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Jason Tincu, Xenia Water Reclamation Division A small city's wastewater treatment facilities use automatic cell phone reporting to alert operators of problems, avoiding regulatory issues. Many small communities do not [...]

Doxycycline, an antibiotic from the tetracycline class with a broad spectrum of activity, was used to prepare drug delivery systems based on pristine and functionalized mesostructured silica supports. MCM-41-type materials with different textural, structural, and surface properties were used to assess their influence on the drug release kinetics. Small- and wide-angle XRD, FTIR spectroscopy and N2adsorption/desorption isotherms were used to characterize the carriers before and after doxycycline loading. The drug release experiments were performed in vitro in 0.2 M phosphate buffer solution at 37 °C, and the slowest drug release kinetics was obtained for magnesium-modified MCM-41 carrier. All drug-loaded materials exhibited good antibacterial activity against Klebsiella pneumoniaeATCC 10031 strain, similar to the drug alone.

A suite of amphiphilic siderophores, loihichelins A−F, were isolated from cultures of the marine bacterium Halomonassp. LOB-5. This heterotrophic Mn(II)-oxidizing bacterium was recently isolated from the partially weathered surfaces of submarine glassy pillow basalts and associated hydrothermal flocs of iron oxides collected from the southern rift zone of Loihi Seamount east of Hawai’i. The loihichelins contain a hydrophilic headgroup consisting of an octapeptide comprised of d-threo-β-hydroxyaspartic acid, d-serine, l-glutamine, l-serine, l-N(δ)-acetyl-N(δ)-hydroxyornithine, dehydroamino-2-butyric acid, d-serine, and cyclic N(δ)-hydroxy-d-ornithine, appended by one of a series of fatty acids ranging from decanoic acid to tetradecanoic acid. The structure of loihichelin C was determined by a combination of amino acid and fatty acid analyses, tandem mass spectrometry, and NMR spectroscopy. The structures of the other loihichelins were inferred from the amino acid and fatty acid analyses and tandem mass spectrometry. The role of these siderophores in sequestering Fe(III) released during basaltic rock weathering, as well as their potential role in the promotion of Mn(II) and Fe(II) oxidation, is of considerable interest.

Tunichrome Sp-1 is a modified pentapeptide from the ascidian Styela plicata, having the structure H-DOPA-DOPA-Gly-Pro-dcΔDOPA (where DOPA = 3,4-dihydroxyphenylalanine and dcΔDOPA = decarboxy-(E)-α,β-dehydro-DOPA). The tandem mass spectrum of the peptide is dominated by a number of abundant fragment ions that involve a gas-phase rearrangement where the dcΔDOPA group becomes covalently attached to the N-terminus. The high degree of rearrangement in Sp-1 compared with a related octapeptide, plicatamide, allowed for detailed multiple mass spectrometric (MSⁿ) (up to n = 6) experiments, and hence permitted a detailed assessment of the origin and routes to the formation of the various rearrangement ions. Analyses on both a triple-quadrupole and a quadrupole time-of-flight mass spectrometer were made to ascertain whether the gas-phase rearrangements observed for tunichrome Sp-1 were unique to an ion trap mass spectrometer (i.e. the hypothesis being that perhaps the extended trapping times were required to facilitate this unusual gas-phase rearrangement). Interestingly, analyses on both the triple-quadrupole and quadruple time-of-flight mass spectrometers revealed an identical phenomenon, with the rearrangement fragment ions present at approximately the same abundance as the non-rearranged a-, b- and y-type sequence ions. We suggest that the smaller size of tunichrome Sp-1 compared with plicatamide facilitates the transfer of the dcΔDOPA group in this gas-phase rearrangement. This rearrangement was not observed for peptide analogs of tunichrome Sp-1 that did not contain the dcΔDOPA at the C-terminus, confirming that the presence of dcΔDOPA is critical for the rearrangement. Copyright © 2003 John Wiley & Sons, Ltd.

Plicatamide is a modified octapeptide from the ascidian Styela plicata having the structure Phe-Phe-His-Leu-His-Phe-His-decarboxyΔDOPA (where decarboxyΔDOPA = decarboxy-(E)-α,β-dehydro-3,4-dihydroxyphenylalanine). Edman sequencing, tandem mass spectrometry, and proton NMR have been used to characterize 100 μg of the compound. Plicatamide represents an important link between two classes of biomolecules: the tunichromes which share an oxidatively decarboxylated C-terminus and higher molecular weight DOPA-polypeptides. The 8-residue sequence provides the first opportunity to investigate the biosynthetic origins of the tunichrome family by molecular biological techniques.

Clinical characteristics of rotavirus enteritis were evaluated by comparison with acute diarrhea of other etiologies. We reviewed the medical records of children (aged 0–12 months) admitted with acute diarrhea in our hospital between January and December 2011. Of the 839 patients, 49.3 had rotavirus diarrhea. The incidence of severe disease was significantly higher for rotavirus diarrhea (65.2, P< 0.01) than for other types of diarrheal disease.

Nowadays, a better understanding of the factors (including environmental) that influence the degradation of materials from different buildings and monuments, is absolutely necessary. In this paper some analytical techniques, as Fourier Transformed IR Spectroscopy (FTIR), X-ray diffraction (XRD), X-ray fluorescence (XRF), optical microscopy (OM) and SEM-EDS, have been used for evaluation the structure and chemical composition and the characterization of the degradation products, causes and mechanisms of disintegration / degradation of materials and aging processes. Few samples from the Old Gate Tower of the Corvins'Castle, Hunedoara, have been collected and subjected to be analysed and fruitful conclusions have been obtained referring to the raw materials provenance and weathering / deterioration processes which they supported. Similar minerals with those identified at the other towers from Corvins'Castle have been evidenced: quartz, calcite and dolomite, being majority, and additional apatite minerals. Also, ion chromatography could be used to identify the presence of different ions, responsible for the accelerated process of the monument's walls.

The archaeometric study of some samples from New gate Tower from Corvins' Castle are analyzed in this paper in order to identify the raw materials nature and weathering / deterioration processes of these artifacts. Modern analytical techniques, as XRD, FTIR, Raman, SEM-EDS, colorimetry, porosimetry, thermal analysis are used to evaluate the structure and chemical composition (quartz, mica, dolomite, feldspar and plagioclase as albite and microcline minerals). Some minerals similar with apatites have been evidenced being responsible for the consolidated resistance structure inside of the towers.

Circulating tumor cells (CTCs) are cells present in the blood stream during the metastasis process. They can originate from primary or secondary tumors. Circulating tumor cells can be used for early diagnosis or they can be used for prognosis evaluation and even treatment efficiency evaluation. Circulating tumor cells can be captured based on specific antigens found on their surface that differ from those of normal blood cells, they can be captured using specific electrical signatures using dielectrophoresis and they can also be captured using induced magnetic properties and magnetophoresis. In this paper we describe a method for synthesizing and functionalizing superparamagnetic nanoparticles. The nanoparticles will be covered with polyethylenglicol (PEG) molecules to reduce agglomeration and non-specific cell adhesion or blood proteins fouling. The PEG covered magnetic nanoparticles will be functionalized with anti-EpCAM antibodies that are going to make the nanoparticles specifically bind to CTCs present in the blood sample. The samples will be further processed in a microfluidic device that will separate the targeted cells through magnetophoresis.

Graphene is a two-dimensional wonder material, used for electronic and medical applications. To date, various synthesis method of graphene layers is proposed, such as: SiC epitaxial growth, Chemical Vapor Deposition (CVD) and mechanical exfoliation. Graphene single layer can be rapidly produced by CVD. Although the transfer process on different substrates has been researched, a post-processing step after graphene growth for understanding influence of radical of carbon unreacted in graphene properties has not been studied. Deposition of graphene on metal transition substrate involves many reactions, and is not clear what happens with the unreacted methane. The scanning electron microscopy is the best method to visualize this unreacted species as a thin film which covers the graphene layer. The post-processing of graphene after CVD is a crucial step for the performance of graphene-based devices. The graphene film is characterized morphologically and structurally before and after the post-processing step, with the scope of removing the unreacted film and investigating the influence of this step on the graphene properties. To identify the specific vibration of graphene layer before and after post-processing step, Raman spectroscopy has been used. Here, we investigate the quality of CVD graphene before and after removing unreacted hydrocarbon, to better understand the importance of post-processing process for device applications, before the graphene transfer.

A multidisciplinary study on the mortars from the Corvins' Castle, Hunedoara, Romania has been carried out on two ceramic samples which were analyzed through spectral techniques (FTIR, Raman, X-ray powder diffraction) and diverse microscopy techniques (optical, scanning electron microscopy), for determining the chemical, mineralogical and petrographic characteristics on two ceramic tiles coming from the Corvins' Castle discovered during the archaeological campaign from 2012, at the Administrator's House, inside of the castle yard; the results are presented in order to determine the raw material provenance and the production process. Some information on constructive details, construction history and degradation or damage status, are detailed. Also, the diagnosis results aim to determine the damaging causes, as well as the assessment of the safety or the way of intervention on the structure. The archaeometric study of two tiles, including the identifying of the raw materials provenance is important for collecting information about the exploitation of natural resources and to better understand the manufacturing and weathering/deterioration processes of these artifacts. Modern and performant analytical techniques, as FTIR, SEM-EDS, XRD, colorimetric and gloss measurements, are used and the results are discussed too.

A modified pentapeptide has been isolated from the hemocytes of the ascidian Styela plicata. The structure of the peptide was determined by Edman sequence analysis, mass spectrometry, and NMR spectroscopy with the stereochemistry assigned by acid hydrolysis followed by both (a) GC−MS of the volatile amino acid derivatives on a chiral column and (b) ultrasensitive detection of fluorescent diasteromeric derivatives of the component amino acids after reversed-phase HPLC. The peptide l-DOPA-l-DOPA-Gly-l-Pro-dcΔDOPA (where DOPA = 3,4-dihydroxyphenylalanine and dcΔDOPA = decarboxy-(E)-α,β-dehydro-3,4-dihydroxyphenylalanine) we designate as tunichrome Sp-1.

An interview with Jason Tincu, wastewater treatment administrator for Dayton, Ohio is presented. When asked about plans for efficient operations in the long term, he refers to his division's Capital Improvement Program that facilitates infrastructure investment, staff improvement programs, and developing sustainable solutions. He also talks about future challenges to be faced by the city's water treatment plant, and strategies needed to improve its efficiency.