bluuebunny/crossref_metadata_2025 huggingface dataset:
Deposition Mechanisms in Layer-by-Layer or Step-by-Step Deposition Methods: From Elastic and Impermeable Films to Soft Membranes with Ion Exchange Properties
Authors: Michel Marc , Toniazzo Valérie , Ruch David , Ball Vincent
Published: March 2012

The modification of solid-liquid interfaces with polyelectrolyte multilayer films appears as a versatile tool to confer new functionalities to surfaces in environmentally friendly conditions. Indeed such films are deposited by alternate dipping of the substrates in aqueous solutions containing the interacting species or spraying these solutions on the surface of the substrate. Spin coating is more and more used to produce similar films. The aim of this short review article is to provide an unifying picture about the deposition mechanisms of polyelectrolyte multilayer films. Often those films are described as growing either in a linear or in a supralinear growth regime with the number of deposited “layer pairs”. The growth regime of PEM films can be controlled by operational parameters like the temperature or the ionic strength of the used solutions. The control over the growth regime of the films as a function of the number of deposition steps allows to control their functional properties: either hard and impermeable films in the case of linear growth or soft and permeable films in the case of supralinear growth. Such different properties can be obtained with a given combination of interacting species by changing the operational parameters during the film deposition.
Clinical and Electrocardiographic Evaluation of Sickle-Cell Anaemia Patients with Pulmonary Hypertension
Authors: Oguanobi N. I. , Ejim E. C. , Anisiuba B. C. , Onwubere B. J. C. , Ike S. O. , Ibegbulam O. G. , Agwu O.
Published: March 2012

Pulmonary hypertension is an emerging complication of sickle cell anaemia with associated increased risk of mortality. In order to evaluate the clinical and electrocardiographic findings in adult sickle-cell patients with pulmonary hypertension, a cross sectional study was conducted on sixty two sickle cell anaemia patients and sixty two age and sex matched normal controls. Elevated pulmonary artery pressures (PAP), defined by PAP ≥ 30 mm Hg on echocardiography, was demonstrated in 41.9% of patients with sickle cell anaemia and in 3.2% of the controls; , . Right ventricular hypertrophy, increased P-wave duration, QTc interval, and QTc dispersion were significantly associated with pulmonary hypertension. Significant correlation was found between mean PAP and (1) Frequency of crisis (Spearman correlation = 0.320; ), (2) body mass index (Pearson’s correlation = −0.297; ), and (3) QTc interval (Pearson’s correlation 0.261; ). Pulmonary hypertension in adult sickle anaemia patients is associated with electrocardiographic evidence of right ventricular hypertrophy, and correlates significantly with frequency of vaso-occlusive crisis, and QTc interval. The observations by this study tend to suggest that these parameters could be useful for early detection and prevention of pulmonary hypertension in patients with sickle cell anaemia.
Application of Ion-Association Titration for the Assay of Cyproheptadine Hydrochloride in Pharmaceuticals
Authors: Raghu Madihalli S. , Basavaiah kanakapura
Published: March 2012

Two simple and rapid titrimetric methods are described for the determination of cyproheptadine hydrochloride (CPH) in pharmaceuticals. The proposed methods are based on the solvent extraction-titration of CPH with two ion association reagents, sodium lauryl sulphate (SLS), (method A), and tetraphenylborate (TPB), (method B). In method A, SLS was used as titrant and the titration was carried out in the presence of dilute sulphuric acid and chloroform using dimethyl yellow as indicator, whereas, in method B, the titrant was TPB and the titration was done in Walpole buffer of pH 4.5 and 1, 2-dichloroethane using tetrabromophenolphthalein ethyl ester as indicator. The proposed procedures give sharp end points as the color of the organic phase changes from yellow to pink in method A, and from red-violet to yellow in method B. The methods are applicable over the ranges of 1.0–20.0 and 2.0–9.0 mg of CPH for method A and method B, respectively. The accuracy and precision of the methods are good. The methods were applied successfully to the determination of CPH in tablets, and the results were in agreement with the label claim and those of the reference method.
Direct Electron Transfer of Cytochrome c on ZnO Nanoparticles Modified Carbon Paste Electrode
Authors: Negahdary Masoud , Rezaei-Zarchi Saeed , Rousta Neda , Samei Pour Soheila
Published: March 2012

The direct electrochemistry of cytochrome c (cyt c) immobilized on a modified carbon paste electrode (CPE) was described. The electrode was modified with ZnO nanoparticles. Direct electrochemistry of cytochrome c in this paste electrode was easily achieved, and a pair of well-defined quasireversible redox peaks of a heme Fe (III)/Fe(II) couple appeared with a formal potential (E0) of −0.303 V (versus SCE) in pH 7.0 phosphate buffer solution (PBS). The fabricated modified bioelectrode showed good electrocatalytic ability for reduction of H2O2. The preparation process of the proposed biosensor was convenient, and the resulting biosensor showed high sensitivity, low detection limit, and good stability.
Head and Neck Melanoma
Authors: Shashanka R. , Smitha B. R.
Published: March 2012

The incidence of malignant melanoma appears to be increasing at an alarming rate throughout the world over the past 30–40 years and continues to increase in the United States, Canada, Australia, Asia, and Europe. The behavior of head and neck melanoma is aggressive, and it has an overall poorer prognosis than that of other skin sites. The authors review the published literature and text books, intending to give an overall picture of malignant melanomas of the head and neck and a special emphasis on treatment considerations with controversies in treatment including biopsy, radiation therapy, sentinel node biopsy, and nodal dissection.
An Effective Slow-Motion Detection Approach for Compressed Soccer Videos
Authors: Kiani Vahid , Pourreza Hamid Reza
Published: March 2012

Slow-motion replays are content full segments of broadcast soccer videos. In this paper, we propose an efficient method for detection of slow-motion shots produced by high-speed cameras in soccer broadcasts. A rich set of color, motion, and cinematic features are extracted from compressed video by partial decoding of the MPEG-1 bitstream. Then, slow-motion shots are modeled by SVM classifiers for each shot class. A set of six full-match soccer games is used for training and evaluation of the proposed method. Our algorithm presents satisfactory results along with high speed for slow-motion detection in soccer videos.
Influence of personality traits on parasocial relationship with sports celebrities: A hierarchical approach
Authors: Sun Tao , Wu Guohua
Published: March 2012

Using the 3M Model of Motivation and Personality as a theoretical framework, this study develops a three‐level hierarchy of personality traits predictive of fans' parasocial relationship with sports celebrities. Specifically, the findings show that parasocial relationship with sports celebrities is determined positively by materialism (the elemental trait), negatively by self‐esteem (the compound trait) and positively by interest in sports spectatorship (the situational trait). Practical and academic implications are provided.

Copyright © 2012 John Wiley & Sons, Ltd.
A new measure of social classes
Authors: Rossiter John R.
Published: March 2012

Social classes' ‘way we live’ values remain a major influence on consumers' retail store choices, their brand choices for major durables, and their use of health services and pharmaceutical products. Social class, however, has been neglected in modern theories and research in consumer behavior, probably because of the difficulty of implementing a proper sociological measure of social class distinctions coupled with the realization that convenient sociodemographic measures of social class are not a valid substitute for the sociological measure. A new 34‐item values‐based measure of social class is presented in this article, called the Social Class Values Index (SCVI). The SCVI efficiently distinguishes the six traditional social‐class strata that are based on attributed social prestige and contributes to the first known measure of the non–prestige‐based, largely self‐actualized ‘X’ class. The SCVI is interviewer‐administered and is easily profile‐scored from simple binary answers.

Copyright © 2012 John Wiley & Sons, Ltd.
Mixing emotions: The use of humor in fear advertising
Authors: Mukherjee Ashesh , Dubé Laurette
Published: March 2012

Fear is used to advertise many products, services, and causes such as antismoking, sunscreen usage, and safe driving. Past research indicates that high levels of fear tension arousal can prompt defensive responses in the audience, which, in turn, can reduce the persuasive effect of the ad. We show in two studies that humor can reduce these defensive responses and hence increase the persuasiveness of fear advertising. Specifically, we show that increasing the level of fear tension arousal decreases persuasion when humor is absent but increases persuasion when humor is present. Further, this interaction of humor and fear tension arousal is mediated by defensive responses related to message elaboration and vulnerability to threat. Our results suggest that the effectiveness of fear advertising can be increased by adding an element of humor to the ad.

Copyright © 2012 John Wiley & Sons, Ltd.
Acute effects of single‐dose aripiprazole and haloperidol on resting cerebral blood flow (rCBF) in the human brain
Authors: Handley Rowena , Zelaya Fernando O. , Reinders A.A.T. Simone , Marques Tiago Reis , Mehta Mitul A. , O'Gorman Ruth , Alsop David C. , Taylor Heather , Johnston Atholl , Williams Steve , McGuire Philip , Pariante Carmine M. , Kapur Shitij , Dazzan Paola
Published: March 2012

Antipsychotic drugs act on the dopaminergic system (first‐generation antipsychotics, FGA), but some also directly affect serotonergic function (second‐generation antipsychotics, SGA) in the brain. Short and long‐term effects of these drugs on brain physiology remain poorly understood. Moreover, it remains unclear whether any physiological effect in the brain may be different for FGAs and SGAs. Immediate (+3.30 h) and different effects of single‐dose FGA (haloperidol, 3 mg) and a SGA (aripiprazole, 10 mg) on resting cerebral blood flow (rCBF) were explored in the same 20 healthy volunteers using a pulsed continuous arterial spin labeling (pCASL) sequence (1.5T) in a placebo‐controlled, repeated measures design. Both antipsychotics increased striatal rCBF but the effect was greater after haloperidol. Both decreased frontal rCBF, and opposite effects of the drugs were observed in the temporal cortex (haloperidol decreased, aripiprazole increased rCBF) and in the posterior cingulate (haloperidol increased, aripiprazole decreased rCBF). Further increases were evident in the insula, hippocampus, and anterior cingulate after both antipsychotics, in the motor cortex following haloperidol and in the occipital lobe the claustrum and the cerebellum after aripiprazole. Further decreases were observed in the parietal and occipital cortices after aripiprazole. This study suggests that early and different rCBF changes are evident following a single‐dose of FGA and SGA. The effects occur in healthy volunteers, thus may be independent from any underlying pathology, and in the same regions identified as structurally and functionally altered in schizophrenia, suggesting a possible relationship between antipsychotic‐induced rCBF changes and brain alterations in schizophrenia. Hum Brain Mapp, 2013. © 2012 Wiley Periodicals, Inc.
Cloud point and solvent extraction study of uranium(VI) by 8‐hydroxyquinoline
Authors: Favre‐Réguillon Alain , Murat Denis , Cote Gérard , Draye Micheline
Published: March 2012

BACKGROUND: Cloud point extraction (CPE) is an attractive alternative to solvent extraction. However, comparisons between both techniques are lacking. In this paper, the extraction of uranium(VI) using 8‐hydroxyquinoline (HQ) as chelating agent was studied by CPE using Triton X‐114 as non‐ionic surfactant and by solvent extraction using CHCl3 as diluent.

RESULTS: Using CPE, a quantitative extraction was observed for pH higher than 4.5 with a HQ/U ratio of 10. Using solvent extraction an increase in the HQ/U ratio up to 50 is necessary to obtain a near quantitative extraction. Both extraction systems were then compared with respect to the nature of extracted species, and the extraction constants determined using log‐log analysis of the extraction data. In the solvent extraction system, the extracted species were identified as UO2Q2 and the corresponding extraction constant was found to be log kex = − 3.6 ± 0.2 on the molar scale. Considering that UO2Q2 is also the extracted species in CPE, a slightly higher extraction constant, i.e. log kex = − 2.5 ± 0.3, was found.

CONCLUSION: Such a small difference in favour of the CPE system may arise from the combination of various phenomena, including effects of temperature and effects of ‘extractant environment’. However, a change in the nature of the extracted species, namely from UO2Q2 in the solvent extraction system to the formation of adducts, i.e. UO2Q2(HQ) and UO2Q2(HQ)2 in the CPE system, due to higher HQ concentration in the surfactant‐rich phase compared with chloroform, cannot be precluded, but requires confirmation. Copyright © 2012 Society of Chemical Industry
Shifts of microbial community structure during anaerobic digestion of agro‐industrial energetic crops and food industry byproducts
Authors: Merlino Giuseppe , Rizzi Aurora , Villa Federica , Sorlini Claudia , Brambilla Massimo , Navarotto Pierluigi , Bertazzoni Barbara , Zagni Matteo , Araldi Fabio , Daffonchio Daniele
Published: March 2012

BACKGROUND: Much research has been done on biochemical methane potential (BMP) determinations. However, although anaerobic digestion for methane production is driven by microorganisms, little information is available on the microbial community response to different organic residues. The aim of this study was to characterize the microbial communities during the treatment of different organic matrices.

RESULTS: BMP were comparable for energy crops and several agro‐industrial biomasses. Denaturing gradient gel electrophoresis (DGGE) showed the dominance of clostridia and Methanosarcina. Principal component analyses of PCR‐DGGE profiles indicated microbial shifts between the start and end of the processes. Microbial communities showed similar structures that, in particular for Archaea, clustered together independently of the nature of the matrix treated. Bacterial communities were richer, more dynamic and even than archaeal ones. Real‐time quantitative PCR revealed that the Methanosarcinales dominated the archaeal community while sulphate‐reducing bacteria were present at low titers. A statistically significant correlation indicated that more even archaeal communities were associated with higher BMP.

CONCLUSION: Different shifts occurred between Archaea and Bacteria exposed to different matrices treated by anaerobic digestion. While bacterial communities varied relatively widely, convergent archaeal community structures were selected in response to different biomasses treated. Copyright © 2012 Society of Chemical Industry
Reactive blending of poly(butylene succinate) and poly(triethylene succinate): characterization of the copolymers obtained
Authors: Soccio Michelina , Lotti Nadia , Gigli Matteo , Finelli Lara , Gazzano Massimo , Munari Andrea
Published: March 2012

Poly[butylene‐co‐(triethylene succinate)] block copolymers (PBSPTES), prepared by reactive blending of the parent homopolymers (PBS and PTES) in the presence of Ti(OBu)4, were analysed by nuclear magnetic resonance (NMR), wide angle X‐ray diffraction, thermogravimetric analysis and differential scanning calorimetry techniques, in order to investigate the effects of the transesterification reactions on the molecular structure and thermal properties. 1H‐NMR analysis evidenced the formation of copolymers whose degree of randomness increased with mixing time. After melt quenching, all the copolymers were found to be semicrystalline with the exception of a random copolymer. The results obtained indicated that the block size has a fundamental role in determining the rate of crystallization and therefore the phase behavior of the block copolymers. Copyright © 2012 Society of Chemical Industry
Lung function in young adults with congenital diaphragmatic hernia; a longitudinal evaluation
Authors: Spoel Marjolein , van der Cammen‐van Zijp Monique H.M. , Hop Wim C.J. , Tibboel Dick , de Jongste Johan C. , IJsselstijn Hanneke
Published: March 2012

Background

Survival rates of patients with congenital diaphragmatic hernia (CDH) have improved to up to 80%. Little is known about long‐term consequences of the disease and its treatment. We evaluated lung function and respiratory symptoms longitudinally in a previously studied cohort of CDH patients and age‐matched non‐CDH patients who underwent similar neonatal intensive care treatment.

Study Design

We tested 27 young adults [mean (SD) age: 26.8 years (2.9)] with CDH and 30 non‐CDH patients. Dynamic and static lung volumes, midexpiratory flows, and diffusion capacity were expressed as mean (SD) standard deviation scores. Prevalence of respiratory symptoms was evaluated with the European Community Respiratory Health Survey.

Results

All data are expressed as mean (SD). FEF25–75 in CDH patients had slightly deteriorated since childhood (CDH: −0.7 (1.4) vs. −1.6 (1.5), P < 0.001; non‐CDH patients: 0.2 (1.4) vs. −0.3 (1.6), P = 0.038, ns). Diffusion capacity decreased in both groups (CDH: DLCOc 0.2 (1.1) vs. −1.5 (1.1), P <0.001; non‐CDH: DLCOc 0.1 (0.4) vs. −1.1 (1.1), P < 0.001). Lung volumes were normal in both groups. The prevalence of asthma was higher than in the normal population (27.6% in patients and 30% in controls, P < 0.001).

Conclusions

Airflow obstruction and diffusion capacity deteriorated mildly from childhood into adulthood in survivors of CDH. The improved survival of patients with more severe forms of diaphragmatic hernia calls for long‐term follow‐up of lung function. Pediatr Pulmonol. 2013; 48:130–137. © 2012 Wiley Periodicals, Inc.
Enhancing mental models, analogical transfer, and performance in strategic decision making
Authors: Gary Michael Shayne , Wood Robert E. , Pillinger Tracey
Published: March 2012

Recent research suggests that managers often make strategic decisions in novel situations by utilizing past experiences to reason by analogy. However, there is substantial evidence that decision makers often fail to identify and apply knowledge about one situation to a similarly structured situation. Two experimental studies investigated the mechanisms impacting knowledge transfer from one managerial situation (the source) to an analogous situation. The results show that exposure to variation in the source situation improves transfer performance. Variation decreases performance in the short term but improves learning and increases analogical transfer. Higher performance on and systematic search of the source situation also increase transfer performance. These results yield important implications for enhancing analogical transfer in strategic decision making and for future research on reasoning by analogy. Copyright © 2012 John Wiley & Sons, Ltd.
Does it pay to be really good? addressing the shape of the relationship between social and financial performance
Authors: Barnett Michael L. , Salomon Robert M.
Published: March 2012

Building on the theoretical argument that a firm's ability to profit from social responsibility depends upon its stakeholder influence capacity (SIC), we bring together contrasting literatures on the relationship between corporate social performance (CSP) and corporate financial performance (CFP) to hypothesize that the CSP‐CFP relationship is U‐shaped. Our results support this hypothesis. We find that firms with low CSP have higher CFP than firms with moderate CSP, but firms with high CSP have the highest CFP. This supports the theoretical argument that SIC underlies the ability to transform social responsibility into profit. Copyright © 2012 John Wiley & Sons, Ltd.
Student services and auxiliary enterprises
Authors: Pittman Jeffrey S.
Published: March 2012

A greater number of campuses have broadened concepts related to student development connecting traditional student affairs and campus auxiliary services. This connection is increasingly evident in the evolution of sustainability concerns and activities.
Sustainability in housing and dining operations
Authors: Pursehouse Clive
Published: March 2012

Residential life, housing, and dining operations have the potential to touch all students by integrating sustainability issues into all operations.
Sustainability in the union
Authors: Brown Patrick , Taylor John
Published: March 2012

Operating as the center of student life, college unions have a central role to teach citizenship, social responsibility, and leadership. The perspective of stewardship is adopted in this chapter to advance a discussion about college unions as a model for campus sustainability.
Sustainability and first‐year programs
Authors: Messineo Melinda
Published: March 2012

To truly impact sustainability practices, campuses need to influence the overall campus culture including that which is fostered through first‐year programs.
Organizing for sustainability
Authors: Brown William M. , Hamburger Michael W.
Published: March 2012

A successful campus sustainability effort catalyzes broad engagement of the campus community and integration of sustainability principles into the academic and operational components of campus life.
EUV SpectroPhotometer (ESP) in Extreme Ultraviolet Variability Experiment (EVE): Algorithms and Calibrations
Authors: Didkovsky L. , Judge D. , Wieman S. , Woods T. , Jones A.
Published: March 2012

The Extreme ultraviolet SpectroPhotometer (ESP) is one of five channels of the Extreme ultraviolet Variability Experiment (EVE) onboard the NASA Solar Dynamics Observatory (SDO). The ESP channel design is based on a highly stable diffraction transmission grating and is an advanced version of the Solar Extreme ultraviolet Monitor (SEM), which has been successfully observing solar irradiance onboard the Solar and Heliospheric Observatory (SOHO) since December 1995. ESP is designed to measure solar Extreme UltraViolet (EUV) irradiance in four first-order bands of the diffraction grating centered around 19 nm, 25 nm, 30 nm, and 36 nm, and in a soft X-ray band from 0.1 to 7.0 nm in the zeroth-order of the grating. Each band’s detector system converts the photo-current into a count rate (frequency). The count rates are integrated over 0.25-second increments and transmitted to the EVE Science and Operations Center for data processing. An algorithm for converting the measured count rates into solar irradiance and the ESP calibration parameters are described. The ESP pre-flight calibration was performed at the Synchrotron Ultraviolet Radiation Facility of the National Institute of Standards and Technology. Calibration parameters were used to calculate absolute solar irradiance from the sounding-rocket flight measurements on 14 April 2008. These irradiances for the ESP bands closely match the irradiance determined for two other EUV channels flown simultaneously: EVE’s Multiple EUV Grating Spectrograph (MEGS) and SOHO’s Charge, Element and Isotope Analysis System/Solar EUV Monitor (CELIAS/SEM).
Description of two new species of the genus Thaparocleidus Jain, 1952 (Monogenea, Dactylogyridae) from freshwater fish in India: morphological and molecular phylogenetic evidence
Authors: Chaudhary A. , Singh H.S.
Published: March 2012

The present paper describes the taxonomy of two new monogeneans, namely, Thaparocleidus longiphallus sp. n. and T. siloniansis sp. n., based on morphological, morphometric and molecular biological analysis, collected from the fish Wallago attu (Bloch & Schn.) and Silonia silondia (Ham.), respectively, at Meerut, UP, India. Genetic characterization of the two new species is based on sequence analyses of the rDNA 28S gene using neighbour-joining and maximum-parsimony techniques. These methods are congruent in depicting T. longiphallus sp. n. and T. siloniansis sp. n. as closely related species, but distinct from each other and forming a subclade with other species of the genus Thaparocleidus Jain, 1952. Secondary-structure models of the large subunit rDNA of the two species were also predicted using a combined comparative and thermodynamic approach. Molecular morphometric and phylogenetic relationships of the isolates of the Thaparocleidus species are discussed in detail.
In vitro anthelmintic activity of crude extracts of selected medicinal plants against Haemonchus contortus from sheep
Authors: Ahmed M. , Laing M.D. , Nsahlai I.V.
Published: March 2012

Ethanol extracts of 25 plant species were screened for anthelmintic effects against Haemonchus contortus. Ethanol extracts of each plant were used at various concentrations (10, 20 and 30%) to treat 10-day faecal cultures, incubated at 27°C with control cultures which were treated with ethanol for 48 h. Five plants with high efficacies (Ananas comosus, Aloe ferox, Allium sativum, Lespedeza cuneata and Warburgia salutaris) were selected from the first screening for further investigation using ethanol, dichloromethane and water extracts at four concentrations (2.5, 5, 10 and 20%). Ethanol was the most effective solvent. Larval counts decreased with increasing extract concentrations, of which 10 and 20% had similar effects. Lespedeza cuneata caused more than 70% mortality at all concentrations. However, there remains a need to assess in vivo efficacy of these plants.
Impact of wave exposure on seasonal morphological and reproductive responses of the intertidal limpetFissurella crassa(Mollusca: Archaegastropoda)
Authors: Pulgar José , Alvarez Marcos , Delgadillo Alejandro , Herrera Ines , Benitez Samanta , Morales Juan Pablo , Molina Pilar , Aldana Marcela , Pulgar Victor Manuel
Published: March 2012

Intertidal organisms have long been considered an ideal system to quantify how physical variations determine differential energy allocations in specimens inhabiting environmental gradients such as exposure to wave action. In habitats with differential intertidal wave exposure (sheltered, Sh; and exposed, E) seasonal gonadal and foot weight variations and their associations with exposure and food availability (algae abundance) were determined in the keyhole limpetFissurella crassa. Gonadal weight is used as a measure of reproduction allocation whereas foot weight is an indirect indicator of energy allocation to survival. RNA:DNA ratio in limpets obtained from Sh and E habitats during the two different seasons was used as an indicator of biosynthetic capability. Our results indicate that algae abundance in E sites was higher in summer and lower in winter compared to Sh sites. In E sites the muscular foot weight of limpet was higher in summer in contrast to Sh sites whereF. crassamuscular foot weight of limpet was higher in winter. Gonadal weight in Sh sites was higher in summer and remained constant in winter; whereas in E sites gonadal weight was lower in summer and higher in winter. RNA:DNA ratios indicate that regardless of intertidal wave exposure,F. crassashowed higher biosynthetic capability in summer. Energetic allocation in animals that inhabit sheltered intertidal habitats would support constant allocation towards reproduction. In contrast, animals that inhabit exposed habitats may favour seasonally reproduction allocation at expense of survival.
Seasonal variation in breeding Rüppell’s Vultures Gyps rueppellii at Kwenia, southern Kenya and implications for conservation
Authors: VIRANI MUNIR Z. , MONADJEM ARA , THOMSETT SIMON , KENDALL CORINNE
Published: March 2012

Vulture populations have been declining globally and regionally within Africa. Rüppell’s Vulture Gyps rueppellii is currently listed as ‘Near Threatened’ and numbers of the species, along with African White-backed Vultures G. africanus, have declined by 52% in and around the Mara-Serengeti ecosystem. A large breeding colony of Rüppell’s Vulture at Kwenia, southern Kenya, was monitored between 2002 and 2009. Around 150–200 adults were present on each visit, with up to 64 simultaneously active nests. The date of egg-laying differed considerably between years, with two discrete breeding attempts in some years. Nests were not positioned randomly across the cliff face and the number of active nests was related to rainfall in the previous year. The large ungulate migration of the Mara-Serengeti provides a vital foraging ground for the species. Conservation implications of the loss of vultures are discussed.
HAS GLOBALIZATION TRANSFORMED U.S. MACROECONOMIC DYNAMICS?
Authors: Milani Fabio
Published: March 2012

This paper estimates a structural New Keynesian model to test whether globalization has changed the behavior of U.S. macroeconomic variables. Several key coefficients in the model–such as the slopes of the Phillips and IS curves, the sensitivities of domestic inflation and output to “global” output, and so forth–are allowed in the estimation to depend on the extent of globalization (modeled as the changing degree of openness to trade of the economy), and, therefore, they become time-varying. The empirical results indicate that globalization can explain only a small part of the reduction in the slope of the Phillips curve. The sensitivity of U.S. inflation to global measures of output may have increased over the sample, but it remains very small. The changes in the IS curve caused by globalization are similarly modest. Globalization does not seem to have led to an attenuation in the effects of monetary policy shocks. The nested closed-economy specification still appears to provide a substantially better fit of U.S. data than various open-economy specifications with time-varying degrees of openness. Some time variation in the model coefficients over the postwar sample exists, particularly in the volatilities of the shocks, but it is unlikely to be related to globalization.
Influence of Pb(II) Concentration and pH of Acetate Buffer on the Potential Window of a Lead Film Electrode: An Atomic Force Microscopy Study
Authors: Tyszczuk-Rotko Katarzyna
Published: March 2012

Atomic force microscopy (AFM) studies on observations of lead films deposited from the solutions containing an acetate buffer and different concentration of Pb(II) are presented. AFM images show considerable variability in morphology of the deposited lead layer depending on experimental conditions. To investigate effects of the Pb(II) concentration and pH of the supporting electrolyte on the accessible potential window of the lead film electrode (PbFE), voltammetric techniques were used. It was found that the useful potential window of PbFE is affected by the pH and Pb(II) concentration. Additionally, it was found that the distribution and large size of Pb particles on the electrode surface shown by AFM corresponded well to the mass of Pb expected on the glassy carbon support with respect to the voltammetric data. Results reveal that PbFE is an attractive nonmercury metallic electrode suitable for electrochemical detection of metal ions and a lot of organic compounds in a wide potential window. The accessible potential window of the PbFE in an acetate buffer (pH = 5.0) was compared to those obtained at the bismuth film electrode and antimony film electrode.
Melting and channelized magmatic flow in chemically heterogeneous, upwelling mantle
Authors: Weatherley S. M. , Katz R. F.
Published: March 2012

Beneath mid‐ocean ridges, magma is thought to rise through a network of high porosity channels that form by reactive flow. Partial mantle melts travel rapidly through these channels to the surface, and retain the geochemical signature of their source rock. Global analyses of mid‐ocean ridge lavas indicates that the mantle is chemically heterogeneous, but the consequences of this heterogeneity for reactive porous flow remain unclear. Using numerical models of coupled magma/mantle dynamics, we investigate the relationships between mantle heterogeneity, melting, and magmatic channelization. The models are based on conservation mass, momentum, energy, and composition in a system with two phases and two thermodynamic components in local thermodynamic equilibrium. One of these components is more fusible than the other. In this context, we find that heterogeneities enriched in the more fusible component can nucleate magmatic channels. To understand this result we consider an expression for the melting rate derived from the conservation principles. This expression quantifies the relationship of decompression, reactive flow, and thermal diffusion to the melting rate. With it, we assess their relative importance in the ambient mantle, channels, and enriched heterogeneities. In our models, heat diffuses into fertile channels and powers melting, in combination with reactive flow. These results suggest that thermal diffusion influences the dynamics of magmatic channelization.
Tracking lava flow emplacement on the east rift zone of Kīlauea, Hawai‘i, with synthetic aperture radar coherence
Authors: Dietterich Hannah R. , Poland Michael P. , Schmidt David A. , Cashman Katharine V. , Sherrod David R. , Espinosa Arkin Tapia
Published: March 2012

Lava flow mapping is both an essential component of volcano monitoring and a valuable tool for investigating lava flow behavior. Although maps are traditionally created through field surveys, remote sensing allows an extraordinary view of active lava flows while avoiding the difficulties of mapping on location. Synthetic aperture radar (SAR) imagery, in particular, can detect changes in a flow field by comparing two images collected at different times with SAR coherence. New lava flows radically alter the scattering properties of the surface, making the radar signal decorrelated in SAR coherence images. We describe a new technique, SAR Coherence Mapping (SCM), to map lava flows automatically from coherence images independent of look angle or satellite path. We use this approach to map lava flow emplacement during the Pu‘u ‘Ō‘ō‐Kupaianaha eruption at Kīlauea, Hawai‘i. The resulting flow maps correspond well with field mapping and better resolve the internal structure of surface flows, as well as the locations of active flow paths. However, the SCM technique is only moderately successful at mapping flows that enter vegetation, which is also often decorrelated between successive SAR images. Along with measurements of planform morphology, we are able to show that the length of time a flow stays decorrelated after initial emplacement is linearly related to the flow thickness. Finally, we use interferograms obtained after flow surfaces become correlated to show that persistent decorrelation is caused by post‐emplacement flow subsidence.
Statistical analysis of the relationships between faults attributes
Authors: Kolyukhin Dmitriy , Torabi Anita
Published: March 2012

The statistical analysis of fault attributes scaling relationships is discussed. Dependences of length, width of damage zone and thickness of fault core on displacement were studied assuming power law relations. The approximation forms a piecewise‐linear function with few slopes in log‐log scale. The Bayesian Information Criterion (BIC) was used to find the best fit for an optimal number of parameters. Numerical tests show that the best fit was obtained when using power law relations with two slopes. Bayesian analysis of model parameters' probability distribution was performed. For length‐displacement relation (L‐D), the slope decreases from one scale of faults to another. This change occurs at ∼1 m displacement for reverse and normal faults in siliciclastic rocks, at ∼1500 m displacement for strike slip and at ∼300 m displacement for normal faults in non‐siliciclastic rocks. The slope of the damage zone width‐displacement (W‐D) relation decreases at ∼10 m, while it slightly increases for fault core thickness‐displacement (T‐D) relation at ∼10 cm. The result of the probability density of changepoints confirms the calculated changepoints, which correspond to maximal BIC in most cases. We propose an evolutionary growth pattern of faults based on the statistical results, in which faults lengthen during the initial stage. During subsequent overlapping and linkage between the faults, mainly displacement accumulates. Fault damage zone and fault core form early in the process of faulting. In mature faults, the development of damage zone would be slower than for small faults, whereas fault core slightly thickens with further localization.
Total water storage dynamics in response to climate variability and extremes: Inference from long‐term terrestrial gravity measurement
Authors: Creutzfeldt Benjamin , Ferré Ty , Troch Peter , Merz Bruno , Wziontek Hartmut , Güntner Andreas
Published: March 2012

Terrestrial water storage is a basic element of the hydrological cycle and a key state variable for land surface‐atmosphere interaction. However, measuring water storage in a comprehensive way for different storage compartments and beyond the point scale is a challenge. In this study, we explore a 10‐year time series of total water storage changes derived from high‐precision superconducting gravimeter observations in a headwater catchment in Southern Germany. In combination with hydro‐meteorological data, we examine the relationship between gravity‐derived water storage changes, climate, and river discharge. Distinct seasonal water storage dynamics observed by the gravimeter are strongly related to the meteorological forcing, in particular evapotranspiration. Intra‐annual water storage variations demonstrate that the simplifying assumption of water storage averaging to zero at the annual scale is not valid for this catchment. At the event‐scale, gravimeters provide a measure of the available subsurface water storage capacity, which can be useful for runoff prediction. During the Central European drought in 2003, the gravimeter data show a strong depletion of water storage and a long‐term recovery that extended over a period of several years. In comparison to point measurements or different environmental indices, our findings suggest that depth‐integrated gravimeter measurements give a more complete picture of the dynamics of a hydrologic system in response to climate variability and extremes. In view of the considerable costs of gravimeters concerning the infrastructure and measurements, we suggest the strategic deployment of gravimeters at selected sites of hydro‐meteorological monitoring networks.
Carbonaceous species and humic like substances (HULIS) in Arctic snowpack during OASIS field campaign in Barrow
Authors: Voisin Didier , Jaffrezo Jean‐Luc , Houdier Stéphan , Barret Manuel , Cozic Julie , King Martin D. , France James L. , Reay Holly J. , Grannas Amanda , Kos Gregor , Ariya Parisa A. , Beine Harry J. , Domine Florent
Published: March 2012

Snowpacks contain many carbonaceous species that can potentially impact on snow albedo and arctic atmospheric chemistry. During the OASIS field campaign, in March and April 2009, Elemental Carbon (EC), Water insoluble Organic Carbon (WinOC) and Dissolved Organic Carbon (DOC) were investigated in various types of snow: precipitating snows, remobilized snows, wind slabs and depth hoars. EC was found to represent less than 5% of the Total Carbon Content (TCC = EC + WinOC + DOC), whereas WinOC was found to represent an unusual 28 to 42% of TCC. Snow type was used to infer physical processes influencing the evolution of different fractions of DOC. DOC is highest in soil influenced indurated depth hoar layers due to specific wind related formation mechanisms in the early season. Apart from this specific snow type, DOC is found to decrease from precipitating snow to remobilized snow to regular depth hoar. This decrease is interpreted as due to cleaving photochemistry and physical equilibration of the most volatile fraction of DOC. Depending on the relative proportions of diamond dust and fresh snow in the deposition of the seasonal snowpack, we estimate that 31 to 76% of DOC deposited to the snowpack is reemitted back to the boundary layer. Under the assumption that this reemission is purely photochemical, we estimate an average flux of VOC out of the snowpack of 20 to 170 μgC m−2 h−1. Humic like substances (HULIS), short chain diacids and aldehydes are quantified, and showed to represent altogether a modest (<20%) proportion of DOC, and less than 10% of DOC + WinOC. HULIS optical properties are measured and could be consistent with aged biomass burning or a possible marine source.
Estimating sediment transport in rivers using seismic detections
Authors: Schultz Colin
Published: March 2012

Rocks and sand carried in a river's flows, which bump, grind, and scrape against the riverbed, are an important force in driving topographic change by controlling riverbed erosion and incision rates over long time scales. Sediment transport observations collected worldwide have typically been sparse, infrequent, or inconsistent, even within some of the world's most important rivers. In mountainous rivers, where sediment‐driven erosion is an even more important force than in low‐lying watersheds, even basic measurements are often nonexistent. Tsai et al. seek to alleviate this sparsity of data by introducing a method to use seismic wave detections to estimate basic sediment transport information. The authors' model uses data on the high‐frequency, low‐amplitude seismic waves that are produced every time a rock or pebble settles out of the river's flows and hits the riverbed. When combined with measurements of the sediment grain size distribution collected in the field, the seismic signals allowed the authors to estimate the number of grains of each size, the total sediment mass, and the velocity of the rock‐riverbed collision.
Low‐energy ions dominate the space environments of Earth, Mars, and Venus
Authors: Schultz Colin
Published: March 2012

Stretching from the top of the ionosphere to out into space, the terrestrial space environment is packed with low‐energy ions, populated when ultraviolet radiation emanating from the Sun ionizes atmospheric gases in the ionosphere below. These ions, with energies of a few electron volts, play an important role in modifying dynamics within the magnetosphere. Though this view of the space environment is well grounded in theory, the actual detection and quantification of low‐energy ion densities have been more elusive. The difficulty stems from the environmental conditions within which sensors seeking to measure these low‐energy ions must operate. Satellites high above the Earth accumulate surface charges giving positive potentials of tens to hundreds of volts when exposed to sunlight and end up repelling the low‐velocity, low‐energy, positively charged ions that researchers hoped to detect. Using an array of techniques, including a recently developed approach whereby onboard sensors look for distortions in the electric field in the satellite's own wake, André and Cully estimate the density of low‐energy ions.
Quantifying volcanic ash dispersal and impact of the Campanian Ignimbrite super‐eruption
Authors: Costa A. , Folch A. , Macedonio G. , Giaccio B. , Isaia R. , Smith V. C.
Published: March 2012

We apply a novel computational approach to assess, for the first time, volcanic ash dispersal during the Campanian Ignimbrite (Italy) super‐eruption providing insights into eruption dynamics and the impact of this gigantic event. The method uses a 3D time‐dependent computational ash dispersion model, a set of wind fields, and more than 100 thickness measurements of the CI tephra deposit. Results reveal that the CI eruption dispersed 250–300 km3 of ash over ∼3.7 million km2. The injection of such a large quantity of ash (and volatiles) into the atmosphere would have caused a volcanic winter during the Heinrich Event 4, the coldest and driest climatic episode of the Last Glacial period. Fluorine‐bearing leachate from the volcanic ash and acid rain would have further affected food sources and severely impacted Late Middle‐Early Upper Paleolithic groups in Southern and Eastern Europe.
The dependence of the coupled magnetosphere‐ionosphere‐thermosphere system on the Earth's magnetic dipole moment
Authors: Cnossen Ingrid , Richmond Arthur D. , Wiltberger Michael
Published: March 2012

The strength of the Earth's magnetic field changes over time. We use simulations with the Coupled Magnetosphere‐Ionosphere‐Thermosphere model to investigate how the magnetosphere, upper atmosphere, and solar quiet (Sq) geomagnetic variation respond as the geomagnetic dipole moment M varies between 2⋅1022 and 10⋅1022 Am2. We find that the magnetopause stand‐off distance and the cross‐polar cap potential increase, while the polar cap size decreases, with increasing M. Their dependence on M is stronger than predicted by previous studies. We also show for the first time that the shape of the magnetosphere starts to change for M ≤ 4⋅1022 Am2. This may be due to enhanced magnetopause erosion and/or to strong changes in the ionospheric conductance, which affect the field‐aligned currents and the magnetic fields they create in the magnetosphere, thus modifying the magnetic pressure inside the magnetosphere. E × B drift velocities, Joule heating power, the global mean thermospheric temperature and the global mean height of the peak of the ionospheric F2 layer, hmF2, all increase with increasing M for low dipole moments, but all decrease with increasing M for larger dipole moments. The peak electron density of the F2 layer, NmF2, shows the opposite behavior. The Sq amplitude decreases with increasing M and this dependence can be roughly described by a power law scaling. Most scaling relations show a weak dependence on the solar activity level, which is likely associated with a change in the relative contributions to the Pedersen conductance from the upper and lower ionosphere, which scale differently with M.
A new outlook towards kidney injuries
Authors: Satwekar Mahesh , Satwekar Abhijeet
Published: March 2012

Acute and chronic progression of injury to the kidney leads to the failure of the renal system and has become an increasingly important cause of morbidity and mortality. Present diagnosis detects the condition only after irreversible loss of 70 percent of kidney function. Current research is focused only on the clinical manifestations after the kidney injuries and not towards the exact cause of the condition. Here we propose a new outlook- that there is an involvement of a pathogen in the pathogenesis of kidney injuries. Basis for our proposal is given by the similarity of the pathogenesis events occurring between a classical example of hepatitis and kidney injuries. Furthermore, literature regarding the role of early kidney injury biomarkers in innate immunity indicates the involvement of the pathogen. Research in this theme possesses a strong possibility in the development of therapeutic, preventive and management strategies for the acute and chronic kidney injuries.