bluuebunny/crossref_metadata_2025 huggingface dataset:
Balancing Effectiveness and Fairness in the Redesign of the Climate Change Regime
Authors: VIÑUALES JORGE E.
Published: February 2011

Since its modern inception in the 1960s, international environmental law (IEL) has faced three main challenges: (i) justifying the need for an international regulation of environmental issues (legitimacy); (ii) finding mechanisms to ensure compliance with IEL (effectiveness); and (iii) distributing equitably the benefits and burden of environmental protection (fairness). While it is nowadays possible to say that the legitimacy of IEL is no longer in question, the need to respond to challenges (ii) and (iii) has never been more pressing. This is particularly the case in the context of the redesign of the climate change regime (CCR), as the responses to (ii) and (iii) may conflict with each other. Industrialized countries who historically contributed the most to the artificial increase in greenhouse gases (GHGs) in the atmosphere have been matched, and even surpassed, in their level of GHG emissions by countries such as China, India, or Brazil, who are now being pressed to undertake real emissions-reduction commitments. Historically, however, none of these latter benefited from the emission laxity characterizing the nineteenth century and most of the twentieth century to further their development. While imposing specific emissions-reduction commitments on them would seem unfair, such commitments are nevertheless critical for the effectiveness of the regime both directly and indirectly (as without such commitments, industrialized countries may be reluctant to join or uphold a regime). The purpose of this article is to spell out in an orderly analytical manner the types of issue that must be addressed in seeking a balanced solution. This type of analysis can be conducted from several perspectives. The most directly relevant disciplines to deal with fairness considerations are admittedly ethics and political philosophy, and there is indeed a growing literature on climate fairness. Although this literature is briefly surveyed, the article focuses on the fairness dimensions of the existing legal arrangements or those currently being negotiated. There is a considerable gap between the theoretical approaches to climate fairness and the manner in which considerations of fairness operate in practice. This gap is mainly due to the need to account for political considerations or, in other terms, to balance fairness with political effectiveness. When such considerations are taken into account, the picture that emerges is quite different. The CCR is not built upon a single approach to fairness. Rather, fairness considerations are integrated through a patchwork of criteria used to distribute different objects (burden of emission reductions, emission rights, contribution to financial and technological assistance, and access to such assistance) among different actors situated at different levels.
Distribution, habitat use, and implications for the conservation of the globally threatened Azure-rumped TanagerTangara cabanisiin Guatemala
Authors: EISERMANN KNUT , ARBEITER SUSANNE , LÓPEZ GERARDO , AVENDAÑO CLAUDIA , DE LEÓN LUX JOSUÉ
Published: February 2011

The Azure-rumped TanagerTangara cabanisiis a globally threatened species restricted to the Pacific slope mountains of western Guatemala and Chiapas, Mexico. We studied the habitat use of this tanager on the southern slope of Atitlán volcano, department Suchitepéquez, Guatemala, applying distance sampling along transects in humid broadleaf forest and coffee plantations. The tanager was recorded in both habitat types, but encounter rates were significantly greater in broadleaf forest. The estimated density of tanagers in forest at 1,400–1,900 m was 33–93 birds km−2. Tanagers were recorded mainly in the upper vegetation strata of forest and shade coffee plantations. In coffee plantations tanagers used mainly tall solitary trees or the canopy of shade trees, which were dominated byIngaspp. The number of observations of feeding tanagers inFicus aurea(Moraceae) indicated a high importance of this food source. The density ofF. aureatrees and the encounter rate of tanagers were positively correlated. From 1987 to 2009 tanagers have been recorded at nine topographic units and a total of 16 sites in Guatemala, in the departments of San Marcos, Quetzaltenango, Sololá, Suchitepéquez, and Chimaltenango. We analysed the available habitat for tanagers in the potential area of distribution (1,170 km2), ranging from 900 to 1,900 m altitude and from the Mexican border in the West to the municipality of Pochuta in the East. Broadleaf forest covers 250 km2or 21% of the potential area of distribution, and coffee plantations cover 800 km2or 68%. Assuming that population density in prime habitat throughout the potential distribution range is similar to our study area at Atitlán volcano, total tanager population in Guatemala is estimated to be 8,250–23,250 birds. Our findings support the maintenance of the IUCN Red List status of Endangered EN B1a+b(ii,iii,v). To enhance the available habitat for Azure-rumped Tanager, we propose alterations in the shade management of coffee plantations, supported by incentives and certification programmes.
Report from The International Society for Nomenclature of Paediatric and Congenital Heart Disease: cardiovascular catheterisation for congenital and paediatric cardiac disease (Part 1 – Procedural nomenclature)
Authors: Bergersen Lisa , Everett Allen Dale , Giroud Jorge Manuel , Martin Gerard R. , Franklin Rodney Cyril George , Béland Marie Josée , Krogmann Otto Nils , Aiello Vera Demarchi , Colan Steven D. , Elliott Martin J. , Gaynor J. William , Kurosawa Hiromi , Maruszewski Bohdan , Stellin Giovanni , Tchervenkov Christo I. , Walters Henry Lane , Weinberg Paul , Jacobs Jeffrey Phillip
Published: February 2011

Interventional cardiology for paediatric and congenital cardiac disease is a relatively young and rapidly evolving field. As the profession begins to establish multi-institutional databases, a universal system of nomenclature is necessary for the field of interventional cardiology for paediatric and congenital cardiac disease. The purpose of this paper is to present the results of the efforts of The International Society for Nomenclature of Paediatric and Congenital Heart Disease to establish a system of nomenclature for cardiovascular catheterisation for congenital and paediatric cardiac disease, focusing both on procedural nomenclature and on the nomenclature of complications associated with interventional cardiology. This system of nomenclature for cardiovascular catheterisation for congenital and paediatric cardiac disease is a component of The International Paediatric and Congenital Cardiac Code. This manuscript is the first part of a two-part series. Part 1 will cover the procedural nomenclature associated with interventional cardiology as treatment for paediatric and congenital cardiac disease. This procedural nomenclature of The International Paediatric and Congenital Cardiac Code will be used in the IMPACT Registry™ (IMproving Pediatric and Adult Congenital Treatment) of the National Cardiovascular Data Registry®of The American College of Cardiology. Part 2 will cover the nomenclature of complications associated with interventional cardiology as treatment for paediatric and congenital cardiac disease.
Report from The International Society for Nomenclature of Paediatric and Congenital Heart Disease: cardiovascular catheterisation for congenital and paediatric cardiac disease (Part 2 – Nomenclature of complications associated with interventional cardiology)
Authors: Bergersen Lisa , Giroud Jorge Manuel , Jacobs Jeffrey Phillip , Franklin Rodney Cyril George , Béland Marie Josée , Krogmann Otto Nils , Aiello Vera Demarchi , Colan Steven D. , Elliott Martin J. , Gaynor J. William , Kurosawa Hiromi , Maruszewski Bohdan , Stellin Giovanni , Tchervenkov Christo I. , Walters Henry Lane , Weinberg Paul , Everett Allen Dale
Published: February 2011

Interventional cardiology for paediatric and congenital cardiac disease is a relatively young and rapidly evolving field. As the profession begins to establish multi-institutional databases, a universal system of nomenclature is necessary for the field of interventional cardiology for paediatric and congenital cardiac disease. The purpose of this paper is to present the results of the efforts of The International Society for Nomenclature of Paediatric and Congenital Heart Disease to establish a system of nomenclature for cardiovascular catheterisation for congenital and paediatric cardiac disease, focusing both on procedural nomenclature and the nomenclature of complications associated with interventional cardiology. This system of nomenclature for cardiovascular catheterisation for congenital and paediatric cardiac disease is a component of The International Paediatric and Congenital Cardiac Code. This manuscript is the second part of the two-part series. Part 1 covered the procedural nomenclature associated with interventional cardiology as treatment for paediatric and congenital cardiac disease. Part 2 will cover the nomenclature of complications associated with interventional cardiology as treatment for paediatric and congenital cardiac disease.
Shared environments: a multilevel analysis of community context and child nutritional status in Bangladesh
Authors: Corsi Daniel J , Chow Clara K , Lear Scott A , Rahman M Omar , Subramanian SV , Teo Koon K
Published: February 2011

Objective

The goal of the present study was to examine the influence of community environment on the nutritional status (weight-for-age and height-for-age) of children (aged 0–59 months) in Bangladesh. In addition, we tested the association between specific characteristics of community environments and child nutritional status.

Design

Cross-sectional survey.

Setting

The data are from the nationally representative 2004 Bangladesh Demographic and Health Survey.

Subjects

Respondents were ever-married women (aged 15–49 years) and their children (n5731), residing in 361 communities. Child nutritional outcomes are physical measurements of weight-for-age and height-for-age insdunits. We considered the following attributes of community environments potentially related to child nutrition: (i) community water and sanitation infrastructure; (ii) availability of community health and education services; (iii) community employment and social participation; and (iv) education level of the community.

Results

Multilevel regression analysis showed that the spatial distribution of maternal and child covariates did not entirely explain the between-community variation in child nutritional status. The education level of the community emerged as the strongest community-level predictor of child height-for-age (highestv. lowest tertile,β= 0·18 (se0·07)) and weight-for-age (highestv. lowest tertile,β= 0·21 (se0·06)). In the height-for-age model, community employment and social participation also emerged as being statistically significant (highestv. lowest tertile,β= 0·13 (se= 0·06)).

Conclusions

The community environment influences child nutrition in Bangladesh, and maternal- and child-level covariates may fail to capture the entire influence of communities. Interventions to reduce child undernutrition in developing countries should take into consideration the wider community context.
Upper Ordovician (Sandbian–Katian) graptolite and conodont zonation in the Yangtze region, China
Authors: Xu Chen , Bergström Stig M. , Yuandong Zhang , Goldman Dan , Qing Chen
Published: February 2011

The graptolite and conodont biostratigraphy of the latest Darriwilian, Sandbian and early and middle Katian succession on the Yangtze Platform is reassessed based on numerous new fossil collections and previously published data. At least at some localities, the lowermost Miaopo Formation is of pre-Nemagraptus gracilis Zone age (uppermost Pygodus serra and lowermost P. anserinus conodont zones). The rest of this formation (except for the uppermost part, which lacks diagnostic graptolites) has a diverse graptolite fauna of the N. gracilis Zone. The uppermost part of the Miaopo Formation contains few biostratigraphically diagnostic graptolites but the occurrence of conodonts of the Baltoniodus alobatus Subzone of the Amorphognathus tvaerensis Zone suggests equivalence with part of the Climacograptus bicornis graptolite Zone. The conodont succession of the Datianba Formation is virtually identical with that of the Miaopo Formation, confirming that these units are coeval. The lowermost part of the overlying non-graptolitic Pagoda Formation represents the upper A. tvaerensis Zone, and its upper part represents the A. superbus Zone. The occurrence of Dicellograptus elegans in the overlying Chientsaokou Formation (equivalent to the Linhsiang Formation in Yangtze Gorges region) suggests equivalence with the Pleurograptus linearis Zone in Scotland, which is consistent with the relatively non-diagnostic conodont fauna in these Chinese units. The biostratigraphic data are in good agreement with the δ13C chemostratigraphy and permit the establishment of precise correlations with the Baltoscandic and North American successions.
Late Ordovician trilobites from the Karagach Formation of the western Tarbagatai Range, Kazakhstan
Authors: Ghobadi Pour Mansoureh , McCobb Lucy M. E. , Owens Robert M. , Popov Leonid E.
Published: February 2011

Two trilobite faunas of late Ordovician (Sandbian and Katian) age are described from the siliciclastic Karagach Formation, western Tarbagatai Range, eastern Kazakhstan. They comprise 15 families and 24 genera and include the new taxa Agerina acutilimbata sp. nov., Birmanites akchiensis sp. nov., Dulanaspis karagachensis sp. nov. and Kimakaspis kovalevskyi gen. et sp. nov. Most of the Karagach Formation yields graptolites characteristic of the Diplograptus foliaceus [multidens] Biozone, which are associated with the older trilobite fauna; the uppermost part, which is the source of the younger trilobite fauna, contains Orthograptus quadrimucronatus and Dicranograptus hians which suggest a younger age, equating with the lowermost Ensigraptus caudatus Biozone, and the base of the Katian Stage. Most of the trilobite genera in both faunas have a wide geographical distribution in the late Ordovician, although Dulanaspis and Sinocybele are characteristic of low latitude eastern peri-Gondwanan faunas.
Dissociations Between ABA-, ABC-, and AAB-Renewal of Pavlovian Modulation in Human Sequential Feature Positive Discrimination Learning
Authors: Fonteyne Riet , Baeyens Frank
Published: February 2011

Using a conditioned suppression preparation, we investigated extinction and aba-, abc-, and aab-renewal of Pavlovian modulation in human sequential Feature Positive (FP) discrimination learning, X → A+/A−. Extinction treatment was administered in the acquisition context a (aaa- and aab-groups) or in a new context b (aba- and abc-groups) and comprised X → A− extinction trials. Discriminative X → A/A responding was lost in all groups when tested in the extinction context. In the aba-group, the discriminative X → A/A responding totally recovered when retested in the acquisition context a. For the aaa-, the aab-, and the abc-group, discriminative X → A/A responding did not reappear when tested for renewal in, respectively, contexts a, b, and c. The demonstration of aba-renewal of extinguished modulation, but not abc- and aab-renewal, suggests that extinction in a context different from the acquisition context and a return to the original acquisition context might both be critical for renewal of Pavlovian modulation in human FP-discrimination learning.
Signal Detection and Threshold Models of Source Memory
Authors: Schütz Julia , Bröder Arndt
Published: February 2011

Recently, several authors claimed that the curvilinear shape of rating-based source memory receiver operating characteristics (ROCs) refutes threshold models. However, rating-based ROCs are not diagnostic to disprove threshold models. Furthermore, source memory ROC-analyses ignore influences of other processes like old-new-detection and old-new-response-tendencies, so direct estimation of parameters is preferable. Five source monitoring experiments with different response bias manipulations and materials were conducted. We fitted the Two High Threshold Multinomial Model of Source Monitoring by Bayen, Murnane, and Erdfelder (1996) and the Multivariate Signal Detection Model for Selection by DeCarlo (2003) . We also included rating-based ROCs. The results suggest that both models are at least equally valid as measurement tools which capture bias processes in the corresponding parameters, and they can perhaps be integrated theoretically.
Evidence of Vocal and Manual Event Files in Auditory Negative Priming
Authors: Mayr Susanne , Möller Malte , Buchner Axel
Published: February 2011

Negative priming with auditory as well as with visual stimuli has been shown to involve the retrieval of prime response information as evidenced by an increase of prime response errors to the probes of ignored repetition trials compared to control trials. We investigated whether prime response retrieval processes were also present for response modalities other than manual responding. In an auditory four alternative forced choice task participants either vocally or manually identified a target sound while ignoring a distractor sound. Negative priming was of equal size in both response modalities. What is more, for both response modalities, there was evidence of increased prime response errors in ignored repetition trials compared to control trials. The findings suggest that retrieval of event files of the prime episode including prime response information is a general mechanism underlying the negative priming phenomenon irrespective of stimulus or response modality.
Retrieval-Induced Forgetting of Performed and Observed Bizarre and Familiar Actions
Authors: Sharman Stefanie J.
Published: February 2011

To investigate whether people show retrieval-induced forgetting (RIF) for bizarre and familiar actions that they performed or observed, three experiments were conducted. In Experiment 1, participants performed bizarre and familiar actions with different objects during learning (e.g., pencil: balance the pencil across the cup, sharpen the pencil). They repeatedly performed a set of the bizarre or familiar actions during retrieval practice. After a distracter task, participants’ cued recall was tested. Participants showed RIF for both bizarre and familiar actions. In Experiment 2, half of the participants performed the bizarre and familiar actions themselves; the other half observed the experimenter performing the actions. Replicating the results of Experiment 1, participants who performed the actions showed RIF for bizarre and familiar actions. In contrast, participants who observed the actions did not show RIF for either action type. Experiment 3 examined whether this lack of RIF for observed actions occurred due to a lack of active recall during retrieval practice; it did. Overall, the three experiments demonstrated RIF for both bizarre and familiar performed and observed actions. A distinctiveness account of the results is provided.
Learning Conversation and Shared Network Leadership
Authors: Weibler Jürgen , Rohn-Endres Sigrid
Published: February 2011

This paper develops an understanding of how shared leadership emerges in social network interactions. On the basis of a qualitative research design (grounded theory methodology – GTM) our study in two interorganizational networks offers insights into the interplay between structures, individuals, and the collective for the emergence of shared network leadership (SNL). The network-specific Gestalt of SNL appears as a pattern of collective and individual leadership activities unified under the roof of a highly developed learning conversation. More importantly, our findings support the idea that individual network leadership would not emerge without embeddedness in certain high-quality collective processes of relating and dialogue. Both theoretical and practical implications of this original network leadership perspective are discussed.
Shared Leadership in Teams
Authors: Engel Small Erika , Rentsch Joan R.
Published: February 2011

Shared leadership is an emergent team process defined by the distribution of leadership functions among multiple team members. Past empirical research on shared leadership has operationalized it as the overall quantity of leadership in the team, neglecting the essence of the conceptual definition – the distribution of leadership. In order to align the conceptual definition with an operational one, we examined shared leadership as network centralization using social network analysis. Using this operational definition, shared leadership was positively related to team performance. Additionally, longitudinal analyses revealed that shared leadership increased over time and was differentially related to antecedents of trust and team collectivism.
Measuring and Modeling Shared Leadership
Authors: Gockel Christine , Werth Lioba
Published: February 2011

In this article, we provide an overview of current measures of shared leadership. Our aim is to help researchers choose the appropriate measure and give them advice on the statistical analysis of shared leadership measures. We first present traditional approaches, namely two questionnaires assessing shared leadership behaviors displayed by a team. We then describe social network indexes showing how leadership influence is distributed in a team and the coefficient of variation showing the relative dispersion of team members’ leadership influence. Finally, we present a new idea for modeling mutual influence processes in teams, the actor-partner interdependence model (APIM, Kenny, Kashy, & Cook, 2006). It can depict how each team member’s outcomes are affected by own and other team members’ leadership behaviors. For all approaches, we point out requirements, advantages, and disadvantages.
Mechanisms of mass and heat transport during Barrovian metamorphism: A discussion based on field evidence from the Central Alps (Switzerland/northern Italy)
Authors: Berger Alfons , Schmid Stefan M. , Engi Martin , Bousquet Romain , Wiederkehr Michael
Published: February 2011

Tectonic and metamorphic data for the Central Alps (Switzerland/Italy) are used to discuss this classic example of a Barrovian metamorphic terrain, notably the evolution of its thermal structure in space and time. Available P‐T‐t data indicate variable contributions of advective and conductive heat transport during collision and subsequent cooling and exhumation. Some areas experienced a prolonged period of partial melting while other areas, at the same time, show but moderate heating. The Barrow‐type metamorphic field gradient observed in the final orogen is the result of two distinct tectonic processes, with their related advective and conductive heat transport processes. The two tectonic processes are (1) accretion of material within a subduction channel related to decompression and emplacement of high‐pressure units in the middle crust and (2) wedging and related nappe formation in the continental lower plate. The second process postdates the first one. Wedging and underthrusting of continental lower plate material produces heat input into lower crustal levels, and this process is responsible for predominantly conductive heat transport in the overlying units. The interacting processes lead to different maximum temperatures at different times, producing the final Barrovian metamorphic field gradient. The south experienced rapid cooling, whereas the north shows moderate cooling rates. This discrepancy principally reflects differences in the temperature distribution in the deeper crust prior to cooling. Differences in the local thermal gradient that prevailed before the cooling also determined the relationships between cooling rate and exhumation rate in the different areas.
Hyporheic flow path response to hydraulic jumps at river steps: Flume and hydrodynamic models
Authors: Endreny T. , Lautz L. , Siegel D. I.
Published: February 2011

The conceptual model of hyporheic exchange below river steps may oversimplify exchange flow paths if it depicts a uniform pattern of downstream‐directed upwelling. This research used nonmobile, porous bed flume experiments and hydrodynamic simulation (CFD) to characterize hyporheic flow paths below a river step with a hydraulic jump. Bed slope was 1%, step height was 4 cm, downstream flow depth was 4 cm, substrate was 1 cm median diameter gravel, and hydraulic jump length was 25 cm in the flume and CFD experiments. With the hydraulic jump, flow paths changed to include downwelling beneath the water plunging into the pool and upstream‐directed upwelling at the base of the step and beneath the length of jump. Failure to represent the influence of static and dynamic pressures associated with hydraulic jumps leads to erroneous prediction of subsurface flow paths in 75% of the streambed beneath the jump. A refined conceptual model for hyporheic flow paths below a step with a hydraulic jump includes reversed hyporheic circulation cells, in which downwelling water moves upstream and then upwells, and flow reversals, in which the larger flow net of downstream‐directed upwelling encounters a nested flow path of upstream‐directed upwelling. Heterogeneity in hyporheic flow paths at hydraulic jumps has the potential to explain field‐observed mosaics in streambed redox patterns and expand structure‐function relationships used in river management and restoration.
The effect of solar activity on the Doppler and multipath spread of HF signals received over paths oriented along the midlatitude trough
Authors: Stocker A. J. , Warrington E. M.
Published: February 2011

Measurements of the Doppler and delay spread associated with HF signals propagating along an oblique (1440 km) path tangential to the midlatitude ionospheric trough are presented for sunspot maximum and minimum. During the day, Doppler spread is independent of solar activity, but for winter and equinoctial nights, it is very much higher at sunspot maximum. The delay spread is also generally higher at sunspot maximum for all seasons and times of day. For sunspot minimum, measurements from a second, longer path (1800 km) are also presented. The observed Doppler and delay spreads are similar for both paths. Finally, a novel method of more accurately deriving the delay spread defined by the International Telecommunication Union (i.e., the largest delay spread including all modes that have a peak power within a user‐defined threshold of that of the strongest mode) from Voice of America coverage analysis program (VOACAP) predictions is presented. For the first time, the predicted values are compared with the measured delay spreads and, while there is generally good agreement at sunspot minimum, the agreement at sunspot maximum tends to be poor because the behavior of the high‐order ionospheric modes (e.g., 3F2) is not well predicted by VOACAP.
Evaluation of the orbit altitude electron density estimation and its effect on the Abel inversion from radio occultation measurements
Authors: Yue Xinan , Schreiner William S. , Rocken Christian , Kuo Ying‐Hwa
Published: February 2011

In this paper, the observations from CHAMP radio occultation (RO) and Planar Langmuir Probe (PLP) during 2002–2008 and Constellation Observing System for Meteorology Ionosphere and Climate (COSMIC) observations during 2007.090–2007.120 are used to evaluate the orbit altitude electron density estimation and its effect on the Abel inversion from RO measurements. Comparison between PLP observed and RO estimated orbit electron density on board CHAMP shows that RO estimation tends to overestimate the true orbit electron density by 10% averagely. The average relative deviation is ∼20% and decreases slightly with the increase of the ionospheric peak height and the satellite orbit. It is larger at nighttime than daytime and peaks around sunrise time. Simulations based on COSMIC observations using NeQuick model indicate that the solar activity and the satellite orbit altitude variations will not influence the ratio of the successfully retrieved electron density profiles to the observed occultation events and the relative Abel inversion error of the electron density as well. Different orbit electron density derivation methods, including estimation by the RO total electron content, given by an independent on orbit observation, and assumed to be equal to the topmost point, will have no essential influence on the Abel retrieved electron density. Adding an on orbit observation even has a negative effect on the Abel retrieved electron density around the orbit altitude, which is contrary to our imagination.
Effects of watershed land use and geomorphology on stream low flows during severe drought conditions in the southern Blue Ridge Mountains, Georgia and North Carolina, United States
Authors: Price Katie , Jackson C. Rhett , Parker Albert J. , Reitan Trond , Dowd John , Cyterski Mike
Published: February 2011

Land use and physiographic variability influence stream low flows, yet their interactions and relative influence remain unresolved. Our objective was to assess the influence of land use and watershed geomorphic characteristics on low‐flow variability in the southern Blue Ridge Mountains of North Carolina and Georgia. Ten minute interval discharge data for 35 streams (in watersheds from 3 to 146 km2) were measured for two late summer low‐flow seasons, coinciding with a severe drought period in the southeastern United States. Three low‐flow metrics were calculated (1 and 7 day minimum flows and 1st percentile flow) for each low‐flow season (5 August to 12 November 2007 and 1 August to 12 November 2008). A comprehensive suite of watershed characteristics, including factors of topography, channel network morphometry, soils, land use, and precipitation were used in multiple regression analysis of low‐flow variability among the 35 watersheds. Additionally, low flows in groups of lower‐ and higher‐forest cover watersheds were compared. Drainage density, areal coverage of colluvium, topographic variability (as slope standard deviation), and percent of the channel network as first order stream emerged as the most important variables for explaining low‐flow variability. Watershed forest cover demonstrated a consistent, significant positive relationship with low flows, despite the higher evapotranspiration rates associated with forest compared with other land covers and despite the relatively small range of disturbance in this study area. This highlights the importance of infiltration and recharge under undisturbed land cover in sustaining low flows, and it bears noteworthy implications for environmental flows and water resource sustainability.
Determinants of laminin polymerization revealed by the structure of the α5 chain amino‐terminal region
Authors: Hussain Sadaf‐Ahmahni , Carafoli Federico , Hohenester Erhard
Published: February 2011

The polymerization of laminin into a cell‐associated network—a key step in basement membrane assembly—is mediated by the laminin amino‐terminal (LN) domains at the tips of the three short arms of the laminin αβγ‐heterotrimer. The crystal structure of a laminin α5LN–LE1–2 fragment shows that the LN domain is a β‐jelly roll with several elaborate insertions that is attached like a flower head to the stalk‐like laminin‐type epidermal growth factor‐like tandem. A surface loop that is strictly conserved in the LN domains of all α‐short arms is required for stable ternary association with the β‐ and γ‐short arms in the laminin network.
Bio-inspired Materials and Sensing Systems
Authors: Biggins Peter D E , Kusterbeck Anne , Hiltz John A
Published: February 2011

Can scientists and engineers replicate Nature and develop systems that operate in extreme environments? Bio-inspiration is an established concept which is developing to meet the needs of the many challenges we face particularly in defence and security. This book explores the potential of bio-inspired materials and sensing systems together with examples of how they are being implemented. It is not an exhaustive study of the subject but provides an overview of how bio-inspired or -derived approaches can be used to enhance components, systems and systems of systems for defence and security applications. Readers will gain an awareness of the complexity and versatility of bio-inspired components as well as an understanding of how these technologies can be applied in a variety of operational scenarios. Consideration is given to using a conceptual model that can be deployed in distributed or autonomous operations. Using this model, bio-inspiration with behavioural science plays a major role in identification, movement, searching strategies and pattern recognition for chemical and biological detection. Examples focus on both learning new things from nature that have application to the defence and security areas and adapting known discoveries for practical use by these communities. This graduate level monograph provides an increased awareness of the need for more sophisticated, networked sensors and systems in the defence and security communities and will be of interest to both specialists in this area and science and technology generalists.
The C-terminal domain of the neutral amino acid transporter SNAT2 regulates transport activity through voltage-dependent processes
Authors: Zhang Zhou , Zander Catherine B. , Grewer Christof
Published: February 2011

SNAT (sodium-coupled neutral amino acid transporter) 2 belongs to the SLC38 (solute carrier 38) family of solute transporters. Transport of one amino acid molecule into the cell is driven by the co-transport of one Na+ ion. The functional significance of the C-terminus of SNAT2, which is predicted to be located in the extracellular space, is currently unknown. In the present paper, we removed 13 amino acid residues from the SNAT2 C-terminus and studied the effect of this deletion on transporter function. The truncation abolished amino acid transport currents at negative membrane potentials (<0 mV), as well as substrate uptake. However, transport currents were observed at positive membrane potentials demonstrating that transport was accelerated while the driving force decreased. Membrane expression levels were normal in the truncated transporter. SNAT2Del C-ter (13 residues deleted from the C-terminus) showed 3-fold higher apparent affinity for alanine, and 2-fold higher Na+ affinity compared with wild-type SNAT2, suggesting that the C-terminus is not required for high-affinity substrate and Na+ interaction with SNAT2. The pH sensitivity of amino acid transport was retained partially after the truncation. In contrast with the truncation after TM (transmembrane domain) 11, the deletion of TM11 resulted in an inactive transporter, most probably due to a defect in cell surface expression. Taken together, the results demonstrate that the C-terminal domain of SNAT2 is an important voltage regulator that is required for a normal amino acid translocation process at physiological membrane potentials. However, the C-terminus appears not to be involved in the regulation of membrane expression.
Functional characterization of human Polycomb-like 3 isoforms identifies them as components of distinct EZH2 protein complexes
Authors: Boulay Gaylor , Rosnoblet Claire , Guérardel Cateline , Angrand Pierre-Olivier , Leprince Dominique
Published: February 2011

PcG (Polycomb group) proteins are conserved transcriptional repressors essential to regulate cell fate and to maintain epigenetic cellular memory. They work in concert through two main families of chromatin-modifying complexes, PRC1 (Polycomb repressive complex 1) and PRC2–4. In Drosophila, PRC2 contains the H3K27 histone methyltransferase E(Z) whose trimethylation activity towards PcG target genes is stimulated by PCL (Polycomb-like). In the present study, we have examined hPCL3, one of its three human paralogues. Through alternative splicing, hPCL3 encodes a long isoform, hPCL3L, containing an N-terminal TUDOR domain and two PHDs (plant homeodomains) and a smaller isoform, hPCL3S, lacking the second PHD finger (PHD2). By quantitative reverse transcription–PCR analyses, we showed that both isoforms are widely co-expressed at high levels in medulloblastoma. By co-immunoprecipitation analyses, we demonstrated that both isoforms interact with EZH2 through their common TUDOR domain. However, the hPCL3L-specific PHD2 domain, which is better conserved than PHD1 in the PCL family, is also involved in this interaction and implicated in the self-association of hPCL3L. Finally, we have demonstrated that both hPCL3 isoforms are physically associated with EZH2, but in different complexes. Our results provide the first evidence that the two hPCL3 isoforms belong to different complexes and raise important questions about their relative functions, particularly in tumorigenesis.
Two dileucine motifs mediate late endosomal/lysosomal targeting of transmembrane protein 192 (TMEM192) and a C-terminal cysteine residue is responsible for disulfide bond formation in TMEM192 homodimers
Authors: Behnke Jörg , Eskelinen Eeva-Liisa , Saftig Paul , Schröder Bernd
Published: February 2011

TMEM192 (transmembrane protein 192) is a novel constituent of late endosomal/lysosomal membranes with four potential transmembrane segments and an unknown function that was initially discovered by organellar proteomics. Subsequently, localization in late endosomes/lysosomes has been confirmed for overexpressed and endogenous TMEM192, and homodimers of TMEM192 linked by disulfide bonds have been reported. In the present study the molecular determinants of TMEM192 mediating its transport to late endosomes/lysosomes were analysed by using CD4 chimaeric constructs and mutagenesis of potential targeting motifs in TMEM192. Two directly adjacent N-terminally located dileucine motifs of the DXXLL-type were found to be critical for transport of TMEM192 to late endosomes/lysosomes. Whereas disruption of both dileucine motifs resulted in mistargeting of TMEM192 to the plasma membrane, each of the two motifs was sufficient to ensure correct targeting of TMEM192. In order to study disulfide bond formation, mutagenesis of cysteine residues was performed. Mutation of Cys266 abolished disulfide bridge formation between TMEM192 molecules, indicating that TMEM192 dimers are linked by a disulfide bridge between their C-terminal tails. According to the predicted topology, Cys266 would be localized in the reductive milieu of the cytosol where disulfide bridges are generally uncommon. Using immunogold labelling and proteinase protection assays, the localization of the N- and C-termini of TMEM192 on the cytosolic side of the late endosomal/lysosomal membrane was experimentally confirmed. These findings may imply close proximity of the C-termini in TMEM192 dimers and a possible involvement of this part of the protein in dimer assembly.
Chondroitin 4-O-sulfotransferase-1 regulates the chain length of chondroitin sulfate in co-operation with chondroitin N-acetylgalactosaminyltransferase-2
Authors: Izumikawa Tomomi , Okuura Yuka , Koike Toshiyasu , Sakoda Naoki , Kitagawa Hiroshi
Published: February 2011

Previously, we demonstrated that sog9 cells, a murine L cell mutant, are deficient in the expression of C4ST (chondroitin 4-O-sulfotransferase)-1 and that they synthesize fewer and shorter CS (chondroitin sulfate) chains. These results suggested that C4ST-1 regulates not only 4-O-sulfation of CS, but also the length and amount of CS chains; however, the mechanism remains unclear. In the present study, we have demonstrated that C4ST-1 regulates the chain length and amount of CS in co-operation with ChGn-2 (chondroitin N-acetylgalactosaminyltransferase 2). Overexpression of ChGn-2 increased the length and amount of CS chains in L cells, but not in sog9 mutant cells. Knockdown of ChGn-2 resulted in a decrease in the amount of CS in L cells in a manner proportional to ChGn-2 expression levels, whereas the introduction of mutated C4ST-1 or ChGn-2 lacking enzyme activity failed to increase the amount of CS. Furthermore, the non-reducing terminal 4-O-sulfation of N-acetylgalactosamine residues facilitated the elongation of CS chains by chondroitin polymerase consisting of chondroitin synthase-1 and chondroitin-polymerizing factor. Overall, these results suggest that the chain length of CS is regulated by C4ST-1 and ChGn-2 and that the enzymatic activities of these proteins play a critical role in CS elongation.
Functional interactions between ubiquitin E2 enzymes and TRIM proteins
Authors: Napolitano Luisa M. , Jaffray Ellis G. , Hay Ronald T. , Meroni Germana
Published: February 2011

The TRIM (tripartite motif) family of proteins is characterized by the presence of the tripartite motif module, composed of a RING domain, one or two B-box domains and a coiled-coil region. TRIM proteins are involved in many cellular processes and represent the largest subfamily of RING-containing putative ubiquitin E3 ligases. Whereas their role as E3 ubiquitin ligases has been presumed, and in several cases established, little is known about their specific interactions with the ubiquitin-conjugating E2 enzymes or UBE2s. In the present paper, we report a thorough screening of interactions between the TRIM and UBE2 families. We found a general preference of the TRIM proteins for the D and E classes of UBE2 enzymes, but we also revealed very specific interactions between TRIM9 and UBE2G2, and TRIM32 and UBE2V1/2. Furthermore, we demonstrated that the TRIM E3 activity is only manifest with the UBE2 with which they interact. For most specific interactions, we could also observe subcellular co-localization of the TRIM involved and its cognate UBE2 enzyme, suggesting that the specific selection of TRIM–UBE2 pairs has physiological relevance. Our findings represent the basis for future studies on the specific reactions catalysed by the TRIM E3 ligases to determine the fate of their targets.
Accelerated urokinase-receptor protein turnover triggered by interference with the addition of the glycolipid anchor
Authors: Avila Hector , Wang Heng , Chauhan Santosh , Hartig Sean , Boyd Douglas D.
Published: February 2011

u-PAR (urokinase-type plasminogen activator receptor), anchored to the cell surface via a glycolipid moiety, drives tumour progression. We previously reported that colon cancer cells (RKO clone 2 FS2), attenuated for in vivo tumorigenicity, are diminished >15-fold for u-PAR display when compared with their tumorigenic isogenic counterparts (RKO clone 2), this disparity not reflecting altered transcription/mRNA stability. FACS, confocal microscopy and Western blotting using a fused u-PAR–EGFP (enhanced green fluorescent protein) cDNA revealed a >14-fold differential in the u-PAR–EGFP signal between the isogenic cells, ruling out alternate splicing as a mechanism. Although metabolic labelling indicated similar synthesis rates, pulse–chase revealed accelerated u-PAR–EGFP turnover in the RKO clone 2 FS2 cells. Expression in RKO clone 2 cells of a u-PAR–EGFP protein unable to accept the glycolipid moiety yielded diminished protein amounts, thus mirroring the low endogenous protein levels evident with RKO clone 2 FS2 cells. Transcript levels for the phosphatidylglycan anchor biosynthesis class B gene required for glycolipid synthesis were reduced by 65% in RKO clone 2 FS2 cells, and forced overexpression in these cells partially restored endogenous u-PAR. Thus attenuated u-PAR levels probably reflects accelerated turnover triggered by inefficient addition of the glycolipid moiety.
The deubiquitinating enzyme DUB2A enhances CSF3 signalling by attenuating lysosomal routing of the CSF3 receptor
Authors: Meenhuis Annemarie , Verwijmeren Carola , Roovers Onno , Touw Ivo P.
Published: February 2011

Ubiquitination of the CSF3R [CSF3 (colony-stimulating factor 3) receptor] occurs after activated CSF3Rs are internalized and reside in early endosomes. CSF3R ubiquitination is crucial for lysosomal routing and degradation. The E3 ligase SOCS3 (suppressor of cytokine signalling 3) has been shown to play a major role in this process. Deubiquitinating enzymes remove ubiquitin moieties from target proteins by proteolytic cleavage. Two of these enzymes, AMSH [associated molecule with the SH3 domain of STAM (signal transducing adaptor molecule)] and UBPY (ubiquitin isopeptidase Y), interact with the general endosomal sorting machinery. Whether deubiquitinating enzymes control CSF3R trafficking from early towards late endosomes is unknown. In the present study, we asked whether AMSH, UBPY or a murine family of deubiquitinating enzymes could fulfil such a role. This DUB family (deubiquitin enzyme family) comprises four members (DUB1, DUB1A, DUB2 and DUB2A), which were originally described as being haematopoietic-specific and cytokine-inducible, but their function in cytokine receptor routing and signalling has remained largely unknown. We show that DUB2A expression is induced by CSF3 in myeloid 32D cells and that DUB2 decreases ubiquitination and lysosomal degradation of the CSF3R, leading to prolonged signalling. These results support a model in which CSF3R ubiquitination is dynamically controlled at the early endosome by feedback mechanisms involving CSF3-induced E3 ligase (SOCS3) and deubiquitinase (DUB2A) activities.
Male infertility-linked point mutation disrupts the Ca2+ oscillation-inducing and PIP2 hydrolysis activity of sperm PLCζ
Authors: Nomikos Michail , Elgmati Khalil , Theodoridou Maria , Calver Brian L. , Cumbes Bevan , Nounesis Georg , Swann Karl , Lai F. Anthony
Published: February 2011

A male infertility-linked human PLCζ (phospholipase Cζ) mutation introduced into mouse PLCζ completely abolishes both in vitro PIP2 (phosphatidylinositol 4,5-bisphosphate) hydrolysis activity and the ability to trigger in vivo Ca2+ oscillations in mouse eggs. Wild-type PLCζ initiated a normal pattern of Ca2+ oscillations in eggs in the presence of 10-fold higher mutant PLCζ, suggesting that infertility is not mediated by a dominant-negative mechanism.
Biological signalling activity measurements using mass spectrometry
Authors: Cutillas Pedro R. , Jørgensen Claus
Published: February 2011

MS (mass spectrometry) techniques are rapidly evolving to high levels of performance and robustness. This is allowing the application of these methods to the interrogation of signalling networks with unprecedented depth and accuracy. In the present review we discuss how MS-based multiplex quantification of kinase activities and phosphoproteomics provide complementary means to assess biological signalling activity. In addition, we discuss how a wider application of these analytical concepts to quantify kinase signalling will result in a more comprehensive understanding of normal and disease biology at the system level.