the fluorescence intensities of arsenic and antimony were investigated and optimized, and the influence of foreign ions and their elimination were studied. The detection limits were found to be 0.

Regeneration of the secondary vascular system in poplar as a novel system to investigate gene expression by a proteomic approach.

Wood formation is a complex process composing many biological events. To access its key developmental stages, we have established a regeneration system that can mimic the initiation and differentiation of cambium cells for Chinese white poplar. Anatomical studies showed that new cambium and xylem re-appeared in sequence within a few weeks after being debarked.

[Clinical research of heart rate turbulence on predictive value in patients with acute myocardial infarction].

Objective: To assess the predictive value of heart rate turbulence (HRT) in patients with acute myocardial infarction.

Methods: One hundred and twenty-five patients with acute myocardial infarction were enrolled in this study. During the period from 6 to 21 days after onset of acute myocardial infarction, they were undergone 24-hour Holter recordings to collect the mean RR interval and heart rate variability (HRV) SDNN.

[Speciation analysis of mercury in traditional Chinese medicine by vapor-generation atomic fluorescence spectrometry].

A sensitive method has been proposed for the determination of inorganic mercury and total organic mercury in traditional Chinese medicine (Wanshi Niuhuang Qingxin) by vapor-generation atomic fluorescence spectrometry. The experimental conditions that influence the atomic fluorescence signal intensity of Hg and the oxidization of organic mercury were investigated and optimized. Thiourea citric acid was selected as a sensitization agent, which greatly enhanced atomic fluorescence signal intensity of mercury.

[Speciation analysis of arsenic in traditional Chinese medicines by hydride generation-atomic fluorescence spectrometry with ion exchange resin separation].

A method for the determination of arsenic species (arsenide, arsenate) in traditional Chinese medicines using hydride generation atomic fluorescence spectrometry (HG-AFS) with ion exchange resin separation has been studied. The ion exchange resin was used to separate the arsenide and arsenate, and the separation conditions were investigated. The experimental conditions that influence the fluorescence intensity and the reduction of arsenic(V) were investigated and optimized, and the influence of foreign ions and its elimination were studied.

[Determination of cadmium in Chinese herbs by atomic absorption spectrometry using atom trapping technique].

A method has been proposed for the determination of cadmium by flame atomic absorption spectrometry (FAAS) using atom trapping technique. The experimental conditions including the flame condition, the trap position, the coolant water flow rate and the collection time, which affected on the absorbance of cadmium, were studied, and the optimum experimental conditions were the acetylene flow rate of 90 L.h-1, the distance of tube from the burner of 5 mm, the distance of tube from the light path of 2 mm and the coolant water flow rate of 1.

Speciation analysis of arsenic in traditional Chinese medicines by hydride generation-atomic fluorescence spectrometry.

A method has been described for the determination of arsenic species (arsenite and arsenate) by hydride generation-atomic fluorescence spectrometry (HG-AFS). The experimental conditions that influence the fluorescence intensity and the reduction of arsenic were investigated and optimized, and the influences from foreign ions and their elimination were studied. The detection limit was found to be 79.

Hydride generation for the direct determination of trace and ultra-trace level of arsenic and antimony in waters using derivative atomic absorption spectrometry.

A new method is developed for the direct determination of trace and ultra-trace level of arsenic and antimony in waters by hydride generation derivative atomic absorption spectrometry (DHGAAS). The signal model and fundamentals of DHGAAS are described. The effects of atomization temperature, argon flow rate, acidity and concentration of KBH(4)and KI were investigated and analytical conditions were optimized.

Determination of mercury in biological tissues by graphite-furnace atomic absorption spectrometry with an in-situ concentration technique.

A method has been described for the determination of total mercury by graphite-furnace atomic absorption spectrometry (GFAAS) using an in-situ concentration technique with a Pd-Zr coating and a chemical modifier. The characteristic mass, which gives an integrated absorbance of 0.0044 s, was found to be 42 pg and an absolute detection limit (3sigma) of 33 pg was obtained with the proposed modifier.