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Photodegradation of the antihistamine cetirizine in natural waters.


Photodegradation of the antihistamine cetirizine in natural waters.

Environ Toxicol Chem. 2014 Jul 18;

Authors: Mead RN, Barefoot S, Helms JR, Morgan JB, Kieber RJ

Abstract
The photodegradation rate of the anti-histamine cetirizine (Zyrtec®) was investigated in various water matrices. The average observed first-order photodegradation rate coefficient (kobs ), obtained by linear regression of the logarithmic-transformed cetirizine concentrations versus irradiation time in simulated sunlight, was 0.024 h(-1) (n = 6; S.D. ± 0.004) in deionized water (DIW) corresponding to a half-life of approximately 30 h. There was no statistical difference in the kobs of cetirizine photodegradation in coastal seawater compared to DIW or in deionized water amended with dissolved chromophoric organic matter. The quantum yield of cetirizine photodegradation decreased dramatically with increasing wavelength and decreasing energy of incoming radiation with the average value ranging from 5.28 × 10(-4) to 6.40 × 10(-3) in the ultraviolet wavelength range (280 nm - 366 nm). The activation energy of cetirizine photodegradation was 10.3 kJ mol(-1) with an observed increase in cetirizine photodegradation as temperature increased. This is a significant environmental factor influencing half-life and an important consideration given cetirizine has been detected in waste water and receiving waters from different locations globally. Environ Toxicol Chem © 2014 SETAC.

PMID: 25044350 [PubMed - as supplied by publisher]

The role of P450 metabolism in the estrogenic activity of bifenthrin in fish


Publication date: Available online 18 July 2014
Source:Aquatic Toxicology

Author(s): Breanna C. DeGroot , Susanne M. Brander

Bifenthrin, a pyrethroid pesticide, is estrogenic in vivo in fishes. However, bifenthrin is documented to be anti-estrogenic in vitro, in the ER-CALUX (estrogen receptor) cell line. We investigated whether metabolite formation is the reason for this incongruity. We exposed Menidia beryllina (inland silversides) to 10 ng/l bifenthrin, 10 ng/l 4-hydroxy bifenthrin, and 10 ng/l bifenthrin with 25μg/l piperonyl butoxide (PBO) - a P450 inhibitor. Metabolite-exposed juveniles had significantly higher estrogen-mediated protein levels (choriogenin) than bifenthrin / PBO-exposed, while bifenthrin alone was intermediate (not significantly different from either). This suggests that metabolites are the main contributors to bifenthrin's in vivo estrogenicity.





High precision photon flux determination for photon tagging experiments


Publication date: Available online 18 July 2014
Source:Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment

Author(s): A. Teymurazyan , A. Ahmidouch , P. Ambrozewicz , A. Asratyan , K. Baker , L. Benton , V. Burkert , E. Clinton , P. Cole , P. Collins , D. Dale , S. Danagoulian , G. Davidenko , R. Demirchyan , A. Deur , A. Dolgolenko , G. Dzyubenko , R. Ent , A. Evdokimov , J. Feng , M. Gabrielyan , L. Gan , A. Gasparian , A. Glamazdin , V. Goryachev , K. Hardy , J. He , M. Ito , L. Jiang , D. Kashy , M. Khandaker , A. Kolarkar , M. Konchatnyi , A. Korchin , W. Korsch , O. Kosinov , S. Kowalski , M. Kubantsev , V. Kubarovsky , I. Larin , D. Lawrence , X. Li , P. Martel , V. Matveev , D. McNulty , B. Mecking , B. Milbrath , R. Minehart , R. Miskimen , V. Mochalov , I. Nakagawa , S. Overby , E. Pasyuk , M. Payen , R. Pedroni , Y. Prok , B. Ritchie , C. Salgado , A. Shahinyan , A. Sitnikov , D. Sober , S. Stepanyan , W. Stevens , J. Underwood , A. Vasiliev , V. Vishnyakov , M. Wood , S. Zhou

The Jefferson Laboratory PrimEx Collaboration has developed and implemented a method to control the tagged photon flux in photoproduction experiments at the 1% level over the photon energy range from 4.9 to 5.5GeV. This method has been successfully implemented in a high precision measurement of the neutral pion lifetime. Here, we outline the experimental equipment and the analysis techniques used to accomplish this. These include the use of a total absorption counter for absolute flux calibration, a pair spectrometer for online relative flux monitoring, and a new method for postbremsstrahlung electron counting.





Effects of MDMA on olfactory memory and reversal learning in rats


Publication date: Available online 10 July 2014
Source:Neurobiology of Learning and Memory

Author(s): Andrew Hawkey , L. Brooke April , Mark Galizio

The effects of acute and sub-chronic MDMA were assessed using a procedure designed to test rodent working memory capacity: the odor span task (OST). Rats were trained to select an odor that they had not previously encountered within the current session, and the number of odors to remember was incremented up to 24 during the course of each session. In order to separate drug effects on the OST from more general performance impairment, a simple olfactory discrimination was also assessed in each session. In Experiment 1, acute doses of MDMA were administered prior to select sessions. MDMA impaired memory span in a dose-dependent fashion, but impairment was seen only at doses (1.8 and 3.0mg/kg) that also increased response omissions on both the simple discrimination and the OST. In Experiment 2, a sub-chronic regimen of MDMA (10.0mg/kg, twice daily over four days) was administered after OST training. There was no evidence of reduced memory span following sub-chronic MDMA, but a temporary increase in omission errors on the OST was observed. In addition, rats exposed to sub-chronic MDMA showed delayed learning when the simple discrimination was reversed. Overall, the disruptive effects of both acute and sub-chronic MDMA appeared to be due to non-mnemonic processes, rather than effects on specific memory functions.





PIH58 Evolution Of The Patient-Centered Concept In The Published Literature


Publication date: May 2014
Source:Value in Health, Volume 17, Issue 3

Author(s): D. Covington , K.M. Veley , H.B. O’Donnell







Assessing source contributions to particulate organic matter in a subtropical estuary: A biomarker approach


Publication date: Available online 9 July 2014
Source:Organic Geochemistry

Author(s): Ding He , Ralph N. Mead , Laura Belicka , Oliva Pisani , Rudolf Jaffé

Assessing the sources and quantifying the contributions of particulate organic matter (POM) in estuaries is a challenge. Here we apply source-specific biomarkers to assess POM sources in an estuary receiving suspended material from freshwater wetlands, fringe mangroves and coastal environments. A three end-member mixing model, including terrestrial, estuarine and marine end-member contributions was developed and successfully validated to assess general organic matter dynamics and hydrologic processes that control POM distributions within the Shark River Estuary in South Florida. Low tide and wet season conditions coincided with an enhanced signal of the freshwater end-member biomarker abundance, while high tide and dry season conditions resulted in enhanced POM input of marine origin. Incoming tide was observed to be an important factor in the re-suspension and tidal pumping of mangrove-derived POM, which seems to be the dominant source of particulate organic carbon (POC) in the estuary. The three end-member conceptual model was tested to obtain a rough estimate of POC source strength, with the ultimate goal of constraining carbon budgets in this sub-tropical estuary. Mangrove-derived POC flux of ca. 5.3 × 105 to 1.0 × 106 kg/yr POC from the Shark River to the Gulf of Mexico were estimated, but end-member values used in the assessment need to be better constrained to reduce the degree of variability.





On the economic determinants of the gold–inflation relation


Publication date: September 2014
Source:Resources Policy, Volume 41

Author(s): Jonathan A. Batten , Cetin Ciner , Brian M Lucey

We examine the long term dynamic relation between inflation and the price of gold. We begin by showing that there is no cointegration between gold and inflation if the volatile period of the early 1980s is excluded from the data. However, we are also able to demonstrate that there is significant time variation in the relation, such that comovement between the variables has indeed increased in the last decade. Examination of the underlying macroeconomic factors that could generate time variation in the gold–inflation linkage suggests gold׳s sensitivity to inflation is related to interest rate changes, a finding that highlights the monetary nature of gold as a commodity.





7-Deoxy-desulfo-cylindrospermopsin and 7-deoxy-desulfo-12-acetylcylindrospermopsin: Two new cylindrospermopsin analogs isolated from a Thai strain of Cylindrospermopsis raciborskii


Publication date: July 2014
Source:Harmful Algae, Volume 37

Author(s): Katie M. Wimmer , Wendy K. Strangman , Jeffrey L.C. Wright

As environmental changes such as eutrophication lead to increased size and frequency of cyanobacterial blooms, research into the toxins produced by these blooms becomes increasingly important. One of the common toxins produced by cyanobacterial blooms is cylindrospermopsin (1), a potent inhibitor of protein synthesis. To date, only two additional analogs of cylindrospermopsin have been isolated, namely 7-epicylindrospermopsin (2) and 7-deoxy-cylindrospermopsin (3). This report details the isolation and structure determination of an additional two new analogs, 7-deoxy-desulfo-cylindrospermopsin (4) and 7-deoxy-desulfo-12-acetylcylindrospermopsin (5). These are the first new analogs of cylindrospermopsin to be reported in over a decade. Based on their structural features, it is likely that these new analogs also possess the harmful biological activities displayed by the rest of the cylindrospermopsin family.





Evidence-Based Knowledge, Skills, and Attitudes for Scholarly Writing Development Across all Levels of Nursing Education


Publication date: Available online 15 November 2013
Source:Journal of Professional Nursing

Author(s): Diane F. Hunker , Elizabeth A. Gazza , Teresa Shellenbarger

Because nursing care in health care settings becomes more complex, nurses are called upon to work effectively with other health care providers to deliver high-quality evidence-based care. To do so in a cost effective and efficient manner requires the development of effective oral and written communication skills in nurses. One form of written communication is scholarly writing. Scholarly writing is defined by the authors as writing that is specialized in nursing, communicates original thought, includes support from a body of literature, contains formal language consistent with the discipline of nursing, and is formatted in a manner consistent with peer-review publications. Faculty who facilitate the development of these skills face inconsistencies in students' writing ability and development across programs and levels of education. Nurse educators need to understand how to develop these communication skills for students enrolled at various educational levels and to teach students how to share information in a scholarly way.





The impact of perceived customer delight on the frontline employee


Publication date: Available online 26 June 2014
Source:Journal of Business Research

Author(s): Donald C. Barnes , Nicole Ponder , Christopher D. Hopkins

A plethora of research has investigated the impact of the frontline employee on the customer, with the consensus that employees can have a tremendous impact on the customer. What remains to be discovered is the extent to which this relationship exists in the reverse. Utilizing broaden-and-build and emotional contagion theories, this study suggests that employee perceptions of a specific customer emotion (delight) have an impact on the frontline employee. Specifically, results from a structural equations model reveal that employee perceptions of customer delight lead to employee positive affect, which in turn positively influences commitment and job satisfaction as well as creates stronger external representation behaviors, internal influence behaviors, and service delivery behaviors from the employee. These findings contribute new evidence to the debate of the viability of providing customer delight and extend our knowledge beyond emotional contagion in explaining how positive customer emotions manifest in employees.





THE IMPACT OF CULTURE ON MARKET TIMING IN CAPITAL STRUCTURE CHOICES


Publication date: Available online 26 June 2014
Source:Research in International Business and Finance

Author(s): Clara Maria Verduch Arosa , Nivine Richie , Peter W. Schuhmann

This study uses Hofstede's (2001) cultural dimensions to investigate the impact of market reception on capital structure. We examine the interaction of these dimensions with stock returns, our proxy for market timing. Based on our market leverage results, we find evidence that firms do engage in market timing by reducing their leverage ratios when their share prices increase. Furthermore, we find that firms in countries with high uncertainty avoidance and high power distance have lower market leverage ratios and that these cultural dimensions serve to reduce the impact of market timing. These results are consistent for developed markets but mixed for emerging markets. On a book leverage basis, the results are generally consistent but less conclusive. To the extent that culture impacts manager perception of risk and investor reception of newly issued shares, we conclude that cultural dimensions impact the degree to which a firm can modify its capital structure to take advantage of perceived market mispricings.





Photochemical dissolution of organic matter from resuspended sediments: Impact of source and diagenetic state on photorelease


Publication date: August 2014
Source:Organic Geochemistry, Volume 73

Author(s): John R. Helms , Donna A. Glinski , Ralph N. Mead , Melissa W. Southwell , G. Brooks Avery , Robert J. Kieber , Stephen A. Skrabal

Sediments exposed to simulated solar radiation release dissolved organic carbon (DOC). However, it is unclear how the provenance of sedimentary organic matter (OM) impacts this photorelease. In the first geographically extensive study of this kind, twenty three size fractionated, fine grained sediments (<ca. 10–20μm) from a variety of drainage basins were resuspended (at suspended solid loading of 29–255mg/l) and exhibited a net photochemical DOC release ranging from 2 to 178μmol/g/h. There was a logarithmic increase in photoreleased DOC vs. the proportion of sedimentary OC (%), most likely resulting from photon limitation at high sedimentary OC loading (i.e. high mass-specific absorption limiting light penetration). Sediment source and quality, as revealed from biomarkers, had a significant effect on DOC photorelease. The fatty acid terrestrial aquatic ratio (TARFA) indicated that terrestrially derived sediments exhibited relatively greater DOC photorelease. The long chain carbon preference index (CPI24–34) indicated that diagenetically unaltered terrestrial OM photoreleased more DOC than diagenetically altered terrestrial OM. The short chain carbon preference index (CPI14–22) demonstrated that sediments containing diagenetically altered planktonic or algal derived OM had a greater photorelease rate of DOC than fresh algal OM. This suggests that humic substances (humus and/or adsorbed humic and fulvic acids) play an important role in the photochemical dissolution of OC regardless of whether or not they are imported from upstream (i.e. terrestrial humics) or generated within the depositional or sedimentary environment (i.e. humification of algal dissolved OM).





Molluscan live–dead agreement in anthropogenically stressed seagrass habitats: Siliciclastic versus carbonate environments


Publication date: 15 September 2014
Source:Palaeogeography, Palaeoclimatology, Palaeoecology, Volume 410

Author(s): Chelsea A. Korpanty , Patricia H. Kelley

Molluscan live–dead fidelity studies investigate the influences of anthropogenic activities on marine ecosystems by comparing the taxonomic composition of a living community to its corresponding death assemblage. Environments subjected to intense anthropogenic stresses tend to yield low fidelity (high discordance) in rank-order abundance and taxonomic similarity between living and dead assemblages. This project assesses the sensitivity of the live–dead approach by applying various fidelity metrics – community richness (Delta-S), evenness (Delta-PIE), rank-order correlation (Spearman rho), and taxonomic similarity (Jaccard–Chao) – to molluscan assemblages in seagrass habitats exposed to anthropogenic stresses in different sedimentary environments. Our study sites include siliciclastic sites in North Carolina, carbonate sites in Florida Bay, and a siliciclastic–carbonate transition locality along the coast of southern Florida. The dominant forms of human stresses at these seagrass sites consist of increased freshwater runoff, increased nutrient runoff, and physical substrate disturbance by dredging (North Carolina) and propeller scarring (Florida Bay). As a result of such anthropogenic stresses, we expected to find low live–dead fidelity results at all of our study sites. We also anticipated variations in the results between sedimentary environments, reflecting intrinsic differences in how molluscan material accumulates and is preserved in siliciclastic versus carbonate settings. Using bulk sediment samples, fidelity analyses consistently yield greater live–dead disagreement at the siliciclastic sites. Despite well-documented historical human stresses to Florida Bay and sediment cores indicating multiple ecological shifts in response to human impacts over time, results from carbonate localities yield higher fidelity and provide little evidence for ecological change. We argue that greater time averaging allows for the death assemblages at the siliciclastic sites to retain a longer memory of the local communities, thus preserving evidence of local ecological changes. In contrast, less time averaging and more rapid live–dead equilibration in carbonate sediments reduces the signal of community changes. Thus we propose that the live–dead fidelity approach is more sensitive at detecting recent ecological changes in siliciclastic versus carbonate environments, confirming the conservative nature of the approach and demonstrating the role of taphonomic bias in live–dead methodology.





The Many Faces of Lipid Rafts


Publication date: 6 May 2014
Source:Biophysical Journal, Volume 106, Issue 9

Author(s): Paulo F. Almeida







Lysylated phospholipids stabilize models of bacterial lipid bilayers and protect against antimicrobial peptides


Publication date: September 2014
Source:Biochimica et Biophysica Acta (BBA) - Biomembranes, Volume 1838, Issue 9

Author(s): Elizabeth Cox , Austen Michalak , Sarah Pagentine , Pamela Seaton , Antje Pokorny

Aminoacylated phosphatidylglycerols are common lipids in bacterial cytoplasmic membranes. Their presence in Staphylococcus aureus has been linked to increased resistance to a number of antibacterial agents, including antimicrobial peptides. Most commonly, the phosphatidylglycerol headgroup is esterified to lysine, which converts anionic phosphatidylglycerol into a cationic lipid with a considerably increased headgroup size. In the present work, we investigated the interactions of two well-studied antimicrobial peptides, cecropin A and mastoparan X, with lipid vesicles composed of 1-palmitoyl-2-oleoyl-phosphatidylcholine (POPC) and 1-palmitoyl-2-oleoyl-phosphatidylglycerol (POPG), containing varying fractions of an aminoacylated phosphatidylethanolamine, a stable analog of the corresponding phosphatidylglycerol-derivative. To differentiate between the effects of headgroup size and charge on peptide–lipid interactions, we synthesized two different derivatives. In one, the headgroup was modified by the addition of lysine, and in the other, by glutamine. The modification by glutamine results in a phospholipid with a headgroup size comparable to that of the lysylated version. However, whereas lysyl-phosphatidylethanolamine (Lys-PE) is cationic, glutaminyl-phosphatidylethanolamine (Gln-PE) is zwitterionic. We found that binding of mastoparan X and cecropin A was not significantly altered if the content of aminoacylated phosphatidylethanolamines did not exceed 20mol.%, which is the concentration found in bacterial membranes. However, a lysyl-phosphatidylethanolamine content of 20mol% significantly inhibits dye release from lipid vesicles, to a degree that depends on the peptide. In the case of mastoparan X, dye release is essentially abolished at 20mol.% lysyl-phosphatidylethanolamine, whereas cecropin A is less sensitive to the presence of lysyl-phosphatidylethanolamine. These observations are understood through the complex interplay between peptide binding and membrane stabilization as a function of the aminoacylated lipid content. This article is part of a Special Issue entitled: Interfacially Active Peptides and Proteins. Guest Editors: William C. Wimley and Kalina Hristova.
Graphical abstract




Membrane-active peptides: Binding, translocation, and flux in lipid vesicles


Publication date: September 2014
Source:Biochimica et Biophysica Acta (BBA) - Biomembranes, Volume 1838, Issue 9

Author(s): Paulo F. Almeida

Recently, new and improved methods have been developed to measure translocation of membrane-active peptides (antimicrobial, cytolytic, and amphipathic cell-penetrating peptides) across lipid bilayer membranes. The hypothesis that translocation of membrane-active peptides across a lipid bilayer is determined by the Gibbs energy of insertion of the peptide into the bilayer is re-examined in the light of new experimental tests. The original hypothesis and its motivation are first revisited, examining some of the specific predictions that it generated, followed by the results of the initial tests. Translocation is understood as requiring two previous steps: binding and insertion in the membrane. The problem of peptide binding to membranes, its prediction, measurement, and calculation are addressed. Particular attention is given to understanding the reason for the need for amphipathic structures in the function of membrane-active peptides. Insertion into the membrane is then examined. Hydrophobicity scales are compared, and their influence on calculations is discussed. The relation between translocation and graded or all-or-none peptide-induced flux from or into lipid vesicles is also considered. Finally, the most recent work on translocation is examined, both experimental and from molecular dynamics simulations. This article is part of a Special Issue entitled: Interfacially Active Peptides and Proteins. Guest Editors: William C. Wimley and Kalina Hristova.
Graphical abstract




The downside of being sexually restricted: The effects of sociosexual orientation on relationships between jealousy, rejection, and anger


Publication date: August 2014
Source:Journal of Research in Personality, Volume 51

Author(s): Jessica R. Peters , Tory A. Eisenlohr-Moul , Richard S. Pond Jr. , C. Nathan DeWall

Why do some people become more jealous than others? Some people require emotional closeness before sexual intercourse, whereas others are less restricted sexually. Because restricted people may invest more in relationships, they may feel greater rejection and anger when jealous. We tested this hypothesis in a daily diary study of 50 heterosexual dating couples. Participants completed a sociosexual orientation questionnaire to measure sexual restriction. Daily partner-related feelings of rejection, jealousy, and anger were assessed for 30days. The more jealousy participants experienced, the greater their feelings of rejection and anger; this relationship was strongest for sexually restricted participants. These findings suggest that sexual restriction may increase risk of feelings of rejection and anger in the wake of jealousy.





What-Where-When memory in the rodent Odor Span Task


Publication date: Available online 13 April 2014
Source:Learning and Motivation

Author(s): Carrie L. Branch , Mark Galizio , Katherine Bruce

While the Odor Span Task (OST) was developed to assess working memory in rodents, it appears that odor (“What”) and time since an odor was last reinforced (“When”) jointly control responding in the OST. The OST uses an incrementing non-match to sample procedure such that the number of stimuli to remember increases during the session; the rodent is trained to remember stimuli within a session but not between sessions. We used a variation of the OST to add a “Where” dimension to the task to examine whether rodents could learn to respond to scents based on contextual cues as well. In Experiment 1, six rats well-trained on the OST procedure were exposed to four target scents in a holding cage before the OST session began [What-Where-When (WWW) condition]. When these target scents appeared in the OST, rats treated them as novel scents despite their being previously encountered that day; WWW responding was comparable to baseline (BL) responding. Controls were implemented to account for relative familiarity: frequency of target presentation and time since the target odor was presented. On both types of control probes, rats typically responded to target scents less than during WWW or BL conditions, took longer to make a response, and visited more comparison stimuli. In Experiment 2, the study was replicated adding reinforcement delivery for responding to pre-session presentation of target stimuli. Subjects were the same six rats plus two additional rats also well-trained on the OST. Results were similar to those from Experiment 1. These data indicate that the variables controlling performance on the OST task include What stimulus is presented, Where (i.e., in which location) it was presented, and When it was presented. Thus, the OST-probe methodology may provide a useful vehicle for the study of episodic-like memory processes in non-humans.





Characterization of carbohydrates in rainwater from the Southeastern North Carolina


Publication date: July 2014
Source:Chemosphere, Volume 107

Author(s): Katherine M. Mullaugh , Jade N. Byrd , G. Brooks Avery Jr. , Ralph N. Mead , Joan D. Willey , Robert J. Kieber

Carbohydrates have been widely reported in atmospheric aerosols, but have not previously been quantified in rainwater. We have identified and quantified a series of 11 specific compounds including monosaccharides (glucose, fructose, arabinose, galactose and pinitol), disaccharides (sucrose and trehalose), sugar alcohols (arabitol, dulcitol and mannitol) and the anhydrosaccharide levoglucosan. Rainwater analyzed in this study includes 52 distinct precipitation events in Wilmington, NC between June 2011 and October 2012. Our analysis indicates carbohydrates typically contribute <1% of total dissolved organic carbon in rain, but can account for as much as 10–35% during periods of high pollen or local fires. Concentrations of individual carbohydrates reached as high as 5.8μM, with glucose and sucrose typically being the predominant species. The distribution of carbohydrates exhibited a distinct seasonal pattern, with higher concentrations of most carbohydrates, especially sucrose, in spring and summer, driven primarily by increased biogenic inputs during the growing season. Concentrations of carbohydrates were an order of magnitude higher in storms of terrestrial origin compared to marine events, further supporting a terrestrial biogenic origin of most species. Sequential sampling of Hurricane Irene showed significant quantities of carbohydrates present at the end of the storm when air mass back trajectories traversed over land. The highest level of levoglucosan, a compound associated with biomass burning, was detected in rain with an air mass back trajectory that traveled over a region affected by wildfires. When compared to aerosol concentrations reported by others, the sugar concentrations in rain demonstrate wet deposition is an important removal mechanism of this water-soluble and bioavailable fraction of atmospheric particulate organic matter.