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In the wake of the Deepwater Horizon disaster, much has been learned about the biological, ecological, physical, and chemical conditions of the Gulf of Mexico. In parallel, the research community has also gained insight about the social and organizational structures and processes necessary for oil spill response and subsequent marine and coastal restoration. However, even with these lessons from both the Deepwater Horizon and previous spills, including 1989's Exxon Valdez and the Ixtoc 1 in 1979, our understanding of how to avoid future crises has not advanced at the same pace as offshore oil and gas development. We argue that this progress deficit indicates a continued devaluing of marine and coastal resources. We believe that we must, instead, advance a proactive conservation ethic based on the precautionary principle and an appropriately placed burden of proof-strategies that will help reduce our reliance on costly restoration and protect marine and coastal ecosystems., (© The Author(s) 2019. Published by Oxford University Press on behalf of the American Institute of Biological Sciences.)

Study Design: Prospective longitudinal study of growth modulation system for early adolescent idiopathic scoliosis (AIS), consecutive case series from first human use to skeletal maturity, fusion, or five years postoperation., Objectives: Determine adverse events and curvature changes to end of study; examine factors most likely to explain variability in curve changes., Summary of Background: Pilot clinical safety study was performed under US Food and Drug Administration (FDA) Investigational Device Exemption (IDE). Safety and radiographic results were previously reported to 24 months postoperation., Methods: Subjects with early AIS underwent thoracoscopic placement of titanium clip-screw devices designed to modify growth asymmetrically. Eligibility was based on high risk of progression to 50°: single major thoracic curve 25°-40°, Risser 0, open triradiate cartilages, and premenarchal if female. Six subjects, the maximum allowed, enrolled. Adverse events (AEs), clinical outcomes, and curvatures were systematically collected. Disc heights, vertebral heights, and implant-bone contact areas were assessed., Results: Consecutive subjects enrolled, aged 12.1 years (±1.7), three were female. AEs from two to five years postoperation included deformity changes leading to a second surgery in three patients: two for posterior spinal fusion, and one for thoracoscopic removal of half the implants for overcorrection. In the latter case, overcorrection appeared halted for duration of study. One patient, whose curve exceeded 50° at age 18 years, did not choose fusion. Major thoracic curves were 34° (±3°) preoperatively and 42° (±20°) at end of study., Conclusions: In a study of spine growth modulation in patients with early AIS with high risk of progression, at skeletal maturity or five years postoperation, major thoracic curves of half progressed to >50°, whereas curves of the other half remained <40°, below fusion indications. Removal of selected implants may halt overcorrection. The next, pivotal, study phase was approved by FDA., Level of Evidence: Level IV, prospective case series under stringent regulatory controls., (Copyright © 2019 Scoliosis Research Society. Published by Elsevier Inc. All rights reserved.)

Background: Bisphenol A (BPA) is commonly used in the manufacture of plastics and epoxy resins. In North America, over 90% of the population has detectable levels of urinary BPA. Human epidemiological studies have reported adverse behavioral outcomes with BPA exposure in children, however, corresponding effects on children's brain structure have not yet been investigated. The current study examined the association between prenatal maternal and childhood BPA exposure and white matter microstructure in children aged 2 to 5 years, and investigated whether brain structure mediated the association between BPA exposure and child behavior., Methods: Participants were 98 mother-child pairs who were recruited between January 2009 and December 2012. Total BPA concentrations in spot urine samples obtained from mothers in the second trimester of pregnancy and from children at 3-4 years of age were analyzed. Children participated in a diffusion magnetic resonance imaging (MRI) scan at age 2-5 years (3.7 ± 0.8 years). Associations between prenatal maternal and childhood BPA and children's fractional anisotropy and mean diffusivity of 10 isolated white matter tracts were investigated, controlling for urinary creatinine, child sex, and age at the time of MRI. Post-hoc analyses examined if alterations in white matter mediated the relationship of BPA and children's scores on the Child Behavior Checklist (CBCL)., Results: Prenatal maternal urinary BPA was significantly associated with child mean diffusivity in the splenium and right inferior longitudinal fasciculus. Splenium diffusivity mediated the relationship between maternal prenatal BPA levels and children's internalizing behavior (indirect effect: β = 0.213, CI [0.0167, 0.564]). No significant associations were found between childhood BPA and white matter microstructure., Conclusions: This study provides preliminary evidence for the neural correlates of BPA exposure in humans. Our findings suggest that prenatal maternal exposure to BPA may lead to alterations in white matter microstructure in preschool aged children, and that such alterations mediate the relationship between early life exposure to BPA and internalizing problems.

Structural and functional neuroimaging studies show language and reading processes are left-lateralized, and associated with a dispersed group of left brain regions. However, it is unclear when and how asymmetry of these regions emerges. We characterized the development of structural and functional asymmetry of the language network in 386 datasets from 117 healthy children (58 male) across early childhood (2-7.5 years). Structural asymmetry was investigated using diffusion tensor imaging (DTI) and manual delineation of the arcuate fasciculus. Functional connectivity asymmetry was calculated from seed regions in the inferior frontal gyrus (IFG) and middle temporal gyrus (MTG). We show that macrostructural asymmetry of the arcuate fasciculus is present by age 2 years, while leftward asymmetry of microstructure and functional connectivity with the IFG increases across the age range. This emerging microstructural and functional asymmetry likely underlie the development of language and reading skills during this time., (Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.)

White matter development continues throughout childhood and into early adulthood, but few studies have examined early childhood, and the specific trajectories and regional variation in this age range remain unclear. The aim of this study was to characterize developmental trajectories and sex differences of white matter in typically developing young children. Three hundred and ninety-six diffusion tensor imaging datasets from 120 children (57 male) aged 2-8 years were analyzed using tractography. Fractional anisotropy (FA) increased and mean diffusivity (MD) decreased in all white matter tracts by 5-15% over the 6-year period, likely reflecting increases in myelination and axonal packing. Males showed steeper slopes in a number of brain areas. Overall, early childhood is associated with substantial development of all white matter and appears to be an important period for the development of occipital and limbic connections, which showed the largest changes. This study provides a detailed characterization of age-related white matter changes in early childhood, offering baseline data that can be used to understand cognitive and behavioural development, as well as to identify deviations from normal development in children with various diseases, disorders, or brain injuries., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background: It has been hypothesised that abnormal functioning of the mirror neuron system (MNS) may lead to deficits in imitation and the internal representation of movement, potentially contributing to the motor impairments associated with developmental coordination disorder (DCD)., Aims: Using fMRI, this study examined brain activation patterns in children with and without DCD on a finger adduction/abduction task during four MNS activation states: observation; motor imagery; execution; and imitation., Methods and Procedures: Nineteen boys (8.25-12.75 years) participated, including 10 children with DCD (≤16th percentile on MABC-2; no ADHD/ASD), and nine typically developing controls (≥25th percentile on MABC-2)., Outcomes and Results: Even though children with DCD displayed deficits behaviourally on imitation (Sensory Integration & Praxis Test Subtests) and motor imagery assessments prior to scanning, no differences in MNS activation were seen between the DCD and control groups at a neurological level, with both groups activating mirror regions effectively across conditions. Small clusters of decreased activation during imitation were identified in non-mirror regions in the DCD group, including the thalamus, caudate, and posterior cingulate - regions involved in motor planning and attentional processes., Conclusions and Implications: The results of this study do not provide support for the MNS dysfunction theory as a possible causal mechanism for DCD. Further research to explore attentional and motor planning processes and how they may interact at a network level may enhance our understanding of this complex disorder., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Background: Developmental coordination disorder (DCD) is a motor learning disability that affects coordination resulting in an inability to perform movement skills at an age appropriate level. One area suspected to contribute to the movement difficulties experienced are deficits in visuomotor control., Aims: This study investigated visual tracking behaviour during catching in children with DCD., Methods and Procedures: Twenty-four boys completed the study: 11 with DCD (9.43 years ±0.73) and 13 controls (9.16 years ± 0.68). Participants performed 10 central catching trials, with the best five used to evaluate tracking behaviour and motor responses., Outcomes and Results: Prior to ball release, the DCD group exhibited more fixations (p = 0.043) of lesser duration (p = 0.045). During flight, the DCD group took longer to initiate smooth pursuit (p = 0.003) however, once initiated, both groups were effectively able to maintain smooth pursuit. Despite initial delays, these had no impact on movement initiation time (p = 0.173), however, movement time was significantly slower in the DCD group (p = 0.031)., Conclusions and Implications: The results of this study demonstrate that catching performance in children with DCD likely reflect a combination of errors in attending to visual information and movement organisation., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The preschool period is a time of significant physical and behavioral growth, including the improvement of gross and fine motor skills. Although motor development has been comprehensively mapped from infancy to adulthood, the neural correlates associated with motor advancements during early childhood remain unclear. The current study used diffusion tensor imaging (DTI) to delineate key motor pathways and characterize their relationships with motor performance in 80 typically developing preschool children, aged 3-6 years. The Movement Assessment Battery for Children-2nd edition (MABC-II) was used to assess motor functioning. Partial correlations between DTI parameters and motor performance, controlling for sex and age, revealed a positive correlation between motor performance and fractional anisotropy of corpus callosum motor fibers, as well as negative correlations of motor performance with mean and radial diffusivity. These results appear to be driven by females, as correlations were significant in girls but not boys when analyzed separately. Mean corticospinal tract (CST) diffusion parameters were not significantly related to motor performance, but relationships were observed at regionally specific locations along the bilateral CST. These findings suggest preschool-aged children with better motor performance show more mature white matter patterns within motor pathways, and that the structural variation in these pathways may partially account for the natural variability in motor performance., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Kinetic CO2 adsorption measurements in the water-stable and permanently microporous Metal-organic framework material, Mg-CUK-1, reveal a 1.8-fold increase in CO2 capture from 4.6 wt% to 8.5 wt% in the presence of 18% relative humidity. Thermodynamic CO2 uptake experiments corroborate this enhancement effect, while grand canonical Monte Carlo simulations also support the phenomenon of a humidity-induced increase in the CO2 sorption capacity in Mg-CUK-1. Molecular simulations were implemented to gain insight into the microscopic adsorption mechanism responsible for the observed CO2 sorption enhancement. These simulations indicate that the cause of increasing CO2 adsorption enthalpy in the presence of H2O is due to favorable intermolecular interactions between the co-adsorbates confined within the micropores of Mg-CUK-1.

The new ligand tris(p-carboxyphenylethynyl)phosphine (P{C[triple bond, length as m-dash]CC 6 H 4 -4-CO 2 H} 3 ) was used to synthesize a permanently porous Mn(ii)-based acetylenic phosphine coordination material, PCM-48. This triply-interpenetrated MOF contains 1-D microchannels that are decorated with electron-rich and adsorbate-accessible acetylenic moieties and phosphine lone pairs. PCM-48 has a moderate room-temperature C 2 H 2 adsorption capacity (25.54 cm 3 g -1 ) and displays high separation selectivities for C 2 H 2 over CH 4 (C 2 H 2 /CH 4 = 23.3), CO 2 (C 2 H 2 /CO 2 = 4.3), and N 2 (C 2 H 2 /N 2 = 76.9) at 296 K.

ACM-1 is the first example of an organoarsine metal-organic framework (MOF), prepared using a new pyridyl-functionalized triarylarsine ligand coordinated to Ni(II) nodes. ACM-1 has micropores that are decorated with cis-diarsine coordination pockets. Postsynthetic metalation of ACM-1 with AuCl under facile conditions studied by single-crystal X-ray diffraction reveals the installation of dimeric Au 2 Cl 2 complexes via the formation of As-Au bonds. The Au(I) dimers display exceptionally short aurophilic bonds (2.76 Å) induced by the rigidity of the MOF, which acts as a unique solid-state ligand.

Light-emitting electrochemical cells (LEECs) from ionic transition-metal complexes (iTMCs) offer the potential for high-efficiency electroluminescence in a simple, single-layer device. However, LEECs typically rely on the use of rare metal complexes. This has limited their cost effectiveness and put constraints on their applicability. With a view to leveraging the efficient emission of these complexes while mitigating costs, we describe here a host/guest LEEC strategy that relies on the use of carbazole (Cz)-based organic small-molecule hosts and iTMC guests. Three cationic host molecules were prepared via the coupling of 1-(4-bromophenyl)-2-phenylbenzimidazole (PBI-Br) with Cz. This has allowed a comparison between the hosts bearing methoxy (PBI-CzOMe) and tert-butyl (PBI-Cz tBu) substituents, as well as an unsubstituted analogue (PBI-CzH). Cyclic voltammetry and UV-visible absorption revealed that all three host materials have wide band gaps characterized by reversible oxidation and irreversible reduction events. On the basis of electronic structure calculations, the host highest occupied molecular orbital (HOMO) resides primarily on the Cz moiety, whereas the lowest unoccupied molecular orbital (LUMO) is located primarily on the phenyl-benzimidazolium unit. Photoluminescence analysis of thin-film blends of PBI-CzH with iTMC guests confirmed that the emission was blue-shifted relative to pristine iTMC films, which is consistent with what was seen in dilute dichloromethane solution. LEEC devices were prepared based on thin films of the pristine hosts, pristine guests, and 90%/10% (w/w) host/guest blends. Among these host/guest blends, LEECs based on PBI-CzH displayed the best performance, particularly when an iridium complex was used as the guest. The system in question yielded a luminance maximum of 624 cd/m 2 at an external quantum efficiency of 3.80%. This result stands in contrast to what is seen with typical organic light-emitting diode host studies, where tert-butyl substitution of the host generally leads to a better performance. To rationalize the present observations, the host materials were subject to single-crystal X-ray diffraction analysis. The resulting structures revealed clear head-to-tail interactions in the case of both PBI-CzH and PBI-CzOMe. No such interactions were evident in the case of PBI-Cz tBu. Furthermore, PBI-CzH showed a relatively smaller spacing between the successive HOMO and successive LUMO levels relative to PBI-CzOMe and PBI-Cz tBu, a finding consistent with more favorable charge transport and energy transfer. The results presented here can help inform the design and preparation of host materials suitable for use in single-layer iTMC LEECs.

PCM-101 is a phosphine coordination material comprised of tris(p-carboxylato)triphenylphosphine and secondary pillaring groups coordinated to [M 3 (OH)] 5+ nodes (M=Co, Ni). PCM-101 has a unique topology in which R 3 P: sites are arranged directly trans to one another, with a P⋅⋅⋅P separation distance dictated by the pillars. Post-synthetic coordination of soft metals to the P: sites proceeds at room temperature to provide X-ray quality crystals that permit full structural resolution. Addition of AuCl groups forces a large distortion of the parent framework. In contrast, CuBr undergoes insertion directly between the trans-P sites to form dimers that mimic solution-phase complexes, but that are geometrically strained due to steric pressure exerted by the MOF scaffold. The metalated materials are active in heterogeneous hydroaddition catalysis under mild conditions, yielding different major products compared to their molecular counterparts., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Florida manatees (Trichechus manatus latirostris) possess an unusual suite of adaptations to accommodate both a fully aquatic lifestyle and an herbivorous diet, including a low metabolic rate and a very limited thermoneutral zone. Their relatively high lower critical temperature of around 20 °C suggests strong sensitivity to cold, thereby limiting their distribution to tropical and subtropical waters. "Cold stress syndrome" affects and kills Florida manatees every year during intense or prolonged cold weather, posing one of the major threats to manatees. However, knowledge regarding manatee thermoregulation is sparse, but essential for effective conservation and management of this threatened species. We measured heat flux in two captive Florida manatees at multiple times of the year, at 41 sites distributed across the entire body surface of each manatee. Heat flux differed significantly between individuals, and among body sites and times of the year. The pectoral flippers and axillae were identified as areas with highest heat exchange. Despite exposure to constant water temperature throughout the year, the manatees in this study had significantly lower heat flux in winter than in summer. We used the measured heat flux values to calculate total heat dissipation in individual manatees. The values estimated this way correspond well with the low metabolic rates estimated in previous studies, confirming the reliability of our novel approach. Our method provides simple and useful options for enhancing manatee welfare by monitoring the animals' thermal state during potentially stressful activities such as during medical treatment, capture restraints and transportation.

Study Design: Prospective pilot clinical safety study of novel treatment, consecutive case series from first human use in patients with early adolescent idiopathic scoliosis (AIS)., Objective: The primary purpose was to determine the initial safety of a titanium clip-screw implant system for spine growth modulation. The secondary aim was to document curvatures to 2 years postoperatively., Summary of Background Data: Spinal growth modulation was documented in preclinical studies. A prospective pilot clinical safety study was then performed under a Food and Drug Administration (FDA) Investigational Device Exemption (IDE) (www.clinicaltrials.gov Identifier: NCT01465295)., Methods: Six subjects with early AIS underwent thoracoscopic placement of titanium clip-screw devices. Eligibility criteria included only patients at high risk for progression to 50°: single major thoracic curve 25°-40°, age ≥10 years, skeletally immature (Risser 0 plus open triradiate cartilages), and if female, premenarchal. Adverse events (AEs), clinical outcomes, and radiographic measures were documented using Good Clinical Practices., Results: Six consecutive subjects were enrolled, three females and three males aged 12.1 years (±1.7). AEs included one that was device related-mild device migration at 18 months in the most rapidly progressive curve. Procedure-related AEs were mostly pulmonary. A chylous effusion that met the clinical protocol definition of a serious AE resolved after minimally invasive interventions. Major thoracic curves were 34° (±3°) preoperatively and 38° (±18°) at two years (intrasubject change, 4° ± 18°). At 24 months, curves in 3 patients were >45° and 3 were <40°., Conclusions: A spine growth modulation system undergoing study under an FDA IDE was determined to be safe. Variability in curve response to the implant was high, ranging from progression to correction. Investigational approval was granted by the US FDA for the next cohort of 30 subjects., (Copyright © 2017 Scoliosis Research Society. Published by Elsevier Inc. All rights reserved.)

It has been hypothesized that deficits in imitation, linked to abnormal functioning of the mirror neuron system (MNS), may contribute to the motor impairments associated with developmental coordination disorder (DCD). The authors aimed to examine imitation of complex novel postures and sequences of gestures in children with and without probable DCD (pDCD), using the postural praxis and sequencing praxis subtests of the Sensory Integration and Praxis Tests (Ayres, 1989 ). Participants were 29 boys with pDCD between 6.08 and 13.33 years old, and 29 group age-matched typically developing boys between 6.08 and 13.83 years old. Responses of children with pDCD on both imitation tasks were less accurate than controls, with group differences more apparent with increasing task complexity. Furthermore, as a group, children with pDCD were slower and had a higher number of non-mirror-imitated responses. There was considerable variability within the pDCD group, with some children displaying imitation scores within the normative range. Given the importance of imitation and visual learning for motor development, the difficulties in imitation displayed by some children with pDCD have the potential to impact on movement acquisition. Interventions to target imitation may be beneficial for these children. The results show that children with pDCD had difficulty imitating complex novel postures, children with pDCD had difficulty imitating gesture sequences, children with pDCD had slower responses than controls, group differences in imitation performance increased with task complexity, and not all children with pDCD displayed imitation deficits.

Background and Objectives: Developmental coordination disorder (DCD) is a prevalent childhood movement disorder, impacting the ability to perform movement skills at an age appropriate level. Although differences in grey matter (GM) volumes have been found in related developmental disorders, no such evidence has been linked with DCD to date. This cross-sectional study assessed structural brain differences in children with and without DCD., Methods: High-resolution structural images were acquired from 44 children aged 7.8-12 years, including 22 children with DCD (≤16th percentile on MABC-2; no ADHD/ASD), and 22 typically developing controls (≥20th percentile on MABC-2). Structural voxel-based morphology analysis was performed to determine group differences in focal GM volumes., Results: Children with DCD were found to have significant, large, right lateralised reductions in grey matter volume in the medial and middle frontal, and superior frontal gyri compared to controls. The addition of motor proficiency as a covariate explained the between-group GM volume differences, suggesting that GM volumes in motor regions are reflective of the level of motor proficiency. A positive correlation between motor proficiency and relative GM volume was also identified in the left posterior cingulate and precuneus., Conclusions: GM volume reductions in premotor frontal regions may underlie the motor difficulties characteristic of DCD. It is possible that intervention approaches targeting motor planning, attention, and executive functioning processes associated with the regions of reduced GM volume may result in functional improvements in children with DCD., (Copyright © 2017 ISDN. Published by Elsevier Ltd. All rights reserved.)

Background and Objectives: To conduct a systematic review of the evidence for the management of tone in infants 0-24 months of age, with or at risk of developing cerebral palsy., Method: This review was conducted and reported following the Preferred Reporting Items for Systematic Reviews and Meta-analyses Statement. The Cochrane Central Register of Controlled Trials, Embase, MEDLINE, CINAHL Plus and PsycINFO databases were systematically searched for relevant articles. Inclusion criteria were: children aged 0-24 months, identified as at risk of, or having cerebral palsy; ≥25% of participants ≤24 months, and included a standardized assessment of tone. Only peer reviewed journal articles were considered. Eligible studies were coded using the Oxford Levels of Evidence. Methodological quality was assessed using the PEDro scale for randomized controlled trials and the checklist for assessing the quality of quantitative studies of Kmet, Cook and Lee for non-randomized control trials., Results: A total of 4838 studies were identified. After removing duplicates and unrelated studies, a total of 56 full text studies were reviewed. A total of five studies met inclusion criteria, two of which were RCTs, two pre-/post-test designs and one retrospective case audit. Interventions included BoNT-A, Oral Baclofen, Neurofacilitation of Developmental Reaction and Neurodevelopmental Therapy. The quality of evidence ranged from limited to moderate., Conclusion: The management of tone in infants and young children is not well described, with a dearth of high-level evidence to support intervention in the 0-24 month age-range. This is in contrast to a recent review completed by Novak et al. (2013) who report high levels of evidence of interventions for children with cerebral palsy, over 2 years of age. Implications for Rehabilitation High level of evidence to support clinical decision making for the management of tone in young children 0-24 months is not available. The lack of available evidence in the management of tone of young children underpins service delivery and intervention and impacts on patient outcomes. In the absence of clear research evidence, the systematic application of sensitive outcome measures is required to confirm treatment effects and generate new evidence. Hypertonia should not be managed in isolation. Consideration needs to be given to all components of the ICF-CY.

Despite the considerable resources allocated to research to promote public health, interventions capable of benefiting individuals and families are not finding their way into regular practice. An important avenue for addressing this problem is through dissemination and implementation (D&I) science, a burgeoning research area focusing on translating empirical knowledge into everyday practice. This article begins by suggesting ways in which MFTs are uniquely equipped to contribute to and benefit from D&I research. We will then provide an overview of D&I research, outlines key D&I models, and highlight examples of family intervention research relevant to MFTs using the key models. Finally, we conclude by providing the field with important next steps to advance the presence of MFT research within D&I scholarship., (© 2016 American Association for Marriage and Family Therapy.)

Study Objective: Volatile anesthetic agents comprise a substantial portion of every hospital's pharmacy budget. Challenged with an initiative to lower anesthetic drug expenditures, we developed an education-based intervention focused on reducing volatile anesthetic costs while preserving access to all available volatile anesthetics. When postintervention evaluation demonstrated a dramatic year-over-year reduction in volatile agent acquisition costs, we undertook a retrospective analysis of volatile anesthetic purchasing data using time series analysis to determine the impact of our educational initiative., Design/setting: We obtained detailed volatile anesthetic purchasing data from the Central Supply of Wake Forest Baptist Health from 2007 to 2014 and integrated these data with the time course of our educational intervention., Patients: Aggregate volatile anesthetic purchasing data were analyzed for 7 consecutive fiscal years., Intervention: The educational initiative emphasized tissue partition coefficients of volatile anesthetics in adipose tissue and muscle and their impact on case management., Measurements: We used an interrupted time series analysis of monthly cost per unit data using autoregressive integrated moving average modeling, with the monthly cost per unit being the amount spent per bottle of anesthetic agent per month., Main Results: The cost per unit decreased significantly after the intervention (t=-6.73, P<.001). The autoregressive integrated moving average model predicted that the average cost per unit decreased $48 after the intervention, with 95% confidence interval of $34 to $62. As evident from the data, the purchasing of desflurane and sevoflurane decreased, whereas that of isoflurane increased., Conclusions: An educational initiative focused solely on the selection of volatile anesthetic agent per case significantly reduced volatile anesthetic expense at a tertiary medical center. This approach appears promising for application in other hospitals in the rapidly evolving, value-added health care environment. We were able to accomplish this with instruction on tissue partition coefficients and each agent's individual cost per MAC-hour delivered., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Objectives: Parents experiencing racial discrimination are likely to transmit racial socialization messages to their children to protect them from future injustices. This study was conducted to better understand the role of parents' racial discrimination in their racial socialization practices for 2-parent African American families., Method: Using a sample from the Promoting Strong African American Families (N = 322 couples) program, we examined the effects of experienced discrimination on one's own and one's partner's racial socialization practices with male (n = 154) and female (n = 168) offspring., Results: Multiple-group actor-partner interdependence models showed that racial discrimination was associated with racial socialization practices. In addition, maternal experiences of discrimination had stronger relations to socialization messages relayed to daughters and greater paternal experiences of discrimination had stronger relations to socialization messages given to sons., Conclusions: This study demonstrates variability in how male and female children in African American families are socialized as a result of their parents' experiences with racial discrimination., ((c) 2016 APA, all rights reserved).)

It has been hypothesised that deficits in the functioning of the mirror neuron system (MNS) and internal modelling may contribute to the motor impairments associated with DCD. These processes can be explored behaviourally through motor imagery paradigms. Motor imagery proficiency of children with and without probable DCD (pDCD) was examined using a complex hand rotation task to explore whether motor imagery strategies could be used during more complex tasks. Forty-four boys aged 7-13 years participated, 22 with pDCD (mean = 9.90 years ± 1.57) and 22 controls (mean = 9.68 years ± 1.53). Participants completed the task twice: with and without motor imagery instructions. Stimuli were presented in two rotational axes--palm/back, and eight 45° rotational steps. Both groups showed evidence of following the biomechanical and postural constraints of actual movements. Responses of children with pDCD were slower and less accurate than controls, with group differences increasing alongside task complexity. A greater impact of biomechanical constraints for accuracy was observed in the DCD group. The response characteristics of children with pDCD likely reflects a reduced capacity to mentally manipulate a body schema and reduced visuo-motor processing capabilities. Behaviourally, these processes are linked to MNS and internal modelling function, suggesting deficits in these systems may contribute to the movement difficulties characteristic of DCD., (Copyright © 2015 Elsevier B.V. All rights reserved.)

The aim of this study was to reveal cortical areas that may contribute to the movement difficulties seen in children with Developmental Coordination Disorder (DCD). Specifically, we hypothesized that there may be a deficit in the mirror neuron system (MNS), a neural system that responds to both performed and observed actions. Using functional MRI, 14 boys with DCD (x=10.08 years ± 1.31, range=7.83-11.58 years) and 12 typically developing controls (x=10.10 years ± 1.15, range=8.33-12.00 years) were scanned observing, executing and imitating a finger sequencing task using their right hand. Cortical activations of mirror neuron regions, including posterior inferior frontal gyrus (IFG), ventral premotor cortex, anterior inferior parietal lobule and superior temporal sulcus were examined. Children with DCD had decreased cortical activation mirror neuron related regions, including the precentral gyrus and IFG, as well as in the posterior cingulate and precuneus complex when observing the sequencing task. Region of interest analysis revealed lower activation in the pars opercularis, a primary MNS region, during imitation in the DCD group compared to controls. These findings provide some preliminary evidence to support a possible MNS dysfunction in children with DCD., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Purpose: The aim of this systematic review was to investigate the evidence of abnormal functioning of the mirror neuron system (MNS) in children and adults with developmental coordination disorder (DCD), through examination of imitation, motor imagery, and neuroimaging literature., Methods: The following databases were comprehensively searched for relevant articles: CINAHL Plus, Embase, MEDLINE, PsycINFO, Pubmed, and Web of Science. Full-text articles of all potentially relevant citations were obtained and assessed for eligibility by two authors. Outcome measures of interest at a motor behaviour level were any measures of imitation or motor imagery proficiency and, at a neurological level, were any measures of neural activity in MNS brain regions. Due to differences in outcome measures between studies and the variables reported, a narrative review was undertaken to synthesise findings from the studies., Results: Overall, 31 articles met the inclusion criteria. Children and adults with DCD display deficits imitating meaningful and novel gestures and demonstrate different response patterns to controls when undertaking complex motor imagery tasks. Children with DCD present reduced activation and connectivity of frontal, parietal, and temporal MNS regions., Conclusions: Preliminary evidence indicates some deficit in the functioning of the MNS at a motor behaviour and neurological level. As no published neuroimaging studies have been designed specifically to explore MNS function, these results must be interpreted with caution. Further research to explore the MNS hypothesis in greater detail, particularly from a neuroimaging perspective, has the potential to provide information on the underlying mechanisms of DCD, inform future research into the aetiology of this disorder, and inform intervention approaches., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

HFPO-Amidol (CAS # 75888-49-2) is a new hexafluoropropylene oxide (HFPO)-based intermediate developed as an alternative to longer chain perfluorinated compounds. The repeated-dose toxicity of this material was evaluated in an Organization for Economic Cooperation and Development 422-compliant, 28-day oral exposure study with a concurrent reproductive/developmental toxicity screening test. Wistar rats received doses of 0, 30, 300, or 1000 mg/kg/d by oral gavage. Statistically significant changes in body weight gain of 1000 mg/kg/d females during the postcoitum period were possibly related to treatment but were considered not adverse, given the slight nature of the changes. The lower food consumption of 300 mg/kg/d females during the postcoitum and lactation period was not considered treatment related given the absence of a time- and dose-related trend and because food intake was generally similar to control levels after allowance for body weights. Statistically significant changes in motor activity (total movements and total ambulations) were noted in 1000 mg/kg/d main male and female rats. The changes observed in female rats were considered not treatment related in the absence of a dose-response trend. The higher motor activity of high-dose males was primarily apparent within the first 10 minutes of the 60-minute measurement period and was suggestive of temporary hyperreactivity to a new environment/stimulus. This increased peak motor activity remained present although at an apparent lower magnitude when measured 13 days after withdrawal of treatment. Because the possible toxicological relevance of the temporarily increased motor activity observed in 1000 mg/kg/d males could not be excluded, these changes were considered possibly adverse in nature. No treatment-related or toxicologically relevant effects were noted on the other parental, reproductive, and developmental parameters investigated in this study. The parental systemic no observed adverse effect level (NOAEL) for this study is 300 mg/kg/d (based on increased motor activity in males), while the reproductive and developmental NOAEL is 1000 mg/kg/d., (© The Author(s) 2015.)

There is growing interest in the use of consumer level exergames in movement skill acquisition. The purpose of this study was to investigate the relationship between movement proficiency and performance in virtual exergaming. Twenty seven children, aged 10-15years participated in an experiment completing the Movement Assessment Battery for Children 2 (MABC-2) and a series of XBOX360 Kinect Sports exergaming tasks. Significant correlations were observed between MABC-2 aiming and catching percentile and exergame javelin and target kick, where the more proficient movers tended to perform better in the exergame. Statistically significant correlations were observed between MABC-2 balance percentile and exergaming sprint and target kick performance. In this study children who scored better in real life gross motor movement tasks performed better in most related exergaming activities. This suggests current exergaming technology has advanced to a point where body movement unencumbered by a physical or remote game device tether can extract movements resembling real life tasks, translate them into game play and reward proficient movers with higher in-game performance. It is possible that benefit gained in an exergaming environment by more proficient movers was a result of either their more proficient movement, or a greater ability to adapt to the exergame., (Copyright © 2014 Elsevier B.V. All rights reserved.)

The effect of pH on the spectral and redox properties of model GFP synthetic chromophores (Cros) in a universal buffer system was investigated. The Cro hydroxy-derivatives demonstrated a Nernst-type electrochemical dependence of the anodic potential within the pH 2-8 range. Analogous studies on various fluorescent proteins were unsuccessful.

We used southwestern Florida as a case study to lay the groundwork for an intended and organized decision-making process for managing warm-water habitat needed by endangered manatees to survive winters in Florida. Scientists and managers have prioritized (a) projecting how the network of warm-water sites will change over the next 50 years as warmed industrial discharges may expire and as flows of natural springs are reduced through redirection of water for human uses, and (b) mitigating such changes to prevent undue consequences to manatees. Given the complexities introduced by manatee ecology; agency organizational structure; shifting public demands; fluctuating resource availability; and managing within interacting cultural, social, political, and environmental contexts, it was clear that a structured decision process was needed. To help promote such a process, we collected information relevant to future decisions including maps of known and suspected warm-water sites and prototyped a characterization of sites and networks. We propose steps that would lead to models that might serve as core tools in manatee/warm-water decision-making, and we summarized topics relevant for informed decision-making (e.g., manatee spatial cognition, risk of cold-stress morbidity and mortality, and human dimensions). A major impetus behind this effort is to ensure proactively that robust modeling tools are available well in advance of the anticipated need for a critical management decision.

To survive cold winter periods most, if not all, Florida manatees rely on warm-water refuges in the southern two-thirds of the Florida peninsula. Most refuges are either warm-water discharges from power plant and natural springs, or passive thermal basins that temporarily trap relatively warm water for a week or more. Strong fidelity to one or more refuges has created four relatively discrete Florida manatee subpopulations. Using statewide winter counts of manatees from 1999 to 2011, we provide the first attempt to quantify the proportion of animals using the three principal refuge types (power plants, springs, and passive thermal basins) statewide and for each subpopulation. Statewide across all years, 48.5% of all manatees were counted at power plant outfalls, 17.5% at natural springs, and 34.9 % at passive thermal basins or sites with no known warm-water features. Atlantic Coast and Southwest Florida subpopulations comprised 82.2% of all manatees counted (45.6% and 36.6%, respectively) with each subpopulation relying principally on power plants (66.6% and 47.4%, respectively). The upper St. Johns River and Northwest Florida subpopulations comprised 17.8% of all manatees counted with almost all animals relying entirely on springs (99.2% and 88.6% of those subpopulations, respectively). A record high count of 5,076 manatees in January 2010 revealed minimum sizes for the four subpopulations of: 230 manatees in the upper St. Johns River; 2,548 on the Atlantic Coast; 645 in Northwest Florida; and 1,774 in Southwest Florida. Based on a comparison of carcass recovery locations for 713 manatees killed by cold stress between 1999 and 2011 and the distribution of known refuges, it appears that springs offer manatees the best protection against cold stress. Long-term survival of Florida manatees will require improved efforts to enhance and protect manatee access to and use of warm-water springs as power plant outfalls are shut down.

Fatty acid signature analysis (FASA) is an important tool by which marine mammal scientists gain insight into foraging ecology. Fatty acid profiles (resulting from FASA) represent a potential biomarker to assess exposure to natural and anthropogenic stressors. Florida manatees are well studied, and an excellent necropsy program provides a basis against which to assess this budding tool. Results using samples from 54 manatees assigned to four cause-of-death categories indicated that those animals exposed to or that died due to brevetoxin exposure (red tide, or RT samples) demonstrate a distinctive hepatic fatty acid profile. Discriminant function analysis indicated that hepatic fatty acids could be used to classify RT versus non-RT liver samples with reasonable certainty. A discriminant function was derived based on 8 fatty acids which correctly classified 100% of samples from a training dataset (10 RT and 25 non-RT) and 85% of samples in a cross-validation dataset (5 RT and 13 non-RT). Of the latter dataset, all RT samples were correctly classified, but two of thirteen non-RT samples were incorrectly classified. However, the "incorrect" samples came from manatees that died due to other causes during documented red tide outbreaks; thus although the proximal cause of death was due to watercraft collisions, exposure to brevetoxin may have affected these individuals in ways that increased their vulnerability. This use of FASA could: a) provide an additional forensic tool to help scientists and managers to understand cause of death or debilitation due to exposure to red tide in manatees; b) serve as a model that could be applied to studies to improve assessments of cause of death in other marine mammals; and c) be used, as in humans, to help diagnose metabolic disorders or disease states in manatees and other species., (Copyright © 2010 Elsevier B.V. All rights reserved.)

Knowledge of mammalian diversity is still surprisingly disparate, both regionally and taxonomically. Here, we present a comprehensive assessment of the conservation status and distribution of the world's mammals. Data, compiled by 1700+ experts, cover all 5487 species, including marine mammals. Global macroecological patterns are very different for land and marine species but suggest common mechanisms driving diversity and endemism across systems. Compared with land species, threat levels are higher among marine mammals, driven by different processes (accidental mortality and pollution, rather than habitat loss), and are spatially distinct (peaking in northern oceans, rather than in Southeast Asia). Marine mammals are also disproportionately poorly known. These data are made freely available to support further scientific developments and conservation action.

The double pulsar system PSR J0737-3039A/B is unique in that both neutron stars are detectable as radio pulsars. They are also known to have much higher mean orbital velocities and accelerations than those of other binary pulsars. The system is therefore a good candidate for testing Einstein's theory of general relativity and alternative theories of gravity in the strong-field regime. We report on precision timing observations taken over the 2.5 years since its discovery and present four independent strong-field tests of general relativity. These tests use the theory-independent mass ratio of the two stars. By measuring relativistic corrections to the Keplerian description of the orbital motion, we find that the "post-Keplerian" parameter s agrees with the value predicted by general relativity within an uncertainty of 0.05%, the most precise test yet obtained. We also show that the transverse velocity of the system's center of mass is extremely small. Combined with the system's location near the Sun, this result suggests that future tests of gravitational theories with the double pulsar will supersede the best current solar system tests. It also implies that the second-born pulsar may not have formed through the core collapse of a helium star, as is usually assumed.

The position, porosity and oil-filled nature of the zygomatic process of the squamosal bone (ZPSB) of the Florida manatee, Trichechus manatus latirostris, suggest that it may have a similar sound conduction function to that of the intramandibular fat body (IMFB) of the bottlenose dolphin, Tursiops truncatus, and other odontocetes. To examine this possibility we determined the lipid composition of the ZPSB and adipose tissue from the dorsal part of the head region of the Florida manatee, and compared it to that of the dolphin IMFB and melon (another fatty area implicated in sound conduction in odontocetes). Lipids from manatee ZPSB and from adipose tissue were composed almost entirely of triacylglycerols. The most abundant fatty acids of the ZPSB were 18:1, 16:0, 14:0 and 16:1. The major fatty acids of the adipose tissue in the head were the four mentioned above, along with 12:0 and 18:0. Manatee samples did not contain isovaleric acid (iso-5:0), which was found in the bottlenose dolphin IMFB and melon, and has been related to sound conduction in dolphins and some other odontocetes. Thus, if manatee tissues are capable of sound conduction, and this process does occur through the ZPSB, a somewhat different suite of lipid components must support this function.

Relative to many other mammals, little is known about the functional morphology of the four extant species of the order Sirenia. In this study, 166 Florida manatee (Trichechus manatus latirostris) carcasses fresh enough to collect detailed anatomical information were examined to describe the gross anatomy of the diaphragm. Our results show that the Florida manatee's diaphragm differs from those of other mammals in that it: lies in a dorsal plane, rather than in the more typical transverse plane; is located dorsal to the heart and does not attach to the sternum; and attaches medially at the "I"-shaped central tendon to bony projections extending ventrally from the vertebral bodies, forming two distinct hemidiaphragms. The manatee's transverse septum is a separate structure that lies at a right angle to the diaphragm and separates the heart from the liver and other viscera. The extreme muscularity of the diaphragm and the ability of manatees to adjust their position in the water column with minimal external movement suggest that diaphragmatic contractions may change the volume of each pleural cavity to affect buoyancy, roll, and pitch. We also hypothesize that such contractions, in concert with contractions of powerful abdominal muscles, may compress gas in the massive large intestine, and thereby also contribute to buoyancy control., (Copyright 2000 Wiley-Liss, Inc.)

Study Objective: To establish the analgesic effective doses as defined as a visual analog pain scale (VAS) of at least 10 for 95% of parturients (ED95) receiving either epidural fentanyl or sufentanil with bupivacaine 0.125% for labor analgesia., Design: Double-blind, randomized controlled study., Setting: Two tertiary-care teaching hospitals., Patients: 100 female patients, at full-term pregnancy, in active early labor (< 5 cm cervical dilation) and requesting obstetric anesthesia services for labor analgesia., Interventions: Patients were randomized and equally distributed to receive one of ten epidural dosing regimens of bupivacaine 0.125% alone or with either fentanyl 25, 50, 75, or 100 micrograms or sufentanil 5, 10, 15, 20, or 25 micrograms in a 10-ml bolus after a 3-ml test dose of bupivacaine 0.25%., Measurements and Main Results: VAS scores were obtained from each parturient using a 10-cm plastic VAS slide rule at times 0, 1, 5, 10, 15, 20, 25, and 30 minutes, and then again when the patient requested additional analgesia. Analgesic duration and demographic and obstetric data also were obtained. Using a log-probit dose-response analysis, analgesic success as defined as a VAS of at least 10 with each opioid dose was plotted and an ED95 value of 8 micrograms and 50 micrograms was established for sufentanil and fentanyl, respectively, in bupivacaine 0.125%. No statistical difference was detected for analgesic duration or incidence of side effects between analgesic groups., Conclusions: Epidural analgesia with fentanyl and sufentanil in bupivacaine 0.125% behaves in a dose-response fashion allowing for the determination of equipotent dose of each.

We assess population trends of the Atlantic coast population of Florida manatee, Trichechus manatus latirostris, by reanalyzing aerial survey data collected between 1982 and 1992. To do so, we develop an explicit biological model that accounts for the method by which the manatees are counted, the mammals' movement between surveys, and the behavior of the population total over time. Bayesian inference, enabled by Markov chain Monte Carlo, is used to combine the survey data with the biological model. We compute marginal posterior distributions for all model parameters and predictive distributions for future counts. Several conclusions, such as a decreasing population growth rate and low sighting probabilities, are consistent across different prior specifications.

Apoptosis occurs during development and tissue homeostasis, and under conditions of physical and chemical stress. During apoptosis, cells digest their DNA, decrease intracellular pH, shrink, exhibit protein phosphatase activity, and activate members of the ICE/CED-3 family of proteases. This protease activity is identified by cleavage of poly(ADP-ribose) polymerase (PARP). Phosphatase activity during apoptosis is observed as dephosphorylation of the retinoblastoma susceptibility protein (Rb). Serine/threonine phosphatase inhibitors can prevent dephosphorylation of Rb and apoptosis, suggesting that Rb dephosphorylation is an indication of a critical regulator of apoptosis. The experiments described here were designed to establish the temporal relationship between these events. Apoptosis was induced in human ML-1 cells by the topoisomerase inhibitor etoposide. An inhibitor of the ICE/CED-3 protease family, z-VAD-fluoromethylketone (FMK), showed concentration-dependent protection from PARP cleavage, intracellular acidification, DNA digestion, early changes in membrane permeability, and cell shrinkage, thereby placing all of these events downstream of the ICE/CED-3 protease action. However, z-VAD-FMK did not prevent the dephosphorylation of Rb, placing this change upstream of the protease. These results suggest that the imbalance between protein phosphatase and kinase that is responsible for the dephosphorylation of Rb is also responsible for the activation of ICE/CED-3 proteases, which in turn is responsible for all the other events associated with apoptosis.

Intracellular acidification appears to be a frequent and possibly universal occurrence during apoptosis. We have used carboxy SNARF-1 to measure intracellular pH by flow cytometry. We report here that the addition of Hoechst 33342 concurrently with carboxy SNARF-1 provides a clearer discrimination of the apoptotic population. Apoptotic cells accumulate Hoechst 33342 more rapidly than do viable nonapoptotic cells. The cells with greater Hoechst 33342 fluorescence are the same cells as those with decreased intracellular pH; these cells also have decreased volume. The different parameters in this analysis are presented for three models of apoptosis: human myeloblastoid ML-1 cells incubated with etoposide, murine cytotoxic T cells following withdrawal of interleukin-2, and Chinese hamster ovary cells incubated with staurosporine. In most circumstances, carboxy SNARF-1 provides excellent resolution of viable and apoptotic cells. However, the addition of Hoechst 33342 is particularly valuable when carboxy SNARF-1 alone can not fully discriminate the two cell populations. This situation occurs in Chinese hamster ovary cells, which undergo a smaller degree of acidification than do the other cell models. This situation also occurs when the extracellular pH is experimentally reduced to investigate the mechanism of pH dysregulation; the apoptotic cells appear to retain the ability to regulate intracellular pH at low pH, although they are defective in proton export at neutral pH.

The ability of Bcl-2 to inhibit cell death is well documented but its mechanism of action remains elusive. Recent reports have suggested that Bcl-2 prevents apoptosis by inhibiting the release of Ca2+ from the thapsigargin-sensitive Ca2+ store. The mobilization of Ca2+ from this store has been implicated as a signal regulating apoptotic cell death induced by glucocorticoids and by interleukin-3 withdrawal. The present study was designed to determine if Bcl-2 would still inhibit apoptosis after depletion of intracellular Ca2+ stores. We compared the response of two Chinese hamster ovary cell lines (5AHSmyc and 5A300bcl-2.2) following incubation with the calcium ionophore ionomycin to deplete intracellular Ca2+ stores. Continued incubation of 5AHSmyc cells in calcium-free media induced substantial apoptotic DNA fragmentation within 4 h and >95% loss of viability within 48 h. However, 5A300bcl-2.2 cells showed no evidence of DNA fragmentation or loss of viability over the same time period. Intracellular Ca2+ was analyzed with the Ca2+-sensitive fluorescent dye INDO-1 and confirmed that ionomycin was capable of releasing Ca2+ from intracellular stores in both cell lines. These results show that depletion of intracellular Ca2+ stores induces apoptosis and that these Ca2+ stores are not required for the protection afforded by Bcl-2.

Hepatitis C viral (HCV) RNA includes an internal ribosome entry segment (IRES) that extends some 30 nt into the coding region and promotes internal initiation of translation at the authentic initiation codon at nt 342. The 5'-boundary of this IRES was mapped by in vitro translation and transfection assays and was found to lie between nt 42 and 71. Within these IRES boundaries there are, in most HCV strains, three AUG triplets upstream of the authentic initiation site. Although the first, 5'-proximal, of these is absolutely conserved, a mutational analysis showed that it is not a functional initiation codon. In particular, the G residue could be substituted provided compensatory mutations were made to maintain base pairing. The other two upstream AUGs are not absolutely conserved, and mutation of the third (5'-distal) had little effect on IRES activity. When an additional AUG codon was introduced by single-site mutation just upstream of the authentic initiation codon, it was found to be used when most of the IRES had been deleted to generate an RNA translated by the scanning ribosome mechanism, but was not used in the background of the full-length IRES when internal initiation is operative. These results argue that the IRES promotes direct ribosome entry immediately at, or indeed very close to, the authentic initiation codon, and that the upstream AUGs do not serve as ribosome entry sites.

Many events in apoptosis have been identified but their temporal relationships remain obscure. Apoptosis in human ML-1 cells induced by etoposide is characterized by intracellular acidification, enhanced Hoechst 33342 fluorescence, DNA digestion, chromatin condensation, and proteolysis of poly(ADP-ribose) polymerase. This proteolysis is a marker for the action of ICE/CED-3 proteases, which are critical activators of apoptosis. We observed that three serine/threonine protein phosphatase inhibitors, okadaic acid, calyculin A, and cantharidin, prevented all of these apoptotic characteristics. To determine which protein phosphatase was involved, we investigated the dephosphorylation of the retinoblastoma susceptibility protein Rb, a substrate for protein phosphatase 1 but not protein phosphatase 2A. Rb was dephosphorylated during apoptosis, and each inhibitor prevented this dephosphorylation at the same concentrations that prevented apoptosis. No increase in protein phosphatase 1 activity was observed in apoptotic cells suggesting that dephosphorylation of Rb may result from loss of Rb kinase activity in the presence of a constant level of protein phosphatase activity. Long term inhibition of protein phosphatase 1 (>8 h) also led to the appearance of dephosphorylated Rb, cleavage of poly(ADP-ribose) polymerase and apoptosis, suggesting these events are not solely dependent upon protein phosphatase 1. Rb dephosphorylation was also observed in several other models of apoptosis. Hence, an imbalance between protein phosphatase 1 and Rb kinase may be a common means to activate ICE/CED-3 proteases resulting in the subsequent events of apoptosis.

Background: The Florida manatee, Trichechus manatus latirostris (Sirenia: Trichechidae), is the largest herbivorous marine mammal. Previously, components of the gastrointestinal (GI) tract of the species have been described, but no comprehensive descriptions of the gross and microscopic anatomy existed. This study integrates function and structure of the entire Florida manatee GI tract., Methods: The GI tracts of several recently dead Florida manatees were examined from the following viewpoints: gross anatomical studies of preserved and unpreserved specimens, histology and histochemistry, and ultrastructure., Results: The manatee GI tract has an enlarged hindgut, as do other nonruminant herbivores (i.e., hindgut digesters such as horses), but it also has important adaptations not seen in most other mammals. These structural adaptations include a discrete accessory digestive gland (the cardiac gland), submucosal mucous glands along the greater curvature of the stomach, and unkeratinized, stratified squamous epithelial cells overlying the glandular mucosae of the pyloric antrum, midgut cecum, colon, and rectum., Conclusions: The adaptations described above may relate to osmoregulation as well as to herbivory. The Florida manatee GI tract is most similar to those of other members of the Order Sirenia and to that of the herbivorous green sea turtle (Chelonia mydas), but it also shows superficial similarities to those of phylogenetically close Orders, the Proboscidea and Hyracoidea. The immense size of both the manatee and its large intestine suggests that, relative to smaller hindgut digesters, manatees have a slow rate of passage of digesta and efficient breakdown of fibrous plant material.

Multiple physiological and pharmacological stimuli induce cells to die by apoptosis. In many cases, this apoptosis is inhibited by BCL-2, suggesting the involvement of a common regulatory pathway. One frequent characteristic of apoptosis is the digestion of DNA into oligonucleosome-length fragments. Intracellular acidification and increased intracellular calcium have been variously implicated in activating the endonuclease responsible for this DNA digestion. To explore the involvement of these potential signals in endonuclease activation, we have analyzed three Chinese hamster ovary cell lines: a parental line, one expressing a cDNA encoding BCL-2, and the third expressing the BCL-2 family member MCL-1. Apoptosis was induced with the protein kinase inhibitor staurosporine and intracellular pH and calcium were measured by flow cytometry. We found that both MCL-1 and BCL-2 inhibited DNA digestion compared to the parent cell line, although BCL-2 was more potent in this regard. Concurrent with DNA digestion, we observed intracellular acidification; MCL-1 and BCL-2 inhibited intracellular acidification to an extent commensurate with their ability to inhibit DNA digestion. In contrast, staurosporine caused a dose-dependent increase in intracellular calcium in all three cell lines, demonstrating that intracellular free calcium levels did not correlate with the induction of apoptosis. These results suggest that BCL-2 and MCL-1 may regulate a pathway for intracellular pH homeostasis during apoptotic cell death.

We used segregation analysis to investigate the genetic basis of variation in dystopia canthorum, one of the key diagnostic features of Waardenburg syndrome type 1 (WS1). We sought to determine whether the W-index, a quantitative measure of this craniofacial feature, is influenced primarily either by allelic variation in the PAX3 disease gene or other major loci, by polygenic background effects, or by all of these potential sources of genetic variation. We studied both WS1-affected individuals and their WS1-unaffected relatives. After adjustment of the W-index for WS1 disease status, segregation analyses by the regression approach indicated major-locus control of this variation, although residual parent-offspring and sib-sib correlations are consistent with additional (possibly polygenic) effects. Separate analyses of WS1-affected and WS1-unaffected individuals suggest that epistatic interactions between disease alleles at the PAX3 WS1 locus and a second major locus influence variation in dystopia canthorum. Our approach should be applicable for assessing the genetic architecture of variation associated with other genetic diseases.

We present a series of 8.4-GHz very-long-baseline radio interferometry images of the nucleus of Centaurus A (NGC5128) made with a Southern Hemisphere array, representing a 3.3-year monitoring effort. The nuclear radio jet is approximately 50 milliarcseconds in extent, or at the 3.5-megaparsec distance of NGC5128, approximately 1 parsec in length. Subluminal motion is seen and structural changes are observed on time scales shorter than 4 months. High-resolution observations at 4.8 and 8.4 GHz made in November 1992 reveal a complex morphology and allow us to unambiguously identify the self-absorbed core located at the southwestern end of the jet.