bluuebunny/crossref_metadata_2025 huggingface dataset:
Occurrence of Condensed Tannins in Wheat and Feasibility for Reducing Pasture Bloat
Authors: MacKown Charles T. , Carver Brett F. , Edwards Jeffrey T.
Published: November 2008

Bloat can be a serious problem for ruminant livestock grazing pastures of winter wheat (Triticum aestivum L.) in the southern Great Plains. Tannins in forage can reduce the incidence and severity of bloat. We measured the content and variability of total phenolics and condensed tannins (CT) in forage extracts from wheat varieties and experimental lines (ExpLines) to assess the feasibility of developing improved varieties using conventional breeding methods to give producers a choice to reduce the incidence of bloat. Forage of 16 winter wheat varieties were collected in late fall at the start of grazing. Also, late fall forage samples and regrowth from late fall clipped forage and unclipped growth before jointing were collected for 221 diverse ExpLines and four Check varieties. Among the 16 adapted winter wheat varieties significant differences for the acid‐butanol but not the vanillin CT assay were observed. Among the ExpLines, significant differences in extractable total phenolics were detected (range for all samples collected, 8.9–31.5 mg tannic acid g−1 dry wt.) and for one of the three forage collections using each CT assay. While we observed differences in CT reactive substances among the ExpLines, even the greatest equivalent amounts detected (12 mg quebracho g−1 dry wt. and 0.67 mg epicatechin g−1 dry wt.) are unlikely sufficient to render the forage bloat‐safe. Perhaps those experimental lines with the most abundant CT levels could be used in a selection program to increase the level of CT in wheat forage.
Identification of Soybean Accessions with High Germinability in High‐Temperature Environments
Authors: Smith James R. , Mengistu Alemu , Nelson Randall L. , Paris Robert L.
Published: November 2008

Soybean [Glycine max (L.) Merr.] seed produced in high‐temperature, high‐humidity production environments is prone to have substandard germination. Hardseededness, wrinkled seed coats, and infection by Phomopsis longicolla Hobbs are all known to affect soybean seed germinability. Ancestors of modern U.S. soybean cultivars may lack the necessary variability to impart high germinability to new cultivars without the introgression of new genetic diversity. The purpose of this research was to identify soybean germplasm possessing positive traits affecting high seed germinability for seed produced under high‐temperature environments, such as in the early soybean production system (ESPS) of the midsouthern United States. Seed was produced in the ESPS for 486 U.S. plant introductions (PI), 25 ancestral lines of U.S. cultivars, and four U.S. cultivars at Stoneville, MS, in 2002 and 2003. Standard and accelerated‐aging germination percentages, hardseededness, seed coat wrinkling, and incidence of P. longicolla were estimated for each line. Based on the 2002 and 2003 field data, 42 PIs were selected for further testing, along with three cultivars, in two greenhouse temperature regimes (36° and 42°C) at Stoneville, MS, in 2005. Standard field germinations for the 25 ancestral lines ranged from 26 to 82%. Sixty‐three accessions were identified as having a mean standard field germination of ≥90%, <10% hard seed and P. longicolla infection, and ≤10% wrinkled seed coat. Genotypes with excellent seed traits have now been identified for soybean breeders to use in developing improved cultivars with high seed germinability for use in high‐temperature production environments.
An Improved Method for Simulating Divot Injury on Turfgrass
Authors: Fry Leslie R. , Richardson Michael D. , Karcher Douglas E.
Published: November 2008

Divot recovery has been investigated on many turfgrass species and a number of acceptable methods have been developed to simulate divots for those studies. In an effort to enhance the speed and reliability in simulating divot injuries, a divot‐making machine was developed using a motorized lawn edger equipped with multiple saw blades stacked to a width similar to that of a divot. The uniformity of divots produced with this device was compared to two previously developed devices by cutting 30 divots with each device on three turfgrass species and measuring the width, length, depth, and area of each divot. On all turfgrass species, the device described here produced divots that were either as uniform or more uniform for length, width, depth, and area as the other two devices. In addition, the device can create divots five times faster than the other devices. This improved device should enhance the ability and ease of studying divot injury in the future.
The Utility of Molecular Markers for Barley Net Blotch Resistance across Geographic Regions
Authors: Grewal Tajinder S. , Rossnagel Brian G. , Scoles Graham J.
Published: November 2008

Molecular marker technology shows potential to select and combine favorable alleles via genotypic selection and can be used to develop improved crop cultivars with considerable resource savings. In the present investigation, the utility of molecular markers for net blotch resistance identified in Australian breeding material was investigated for Canadian breeding material. Screening 42 Canadian, Australian, and international barley (Hordeum vulgare L.) lines with 10 Canadian Pyrenophora teres Drechs. isolates identified three lines resistant to all isolates evaluated. Net‐form net blotch isolates were more virulent than spot‐form net blotch isolates. The strong agreement between seedling and adult‐plant reactions indicated that seedling screening could be useful for selection for adult‐plant resistance. Evaluation of the inheritance of resistance in four Australian populations against Canadian P. teres isolates revealed one to three resistance genes, depending on the isolate used. The majority of Australian barley mapping population parents were susceptible to Canadian P. teres isolates, suggesting markers linked to their resistance may not be useful for Canadian breeding; however, some molecular markers identified by Australian workers could be used for Canadian barley breeding. This study demonstrates that the differences in germplasm and fungal pathogen strains used in different countries result in molecular markers that may not be applicable in all breeding programs for that crop.
An Alternative Method for Measuring Plant Available Water in Inorganic Amendments
Authors: Curtis Matthew J. , Claassen Victor P.
Published: November 2008

Inorganic amendments (IA) added to the rootzone of turfgrass are used to increase plant available water (PAW), however conflicting amounts of PAW contents have been reported for some of these amendments. The concept of PAW and the common technique used to estimate PAW in IAs have been reviewed. We hypothesized that hydraulic nonequilibrium in pressure‐plate measurements results in an underestimation of PAW. An alternative standardized method of measuring PAW in coarse‐textured inorganic amendments is proposed using a combination of pressure plates, saturated salt solutions and a dew‐point potentiometer. Water release curves were measured for four IAs (calcined clay, calcined diatomaceous earth, calcined volcanic ash mixed with diatomaceous earth, and zeolite) and their PAW contents determined. Results show that the proposed method provides a more accurate −1500 J kg−1 water content measurement than the pressure‐plate method. Pressure‐plate hydraulic nonequilibrium at −1500 J kg−1 resulted in a 0.002 to 0.012 m3 m−3 underestimation of PAW. The IAs examined in this study did not release appreciable amounts of internally held water until they were exposed to matric potentials more negative than usual in turfgrass management (<−300 J kg−1). The use of a standardized methodology for estimating PAW in IAs, such as the one described in this paper, will help to provide needed consistency and accuracy in information to practitioners.
Effect of Seeding Date, Seeding Rate, and Seed Treatments on Saltgrass Seed Germination and Establishment
Authors: Shahba M. A. , Qian Y. L.
Published: November 2008

Inland saltgrass [Distichlis spicata var. stricta (L.) Greene], native to the western United States, has potential for use as a turfgrass and a revegetation species on saline sites. This study was conducted (i) to evaluate the effect of seeding date, seeding rate, and seed treatments on saltgrass establishment; and (ii) to determine the required accumulative growing degree days (GDD) for saltgrass to establish adequate cover (≥80%) after seeding. Seeding dates were 15 May, 15 June, and 15 July in 2006. Machine scarification and stratification broke saltgrass seed dormancy equally well. Saltgrass seeded in May established adequate coverage (≥80%) in September even using the lowest seeding rate (74 kg ha−1). For plots seeded in June, only the higher seeding rates (123 and 170 kg ha−1) established adequate coverage (≥80%) by the end of growing season. For plots seeded in July, however, even the highest seeding rate failed to establish adequate coverage in September. The accumulated GDD to achieve adequate coverage was 1748, 1663, and 1435 for 74, 123, and 172 kg ha−1 seeding rates, respectively.
Effects of Linkage and Epistasis on Intergeneration Correlations in Self‐Pollinated Species
Authors: Yang Rong‐Cai
Published: November 2008

In breeding for self‐pollinated crop cultivars, early generation testing and selection (EGT) is desirable because it allows for more resources to test superior lines and helps avoid the loss of desirable alleles that would occur if EGT is delayed. However, high intergeneration correlations (IGCs) are required for effective EGT. This study is conducted to determine the effects of linkage and epistasis on IGCs. The covariance between genetic means of lines at early and late selfing generations with both linkage and epistasis is derived. Intergeneration correlations are calculated for different levels of coupling and repulsion linkages and for 10 nonepistatic and epistatic models. Intergeneration correlations are moderate to high in the presence of only additive and dominance effects at unlinked and nonepistatic loci but can be very low (<0.2) in tight repulsion linkages or some allelic and nonallelic effects. Epistasis may mimic or counteract the effects of linkage on changes in IGCs. Thus linkage or epistasis can be an important cause of low IGCs and such genetic causes cannot be changed through testing of more environments. This study points out the need to consider both genetic and nongenetic causes of low IGCs when evaluating the efficiency of EGT in self‐pollinated species.
Mining and Harnessing Natural Variation: A Little MAGIC
Authors: Johal Gurmukh S. , Balint‐Kurti Peter , Weil Clifford F.
Published: November 2008

The success of a breeding program depends on having adequate diversity in the germplasm. However, as advanced breeding stocks and materials are generated, one casualty is the diversity itself. As a result, breeding programs in many crop species have reached a point of diminishing returns and it is feared that unless new diversity is infused into the breeding germplasm, we face catastrophic reductions in crop productivity if the climate turns adverse. Although some scientists favor transgenic approaches, a “back to nature” approach to genetic diversity may prove faster and more effective. Wild and exotic relatives of crop plants hold a wealth of alleles that, if we can find them, can help break yield barriers and enhance tolerance to stresses. Many approaches, based largely on quantitative trait loci genetics, have been proposed and used for this purpose, but most are either highly laborious or discover relevant variation inefficiently. Here, we propose a gene‐centered approach, dubbed MAGIC (mutant‐assisted gene identification and characterization), that uses Mendelian mutants or other genetic variants in a trait of interest as reporters to identify novel genes and variants for that trait. MAGIC is similar to enhancer–suppressor screens, but rather than relying on variation created in the laboratory, it reveals variation created and refined by nature over millions of years of evolution. This approach could be an effective tool for exploring novel variation and a valuable means to harness natural diversity and define genetic networks.
Heritability of Drought Resistance Traits and Correlation of Drought Resistance and Agronomic Traits in Peanut
Authors: Songsri P. , Jogloy S. , Kesmala T. , Vorasoot N. , Akkasaeng C. , Patanothai A. , Holbrook C. C.
Published: November 2008

Inheritance of traits is important for developing effective breeding schemes for improving desired traits. The aims of this study were to estimate the heritabilities (h2) of drought resistance traits and the genotypic (rG) and phenotypic (rP) correlations between drought resistance traits and agronomic traits, and to examine the relationships between drought resistance traits under stressed and nonstressed conditions. The 140 lines in the F4:7 and F4:8 generations from four peanut (Arachis hypogaea L.) crosses were tested under field capacity (FC) and two‐thirds available soil water (2/3 AW) in two field experiments. Data were recorded for specific leaf area (SLA), SPAD chlorophyll meter reading (SCMR), and biomass, pod yield, harvest index, number of mature pods per plant, seed per pod, and seed size. The h2 for biomass, pod yield, DTI (drought tolerance index) (pod yield), DTI (biomass), HI, SLA, and SCMR were high for all tested crosses (0.54–0.98). The rG (−0.61 and −0.66) and rP (−0.61 and −0.66) between SLA and SCMR were strong and negative under 2/3 AW and FC. Under 2/3 AW conditions, SCMR was positively correlated with pod yield and seed size. Compared to SLA, SCMR had higher rG and rP with pod yield, biomass, and other agronomics traits. Significant correlations between FC and 2/3 AW conditions were found for pod yield, biomass, SCMR, and SLA, indicating that these traits could be selected under FC or 2/3 AW conditions. SPAD chlorophyll meter reading, which is easy to measure, is potentially useful as a selection trait for drought resistance because of high h2 and positive correlation with pod yield and agronomic traits.
The Value of p-Value in Biomedical Research
Authors: Panagiotakos Demosthenes B
Published: November 2008

Significance tests and the corresponding p-values play a crucial role in decision making. In this commentary the meaning, interpretation and misinterpretation of p-values is presented. Alternatives for evaluating the reported evidence are also discussed.
Variability in Interbeat Duration Influences Myocardial Contractility in Rat Cardiac Trabeculae
Authors: Torres Carlos A. A , Varian Kenneth D , Janssen Paul M. L
Published: November 2008

There is an intense search for positive inotropic strategies. It is well known that the interbeat duration is a critical determinant of cardiac contractility. Generally, when frequency increases, so does contractile strength. We hypothesize that the beat-to-beat variability at a given heart rate also modulates cardiac contractility. To test this hypothesis, thin, uniform rat cardiac trabeculae were isolated from the right ventricle and stimulated to isometrically contract, alternating between fixed steady state versus variable inter-beat intervals (same total number of beats in each period). Trabeculae were stimulated at 4 Hz with interbeat variation between 20 and 120% (n=17). In a second series of experiments trabeculae were stimulated at 3 different physiologic frequencies with a 40% interbeat variation. Fixed rate response was measured before and after each variable period and average force was calculated. In order to investigate the mechanism underlying the changes in contractility we used iontophoretically loaded bis-fura-2 salt to monitor intracellular calcium transients. We observed no significant change in force at 4 Hz (n=17), and 6 Hz (n=6) between fixed and variable pacing but observed a significant, 10% increase in contractile strength at 8 Hz (from 15.1 to 16.5 mN/mm2, p<0.05, n=6). Our results show that under certain conditions, by simply introducing variation in the beat-to-beat duration without affecting the number of beats per minute, a positive inotropic effect with corresponding changes in the calcium transients can be generated.
On the Use of Air Quality Monitoring Networks for the Evaluation of Nitrogen Oxide Emission Inventories
Authors: Konovalov I.B. , Beekmann M.
Published: November 2008

The usefulness of ground based air quality monitoring data for diagnostics of uncertainties in gridded emission inventories is examined. A general probabilistic procedure for comparison of levels of uncertainties in different emission datasets is developed. It implies the evaluation of the agreement between modeling results obtained with these emission datasets and corresponding measurements. This procedure is applied to the evaluation of different datasets for European gridded nitrogen oxide (NOx) emissions by using the AirBase monitoring data and the CHIMERE chemistry-transport model. Numerical experiments are performed for two different types of spatial distributions of emission uncertainties and five different types of monitors. The results are also generalized for various levels of uncertainties in simulated and measured data. It is found, in particular, that most informative, from the point of view of diagnostics of NOx emission uncertainties, are the measurements of NO2 at rural background sites and measurements of ozone at suburban sites situated in the vicinity of intensive sources of emissions. A more precise conclusion regarding the relative accuracy of two emission datasets can be drawn with a larger number of monitors in a network and a higher accuracy of the model and measurements. For example, with a network of 50 rural background NO2 monitors, the probability of choosing the more certain emission data set is more than 90 percent, if differences in uncertainty of two sets are more than 50 percent. Practical recommendations for designing or evolving surface measurement networks, in light of the study results, are given.
Scenario-Driven Computer-Based Regional Incident Management Training
Authors: Venkatanarayana Ramkumar , Smith Brian L. , Park Hyungjun
Published: November 2008

Incident management is one of the most important functions of a transportation management center (TMC). To efficiently and effectively manage complex regional incidents that affect transportation facilities under the jurisdiction of multiple agencies, TMC operators must be trained appropriately. Recently, a team of universities including the University of Maryland, University of Virginia, and Rensselaer Polytechnic Institute developed a computer-based training tool for regional incident management to be used by the I-95 Corridor Coalition. In its role on the team, the University of Virginia conducted research to support the development of detailed regional incident scenarios to provide content for the computer-based simulation tool. The method created to develop the incident scenarios is presented, with clear examples. Major findings from the research effort include the benefits of rapid prototyping and the usefulness of extensible markup language (XML) for structured content development.
Research to Production
Authors: Smith Brian L. , Griffin Stephen O. , Venkatanarayana Ramkumar
Published: November 2008

The development and delivery of large-scale, complex information systems is difficult, resulting in a low success rate industry-wide. Most production information systems are developed with the use of a top-down approach often called the waterfall model. In developing a complex information system, many variables must be considered and many potential solutions evaluated simultaneously; a linear approach is not conducive to this activity. Also, projects of this scale and complexity can be disruptive and unmanageable in a production environment. The research and development (R&D) environment is better suited to address the challenges presented by these kinds of projects. Development and transfer should not be considered separately, because the former will have a significant effect on the latter. Development in an R&D environment can provide important advantages for ensuring a successful transfer. A real-world case study of transferring an archived data management system from research to production is used to highlight the issues involved and the solutions required to effect the transition. It considers timing and method, emphasizing and detailing important areas of focus for the project partners. Lessons learned from examining this transfer process can benefit researchers, information technology and transportation professionals, and others who are or will be involved in developing information systems.
Information Technology as a Critical Element of the Transportation Infrastructure
Authors: Smith Brian L.
Published: November 2008

Advanced infrastructure systems (AISs) are sensor data–driven control and management systems, which have been developed to improve the performance of society's infrastructure systems. AISs are becoming commonplace in the transportation infrastructure, for example, in traffic operations, structural monitoring, environmental modeling, and especially in the emerging initiative known as vehicle infrastructure integration. Thus, information technology (IT) is fundamentally changing the composition of what is referred to as the transportation infrastructure. Finding sophisticated IT systems serving critical control and management functions in the infrastructure itself also is becoming commonplace. However, in general, the organizational structures of transportation agencies have been established to support IT as a tool to provide administrative and analytic support. To move forward and allow departments of transportation to take full advantage of AISs, it is recommended that agencies establish agencywide groups on IT in infrastructure, create interoperability standards, and better prepare transportation engineers to apply IT.
Determining London Bus Stop Locations by Means of an Automatic Vehicle Location System
Authors: Robinson Stephen P.
Published: November 2008

Automatic vehicle location (AVL) systems are increasingly being introduced across bus networks worldwide to the benefit of passengers and operators. The performance of these systems depends on the quality of the input data, and the accuracy of bus stop locations is among the most important data. Global Positioning System (GPS) devices are used to collect measurements when a bus opens its doors for the purpose of validating bus stop locations. London Buses intends to apply such an approach to validate the locations of all its 19,000 bus stops in London. Three approaches are tried: two based on univariate density estimation and one based on multivariate density estimation. In all cases, a kernel estimator is used. Data collected by the new iBus AVL system along a London bus route are used to determine the best approach. Results suggest that a univariate kernel density estimate with a correction factor to allow for the stop being at the side of the road performs best.
Evaluation and Selection of Adaptive Traffic Control Strategies on Transportation Networks
Authors: Mudigonda Sandeep , Ozbay Kaan , Doshi Harsh
Published: November 2008

With numerous adaptive signal strategies to choose from and the ever-increasing cost of deploying new technologies, transportation professionals need to carefully determine the optimal locations of specific adaptive signal control strategies to maximize their benefits. An interoperable decision support system that not only recommends the best network location for deployment but also provides a seamless data exchange between various data sources will be extremely helpful. The development of a prototype geographic information system– (GIS-) based decision support system (DSS) to address some of these issues is presented. A novel software bridge is implemented to ensure data exchange between the most widely used traffic signal optimization and analysis software, Synchro and the developed GIS-based prototype, the Rutgers Adaptive Signal Control Selection (RASCS) DSS. Integrated modules of this unique GIS-based DSS tool—a macroscopic simulator, a rule-based expert system built up by using various sources, and a benefit–cost analysis module—are then described in detail. Case studies that make use of the developed tool also are presented.
Forecasting Travel Supply and Demand by Modeling Multiscale Urban Environments
Authors: Chaker Walid , Moulin Bernard
Published: November 2008

Traditional microscopic transport simulation approaches usually separate the supply from the demand forecasting by modeling travel demand and the transportation network separately. This approach generally leads to a sizeable calibration task, especially when nested multiscale simulations must be conducted. A generic approach is proposed to model a virtual urban environment in a way that combines data about the population, transportation network, and locations. A scale-independent approach for modeling such an urban environment is presented, along with its application to the Quebec City, Canada, metropolitan region. Some initial results from the TransNetSIM mesoscopic simulator and some computational challenges that were addressed are presented and discussed.
Transformation of Transportation Data Models from Unified Modeling Language to Web Ontology Language
Authors: Zhang Chuanrong , Peng Zhong-Ren , Zhao Tian , Li Weidong
Published: November 2008

Transportation data models traditionally are represented in Unified Modeling Language (UML). UML diagrams are intuitive for understanding transportation concepts and their relationships and thus provide standardized ways to construct transportation data models. Many UML models have been developed for this purpose. However, because UML does not consider semantics, sharing UML data is difficult. Reusing UML diagrams also is difficult. In contrast, web ontology language (OWL) describes the semantics of ontology and thus is good for knowledge sharing and reasoning. OWL data are easier to share and better for performing logical inference. Unfortunately, no automatic method is available to transform data models from UML to OWL. A method to automate the transformation process is presented, using transportation data as a case study. Results indicate that transportation data represented in OWL have many advantages, including facilitated data sharing and inference. They also indicate that although many elements in UML can be transformed to OWL, some do not have OWL counterparts.
Wisconsin Traffic Operations
Authors: Van Hecke Sam , Hedden Chris , Krechmer Dan , Clark Nathan , Szymkowski Todd , Corbin John
Published: November 2008

In July 2006, the Wisconsin Department of Transportation (WisDOT) initiated a Traffic Operations Corridor Sketch-Planning project with the goal of developing a methodology and associated tool that would enable the Bureau of Highway Operations (BHO) to evaluate operational projects in the same manner as traditional infrastructure projects, as well as to integrate operations into the WisDOT planning process. A sketch-planning methodology was developed to achieve these goals with the use of data to drive operations technology recommendations for the WisDOT 2030 multimodal corridor network. This project has resulted in a unique process by which an entire statewide network can be analyzed in terms of operational requirements. These requirements are developed by using not only traditional planning metrics such as safety and traffic volumes and patterns but also operational aspects such as the impacts that special events and weather have on the transportation system. By providing a structured operations data set for integration in long-range planning, the WisDOT BHO has enabled operations strategies to complement, rather than compete with, physical highway improvements. Operations strategies can be a contributing part of the long-range vision for the state through a series of recommendations that are logical and data-driven, as well as communicable and understandable. This report covers the identification of data sources, the development of criteria, the identification of critical thresholds, and the results of the sketch-planning methodology, along with a description of how sketch-planning results are translated into a finalized statewide operations plan.
Intermediate Access to Buffer-Separated Managed Lanes
Authors: Fitzpatrick Kay , Brewer Marcus , Park Eun Sug
Published: November 2008

A Texas Department of Transportation research project developed guidance on intermediate access to and from buffer-separated managed lanes located within general purpose lanes. For intermediate access openings, other communities recommend opening lengths between 1,300 ft and 2,000 ft (396 m to 610 m). While the recommended buffer width is 4 ft (1.2 m) or greater, many sites have a 2- to 3-ft (0.6- to 0.9-m) width. To assist in developing the guidance material, researchers recorded operations at five intermediate access sites. Characteristics measured included where the vehicle entered or left the managed lane (early, within one of two or three equal-distance zones, or late) and the lane of origin for the vehicle. A surprisingly large number of maneuvers (7%) was for vehicles passing a slower-moving vehicle. Approximately 9% of those moving into the high-occupancy vehicle (HOV) lane and 8% of those moving out of the HOV lane crossed the solid white markings (i.e., not in compliance with the pavement markings). The percentage of noncompliance increased to about 15% during those periods with low speeds [less than 40 mph (64 km/h)] or high speeds [greater than 60 mph (96 km/h)]. The percentage of maneuvers in compliance with the pavement markings varied by the length of the intermediate access opening. The compliance rate was greater for the longer access opening length [1,500 ft (457 m)] than for the shorter access opening length [1,160 ft (354 m)].
Introduction of the Dual–System Urban Interchange Design
Authors: Reid Jonathan , Ngai Florence , VanMeter Darryl
Published: November 2008

The new unconventional dual-system urban interchange (DSUI) design has the potential to improve interchange operations and provide additional access capacity to barrier-separated general purpose (GP) and managed-lane systems. Servicing both GP and managed-lane systems at one cross-street interchange location by using conventional interchange design has been viewed as difficult to construct geometrically, and conventional design also introduces undesirable operational issues. The DSUI design includes a system of one-way frontage roads parallel to the freeway facility that is used to manage traffic flows through a series of coordinated signalized intersections. Ramps to and from these frontage roads serve both the GP and managed-lane systems, providing both systems with either direct or indirect interchange access to a common cross street. The DSUI design was developed for a particular interchange location as part of a managed-lane project in Atlanta, Georgia, and has been viewed as a win–win solution by both the corridor design team and community stakeholders. The design has been shown to improve travel time and mobility measures of effectiveness for the corridor compared with other interchange alternatives, and it provides acceptable traffic operations through the project design-year life. To date, the DSUI design concept has been shown to be a viable interchange alternative that could be considered in other managed-lane corridor studies where managed-lane and GP lane access is desired at the same cross street.
High-Occupancy Toll Lanes and Public Transportation
Authors: Turnbull Katherine F.
Published: November 2008

This paper examines the impacts on public transportation services and ridership levels that have resulted from the expansion of high-occupancy vehicle (HOV) lanes to high-occupancy toll (HOT) lanes. The experience with bus services operating on the HOV and HOT lanes on I-15 in San Diego, California; I-394 in Minneapolis, Minnesota; and I-25 in Denver, Colorado is explored. The Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users (SAFETEA-LU) allows increased flexibility for state departments of transportation and other agencies to maximize the use of HOV lanes, including use by tolled single-occupant or lower-occupancy vehicles. As a result, the potential impacts on bus services and ridership levels represent important factors when expanding HOV lane user groups to include tolled vehicles. The three projects provide different perspectives on the potential impacts on public transportation from expanding HOV lanes to include HOT vehicles, as well as the use of transit buses to monitor travel time savings and trip time reliability.
Automated Vehicle Occupancy Verification Systems
Authors: Ungemah David , Lowery John , Wikander John , Goodin Ginger
Published: November 2008

Managed lanes require effective vehicle occupancy enforcement policies and programs to operate successfully. Several semi- and fully automated techniques for determining the number of persons in a moving vehicle, including operator-monitored video cameras and infrared composite imaging, have undergone limited field testing. The technical merits of invehicle and roadside systems for automated vehicle occupancy verification systems have been examined extensively. This paper complements those efforts by providing the policy and legal implications of automated systems for occupancy enforcement. The primary form of automated enforcement technology currently used in the United States is photographic imagery recorded by automated violation detection systems. For moving violations, these systems almost exclusively take the form of red light and speed enforcement, unlike toll evasion, which is typically punishable as an infraction. Principal objections to automated enforcement for occupancy purposes have involved privacy and due process concerns. Under an automated occupancy enforcement tool, the occupancy enforcement regime would likely face the same legal and privacy challenges as automated enforcement cameras and similar devices. This paper examines the current legislation related to automated enforcement practices, as well as an illustration of the arguments against their use. These arguments raise questions about the legality of automated enforcement systems and the perceived invasion of privacy some drivers may associate with such systems. The three primary privacy issues associated with an automated system for occupancy enforcement concern the photographic record of occupants, vehicle infrastructure integration barriers, and the legal definition of a high-occupancy vehicle infraction.
Analysis of Reduction in Effective Capacities of High-Occupancy Vehicle Lanes Related to Traffic Behavior
Authors: Guin Angshuman , Hunter Michael , Guensler Randall
Published: November 2008

Previous research efforts have quantified the capacity of non-barrier-separated, high-occupancy vehicle (HOV) lanes. However, the majority of these efforts have focused on HOV lanes that usually operate well below capacity. In contrast, the I-85 HOV lanes in Atlanta, Georgia, usually operate under constrained flow conditions during morning and afternoon peak periods. This provides an opportunity to assess the relative performance of the HOV lane to the adjacent general-purpose (GP) lanes, which also undergo constrained flow conditions. This paper considers the relationship between the performance of the HOV and GP lanes by examining speed differential effects as a function of congestion on GP lanes. The research provides evidence of a sympathetic reduction in vehicle speeds in the HOV lane. This is likely explained by the safety concerns of the HOV drivers associated with the potential for vehicles using the congested GP lanes to enter the HOV lane, as well as the safety concerns of HOV drivers looking for an acceptable gap to merge into the GP lanes to access a downstream exit ramp.
A Feedback-Based Dynamic Tolling Algorithm for High-Occupancy Toll Lane Operations
Authors: Zhang Guohui , Wang Yinhai , Wei Heng , Yi Ping
Published: November 2008

Dramatically increasing travel demands and insufficient traffic facilities have induced severe traffic congestion. High-occupancy toll (HOT) lane operation has been proposed as one of the most applicable and acceptable countermeasures against freeway congestion. With balanced pricing and vehicle occupancy constraints, HOT lane operations can realize the optimal traffic allocation and enhance overall infrastructure efficiency. However, few previous studies have concentrated on optimal tolling strategies. Two major problems with inferior tolling strategies degrade HOT lane system performance. First, an undersensitive tolling algorithm is incapable of handling the hysteretic properties of traffic systems and may cause severe response delays. Second, oversensitive characteristics of imperfect tolling strategies may cause unfavorable flow fluctuations in HOT and general-purpose lanes that disrupt traffic operations. A new feedback-based tolling algorithm to optimize HOT lane operations addresses these problems. To decompose the calculation complexity, a second-order control scheme is used in this algorithm. On the basis of traffic speed conditions and toll changing patterns, the optimal flow ratio for HOT lane use is calculated by using feedback control theory. The appropriate toll rate is then estimated backward by using the discrete route choice model. This algorithm is simple, effective, and easy to implement. VISSIM-based simulation tests were conducted to examine its practicality and effectiveness. Test results show that the proposed tolling algorithm performed reasonably well in optimizing overall traffic operations of the HOT lane system under various traffic conditions.
Relationship Between Kernel Moisture Content and Water Activity in Different Maturity Stages of Peanut
Authors: Dorner J. W.
Published: November 2008

The water activity (aw) and kernel moisture content (KMC) of individual Florunner cv. peanut kernels representing five different maturity stages were measured during a period of late-season drought stress leading up to normal harvest time. Curves were generated describing the relationship between aw and KMC for yellow 1, yellow 2, orange, brown, and black maturity stages as determined by the peanut hull scrape method. As peanuts matured, the KMC for a given aw decreased. KMC in the most immature yellow 1 stage was extremely variable at higher aw levels, indicative of the rapidly changing composition of kernels at that stage. The variation in KMC at high aw decreased with increasing maturity. Equations to predict KMC for given aw showed that KMC varied greatly among maturity stages, particularly at higher aw. For example, at an aw of 0.99 the predicted KMCs for yellow 1 (least mature) and black (most mature) stages were 62.7 and 30.7%, respectively. The degree of variation among stages decreased as aw decreased in response to drought stress. Because preharvest aflatoxin contamination of peanuts is highly dependent on both the maturity stage of peanuts during periods of late-season drought stress and the resulting aw of kernels, these KMC-aw relationships can be utilized in efforts to breed peanuts for reduced susceptibility to aflatoxin contamination by focusing on genotypes that can maintain higher water activities during such late-season drought periods.
Identification of Peanut Hybrids Using Microsatellite Markers and Horizontal Polyacrylamide Gel Electrophoresis
Authors: Gomez S. M. , Denwar N. N. , Ramasubramanian T. , Simpson Charles E. , Burow G. , Burke J. J. , Puppala N. , Burow M. D.
Published: November 2008

In peanut hybridization, distinguishing inadvertent selfs from the true hybrids may be difficult. In this study, to differentiate between selfs and hybrids, DNA was extracted from leaf tissue of F1 or F2 plants, and SSR markers were amplified and bands separated by a novel submarine horizontal polyacrylamide gel electrophoresis (H-PAGE). By comparing the resulting banding patterns to those of the parents, 70% of the putative hybrids were shown to be true hybrids on the basis of possessing a marker allele from the male parent. The H-PAGE gels gave better band separation and differentiation of selfed progenies than agarose gels, and were compatible with the common horizontal agarose gel units. This method provides a quick assay to distinguish hybrids from inadvertent selfs, and should result in greater efficiency and more effective use of resources in peanut breeding programs.
Impact of Seed Storage Environment on Field Emergence of Peanut (Arachis Hypogaea L.) Cultivars
Authors: Morton B.R. , Tillman B.L. , Gorbet D.W. , Boote K.J.
Published: November 2008

Late-maturing peanut cultivars including DP-1, C-99R, Hull, Georgia-01R, and Florida MDR-98 (Arachis hypogaea L.) have improved resistance to late leaf spot, white mold, and tomato spotted wilt virus. The improved disease resistances offer potential cost savings for farmers. However, poor field emergence resulted in unacceptable plant stands and caused commercial seed companies to stop producing Florida MDR-98, DP-1, and Hull even though germination tests usually showed acceptable germination. Reduced field emergence seldom occurs when seed of these cultivars is grown, harvested, and stored in small batches in research storage facilities. To determine the effect of storage environment, pods of four cultivars were stored in four environments and the seeds were subjected to standard germination tests and immediately followed by field emergence evaluations. Cultivar affected both field emergence and germination. Storage environment affected field emergence, and to a lesser extent, germination (P = 0.0847). Peanut pods stored in a traditional peanut warehouse experienced elevated temperature and relative humidity compared to seeds stored in climate controlled facilities and those seed had reduced field emergence. There was a cultivar by storage environment interaction. Field emergence was maintained when seed was stored where temperature was below 16 C and relative humidity (RH) was less than 70%. This work suggests that seed vigor of the cultivars like DP-1 and Hull deteriorates faster than that of other cultivars when stored in commercial warehouses even though germination tests indicate that the seed should produce satisfactory plant stands.
Peanut (Arachis Hypogaea L.) Cultivar Response to Prohexadione Calcium
Authors: Jordan David L. , Nuti Russell C. , Beam Joshua B. , Lancaster Sarah H. , Lanier James E. , Lassiter Bridget R. , Johnson P. Dewayne
Published: November 2008

Peanut digging efficiency is often reduced due to excessive vine growth. The plant growth regulator prohexadione calcium retards vegetative growth and improves row visibility by inhibiting internode elongation resulting in improved digging efficiency and in some instances increases in pod yield. The objective of this research was to determine the effects of prohexadione calcium on row visibility and pod yield of newly released and commercially available cultivars AT VC-2, Brantley, CHAMPS, Georgia Green, Gregory, Perry, Phillips, NC-V 11, NC 12C, Tamspan 90, and VA 98R and the breeding lines N02006, N01013T, and VT 976133. Although differences in row visibility were noted among cultivars, prohexadione calcium improved row visibility in almost every experiment regardless of cultivar. The cultivars NC 12C and Perry were more responsive to prohexadione calcium in terms of pod yield than NC-V 11 or VA 98R. Response of these cultivars was independent of digging date. In other experiments, prohexadione calcium improved row visibility of the cultivars AT VC-2, Gregory, NC-V 11, Perry, VA 98R, and Wilson, but did not increase yield when compared with non-treated peanut. In a final experiment, prohexadione calcium improved row visibility of the Virginia market type cultivars Brantley, CHAMPS, Gregory, and Phillips and the experimental lines N02006, N01013T, and VT 976133. Row visibility for the experimental line N01013T was improved at 2 of 4 sites by prohexadione calcium. In a final experiment, prohexadione calcium increased row visibility of Georgia Green, Gregory, and Tamspan 90 but did not affect pod yield of these cultivars.
Flavor Profiles of Wild Species-Derived Peanut Breeding Lines
Authors: Tallury S. P. , Pattee H. E. , Isleib T. G. , Stalker H. T.
Published: November 2008

Several diploid wild species of the genus Arachis L. have been used as sources of resistance to common diseases of cultivated peanut (Arachis hypogaea L.). Because flavor is among the most important quality attributes for commercial acceptance of roasted peanuts, sensory attributes of interspecific hybrid derived breeding lines were evaluated to determine if transfer of disease resistance from wild species is associated with concomitant changes in flavor. Sixteen interspecific hybrid derivatives with five diploid species in their ancestries and the commercial flavor standard, NC 7 were evaluated for sensory quality. Significant variation among entries was found for the roasted peanut, sweet, and bitter sensory attributes, but not for the overall contrast between NC 7 and the wild species-derived breeding lines. The variation was either between two groups of wild species-derived breeding lines or within one or both groups. Introduction of disease and pest resistance traits from Arachis species did not result in degradation or improvement of the flavor profile. This suggests that flavor of wild species-derived germplasm will not prevent its use either as parents in peanut breeding programs or as cultivars.
Management of Leaf Spot Diseases of Peanut With Prothioconazole Applied Alone or in Combination With Tebuconazole or Trifloxystrobin
Authors: Culbreath A. K. , Kemerait R. C. , Brenneman T. B.
Published: November 2008

Field experiments were conducted in Tifton and Plains, GA in 2001–2007 to determine the efficacy of prothioconazole on early leaf spot (Cercospora arachidicola) and late leaf spot (Cercosporidium personatum) of peanut (Arachis hypogaea). In five of six experiments, application of one or both rates (0.18 and 0.20 kg ai/ha) of prothioconazole in sprays 3–6 (chlorothalonil at 1.26 kg ai/ha in sprays 1, 2, and 7) provided leaf spot control superior to tebuconazole (0.23 kg ai/ha) in a similar regime, and superior to chlorothalonil at 1.26 kg ai/ha applied full season (seven times) in four of six experiments. In a similar series of six experiments, application of 0.085 kg ai/ha of prothioconazole + 0.17 kg ai/ha of tebuconazole provided better leaf spot control than tebuconazole (0.23 kg ai/ha) applied in regimes similar to those described above. Leaf spot control with prothioconazole + tebuconazole was similar to chlorothalonil applied at 1.26 kg ai/ha full season in five of eight experiments, but was less effective in the remaining three experiments. Fungicide effects on yield were inconsistent, but in all experiments, yield response with either rate of prothioconazole was similar to or greater than that obtained with 0.23 kg ai/ha tebuconazole on the same schedule. In a third series of four experiments, full-season (seven sprays) application of mixtures of prothioconazole at 0.063 kg ai/ha with trifloxystrobin at 0.063 kg ai/ha gave similar or better leaf spot control than chlorothalonil full season.