An Annotated Checklist of the Crayfishes (Decapoda: Cambaridae) of Arkansas

Prior to the present study, 56 species with 3 additional subspecies for a total of 59 different taxa of crayfishes were recognized from Arkansas. We add a single species (Carmel Crayfish, Fallicambarus schusteri) to that list, subtract a documented synonym (Procambarus ferrugenius = Procambarus liberorum), update the classification to better reflect recent phylogenetic insights, and provide an updated annotated checklist of the 59 crayfish taxa of presently known from the state. There are 8 endemic species in Arkansas, including the Bayou Bodcau Crayfish (Bouchardina robisoni), Boston Mountains Crayfish (Cambarus causeyi), Hell Creek Cave Crayfish (C. zophonastes), Jefferson County Crayfish (Creaserinus gilpini), Ouachita Burrowing Crayfish (Fallicambarus harpi), Slenderwrist Burrowing Crayfish (F. petilicarpus), Saline Burrowing Crayfish (F. strawni), and Redspotted Stream Crayfish (Faxonius acares). There are also 2 federally endangered species, the Benton County Cave Crayfish (Cambarus aculabrum) and the Hell Creek Cave Crayfish (C. zophonastes) that inhabit Arkansas karst habitat. We expect that additional species will be included in the list with further DNA analyses

The Role Of Simulation In The Test And Evaluation Of A Man In The Loop Weapon System

The Department of Defense has attempted to use recent advances in modeling and simulation to improve the acquisition process for weapons systems. This Simulation Based Acquisition brought advances in the process, but considerable disagreement remains over the universal applicability of this approach. This paper focuses on the challenges of applying modeling and simulation to the Test and Evaluation of a weapon system with significant Pilot-Vehicle interface concerns. The Standoff Land Attack Missile Expanded Response (SLAM ER) is an aircraft-launched missile with GPS/INS guidance for navigation to the target area and Man In The Loop (MITL) control in the terminal phase. The MITL control is conducted through a two way video and control data link which transmits infrared video from the missile seeker to the control aircraft and guidance update commands from the pilot back to the missile. After initial fielding of the weapon system, two preplanned product improvement programs were begun to add both an Automatic Target Acquisition (ATA) functionality to aid in pilot target identification as well as a capability to engage moving targets at sea (ASuW). Both Software in the Loop and Hardware in the Loop simulations were available for the testing of both these SLAM ER improvements. This paper focuses on the utility of this simulation support in the Test and Evaluation prior to delivery to the operational users. Though the management issues of cost and schedule can be large drivers in the use of modeling and simulation, this paper will focus on the performance aspect of weapon system evaluation. Through the course of both the ATA and ASuW evaluations, simulation was able to provide very limited contributions to evaluations of system performance when MITL control was a concern. Simulation was useful in providing data on easily quantifiable parameters, such as seeker scan rates. However, flight tests with a physical prototype provided the only effective data when subjective measures such as pilot workload and pilot target identification were a concern. The simulators available did not effectively replicate the pilot interface or workload environment to the level required for valid MITL data. Only when an issue with the pilot interface was easily defined in quantifiable engineering data was simulation useful in identifying a possible solution – one that had to be further evaluated in subsequent flight testing. As the quality of models and simulations continue to improve with advances in computing, modeling of the pilot vehicle interfaces may improve in the future. Until that time, management controls will be essential to correct application of modeling and simulation in areas where MITL is a concern. The development of models and simulations should begin early in the acquisition effort with robust verification and validation devoted to the pilot interface. Early identification of the areas in which simulations can contribute to the MITL evaluation effort as well as recognition of the limitations of models and simulations. Finally, the validated simulations should be viewed as an enhancement to the evaluation effort with live testing of the physical prototype forming the basis of the MITL evaluation, particularly when the system approaches the final phases of Developmental Testing and prepares for Operational Testing

Structure-function studies of the saccharomyces cerevisiae pheromone receptor, ste2p, using novel α-factor analogs

G-protein coupled receptors (GPCRs) are heptahelical membrane proteins that allow cells to sense and respond to a variety of environmental stimuli. Study of GPCRS has begun to elucidate their important role in human disease and has allowed for the development of a number of clinical treatments. The yeast Saccharomyces cerevisiae which uses peptide pheromones and GPCRs to mediate sexual reproduction between haploid cells presents a model system for the study of GPCRS. The studies presented here detail the use of novel peptide analogs to investigate the structure-function relationship between the Ste2p receptor and its ligand, the α-factor pheromone. Characterization of a gamut of α-factor analogs resulted in the identification of several analogs with biological activity and sub-micromolar binding affinity (Kd) identifying them as good candidates for use in photoaffinity labeling studies to map the a-factor binding site in the Ste2p receptor. Photoaffinity labeling with the analog [Bpa¹ Y³ (1251) R7 Nle12F13] α-factor and subsequent receptor fragmentation showed that position one of the α-factor peptide crosslinked to a fragment of the receptor from amino acid 190 to 294. Formation of a dimeric α-factor molecule by covalent attachment of the epsilon amines of Lys7 via an aminohexanoic acid bridge resulted in a ligand which showed specific binding to the Ste2p receptor and the ability to activate the pheromone signal cascade. The binding affinity and biological activity of this α- factor dimer suggest that the Lys7 residue in α-factor is relatively exposed to solvent and not buried into the receptor. These findings support the current model of the structure of α-factor when it is bound to the Ste2p receptor. Further characterization of a novel class of α-factor analogs termed synergist has revealed that these ligands do not enhance biological activity by modulating the rates of association or dissociation of agonists to the Ste2p receptor. Furthermore, the synergists do not increase the total amount of agonist binding to Ste2p since the total amount of [³H] α-factor associated to Ste2p does not change in the presence or absence of synergist. The new information from these studies has allowed for several models of synergist action to be proposed

The Present Status of the Transmissibility of Bovine Tuberculosisas Illustrated by Infants and Young Children.

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Safehold Attitude Determination Approach for GPM

Spacecraft sating designs generally have minimal goals with loose pointing requirements. Safe pointing orientations for three-axis stabilized spacecraft are usually chosen to put the spacecraft into a thermally safe and power-positive orientation. In addition, safe mode designs are required to be simple and reliable. This simplicity lends itself to the usage of analog sun sensors, because digital sun sensors will add unwanted complexity to the safe hold mode. The Global Precipitation Measurement (GPM) Mission Core Observatory will launch into lower earth orbit (LEO) at an inclination of 65 degrees. The GPM instrument suite consists of an active radar system and a passive microwave imager to provide the next-generation global observations of rain and snow. The complexity and precision of these instruments along with the operational constraints of the mission result in tight pointing requirements during all phases of the mission. To ensure the instruments are not damaged during spacecraft safing, thermal constraints dictate that the solar pointing orientation must be maintained to better than 6.5 degrees. This requirement is outside the capabilities of a typical analog sun sensor suite, primarily due to the effects of Earth's albedo. To ensure mission success, a new analog sensor, along with the appropriate algorithms, is needed. This paper discusses the design issues involving albedo effects on spacecraft pointing and the development of a simple, low-cost analog sensor and algorithm that will address the needs of the GPM mission. In addition, the algorithms are designed to be easily integrated into the existing attitude determination software by using common interfaces. The sensor design is based on a heritage, commercial off-the-shelf analog sun sensors with a limited field-of-view to reduce the effects of Earth's albedo. High fidelity simulation results are presented that demonstrate the efficacy of the design

Muscular Hypertrophy of the Pylorus in Infancy

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Implementation Science and Fidelity Measurement: A Test of the 3-5-7 Model™

Children and youths engaged with the child welfare system can experience grief and loss as a result of trauma, broken relationships, and inadequate attachments. Interventionists are often challenged to implement effective strategies that help youths to reestablish trusting relationships and to promote overall psychological well-being. A 5-year federal demonstration project funded by the U.S. Department of Health and Human Services, Children’s Bureau, guided by an implementation science model, sought to increase well-being in youths age 12–21 who were involved in the child welfare system. The 3-5-7 Model™, a strengths-based approach that empowers children, youths, and families to engage in grieving and integrating significant relationships, was studied. A fidelity system was created in order to test the model. Important lessons about implementation science guided the work of the demonstration project. Although definitive conclusions could not be reached, several indicators of psychological well-being were found to be associated with high levels of fidelity to the 3-5-7 ModelTM. Suggestions for future research are offered