bluuebunny/crossref_metadata_2025 huggingface dataset:
A Multinational Study of the Diffusion of a Discontinuous Innovation
Authors: Atkin Thomas , Garcia Rosanna , Lockshin Lawrence
Published: June 2010

There has been a great deal written about the diffusion of discontinuous technical innovations, but very little about diffusion of discontinuous innovations in other areas, such as packaging. Also, little research explores differences in diffusion rates of low-technological discontinuous innovations in different countries or cultures. This project studies the differences in the diffusion process for the screw cap on wine bottles in three countries. We use an internet survey of over 3,600 wine consumers to understand why this discontinuous innovation appears to be slower to diffuse in one country (the US), than in the other two (Australia and New Zealand). Logistic regression is used to model the characteristics of adopters versus non-adopters in each country. Our results show that educating the consumer about the advantages of discontinuous innovations can help to speed diffusion. Education can occur through advertising programs directed at the media and consumers, and also through word-of-mouth campaigns directed at consumers.
Evidence concerning the Importance of Perceived Brand Differentiation
Authors: Romaniuk Jenni , Sharp Byron , Ehrenberg Andrew
Published: June 2010

The credibility and vibrancy of any discipline depends on a willingness to question even the most strongly held beliefs. Our research challenges the central importance of differentiation to brand strategy. We provide an empirically grounded theoretical argument that differentiation plays a more limited role in brand competition than the orthodox literature assumes. We then present empirical data, spanning many categories and two countries, showing that there is a low level of perceived differentiation across competing brands. However, despite this lack of perceived differentiation, customers are still buying these brands. This leads us to question the importance of perceived and valued differentiation and to instead place distinctiveness at the centre of brand strategy - where a brand builds unique associations that simply make it more easily identifiable. We discuss the very positive implications for marketing management and call for research on being distinctive and getting noticed.
Investigating the Idiosyncratic Nature of Brand Value
Authors: Miller Karen W.
Published: June 2010

This study investigated the idiosyncratic nature of brand value by examining customer brand assessments of how well a brand matches the self-concept, how significant a brand is in a customer's life, favourable attitudes toward a brand, their relationships and their influence on overall brand value. Drawing from a sample of 210 generation Y (18-25 year old) wearers of athletic footwear in Australia it was found that brand fit indirectly influences overall brand value through brand significance and brand attitudes. The influence of brand significance on brand value was found to be stronger for the market leader than that of the market follower.
Service Quality: Insights from the Indian Banking Scenario
Authors: Choudhury Koushiki
Published: June 2010

The Indian banking industry is going through turbulent times. With the lowering of entry barriers and blurring of product lines of banks and non-banks since the financial sector reforms, banks are functioning increasingly under competitive pressures. Hence, it is imperative that banks maintain a loyal customer base. In order to achieve this and improve their market and profit positions, many retail banks are directing their strategies towards increasing customer satisfaction and loyalty through improved service quality. Moreover, with the advent of international banking, the trend towards larger bank holding companies, and innovations in the marketplace, customers have greater and greater difficulty in distinguishing and selecting one institution from another. Therefore the current problem for the banking industry in India is to determine the dimensions of customer-perceived service quality. This is because if service quality dimensions can be identified, service managers should be able to improve the delivery of customer perceived quality during the service process and have greater control over the overall outcome.

The objective of the study was to explore the dimensions of customer perceived service quality in the context of the Indian retail banking industry. A set of service quality parameters, drawn from customers’ perceptions about service quality as well as the bank marketing and service quality literature, were drawn up. These parameters have been used in the context of four of the largest banks in India to identify the underlying dimensions of service quality, using factor analysis.

The study suggests that customers distinguish four dimensions of service quality in the case of the retail banking industry in India, namely, attitude, competence, tangibles and convenience. Identifying the underlying dimensions of the service quality construct in the Indian retail banking industry is the first step in the definition and hence provision of quality service. This article has drawn upon the findings of the service quality dimensions to contend the initiatives that banks’ managers can take to enhance employees’ skills and attitudes and instill a customer-service culture.
CO-REPRESENTATIONS OF HOPF–VON NEUMANN ALGEBRAS ON OPERATOR SPACES OTHER THAN COLUMN HILBERT SPACE
Authors: RUNDE VOLKER
Published: June 2010

Recently, Daws introduced a notion of co-representation of abelian Hopf–von Neumann algebras on general reflexive Banach spaces. In this note, we show that this notion cannot be extended beyond subhomogeneous Hopf–von Neumann algebras. The key is our observation that, for a von Neumann algebra 𝔐 and a reflexive operator space E, the normal spatial tensor product $\M \btensor \CB (E)$ is a Banach algebra if and only if 𝔐 is subhomogeneous or E is completely isomorphic to column Hilbert space.
HOLOMORPHIC FLOWS WITH PERIODIC ORBITS ON STEIN SURFACES
Authors: SCÁRDUA BRUNO
Published: June 2010

In this paper we study the classification of holomorphic flows on Stein spaces of dimension two. We assume that the flow has periodic orbits, not necessarily with a same period. Then we prove a linearization result for the flow, under some natural conditions on the surface.
Drumming from Screen to Stage: Ondekoza'sŌdaikoand the Reimaging of Japanese Taiko
Authors: Bender Shawn
Published: June 2010

In a performance ofŌdaiko,arguably the most iconic and widely performed piece in Japanese taiko drumming, a loincloth-clad man pounds furiously on a huge Japanese drum to the point of near exhaustion. Although this piece often is assumed to descend from Japan's rich heritage of folk drumming, this article argues instead thatŌdaikowas inspired by a fictional representation of festival drumming in the mid-century Japanese filmThe Rickshaw Man (Muhōmatsu no isshō).In addition, the revealing clothing worn in the performance derives not from Japanese custom but from the input of the French designer Pierre Cardin. Tracing the emergence ofŌdaikoin the influential taiko ensemble Ondekoza, this article sheds light on the potent mixture of folkloric instrumentation and modern sensibility that distinguishes contemporary taiko drumming.
Generation of sheared flows by drift waves in a strongly magnetized electron–positron–ion plasma
Authors: SHUKLA NITIN , SHUKLA P. K.
Published: June 2010

It is shown that sheared/zonal flows (ZFs) can be nonlinearly excited by incoherent drift waves (DWs) in a strongly magnetized non-uniform plasma composed of electrons, positrons and ions. The dynamics of incoherent DWs in the presence of ZFs is governed by a wave-kinetic equation. The governing equation for ZFs in the presence of nonlinear forces (associated with nonlinear ion polarization and nonlinear ion-diamagnetic drifts) of the DWs is deduced by combining the Poisson equation, as well as the e-p-i continuity equations, together with appropriate plasma particle velocities in the DW and the ZF fields. Standard techniques are used to derive a nonlinear dispersion relation, which depicts two classes of the modulational instability of the DWs against the ZFs. Non-thermal ZFs can reduce the turbulent cross-field particle transport in non-uniform, strongly magnetized e-p-i plasmas.
Real class sizes and real character degrees
Authors: GURALNICK ROBERT M. , NAVARRO GABRIEL , TIEP PHAM HUU
Published: June 2010

Perhaps unexpectedly, there is a rich and deep connection between field of values of characters, their degrees and the structure of a finite group. Some of the fundamental results on the degrees of characters of finite groups, as the Ito–Michler and Thompson's theorems, admit a version involving only characters with certain fixed field of values ([DNT, NS, NST2, NT1, NT3]).
Bounds on fewnomial exponential sums over ℤp
Authors: COCHRANE TODD , PINNER CHRISTOPHER
Published: June 2010

We obtain a number of new bounds for exponential sums of the type S(χ, f) = ∑x = 1p−1 χ(x) ep(f(x)), with p a prime, f(x) = ∑i = 1raixki, ai, ki ∈ ℤ, 1 ≤ i ≤ r and χ a multiplicative character (mod p). The bounds refine earlier Mordell-type estimates and are particularly effective for polynomials in which a certain number of the ki have a large gcd with p − 1. For instance, if f(x) = ∑i = 1maixki + g(xd) with d|(p − 1) then ${|S(\chi,f)| \le p\ (k_1\cdots k_m)^{\frac1{m^2}}/d^{\frac 1{2m}}$. If f(x) = axk + h(xd) with d|(p − 1) and (k, p − 1) = 1 then $|S(\chi,f)|\le p/\sqrt{d}$, and if f(x) = axk + bx−k + h(xd) with d|(p − 1) and (k, p − 1) = 1 then $|S(\chi,f)| \le p/\sqrt{d} + \sqrt{2} p^{3/4}$.
New hypotheses for the health-protective mechanisms of whole-grain cereals: what is beyond fibre?
Authors: Fardet Anthony
Published: June 2010

Epidemiological studies have clearly shown that whole-grain cereals can protect against obesity, diabetes, CVD and cancers. The specific effects of food structure (increased satiety, reduced transit time and glycaemic response), fibre (improved faecal bulking and satiety, viscosity and SCFA production, and/or reduced glycaemic response) and Mg (better glycaemic homeostasis through increased insulin secretion), together with the antioxidant and anti-carcinogenic properties of numerous bioactive compounds, especially those in the bran and germ (minerals, trace elements, vitamins, carotenoids, polyphenols and alkylresorcinols), are today well-recognised mechanisms in this protection. Recent findings, the exhaustive listing of bioactive compounds found in whole-grain wheat, their content in whole-grain, bran and germ fractions and their estimated bioavailability, have led to new hypotheses. The involvement of polyphenols in cell signalling and gene regulation, and of sulfur compounds, lignin and phytic acid should be considered in antioxidant protection. Whole-grain wheat is also a rich source of methyl donors and lipotropes (methionine, betaine, choline, inositol and folates) that may be involved in cardiovascular and/or hepatic protection, lipid metabolism and DNA methylation. Potential protective effects of bound phenolic acids within the colon, of the B-complex vitamins on the nervous system and mental health, of oligosaccharides as prebiotics, of compounds associated with skeleton health, and of other compounds such as α-linolenic acid, policosanol, melatonin, phytosterols andpara-aminobenzoic acid also deserve to be studied in more depth. Finally, benefits of nutrigenomics to study complex physiological effects of the ‘whole-grain package’, and the most promising ways for improving the nutritional quality of cereal products are discussed.
The Contributions of Otto Scherzer (1909–1982) to the Development of the Electron Microscope
Authors: Marko Michael , Rose Harald
Published: June 2010

Otto Scherzer was one of the pioneers of theoretical electron optics. He was coauthor of the first comprehensive book on electron optics and was the first to understand that round electron lenses could not be combined to correct aberrations, as is the case in light optics. He subsequently was the first to describe several alternative means to correct spherical and chromatic aberration of electron lenses. These ideas were put into practice by his laboratory and students at Darmstadt and their successors, leading to the fully corrected electron microscopes now in operation.
State responses to ‘Ethnic Riots’ in liberal democracies: evidence from Western Europe
Authors: Bleich Erik , Caeiro Carolina , Luehrman Sarah
Published: June 2010

The study of ethnic riots has a substantial pedigree in the social sciences, but so far there has been no systematic attempt to unify insights from scholars working on different areas of the world, nor has there been any extensive application of existing knowledge to the study of Western Europe. We address these two lacunae by drawing on contemporary scholarship to generate testable hypotheses about state responses to ethnic riots in liberal democracies, and by conducting a preliminary test of these hypotheses on four controlled comparison cases from Britain and France. Our cases reveal that states employ a relatively even balance of repression and accommodation in keeping with thesocial controlperspective, but that the precise balance is affected by theelectoral incentivesof the party in power. This evidence suggests the external validity of findings by Fording (2001) – who emphasizes the significance of social control in the American context – and Wilkinson (2004) – who stresses the importance of electoral incentives in the Indian environment – but it implies that these separate insights may be more powerful in combination. Our study also demonstrates the limitations of perspectives that predict either simple repression or accommodation of rioters, and of those that emphasize distinctive national responses to riots.
The normative origins of democracy in the European Union: toward a transformationalist theory of democratization
Authors: Schimmelfennig Frank
Published: June 2010

Institutional democratization has made considerable progress in the history of the European Union (EU). Mainstream theories of democratization, however, fail to capture this process because they are wedded to the nation-state context. This paper therefore proposes a transformationalist theory of democratization beyond the state. EU democratization results from the conflict about the redistribution of political competences between institutional actors in a multilevel system, in which liberal democracy is the shared norm of legitimate authority. To the extent that institutional actors, who push for further integration in order to increase efficiency, undermine existing democratic institutions at the national level, their competitors can put into question the legitimacy of integration by invoking the shared liberal democratic community norms and shame them into making democratic concessions. The normative origins of democracy in the EU are illustrated in case studies on democratic membership conditionality, legislative rights of the European Parliament, and the institutionalization of human rights in the EU.
Non-hierarchical policy coordination in multilevel systems
Authors: Bolleyer Nicole , Börzel Tanja A.
Published: June 2010

In theory, lower-level governments (provinces, regional governments, or member states) operating in multilevel systems within and beyond the nation-state can choose from a wide repertoire of modes of policy coordination to solve collective problems non-hierarchically. These modes range from unilateral policy emulation over informal intergovernmental agreements to binding interstate law. The modes that governments arewillingandcapable to use, however, vary considerably across multilevel systems which affects governments’ collective problem-solving capacity. This paper argues that the nature of executive–legislative relations in lower-level governments is crucial to account for this variation. The presence (or absence) of power sharing shapes thewillingnessof lower-level governments to enter agreements that greatly constrain individual government autonomy. Power-concentrating governments, as opposed to power-sharing ones, tend to avoid such agreements. Thetypeof power sharing affects thecapacityto enter agreements that require legislative approval. Compulsory power-sharing governments, as opposed to voluntary power-sharing governments, should find it difficult to enter such agreements, since this type of power sharing invites inter-branch divides. To substantiate these arguments, we apply them to Canada, Switzerland, the United States, and the European Union.
Rationality and risk-taking in Russia’s first Chechen War: toward a theory of cognitive realism
Authors: Morrissette Jason J.
Published: June 2010

This article seeks to establish a better scholarly understanding of former Russian President Boris Yeltsin’s decision to launch an ill-planned, risky, and ultimately disastrous invasion of the breakaway republic of Chechnya in 1994. Examining the decision-making environment that led up to the invasion, I conclude that while neorealism provides an adequate explanation for Yeltsin’s motives in this case, the decisions that he made in pursuit of these goals do not reflect the logic of rational utility maximization commonly associated with neorealist theory. Instead, I suggest that prospect theory – based on the idea that decision-makers tend to be risk averse when confronted with choices between gains while risk acceptant when confronted with losses – offers significantly more explanatory insight in this case. Thus, the article offers further support for an alternative theoretical approach to international relations that some scholars have termed ‘cognitive realism’, incorporating neorealist motives with a more empirically accurate perspective on the decision-making processes undertaken in pursuit of these motives.
Thunderstorm characteristics associated with RHESSI identified terrestrial gamma ray flashes
Authors: Splitt M. E. , Lazarus S. M. , Barnes D. , Dwyer J. R. , Rassoul H. K. , Smith D. M. , Hazelton B. , Grefenstette B.
Published: June 2010

The characteristics of thunderstorms that produce terrestrial gamma‐ray flashes (TGFs) observed by the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) are determined using climatological and meteorological data. RHESSI observed TGFs follow diurnal, seasonal, and geographic patterns that are very similar to those of thunderstorms confirming, in part, that these events are directly connected to thunderstorm activity. The TGF producing thunderstorms are shown to be closely associated with tall (ranging from 13.6 km to 17.3 km) tropical thunderstorm systems, a finding that is consistent with theoretical expectations from models of relativistic breakdown that relate the source region to the spectral signatures observed by RHESSI. Unlike sprites, there appears to be no predilection for TGFs to occur with large thunderstorm complexes. Rather, TGF producing thunderstorms are shown to range in areal extent by several orders of magnitude. Analysis of a single TGF event within the Mozambique Channel indicates an elevated mixed phase (both liquid water and ice present) level of approximately 6 km which is consistent with the climatological findings.
Climatology of the stationary planetary waves seen in the SABER/TIMED temperatures (2002‐2007)
Authors: Mukhtarov P. , Pancheva D. , Andonov B.
Published: June 2010

The paper focuses on the global spatial structure, seasonal and interannual variability of the stationary planetary waves (SPW) with zonal wavenumber s = 1 (SPW1) and s = 2 (SPW2) derived from the SABER/TIMED temperature measurements for 6 full years (January 2002–December 2007). The monthly mean climatological (multiyear average, 2002–2007) depictions of SPW temperature field extending between 20 and 120 km altitude and ±50° latitude are derived. A special attention is paid to the SPW temperature field in the lower thermosphere where the SPW1 amplifies in May and December–January in the northern hemisphere (NH) and in April–May and November in the southern hemisphere (SH). Amplitudes in both hemispheres are similar in strato‐mesosphere; however, in the lower thermosphere SH amplitudes are significantly larger (∼30 K) than those in NH (∼20 K). The NH SPW1 is able to propagate up to 115 km altitude contributing to the winter amplification of the lower thermospheric SPW1, but that from the SH cannot penetrate above ∼90–100 km. In the lower thermosphere (above h = 100 km) mainly trapped SPW signal is observed. The SPW1 are almost out of phase in both hemispheres; the average (2002–2007) phases are ∼100°W in NH and ∼120°E in SH. Strong evidence indicates that auroral heating is a main origin of the lower thermospheric SPW temperature field.
Low heat flux and large variations of lithospheric thickness in the Canadian Shield
Authors: Lévy F. , Jaupart C. , Mareschal J.‐C. , Bienfait G. , Limare A.
Published: June 2010

Ten new heat flux determinations have been made using measurements in 22 mining exploration boreholes located at latitudes higher than 51°N in the Canadian Shield. They provide data in poorly sampled regions near the core of the North American craton where one expects the lithosphere to be thickest. The new heat flux values are all smaller than 34 mW m−2 and are among the lowest recorded so far in the shield. For all the new sites, there is no relationship between heat flux and heat production in surface rocks. In the Canadian Shield, heat flux variations occur at wavelengths <100 km and are mostly of crustal origin. Local averages in two 250 × 250 km windows located on Archean areas at high latitudes on either side of James Bay are 29 mW m−2 and 31 mW m−2, the lowest values found so far at this scale in the Canadian Shield. S wave traveltime delays derived from tomographic models provide the additional constraints needed to resolve differences of deep lithospheric thermal structure. There is no significant correlation between average surface heat flux and traveltime delays within the Canadian Shield, confirming that variations of the surface heat flux are mostly of crustal origin. Traveltime delays cannot be explained by variations in crustal heat production only and require variations of heat supply to the lithosphere and/or radiogenic heat production in the lithospheric mantle. These variations are associated with changes of lithospheric thickness that may be as large as 80 km. The heat flux at the base of the Superior lithosphere is constrained to be 11 ± 2 mW m−2.
The FeSi phase diagram to 150 GPa
Authors: Lord O. T. , Walter M. J. , Dobson D. P. , Armstrong L. , Clark S. M. , Kleppe A.
Published: June 2010

The melting curve of FeSi has been determined to 150 GPa in the laser‐heated diamond anvil cell (LH‐DAC) on the basis of discontinuities in the power versus temperature function. A multianvil experimental cross‐check at 12 GPa using textural criteria as a proxy for melting is in good agreement with our LH‐DAC results. The melting point of FeSi reaches ∼4000 K at the core mantle boundary and an extrapolated value of 4900 K at the inner‐core boundary (ICB). We also present the melting curve as determined by the Lindemann melting law; this agrees well with our experimental curve to 70 GPa and then diverges to higher temperatures, reaching 6200 K at the ICB. These temperatures are substantially higher than previous LH‐DAC determinations. The boundary of the ɛ‐FeSi → CsCl‐FeSi subsolidus transition has also been determined by synchrotron‐based X‐ray diffraction at high pressures, and the results confirm a negative Clapeyron slope for the transition. We conclude that if present, FeSi is likely to be solid within the D″ layer and is unlikely to be present within the inner core for any plausible bulk core silicon content.
Effect of initial conditions and loading path on earthquake nucleation
Authors: Fang Zijun , Dieterich James H. , Xu Guanshui
Published: June 2010

Previous studies of earthquake nucleation on faults with rate‐ and state‐dependent friction show that nucleation process initially consists of a characteristic phase of localization to a limiting dimension, followed in some cases by a late‐stage nucleation‐zone expansion. Processes controlling the nucleation zone dimension are of interest for understanding scaling of the minimum earthquake dimensions and scaling of premonitory processes associated with earthquake nucleation. We examine the relationships among stressing history (loading path), initial conditions, and scaling of nucleation dimensions. Recent studies show that late‐stage expansion depends strongly on the ratio of the rate‐state parameters a and b. Increasing a/b to the limiting value of 1 favors expansion. We further find that initial conditions of frictional state θ and slip rate v strongly regulate the effect of a/b on nucleation‐zone expansion. Significant nucleation‐zone expansion is restricted to a narrow region around a critical point in the domain of initial conditions. The critical point marks a point of divergent paths of evolving slip rate and frictional state. Away from the critical point, nucleation‐zone expansion decreases rapidly and becomes rather weak. We conclude that evolution of θ and v in natural earthquake cycles generally follows paths that significantly restrict nucleation‐zone expansion, even for relatively large a/b values. This finding suggests that premonitory signals generated by a fast‐slipping nucleation zone immediately before earthquakes may be small and difficult to detect.
The central west Saharan dust hot spot and its relation to African easterly waves and extratropical disturbances
Authors: Knippertz Peter , Todd Martin C.
Published: June 2010

A vast, arid, and virtually uninhabited region covering eastern Mauritania and northern Mali appears in satellite estimates of dust loading as the global maximum during boreal summer. Here the complex meteorological conditions that create this central western Sahara (CWS) dust hot spot are investigated on the basis of regression analyses and case study examples using a wide range of satellite analysis products. The results confirm the importance of African easterly waves (AEWs), previously hypothesized on the basis of case studies. The main ingredients to create this connection are as follows. (1) Strengthened southerlies to the east of an AEW trough advect moist air into the southern Sahara. Daytime heating and orography trigger moist convection in this air mass. Strong evaporation in dry midlevel air generates extended cold pools and haboob dust storms. (2) Vertical mixing brings dust into the upper parts of the deep Saharan boundary layer, from where it can be advected back into the CWS region with the northerlies ahead of the next AEW trough. (3) If the associated surface vortex is strong enough, more dust emission occurs within or just upstream of the CWS. (4) High‐amplitude waves in the subtropics enhance the meridional flow associated with the AEW. Although there is a considerable case‐to‐case variability, it can be concluded that AEWs in concert with extratropical disturbances substantially contribute to the hot spot creation both through emission and the organization of transport. Disagreement between different satellite products and the presence of clouds complicate the analysis and underline the necessity for new observations.
Three‐dimensional charge structure of a mountain thunderstorm
Authors: Hager William W. , Aslan Beyza Caliskan , Sonnenfeld Richard G. , Crum Timothy D. , Battles John D. , Holborn Michael T. , Ron Ruth
Published: June 2010

Lightning charge transport is analyzed for a thunderstorm which occurred on 18 August 2004 near Langmuir Laboratory in New Mexico. The analysis employs wide band measurements of the electric field by a balloon‐borne electric field sonde or Esonde, simultaneous Lightning Mapping Array measurements of VHF pulses emitted during lightning breakdown, and Next Generation Weather Radar data. The thunderstorm was composed of two principal updrafts. In the stronger updraft the positively charged particles reached altitudes up to 14 km, and in the weaker updraft the positive particles reached 11 km altitude. The negatively charged particles generated in the updraft appeared to reach altitudes up to 10 km in the strong updraft and 8 km in the weaker updraft. Just outside the updrafts the positive and negative particles drop sharply; thereafter, they drop down at a nearly linear rate, between 1 and 2 km in altitude per 10 km in horizontal distance. Initially, as the updraft developed, most charge was transported by updraft flashes; later, after about 15 to 20 min, extensive flashes were predominant. Most cloud‐to‐ground (CG) flashes transported negative charge from outside the updraft at 6 km altitude down to ground; however, some strokes of a CG reached into a higher negative charge region closer to the updraft. Nearly 6 times as much charge was transported by intracloud (IC) flashes when compared to CG flashes. The ratio of the average charge transport for an IC flash to the average charge transport for a CG flash was 1.6, while the average generator current associated with the combined updrafts was 2.3 amperes for 40 min.
A comparison of Martian north and south polar cold spots and the long‐term effects of the 2001 global dust storm
Authors: Cornwall C. , Titus T. N.
Published: June 2010

In the 1970s, Viking and Mariner observed areas in the polar regions of Mars with winter brightness temperatures below the expected kinetic temperatures for CO2 ice sublimation. These areas have since been termed “cold spots” and have been identified as surface deposits of CO2 atmospheric condensates and, occasionally, active CO2 storms. Three Mars years of data from the Mars Global Surveyor Thermal Emission Spectrometer were used to observe autumn and winter cold spot activity. In this study, cold spots that occur near and on the southern perennial cap were compared to those found near or on the northern perennial cap. On the southern perennial cap, cold spots associated with topographic features (induced by orographic lifting) were less common than cold spots independent of topography, similar to the north. However, the cold spots in the south lasted longer than those observed in the north. There is also evidence that cold spot formation in the south was affected by the global dust storm of 2001, even though the dust storm occurred during the southern spring and summer seasons. Prior to the dust storm, the amount of overall cold spot activity closer to the perennial cap increased and the average CO2 grain size for most of the cold spots increased as well. Following the dust storm, the majority of cold spots in the south increased in size and duration but they did not form north of 62°S latitude, whereas, in other years, cold spots formed as far north as 48°S.
Effects of upstream dams versus groundwater pumping on stream temperature under varying climate conditions
Authors: Risley John C. , Constantz Jim , Essaid Hedeff , Rounds Stewart
Published: June 2010

The relative impact of a large upstream dam versus in‐reach groundwater pumping on stream temperatures was analyzed for humid, semiarid, and arid conditions with long dry seasons to represent typical climate regions where large dams are present, such as the western United States or eastern Australia. Stream temperatures were simulated using the CE‐QUAL‐W2 water quality model over a 110 km model grid, with the presence or absence of a dam at the top of the reach and pumping in the lower 60 km of the reach. Measured meteorological data from three representative locations were used as model input to simulate the impact of varying climate conditions on streamflow and stream temperature. For each climate condition four hypothetical streamflow scenarios were modeled: (1) natural (no dam or pumping), (2) large upstream dam present, (3) dam with in‐reach pumping, and (4) no dam with pumping, resulting in 12 cases. Dam removal, in the presence or absence of pumping, resulted in significant changes in stream temperature throughout the year for all three climate conditions. From March to August, the presence of a dam caused monthly mean stream temperatures to decrease on average by approximately 3.0°C, 2.5°C, and 2.0°C for the humid, semiarid, and arid conditions, respectively; however, stream temperatures generally increased from September to February. Pumping caused stream temperatures to warm in summer and cool in winter by generally less than 0.5°C because of a smaller pumping‐induced alteration in streamflow relative to the dam. Though the presence or absence of a large dam led to greater changes in stream temperature than the presence or absence of pumping, ephemeral conditions were increased both temporally and spatially because of pumping.
Effect of surficial disturbance on exchange between groundwater and surface water in nearshore margins
Authors: Rosenberry Donald O. , Toran Laura , Nyquist Jonathan E.
Published: June 2010

Low‐permeability sediments situated at or near the sediment‐water interface can influence seepage in nearshore margins, particularly where wave energy or currents are minimal. Seepage meters were used to quantify flow across the sediment‐water interface at two lakes where flow was from surface water to groundwater. Disturbance of the sediment bed substantially increased seepage through the sandy sediments of both lakes. Seepage increased by factors of 2.6 to 7.7 following bed disturbance at seven of eight measurement locations at Mirror Lake, New Hampshire, where the sediment representing the greatest restriction to flow was situated at the sediment‐water interface. Although the veneer of low‐permeability sediment was very thin and easily disturbed, accumulation on the bed surface was aided by a physical setting that minimized wind‐generated waves and current. At Lake Belle Taine, Minnesota, where pre‐disturbance downward seepage was smaller than at Mirror Lake, but hydraulic gradients were very large, disturbance of a 20 to 30 cm thick medium sand layer resulted in increases in seepage of 2 to 3 orders of magnitude. Exceptionally large seepage rates, some exceeding 25,000 cm/d, were recorded following bed disturbance. Since it is common practice to walk on the bed while installing or making seepage measurements, disruption of natural seepage rates may be a common occurrence in nearshore seepage studies. Disturbance of the bed should be avoided or minimized when utilizing seepage meters in shallow, nearshore settings, particularly where waves or currents are infrequent or minimal.
In‐situ permeability from integrated poroelastic reflection coefficients
Authors: van Dalen Karel N. , Ghose Ranajit , Drijkoningen Guy G. , Smeulders David M. J.
Published: June 2010

A reliable estimate of the in‐situ permeability of a porous layer in the subsurface is extremely difficult to obtain. We have observed that at the field seismic frequency band the poroelastic behavior for different seismic wavetypes can differ in such a way that their combination gives unique estimates of in‐situ permeability and porosity simultaneously. This is utilized in the integration of angle‐ and frequency‐dependent poroelastic reflection coefficients in a cost function. Realistic numerical simulations show that the estimated values of permeability and porosity are robust against uncertainties in the employed poroelastic mechanism and in the data. Potential applications of this approach exist in hydrocarbon exploration, hydrogeology, and geotechnical engineering.
Homology modeling and monoclonal antibody binding of the Der f 7 dust mite allergen
Authors: Shen Horng‐Der , Tam Ming F , Huang Chao‐Hsien , Chou Hong , Tai Hsiao‐Yun , Chen Yu‐Sen , Sheu Sheh‐Yi , Thomas Wayne R
Published: June 2010

The group 7 allergens are important allergenic specificities for mite‐sensitive patients and may need to be incorporated into new diagnostic and therapeutic strategies. However, little is known about their biological and structural features. Position‐specific iterative BLAST showed that they had strong ancestral homology to two related families of lipid‐binding proteins, namely, the bactericidal permeability‐increasing (BPI) proteins and the odorant‐binding protein. A three‐dimensional model of Der f 7 made with the Phyre and SWISS‐MODEL homology‐modeling servers showed a close match with the human BPI coordinates used for its construction. The binding of the monoclonal antibody HD12 known to block IgE binding could be blocked by the linear sequence (46GILDF50) with a critical role for L48 or F50. These hydrophobic residues were located on a surface loop of the model. The properties of Der f 7 that can be deduced from the model provide avenues for further characterizing these allergens, their IgE binding structures and biological properties that can enhance allergenicity.
Activating and inhibitory receptors of natural killer cells
Authors: Pegram Hollie J , Andrews Daniel M , Smyth Mark J , Darcy Phillip K , Kershaw Michael H
Published: June 2010

Natural killer (NK) cells are potent immune effector cells that can respond to infection and cancer, as well as allowing maternal adaptation to pregnancy. In response to malignant transformation or pathogenic invasion, NK cells can secrete cytokine and may be directly cytolytic, as well as exerting effects indirectly through other cells of the immune system. To recognize and respond to inflamed or infected tissues, NK cells express a variety of activating and inhibitory receptors including NKG2D, Ly49 or KIR, CD94–NKG2 heterodimers and natural cytotoxicity receptors, as well as co‐stimulatory receptors. These receptors recognize cellular stress ligands as well as major histocompatibility complex class I and related molecules, which can lead to NK cell responses. Importantly, NK cells must remain tolerant of healthy tissue, and some of these receptors can also prevent activation of NK cells. In this review, we describe the expression of prominent NK cell receptors, as well as expression of their ligands and their role in immune responses. In addition, we describe the main signaling pathways used by NK cell receptors. Although we now appreciate that NK cell biology is more complicated than first thought, there are still facets of their biology that remain unclear. These will be highlighted and discussed in this review.
Tumstatin45‐132‐TNFα suppresses tumour growth through anti‐angiogenic effects and cytotoxicity
Authors: Yan Yongmin , Xu Wenrong , Qian Hui , Zhu Wei , Mao Fei , Zhang Xu
Published: June 2010

Tumstatin45‐132 is an 88‐amino‐acid fragment possessing the equivalent ability of full‐length tumstatin to block new tumour blood‐vessel formation and suppress tumour growth. TNFα (tumour necrosis factor α), an antitumour agent, is used in clinical therapy, but is limited by its strong systemic toxicity. Combining TNFα with tumstatin45‐132 may represent a promising alternative approach in cancer therapy. In the present study, we expressed recombinant tumstatin45‐132‐TNFα in a baculovirus expression system. We evaluated the effects of tumstatin45‐132‐TNFα on neovascularization and cell viability by a chick‐embryo‐chorioallantoic‐membrane assay and a 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyl‐2H‐tetrazolium bromide assay. In‐vivo antitumour activities were examined in tumour‐bearing mice. We observed that tumstatin45‐132‐TNFα inhibited angiogenesis and tumour‐cell viability in vitro. In‐vivo experiments showed that intratumoural injection of tumstatin45‐132‐TNFα significantly inhibited the growth of xenograft tumours in mice. MRI analysis revealed that tumstatin45‐132‐TNFα treatment also decreased mean blood‐vessel density in vivo. Tumstatin45‐132‐TNFα exerted antitumour activities by decreasing proliferation, inducing apoptosis in tumour cells and anti‐angiogenesis. In conclusion, our findings suggest that tumstatin45‐132‐TNFα has significant activity against F6 tumour cells and that it may be a potential approach for cancer therapy.
Relationships between atmospheric organic compounds and air-mass exposure to marine biology
Authors: Arnold S. R. , Spracklen D. V. , Gebhardt S. , Custer T. , Williams J. , Peeken I. , Alvain S.
Published: June 2010

Environmental context.The exchange of gases between the atmosphere and oceans impacts Earth’s climate. Over the remote oceans, marine emissions of organic species may have significant impacts on cloud properties and the atmosphere’s oxidative capacity. Quantifying these emissions and their dependence on ocean biology over the global oceans is a major challenge. Here we present a new method which relates atmospheric abundance of several organic chemicals over the South Atlantic Ocean to the exposure of air to ocean biology over several days before its sampling.
Abstract.We have used a Lagrangian transport model and satellite observations of oceanic chlorophyll-a concentrations and phytoplankton community structure, to investigate relationships between air mass biological exposure and atmospheric concentrations of organic compounds over the remote South Atlantic Ocean in January and February 2007. Accounting for spatial and temporal exposure of air masses to chlorophyll from biologically active ocean regions upwind of the observation location produces significant correlations with atmospheric organohalogens, despite insignificant or smaller correlations using commonly applied in-situ chlorophyll. Strongest correlations (r = 0.42–0.53) are obtained with chlorophyll exposure over a 2-day transport history for CHBr3, CH2Br2, CH3I, and dimethylsulfide, and are strengthened further with exposure to specific phytoplankton types. Incorporating daylight and wind-speed terms into the chlorophyll exposure results in reduced correlations. The method demonstrates that conclusions drawn regarding oceanic trace-gas sources from in-situ chlorophyll or satellite chlorophyll averages over arbitrary areas may prove erroneous without accounting for the transport history of air sampled.
Quantitative determination of fullerene (C60) in soils by high performance liquid chromatography and accelerated solvent extraction technique
Authors: Shareef Ali , Li Guihua , Kookana Rai S.
Published: June 2010

Environmental context.Due to the increasing adoption of nanotechnology, synthetic nanoparticles such as fullerenes (nC60), are likely to emerge as contaminants in aquatic and terrestrial environments. Currently, our understanding of the fate and effects of C60 in the terrestrial environment is poor and is primarily hampered by the lack of reliable quantitative analytical methods. In this paper, we describe a method for effective extraction and sensitive detection of C60 residues in soils which will facilitate environmental fate studies on nC60.
Abstract.Fullerenes (e.g. C60) are emerging as environmental contaminants due to their wide range of applications, such as in optics, electronics, cosmetics and biomedicine. Residue analysis is a crucial step in understanding the fate and effects of C60 in the terrestrial environments. However, there is a lack of reliable quantitative analytical methods for extraction and analysis of C60 in soils or sediments. We developed a method for determination of C60 in soils using accelerated solvent extraction (ASE) followed by HPLC-UV detection. Separation of C60 from soil matrix interferences was achieved by gradient elution using methanol–toluene mobile phase. Mean recoveries obtained from extraction efficiency tests using six contrasting soils spiked (wet and dry tests with freeze drying of wet and aged soils before ASE) at varying concentrations of C60 ranged from 84 to 107%. The current method provides adequate sensitivity (limit of quantitation = 20 μg kg–1), and can be used for quantitative determination of C60 in soils and sediments (especially for environmental fate studies) without needing expensive HPLC-mass spectrometry.
Matrix-bound phosphine in paddy fields under a simulated increase in global atmospheric CO2
Authors: Zhang J. , Geng J. J. , Zhang R. , Ren H. Q. , Wang X. R.
Published: June 2010

Environmental context. Although phosphine (PH3) is an important gaseous carrier in the phosphorus cycle, its production and environmental behaviour remain unclear. Paddy fields are thought to be one of the main sources responsible for the production and emission of PH3. Understanding the behaviour of PH3 in paddy fields under elevated CO2 concentration is crucial in understanding the phosphorus cycle and its response to rising global atmospheric CO2 concentration.
Abstract. The behaviour of matrix-bound phosphine (MBP) in paddy fields under elevated [CO2] (ambient + 200 μmol mol–1) is investigated to understand the soil phosphorus cycle and its link to increasing global atmospheric [CO2]. MBP concentrations range from 17.0 ± 5.8 to 1035 ± 331 ng kg–1. Concentrations at the transplanting and harvest stages are significantly higher than during the growing stages. The MBP level (212 ± 61 ng kg–1) under elevated [CO2] is slightly higher than under ambient [CO2] (189 ± 44 ng kg–1). Root exudates and addition of inorganic phosphate fertiliser speed up the production of MBP, whereas fast paddy growth and increasing air temperature accelerate the emission of MBP into the atmosphere. Significant positive correlations are found between MBP and inorganic phosphorus and organic matter, indicating that MBP may be produced from the microbial reduction of inorganic phosphorus in paddy fields.
Cu and Pb accumulation by the marine diatom Thalassiosira weissflogii in the presence of humic acids
Authors: Sánchez-Marín Paula , Slaveykova Vera I. , Beiras Ricardo
Published: June 2010

Environmental context.Dissolved organic matter protects aquatic microorganisms from toxic metals by complexing and decreasing the concentration of the biologically reactive species such as free metal ions. However, there are some cases of enhancement of toxic effects when humic acids are present, which is thought to be due to effects of adsorbed humic acids on cell membranes. For a marine diatom, humic acids adsorbed to cell surfaces enhanced metal adsorption, whereas intracellular metal contents decreased as a result of metal binding by humic acids. These findings suggest that the diatom wall, the frustule, presents a barrier against direct effects of adsorbed humic acids on the plasma membrane.
Abstract.Metal complexation by dissolved organic matter, as humic acids, is considered to decrease metal bioavailability by lowering the free metal ion concentration. However, dissolved organic matter adsorption on cell surfaces can modify cell membrane properties, which can also influence metal uptake. Copper and lead accumulation and internalisation by the marine diatom Thalassiosira weissflogii were studied in the absence and presence of humic acids, and adsorption of humic acids to cell surfaces was evaluated. Both Pb and Cu intracellular concentrations decreased in the presence of humic acids according to labile metal concentrations measured by anodic stripping voltammetry, whereas total (intracellular plus adsorbed) metal content was enhanced in the presence of humic acids, probably owing to enhanced metal plus humics adsorption to cell surfaces. The results of the present work stress the importance of differentiating between intracellular and total cellular metal in bioavailability studies, and suggest that the silica frustule of diatoms represents a barrier against humic acids effects on cell membranes.