Morphology and function of the forelimb in arboreal frogs: specializations for grasping ability.

Frogs are characterized by a unique morphology associated with their saltatory lifestyle. Although variation in the form and function of the pelvic girdle and associated appendicular system related to specialized locomotor modes such as swimming or burrowing has been documented, the forelimbs have typically been viewed as relatively unspecialized. Yet, previous authors have noted versatility in forelimb function among arboreal frogs associated with feeding. Here we study the morphology and function of the forelimb and hand during locomotion in two species of arboreal frogs (Litoria caerulea and Phyllomedusa bicolor). Our data show a complex arrangement of the distal forelimb and hand musculature with some notable differences between species. Analyses of high‐speed video and video fluoroscopy recordings show that forelimbs are used in alternating fashion in a diagonal sequence footfall pattern and that the position of the hand is adjusted when walking on substrates of different diameters. Electromyographic recordings show that the flexors of the hand are active during substrate contact, suggesting the use of gripping to generate a stabilizing torque. Measurements of grasping forces in vivo and during stimulation experiments show that both species, are capable of executing a so‐called power grip but also indicates marked differences between species, in the magnitude of forces generated. Stimulation experiments showed an increased control of digit flexion in the more specialized of the two species, allowing it to execute a precision grip paralleled only by that seen in primates.Fil: Manzano, Adriana Silvina. Provincia de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Universidad Autónoma de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción; ArgentinaFil: Abdala, Virginia Sara Luz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biodiversidad Neotropical. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Instituto de Biodiversidad Neotropical. Instituto de Biodiversidad Neotropical; ArgentinaFil: Herrel, Anthony. University of Antwerp; Bélgic

KSU Chamber Singers, A Litany for Courage and the Seasons

Kennesaw State University Chamber Singers present David Maslanka\u27s A Litany for Courage and the Seasons, six songs for chorus, clarinet and vibraphone on poems of Richard Beale at the 2013 National Collegiate Choral Organization 5th National Conference in Charleston, South Carolina, October 31 - November 2.https://digitalcommons.kennesaw.edu/musicprograms/1268/thumbnail.jp

KSU Chamber Singers and Men\u27s Ensemble

KSU School of Music presents KSU Chamber Singers and Men\u27s Ensemble.https://digitalcommons.kennesaw.edu/musicprograms/1294/thumbnail.jp

Holiday Concert, Home for the Holidays

Kennesaw State University School of Music presents Holiday Concert, Home for the Holidays.https://digitalcommons.kennesaw.edu/musicprograms/1433/thumbnail.jp

American Choral Directors Association Preview Concert with Guest Artist Ola Gjeilo, composer

Kennesaw State University School of Music presents the ACDA National Conference American Choral Directors Association Preview Concert with guest artist Ola Gjeilo, composer.https://digitalcommons.kennesaw.edu/musicprograms/1337/thumbnail.jp

Customising virtual globe tours to enhance community awareness of local landscape benefits

Our wellbeing depends upon the services provided by ecosystems and their components. Despite recent advances in academic understanding of ecosystem services, and consideration in UK national environmental policy, a greater awareness is needed at community and individual levels. Dynamic features of virtual globe applications have considerable potential for helping convey the multi-dimensional context of ecosystem services and promoting general awareness. In a case study targeting residents in a small urban fringe river catchment in Norfolk, UK, representatives from local authorities and responsible agencies collaborated with scientists to produce extensive customisation of virtual globes in this context. By implementing a virtual flight over the catchment, different views and scales are traversed to set the context for landscape features and ecosystem services. Characteristic sites, e.g. supplying cultural services, are displayed and relationships with the natural environment are explained using linked on-screen text. Implementation is cost-effective and described for practitioners in ecosystem and landscape management, who may be inexperienced in landscape visualisation. Supplied as three pre-packaged virtual tours, products are made available for download and are publicised at a variety of engagement events, including teaching events with schoolchildren. The tours have attracted public interest and generated positive feedback about improving knowledge of local natural assets. Schoolchildren show confidence with the interface, but supplementary problem-based activities can improve learning opportunities. The capacity of virtual globes to support more participatory involvement of the public in local ecosystem management may increase in the future, but such visualisations can already help promote community awareness of local landscape benefits

Setting the stage: host invasion by HIV.

For more than two decades, HIV has infected millions of people worldwide each year through mucosal transmission. Our knowledge of how HIV secures a foothold at both the molecular and cellular levels has been expanded by recent investigations that have applied new technologies and used improved techniques to isolate ex vivo human tissue and generate in vitro cellular models, as well as more relevant in vivo animal challenge systems. Here, we review the current concepts of the immediate events that follow viral exposure at genital mucosal sites where most documented transmissions occur. Furthermore, we discuss the gaps in our knowledge that are relevant to future studies, which will shape strategies for effective HIV prevention

Adoption of an “Open” Envelope Conformation Facilitating CD4 Binding and Structural Remodeling Precedes Coreceptor Switch in R5 SHIV-Infected Macaques

A change in coreceptor preference from CCR5 to CXCR4 towards the end stage disease in some HIV-1 infected individuals has been well documented, but the reasons and mechanisms for this tropism switch remain elusive. It has been suggested that envelope structural constraints in accommodating amino acid changes required for CXCR4 usage is an obstacle to tropism switch, limiting the rate and pathways available for HIV-1 coreceptor switching. The present study was initiated in two R5 SHIVSF162P3N-infected rapid progressor macaques with coreceptor switch to test the hypothesis that an early step in the evolution of tropism switch is the adoption of a less constrained and more “open” envelope conformation for better CD4 usage, allowing greater structural flexibility to accommodate further mutational changes that confer CXCR4 utilization. We show that, prior to the time of coreceptor switch, R5 viruses in both macaques evolved to become increasingly sCD4-sensitive, suggestive of enhanced exposure of the CD4 binding site and an “open” envelope conformation, and this correlated with better gp120 binding to CD4 and with more efficient infection of CD4low cells such as primary macrophages. Moreover, significant changes in neutralization sensitivity to agents and antibodies directed against functional domains of gp120 and gp41 were seen for R5 viruses close to the time of X4 emergence, consistent with global changes in envelope configuration and structural plasticity. These observations in a simian model of R5-to-X4 evolution provide a mechanistic basis for the HIV-1 coreceptor switch