bluuebunny/crossref_metadata_2025 huggingface dataset:
Stability Analysis of A Thin Micropolar Fluid Flowing on A Rotating Circular Disk
Authors: Chen C. K. , Lin M. C. , Chen C. I.
Published: March 2011

The stability analysis of a thin micropolar fluid flowing on a rotating circular disk is investigated numerically. The target is restricted to some neighborhood of critical value in the linear stability analysis. First, a generalized nonlinear kinematic model is derived by the long wave perturbation method. The method of normal mode is applied to the linear stability. After the weakly nonlinear dynamics of a film flow is studied by using the method of multiple scales, the Ginzburg-Landau equation is determined to discuss the necessary condition in terms of the various states of subcritical stability, subcritical instability, supercritical stability, and supercritical explosion for the existence of such flow pattern. The modeling results indicate that the rotation number and the radius of circular disk play the significant roles in destabilizing the flow. Furthermore, the micropolar parameter K serves as the stabilizing factor in the thin film flow.
Improved Harmony Search Methods to Replace Variational Principle in Geotechnical Problems
Authors: Cheng Y. M. , Li L. , Fang S. S.
Published: March 2011

Variational principle is an important principle in engineering discipline. This principle is suitable for simple problems where an analytical expression can be determined, but there are many practical problems where the classical variational principle is practically impossible to be applied. In this paper, the authors will try to demonstrate that the variational principle can be replaced by the use of modern artificial intelligence based optimization method (harmony search method) which can be applied to much more complicated problems. Two different improved harmony search algorithms are proposed in this paper. The new algorithms differ from the original algorithm in that: (1) The harmonies are rearranged into several pairs and the better pairs are used to develop several new harmonies; (2) Different probabilities are assigned to different harmonies. The robustness of the proposed methods is demonstrated by using three difficult examples, and the sensitivities of the related optimization parameters are investigated through statistical orthogonal analysis.
Failure Behavior of Two Parallel Pinned/Bolted Composite Joints
Authors: Pakdil M. , Sen F. , Cakan A.
Published: March 2011

In this study, the failure behavior of two parallel pinned/bolted composite joints was investigated, experimentally. The laminated composite plates were produced from glass fibers and epoxy matrix. During the tests, various joint geometries and ply orientations were considered to decide the optimum joint geometry and suitable stacking sequence of the laminated composite plates for two parallel pinned/bolted joints. For these reasons, the distance from the free edge of the plate to hole diameter ratio (E/D) was changed from 1 to 5, the distance between two parallel holes to hole diameter ratio (K/D) was selected as 2 and 5, the distance from the lateral edge of the plate to hole diameter ratio (N/D) was taken as 2 and 3. The laminated plates were composed from 8 laminas to stuck onto together with three different orientations as [0°2 / 30°2]s, [0°2 / 45°2]s and [0°2 / 60°2]s. The experiments involved both pinned and bolted joint. Experimental results indicate that failure behaviors of pinned/bolted composite joints are strictly influenced from both orientations of laminated plates and geometrical parameters.
Structural Analysis of Arches in Plane with a Family of Simple and Accurate Curved Beam Elements Based on Mindlin-Reissner Model
Authors: Tayşi N. , Göĝüş M. T. , Özakça M.
Published: March 2011

In this paper, the basic finite element formulation of a newly developed family of variable thickness, curved,C(0) continuity Mindlin-Reissner model curved beam elements which include shear deformation and rotatory inertia effects is presented. The accuracy, convergence and efficiency of these newly developed curved beam elements are explored through a series of analyses of arch structures and the results are compared with those obtained by other analytical and numerical methods. The comparisons show that the method yields very good results with a relatively small number of elements.
A Frequency Response Based Structural Damage Localization Method Using Proper Orthogonal Decomposition
Authors: Salehi M. , Ziaei-Rad S. , Ghayour M. , Vaziri-Zanjani M.A.
Published: March 2011

Vibration-based structural damage detection has been the focus of attention by many researchers over the last few decades. However, most methods proposed for this purpose utilize extracted modal parameters or some indices constructed based on these parameters. A literature review revealed that few papers have employed Frequency Response Functions (FRFs) for detecting structural damage. In this paper, a technique is presented for damage detection which is based on measured FRFs. Proper Orthogonal Decomposition (POD) has been implemented on spatiotemporal responses in each frequency in order to reduce the dimension of the data. This is based on the concept that the forced harmonic response of a linear vibrating system can be fully captured utilizing a single basis vector. A different approach is also presented in this paper in which POD is applied to the frequency domain data. Operational Deflection Shapes (ODSs) have been decomposed using POD to localize the damage. The efficiency of the method is demonstrated through some numerical and experimental case studies.
Shock Attenuation of Intervertebral Disc Following Fatigue Loading
Authors: Chiang C.-K. , Yang C.-L. , Chen W.-C. , Chang C.-H. , Huang S.-C. , Wang J.-L.
Published: March 2011

Shock absorption is one of the fundamental biomechanical functions of disc. The knowledge of the effect of fatigue loading, impact energy and contact period on the disc shock attenuation is important in clarifying the risk factors of back pain and evaluating the efficacy of novel disc prosthesis. The purpose of this study is to find the changes of shock attenuation of motion segment after fatigue loading, and the effect of impact energy and contact period on the disc shock attenuation pre and post fatigue loading.

The 3-unit porcine spinal motion segment was used for testing. The impact test was applied pre and post fatigue loading. Impact energy and contact period were controlled in the experiment. Shock attenuation properties, including the acceleration attenuation (AA) of disc, force transmissibility (FT) and phase delay of force (PDF) of motion segment, were calculated from the acceleration and force responses.

The results showed that the shock attenuation properties (acceleration attenuation and force transmissibility) decreased post fatigue. The disc acceleration attenuation was independent of impact energy and contact period. The disc acceleration attenuation was 0.78 (−1.06dB) pre fatigue and 1.04 (0.14dB) post fatigue. The force transmissibility of motion segment decreased post fatigue only during short contact period. The phase delay of force did not change significantly post fatigue.

We found that the fatigue loading decreased the disc shock attenuation. The disc was at higher risk of injury following fatigue loading even at a mild impact loading. The disc acceleration attenuation was invariant of impact energy and contact period, but decreased post fatigue. The disc acceleration attenuation is a good index to evaluate the degree of fatigue injury.
Scattering of Sh-Wave by Cylindrical Inclusion Near Interface in Bi-Material Half-Space
Authors: Qi H. , Yang J. , Shi Y.
Published: March 2011

Green's function and complex function methods are used here to investigate the problem of the scattering of SH-wave by a cylindrical inclusion near interface in bi-material half-space. Firstly, Green's function was constructed which was an essential solution of displacement field for an elastic right-angle space possessing a cylindrical inclusion while bearing out-of-plane harmonic line source load at any point of its vertical boundary. Secondly, the bi-material media was divided into two parts along the vertical interface using the idea of interface “conjunction”, then undetermined anti-plane forces were loaded at the linking sections respectively to satisfy continuity conditions, and a series of Fredholm integral equations of first kind for determining the unknown forces could be set up through continuity conditions on surface. Finally, some examples for dynamic stress concentration factor of the cylindrical elastic inclusion are given. Numerical results show that dynamic stress concentration factor is influenced by interfaces, free boundary and combination of different media parameters.
Study of Hazard Rate Functions on the Cumulative Damage Phenomenon
Authors: Wang K. S.
Published: March 2011

In this paper different failure mechanisms which yield cumulative damage are investigated through two types of hazard rate functions. They have been studied during the past two decades. Type A was developed early by assuming the hazard rate as a function of reliability. There are two kinds of trend, one follows the negative logistic decay model, the other the negative Gompertz decay. Some modifications are suggested according to the failure tendency and convenience of fittings. Type B is developed recently by assuming the hazard rate as a function of the expected operation time, T, which is defined as the integration of reliability over the time, normalized by the mean-time-between-failure. In both types the proposed hazard rates grow with the time monotonically. Typical examples are taken to examine these models, meanwhile the comparisons with the Weibull-typed distribution are also made. The results show that the most of proposed relations are successful in the expression of cumulative damage phenomenon, especially the Type B is a better choice even compared with the Weibull-typed description in some respects. The advantages of the models are discussed based on the physical meanings involved in the parameters.
A Novel Inflatable Belt-Type Clamp in Open Heart Surgery
Authors: Wen C.-Y. , Lee C.-Y. , Yu H.-Y. , Chang H.-T.
Published: March 2011

In this study, a novel inflatable belt-type clamp is introduced and its performance is verified. Finite element simulations are performed to compare the performance of three different aorta clamping systems. In every case, the aorta is modeled as a simple hollow cylinder made of linearly elastic material. For a traditional surgical clamp in which the jaws remain inclined to one another as they close around the aorta, the maximum normal stress within the aorta wall is found to be 806kPa. It is shown that the numerical results are in good qualitative agreement with the experimental results obtained using a pressure sensitive film. The simulation results for a modified clamp in which the jaws remain parallel during the clamping operation show that the maximum normal stress is reduced to 222kPa. However, two regions of maximum stress are induced within the aorta wall. Finally, the numerical results for a novel inflatable belt-type clamp show that the maximum normal stress is equal to approximately 221kPa. In contrast to the modified clamp, the stress is uniformly distributed around the perimeter of the aorta, and thus the risk of aortic dissection is significantly reduced.
Kelvin Ship Wake in the Wind Waves Field and on the Finite Sea Depth
Authors: Fang M.-C. , Yang R.-Y. , Shugan I. V.
Published: March 2011

A kinematics model of the ship wake in the presence of surface waves, generated by wind is presented. It was found that the stationary wave structure behind the ship covered a wedge region with the 16.9° half an angle at the top of the wake and only divergent waves are present in a ship wake for co propagating wind waves. Wind waves field directed at some nonzero angle to the ship motion can cause essential asymmetry of the wake and compressing of its windward half. The extension of Whitham-Lighthill kinematics theory of ship wake for the intermediate sea depth is also presented. The ship wake structure essentially depends from the Froude (Fr) number based on the value of the sea depth and ship velocity. For Froude number less than unit both longitudinal and cross waves are presented in the wake region and Kelvin wake angle increased with Fr. For Fr > 1 wake angle decreased with Froude number and finally only divergent waves are presented in the very narrow ship wake.
Stratarchical Party Organization and Party Finance in Canada
Authors: Coletto David , Jansen Harold J. , Young Lisa
Published: March 2011

Abstract. Based on an examination of constitutional and other party documents, Canadian political parties have been described as stratarchically organized (Carty, 2002). We identify four models of internal party financial flows that correspond to different models of internal party organization. We then trace the financial flows into and within the four major Canadian political parties from 2004 to 2007 with a view to identifying the model of party organization that these flows indicate. Our evidence in some respects supports Carty's assertion that Canadian parties are stratarchically organized, but it also suggests that changes to the regulatory regime governing political finance have contributed to a centralization of power at the level of the national party and at the expense of candidates and local associations. This centralizing tendency is significant, as it may disrupt the bargain that underlies the stratarchical organization of Canadian parties.

Résumé. À la lumière d'une revue des constitutions et de divers autres documents des partis politiques canadiens, ces derniers ont été décrits comme étant organisés de manière stratarchique (Carty, 2002). Nous dégageons quatre modèles de flux monétaires internes des partis qui correspondent à différents modèles d'organisation interne des partis politiques. Nous retraçons les entrées de fonds des quatre principaux partis politiques canadiens et leur distribution interne de 2004 à 2007 en vue d'identifier le modèle d'organisation de parti qui correspond à ces flux monétaires. Sous certains rapports, nos résultats appuient l'argument de Carty affirmant que les partis canadiens sont organisés de manière stratarchique, mais ils suggèrent aussi que les changements apportés au régime régulateur gouvernant le financement politique ont contribué à une centralisation du pouvoir au niveau national des partis et ce aux dépens des candidats et des associations locales. Cette tendance centralisatrice est importante, car elle peut rompre le compromis qui sous-tend l'organisation stratarchique des partis politiques canadiens.
Women Lawyers before the Supreme Court of Canada
Authors: Kaheny Erin B. , Szmer John J. , Sarver Tammy A.
Published: March 2011

Abstract. Recent work by Szmer, Sarver, and Kaheny (2010) exploring US Supreme Court decision making has suggested that lawyer gender might play a role in influencing judicial voting behaviour. Specifically, while women lawyers were not revealed to have a more difficult time winning cases before the US Supreme Court, the study did suggest they face a tougher challenge in gaining support from the more conservative justices on that bench. Here, we test whether women lawyers face similar challenges before the SCC. Our findings do not reveal any disadvantage for litigation teams with larger proportions of women and, in most instances, such teams have an advantage. Specifically, in our model of civil rights and liberties votes, litigation team gender had no bearing on individual SCC justice decisions. However, in a pooled model of all issues combined and in separate models of criminal and economic votes, SCC justices were more likely to side with litigation teams with larger proportions of women lawyers.

Résumé. Une étude récente de Szmer, Sarver et Kaheny (2010) explore la manière dont la Cour suprême des États-Unis prend ses décisions, suggérant que le sexe des avocats pourrait avoir une influence sur le comportement décisionnel des juges. Plus spécifiquement, bien que les avocates n'aient pas plus de difficulté que leurs collègues masculins à gagner leurs procès à la Cour suprême des États-Unis, l'étude suggère que leur plus grand défi est d'obtenir le soutien des juges plus traditionnels de cette cour. Dans le présent article, nous cherchons à déterminer si les avocates canadiennes font face à un défi semblable à la Cour suprême du Canada. Les résultats de notre étude ne révèlent aucun désavantage pour les équipes d'avocats comprenant plus de femmes et dans la plupart des cas, ces équipes bénéficient même d'un avantage. Plus précisement, dans notre modèle décisionnel en matière de droits et libertés civiles, le sexe des membres des équipes d'avocats n'avait aucune incidence sur les décisions individuelles des juges de la Cour suprême du Canada. Cependant, dans un modèle commun réunissant tous les types de dossiers et dans des modèles séparés pour les décisions sur des dossiers criminels et financiers, les juges de la Cour suprême du Canada étaient plus enclins à prendre parti pour des équipes comportant une plus grande proportion d'avocates.
Defining Narratives of Identity in Canadian Political Science: Accounting for the Absence of Race
Authors: Nath Nisha
Published: March 2011

Abstract.This article maps how Canadian political science has considered and shaped the logic of “identity” across the institutional, societal and governance dimensions of this disciplinary subfield. Focusing on the ubiquitous analytic absence of “race” in the mainstream literature, this article argues that mainstream Canadian political science reproduces a logic that limits the conversation to particular dimensions of ‘identity’ (‘identity’ as a basis of political action, a collective phenomenon denoting sameness and a core aspect of individual/collective selfhood) at the expense of others (‘identity’ as a product of social or political action, a product of multiple and competing discourses and a governmentality). In addition to this logic of ‘identity’, eight methodological tendencies in the mainstream literature further impede analyses of ‘race’. By challenging these methodological tendencies, abandoning ‘identity’ as ananalyticcategory and reflecting on the consequences of deactivating and erasing ‘race’, Canadian political scientists may become better equipped to interrogate the operating logic of ‘identity’, to substantively incorporate ‘race’ as a conceptual, analytic and explanatory device, and perhaps most critically, begin to redefine the canon.

Résumé.Cet article retrace la manière dont la science politique canadienne a considéré et façonné la logique de «l'identité» dans certaines dimensions particulières de cette discipline, soit celles des institutions, de la société et de la gouvernance. En se concentrant sur l'absence prédominante du concept de «race» dans les analyses de la littérature conventionnelle, l'article soutient que la science politique canadienne dans la ligne du courant dominant reproduit une logique qui limite la conversation à certaines dimensions de «l'identité» (soit «l'identité» en tant que base de l'action politique, en tant que phénomène dénotant l'uniformité et en tant qu'aspect essentiel du moi individuel ou collectif) au détriment des autres (soit «l'identité» en tant que produit de l'action politique ou sociale, produit de discours multiples et rivaux, et gouvernementalité). Outre cette logique de «l'identité», huit tendances méthodologiques de la littérature conventionnelle entravent davantage les analyses de la «race». En contestant ces tendances méthodologiques, en abandonnant «l'identité» en tant que catégorieanalytiqueet en réfléchissant aux conséquences de la désactivation et de l'effacement de la «race», les politicologues canadiens pourraient devenir mieux équipés pour interroger la logique opérante de «l'identité», pour incorporer la «race» de manière substantielle en tant que dispositif conceptuel, analytique et explicatif, et peut-être le plus important, pour commencer à redéfinir le canon.
Replying to the anti-God challenge: a God without moral character acts well
Authors: FORREST PETER
Published: March 2011

Several authors, including Stephen Law in this journal, have argued that the case for an evil God is (about) as strong as for a good God. In this article I take up the challenge on behalf of theists who, like Richard Swinburne, argue for an agent of unrestricted power and knowledge as the ultimate explanation of all contingent truths. I shall argue that an evil God is much less probable than a good one. I do so by (1) distinguishing the analogical predication of ‘good’ or ‘evil’ of God from the literal predication, (2) interpreting ‘acting in a morally good way’ to mean ‘acting like a good consequentialist’, and (3) relying on anaxiarchistthesis about agency that is congenial to theists and perhaps even presupposed by theism.
APPROXIMATE RESULTS FOR A GENERALIZED SECRETARY PROBLEM
Authors: Dietz Chris , van der Laan Dinard , Ridder Ad
Published: March 2011

A version of the classical secretary problem is studied, in which one is interested in selecting one of the b best out of a group of n differently ranked persons who are presented one by one in a random order. It is assumed that b ≥ 1 is a preassigned number. It is known, already for a long time, that for the optimal policy, one needs to compute b position thresholds (for instance, via backward induction). In this article we study approximate policies that use just a single or a double position threshold, albeit in conjunction with a level rank. We give exact and asymptotic (as n → ∞) results, which show that the double-level policy is an extremely accurate approximation.
RATIO MONOTONICITY FOR TAIL PROBABILITIES IN THE RENEWAL RISK MODEL
Authors: Psarrakos Georgios , Tsatsomeros Michael
Published: March 2011

A renewal model in risk theory is considered, where $\overline{H}(u,y)$ is the tail of the distribution of the deficit at ruin with initial surplus u and $\overline{F}(y)$ is the tail of the ladder height distribution. Conditions are derived under which the ratio $\overline{H}(u,y)/\overline{F}(u+y)$ is nondecreasing in u for any y≥0. In particular, it is proven that if the ladder height distribution is stable and DFR or phase type, then the above ratio is nondecreasing in u. As a byproduct of this monotonicity, an upper bound and an asymptotic result for $\overline{H}(u,y)$ are derived. Examples are given to illustrate the monotonicity results.
OIL PRODUCTION MODELS WITH NORMAL RATE CURVES
Authors: Stark Dudley
Published: March 2011

The normal curve has been used to fit the rate of both world and US oil production. In this article we give the first theoretical basis for these curve fittings. It is well known that oil field sizes can be modeled by independent samples from a lognormal distribution. We show that when field sizes are lognormally distributed, the starting time of the production of a field is approximately a linear function of the logarithm of its size, and production of a field occurs within a small enough time interval, then the resulting total rate of production is close to being a normal curve.
ACTIVE REDUNDANCY ALLOCATIONS IN SERIES SYSTEMS
Authors: Misra Neeraj , Misra Amit Kumar , Dhariyal Ishwari Dutt
Published: March 2011

We consider the problem of optimally allocating one/two active spares in series systems. Lifetimes of different configurations are compared with respect to the reversed failure rate order, the failure rate order, the increasing concave order, and the stochastic precedence order.
Linking farmers to community stores to increase consumption of local produce: a case study of the Navajo Nation
Authors: Setala Ashley , Gittelsohn Joel , Speakman Kristen , Oski Jane , Martin Tammy , Moore Regina , Tohannie Marcella , Bleich Sara N
Published: March 2011

Objective

To understand the barriers to farmer participation in Farm-to-Table (F2T) programmes and to identify possible solutions to these obstacles.

Design

Cross-sectional analysis of farmer perspectives on F2T programmes.

Setting

Three service units on the Navajo Nation (Chinle, Tuba City and Fort Defiance).

Subjects

Forty-four Navajo farmers.

Results

Most participants reported that farming on the Navajo Nation is getting harder (61 %) but that it is very important to maintain Navajo farming traditions (98 %). A modest number of farmers (43 %) expressed interest in participating in an F2T programme. All farmers reported that childhood obesity was a very serious or serious problem in the Navajo Nation. The farmers expressed support for an F2T programme if key barriers to farming, including water access and pest control, could be addressed. Key barriers to participation identified included lack of fruits and vegetables to sell, sale price of crops and lack of certification of produce by the US Food and Drug Administration.

Conclusions

Navajo farmers are aware of the burden of childhood obesity on the Navajo Nation and feel that an F2T programme could be beneficial. To successfully implement a Farm-to-Table programme, the barriers to participation identified will need to be addressed.
Incomplete Harmonization Contracts in International Economic Law: Report of the Panel, China – Measures Affecting the Protection and Enforcement of Intellectual Property Rights, WT/DS362/R, adopted 20 March 2009
Authors: SAGGI KAMAL , TRACHTMAN JOEL P.
Published: March 2011

In China – Measures Affecting the Protection and Enforcement of Intellectual Property Rights, the Panel addressed three main issues:

1.

the relationship between China's censorship laws and its obligations to protect copyright under the WTO Agreement on Trade Related Intellectual Property Rights (‘TRIPS’);

2.

China's obligations under TRIPS to ensure that its customs authorities be empowered to dispose properly of confiscated goods that infringe intellectual property rights;

3.

whether China's volume and value of goods thresholds for application of criminal procedures and penalties with respect to trademark counterfeiting or copyright piracy comply with TRIPS requirements for application of criminal procedures and penalties.
US Compliance with WTO Rulings on Zeroing in Anti-Dumping
Authors: HOEKMAN BERNARD , WAUTERS JASPER
Published: March 2011

This paper reviews the WTO Appellate Body Reports on United States–Zeroing (EC) (Article 21.5 DSU – EC) (WT/DS294/AB/RW, 14 May 2009) and United States–Zeroing (Japan) (Article 21.5 DSU – Japan) (WT/DS322/AB/RW, 18 August 2009). The Appellate Body found that the United States had not brought its anti-dumping measures into compliance with the WTO Anti-Dumping Agreement as it continued to use zeroing in annual reviews of anti-dumping orders. We argue that this conclusion – based on a complicated discussion of what constitutes a ‘measure taken to comply’ – could have been reached through a much simpler and direct argument. Continued noncompliance by the United States generates costs to traders targeting the United States and the trading system more generally. We argue that from a broader WTO compliance perspective consideration should be given to stronger multilateral surveillance of anti-dumping practice by all WTO members and to more analysis and effective communication by economists regarding the costs of zeroing and anti-dumping practices more generally.
Appellate Body Ruling inChina–Publications and Audiovisual Products
Authors: ROESSLER FRIEDER
Published: March 2011

I would like to add to the analyses of the authors comments on two questions: First, how should measures falling under the GATT be distinguished from those falling under the GATS? Second, could a measure inconsistent with one WTO agreement be justified by an exception contained in another?
‘Optimal’ Retaliation in the WTO – a commentary on the Upland Cotton Arbitration
Authors: GROSSMAN GENE M. , SYKES ALAN O.
Published: March 2011

The Upland Cotton case raises a range of interesting issues regarding the rationale for retaliation in the WTO system and the proper approach to its calibration. These include: Should the approach to retaliation differ in cases involving prohibited or actionable subsidies? When should cross-retaliation be allowed? Should retaliation be based only on the harm to the complaining nation, or to other nations as well? And, most importantly, what economic content can be given to the standard of countermeasures ‘equivalent to the level of nullification or impairment’? We address these and other issues from both a legal and economic perspective, with particular attention to the question of what level of retaliation will restore the lost welfare of the complaining nation.
Precalculated phase equilibrium models for geophysical properties of the crust and mantle as a function of composition
Authors: Zunino A. , Connolly J. A. D. , Khan A.
Published: March 2011

The use of phase equilibrium calculations to compute physical properties of rocks has become commonplace in geophysical modeling. Typically, the phase equilibrium calculations are used to construct two‐dimensional tables of rock properties as a function of pressure and temperature. We document a computer program that can be used to assemble a three‐dimensional table that accounts for compositional variations from such two‐dimensional tables. A user‐selected interpolation scheme is used to recover data from the tables as continuous function of its independent variables. We illustrate the utility of the program using two examples. The first explores the effect of water content of an average continental crust composition. As water content is the primary parameter controlling the amount of melt and/or low‐density fluid present in the crust, this model provides a basis for assessing the impact of fluids on the geophysical properties of the crust. In the second example, we model the mantle composition as a mixture between harzburgitic and basaltic end‐members. We show that for purposes of seismic velocity calculations, the continuum model is well approximated by interpolation from a table in which the compositional variable is sampled at 10% intervals. The tables for both examples are provided electronically as ready‐to‐use geophysical tools.
Temperature calibration of Mg/Ca ratios in the intermediate water benthic foraminifer Hyalinea balthica
Authors: Rosenthal Yair , Morley Audrey , Barras Christine , Katz Miriam E. , Jorissen Frans , Reichart Gert‐Jan , Oppo Delia W. , Linsley Braddock K.
Published: March 2011

Core top samples from Indonesian and northeast Atlantic depth transects were used to calibrate Mg/Ca and δ18O in tests of the calcitic benthic foraminifer Hyalinea balthica to bottom water temperature between 4°C and 13°C. This shallow infaunal species is primarily abundant in neritic to upper bathyal sediments (<600 m). Both linear and exponential calibrations suggest a temperature sensitivity of ∼12% per °C that is ∼4 times higher than observed in other species of deep‐sea benthic foraminifera. Culture experiments support the core top calibration. We find no discernible effect of salinity and saturation on Mg/Ca. Comparison between the measured benthic foraminiferal δ18O and predicted equilibrium values suggests that on average H. balthica δ18O is 0.64‰ ± 0.13‰ lower than predicted from the equilibrium composition. To test the reliability of using paired H. balthica Mg/Ca and δ18O measurements for reconstructing seawater δ18Osw and salinity, we apply this calibration to another depth transect from Cape Ghir off NW Africa, which was not included in the calibration. Based on error analysis of the calibration data and this validation test, we show that the uncertainty of reconstructing bottom water temperature and salinity from paired Mg/Ca and δ18O measurements of H. balthica is better than ±0.7°C and ±0.69 practical salinity scale, respectively. The small uncertainties allow for the reconstruction of seawater density to better than 0.3σθ units, which is precise enough for the identification of specific water masses and reconstruction of changes in their properties. We propose that the relatively high Mg content and temperature sensitivity of H. balthica might be due to minor, biologically mediated contribution of high‐Mg calcite to the primarily low Mg calcite test, which is influenced by the ambient temperature. This hypothesis, if correct, suggests that benthic species with relatively high Mg/Ca may be better suited for deepwater temperature reconstructions than species that have thus far been more commonly used.
A physically based description of floodplain inundation dynamics in a global river routing model
Authors: Yamazaki Dai , Kanae Shinjiro , Kim Hyungjun , Oki Taikan
Published: March 2011

Current global river routing models do not represent floodplain inundation dynamics realistically because the storage and movement of surface waters are regulated by small‐scale topography rather than the commonly used spatial resolution of global models. In this study, we propose a new global river routing model, CaMa‐Flood, which explicitly parameterizes the subgrid‐scale topography of a floodplain, thus describing floodplain inundation dynamics. The relationship between water storage, water level, and flooded area in the model is decided on the basis of the subgrid‐scale topographic parameters based on 1 km resolution digital elevation model. Horizontal water transport is calculated with a diffusive wave equation, which realizes the backwater effect in flat river basins. A set of global‐scale river flow simulations demonstrated an improved predictability of daily‐scale river discharge in many major world rivers by incorporating the floodplain inundation dynamics. Detailed analysis of the simulated results for the Amazon River suggested that introduction of the diffusive wave equation is essential for simulating water surface elevation realistically. The simulated spatiotemporal variation of the flooded area in the Amazon basin showed a good correlation with satellite observations, especially when the backwater effect was considered. The improved predictability for daily river discharge, water surface elevation, and inundated areas by the proposed model will promote climate system studies and water resource assessments.
Hydroclimatic projections for the Murray‐Darling Basin based on an ensemble derived from Intergovernmental Panel on Climate Change AR4 climate models
Authors: Sun Fubao , Roderick Michael L. , Lim Wee Ho , Farquhar Graham D.
Published: March 2011

We assess hydroclimatic projections for the Murray‐Darling Basin (MDB) using an ensemble of 39 Intergovernmental Panel on Climate Change AR4 climate model runs based on the A1B emissions scenario. The raw model output for precipitation, P, was adjusted using a quantile‐based bias correction approach. We found that the projected change, ΔP, between two 30 year periods (2070–2099 less 1970–1999) was little affected by bias correction. The range for ΔP among models was large (∼±150 mm yr−1) with all–model run and all‐model ensemble averages (4.9 and −8.1 mm yr−1) near zero, against a background climatological P of ∼500 mm yr−1. We found that the time series of actually observed annual P over the MDB was indistinguishable from that generated by a purely random process. Importantly, nearly all the model runs showed similar behavior. We used these facts to develop a new approach to understanding variability in projections of ΔP. By plotting ΔP versus the variance of the time series, we could easily identify model runs with projections for ΔP that were beyond the bounds expected from purely random variations. For the MDB, we anticipate that a purely random process could lead to differences of ±57 mm yr−1 (95% confidence) between successive 30 year periods. This is equivalent to ±11% of the climatological P and translates into variations in runoff of around ±29%. This sets a baseline for gauging modeled and/or observed changes.
Genomic and proteomic analyses of the coral pathogen Vibrio coralliilyticus reveal a diverse virulence repertoire
Authors: de O Santos Eidy , Alves Nelson , Dias Graciela M , Mazotto Ana Maria , Vermelho Alane , Vora Gary J , Wilson Bryan , Beltran Victor H , Bourne David G , Le Roux Frédérique , Thompson Fabiano L
Published: March 2011

Vibrio coralliilyticus has been implicated as an important pathogen of coral species worldwide. In this study, the nearly complete genome of Vibrio coralliilyticus strain P1 (LMG23696) was sequenced and proteases implicated in virulence of the strain were specifically investigated. The genome sequence of P1 (5 513 256 bp in size) consisted of 5222 coding sequences and 58 RNA genes (53 tRNAs and at least 5 rRNAs). Seventeen metalloprotease and effector (vgrG, hlyA and hcp) genes were identified in the genome and expressed proteases were also detected in the secretome of P1. As the VcpA zinc-metalloprotease has been considered an important virulence factor of V. coralliilyticus, a vcpA deletion mutant was constructed to evaluate the effect of this gene in animal pathogenesis. Both wild-type and mutant (ΔvcpA) strains exhibited similar virulence characteristics that resulted in high mortality in Artemia and Drosophila pathogenicity bioassays and strong photosystem II inactivation of the coral dinoflagellate endosymbiont (Symbiodinium). In contrast, the ΔvcpA mutant demonstrated higher hemolytic activity and secreted 18 proteins not secreted by the wild type. These proteins included four types of metalloproteases, a chitinase, a hemolysin-related protein RbmC, the Hcp protein and 12 hypothetical proteins. Overall, the results of this study indicate that V. coralliilyticus strain P1 has a diverse virulence repertoire that possibly enables this bacterium to be an efficient animal pathogen.
Nitrogen fixation and transfer in open ocean diatom–cyanobacterial symbioses
Authors: Foster Rachel A , Kuypers Marcel M M , Vagner Tomas , Paerl Ryan W , Musat Niculina , Zehr Jonathan P
Published: March 2011

Many diatoms that inhabit low-nutrient waters of the open ocean live in close association with cyanobacteria. Some of these associations are believed to be mutualistic, where N2-fixing cyanobacterial symbionts provide N for the diatoms. Rates of N2 fixation by symbiotic cyanobacteria and the N transfer to their diatom partners were measured using a high-resolution nanometer scale secondary ion mass spectrometry approach in natural populations. Cell-specific rates of N2 fixation (1.15–71.5 fmol N per cell h−1) were similar amongst the symbioses and rapid transfer (within 30 min) of fixed N was also measured. Similar growth rates for the diatoms and their symbionts were determined and the symbiotic growth rates were higher than those estimated for free-living cells. The N2 fixation rates estimated for Richelia and Calothrix symbionts were 171–420 times higher when the cells were symbiotic compared with the rates estimated for the cells living freely. When combined, the latter two results suggest that the diatom partners influence the growth and metabolism of their cyanobacterial symbionts. We estimated that Richelia fix 81–744% more N than needed for their own growth and up to 97.3% of the fixed N is transferred to the diatom partners. This study provides new information on the mechanisms controlling N input into the open ocean by symbiotic microorganisms, which are widespread and important for oceanic primary production. Further, this is the first demonstration of N transfer from an N2 fixer to a unicellular partner. These symbioses are important models for molecular regulation and nutrient exchange in symbiotic systems.
Effect of warming and drought on grassland microbial communities
Authors: Sheik Cody S , Beasley William Howard , Elshahed Mostafa S , Zhou Xuhui , Luo Yiqi , Krumholz Lee R
Published: March 2011

The soil microbiome is responsible for mediating key ecological processes; however, little is known about its sensitivity to climate change. Observed increases in global temperatures and alteration to rainfall patterns, due to anthropogenic release of greenhouse gases, will likely have a strong influence on soil microbial communities and ultimately the ecosystem services they provide. Therefore, it is vital to understand how soil microbial communities will respond to future climate change scenarios. To this end, we surveyed the abundance, diversity and structure of microbial communities over a 2-year period from a long-term in situ warming experiment that experienced a moderate natural drought. We found the warming treatment and soil water budgets strongly influence bacterial population size and diversity. In normal precipitation years, the warming treatment significantly increased microbial population size 40–150% but decreased diversity and significantly changed the composition of the community when compared with the unwarmed controls. However during drought conditions, the warming treatment significantly reduced soil moisture thereby creating unfavorable growth conditions that led to a 50–80% reduction in the microbial population size when compared with the control. Warmed plots also saw an increase in species richness, diversity and evenness; however, community composition was unaffected suggesting that few phylotypes may be active under these stressful conditions. Our results indicate that under warmed conditions, ecosystem water budget regulates the abundance and diversity of microbial populations and that rainfall timing is critical at the onset of drought for sustaining microbial populations.
Behavioral Transitions and Weight Change Patterns Within the PREMIER Trial
Authors: Bartfield Jessica K. , Stevens Victor J. , Jerome Gerald J. , Batch Bryan C. , Kennedy Betty M. , Vollmer William M. , Harsha David , Appel Lawrence J. , Desmond Renee , Ard Jamy D.
Published: March 2011

Little is known about the transition in behaviors from short‐term weight loss to maintenance of weight loss. We wanted to determine how short‐term and long‐term weight loss and patterns of weight change were associated with intervention behavioral targets. This analysis includes overweight/obese participants in active treatment (n = 507) from the previously published PREMIER trial, an 18‐month, multicomponent lifestyle intervention for blood pressure reduction, including 33 intervention sessions and recommendations to self‐monitor food intake and physical activity daily. Associations between behaviors (attendance, recorded days/week of physical activity, food records/week) and weight loss of ≥5% at 6 and 18 months were examined using logistic regression. We characterized the sample using 5 weight change categories (weight gained, weight stable, weight loss then relapse, late weight loss, and weight loss then maintenance) and analyzed adherence to the behaviors for each category, comparing means with ANOVA. Participants lost an average of 5.3 ± 5.6 kg at 6 months and 4.0 ± 6.7 kg (4.96% of body weight) by 18 months. Higher levels of attendance, food record completion, and recorded days/week of physical activity were associated with increasing odds of achieving 5% weight loss. All weight change groups had declines in the behaviors over time; however, compared to the other four groups, the weight loss/maintenance group (n = 154) had statistically less significant decline in number of food records/week (48%), recorded days/week of physical activity (41.7%), and intervention sessions attended (12.8%) through 18 months. Behaviors associated with short‐term weight loss continue to be associated with long‐term weight loss, albeit at lower frequencies. Minimizing the decline in these behaviors may be important in achieving long‐term weight loss.
Adiponectin Changes in Relation to the Macronutrient Composition of a Weight‐Loss Diet
Authors: Summer Suzanne S. , Brehm Bonnie J. , Benoit Stephen C. , D'Alessio David A.
Published: March 2011

Adiponectin is an adipose‐derived protein with beneficial metabolic effects. Low adiponectin is associated with obesity and related diseases. Significant weight loss increases adiponectin, reducing disease risk. This study compared the effects of two weight‐loss diets with different macronutrient compositions on adiponectin. Eighty‐one obese women in two cohorts were randomized to a low‐fat (LF) or a low‐carbohydrate (LC) diet. All subjects underwent equivalent weight‐loss intervention, with weight and other measures assessed at baseline and after 6 (cohort I) or 4 (cohort II) months. Body fat was measured by dual energy X‐ray absorptiometry. Adiponectin was measured by radioimmunoassay. Diet intake was assessed using 24‐h recalls and 3‐day diet records. Data were analyzed via t‐tests and repeated‐measures factorial ANOVA using time, diet, and replicate (cohort I vs. cohort II) as factors. Age, weight, body fat, BMI, adiponectin, and diet were similar at baseline. Following intervention, macronutrient composition of the diet was vastly different between the groups, reflecting the assigned diet. Both groups lost weight and body fat (P < 0.001), with effect in LC dieters greater than LF dieters (−9.1 kg vs. −4.97 kg weight, P < 0.05 and −5.45 kg vs. −2.62 kg fat, P < 0.001). Adiponectin increased in the LC (+1.92 mcg/ml, P < 0.01), but not the LF (+0.86 mcg/ml, P = 0.81), group. There was no correlation between weight loss and increase in adiponectin. These results confirm that diet‐induced loss of weight and body fat is associated with increased adiponectin concentrations. This effect is evident with weight loss of 10% or more, and may be greater with LC diets.
New Gestational Weight Gain Guidelines: An Observational Study of Pregnancy Outcomes in Obese Women
Authors: Einerson Brett D. , Huffman Josephine K. , Istwan Niki B. , Rhea Debbie J. , Joy Saju D.
Published: March 2011

In 2009, the Institute of Medicine (IOM) revised their pregnancy weight gain guidelines, recommending gestational weight gain of 11–20 pounds for women with prepregnancy BMI >30 kg/m2. We investigated the potential influence of the new guidelines on perinatal outcomes using a retrospective analysis (n = 691), comparing obese women who gained weight during pregnancy according to the new guidelines to those who gained weight according to traditional recommendations (25–35 pounds). We found no statistical difference between the two weight gain groups in infant birth weight, cesarean delivery rate, pregnancy‐related hypertension, low birth weight infants, macrosomia, neonatal intensive care unit admissions, or total nursery days. Despite showing no evidence of other benefits, our data suggest that obese women who gain weight according to new IOM guidelines are no more likely to have low birth weight infants. In the absence of national consensus on appropriate gestational weight gain guidelines, our data provide useful data for clinicians when providing evidence‐based weight gain goals for their obese patients.
Game Changer
Authors: McLeod Lateef
Published: March 2011

Individuals with significant communication challenges need to communicate across many different venues. The author, from the perspective of an individual who uses AAC, discusses the strengths and weaknesses of both traditional AAC technologies and new mobile AAC technologies. He describes how access to AAC has allowed him to fulfill his dreams as a presenter and writer. He successfully manages a blog in San Francisco, writes grants, and has published his first book of poetry. Not one AAC device fits all of his communication needs; however, access to mobile technology tools has increased his flexibility across environments and given him another successful tool for communication.
The iPad: A Cool Communicator on the Go
Authors: Hyatt Glenda Watson
Published: March 2011

Glenda Watson Hyatt, Web accessibility consultant, blogger, and user of AAC, shares her perspective on new mobile AAC technologies. A history of Glenda's use of AAC is chronicled from her early low-tech strategies to her recent embracing of new mobile AAC technologies. She recounts purchasing an iPad and her early experiences attempting to use it as an AAC system in a variety of contexts. Strengths, weaknesses, and projections for the future are highlighted in this personal sharing of a user perspective.