bluuebunny/crossref_metadata_2025_split huggingface dataset:
Security risk assessments in public transport networks
Authors: Sánchez M M 
Published: June 2011

This article presents a research that was aimed at developing a better understanding of current threats and how to conduct risk assessments in public transport networks by following generic guidelines that can be adapted according to each organization's needs. The aim is to facilitate the task of identifying threats and conduct a vulnerability analysis to help decision makers to prioritize resources in a systematic manner and consequently increase resilience. This article also highlights the main benefits and constraints of performing risk assessments and how the results of risk assessments can be used as a solid foundation for a structured, analytically clear, and systematic approach to security planning for a public transport network. In addition to the summary of the above research, a questionnaire was distributed among three main operators in Europe to gain more insight about the current state of the art in risk assessments in public transport systems. Key aspects of the research can be found presented as Guidelines for Users in the accompanying papers by Barr and Luyten.
Comparison of injectors for compression ignition of natural gas with entrained diesel
Authors: Brown B S , Laforet C A , Rogak S N , Munsh S R 
Published: June 2011

New fuel injector prototypes for heavy-duty engines have been developed to use direct-injection natural gas with small amounts of entrained diesel as an ignition promoter. This ‘co-injection’ is different from other dual-fuel engine systems, where diesel and gas are introduced separately. Two co-injectors were compared with a Westport HPDI injector that injects diesel and gas through separate systems into the cylinder. All injectors have identical gas-nozzle geometry and inject fuel into the cylinder near top-dead-centre, but differ in the manner of introducing the diesel. Both co-injectors introduce diesel into the gas plenum before the gas needle is actuated, causing a two-phase gas-blast injection. The first co-injector (‘B’) injects the diesel with relatively high velocity into the gas plenum, which probably disperses it over a large volume inside the injector. The second prototype (‘CS’) introduces the diesel at very low velocity so that it may remain near the needle seat prior to injection. The injectors were tested in a 2.5-litre single-cylinder engine with 17:1 compression ratio. Load varied from 6 to 13 bar gross indicated mean effective pressure. Temperature-controlled exhaust-gas recirculation of 0 or 30 per cent was used. Co-injection of natural gas and diesel can increase the ignition delay relative to the HPDI system (which uses a pure diesel pilot injection). The HPDI and CS injectors required 7–15 per cent diesel fuelling (by energy), while B required 9 to 20 per cent diesel fuelling. All injectors yielded the same fuel economy (within 2 per cent). However, premixed diesel, gas, and air can burn rapidly enough to produce knock. Knock was typically inaudible (below 3 bar intensity) and greatly reduced for conditions with exhaust-gas recirculation. With co-injector CS, all gaseous emissions could be brought very close to those of the HDPIJ36 injector, but co-injector B resulted in high hydrocarbon and CO emissions at low load. Particulate emissions from the co-injectors were slightly lower than for the J36 injector, possibly due to more fuel/air premixing prior to ignition.
Distribution of Nutrients Among Soil–Plant Pools in ‘Tifton 85’ Bermudagrass Pastures Grazed at Different Intensities
Authors: Liu Kesi , Sollenberger Lynn E. , Silveira Maria L. , Vendramini João M.B. , Newman Yoana C. 
Published: June 2011

ABSTRACTChoice of grazing intensity (i.e., stocking rate or grazed sward height) has an important role in the functioning of grassland ecosystems; however, the effect of grazing intensity on size and relative importance of various grassland nutrient pools is not well understood. The objective of this 2‐yr study, conducted on soils from the Plummer and Sparr series, was to determine the effect of stubble height after grazing (SH) on nutrient distribution among plant and soil (0‐ to 20‐cm depth) nutrient pools in ‘Tifton 85’ bermudagrass (Cynodon spp.) pastures. Swards were stocked rotationally and grazed every 28 d to SH of 8, 16, and 24 cm. Green herbage, plant litter, and root–rhizome pool masses increased as SH increased. Plant nutrient concentrations (g kg−1) were relatively unresponsive to SH, but soil C and N concentrations increased by 23 and 34%, respectively, as SH increased. Nutrient content (kg ha−1) of all plant pools increased as SH increased, mainly a function of increasing pool mass. Soil pool P and K content (Mehlich‐1) were not affected by SH, but total C (17%) and N (27%) content increased with taller SH. The soil pool to 20 cm contained approximately 40, 85, 90, and 80% of K, P, N, and C, respectively. Reducing grazing intensity of Tifton 85 bermudagrass pastures appears to be a viable strategy for increasing nutrient content of most plant pools and for increasing the N and C content of the soil pool.
Divergent Mass Selection for Leaf Chlorophyll Content Measured Using Chlorophyll Meter Readings in a Maize Composite Population
Authors: Korkovelos A. E. , Goulas C. K. 
Published: June 2011

ABSTRACTLeaf chlorophyll content is correlated with photosynthetic activity indicators and leaf nitrogen concentration. Three cycles of divergent mass selection for chlorophyll content were performed to estimate heritability, response to selection, and correlated changes in grain yield for these traits in a synthetic maize (Zea mays L.) population. Selection for high and low chlorophyll content was performed in the field using the SPAD chlorophyll meter, and response to selection was measured in field evaluations of the C0, C1, C2, and C3 populations. The divergent selection responses cycle−1 were 1.2 SPAD unit increase versus 0.2 decrease at anthesis and 0.9 increase versus 0.9 decrease at grain‐filling period relative to the base average of 55.9 and 53.5, respectively. The C3 high and low selections showed significant differences in chlorophyll content at anthesis and grain filling stages, but no significant selection indirect response was detected for grain yield. Thus, our data indicate that leaf chlorophyll content is heritable and that it can be manipulated through conventional breeding methodology. Additional cycles of chlorophyll content selection are needed to determine if chlorophyll content will be useful as an indirect selection criterion for yield improvement.
Regrowth Dynamics of ‘Tifton 85’ Bermudagrass as Affected by Nitrogen Fertilization
Authors: Alderman PD. , Boote KJ. , Sollenberger LE. 
Published: June 2011

ABSTRACT‘Tifton 85’ bermudagrass (Cynodon spp.) has been widely adopted as a forage and hay crop and is being considered as a cellulosic ethanol feedstock. The objective of this study was to evaluate the effects of N fertilization rate on Tifton 85 regrowth dynamics. A field study was conducted near Gainesville, FL, on established Tifton 85 in 2006 and 2007. The treatments were N rates of 0, 45, 90, and 135 kg N ha−1 regrowth period−1. Tissue mass, leaf:stem ratio, and tiller number and mass were measured weekly during 28‐d regrowth periods. Leaf mass followed logistic time trends with the upper asymptote varying between 50 and 225 g m−2 depending on N rate and season (summer and autumn). Stem mass lagged behind leaf mass for 7 to 14 d, subsequently following linear or quadratic time trends to reach between 75 and 300 g m−2 by 28 d. Increasing N rate from 0 to 135 kg ha−1 period−1 increased tiller mass at 28 d from 1.5 to 3 g tiller−1 in summer and 1 to 1.5 g tiller−1 in autumn. Leaf:stem ratio increased to 1.0 within 14 to 21 d, followed by a subsequent decrease. Rhizome and root mass were not affected by N fertilization. Increasing N rate primarily affected mass and proportion of above‐ground plant parts, with little effect on mass of below‐ground parts. Nitrogen nutrition index values were similar whether calculated from samples taken to a 10‐cm stubble height or from samples taken to the soil surface. Regrowth was not enhanced by N rate beyond 90 kg N ha−1 regrowth period−1.
Soybean Plastidal Omega‐3 Fatty Acid Desaturase Genes GmFAD7 and GmFAD8: Structure and Expression
Authors: Upchurch Robert G. , Ramirez Martha E. 
Published: June 2011

ABSTRACTWe characterized soybean [Glycine max (L.) Merr.] FAD7 and FAD8 gene structure and expression responses to temperature and pathogen stress to compare and contrast these features to those reported for higher plant plastidal omega‐3 (ω‐3) desaturases. We found that the genomic structure and deduced amino acid sequence of soybean FAD7 and FAD8 are similar to other higher plant plastidal ω‐3 desaturases: eight exons and seven introns, predicted proteins of 453 amino acid residues containing three conserved histidine motifs, amino terminal chloroplast transit peptides, and molecular masses of 51.3 and 51.4 kDa, respectively. GmFAD7 has 76% amino acid sequence identity to GmFAD8. Two complete copies of GmFAD7, one on chromosome 18 and one on chromosome 7, and two complete copies of GmFAD8, one on chromosome 3 and one on chromosome 1 of the ‘Williams 82’ soybean genome, were found with strong sequence similarity to GmFAD7 and GmFAD8 of cultivar Dare. Dare GmFAD7 transcript expression in leaves remained at a relatively low level and was unaffected by any of the temperature treatments we imposed, but GmFAD8 transcript accumulation was sharply upregulated by a cool temperature (20/16°C day/night) after a 12 h exposure and total linolenic acid as a percent of total leaf fatty acids increased from 60 to about 68% after 48 h at the cool temperature. Inoculation of soybean leaves with the fungal pathogen Cercospora kikuchii differentially upregulated the level of GmFAD7 transcripts to twice that of GmFAD8 by 12 h postinoculation. The response of soybean foliar FAD8 expression and linolenic acid levels to cool temperature was similar to observations in other plants. On the other hand, despite increased soybean FAD7 expression in response to foliar pathogen stress the expected associated increase in foliar linolenic acid was not detected.
Maturity and Regrowth Influences on Quality of Caucasian Bluestem Hay
Authors: Burns J.C. 
Published: June 2011

ABSTRACTCaucasian bluestem [CBS; Bothriochloa caucasica (Trin.) C.E. Hubbard ‘Caucasian’] appears adapted to the mid‐Atlantic region. Three experiments, one with sheep and two with steers, were conducted to assess hay quality. In Experiment (Exp.) 1, initial growth was cut at early boot, anthesis, and postanthesis and regrowth cut at early boot and anthesis (five treatments) and evaluated by wether sheep. All treatments, except regrowth anthesis were also evaluated in a preliminary experiment with steers. In Exp. 2, regrowth was cut at the same three initial growth stages as in Exp. 1 and evaluated by steers. Sheep readily ate CBS hay, consuming 1.88 kg 100 kg−1 body weight (BW) when the hay was cut at early boot, with apparent dry matter digestion (DMD) of 647 g kg−1. Intake decreased linearly by postanthesis to 1.45 kg 100 kg−1 BW with DMD of 548 g kg−1. Steers also readily ate early‐boot CBS hay, averaging 2.49 kg 100 kg−1 BW with DMD of 661 g kg−1. Intake decreased linearly by postanthesis to 1.48 kg 100 kg−1 BW with a DMD of 589 g kg−1. Sheep and steer intake was well correlated (r = 0.951; P = 0.05) as was DMD (r = 0.939; P = 0.06). In Exp. 2, steers readily consumed regrowth hay, averaging 2.73 kg 100 kg−1 BW for the early‐boot cut with a DMD of 670 g kg−1. Intake declined linearly by postanthesis to 1.57 kg 100 kg−1 BW with a DMD of 517 g kg−1. Hays of CBS can provide desirable quality for animal production systems if it is cut by the early‐boot stage in the mid‐Atlantic region of the United States.
Instability of the Greens‐Type Phenotype in Poa annua L.
Authors: La Mantia Jonathan M. , Huff David R. 
Published: June 2011

ABSTRACTThe turfgrass species Poa annua L. is most prevalent as an invasive, annual weed in managed turfs. Conversely, the dwarf perennial greens‐type biotype produces a high turf quality with great utility to the golf‐course industry. In the past 60 yr, several attempts have been made to breed a commercial cultivar of the greens‐type biotype with little sustained success. Here, we characterize the morphological traits of the greens‐type phenotype and investigate its inheritance and stability through genetic crosses. The results indicate that the greens‐type phenotype links single‐branching inflorescences with reductions in culm length, tiller length, leaf length, and panicle length to a single genetic mechanism. However, in advanced‐generation progeny, the segregation of the greens‐type phenotype does not conform to the disomic single‐gene inheritance model. Tetrasomic inheritance, gene complementation, and quantitative inheritance models are also presented. These results, along with the observation of somatic reversions, suggest that the greens‐type phenotype is unstable and may be regulated by an epigenetic mechanism.
Environment and Hybrid Influences on Rapid‐Visco‐Analysis Flour Properties of Food‐Grade Grain Sorghum
Authors: Griess Joni K. , Mason Stephen C. , Jackson David S. , Galusha Tomie D. , Pedersen Jeffrey F. , Yaseen Muhammad 
Published: June 2011

ABSTRACTGrain processors would benefit from information about the production environment and the influences of the sorghum [Sorghum bicolor (L.) Moench] hybrid on food‐grade flour properties. The objective of this study was to determine the effects of environment and hybrid on rapid‐visco‐analysis (RVA) flour properties of commercially available food‐grade sorghum. A randomized complete block experiment was planted in 12 environments, which included the 2004 and 2005 growing seasons and irrigated and dryland water regimes in eastern, central, and west central Nebraska, and a dryland, low‐N environment in eastern Nebraska. The environment accounted for 71–85% of the total variation in RVA parameters, while the hybrid accounted for 11–23% and the environment‐by‐hybrid interaction, 1–3%. Unfortunately, the results of this experiment suggest that it is difficult to predict the effect that environment will have on resulting sorghum‐flour parameters. Although of secondary importance in terms of total variation in sorghum‐flour RVA properties, the choice of hybrid predictably and significantly contributes to sorghum‐starch viscosity properties. Food‐grade hybrids were grouped based on viscosity properties into those best suited for dry‐mill and alkaline‐cooked products (Asgrow Orbit; Sorghum Partners NK1486) and those best suited for porridge, consumable alcohol, and ethanol production (Kelly Green Seeds KG6902; NC+ Hybrids 7W92; Asgrow Eclipse; and Fontanelle W‐1000). These results were consistent with those previously reported for grain density.
Ensuring Genetic Purity of Pigeonpea Hybrids by Incorporating a Naked‐Eye Polymorphic Marker in A and B Lines
Authors: Saxena K. B. , Vales M. I. , Kumar R. V. , Sultana R. , Srivastava R. K. 
Published: June 2011

ABSTRACTTo enhance the productivity of pigeonpea [Cajanus cajan (L.) Millspaugh] a hybrid breeding technology, based on the cytoplasmic nuclear male‐sterility (CMS) system and partial natural outcrossing, is currently been used. However, there are difficulties to maintain genetic purity of the hybrids and their parents. The incorporation of an easily identifiable morphological marker (naked eye polymorphism [NEP]) could be used to determine seed purity. The morphological marker selected for this study, obcordate leaf, is not present in cultivated pigeonpea; it is inherited as a single recessive gene and can be observed soon after planting (approx. 6 wk). To incorporate the obcordate leaf shape into hybrid parents, the trait was transferred from the germplasm accession ICP 5529 into male‐sterile (A lines) and the corresponding maintainers (B lines). The hybrids derived from crosses involving obcordate leaf A lines and normal leaf fertility restorers (R lines) were fully fertile and had normal lanceolate leaves; thus the difference between A line and hybrids was clear. The use of obcordate leaf as a NEP marker in pigeonpea would contribute to preserve parental line purity and confirm hybrid status.
A solution of an open problem concerning Lagrangian mean-type mappings
Authors: Głazowska Dorota 
Published: June 2011

Abstract
The problem of invariance of the geometric mean in the class of Lagrangian means was considered in [Głazowska D., Matkowski J., An invariance of geometric mean with respect to Lagrangian means, J. Math. Anal. Appl., 2007, 331(2), 1187–1199], where some necessary conditions for the generators of Lagrangian means have been established. The question if all necessary conditions are also sufficient remained open. In this paper we solve this problem.
Modern approaches to modeling user requirements on resource and task allocation in hierarchical computational grids
Authors: Kołodziej Joanna , Xhafa Fatos 
Published: June 2011

Modern approaches to modeling user requirements on resource and task allocation in hierarchical computational grids
Tasks scheduling and resource allocation are among crucial issues in any large scale distributed system, including Computational Grids (CGs). These issues are commonly investigated using traditional computational models and resolution methods that yield near-optimal scheduling strategies. One drawback of such approaches is that they cannot effectively tackle the complex nature of CGs. On the one hand, such systems account for many administrative domains with their own access policies, user privileges, etc. On the other, CGs have hierarchical nature and therefore any computational model should be able to effectively express the hierarchical architecture in the optimization model. Recently, researchers have been investigating the use of game theory for modeling user requirements regarding task and resource allocation in grid scheduling problems. In this paper we present two general non-cooperative game approaches, namely, the symmetric non-zero sum game and the asymmetric Stackelberg game for modeling grid user behavior defined as user requirements. In our game-theoretic approaches we are able to cast new requirements arising in allocation problems, such as asymmetric users relations, security and reliability restrictions in CGs. For solving the games, we designed and implemented GA-based hybrid schedulers for approximating the equilibrium points for both games. The proposed hybrid resolution methods are experimentally evaluated through the grid simulator under heterogeneity, and large-scale and dynamics conditions. The relative performance of the schedulers is measured in terms of the makespan and flowtime metrics. The experimental analysis showed high efficiency of meta-heuristics in solving the game-based models, especially in the case of an additional cost of secure task scheduling to be paid by the users.
Resource and service discovery in SOAs: A P2P oriented semantic approach
Authors: Di Modica Giuseppe , Tomarchio Orazio , Vita Lorenzo 
Published: June 2011

Resource and service discovery in SOAs: A P2P oriented semantic approachAn intense standardization process is favouring the convergence of grids and Service Oriented Architectures (SOAs). One of the benefits of such technological convergence is that grid resources and applications can be virtualized by services and offered through the SOA paradigm. In the broad and interoperable scenarios enabled by the SOA, involving the participation of several grid infrastructures across many administrative domains, service discovery can be a serious issue. In this paper we present a P2P-based infrastructure that leverages semantic technologies to support a scalable and accurate service discovery process. The key concept of the presented idea is the creation of an overlay network organized in several semantic groups of peers, each specialized in answering queries pertaining to specific applicative domains. Groups are formed by clustering together peers offering services that are semantically related. The architecture details of the proposed solution are presented. A system prototype has also been implemented and validated through a case study deployed on the PlanetLab testbed.
P2P video streaming combining SVC and MDC
Authors: de Asís López-Fuentes Francisco 
Published: June 2011

P2P video streaming combining SVC and MDC
In this paper we propose and evaluate a combined SVC-MDC (Scalable Video Coding & Multiple Description Video Coding) video coding scheme for Peer-to-Peer (P2P) video multicast. The proposed scheme is based on a full cooperation established between the peer sites, which contribute their upload capacity during video distribution. The source site splits the video content into many small blocks and assigns each block to a single peer for redistribution. Our solution is implemented in a fully meshed P2P network in which peers are connected to each other via UDP (User Datagram Protocol) links. The video content is encoded by using the Scalable Video Coding (SVC) method. We present a flow control mechanism that allows us to optimize dynamically the overall throughput and to automatically adjust video quality for each peer. Thus, peers with different upload capacity receive different video quality. We also combine the SVC method with Multiple Description Coding (MDC) to alleviate the packet loss problem. We implemented and tested this approach in the PlanetLab infrastructure. The obtained results show that our solution achieves good performance and remarkable video quality in the presence of packet loss.
Random perturbation of the projected variable metric method for nonsmooth nonconvex optimization problems with linear constraints
Authors: El Mouatasim Abdelkrim , Ellaia Rachid , de Cursi Eduardo 
Published: June 2011

Random perturbation of the projected variable metric method for nonsmooth nonconvex optimization problems with linear constraintsWe present a random perturbation of the projected variable metric method for solving linearly constrained nonsmooth (i.e., nondifferentiable) nonconvex optimization problems, and we establish the convergence to a global minimum for a locally Lipschitz continuous objective function which may be nondifferentiable on a countable set of points. Numerical results show the effectiveness of the proposed approach.
Akt-Mediated Proinflammatory Response of Mononuclear Phagocytes Infected with Burkholderia cenocepacia Occurs by a Novel GSK3β-Dependent, IκB Kinase-Independent Mechanism
Authors: Cremer Thomas J. , Shah Prexy , Cormet-Boyaka Estelle , Valvano Miguel A. , Butchar Jonathan P. , Tridandapani Susheela 
Published: June 2011

Abstract
The environmental bacterium Burkholderia cenocepacia causes opportunistic lung infections in immunocompromised individuals, particularly in patients with cystic fibrosis. Infections in these patients are associated with exacerbated inflammation leading to rapid decay of lung function, and in some cases resulting in cepacia syndrome, which is characterized by a fatal acute necrotizing pneumonia and sepsis. B. cenocepacia can survive intracellularly in macrophages by altering the maturation of the phagosome, but very little is known on macrophage responses to the intracellular infection. In this study, we have examined the role of the PI3K/Akt signaling pathway in B. cenocepacia-infected monocytes and macrophages. We show that PI3K/Akt activity was required for NF-κB activity and the secretion of proinflammatory cytokines during infection with B. cenocepacia. In contrast to previous observations in epithelial cells infected with other Gram-negative bacteria, Akt did not enhance IκB kinase or NF-κB p65 phosphorylation, but rather inhibited GSK3β, a negative regulator of NF-κB transcriptional activity. This novel mechanism of modulation of NF-κB activity may provide a unique therapeutic target for controlling excessive inflammation upon B. cenocepacia infection.