bluuebunny/crossref_metadata_2025 huggingface dataset:
Motor Cortex Preactivation by Standing Facilitates Word Retrieval in Aphasia
Authors: Meinzer Marcus , Breitenstein Caterina , Westerhoff Ursula , Sommer Jens , Rösser Nina , Rodriguez Amy Denise , Harnish Stacy , Knecht Stefan , Flöel Agnes
Published: October 2010

Background and Objectives. A tight link between linguistic functions and activation of motor areas has been consistently reported, indicating that the 2 systems share functional neural resources. Few efforts have been made to explore whether this knowledge could aid the rehabilitation of aphasia. Methods. The authors assessed whether preactivation of the leg motor cortex during standing, compared with sitting, can facilitate language production in patients with chronic aphasia. In a cross-over within-subject design, the authors assessed performance on a picture naming task and controlled for effects on processing speed and simple verbal reaction time. Results. They found that standing compared with sitting had a beneficial effect on the number of semantic self-corrections that resulted in correct naming. In the absence of effects on motor or general processing speed, this points to a specific effect on lexical retrieval and selection. This was further corroborated by an error pattern analysis. Successful semantic self-corrections during standing were only found when there was already partial activation of the target semantic network—that is, when self-corrections were preceded by an incorrect but semantically associated naming response. Discussion. These findings show that preactivation of the motor system, which extends beyond the intrinsic link between manual gestures and language, can facilitate lexical access in chronic aphasia and may open new directions in aphasia rehabilitation.
Valve anatomy and function with transthoracic three-dimensional echocardiography: advantages and limitations of instantaneous full-volume color Doppler imaging
Authors: Gonçalves Alexandra , Zamorano José Luis
Published: October 2010

Three-dimensional echocardiography (3DE) is becoming part of everyday clinical practice worldwide. However, 3DE requires adequate electrocardiographic and respiratory gating and it complements instead of replacing bidimensional echocardiography (2D). The instantaneous full-volume echocardiography technique is trying to overcome some of these limitations and to present an effective alternative to 2D echocardiography. In this article we aim to review the contribution of 3DE to our knowledge of anatomic and functional valvular anatomy and the potential advantages of instantaneous full-volume color Doppler echocardiography.
The interplay between tissue plasminogen activator domains and fibrin structures in the regulation of fibrinolysis: kinetic and microscopic studies
Authors: Longstaff Colin , Thelwell Craig , Williams Stella C. , Silva Marta M. C. G. , Szabó László , Kolev Krasimir
Published: October 2010

Regulation of tissue-type plasminogen activator (tPA) depends on fibrin binding and fibrin structure. tPA structure/function relationships were investigated in fibrin formed by high or low thrombin concentrations to produce a fine mesh and small pores, or thick fibers and coarse structure, respectively. Kinetics studies were performed to investigate plasminogen activation and fibrinolysis in the 2 types of fibrin, using wild-type tPA (F-G-K1-K2-P, F and K2 binding), K1K1-tPA (F-G-K1-K1-P, F binding), and delF-tPA (G-K1-K2-P, K2 binding). There was a trend of enzyme potency of tPA > K1K1-tPA > delF-tPA, highlighting the importance of the finger domain in regulating activity, but the differences were less apparent in fine fibrin. Fine fibrin was a better surface for plasminogen activation but more resistant to lysis. Scanning electron and confocal microscopy using orange fluorescent fibrin with green fluorescent protein-labeled tPA variants showed that tPA was strongly associated with agglomerates in coarse but not in fine fibrin. In later lytic stages, delF-tPA-green fluorescent protein diffused more rapidly through fibrin in contrast to full-length tPA, highlighting the importance of finger domain-agglomerate interactions. Thus, the regulation of fibrinolysis depends on the starting nature of fibrin fibers and complex dynamic interaction between tPA and fibrin structures that vary over time.
Functional Annotation, Genome Organization and Phylogeny of the Grapevine (Vitis vinifera) Terpene Synthase Gene Family Based on Genome Assembly, FLcDNA Cloning, and Enzyme Assays
Authors: Martin Diane M , Aubourg Sébastien , Schouwey Marina B , Daviet Laurent , Schalk Michel , Toub Omid , Lund Steven T , Bohlmann Jörg
Published: October 2010

Background

Terpenoids are among the most important constituents of grape flavour and wine bouquet, and serve as useful metabolite markers in viticulture and enology. Based on the initial 8-fold sequencing of a nearly homozygous Pinot noir inbred line, 89 putative terpenoid synthase genes (VvTPS) were predicted by in silico analysis of the grapevine (Vitis vinifera) genome assembly [1]. The finding of this very large VvTPS family, combined with the importance of terpenoid metabolism for the organoleptic properties of grapevine berries and finished wines, prompted a detailed examination of this gene family at the genomic level as well as an investigation into VvTPS biochemical functions.

Results

We present findings from the analysis of the up-dated 12-fold sequencing and assembly of the grapevine genome that place the number of predicted VvTPS genes at 69 putatively functional VvTPS, 20 partial VvTPS, and 63 VvTPS probable pseudogenes. Gene discovery and annotation included information about gene architecture and chromosomal location. A dense cluster of 45 VvTPS is localized on chromosome 18. Extensive FLcDNA cloning, gene synthesis, and protein expression enabled functional characterization of 39 VvTPS; this is the largest number of functionally characterized TPS for any species reported to date. Of these enzymes, 23 have unique functions and/or phylogenetic locations within the plant TPS gene family. Phylogenetic analyses of the TPS gene family showed that while most VvTPS form species-specific gene clusters, there are several examples of gene orthology with TPS of other plant species, representing perhaps more ancient VvTPS, which have maintained functions independent of speciation.

Conclusions

The highly expanded VvTPS gene family underpins the prominence of terpenoid metabolism in grapevine. We provide a detailed experimental functional annotation of 39 members of this important gene family in grapevine and comprehensive information about gene structure and phylogeny for the entire currently known VvTPS gene family.
Interleukins, laminin and epstein - barr virus latent membrane protein 1 (EBV LMP1) Promote metastatic phenotype in nasopharyngeal carcinoma
Authors: Chew Michelle MS , Gan Sook-Yee , Khoo Alan SB , Tan Eng-Lai
Published: October 2010

Background

Nasopharyngeal carcinoma (NPC) is a type of neoplasm that is highly prevalent in East Asia and Africa with Epstein-Barr virus (EBV), genetic, and dietary factors implicated as possible aetiologic factors. Previous studies suggested the association of certain cytokines with the invasion and metastatic properties of NPC. The present study examined the roles of EBV latent membrane protein-1 (LMP1), interleukin-6 (IL-6), interleukin-10 (IL-10), transforming growth factor-beta 1 (TGF-β1) and laminin in the regulation of matrix-metalloproteinases (MMPs) and vascular endothelial growth factor (VEGF) in NPC. The effects of these factors on bmi-1, an oncogene, and ngx6, a tumour suppressor gene, were also investigated.

Methods

TW01 cells expressing LMP1 (TW01-LMP1) were established via transfection with the B95.8 EBV LMP1 gene. Both TW01 and TW01-LMP1 cells were treated with 100 pg/ml IL-6, 1000 pg/ml IL-10 and 100 pg/ml TGF-β1, separately and also in combination at their respective concentration for 48 hours. Treated cells were subjected to laminin adherence assay. The cells were also cultured with and without laminin and assayed for MMP-3, MMP-9 and VEGF production using enzyme-linked immunosorbent assay (ELISA). The cellular apoptotic property was analysed using caspase-3 apoptosis assay. The expression of bmi-1 and ngx6 gene was investigated using real time reverse transcriptase polymerase chain reaction.

Results

LMP1 was found to reduce the adherence of NPC cells towards laminin (p < 0.05) as compared to control. Treatment with IL-6 at 100 pg/ml enhanced the production of MMP-9 in both TW01 and TW01-LMP1 cells (p < 0.05). When cultured on laminin, the levels of MMP-3 and VEGF were significantly increased (p < 0.05) in TW01-LMP1 cells. TW01-LMP1 cells had relatively greater resistance to apoptosis as compared to TW01 cells (p < 0.05). Laminin, IL-6 and LMP1 were found to up-regulate the expression of bmi-1 and suppressed the expression of ngx6.

Conclusions

We conclude that IL-6 reduced cell adherence towards laminin and increased MMP-9 production in NPC cells. Our data suggested that EBV LMP1 was able to confer resistance of apoptosis and increased MMP-9 production in NPC cells. When cultured on laminin, TW01 cells expressing the EBV LMP1 (TW0-LMP1) that were treated with IL-6 at 100 pg/ml displayed increased MMP-9 production, up-regulation of bmi-1 oncogene expression and down-regulation of ngx6 tumour suppressor gene expression. These findings implicate the roles of EBV LMP1, laminin and IL-6 in the promotion of invasion and metastasis in NPC.
A Correlation Method in Studying Chemisorption Processes on Uniformly Inhomogeneous Surfaces
Authors: Radeva Greta , Valcheva Eva , Veleva Stefka
Published: October 2010

Chemisorption processes taking place on uniformly inhomogeneous surfaces in the presence of entropic inhomogeneity are examined. A new form of linearity relationship connecting the current rate and the equilibrium constant at definite degrees of surface coverage is derived. The relationship can be applied to complex chemisorption processes when determination of the rate constant is impossible. Linear correlations between the activation energy and the adsorption enthalpy, as well as between the entropy characteristics and pre-exponential factors, are obtained. The complex effect of the energy and entropy factors on the kinetics and the equilibrium is discussed theoretically and verified experimentally. These factors operate through a thermodynamic and a kinetic compensation effect. The present paper illustrates the correlation methods employing experimental results derived from the study of the chemisorption of the optical brighteners Leucophor AP and Tinopal UP onto pulp, of Fe3+ and Cu2+ ions onto fibrous polyampholyte and of hydrolysis-modified polyacrylonitrile (HMP) onto pulp.
Effect of pH on the Clarification of Stevia Rebaudiana Bertoni Extract Using Alginate Beads
Authors: Mahl Cynthia R.A. , de Oliveira Silvia P.D. , da Silva Bruna B. , da Igreja Gabriela , Simões Márcia R. , da Silva Classius F.
Published: October 2010

Stevia rebaudiana Bertoni is plant used for producing a natural sweetener. After extraction from leaves, stevia extract is dark in colour and must be clarified for better acceptance by consumers. Adsorption processes are widely employed in the clarification because they do not use organic solvents. In the present work, the use of alginate beads as an adsorbent was investigated. Experiments were carried out in a batch system in which the aqueous stevia extract was mixed with the alginate beads previously prepared by ionotropic gelation. The effect of pH on the adsorption process was evaluated and the performance of the beads was examined by colorimetric analysis (colour removal, turbidity removal and adsorption of stevia steviol glycosides), as well as by refractive analysis for determining the adsorption of soluble solids. The results showed that the alginate beads were capable of adsorbing both the stevia steviol glycosides and the pigments that colour the extract. The best results were observed at a pH value of 2.0.
Switching Costs, Switching Benefits and Lock-In Effects — The Reregulated Swedish Heat Market
Authors: Hellmer Stefan
Published: October 2010

The paper argues for and defines a locked-in consumer as a consumer that is involuntary locked into one system in spite of an economic incentive to change. A locked-in consumer is therefore not seen as a loyal consumer but instead is assumed to be loyal to a system in spite an obvious economic gain of switching. Being defined as a natural monopoly in its technique, district heating has long been criticized for its eventual abuse of this monopoly position. Therefore, assuming well functioning ex-ante competition, the study calculates switching costs for switching from district heating to pellet burners or heat pumps. The analysis show that there exist relatively substantial benefits of switching from district heating to pellet burning or heat pumps, especially in residential urban areas. With limited available relevant markets, district heating being the only alternative, this negative switching cost cannot be capitalized and represents, in the assumed absence of loyal customers, a lock-in effect. The result indicates that we cannot reject the idea that the district heating plants serving residential areas in Stockholm misuse their dominant position resulting in a reduction of the social welfare.
Energy Consumption of Passenger Land Transport Modes
Authors: Pérez-Martínez Pedro J. , Sorba Iván A.
Published: October 2010

This paper shows how the methodologies used in current practice might lead to an underestimation of energy consumption by different passenger transport modes, and also offers recommendations for improvements to these methodologies. The first recommendation is related to energy consumption rates. The studies reviewed use traditional energy consumption rates based on transportation demand, such as kilowatts-hour per vehicle-kilometre or kilowatts-hour per passenger-kilometre, and include other rates based on transportation supply which might prove useful. Second, energy consumption rates are dependent on factors, and the introduction of homogeneous units which are independent of these factors therefore offers a significant improvement when comparing transport modes. Third, the use of a vehicle energy consumption equation will improve the quality of the assessments. Fourth, we propose that the coefficients which define the energy consumption equation should be broken down to determine market niches and sources for improvements in energy consumption in the vehicle categories.
Towards a Quieter Low Pressure Turbine: Design Characteristics and Prediction Needs
Authors: Nesbitt Eric
Published: October 2010

This article examines Low Pressure Turbine (LPT) noise in modern aircraft and shows how difficult it is to design a quiet LPT. LPT noise has long been neglected in terms of research and prediction capability due to it being considered of lesser importance. Recent developments in LPT design have led to what is termed a “turbine noise storm,” in which the LPT is designed to be cut-off but in the end there is significant LPT noise and little or no ability to reduce it. These developments include the trend toward lower blade counts and solidities. The situation is further hurt due to the inability to predict LPT noise, particularly for the new type of designs. The inability to reduce the LPT noise once the engine and airplane is designed is due to there being no available light-weight high-temperature acoustic-lining technology that can be added to fix a LPT noise problem without a significant penalty. In an attempt to understand what makes some engines' LPT quiet while others are very loud, modern turbine designs are characterized into several LPT noise “classes” and important aspects of each class are shown. Finally, the need for a semi-empirical prediction is discussed including what essential elements this prediction needs to have to be relevant to modern aircraft preliminary design.
A Weak-Scattering Model for Turbine-Tone Haystacking outside the Cone of Silence
Authors: Powles Christopher J. , Tester Brian J. , McAlpine Alan
Published: October 2010

We consider the scattering of sound by turbulence in a jet shear layer. The turbulent, time-varying inhomogeneities in the flow scatter tonal sound fields in such a way as to give spectral broadening, which decreases the level of the incident tone, but increases the broadband level around the frequency of the tone. The scattering process is modelled for observers outside the cone of silence of the jet, using high-frequency asymptotic methods and a weak-scattering assumption. An analytical model for the far-field power spectral density of the scattered field is derived, and the result is compared to experimental data. The model correctly predicts the behaviour of the scattered field as a function of jet velocity and tone frequency.
On the Estimation and Relevance of Internally Generated Turbine Broadband Noise
Authors: Serrano A. , Aparicio J.R. Fernández , Vázquez R.
Published: October 2010

The intention of this paper is quantifying the relevance of the internally generated broadband noise in the overall turbine signature. Results from five cold flow rigs of several low pressure turbines have been used to split the overall turbine noise in the two main sources: tonal and broadband. A comparison between both sources has allowed to determinate the relevance of the broadband noise and its dependence on the design style, operating conditions and turbine application. The methodology to get the broadband noise from a cold flow rig is also discussed and for one specific turbine, the broadband obtained from the rig is compared to engine results to demonstrate that rig noise measurements are enough representative of an engine. Finally, the broadband noise is evaluated at engine level and a turbine source breakdown EPNL is estimated for the three noise critical conditions of Approach, Cutback and Sideline. The main conclusion is that turbine broadband is a relevant source of noise at total aircraft level.
Authoring Tools for KOC — Concepts and Pedagogical Use
Authors: Bravo Germán , Villazón Rafael , Trujillo Augusto , Caviedes Mauricio
Published: October 2010

One of the main problems of teachers aiming to teach the construction techniques used in to build a building is the lack of practical examples to show to their students. In order to be useful, these examples must come from real projects or even better the teachers may take their students to constructions sites, but this latter option is not always available and may be dangerous. To deal with this problem, Los Andes University has committed the construction of a knowledge repository containing information gathered from real projects and semantically described, in order to provide easy access to its content and in the language of people of construction. This project is called KOC, standing for Knowledge Objects of Construction, which uses an ontology to describe semantically the data contained in the repository. Being the pedagogical objective of the project, it is important to provide the teachers with additional tools to generate new knowledge objects, based on existing knowledge objects in the repository. This paper presents three composition tools for KOC: a complex objects composer issued from structured searches, a constructive processes composer and a case study composer, all of them aiming the improvement of learning quality in the technical area of building construction at the architecture and engineering schools. The paper also shows some examples of knowledge objects and how KOC is been used in the courses of the Architecture Department of Los Andes University.
Schematic Systems — Constraining Functions through Processes (and Vice Versa)
Authors: Wurzer Gabriel
Published: October 2010

We propose a novel computer-based design method for planning process-driven buildings which extends the traditional architectural schema to include processes. Each function in the schema can be tied to a process, giving us the ability to find (1.) functions that are not present in any process (2.) processes that lack some of their required functions. As benefit of our approach, we can keep functional program and process models of the building consistent and help bridge the communication gap between process planners and architects, simulating the entered processes as we go along.
Interweaving Grammar: Reconfiguring Vernacular Structure through Parametric Shape Grammar
Authors: Muslimin Rizal
Published: October 2010

This paper re-examines the interweaving method to demonstrate how architectural computation can reinterpret the advantages of this traditional crafting techniques for its geometrical compatibility and rule generativity. Firstly, the technique analyzes and reconfigures load distribution of a traditional interwoven surface to mimic its structural principle. Secondly, from this structural reconfiguration, the study applies parametric shape grammar to define interweaving rules. The rules generate various patterns with rigid local materials that fit the size of human hand. The experiment in this study shows that interweaving grammar can generate ornamental-structural components with three different load distributions, three different segmented materials and in three different spatial dimensions (point, line and plane).
The Impact of Informal Coach Training on the Personal Development of Youth Sport Athletes
Authors: MacDonald Dany J. , Côté Jean , Deakin Janice
Published: October 2010

The role of adults has been outlined as a critical aspect of positive development of young athletes. Youth-sport coaches interact constantly with athletes and hence have the potential to impact significantly on the experiences of youth. Formal coach training has been proposed as a method for helping coaches interact effectively with athletes, but research shows that many coaches learn through experience and interactions with other coaches. The purpose of this study was to determine if coach training offered through the sport program impacts positively on the personal development of youth. Results suggest that athletes who played for coaches that received training through their program reported higher rates of personal and social skills than athletes who played for untrained coaches. Implications for sport programs' administrators are discussed along with recommendations for incorporating positive development principles within a sport environment.
Competitive Swimming Relay Exchange Times: A Descriptive Study
Authors: Siders William
Published: October 2010

Relay exchange times have been proposed as a training target to improve final placing in swimming competition. This study investigated that possibility by analyzing relay exchange times from the 2007 and 2008 USA NCAA Divisions I and II Swimming and Diving Championships. Exchange times from 1292 teams competing in 200 and 400 yard free and medley and 800 yard free relays were studied. The mean team exchange time for non-disqualified teams was .746 ± .232 (standard deviation) sec. Finish places were improved by faster relay exchange times for 205 (15.8% of 1292) teams – exchange times were faster than the next placing team by a time equal to or more than the difference in final times. It is recommended that swimming relay training include strategies to optimize exchange time. However, coaches and competitors must carefully weigh benefits against risks – 3.1% of the teams were disqualified for early relay take-offs.
Interpreting and Implementing the Long Term Athlete Development Model: English Swimming Coaches' Views on the (Swimming) LTAD in Practice
Authors: Lang Melanie , Light Richard
Published: October 2010

The LTAD (Long Term Athlete Development) model has come to represent a sports-wide set of principles that significantly influences national sports policy in England. However, little is known about its impact ‘on the ground.’ This study is concerned with how national sporting bodies have adapted the model to their specific requirements and how local interpretation and implementation of this is operationalized and delivered. Interpretation and implementation of the LTAD model used in English swimming was investigated through interviews with six elite and five non-elite swimming coaches in the north of England. While there were concerns with aspects of the Amateur Swimming Association (ASA) regulations governing competition for age-group swimmers, the major concern expressed by participants was with over-emphasizing volumes of training, leading to the neglect of technique.
Characterisation of Interaction between Combustion Dynamics and Equivalence Ratio Oscillations in a Pressurised Combustor
Authors: van Kampen Jaap F. , Kok Jim B.W.
Published: October 2010

In regular operation, all gas turbine combustors have a significant spontaneous noise level induced by the turbulent high power flame. This noise is characteristic for the operation as it is the result of the interaction between turbulence and combustion. Pressure fluctuations may also be generated by thermoacoustic instabilities induced by amplification by the flame of the acoustic field in the combustor. This paper focuses on the characterisation of the latter process, the combustion dynamics, in a pressurized premixed natural gas combustor. In order to predict the thermo-acoustically unstable operating ranges of modern gas-turbines with the use of an acoustic network model, it is essential to determine accurately the flame transfer function. This transfer function gives the relationship between a perturbation upstream of the flame and its combustion response, leading to acoustic forcing. In this paper, the flame transfer function is obtained by experimental means in a combustor test rig. This test rig was built in the framework of the European DESIRE project, and has the ability to perform thermo-acoustic measurements up to an absolute pressure of 5 bars. The maximum power of the setup is 500 kW.

The paper presents a method to determine the flame transfer function by factorizing it in six subfunctions. Systematically these subfunctions are determined. With the method presented, acoustic measurements on the steady, unperturbed flame and on the unsteady, actively perturbed flame are performed. The effect of pressure is investigated. The steady measurements are used to provide an acousto-combustion finger print of the combustor. In the unsteady measurements, the flame transfer function is reconstructed from the measured acoustic pressures. These flame transfer functions are compared to transfer functions obtained from a numerical experiment in CFD. Good agreement is obtained.
Weedy Rice (Oryza sativa) I. Grain Characteristics and Growth Response to Competition of Weedy Rice Variants from Five Asian Countries
Authors: Chauhan Bhagirath S. , Johnson David E.
Published: October 2010

Weedy rice is a serious weed of cultivated rice in most of the rice-growing areas of the tropics and yet, despite its importance as a weed, limited information is available on its biology in Asia. A study was conducted to determine the seed characteristics and growth response to competition of weedy rice variants from five Asian countries (India [IWR], Malaysia [MWR], Philippines [PWR], Thailand [TWR], and Vietnam [VWR]) when grown alone or with either 4 or 12 cultivated rice (‘IR72’) plants. Seed characteristics including weight, length, width, and presence and length of awn differed between weedy rice variants. PWR had the heaviest seed (25 mg seed−1). Growth of weedy rice plants differed among variants and, generally, VWR grew the fastest. IR72 interference greatly reduced tiller and leaf numbers, leaf area, and shoot biomass of all weedy rice variants. At 8 wk after sowing, for example, shoot biomass of weedy rice variants in competition with 12 IR72 plants was 13 to 30% of that where plants were grown alone. TWR plants were shorter than those of other variants at all levels of crop interference. These results show that there are considerable differences among Asian weedy rice variants and yet, competition from the rice crop greatly suppresses weedy rice growth. This suggests that measures to ensure a competitive crop should be an important component of control strategies.
Interaction of Cultivar, Planting Pattern, and Weed Management Tactics in Peanut
Authors: Place G. T. , Reberg-Horton S. C. , Jordan D. L.
Published: October 2010

Planting peanut in narrow rows for weed control has not been investigated in recently released Virginia market peanut cultivars. Research was conducted in North Carolina from 2007 to 2009 to determine the effect of cultivar, planting pattern, and level of weed management inputs on weed control, peanut yield, and estimated economic return. Experiments consisted of three levels of weed management (clethodim applied POST, cultivation and hand-removal of weeds, and clethodim and appropriate broadleaf herbicides applied POST), three levels of planting pattern (single rows spaced 91 cm apart, standard twin rows spaced 20 cm apart on 91-cm centers, and narrow twin rows consisting of twin rows spaced 20 cm apart on 46-cm centers), and two Virginia cultivars (‘NC 12C’ and ‘VA 98R’). Weed management affected common lambsquarters, common ragweed, eclipta, nodding spurge, pitted morningglory, Texas millet, and yellow nutsedge control, irrespective of cultivar or planting pattern. Cultivar and planting pattern had only minor effects on weed control and interactions of these treatment factors seldom occurred. Weed control achieved with cultivation plus hand-removal was similar to weed management observed with grass and broadleaf herbicide programs. Pod yield did not differ among treatments when broadleaf weeds were the dominant species but did differ when Texas millet was the most prevalent weed. The highest yield with conventional herbicide weed management was in standard twin and narrow twin row planting patterns, although no differences among planting patterns were noted when cultivation and hand-removal were the primary weed management tactics. Differences in estimated economic return were associated with weed species, and interactions of treatment factors varied by year for that parameter.
Hybridization in a Commercial Production Field between Imidazolinone-Resistant Winter Wheat and Jointed Goatgrass (Aegilops cylindrica) Results in Pollen-Mediated Gene Flow ofImi1
Authors: Perez-Jones Alejandro , Martins Bianca A. B. , Mallory-Smith Carol A.
Published: October 2010

Imidazolinone-resistant (IR) winter wheat allows selective control of jointed goatgrass with the herbicide imazamox. However, the spontaneous hybridization between jointed goatgrass and IR winter wheat threatens the value of the IR technology. The objectives of this study were to determine if F1hybrids collected in a commercial production field under IR winter wheat–fallow rotation in Oregon and their first-backcross progeny (BC1) carried theImi1gene and were resistant to imazamox, and to analyze the parentage of F1and BC1plants. The average seed set of the F1spikes was 3.3%, and the average germination of BC1seed was 52%. All F1and BC1plants tested carriedImi1. Jointed goatgrass plant mortality was 100% when treated with imazamox at 0.053 kg ai ha−1, compared to 0% for IR winter wheat and BC1progeny. All F1plants had jointed goatgrass as the maternal parent; whereas, most BC1plants (85.7%) were produced with IR winter wheat as the paternal backcross parent. Although the backcrossing of F1hybrids with jointed goatgrass is very low, it demonstrates the potential for introgression ofImi1from IR winter wheat into jointed goatgrass under natural field conditions.
Reduced Seed Germination after Pappus Removal in the North American Dandelion (Taraxacum officinale; Asteraceae)
Authors: Hale Alison N. , Imfeld Samantha M. , Hart Chloé E. , Gribbins Kevin M. , Yoder Jay A. , Collier Matthew H.
Published: October 2010

This study examined seed ultrastructure in relation to germination of North American dandelion seeds. Based on laboratory rearing observations, it was thought that the design of the pappus acts as a conduit facilitating water entry into the seed. It was hypothesized that seeds without a pappus would yield fewer seedlings and require more time to germinate than seeds with an intact pappus. Seed ultrastructure was investigated using scanning electron microscopy, while relative humidity and fungal association were explored as factors that may confer an advantage to intact seeds. Results indicate that germination for seeds lacking a pappus is 31% lower than control seeds (with an intact pappus) and that the seeds lacking a pappus require more time to germinate. Relative humidity did not differentially affect germination, and while a fungus Cladosporium cladosporioides was recovered internally, its presence neither enhanced germination nor decreased time to germination when tested by antimycotic removal. Electron micrographs revealed that (1) the pappus is hollow and (2) the pericarp of the fruit fuses with and partially encloses the pappus. Fusion of the pappus with the fruit suggests that this structure acts as a device to regulate seed hydration.
Waves and wave overtopping on reservoir structures
Authors: Allsop William , Williamson Tracey , Pullen Tim
Published: October 2010

This paper reviews recent guidance (and associated calculation tools) to predict waves and wave overtopping of reservoir containment structures. It appraises the applicability of recent advances in overtopping analysis intended primarily for coastal structures, but argues that they can equally be applied to the analysis of dams and other reservoir structures. It therefore suggests that a shift in the analysis of dam crest levels to limit wave overtopping discharges may now be timely.
Hydrodynamic pressures behind flexible and rigid dams
Authors: Saleh S , Madabhushi S P G
Published: October 2010

During earthquakes, hydrodynamic pressures are generated by the impounded reservoir on the dam face. The magnitude and distribution of the hydrodynamic pressures vary with factors such as frequency and intensity of earthquake-induced ground motion, depth of impounded reservoir, stiffness of dam and geological conditions. It is difficult to obtain experimental data on hydrodynamic pressures from the field owing to uncertainties associated with earthquake loading. This paper aims at using dynamic centrifuge modelling to measure hydrodynamic pressures behind both relatively stiff and flexible model dams. Comparisons of the experimental data with theoretical hydrodynamic pressures show that Westergaard's equation gives a conservative estimation of hydrodynamic pressures. Comparison with Chopra's method revealed that it underpredicts hydrodynamic pressures for low reservoir depths but gives reasonably good predictions for higher depths of reservoir. It is concluded that dynamic centrifuge modelling may be an effective experimental method to estimate the hydrodynamic pressures acting on a dam.
Performance assessment of precast segmental PSC bridge columns with precast concrete footings
Authors: Kim T.-H. , Park S.-J. , Kim Y.-J. , Shin H.M.
Published: October 2010

The purpose of this study was to investigate the performance of precast segmental prestressed concrete bridge columns with precast concrete footings. The proposed precast concrete footing system is intended to support segmental bridge columns and provides an alternative to current cast-in-place systems, particularly for projects in which a reduced construction time is desired. A model of precast segmental prestressed concrete bridge columns was tested under a constant axial load and a cyclically reversed horizontal load. The computer program, RCAHEST (reinforced concrete analysis in higher evaluation system technology) was used for the analysis of reinforced concrete structures. A bonded or unbonded tendon element is used based on the finite-element method, which can represent the interaction between the tendon and concrete of a prestressed concrete member. A joint element is used to predict the inelastic behaviours of segmental joints with a shear resistance connecting structure. This study documents the testing of precast segmental prestressed concrete bridge columns with precast concrete footings under cyclic loading and presents conclusions and design recommendations based on the experimental and analytical findings. Regarding the implementation of full-scale structures, an investigation of alternative construction details, performance under seismic rather than quasi-static lateral loading and the development of design procedures and guidelines will be carried out in the future.
A simple numerical scheme for evaluating impact-induced compression damage in concrete plate
Authors: Wang Z.L. , Wang J.G. , Yang W.J.
Published: October 2010

This paper focuses on the wave propagation and compression damage in concrete through a plate impact problem. First, the Johnson–Holmquist concrete model is briefed. Then, a cross-format central finite difference scheme is formulated and coded in Fortran 90. After the damage constitutive model is implemented into the code, the stress-wave-induced compression damage in the concrete plate is subsequently simulated. The consistence of the predications between the one-dimensional finite difference code and LS-DYNA is corroborated. Finally, the effects of the magnitude and direction of impact velocity on compression damage are investigated in detail. Numerical results indicate that the proposed methodology is effective and useful. It can be further employed for the protection design of concrete structures against impact loading.
Rational prediction of punching shear strength of slabs reinforced with steel or FRP bars
Authors: Lee J.-H. , Yang J.-M. , Yoon Y.-S.
Published: October 2010

Three two-way slabs reinforced with glass-fibre-reinforced polymer (GFRP) bars were tested, and previous experimental results from two steel-reinforced slabs were used as companion specimens in order to investigate the punching shear behaviour of slabs. The main variables were the slab reinforcement material (steel or GFRP) and the concentration of slab reinforcement around the column. From the experimental results analytical derivation, a rational expression to compute the punching shear strength of two-way concrete slabs was derived. The expression for punching shear strength was further enriched to take into account the elastic modulus of the reinforcement, inclination of the punching crack, flexural reinforcement ratio, size effect and dowel effect. The proposed predictive model was verified by comparison with experimental results, and its accuracy was evaluated through comparisons with various other prediction models. The comparisons confirmed that the proposed model renders fairly accurate and consistent predictions of the punching capacity for either steel- or FRP-reinforced slabs.
Gender Differences in Mental Health Diagnoses Among Iraq and Afghanistan Veterans Enrolled in Veterans Affairs Health Care
Authors: Maguen Shira , Ren Li , Bosch Jeane O. , Marmar Charles R. , Seal Karen H.
Published: October 2010

Objectives. We examined gender differences in sociodemographic, military service, and mental health characteristics among Operation Enduring Freedom (OEF) and Operation Iraqi Freedom (OIF) veterans. We evaluated associations between these sociodemographic and service characteristics and depression and posttraumatic stress disorder (PTSD) diagnoses.

Methods. In a retrospective, cross-sectional study, we used univariate descriptive statistics and log binominal regression analyses of Department of Veterans Affairs (VA) administrative data on 329 049 OEF and OIF veterans seeking VA health care from April 1, 2002, through March 31, 2008.

Results. Female veterans were younger and more likely to be Black and to receive depression diagnoses than were male veterans, who were more frequently diagnosed with PTSD and alcohol use disorders. Older age was associated with a higher prevalence of PTSD and depression diagnoses among women but not among men.

Conclusions. Consideration of gender differences among OEF and OIF veterans seeking health care at the VA will facilitate more targeted prevention and treatment services for these newly returning veterans.
Mental Health Disorders, Psychological Distress, and Suicidality in a Diverse Sample of Lesbian, Gay, Bisexual, and Transgender Youths
Authors: Mustanski Brian S. , Garofalo Robert , Emerson Erin M.
Published: October 2010

Objectives. We examined associations of race/ethnicity, gender, and sexual orientation with mental disorders among lesbian, gay, bisexual, and transgender (LGBT) youths.

Methods. We assessed mental disorders by administering a structured diagnostic interview to a community sample of 246 LGBT youths aged 16 to 20 years. Participants also completed the Brief Symptom Inventory 18 (BSI 18).

Results. One third of participants met criteria for any mental disorder, 17% for conduct disorder, 15% for major depression, and 9% for posttraumatic stress disorder. Anorexia and bulimia were rare. Lifetime suicide attempts were frequent (31%) but less so in the prior 12 months (7%). Few racial/ethnic and gender differences were statistically significant. Bisexually identified youths had lower prevalences of every diagnosis. The BSI 18 had high negative predictive power (90%) and low positive predictive power (25%) for major depression.

Conclusions. LGBT youths had higher prevalences of mental disorder diagnoses than youths in national samples, but were similar to representative samples of urban, racial/ethnic minority youths. Suicide behaviors were similar to those among representative youth samples in the same geographic area. Questionnaires measuring psychological distress may overestimate depression prevalence among this population.
Comparative Analysis of National Legislation in Support of the Revised International Health Regulations: Potential Models for Implementation in the United States
Authors: Katz Rebecca , Kornblet Sarah
Published: October 2010

In 2005, the World Health Organization adopted the revised International Health Regulations, or IHR (2005), to establish obligations for detecting and responding to public health emergencies of international concern.

The success of the IHR (2005) rests on the ability of states to implement the objectives and to execute the regulations in a legal and politically acceptable manner. Implementation of the IHR (2005) may be challenging for federalist nations, where most public health regulatory power lies in local rather than in national governments.

We examine the implementation strategies of 4 nations: Australia, Canada, Germany, and India. The methods currently being considered by these nations for executing the IHR (2005) are potentially applicable models for the United States to consider.
Transforming the Nation's Health: Next Steps in Mental Health Promotion
Authors: Power A. Kathryn
Published: October 2010

The National Research Council and the Institute of Medicine have called for making the healthy mental, emotional, and behavioral development of young people a national priority. The Substance Abuse and Mental Health Services Administration (SAMHSA) in the US Department of Health and Human Services is uniquely positioned to help develop national mental health policies that promote mental health and prevent mental illnesses.

In this article I describe the role of mental health in overall health, I make the case for a public health approach to mental health promotion and mental illness prevention, and I outline a strategy to promote individual, family, and community resilience. I also describe how SAMHSA works to achieve these goals.

Ultimately, true health reform will not succeed without a comprehensive, committed focus on the mental health needs of all Americans.
Change in Level of Positive Mental Health as a Predictor of Future Risk of Mental Illness
Authors: Keyes Corey L. M. , Dhingra Satvinder S. , Simoes Eduardo J.
Published: October 2010

Objectives. We sought to describe the prevalence of mental health and illness, the stability of both diagnoses over time, and whether changes in mental health level predicted mental illness in a cohort group.

Methods. In 2009, we analyzed data from the 1995 and 2005 Midlife in the United States cross-sectional surveys (n = 1723), which measured positive mental health and 12-month mental disorders of major depressive episode, panic, and generalized anxiety disorders.

Results. Population prevalence of any of 3 mental disorders and levels of mental health appeared stable but were dynamic at the individual level. Fifty-two percent of the 17.5% of respondents with any mental illness in 2005 were new cases; one half of those languishing in 1995 improved in 2005, and one half of those flourishing in 1995 declined in 2005. Change in mental health was strongly predictive of prevalence and incidence (operationalized as a new, not necessarily a first, episode) of mental illness in 2005.

Conclusions. Gains in mental health predicted declines in mental illness, supporting the call for public mental health promotion; losses of mental health predicted increases in mental illness, supporting the call for public mental health protection.
The Structure of the Genetic and Environmental Influences on Mental Well-Being
Authors: Keyes Corey L. M. , Myers John M. , Kendler Kenneth S.
Published: October 2010

Objectives. We sought to investigate the structure of the genetic and environmental influences on 3 measures of mental well-being.

Methods. Analyses focused on the subsample of 349 monozygotic and 321 dizygotic same-sex twin pairs from a nationally representative sample of twins who completed self-report measures of emotional, psychological, and social well-being.

Results. The best-fit model contained a common pathway to all 3 measures of well-being, no shared environmental effects, and 1 set of parameters for men and women. Heritability for the latent “mental well-being” factor was high (72%) and best indexed by psychological well-being. Moderate trait-specific genetic effects were seen for emotional and social well-being. Nonshared environmental effects for all measures were mostly trait specific.

Conclusions. Genetic influences on the measures of mental well-being reflect a single, highly heritable genetic factor, although some trait-specific genetic influences were seen for emotional and social well-being. Moderate proportions of environmental influences were also shared, but the majority of unique environment was trait-specific.
Two Endogenous Antiangiogenic Inhibitors, Endostatin and Angiostatin, Demonstrate Biphasic Curves in their Antitumor Profiles
Authors: Javaherian Kashi , Lee Tong-Young , Sjin Robert M. Tjin Tham , Parris George E. , Hlatky Lynn
Published: October 2010

Angiogenesis refers to growth of blood vessels from pre-existing ones. In 1971, Folkman proposed that by choking off the blood supply to tumors, they are starved, leading to their demise. A few years ago, the monoclonal antibody Avastin became the first antiangiogenic biological approved by FDA, for treatment of cancer patients. Two other antiangiogenic endogenous protein fragments were isolated in Folkman's laboratory more than a decade ago. Here, we present a short review of data demonstrating that angiostatin and endostatin display a biphasic antitumor dose-response. This behavior is common among a large number of antiangiogenic agents and the reduced effectiveness of antiangiogenic agents at high dose rates may be due to suppression of growth of new vessels carrying the agent into the critical region around the tumor.