Dynamics of submersed aquatic vegetation on shallow soft bottoms in the Baltic Sea

Abstract. Persistence and colonization of submersed aquatic plant species were studied in permanent plots (20 cm × 20 cm) at three shallow sites adjacent to Askö island, in the northern Baltic Sea. The study started in 1991 at two of the sites, in 1992 at a third site and continued until 1997. Two major weather‐induced disturbances occurred during the study: a long, stormy period during a mild winter and a cold winter with extreme low water levels. The stormy period caused a large loss of species from plots (95 ± 5% SE) at the most wave‐exposed site, resulting in a low species number per plot (0.8 ± 0.2) the following summer. During the three following years the mean species number increased to 3.6 ± 0.2. The cold winter caused high species turnover and increased species number per plot at the two most wave‐exposed sites. The species turnover at the sheltered site was highest in the two years with low water level in May, possibly due to increased waterfowl herbivory. Annuals, loosely anchored and highly reproductive species had significantly higher plot colonization rates and lower persistence than perennials, well‐anchored species and species with none or low reproduction. The extent of lateral growth had no significant effect on colonization or persistence. Although these disturbances have a large effect on the dynamics, species mobility was also high in other years. Relative to other, similar, studies in terrestrial vegetation mean persistence in plots was remarkably low and mean mobility and species turnover rates were very high.     

Rapid, concurrent analysis of dopamine, 5-hydroxytryptamine, their precursors and metabolites utilizing high performance liquid chromatography with electrochemical detection: analysis of brain tissue and cerebrospinal fluid

Assays capable of measuring picomole quantities of dopamine (DA), 5-hydroxytryptamine (5-HT), several of their precursors and metabolites concurrently within 25 minutes were developed utilizing high performance liquid chromatography with electrochemical detection (LCEC). Several parameters of the LCEC were altered in order to separate the compounds while maintaining a short assay time. The final LCEC systems demonstrated biological utility in that the DA metabolites, 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA), and the 5-HT metabolite 5-hydroxy-3-indoleacetic acid (5-HIAA) were detected in rat cerebrospinal fluid; in addition to these compounds, DA and 5-HT were measurable in the striatum, hypothalamus and median eminence of the rat brain. Pargyline decreased the concentrations of DOPAC, HVA and 5-HIAA and increased the 5-HT concentration in all three brain regions, and increased the DA concentration in the striatum. Probenecid increased all three acid metabolite concentrations in the hypothalamus and median eminence, while only the HVA and 5-HIAA concentrations were increased in the striatum. The DA and 5-HT concentrations were unaltered. The LCEC methods described in this paper should be useful in elucidating the mechanisms and roles of 5-HT and DA neurons in experimental paradigms of biological interest.     

高阶相对Nie1sen数(Ⅰ)

设f:(X,A)→(X,A)为紧多面体对映射，则高阶相对Nielsen数N~(n）(f;X,A)与NI~（n)(f;X,A)已在[1]中定义，本文在此基础上，给出相对Nielsen数NI~（n)(f;X,A)的估计与计算.     

Tumstatin,a Matrikine Derived from Collagen Type IVα3, is Elevated in Serum from Patients with Non–Small Cell Lung Cancer

OBJECTIVES: Fibrosis and cancer are characterized by extracellular matrix (ECM) remodeling. The basement membrane is mainly composed by collagen type IV and laminin. Tumstatin is a matrix metalloproteinase-9 (MMP-9) generated matrikine of collagen type IV α3 chain. We evaluated the potential of tumstatin as a diagnostic biomarker of lung disorders. METHODS: A monoclonal antibody was raised against the neo-epitope tumstatin. A novel competitive enzyme-linked immunosorbent assay for detection of tumstatin (TUM), was developed and technically characterized. Levels of TUM were measured in serum of patients with idiopathic pulmonary fibrosis (IPF), chronic obstructive pulmonary disease (COPD), and non–small cell lung cancer (NSCLC) belonging to two cohorts. RESULTS: The developed TUM enzyme-linked immunosorbent assay (ELISA) was technically robust. In cohort 1, levels of TUM were significantly higher in NSCLC compared to healthy controls, IPF, and COPD (P = 0.007, P = 0.03 and P = 0.001, respectively). The area under the receiver operating characteristics (AUROC) for separation of patients with NSCLC from healthy controls was 0.97, for separation of NSCLC and IPF patients was 0.98, and for separation of NSCLC and COPD patients was 1.0. In cohort 2, levels of TUM were also significantly higher in patients with NSCLC compared to healthy controls (P = 0.002), and the AUROC for separation of NSCLC and healthy controls was 0.73. CONCLUSIONS: We developed a technically robust competitive ELISA targeting the fragment tumstatin. The level of TUM in circulation was significantly higher in patients with NSCLC compared to patients with IPF, COPD and healthy controls. The assay provided high diagnostic accuracy in separating NSCLC patients from other lung disorders and from healthy controls.