Koinonia

Decision Making int he 90s: The Role of Intuition, Todd S. Voss ACSD 1991 National Conference Report Conference Photos & Quotes The Reflective Christian CoCCA: The Christian College Activities Index Position Changes President\u27s Cornerhttps://pillars.taylor.edu/acsd_koinonia/1043/thumbnail.jp

Plakophilin-3 Is Required for Late Embryonic Amphibian Development, Exhibiting Roles in Ectodermal and Neural Tissues

The p120-catenin family has undergone a significant expansion during the evolution of vertebrates, resulting in varied functions that have yet to be discerned or fully characterized. Likewise, members of the plakophilins, a related catenin subfamily, are found throughout the cell with little known about their functions outside the desmosomal plaque. While the plakophilin-3 (Pkp3) knockout mouse resulted in skin defects, we find larger, including lethal effects following its depletion in Xenopus. Pkp3, unlike some other characterized catenins in amphibians, does not have significant maternal deposits of mRNA. However, during embryogenesis, two Pkp3 protein products whose temporal expression is partially complimentary become expressed. Only the smaller of these products is found in adult Xenopus tissues, with an expression pattern exhibiting distinctions as well as overlaps with those observed in mammalian studies. We determined that Xenopus Pkp3 depletion causes a skin fragility phenotype in keeping with the mouse knockout, but more novel, Xenopus tailbud embryos are hyposensitive to touch even in embryos lacking outward discernable phenotypes, and we additionally resolved disruptions in certain peripheral neural structures, altered establishment and migration of neural crest, and defects in ectodermal multiciliated cells. The use of two distinct morpholinos, as well as rescue approaches, indicated the specificity of these effects. Our results point to the requirement of Pkp3 in amphibian embryogenesis, with functional roles in a number of tissue types

Seasonal differences of corticosterone metabolite concentrations and parasite burden in northern bald ibis (Geronticus eremita): The role of affiliative interactions

The reproductive season is energetically costly as revealed by elevated glucocorticoid concentrations, constrained immune functions and an increased risk of infections. Social allies and affiliative interactions may buffer physiological stress responses and thereby alleviate associated effects. In the present study, we investigated the seasonal differences of immune reactive corticosterone metabolite concentrations, endoparasite burden (nematode eggs and coccidian oocysts) and affiliative interactions in northern bald ibis (Geronticus eremita), a critically endangered bird. In total, 43 individually marked focal animals from a freeranging colony were investigated. The analyses included a description of initiated and received affiliative interactions, pair bond status as well as seasonal patterns of hormone and endoparasite levels. During the reproductive season, droppings contained parasite eggs more often and corticosterone metabolite levels were higher as compared to the period after reproduction. The excretion rate of endoparasite products was lower in paired individuals than in unpaired ones, but paired animals exhibited higher corticosterone metabolite concentrations than unpaired individuals. Furthermore, paired individuals initiated affiliative behaviour more frequently than unpaired ones. This suggests that the reproductive season influences the excretion patterns of endoparasite products and corticosterone metabolites and that affiliative interactions between pair partners may positively affect endoparasite burden during periods of elevated glucocorticoid levels. Being embedded in a pair bond may have a positive impact on individual immune system and parasite resistance

Maternal Wnt/β-Catenin Signaling Coactivates Transcription through NF-κB Binding Sites during Xenopus Axis Formation

Maternal Wnt/β-Catenin signaling establishes a program of dorsal-specific gene expression required for axial patterning in Xenopus. We previously reported that a subset of dorsally expressed genes depends not only on Wnt/β-Catenin stimulation, but also on a MyD88-dependent Toll-like receptor/IL1-receptor (TLR/IL1-R) signaling pathway. Here we show that these two signal transduction cascades converge in the nucleus to coactivate gene transcription in blastulae through a direct interaction between β-Catenin and NF-κB proteins. A transdominant inhibitor of NF-κB, ΔNIκBα, phenocopies loss of MyD88 protein function, implicating Rel/NF-κB proteins as selective activators of dorsal-specific gene expression. Sensitive axis formation assays in the embryo demonstrate that dorsalization by Wnt/β-Catenin requires NF-κB protein activity, and vice versa. Xenopus nodal-related 3 (Xnr3) is one of the genes with dual β-Catenin/NF-κB input, and a proximal NF-κB consensus site contributes to the regional activity of its promoter. We demonstrate in vitro binding of Xenopus β-Catenin to several XRel proteins. This interaction is observed in vivo upon Wnt-stimulation. Finally, we show that a synthetic luciferase reporter gene responds to both endogenous and exogenous β-Catenin levels in an NF-κB motif dependent manner. These results suggest that β-Catenin acts as a transcriptional co-activator of NF-κB-dependent transcription in frog primary embryonic cells

Importance of residual trees to birds in regenerating pine plantations

Pine plantation establishment methods can alter vegetation composition and structure, thus affecting habitat important characteristics for declining early successional bird species. We evaluated eight vegetation characteristics, which varied due to a range of pine plantation establishment methods, to identify vegetation most closely associated with spring bird abundance in the Lower Coastal Plain of southern Mississippi, USA. Presence of residual trees and snags was positively related to relative abundance of 10 of 14 common species present in regenerating stands. Cover of woody vegetation was positively related to relative abundance of 4 species and negatively related to relative abundance of 2 species. For 5 species, increasing pine tree cover had a nega­tive relationship with relative abundance. Residual trees and snags contributed to avian abundance and richness in regenerating pine plantations. Integration of habitat elements, such as residual trees that influence abundance of birds and other wildlife, with intensive pine plantation establishment can aid mana­gers to attain wildlife conservation in intensively managed stands

Physical development of orphaned white-tailed deer fawns in southern Texas

The effect of doe harvest on the physical development of orphaned fawns is an important unanswered question in white-tailed deer management. Twenty-seven white-tailed deer (Odocoileus virginianus) fawns were captured, fitted with telemetry collars, and released in southern Texas during 15-16 October 1985. Three fawns died from capture-related trauma. Thirteen of the remaining 24 fawns were orphaned during 15 October-8 November 1985. Eleven fawns remained with their dams as controls. Surviving animals were collected 9-10 October 1986. Covariate-adjusted eviscerated carcass weight was lower (P = 0.08) for orphaned females (mean = 28.3 kg) than for control females (mean 32.4 kg). Two of 4 orphaned females bred as fawns compared to 0 of 5 control females. Metabolic demands associated with lactation could account for the lower eviscerated carcass weight and weight gain of orphaned females. Physical development of males was not affected by dam harvest (P>0.10). We conclude that in good quality habitat there are minimal, if any, negative effects of dam removal on physical development of surviving fawns.This material was digitized as part of a cooperative project between the Society for Range Management and the University of Arizona Libraries.The Journal of Range Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform August 202

Technical Note: Mineral content of guajillo regrowth following roller chopping

Guajillo (Acacia berlandieri Benth.) is browsed by white-tailed deer (Odocoileus virginianus Raf.). We determined phosphorus (P), potassium, (K), calcium (Ca), and magnesium (Mg) of browse from roller-chopped (July 1986 and July 1987) and nontreated guajillo. Browse from regrowth was temporarily higher in P than browse from nontreated plants. Potassium was higher in leaves from plants roller chopped in 1987. Calcium and Mg tended to be lower in leaves from roller-chopped plants. Roller chopping temporarily increases P and K, but whether or not browse from roller-chopped guajillo meets P and K requirements for deer is unknown.This material was digitized as part of a cooperative project between the Society for Range Management and the University of Arizona Libraries.The Journal of Range Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform August 202

Combining animal interactions and habitat selection into models of space use: a case study with white‐tailed deer

Animals determine their daily movement trajectories in response to a network of ecological processes, including interactions with other organisms, their memories of previous events, and the changing environment. These combine to cause the emergent space use patterns observed over longer periods of time, such as a whole season. Understanding which processes cause these patterns to emerge, and how, requires a process-based modelling approach. Individual-based decisions can be described as a system of partial-differential equations (PDEs) to produce a dynamic description of space use built from the underlying movement process. Here we combine PDE-based models with step-selection analysis to investigate the combined effects of three established ecological processes that partially shape movement and space use: 1) a heterogeneous environment; 2) the environmental markings of moving conspecifics; and 3) the memory of direct interactions with conspecifics. We apply this framework to a large GPS-based dataset of white-tailed deer Odocoileus virginianus in the southeastern US. We fit models at the population level to provide predictive models, then tailor these to fit individual deer. We specifically incorporate relationships between each possible pair of deer and define each animal's responses to their unique local environments using separate integrated step-selection analyses. We show how individual movements and decisions yield emergent patterns in animal distributions, and we provide a full generalised description of the framework so that it may be applied to any species simultaneously responding to multiple potentially interacting stimuli (e.g. sociality, morphology, etc.). We found that the population of bucks had highly varied preferences for vegetation, but were shaping their space use in response to conspecific interactions, dependent on the individual relationships between two deer. We advocate for increased consideration of individual-based movement rules as determinants of realized animal space use, and particularly how these affect emergent distributions of entire species

Vegetation characteristics influencing site selection by male white-tailed deer in Texas

We studied the effects of vegetation characteristics in southern Texas on site selection by mature, male white-tailed deer (Odocoileus virginianus Raf.). Thirteen, radio-collared animals were monitored during winter, spring, summer, and fall of 1986-87 and 1987-88 to determine area-usage patterns within each animal's respective seasonal home range. After each season, structural vegetation attributes were measured with transect-oriented data collection techniques inside the most heavily used and unused areas of each animal's home range. Comparisons were made between these areas to determine whether site selection by deer was in response to differing vegetation characteristics. In general, the most heavily used areas possessed a greater amount of woody canopy cover (greater than or equal to 85%), woody species richness (18-20), and horizontal screening cover than areas with no use. In contrast, herbaceous densities did not differ between the most heavily used and unused areas. Consequently, habitat management manipulations conducted specifically for mature male white-tailed deer in southern Texas, should include provisions for creation or maintenance of sites possessing dense woody canopy cover, a high number of woody species and dense horizontal screening cover.This material was digitized as part of a cooperative project between the Society for Range Management and the University of Arizona Libraries.The Journal of Range Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform August 202