378 research outputs found

    Variability of nutrient limitation in the Archipelago Sea, SW Finland

    Get PDF
    Eutrophication is the most acute environmental problem in the Archipelago Sea, SW Finland. When analysing the factors behind this escalating eutrophication the determination of limiting nutrient at a given time is essential. Besides experimentations, nutrient limitation of plankton has been extensively studied by direct chemical analyses. We used the latter approach in this work. Nutrient limitation was studied by calculating different nutrient ratios - total nitrogen:phosphorus, inorganic nitrogen:phosphorus, and nutrient balance ratio. Results showed that phosphorus usually limited primary production only near the coast line. In the middle zone of the Archipelago Sea the limiting factor varied temporally. Outer in the open sea nitrogen limited primary production during most of the year. Phosphorus limited phytoplankton growth especially in spring and in summer and nitrogen in late summer and in autumn. Our results suggested that nitrogen is an important limiting nutrient in the Archipelago Sea. In recent years when the eutrophication has proceeded there has been a shift from.production limitation by both nutrients to limitation by nitrogen alone. But if we want to define and characterize the nutrient limitation of the entire ecosystem of the Archipelago Sea, budgets have to be calculated for both N and P and internal recycling must be taken into account as well as external supply of nutrients and loss processes.</p

    Spatial and temporal representativeness of water monitoring efforts in the Baltic Sea coast of SW Finland

    Get PDF
    Traditional in situ surface water sampling produces accurate information on water chemistry and biology. Such sampling is conducted primarily as part of water quality monitoring programmes. If sufficiently consistent, the once collected water quality data could also provide valuable resources for subsequent use in scientific research and long-term monitoring. We examined the spatial and temporal coherence of the archived data resources stored in the environmental information system of the Finnish Environmental Administration (the Hertta-PIVET register). We used phytoplankton chlorophyll-a and primary productivity data collected during 1971–2006 as sample resources for environmental studies on the highly fragmented SW coast of Finland (Northern Baltic Sea). 733 sampling stations were categorized according to the total number of sampling days, the consistence of sampling, the number of representative years and the continuity of sampling. Considerable spatial and temporal inconsistencies were observed, making the accumulated data resources rather unsuitable for many types of environmental studies. Synchronization of sampling activities could improve the representativeness of spatial and temporal coverage of regional sampling. Strategic planning of sampling is required to achieve more concerted data generation activities and to facilitate long-term spatially representative analyses.</p

    Patterns and dynamics of coastal waters in multi-temporal satellite images: support to water quality monitoring in the Archipelago Sea, Finland

    Get PDF
    The Archipelago Sea in the northern Baltic is a coastal region with A highly dynamic water flow regime, where the need for a methodology to monitor water quality accurately is encountered. In order to contribute to the development of an appropriate strategy to meet this need, the dynamics of the surface waters in the region were analysed using data from six Landsat TM/ETM + images from the late 1990s. Single images were enhanced by principal component transformation and multi-temporal image combination was based on unsupervised classification. The visual patterns discernible in the single images as well as the classification result of the multi-temporal data were compared with the reference data from long-term water quality analyses (Secchi disk depth and chlorophyll-a). The satellite images confirmed dynamic surface flow patterns in the region, indicating gradual and abrupt gradients in water quality, flow directions and forms. These patterns suggest short-term variability in the surface water quality within the region, presenting a challenge for water monitoring. The average Secchi depths increased gradually from the mainland coast until ca. 3-5 in near the open sea. The spatial distribution of chlorophyll-a was found to be more homogeneous, ca. 2-4 mug l(-1). The importance of evaluating the location of an in situ sampling site in relation to the surrounding hydrographic realm is pronounced in regions where field sampling and other monitoring methods remain insufficient in their ability to reflect water quality patterns credibly. In such areas, accurate and cost-effective water quality monitoring and forecasting require an integrated monitoring system, consisting of space and airborne surveillance, field surveys and hydrodynamic modelling. </p

    Human Grasp Assist Device Soft Goods

    Get PDF
    A grasp assist system includes a glove and a flexible sleeve. The glove includes a digit such as a finger or thumb, a force sensor configured to measure a grasping force applied to an object by an operator wearing the glove, and adjustable phalange rings positioned with respect to the digit. A saddle is positioned with respect to the finger. A flexible tendon is looped at one end around the saddle. A conduit contains the tendon. A conduit anchor secured within a palm of the glove receives the conduit. The sleeve has pockets containing an actuator assembly connected to another end of the tendon and a controller. The controller is in communication with the force sensor, and calculates a tensile force in response to the measured grasping force. The controller commands the tensile force from the actuator assembly to tension the tendon and thereby move the finger

    Isotopic consequences of consumer food choice: Hydrogen and oxygen stable isotope ratios in foods from fast food restaurants versus supermarkets

    Get PDF
    a b s t r a c t We investigated geographic trends in the isotopic composition of the modern American diet, purchasing paired food items from fast food restaurants and supermarkets across the USA. We observed large ranges in source of beef available to supermarket patrons. We observed no correlations between the stable isotopic composition of carbohydrates and local tap water. Understanding regional differences observed in some foods but not others will help refine parameters in models used to explore human movements in anthropological, archaeological, and forensic studies

    High-Quality Draft Genome Sequences of Four Lignocellulose-Degrading Bacteria Isolated from Puerto Rican Forest Soil: Gordonia sp., Paenibacillus sp., Variovorax sp., and Vogesella sp.

    Get PDF
    Here, we report the high-quality draft genome sequences of four phylogenetically diverse lignocellulose-degrading bacteria isolated from tropical soil (Gordonia sp., Paenibacillus sp., Variovorax sp., and Vogesella sp.) to elucidate the genetic basis of their ability to degrade lignocellulose. These isolates may provide novel enzymes for biofuel production

    Polymorphism of the FABP2 gene: a population frequency analysis and an association study with cardiovascular risk markers in Argentina

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>The FABP2 gene encodes for the intestinal FABP (IFABP) protein, which is expressed only in intestinal enterocytes. A polymorphism at codon 54 in exon 2 of the FABP2 gene exchanges an Alanine (Ala), in the small helical region of the protein, for Threonine (Thr). Given the potential physiological role of the Ala54Thr FABP2 polymorphism, we assess in this study the local population frequency and analyze possible associations with five selected markers, i.e. glycemia, total cholesterol, body mass index (BMI), hypertension, and high Cardiovascular Risk Index (CVR index).</p> <p>Methods</p> <p>We studied 86 men and 116 women. DNA was extracted from a blood drop for genotype analysis. Allele frequencies were calculated by direct counting. Hardy Weinberg Equilibrium was evaluated using a Chi-square goodness of fit test.</p> <p>For the polymorphism association analysis, five markers were selected, i.e. blood pressure, Framingham Risk Index, total cholesterol, BMI, and glycemia.</p> <p>For each marker, the Odds Ratio (OR) was calculated by an online statistic tool.</p> <p>Results</p> <p>Our results reveal a similar population polymorphism frequency as in previous European studies, with <b>q = 0.277 </b>(95% confidence limits 0.234–0.323). No significant association was found with any of the tested markers in the context of our Argentine nutritional and cultural habits. We did, however, observe a tendency for increased Cholesterol and high BMI in Thr54 carriers.</p> <p>Conclusion</p> <p>This is the first study to look at the population frequency of the Thr54 allele in Argentina. The obtained result does not differ from previously reported frequencies in European populations. Moreover, we found no association between the Thr54 allele and any of the five selected markers. The observed tendency to increased total cholesterol and elevated BMI in Thr54 carriers, even though not significant for p < 0.1 could be worth of further investigation to establish whether the Thr54 variant should be taken into consideration in cardiovascular prevention strategies.</p

    Serum lipid responses to psyllium fiber: differences between pre- and post-menopausal, hypercholesterolemic women

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Cardiovascular disease is the leading cause of death in women and men. Psyllium, a soluble fiber has been known to reduce serum lipids. In this pilot study, we evaluated whether menopausal status would affect the serum lipid responses to psyllium fiber in women.</p> <p>Methods</p> <p>Eleven post-menopausal and eight pre-menopausal women with serum total cholesterol >200 mg/dL were included in the study. Subjects consumed their habitual diet and 15 g psyllium/d for 6 weeks. Psyllium was incorporated into cookies. Each cookie contained ≈5 g of psyllium fiber. Subjects ate one cookie in each meal.</p> <p>Results</p> <p>With psyllium fiber, total cholesterol concentration was significantly lower (≈5.2%, P < 0.05) in post-menopausal women but not in pre-menopausal women (≈1.3%). Also, there was a significant decrease in HDL-cholesterol in post-menopausal women (≈10.2%, P < 0.05). There were no significant changes observed in concentrations of LDL-cholesterol, triglycerides, apolipoprotein A1, and apolipoprotein B in both pre- and post-menopausal women with psyllium.</p> <p>Conclusion</p> <p>In this pilot study, post- and pre-menopausal, hypercholesterolemic women responded differently to psyllium fiber supplementation. Post-menopausal women would benefit from addition of psyllium to their diets in reducing the risk for heart diseases. The results of this study should be used with caution because the study was based on a small sample size.</p
    • …
    corecore