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A foil that is free to pitch and heave in an upstream flow can oscillate very regularly and with large amplitudes given that its inertial properties and support stiffness in pitch and heave are well adapted to the flow velocity. Useful energy can be extracted from these oscillations via an appropriate damping in heave that models the presence of an electric generator. In recent years, the structural parameters of such a fully passive oscillating-foil turbine (OFT) have been optimized, yielding a maximum energy extraction efficiency of 51.0% under the assumptions of 2D and unconfined flow. However, the turbine is normally deployed in channels with finite cross-sectional area, thus impacting the flow rate passing through the turbine via the blockage effect. In this work, we extend the applicability of the 2D optimized structural parameters to 2D confined scenarios with a simple tuning of the viscous heave damping coefficient. Performance is determined via a fluid-structure interaction solver based on an unsteady Reynolds-averaged Navier–Stokes approach. As expected, confining the turbine increases the heave amplitude and the power, up to a point where the motions become chaotic, and thus require an increase in the heave damping coefficient. This study shows that in all confined 2D scenarios, reasonably good performances of the fully passive OFT can be maintained when using its optimal structural parameters obtained in 2D unconfined conditions, given that the generator is adjusted accordingly. [ABSTRACT FROM AUTHOR]

BACKGROUND/OBJECTIVES: Fatty acids are hypothesized to influence cardiovascular disease risk because of their effect on inflammation. The aim of this study is to assess the relationship between whole-blood fatty acids (WBFAs) and high- sensitivity C-reactive protein (hs-CRP) in European children. SUBJECTS/METHODS: A total of 1401 subjects (697 boys and 704 girls) aged between 2 and 9 years from the IDEFICS (/dentification and prevention of Dietary- and lifestyle-induced health Effects in Children and infantS) study were measured in this cross-sectional analysis. The sample was divided into three categories of hs-CRP. Associations between WBFA and hs-CRP were assessed by logistic regression models adjusting for body mass index (BMI), country, age, breastfeeding, mother's education and hours of physical activity. RESULTS: Linoleic acid (LA) (P = 0.013, 95% confidence interval (CI): 0.822-0.977) and sum of n-6 WBFA (P=0.029,95% CI: 0.866-0.992) concentrations were associated with lower concentrations of hs-CRP in boys. In girls, a high ratio of eicosapentaenoic acid (EPA)/arachidonic acid (AA) was associated (P=0.018, 95% CI: 0.892-0.989) with lower hs-CRP concentrations. In contrast, sum of blood n-6 highly unsaturated fatty acids (P = 0.012, 95% CI: 1.031-1.284), AA (P=0.007, 95% CI: 1.053-1.395) and AA/LA ratio (P = 0.005, 95% CI: 1.102-1.703) were associated (P < 0.05) with higher concentrations of hs-CRP in girls. CONCLUSIONS: The n-6 WBFAs (sum of n-6 FA and LA) were associated with lower hs-CRP in boys and with higher hs-CRP in girls (AA, sum of n-6 highly unsaturated and AA/LA ratio). More studies are needed to identify the optimal levels of WBFAs to avoid low-grade inflammation in children considering the differences by sex and BMI. European Journal of Clinical Nutrition (2016) 70, 819-823; doi: 10.1038/ejcn.2015.219; published online 13 January 2016, INTRODUCTION Low-grade chronic inflammation is related with obesity (1-3) and with the onset and development of atherosclerosis. (1,4) Athero-sclerosis development is characterized by an interaction between vascular endothelial cells and [...]

The past few decades have witnessed an increasing separation of research and teaching, particularly in the area of undergraduate education. Supporters of such a separation have argued that involvement of undergraduates in research is incompatible with the idea of the research university. However, one of the founding principles of the research university, defined by Wilhelm von Humboldt two hundred years ago, is the close partnership of student and faculty in their joint pursuit of research as part of the university function of teaching and learning. In this essay, a concise history of this renowned scholar is provided, leading to a discussion of strategies (with examples) that enable institutions to provide opportunities for undergraduate research in biology, despite the challenges faced by mass higher education and limited resources.

A nanostructured diamond-like carbon (DLC) coated digital versatile disk (DVD) target is presented as a matrix-free sample support for application in laser desorption/ ionization mass spectrometry (LDI-MS). A large number of vacancies, defects, relative [sp.sup.2] carbon content, and nanogrooves of DLC films support the LDI phenomenon. The observed absorptivity of DLC is in the range of 305-330 nm (nitrogen laser, 337 nm). The universal applicability is demonstrated through different analytes like amino acids, carbohydrates, lipids, peptides, and other metabolites. Carbohydrates and amino acids are analyzed as sodium and potassium adducts. Peptides are detectable in their protonated forms, which avoid the extra need of additives for ionization. A bovine serum albumin (BSA) digest is analyzed to demonstrate the performance for peptide mixtures, coupled with the material-enhanced laser desorption/ionization (MELDI) approach. The detection limit of the described matrix-free target is investigated to be 10 fmol/[micro]L for [[Glu.sup.1]]-fibrinopeptide B (m/z 1570.6) and 1 fmol/[micro]L for L-sorbose ([Na.sup.+] adduct). The device does not require any chemical functionalization in contrast to other matrix-free systems. The inertness of DLC provides longer lifetimes without any deterioration in the detection sensitivity. Broad applicability allows high performance analysis in metabolomics and peptidomics. Furthermore the DLC coated DVD (1.4 GB) sample support is used as a storage device for measured and processed data together with sampling on a single device.

Sample pretreaanent is the most important procedure to remove the matrix for interfacing with mass spectrometry (MS). Additionally, for the samples with low concentration, the process of preconcentration is required before MS analysis. We have newly developed a solid-phase extraction stationary phase based on C60-fullerene covalently bound to silica for purification of biomolecules of different characteristics. Silica particles of different porosity are modified with aminopropyl linker and then covalently bound to C60-fullerenoacetic acid or C60-epoxy-fullerenes. The developed materials have been successfully applied as an alternative to commercially available reversed-phase materials for solid-phase extraction. C60-fullerene silica is able to retain small and hydrophilic molecules like phosphopeptides, which can be easily lost by reversed-phase sorbents. The novel materials are applied for desalting and preconcentration of proteins and peptides, especially phosphopeptides. In addition, the C60-fullerene silica is applied for the solid-phase extraction of selected flavonoids with recoveries of ~99%. The recoveries are compared with the commercially available solid-phase extraction materials.

Plates for thin-layer chromatography (TLC) with an attached layer of porous polymer monolith have been prepared and used for the separation of small molecules, peptides, and proteins. The 50-200-[micro]m. thin poly(butyi methacrylate-co-ethylene dimethacrylate) layers were prepared in situ using IN-initiated polymerization. Precise control of the reaction conditions enables the preparation of monolithic layers with a well-defined porous structure that determines the chromatographic performance. Compared to conventional TLC and high-performance TLC using precoated layers based on silica, the small layer thickness and absence of any binder is expected to improve both retention characteristics and separation efficiency of the polymer-based monolithic thin-layer chromatographic plates. Spots of the separated compounds were first detected using typical IN imaging. Since the monolithic thin layers can be also prepared directly on the stainless steel MALDI carder plate, the separation in TLC format can be coupled with MALDI-TOF-MS. Application of a conventional MALDI matrix facilitated desorption and ionization of peptides and proteins for molecular weight determination of the separated compounds.

Six brown ghosts are examined for their use of electric organs in the presence of light, and in the dark. Through a series of bar graphs, the presence of light is determined to affect the frequency of electric discharge.

Capillary electrophoresis and conductometry represent a combination of a high-resolution separation method with a sensitive detection principle for the analysis of ionic species. In this paper, results are reported that are obtained with a contactless conductivity detector. This device works without a galvanic contact of the electrolyte and the electrodes. The conductivity sensor is based on two metal tubes that act as cylindrical capacitors. These electrodes are both placed around a fused-silica capillary with a detection gap of I mm left in between. When a high audio or low ultrasonic oscillation frequency between 40 and 100 kHz is applied to one of the electrodes, a signal is produced as soon as an analyte zone with a different conductivity compared to the background electrolyte passes the detection gap. An amplifier and rectifier is connected to the other electrode where the signal is further processed. Limits of detection for lithium and fluoride are 4 and 13 ppb, respectively, with a linear range over 4 orders of magnitude from 90 ppb up to more than 1000 ppm for both anions and cations. Furthermore, it is demonstrated that for species with lower equivalent conductivities, such as organic ions, indirect conductivity detection is a sensitive alternative to indirect optical detection methods. Limits of detection of 50 ppb and below are obtained for organic acids.

Byline: M. Xie (1), A. von Bohlen (1), R. Klockenkamper (1), X. Jian (2), K. Gunther (3) Keywords: Key wordsaTea leaves; Camellia sinensis; Tea infusions; Multielement analysis; Total- reflection X-ray fluorescence Abstract: aTotal-reflection X--ray fluorescence (TXRF) was used for the simultaneous determination of 15 elements in tea samples which were produced either by acid digestion or acidified infusion of tea leaves (Camellia sinensis). The accuracy and precision of the method were checked by its application to a certified reference material (GBW 08505a:atea). A variety of 39 tea samples of different kinds and/or qualities produced in different regions of China were analysed. The range and mean of the concentrations of elements in the tea leaves (0.1--30.000ugg.sup.--1) and their solubility in infusions (0.5--85%) were determined and the influence of the origin, type and quality of the tea samples was studied. In some tea leaves produced in a Se-rich region, the content of Se was found to be very high (up to 7.5ugg.sup.--1), in contrast to a concentration of only about 0.1ugg.sup.--1 Se in most of the tea leaves examined. Author Affiliation: (1) Institut fur Spektrochemie und Angewandte Spektroskopie, Bunsen-Kirchhoff-Strasse 11, D-44139 Dortmund, Germany, DE (2) Jianshi Institute of Selenium Resources, 445300 Jianshi, Hubei Province, People's Republic of China, CN (3) Institute of Applied Physical Chemistry, Forschungszentrum Julich GmbH, D-52425 Julich, Germany, DE Article note: Received: 27 January 1998

A high-capacity carboxylic acid-functionalized resin prepared by ring-opening metathesis polymerization containing cis-l,4-butanedioic acid (succinic acid) units was used for the extraction of rare-earth elements (REEs) from rock digests. Extraction efficiencies measured by means of ICP-AES were found to be in the range of 90-100% for standards containing 5 and 500 ppb of each REE, respectively. The optimum extraction pH was found to be between 5.3 and 5.5. Three different rock standard reference materials (SRMs), GSR-1 granite, GSR-2 andesite, and GSR-3 basalt, were digested by fusion of the corresponding rock with lithium metaborate (LiB[O.sub.2]) and subsequent dissolution in nitric acid. As a consequence of the different compositions of the three investigated SRMs, the resulting digest showed different concentrations of the REEs as well as of Si[O.sub.2], Fe, Al, Mg, and Ca. The entire extraction procedure was additionally supported by masking of the interfering metal ions using 5-sulfosalicylic acid. Small amounts of methanol were added to prevent silicate from precipitating. Following this setup, REEs occurring in the digest solutions in the range of 40 ppt to 150 ppb were retained selectively, with recoveries ranging for most elements from 75 to 110%. The high performance of the entire system is underlined by the fact that relative standard deviations were < 10% for most of the REEs.

A study was conducted to characterize the preparation of dipyridyl amide-functionalized polymers using ring-opening-metathesis polymerization (ROMP) for the selective extraction of palladium and mercury. Atomic coordinates and equivalent isotropic displacement coefficients were considered in the study. Results showed that the stationary phases supporting the dipyridyl amide ligand prepared by ROMP featured high capacity materials for the enrichment of mercury and palladium out of complex mixtures.

A contactless capacitively coupled conductivity detector for capillary electrophoresis is introduced. The detector consists of two electrodes which are placed cylindrically around the outer polyimide coating of the fused-silica capillary with a detection gap of 2 mm. The electrodes form a cylindrical capacitor, and the electric conductivity of the solution in the gap between the electrodes is measured. A high audio or low ultrasonic frequency for coupling of the ac voltage is used in order to minimize the influence of reactance of the liquid. For an improved version of the detector, two syringe cannulas are used as the electrodes and the capillary is simply assembled into the tubing. This allows an easy placement of the detector on various positions along the capillary. The limit of detection of inorganic cations and anions is 200 ppb, as determined for sodium and chloride, respectively.

Modern separation techniques require high-performance materials, and solid-phase extraction (SPE) is important in sample clean-up and analyte peconcentration in analytical chemistry. A new approach to SPE materials was developed, based on a ring-opening-metahesis polymerization (ROMP) technique. This led to predeterminable, predictable and reproducible stationary phases and materials that were stable over the whole pH range.

Gel filtration chromatography and circular dichroism were utilized to determine the association-dissociation kinetics of S461L and S324L oligomer-forming C-fragments. The slow introconversion between oligomers and monomers is characterized by the unfolding of the intermolecular coiled coils in the C-fragment of the oligomers. The temperature dependent association-dissociation by S461L and S324L produces a transition-state that is similar to an unfolded protein.

Ion-pair reversed-phase high-performance liquid chromatography on nonporous alkylated poly(styrene-divinylbenzene) particles allowed the separation of double-stranded DNA fragments in a few minutes with a resolution comparable to that obtained in slab or capillary gel electrophoresis. Using gradients of acetonitrile in 0.1 M triethylammonium acetate, DNA fragments differing in length only by 2-3% could be resolved. Synthesis of the stationary phase was very reproducible, and equilibration of a freshly packed column for at least 2 h proved to be necessary for optimum column performance, whereas column regeneration for 1-5 min was adequate between gradient runs. Various DNA molecular weight markers ranging from 51 to 2176 base pairs in length were used to study the size dependence of retention. A plot of capacity factors versus logarithm of molecular weights revealed a clear correlation between size and retention. Both a local and a global approximation method, which differed with regard to the number of known standard fragments used below and above the fragments with unknown length to create a sizing curve based on simple linear regression, gave essentially identical results, with the inaccuracy of length measurement being 0.05-3.2%. This compares favorably with the accuracy obtained in gel electrophoresis.