bluuebunny/crossref_metadata_2025 huggingface dataset:
Response of degradative enzymes to N fertilization during litter decomposition in a subtropical forest through a microcosm experiment
Authors: Wang Congyan , Feng Xiaoguang , Guo Peng , Han Guomin , Tian Xingjun
Published: June 2010

With the continuing increase in human activities causing accelerating rates of anthropogenic nitrogen deposition inputs into forests, there is considerable interest in understanding the effects of nitrogen deposition on litter decomposition. Two dominant litters were chosen from Zijin Mountain in China: Quercus acutissima from a broad‐leaved forest and Pinus massoniana from a coniferous forest. The litters were incubated in microcosms and treated with a gradient of nitrogen fertilization. During a 6‐month incubation, changes in chemical composition (i.e., lignin, total carbohydrate, and nitrogen), litter mass losses, soil pH values, and the activities of degradative enzymes were determined. Results showed that medium‐nitrogen and high‐nitrogen fertilization significantly accelerated litter decomposition rates of leaves, while only the high‐nitrogen fertilization significantly accelerated litter decomposition rates of needles. The results also showed that cellulase and nitrate reductase were primarily responsible for litter decomposition in the broad‐leaved forest, while catalase, cellulase, and acid phosphatase were primarily responsible for litter decomposition in the coniferous forest under conditions of no N fertilization; catalase, cellulase, and acid phosphatase were primarily responsible for litter decomposition in the broad‐leaved forest, while catalase, cellulase, invertase, and nitrate reductase were primarily responsible for litter decomposition in the coniferous forest under conditions of N fertilization. Nitrogen fertilization‐stimulated litter decomposition was due to the fact that the activities of enzymes, particularly cellulase, were accelerated.
Influence of the Mixed Propoxy/Ethoxy Spacer Arrangement Order and of the Ionic Head Group Nature on the Adsorption and Aggregation of Extended Surfactants
Authors: Forgiarini Ana M. , Scorzza Cesar , Velásquez Josmary , Vejar Francia , Zambrano Emérita , Salager Jean‐Louis
Published: June 2010

Two families of extended surfactants were prepared with the same head groups (carboxylate, sulfate, disodium phosphate) and different intermediate spacer structures. In one there was an average of 7 propylene oxide groups on the side of the tail and an average of 7 ethylene oxide groups on the side of the head, to produce a sequence of two different polarity segments. In the other case the spacer contained the same average numbers of propylene and ethylene oxide groups but in some homogeneous arrangement. The intermediate spacer structure, without ionic head group and in the cases of the carboxylate and sulfate extended surfactants, had a packing density reduction which is associated to the homogeneously alkoxide arrangement in the spacer. Such an arrangement was found to produce about 20% more surface area at the interface, apparently because it results in some plumpness due to the spacer folding to remain close to the interface. Both the critical micelle concentration and occupied interfacial area of the extended surfactant increased with the ionization of the anionic group associated with the electrostatic repulsion effect.
Publishing in Marketing Journals by Australia and New Zealand Academics 1999-2003: An Examination of Institutional Performance
Authors: Polonsky Michael , Mittelstaedt John , Moore Jesse
Published: June 2010

This paper examines publishing performance by academics in Australian and New Zealand universities between 1999 and 2003. Two sets of journals are examined, the leading 30 marketing journals as defined by senior Australian and New Zealand academics (Mort et al. 2004) and the leading 20 marketing journals as identified by a cross-section of American academics (Polonsky and Whitelaw 2006). Comparisons in publication performance are made between seven institutional groupings, Group of 8, New Zealand Universities, Technology Network Universities, Regional Universities, Innovation Universities, New Generation Universities and Private Universities, using these two sets of journals. The comparisons identify that the Australian G8 institutions outperform other groupings. However, there are many similarities in performance between other groupings, especially when sub-sets of journals were examined. Thus, research performance within marketing may be more similar than is generally purported in the popular press.
The Influence of Culture on Retail Sales Promotion Use in Chinese Supermarkets
Authors: McNeill Lisa S.
Published: June 2010

Current challenges to supermarket retailers posed by the growing popularity of online retail, customer desensitisation to advertising, and globalisation of large grocery retail firms, has led to an increased reliance on sales promotion as a means of attracting and retaining customers. Retailers recognise the need to make the shopping experience more rewarding for the consumer (Keh and Teo 2001), and have a keen understanding of which supplementary activities are likely to achieve this in their market. The difficulty faced by manufacturers, therefore, is in assessing which sales promotion activities that support their own goals will be favoured by retailers in culturally diverse environments. In light of China's attractiveness as an export destination for food products (Lo et al 2001), those wishing to do business effectively in China must understand specifically how sales promotion and culture are linked (Lee 2002). This exploratory study considers the use of, and preferences towards, different sales promotion methods in supermarkets in China and New Zealand, highlighting the potential impact of cultural influence on the application of particular tools.
Comparing Structural Equation Models with Discrete Choice Experiments for Modelling Brand Equity and Predicting Brand Choices
Authors: Wang Paul Z. , Menictas Constantinos , Louviere Jordan J.
Published: June 2010

Brands play an important role in consumers’ perception and choice of a product. Measuring brand equity has thus become a topic of growing interest among both practitioners and researchers in marketing. This paper examines the Erdem and Swait (1998) brand equity framework, which is one of the key consumer-based brand equity models developed in the brand literature. Specifically, it investigates the external validity of the Erdem-Swait framework using two alternative approaches: One is based on structural equation models (SEMs) and the other is based on discrete choice experiments (DCE). Four data sets pertaining to four different product categories were collected from the Australian financial services sector to compare the ability of expected utilities calculated from SEMs and DCEs to predict the actual brand choices of real consumers in real markets. Although both models performed well, results showed that the predictions of the DCE models were consistently better than those of the SEMs in all cases. These findings have implications for both academics and practitioners in brand evaluation and management.
Question Stability in Brand Image Measurement: Comparing Alternative Answer Formats and Accounting for Heterogeneity in Descriptive Models
Authors: Dolnicar Sara , Grün Bettina
Published: June 2010

High quality image data on how consumers perceive brands is essential to make good brand management decisions. Prior studies reveal that brand images are not very reliable, as they are typically measured in industry, which might be due to the answer format typically used (Rungie et al., 2005). The practical implication is that brand image data — as currently collected in consumer surveys — is not a valid source of market information. We challenge this implication.

Using three measures of stability we test whether the binary answer format produces image data less reliable than alternative formats. We investigate whether the aggregate descriptive model of brand image stability proposed by Rungie et al. can be improved by accounting for heterogeneity.

Results indicate that, compared to alternative formats, binary answer formats lead to equal stability levels, and most brand-attribute associations are stable. Unstable associations typically fail to describe adequately the brands under study.

Practical implications include that binary brand-attribute associations can be used safely to measure brand images. Also, practitioners can get guidance about required brand management measures by discriminating between stable and unstable brand-attribute associations. A model that helps managers classify brand-attribute associations into stable or unstable is proposed in the article.
A Multiple Case Analysis of Franchised Co-Branding
Authors: Wright Owen , Frazer Lorelle
Published: June 2010

Retail co-branding is an increasingly popular form of growth in a maturing Australian franchising sector. This paper presents an exploratory study of franchised retail co-branding arrangements utilising a case study approach. The existing literature, which has previously focused on product-specific co-branding, is extended. Traditional co-branding, agent theoretic and resource constraint arguments are analysed and found to be inadequate when applied to this new phenomenon. The research reveals that the motivations for introducing co-brands into existing franchises include alignment of a suitable brand with existing retail formats, risk aversion by the franchisor to the use of externally owned brands, reinvigorating the brands, and stimulating sales growth for specific outlets. In addition the research shows that co-brands can be successfully created internally franchisors are willing to sacrifice the culture and concept of the original franchise brand in order to achieve system growth.
Branding of Prescription Medicines to Australian Consumers
Authors: Hall Danika V. , Jones Sandra C.
Published: June 2010

Brand development and brand management is complex in the pharmaceutical sector due to the specific nature of pharmaceutical products and their life-cycles, as well as the regulation of promotional activity. The building of strong brands is becoming increasingly important for the industry, and consideration is being given to developing more expressive or emotional values of brands over traditional functional values and attributes. In Australia, brand-building activity for prescription pharmaceuticals primarily targets the medical profession in an effort to achieve brand recognition, brand preference and brand loyalty and, in turn, increase prescriptions. Despite direct-to-consumer-advertising of prescription pharmaceuticals not being allowed in Australia, there have been cases of unnamed product advertisements and disease awareness campaigns that serve to increase consumer awareness of brands within a category. This paper provides a review of issues influencing brand building in the pharmaceutical sector as well as recent examples of brand-building activities that target Australian consumers.
Branding in the Non-Profit Context: The Case of Surf Life Saving Australia
Authors: Mort Gillian Sullivan , Weerawardena Jay , Williamson Brett
Published: June 2010

Whilst brand management as a specific sub-field of marketing management is well developed in business research, it is still an emerging area in non-profit organisations. Non-profit organisations are faced with distinct brand challenges, which include issues related to multiple stakeholders in managing the brand and the need to negotiate partnering and sponsorship arrangements. Newly established non-profit organisations can begin their organisational development with strong branding strategies, however many established non-profit organisations have a strong brand heritage, which requires special preservation, renewal and extension strategies. This paper uses a case study methodology to examine the branding issues in Surf Life Saving Australia, a volunteer community beach safety organisation that holds a unique position in the Australian community and cultural psyche, which nevertheless must continually renew and extend its brand heritage in order to achieve its evolving organisational objectives. While the organisation is unique, the paper identifies issues in stakeholder brand management and brand preservation, renewal and extension with wider theoretical and practical implications for non-profit organisations and contemporary perspectives on branding.
Marketing as an Interaction System
Authors: Varey Richard J.
Published: June 2010

Marketing thinkers identify concepts of relationship, interaction, and network as useful. Edgar Crane (1972) saw interaction as essential to buyer-seller decision-making. David Ford, Kristian Möller, and Håkan Håkansson followed with explanations of how marketing operates. Christian Grönroos expanded the horizon with ‘interactive marketing’. Evert Gummesson saw interaction as “active contact” and all marketing as relationships and interaction in networks. The Relationship Marketing field flourished – at least for a time.

Whilst many proponents of “interactive communication” and “social interaction” do not see the interaction concept as problematic, they focus attention on practices. I choose to re-examine both ‘interaction’ and ‘communication’, and to relate these concepts to the concepts of society and the social process we call “marketing”.

The discussion proceeds from the general perspective of humans living among others, to the specific situation of marketing in society. I examine the concept of ‘interaction’, and consider social interaction as exchange –a dialogical view of human communication. The patterning of social interaction in markets as distinct from bureaucracies, solidarity groupings, and co-operative collectives is examined.

An alternative sociological analysis of the social is compared with that of the social psychology tradition. Communication is discussed as a mode of interaction, to reveal monologic (technical) and dialogic (humanitarian) conceptions of communication prevalent in the marketing field.

Within the context of an ‘Interaction Society’, marketing is explained as a complex dynamic adaptive interaction system, revealing a conversational nature. It is proposed that interaction directs and co-ordinates, but also co-creates – ‘interactional work’ has innovative capacity.
ALGEBRAIC VALUES OF TRANSCENDENTAL FUNCTIONS AT ALGEBRAIC POINTS
Authors: HUANG JINGJING , MARQUES DIEGO , MEREB MARTIN
Published: June 2010

It is shown that any subset of $\overline {\mathbb {Q}}$ can be the exceptional set of some transcendental entire function. Furthermore, we give a much more general version of this theorem and present a unified proof.
PRESENTATION FOR RENNER MONOIDS
Authors: GODELLE EDDY
Published: June 2010

We extend the result obtained in E. Godelle [‘The braid rook monoid’, Internat. J. Algebra Comput.18 (2008), 779–802] to every Renner monoid: we provide a monoid presentation for Renner monoids, and we introduce a length function which extends the Coxeter length function and which behaves nicely.
ON THE DIOPHANTINE EQUATIONz2=f(x)2±f(y)2, II
Authors: HE BO , TOGBÉ ALAIN , ULAS MACIEJ
Published: June 2010

Letf∈ℚ[X] and let us consider a Diophantine equationz2=f(x)2±f(y)2. In this paper, we continue the study of the existence of integer solutions of the equation, when the degree offis 2 and iff(x) is a triangular number or a tetrahedral number.
Presence or absence of carbohydrates and the proportion of fat in a high-protein diet affect appetite suppression but not energy expenditure in normal-weight human subjects fed in energy balance
Authors: Veldhorst Margriet A. B. , Westerterp Klaas R. , van Vught Anneke J. A. H. , Westerterp-Plantenga Margriet S.
Published: June 2010

Two types of relatively high-protein diets, with a normal or low proportion of carbohydrates, have been shown effective for weight loss. The objective was to assess the significance of the presence or absence of carbohydrates and the proportion of fat in high-protein diets for affecting appetite suppression, energy expenditure, and fat oxidation in normal-weight subjects in energy balance. Subjects (aged 23 (sd3) years and BMI 22·0 (sd1·9) kg/m2) were stratified in two groups. Each was offered two diets in a randomised cross-over design: group 1 (n22) – normal protein (NP; 10, 60 and 30 % energy (En%) from protein, carbohydrate and fat), high protein (HP; 30, 40 and 30 En%); group 2 (n23) – normal protein (NP-g; 10, 60 and 30 En%), high protein, carbohydrate-free (HP-0C; 30, 0 and 70 En%) for 2 d; NP-g and HP-0C were preceded by glycogen-lowering exercise (day 1). Appetite was measured throughout day 2 using visual analogue scales (VAS). Energy expenditure (EE) and substrate oxidation (respiratory quotient; RQ) were measured in a respiration chamber (08.00 hours on day 2 until 07.30 hours on day 3). Fasting plasma β-hydroxybutyrate (BHB) concentration was measured (day 3). NP-g and NP did not differ in hunger, EE, RQ and BHB. HP-0C and HPv.NP-g and NP, respectively, were lower in hunger (P < 0·05;P < 0·001) and RQ (P < 0·01;P < 0·001) and higher in EE (P < 0·05;P = 0·07) and BHB (P < 0·05;P < 0·001). Hunger and RQ were lower with HP-0C than HP (693 (sd208)v.905 (sd209) mm VAS × 24 h,P < 0·01; 0·76 (sd0·01)v. 0·81 (sd0·02),P < 0·01); BHB was higher (1349 (sd653)v.332 (sd102) μmol/l;P < 0·001). ΔHunger, ΔRQ, and ΔBHB were larger between HP-0C–NP-g than between HP–NP ( − 346 (sd84)v.− 107 (sd52) mm VAS ×  24 h,P < 0·01; − 0·09 (sd0·00)v.− 0·05 (sd0·00),P < 0·001; 1115 (sd627)v.104 (sd42) μmol/l,P < 0·001). In conclusion, appetite suppression and fat oxidation were higher on a high-protein diet without than with carbohydrates exchanged for fat. Energy expenditure was not affected by the carbohydrate content of a high-protein diet.
Modern Art Patronage and Democratic Citizenship in Japan
Authors: Hein Laura
Published: June 2010

Wakimura Yoshitarō, a prominent Japanese economics professor and art collector, helped establish or sustain at least eight art museums in postwar Japan. He did so to create important institutions of democratic empowerment rather than nationalist displays of power. The crucial context was defeat in World War II, which left many Japanese, including Wakimura, committed to taming capitalism. Wakimura was particularly interested in creating new practices of art appreciation that could mediate relations between potentially antagonistic groups of Japanese, and in building museums as fresh spaces to house these newly egalitarian relationships. He emphasized the value to society created when individuals developed their aesthetic and thus political judgment. His efforts help explain the proliferation of both public and private art museums in postwar Japan as well as the nature of postwar political culture.
Expo 2010: A Historical Perspective
Authors: Fernsebner Susan R.
Published: June 2010

A remodeled city awaits Shanghai's visitors this summer. As always, tourists will crowd the famous Bund and enjoy the classic architecture erected by the International Settlement's foreign powers during an earlier day of cosmopolitanism and imperialism. Recently, Shanghai's city planners have undertaken a major project in remodeling the urban landscape that surrounds the Bund, with its old Hong Kong and Shanghai banks, Custom House, and grand hotels built during the late nineteenth and early twentieth centuries. In doing so, planners have effectively transformed this waterfront symbol of China's former semicolonial status into a breezy park, sightseeing plaza, and high-end shopping district, all rolled into one. The classic architecture of the treaty port era has become the backdrop for a new day's consumerism, perfectly suited to the Chinese state's own celebration of the successes of a reform economy.
Nice sets and invariant densities in complex dynamics
Authors: DOBBS NEIL
Published: June 2010

In complex dynamics, we construct a so-called nice set (one for which the first return map is Markov) around any point which is in the Julia set but not in the post-singular set, adapting a construction of Rivera–Letelier. This simplifies the study of absolutely continuous invariant measures. We prove a converse to a recent theorem of Kotus and Świątek, so for a certain class of meromorphic maps the absolutely continuous invariant measure is finite if and only if an integrability condition is satisfied.
Introduction: The Otto Scherzer Special Issue on Aberration-Corrected Electron Microscopy
Authors: Smith David J. , Dahmen Uli
Published: June 2010

The year 2009 marked the centenary of the birth of Otto Scherzer, one of the early pioneers of electron microscopy. Scherzer was the originator of the famous microscopy theorem that the spherical and chromatic aberrations of rotationally symmetric electron lenses were unavoidable. In honor of this centennial occasion, we organized a special memorial symposium during Microscopy & Microanalysis 2009, which was held in Richmond, Virginia, in late July. The introductory talks of the symposium presented a fascinating mix of first-hand accounts about working with Scherzer in Darmstadt and descriptions of the correction concepts and the early corrector prototypes that emerged from his group. Placed in this historical context, the latest advances in aberration correction for scanning and fixed-beam instruments that were presented in this symposium were all the more impressive and conveyed a vivid sense of history in the making. Applications of aberration correction to a broad range of materials were also highlighted in platform and poster presentations. This special issue of Microscopy and Microanalysis contains refereed contributions from the work presented at the symposium and thus provides a representative overview of the recent emergence of aberration-corrected electron microscopy (ACEM) and some of the prospects and challenges for this burgeoning field.
Understanding recent increases in chronic disease treatment rates: more disease or more detection?
Authors: Howard David H. , Thorpe Kenneth E. , Busch Susan H.
Published: June 2010

The proportion of the population treated for major medical conditions, including diabetes, cancer and mental illness, increased rapidly during the 1990s. We document the magnitude of these increases and use a model of prevalence to identify three potential causes: increased clinical incidence of disease, longer survival times among persons with chronic illnesses and increased detection. We present a series of analyses to evaluate the contribution of each factor. We find that increases in obesity explain a large proportion of the increase in treatment rates for conditions closely linked to obesity (e.g. diabetes). We provide some evidence that increases in treated prevalence unexplained by changes in the underlying clinical incidence of disease are driven by increased detection and treatment of patients with ‘subclinical’ illness.
How Italian regulatory policy encounters Europe
Authors: Natalini Alessandro
Published: June 2010

Improvement of regulatory quality has become one of the most important items on the European Union’s (EU) Lisbon Strategy for Growth and Jobs. In this context, the European Commission has sought to influence the regulatory reform policies of the Member States, focusing on the implementation of better regulation principles and tools. This article explores the interactive nature of Europeanization, viewing domestic institutions as ‘users’ of European policies according to their strategies. The author performs a within-case study based on a bottom–up research design, analysing the impact of EU better regulation on Italy. The results show that the effects of Europeanization relate more to agenda setting than to implementation – the latter is still, prevalently, determined by domestic factors.
Ion transport in Titan's upper atmosphere
Authors: Cui J. , Galand M. , Yelle R. V. , Wahlund J.‐E. , Ågren K. , Waite J. H. , Dougherty M. K.
Published: June 2010

Based on a combined Cassini data set including Ion Neutral Mass Spectrometer, Radio Plasma Wave Science, and Magnetometer measurements made during nine close encounters of the Cassini spacecraft with Titan, we investigate the electron (or total ion) distribution in the upper ionosphere of the satellite between 1250 and 1600 km. A comparison of the measured electron distribution with that in diffusive equilibrium suggests global ion escape from Titan with a total ion loss rate of ∼(1.7 ± 0.4) × 1025 s−1. Significant diurnal variation in ion transport is implied by the data, characterized by ion outflow at the dayside and ion inflow at the nightside, especially below ∼1400 km. This is interpreted as a result of day‐to‐night ion transport, with a horizontal transport rate estimated to be ∼(1.4 ± 0.5) × 1024 s−1. Such an ion flow is likely to be an important source for Titan's nightside ionosphere, as proposed in Cui et al. [2009a].
Application of the BISQ model to clay squirt flow in reservoir sandstones
Authors: Marketos G. , Best A. I.
Published: June 2010

An understanding of the variations of compressional wave velocity and attenuation in sandstones as a function of pore‐fluid properties is important for the identification and monitoring of hydrocarbon reservoirs. In order for seismic inversion to be well constrained a rock physics model that describes accurately the observed behavior is required; a number of such models have been proposed but have not been extensively tested against laboratory data. The unified Biot and squirt flow model was applied to data obtained from ultrasonic experiments conducted on a wide range of sandstone types when saturated with different pore fluids with viscosities ranging from 0.3 to 1000 cP. This model was seen to match well all the observed velocity and attenuation values as opposed to the Biot model, which was only successful for clean sandstones saturated with low viscosity fluids. This has led to the conclusion that a squirt flow mechanism is important at the grain scale. In addition, an increase in the dynamic uniaxial strain modulus of the dry frame with increasing pore‐fluid viscosity was observed. In the absence of free gas or grain contact microcracks (the laboratory data were collected at 60 MPa effective pressure), this can be linked to decreasing local flow and decreasing relaxation in the soft pore space of the sandstone, the extent of which is in turn connected to the clay content and pore structure of the sandstone. These results imply that at ultrasonic frequencies the squirt‐flow is due to the presence of clay.
Density measurement of Fe3C liquid using X‐ray absorption image up to 10 GPa and effect of light elements on compressibility of liquid iron
Authors: Terasaki H. , Nishida K. , Shibazaki Y. , Sakamaki T. , Suzuki A. , Ohtani E. , Kikegawa T.
Published: June 2010

Density of liquid iron alloy under high pressure is important to constrain the amount of light elements in the Earth’s core. Density measurement of solid and liquid Fe3C was performed using X‐ray absorption image technique up to 9.5 GPa and 1973 K. Density of liquid Fe3C increases from 6.94 g/cm3 to 7.38 g/cm3 with a pressure of 3.6–9.5 GPa at 1973 K. The bulk modulus of liquid Fe3C is obtained to be 50 ± 7 GPa at 1973 K. The effect of carbon on the compressibility of liquid iron is similar to that of sulfur, which significantly decreases the bulk modulus of liquid iron. Since carbon dissolution into liquid iron causes reduction of ρ and K0T, carbon could be excluded from the candidates of alloying light elements in the Earth’s outer core.
Unsteady high‐pressure flow experiments with applications to explosive volcanic eruptions
Authors: Orescanin M. M. , Austin J. M. , Kieffer S. W.
Published: June 2010

Motivated by the hypothesis that volcanic blasts can have supersonic regions, we investigate the role of unsteady flow in jets from a high‐pressure finite reservoir. We examine the processes for formation of far‐field features, such as Mach disk shocks, by using a shock tube facility and numerical experiments to investigate phenomena to previously unobtained pressure ratios of 250:1. The Mach disk shock initially forms at the edges of the vent and moves toward the centerline. The shock is established within a few vent diameters and propagates downstream toward the equilibrium location as the jet develops. The start‐up process is characterized by two different timescales: the duration of supersonic flow at the nozzle exit and the formation time of the Mach disk shock. The termination process also is characterized by two different timescales: the travel time required for the Mach disk shock to reach its equilibrium position and the time at which the Mach disk shock begins significantly to collapse away from its equilibrium position. The critical comparisons for the formation of steady state supersonic regions are between the two start‐up timescales and the termination timescales. We conclude that for typical vulcanian eruptions and the Mount St. Helens directed blast, the Mach disk shock could have formed near the vent, and that there was time for it to propagate a distance comparable to its equilibrium location. These experiments provide a framework for analysis of short‐lived volcanic eruptions and data for benchmarking simulations of jet structures in explosive volcanic blasts.
Water‐stable isotopes in the LMDZ4 general circulation model: Model evaluation for present‐day and past climates and applications to climatic interpretations of tropical isotopic records
Authors: Risi Camille , Bony Sandrine , Vimeux Françoise , Jouzel Jean
Published: June 2010

We present simulations of water‐stable isotopes from the LMDZ general circulation model (the LMDZ‐iso GCM) and evaluate them at different time scales (synoptic to interannual). LMDZ‐iso reproduces reasonably well the spatial and seasonal variations of both δ18O and deuterium excess. When nudged with reanalyses, LMDZ‐iso is able to capture the synoptic variability of isotopes in winter at a midlatitude station, and the interannual variability in mid and high latitudes is strongly improved. The degree of equilibration between the vapor and the precipitation is strongly sensitive to kinetic effects during rain reevaporation, calling for more synchronous vapor and precipitation measurements. We then evaluate the simulations of two past climates: Last Glacial Maximum (21 ka) and Mid‐Holocene (6 ka). A particularity of LMDZ‐iso compared to other isotopic GCMs is that it simulates a lower d excess during the LGM over most high‐latitude regions, consistent with observations. Finally, we use LMDZ‐iso to explore the relationship between precipitation and δ18O in the tropics, and we discuss its paleoclimatic implications. We show that the imprint of uniform temperature changes on tropical δ18O is weak. Large regional changes in δ18O can, however, be associated with dynamical changes of precipitation. Using LMDZ as a test bed for reconstructing past precipitation changes through local δ18O records, we show that past tropical precipitation changes can be well reconstructed qualitatively but not quantitatively. Over continents, nonlocal effects make the local reconstruction even less accurate.
A method for the determination of the hydraulic properties of soil from MODIS surface temperature for use in land‐surface models
Authors: Gutmann Ethan D. , Small Eric E.
Published: June 2010

Soil hydraulic properties (SHPs) play an important role in land‐surface models, but their spatial distribution is poorly known, and it is not feasible to make field measurements of SHPs everywhere they are needed. In addition, the scale SHPs are measured on (10 cm) is substantially smaller than the scale at which land‐surface models are run (>1 km). As a result, land‐surface models need landscape hydraulic properties (LHPs), not SHPs. We present a method for identifying LHPs from MODIS surface temperatures. We calibrated LHPs in the Noah land‐surface model using MODIS surface temperatures in 2005 at 14 sites from the Atmospheric Radiation Measurement Program (ARM) using locally observed forcing data from 2005. We then used observed flux data during this same time period for model verification. Next, we determined LHPs from MODIS surface temperature at five sites using High Resolution Land Data Assimilation forcing data from 2002. We then used these LHPS to run Noah with 2005 ARM forcing data and compared the output to the same observed 2005 fluxes. Fitting LHPs to MODIS data decreases the error in modeled latent heat flux from 98 W/m2 to 67 W/m2. Fitting LHPs to these same latent heat flux measurements decreases the error to 50 W/m2. Therefore, two thirds of the parameter estimation improvement from calibration to in situ flux data can be achieved using remotely sensed surface temperature. These results are insensitive to errors in other parameters. For example, changing albedo by 0.1 changes the saturated conductivity (Ks) by 10% and the van Genuchten “m” parameter by 1%. However, changing minimum canopy resistance by 40 s/m produced a significant but mutually compensating change in both Ks and “m.”
Task-Technology Fit for Mobile Information Systems
Authors: Gebauer Judith , Shaw Michael J , Gribbins Michele L
Published: June 2010

Mobile information technology (IT) holds great promise to support managerial processes; however, clear guidelines of how to design effective mobile Information systems (IS) for use by managers are still lacking. Building on earlier research studies of task-technology fit (TTF) and other areas of IS, this article presents a three-step conceptual model to establish fit between managerial tasks, mobile IT, and the mobile use context, assuming that a good fit positively impacts task performance. We find that use situations characterized by high distraction and poor quality of network connection are particularly challenging for the design of mobile IS, and that the user Interface requires particular attention. Our model contributes to IS research by joining disparate streams of research in an effort to help advance our understanding about the development and utilization of mobile IS. From a practical perspective, we contribute to the success of mobile IS and to the effectiveness of mobile work as It becomes increasingly prevalent in our modern world.
Protein and gene model inference based on statistical modeling in k-partite graphs
Authors: Gerster Sarah , Qeli Ermir , Ahrens Christian H. , Bühlmann Peter
Published: June 2010

One of the major goals of proteomics is the comprehensive and accurate description of a proteome. Shotgun proteomics, the method of choice for the analysis of complex protein mixtures, requires that experimentally observed peptides are mapped back to the proteins they were derived from. This process is also known as protein inference. We present Markovian Inference of Proteins and Gene Models (MIPGEM), a statistical model based on clearly stated assumptions to address the problem of protein and gene model inference for shotgun proteomics data. In particular, we are dealing with dependencies among peptides and proteins using a Markovian assumption on k-partite graphs. We are also addressing the problems of shared peptides and ambiguous proteins by scoring the encoding gene models. Empirical results on two control datasets with synthetic mixtures of proteins and on complex protein samples ofSaccharomyces cerevisiae,Drosophila melanogaster, andArabidopsis thalianasuggest that the results with MIPGEM are competitive with existing tools for protein inference.
Self-organization of the phosphatidylinositol lipids signaling system for random cell migration
Authors: Arai Yoshiyuki , Shibata Tatsuo , Matsuoka Satomi , Sato Masayuki J. , Yanagida Toshio , Ueda Masahiro
Published: June 2010

Phosphatidylinositol (PtdIns) lipids have been identified as key signaling mediators for random cell migration as well as chemoattractant-induced directional migration. However, how the PtdIns lipids are organized spatiotemporally to regulate cellular motility and polarity remains to be clarified. Here, we found that self-organized waves of PtdIns 3,4,5-trisphosphate [PtdIns(3,4,5)P
3
] are generated spontaneously on the membrane of
Dictyostelium
cells in the absence of a chemoattractant. Characteristic oscillatory dynamics within the PtdIns lipids signaling system were determined experimentally by observing the phenotypic variability of PtdIns lipid waves in single cells, which exhibited characteristics of a relaxation oscillator. The enzymes phosphatase and tensin homolog (PTEN) and phosphoinositide-3-kinase (PI3K), which are regulators for PtdIns lipid concentrations along the membrane, were essential for wave generation whereas functional actin cytoskeleton was not. Defects in these enzymes inhibited wave generation as well as actin-based polarization and cell migration. On the basis of these experimental results, we developed a reaction-diffusion model that reproduced the characteristic relaxation oscillation dynamics of the PtdIns lipid system, illustrating that a self-organization mechanism provides the basis for the PtdIns lipids signaling system to generate spontaneous spatiotemporal signals for random cell migration and that molecular noise derived from stochastic fluctuations within the signaling components gives rise to the variability of these spontaneous signals.
Core human mitochondrial transcription apparatus is a regulated two-component system in vitro
Authors: Shutt Timothy E. , Lodeiro Maria F. , Cotney Justin , Cameron Craig E. , Shadel Gerald S.
Published: June 2010

The core human mitochondrial transcription apparatus is currently regarded as an obligate three-component system comprising the bacteriophage T7-related mitochondrial RNA polymerase, the rRNA methyltransferase-related transcription factor, h-mtTFB2, and the high mobility group box transcription/DNA-packaging factor, h-mtTFA/TFAM. Using a faithful recombinant human mitochondrial transcription system fromEscherichia coli, we demonstrate that specific initiation from the mtDNA promoters, LSP and HSP1, only requires mitochondrial RNA polymerase and h-mtTFB2 in vitro. When h-mtTFA is added to these basal components, LSP exhibits a much lower threshold for activation and a larger amplitude response than HSP1. In addition, when LSP and HSP1 are together on the same transcription template, h-mtTFA-independent transcription from HSP1 and h-mtTFA-dependent transcription from both promoters is enhanced and a higher concentration of h-mtTFA is required to stimulate HSP1. Promoter competition experiments revealed that, in addition to LSP competing transcription components away from HSP1, additionalcis-acting signals are involved in these aspects of promoter regulation. Based on these results, we speculate that the human mitochondrial transcription system may have evolved to differentially regulate transcription initiation and transcription-primed mtDNA replication in response to the amount of h-mtTFA associated with nucleoids, which could begin to explain the heterogeneity of nucleoid structure and activity in vivo. Furthermore, this study sheds new light on the evolution of mitochondrial transcription components by showing that the human system is a regulated two-component system in vitro, and thus more akin to that of budding yeast than thought previously.
Direct asymmetric vinylogous Michael addition of cyclic enones to nitroalkenes via dienamine catalysis
Authors: Bencivenni Giorgio , Galzerano Patrizia , Mazzanti Andrea , Bartoli Giuseppe , Melchiorre Paolo
Published: June 2010

In spite of the many catalytic methodologies available for the asymmetric functionalization of carbonyl compounds at their α and β positions, little progress has been achieved in the enantioselective carbon–carbon bond formation γ to a carbonyl group. Here, we show that primary amine catalysis provides an efficient way to address this synthetic issue, promoting vinylogous nucleophilicity upon selective activation of unmodified cyclic α,β-unsaturated ketones. Specifically, we document the development of the unprecedented direct and vinylogous Michael addition of β-substituted cyclohexenone derivatives to nitroalkenes proceeding under dienamine catalysis. Besides enforcing high levels of diastereo- and enantioselectivity, chiral primary amine catalysts derived from natural cinchona alkaloids ensure complete γ-site selectivity: The resulting, highly functionalized vinylogous Michael adducts, having two stereocenters at the γ and δ positions, are synthesized with very high fidelity. Finally, we describe the extension of the dienamine catalysis-induced vinylogous nucleophilicity to the asymmetric γ-amination of cyclohexene carbaldehyde.
Desulfovibrio magneticus
RS-1 contains an iron- and phosphorus-rich organelle distinct from its bullet-shaped magnetosomes
Authors: Byrne Meghan E. , Ball David A. , Guerquin-Kern Jean-Luc , Rouiller Isabelle , Wu Ting-Di , Downing Kenneth H. , Vali Hojatollah , Komeili Arash
Published: June 2010

Intracellular magnetite crystal formation by magnetotactic bacteria has emerged as a powerful model for investigating the cellular and molecular mechanisms of biomineralization, a process common to all branches of life. Although magnetotactic bacteria are phylogenetically diverse and their crystals morphologically diverse, studies to date have focused on a few, closely related species with similar crystal habits. Here, we investigate the process of magnetite biomineralization in
Desulfovibrio magneticus
sp. RS-1, the only reported species of cultured magnetotactic bacteria that is outside of the α-Proteobacteria and that forms bullet-shaped crystals. Using a variety of high-resolution imaging and analytical tools, we show that RS-1 cells form amorphous, noncrystalline granules containing iron and phosphorus before forming magnetite crystals. Using NanoSIMS (dynamic secondary ion mass spectroscopy), we show that the iron-phosphorus granules and the magnetite crystals are likely formed through separate cellular processes. Analysis of the cellular ultrastructure of RS-1 using cryo-ultramicrotomy, cryo-electron tomography, and tomography of ultrathin sections reveals that the magnetite crystals are not surrounded by membranes but that the iron-phosphorus granules are surrounded by membranous compartments. The varied cellular paths for the formation of these two minerals lead us to suggest that the iron-phosphorus granules constitute a distinct bacterial organelle.
Genome sequences of the human body louse and its primary endosymbiont provide insights into the permanent parasitic lifestyle
Authors: Kirkness Ewen F. , Haas Brian J. , Sun Weilin , Braig Henk R. , Perotti M. Alejandra , Clark John M. , Lee Si Hyeock , Robertson Hugh M. , Kennedy Ryan C. , Elhaik Eran , Gerlach Daniel , Kriventseva Evgenia V. , Elsik Christine G. , Graur Dan , Hill Catherine A. , Veenstra Jan A. , Walenz Brian , Tubío José Manuel C. , Ribeiro José M. C. , Rozas Julio , Johnston J. Spencer , Reese Justin T. , Popadic Aleksandar , Tojo Marta , Raoult Didier , Reed David L. , Tomoyasu Yoshinori , Kraus Emily , Mittapalli Omprakash , Margam Venu M. , Li Hong-Mei , Meyer Jason M. , Johnson Reed M. , Romero-Severson Jeanne , VanZee Janice Pagel , Alvarez-Ponce David , Vieira Filipe G. , Aguadé Montserrat , Guirao-Rico Sara , Anzola Juan M. , Yoon Kyong S. , Strycharz Joseph P. , Unger Maria F. , Christley Scott , Lobo Neil F. , Seufferheld Manfredo J. , Wang NaiKuan , Dasch Gregory A. , Struchiner Claudio J. , Madey Greg , Hannick Linda I. , Bidwell Shelby , Joardar Vinita , Caler Elisabet , Shao Renfu , Barker Stephen C. , Cameron Stephen , Bruggner Robert V. , Regier Allison , Johnson Justin , Viswanathan Lakshmi , Utterback Terry R. , Sutton Granger G. , Lawson Daniel , Waterhouse Robert M. , Venter J. Craig , Strausberg Robert L. , Berenbaum May R. , Collins Frank H. , Zdobnov Evgeny M. , Pittendrigh Barry R.
Published: June 2010

As an obligatory parasite of humans, the body louse (
Pediculus humanus humanus
) is an important vector for human diseases, including epidemic typhus, relapsing fever, and trench fever. Here, we present genome sequences of the body louse and its primary bacterial endosymbiont
Candidatus
Riesia pediculicola. The body louse has the smallest known insect genome, spanning 108 Mb. Despite its status as an obligate parasite, it retains a remarkably complete basal insect repertoire of 10,773 protein-coding genes and 57 microRNAs. Representing hemimetabolous insects, the genome of the body louse thus provides a reference for studies of holometabolous insects. Compared with other insect genomes, the body louse genome contains significantly fewer genes associated with environmental sensing and response, including odorant and gustatory receptors and detoxifying enzymes. The unique architecture of the 18 minicircular mitochondrial chromosomes of the body louse may be linked to the loss of the gene encoding the mitochondrial single-stranded DNA binding protein. The genome of the obligatory louse endosymbiont
Candidatus
Riesia pediculicola encodes less than 600 genes on a short, linear chromosome and a circular plasmid. The plasmid harbors a unique arrangement of genes required for the synthesis of pantothenate, an essential vitamin deficient in the louse diet. The human body louse, its primary endosymbiont, and the bacterial pathogens that it vectors all possess genomes reduced in size compared with their free-living close relatives. Thus, the body louse genome project offers unique information and tools to use in advancing understanding of coevolution among vectors, symbionts, and pathogens.
Elucidation of the active conformation of cinchona alkaloid catalyst and chemical mechanism of alcoholysis of meso anhydrides
Authors: Li Hongming , Liu Xiaofeng , Wu Fanghui , Tang Liang , Deng Li
Published: June 2010

Complementary to enantioselective transformations of planar functionalities, catalytic desymmetrization of
meso
compounds is another fundamentally important strategy for asymmetric synthesis. However, experimentally established stereochemical models on how a chiral catalyst discriminates between two enantiotopic functional groups in the desymmetrization of a
meso
substrate are particularly lacking. This article describes our endeavor to elucidate the chemical mechanism and characterization of the active conformation of the cinchona alkaloid-derived catalyst for a desymmetrization of
meso
cyclic anhydrides via asymmetric alcoholysis. First, our kinetic studies indicate that the cinchona alkaloid-catalyzed alcoholysis proceeds by a general base catalysis mechanism. Furthermore, the active conformer of the cinchona alkaloid-derived catalyst DHQD-PHN was clarified by catalyst conformation studies with a designed, rigid cinchona alkaloid derivative as a probe. These key mechanistic insights enabled us to construct a stereochemical model to rationalize how DHQD-PHN differentiates the two enantiotopic carbonyl groups in the transition state of the asymmetric alcoholysis of
meso
cyclic anhydrides. This model not only is consistent with the sense of asymmetric induction of the asymmetric alcoholysis but also provides a rationale on how the catalyst tolerates a broad range of cyclic anhydrides. These mechanistic insights further guided us to develop a novel practical catalyst for the enantioselective alcoholysis of
meso
cyclic anhydrides.