Description of an Unusual Cervical Vertebral Column of a Plesiosaur from the Kiowa Shale

The Early Cretaceous (Albian) Kiowa Shale of Clark County, Kansas consists mainly of dark gray shale with occasional limestone deposits that represent a near shore environment. Faunal lists have been published based on fragmentary materials; however, few individual specimens have been described in the last 100 years. Here an unusual plesiosaur specimen (KUVP 16375) is described. The specimen consists of 17 cervical vertebrae: 10 articulated and 7 disarticulated. Some of the vertebrae are uniquely preserved with an atypical ventral excavation not present in known plesiosaur vertebrae. It is not clear whether or not this character is of phylogenetic or diagnostic significance. Many vertebrae lack distinct rib facets. Neural spines are absent from all elements of the specimen. A number of elements possess well-defined zygapophyses and neural canals. Foramina subcentralia are present in the ventral surface of plesiosaur cervical vertebrae but appear to be absent in many of the vertebrae of KUVP 16375. The specimen is described and interpreted as a polycotylid. The specimen is then compared to other plesiosaurs including other polycotylids and its phylogenetic position is analyzed. Character matrices and the physical description allowed referral of the specimen to the Polycotylidae. This family consists of short-necked, large-headed plesiosaurs and is represented by small sample sizes from the Kiowa Shale. Determination of the genus and species is not made at this time

Morphological and biomechanical predictions of cranial kinesis in reptile evolution

Includes vitaFeeding is a complex behavior that all tetrapods engage in on a regular basis to procure energy and survive. The reptilian feeding apparatus includes many types of feeding behaviors including multiple methods of engaging cranial kinesis, the ability to move one portion of the skull in relation to another portion of the skull. Understanding the underlying mechanisms of cranial kinesis enabled feeding mechanism is integral to understanding avian feeding behaviors, strategies, and ecology. Chapter 1 introduces how the feeding apparatus of reptiles is modified during the evolution of birds from dinosaur and reptile relatives. During this introductory chapter I lay the foundation for our knowledge of avian feeding and its evolution and describe the musculoskeletal environment of the avian feeding apparatus, which becomes the main focus of the rest of this project. Chapter 2 explores the diversity of jaw muscle resultants across a sample of birds, dinosaurs and other reptiles using ternary plots. Jaw musculature orientations are altered across ontogeny, behavior, and evolution. I use ternary plots to investigate the diversity of jaw muscle orientations across the ontogeny and feeding behaviors of alligators and through evolution in the dinosaur to bird lineage. Additionally, I use ternary plots to show how diverse organisms use different muscles to produce high bite forces. Chapter 3 introduces and demonstrates the use of postural modeling to investigate the feeding apparatus at a specific instant of a feeding behavior. I investigate the kinetic capability of 3 taxa using this method. I use my postural modeling method to validate postural models of known behaviors in extant taxa first. I then evaluate the kinetic capabilities of an extinct animal, Tyrannosaurus rex. Finally, Chapter 4 investigates the diversity of the feeding apparatus across parrots, a lineage of morphologically comparable birds with distinctive ecological roles. The biomechanical requirements of similar functional morphology used for diverse feeding behaviors are analyzed here. I use statistical and finite element analyses to describe the biomechanical environment of the feeding apparatus in parrots. I analyze stress and strain dissipation as well as geometric properties of bone mechanics that enable parrots to engage in cranial kinesis. I use a phylogenetic tree informed by molecular phylogenies to plot and compare ancestral reconstructions of characters of the feeding apparatus in parrots. My findings using these methods describe the diversity of the musculoskeletal systems of diverse parrots. The data gathered from the studies described here form the foundation of a better understanding of the biomechanics of the avian feeding apparatus. The findings described here will be used in future studies to describe the underlying mechanisms that govern diverse feeding behaviors.Includes bibliographical reference

Emerging novel agents for patients with advanced Ewing sarcoma: a report from the Children’s Oncology Group (COG) New Agents for Ewing Sarcoma Task Force [version 1; peer review: 3 approved]

Ewing sarcoma is a small round blue cell malignancy arising from bone or soft tissue and most commonly affects adolescents and young adults. Metastatic and relapsed Ewing sarcoma have poor outcomes and recurrences remain common. Owing to the poor outcomes associated with advanced disease and the need for a clear research strategy, the Children’s Oncology Group Bone Tumor Committee formed the New Agents for Ewing Sarcoma Task Force to bring together experts in the field to evaluate and prioritize new agents for incorporation into clinical trials. This group’s mission was to evaluate scientific and clinical challenges in moving new agents forward and to recommend agents and trial designs to the Bone Tumor Committee. The task force generated a framework for vetting prospective agents that included critical evaluation of each drug by using both clinical and non-clinical parameters. Representative appraisal of agents of highest priority, including eribulin, dinutuximab, cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitors, anti-angiogenic tyrosine kinase inhibitors, and poly-ADP-ribose polymerase (PARP) inhibitors, is described. The task force continues to analyze new compounds by using the paradigm established

Diffusible iodine-based contrast-enhanced computed tomography (diceCT) : an emerging tool for rapid, high-resolution, 3-D imaging of metazoan soft tissues.

Morphologists have historically had to rely on destructive procedures to visualize the three-dimensional (3-D) anatomy of animals. More recently, however, non-destructive techniques have come to the forefront. These include X-ray computed tomography (CT), which has been used most commonly to examine the mineralized, hard-tissue anatomy of living and fossil metazoans. One relatively new and potentially transformative aspect of current CT-based research is the use of chemical agents to render visible, and differentiate between, soft-tissue structures in X-ray images. Specifically, iodine has emerged as one of the most widely used of these contrast agents among animal morphologists due to its ease of handling, cost effectiveness, and differential affinities for major types of soft tissues. The rapid adoption of iodine-based contrast agents has resulted in a proliferation of distinct specimen preparations and scanning parameter choices, as well as an increasing variety of imaging hardware and software preferences. Here we provide a critical review of the recent contributions to iodine-based, contrast-enhanced CT research to enable researchers just beginning to employ contrast enhancement to make sense of this complex new landscape of methodologies. We provide a detailed summary of recent case studies, assess factors that govern success at each step of the specimen storage, preparation, and imaging processes, and make recommendations for standardizing both techniques and reporting practices. Finally, we discuss potential cutting-edge applications of diffusible iodine-based contrast-enhanced computed tomography (diceCT) and the issues that must still be overcome to facilitate the broader adoption of diceCT going forward

Connecting the chondrocranium: Biomechanics of the suspensorium in reptiles

Gnathostomes all share the common challenge of assembling 1 st pharyngeal arch elements and associated dermal bones (suspensorium) with the neurocranium into a functioning linkage system. In many tetrapods, the otic and palatobasal articulations between suspensorium and neurocranial elements form the joints integral for cranial kinesis. Among sauropsids, the otic (quadratosquamosal) joint is a key feature in this linkage system and shows considerable variability in shape, tissue-level construction and mobility among lineages of reptiles. Here we explore the biomechanics of the suspensorium and the otic joint in five disparate species of sauropsids of different kinetic capacity (two squamates, one non-avian theropod dinosaur, and two avian species). Using 3D muscle modeling, comparisons of muscle moments, joint surface areas, cross-sectional geometries, and finite element analysis, we characterize biomechanical differences in the resultants of protractor muscles, loading of otic joints, and bending properties of pterygoid bones. For the first time, we quantify and directly compare biomechanical descriptors of pterygoid morphology and 3D muscle loads among disparate sauropsids. We propose three classes of pterygoids based on shape on biomechanical loading: brace, propulsive, and torsional. The tubular pterygoids of the lizards and birds appear to experience more diverse loading regimes than the mediolaterally narrow element of the non-avian dinosaur. Our new approaches and findings shed new light on our understanding of evolution and diversity of the suspensorium in tetrapods

TKQML: A Scripting Tool for Building Agents

Tcl/Tk is an attractive language for the design of intelligent agents because it allows the quick construction of prototypes and user interfaces; new scripts can easily be bound at runtime to respond to events; and execution state is encapsulated by the interpreter, which helps in agent migration. However, a system of intelligent agents must share a common language for communicating requests and knowledge. We have integrated KQML (Knowledge Query Manipulation Language), one such standard language, into Tcl/Tk. The resulting system, called TKQML, provides several benefits to those building intelligent agent systems. First, TKQML allows easy integration of existing tools which have Tcl/Tk interfaces with an agent system by using Tcl to move information between KQML and the application. Second, TKQML is an excellent language with which to build agents, allowing on-the-fly specification of message handlers and construction of graphical interfaces. This paper describes the implementation of TKQML, and discusses its use in our intelligent agent system for information retrieval

Abstract Agent Development with Jackal

Jackal is a Java-based tool for communicating with the KQML agent communication language. Some features that make it extremely valuable to agent development are its conversation management facilities, exible, blackboard style interface and ease of integration. Jackal has been developed in support of an investigation of the use of agents in enterprisewide integration of planning and execution for manufacturing.

Agent Development Support for Tcl

Tcl/Tk is an attractive language for the design of intelligent agents because it allows the quick construction of prototypes and user interfaces; new scripts can easily be bound at runtime to respond to events; and execution state is encapsulated by the interpreter, which helps in agent migration. However, a system of intelligent agents must share a common language for communicating requests and knowledge. We have integrated KQML (Knowledge Query Manipulation Language), one such standard language, into Tcl/Tk. The resulting system, called TKQML, provides several benefits to those building intelligent agent systems. First, TKQML allows easy integration of existing tools which have Tcl/Tk interfaces with an agent system by using Tcl to move information between KQML and the application. Second, TKQML is an excellent language with which to build agents, allowing on-the-fly specification of message handlers and construction of graphical interfaces. This paper describes the implementation of..

Data from: The roles of joint tissues and jaw muscles in palatal biomechanics of the Savannah monitor (Varanus exanthematicus) and their significance for cranial kinesis

Many vertebrates exhibit cranial kinesis, or movement between bones of the skull other than at the jaw joint. Many kinetic species possess a particular suite of features to accomplish this movement, including flexible cranial joints and protractor musculature. Whereas the skeletal anatomy of these kinetic systems is well understood, how these joints are biomechanically loaded, how different soft tissues affect joint loading and kinetic capacity, and how the protractor musculature loads the skull remain poorly understood. Here we developed a Finite Element Model of the savannah monitor, Varanus exanthematicus, a modestly kinetic lizard, to better elucidate the roles of soft tissue in mobile joints and protractor musculature on cranial loading. We described the 3D resultants of jaw muscles and histology of palatobasal, otic and jaw joints. We tested the effects of joint tissue types, bite point, and muscle loads to evaluate the biomechanical role of muscles have on the palate and braincase. We found the jaw muscles have significant mediolateral components and resultants that can impart stability across palatocranial joints. We found articular tissues affect the magnitude of strains experienced across the palatobasal and otic joints. We found that without protractor muscle loading, the palate, quadrate and braincase experience higher strains suggesting this muscle helps insulate the braincase and palatoquadrate from high loads. Finally, we found the cross-sectional properties of the bones of Varanus exanthematicus is well suited for performing under torsional loads. These findings suggest that torsion may be a significant driver in the evolution of cranial kinesis in lepidosaurs