An extinct north American porcupine with a South American tail.

New World porcupines (Erethizontinae) originated in South America and dispersed into North America as part of the Great American Biotic Interchange (GABI) 3-4 million years ago. Extant prehensile-tailed porcupines (Coendou) today live in tropical forests of Central and South America. In contrast, North American porcupines (Erethizon dorsatum) are thought to be ecologically adapted to higher-latitude temperate forests, with a larger body, shorter tail, and diet that includes bark.

Sabertooth carcass consumption behavior and the dynamics of Pleistocene large carnivoran guilds.

Apex predators play an important role in the top-down regulation of ecological communities. Their hunting and feeding behaviors influence, respectively, prey demography and the availability of resources to other consumers. Among the most iconic-and enigmatic-terrestrial predators of the late Cenozoic are the Machairodontinae, a diverse group of big cats whose hypertrophied upper canines have earned them the moniker "sabertooths.

Global long-term stability of individual dietary specialization in herbivorous mammals.

Dietary variation within species has important ecological and evolutionary implications. While theoreticians have debated the consequences of trait variance (including dietary specialization), empirical studies have yet to examine intraspecific dietary variability across the globe and through time. Here, we use new and published serial sampled δC values of herbivorous mammals from the Miocene to the present (318 individuals summarized, 4134 samples) to examine how dietary strategy (i.

Flexed-knee gait in children with cerebral palsy: a long-term follow-up study.

Aims: The purpose of this study was to evaluate the long-term outcome of adolescents with cerebral palsy who have undergone single-event multilevel surgery for a flexed-knee gait, followed into young adulthood using 3D motion analysis.

Patients And Methods: A total of 59 young adults with spastic cerebral palsy, with a mean age of 26 years (sd 3), were enrolled into the study in which their gait was compared with an evaluation that had taken place a mean of 12 years (sd 2) previously. At their visits during adolescence, the children walked with excessive flexion of the knee at initial contact and surgical or therapeutic interventions were not controlled between visits.

The effect of continuous intrathecal baclofen therapy on ambulatory children with cerebral palsy.

The effect of a continuous intrathecal infusion of baclofen (CITB) was retrospectively studied in 19 ambulatory children with cerebral palsy (aged 12.4±4.9 years at CITB initiation).

Developing a Clinical Protocol for Habitual Physical Activity Monitoring in Youth With Cerebral Palsy.

Purpose: The StepWatch (SW) has been used to monitor physical activity (PA) in youth with cerebral palsy; however, there is no standard collection protocol. The goal was to develop such a protocol.

Methods: Data were examined from patients who wore the SW for 8 to 14 days.

Pre-operative walking activity in youth with cerebral palsy.

Background: No data are available regarding level of walking activity for youth with cerebral palsy (CP) before undergoing orthopeadic surgery. The goals of this study were to quantify pre-operative walking activity, and determine whether pre-operative values are different from previously defined levels of walking activity in youth with CP.

Procedures: This study retrospectively evaluated pre-operative walking activity in youth with spastic CP, GMFCS levels I-IV.

Evaluating the acromion marker cluster as a method for measuring scapular orientation in children with brachial plexus birth palsy.

Several studies have described using an acromion marker cluster for measuring scapular orientation in healthy adults performing planar motions. It is unknown whether the acromion marker cluster method will provide the same level of accuracy in children with brachial plexus birth palsy. This study compared this method to palpation for calculating scapular orientation in children with brachial plexus birth palsy performing clinically relevant movements.

Scapulothoracic and glenohumeral contributions to motion in children with brachial plexus birth palsy.

Background: Brachial plexus birth palsy occurs in 0.4 to 4.6 of every 1000 live births, with residual shoulder dysfunction in approximately one third of cases.

A new machairodont from the Palmetto Fauna (early Pliocene) of Florida, with comments on the origin of the Smilodontini (Mammalia, Carnivora, Felidae).

South-central Florida's latest Hemphillian Palmetto Fauna includes two machairodontine felids, the lion-sized Machairodus coloradensis and a smaller, jaguar-sized species, initially referred to Megantereon hesperus based on a single, relatively incomplete mandible. This made the latter the oldest record of Megantereon, suggesting a New World origin of the genus. Subsequent workers variously accepted or rejected this identification and biogeographic scenario.

H-NS binding and repression of the ctx promoter in Vibrio cholerae.

Expression of the ctx and tcp genes, which encode cholera toxin and the toxin coregulated pilus, the Vibrio cholerae O1 virulence determinants having the largest contribution to cholera disease, is repressed by the nucleoid-associated protein H-NS and activated by the AraC-like transcriptional regulator ToxT. To elucidate the molecular mechanism by which H-NS controls transcription of the ctxAB operon, H-NS repression and binding were characterized by using a promoter truncation series, gel mobility shift assays, and DNase I footprinting. Promoter regions found to be important for H-NS repression correlated with in vitro binding.

Body temperatures of modern and extinct vertebrates from (13)C-(18)O bond abundances in bioapatite.

The stable isotope compositions of biologically precipitated apatite in bone, teeth, and scales are widely used to obtain information on the diet, behavior, and physiology of extinct organisms and to reconstruct past climate. Here we report the application of a new type of geochemical measurement to bioapatite, a "clumped-isotope" paleothermometer, based on the thermodynamically driven preference for (13)C and (18)O to bond with each other within carbonate ions in the bioapatite crystal lattice. This effect is dependent on temperature but, unlike conventional stable isotope paleothermometers, is independent from the isotopic composition of water from which the mineral formed.

Laboratory Maintenance of Bordetella pertussis.

The causative agent of the respiratory disease whooping cough, Bordetella pertussis, is a nutritionally fastidious microorganism but can be grown with relative ease in research laboratories. Stainer-Scholte synthetic broth medium and Bordet-Gengou blood agar both support growth of B. pertussis and are commonly used.

The subaxial cervical spine injury classification system: a novel approach to recognize the importance of morphology, neurology, and integrity of the disco-ligamentous complex.

Study Design: The classification system was derived through a literature review and expert opinion of experienced spine surgeons. In addition, a multicenter reliability and validity study of the system was conducted on a collection of trauma cases.

Objectives: To define a novel classification system for subaxial cervical spine trauma that conveys information about injury pattern, severity, treatment considerations, and prognosis.

Assessment of injury to the thoracolumbar posterior ligamentous complex in the setting of normal-appearing plain radiography.

Background Context: The posterior ligamentous complex (PLC) is thought to contribute significantly to the stability of thoracolumbar spine. Obvious translation or dislocation of an interspace clearly denotes injury to the PLC. A recent survey of the Spine Trauma Study Group indicated that plain radiographic findings, if present, are most helpful in determining PLC injury.

Assessment of injury to the posterior ligamentous complex in thoracolumbar spine trauma.

Background Context: Posterior ligamentous complex (PLC), consisting of supraspinous ligament (SSL), interspinous ligament (ISL), ligamentum flavum (LF), and the facet joint capsules is thought to contribute significantly to the stability of thoracolumbar spine. Currently, no consensus exists on radiographic imaging parameters that may indicate injury to the posterior ligamentous complex.

Purpose: To identify imaging parameters that may suggest a disruption of the PLC of the thoracolumbar spine.

Thoracolumbar injury classification and severity score: a new paradigm for the treatment of thoracolumbar spine trauma.

Background: Contemporary understanding of the biomechanics, natural history, and methods of treating thoracolumbar spine injuries continues to evolve. Current classification schemes of these injuries, however, can be either too simplified or overly complex for clinical use.

Methods: The Spine Trauma Group was given a survey to identify similarities in treatment algorithms for common thoracolumbar injuries, as well as to identify characteristics of injury that played a key role in the decision-making process.

The thoracolumbar injury severity score: a proposed treatment algorithm.

Objective: Significant controversy exists regarding the optimal management of thoracolumbar injuries. This is in part due to the lack of understanding of the natural history of various injury subtypes and the absence of a universally accepted classification scheme that facilitates communication among care providers and assists in directing treatment. The Spine Trauma Study Group has developed an injury severity score based on three major variables: the mechanism of injury determined by radiographic appearance, the integrity of the posterior ligamentous complex, and the neurologic status of the patient.

Mechanism of ToxT-dependent transcriptional activation at the Vibrio cholerae tcpA promoter.

The AraC homolog ToxT coordinately regulates virulence gene expression in Vibrio cholerae. ToxT is required for transcriptional activation of the genes encoding cholera toxin and the toxin coregulated pilus, among others. In this work we focused on the interaction of ToxT with the tcpA promoter and investigated the mechanism of ToxT-dependent transcriptional activation at tcpA.

Regulated expression of the Streptococcus mutans dlt genes correlates with intracellular polysaccharide accumulation.

Intracellular polysaccharides (IPS) are glycogen-like storage polymers which contribute significantly to Streptococcus mutans-induced cariogenesis. We previously identified and cloned a locus from the S. mutans chromosome which is required for the accumulation of IPS.

The Iowa therapeutic community model of chemical dependency treatment.

A model of inpatient chemical dependency treatment used in several facilities in Iowa is described. Through combining 12 Step, Therapeutic Community and Reality Therapy concepts, the issues of denial, control, and self centeredness are addressed in developmental phases. Individualizing the program through multidisciplinary input is explained in terms of identifying hindrances in perceiving reality and assisting the patients reduce resistance in a downhill process of increasing wholeness and growth.

Time perspective, time attitude, and time orientation in alcoholism: a review.

It has been proposed that alcoholics may have a disrupted subjective sense of time. A review of empirical investigations of alcoholics' psychological time functioning is presented, attempting to carefully distinguish between the concepts of time perspective, time attitude, and time orientation. It is recognized that the label "alcoholic" is not a homogeneous diagnosis, and it is used here for individuals in treatment for problems related to alcohol abuse.

Time and self-identity in later life.

Addressing questions raised by Kastenbaum concerning varied everyday experiences of psychological time, an attempt is made to provide a framework through which such experiences can be interpreted. Raynor's concept of time-linked sources of self-identity is elaborated to include intergenerational-linked and timeless sources of self-identity in the quest to feel good about oneself. Case examples of how eight elderly individuals viewed their futures are used in illustrating how a meaningful sense of self-identity is part of an integration of experiences over time.