Natural Heritage Protection in the Driftess Area

The heavily dissected terrain of northeastern Iowa and adjacent parts of Minnesota, Illinois, and Wisconsin, historically known as the Driftless Area has an array of unusual or unique biotic, cultural, and geological amenities. As these features become better known, a greater awareness is emerging, as is a heightened concern for saving the outstanding examples of each community, culture, historical site, and geological feature. Each of the states has a natural area program and has developed a list of natural communities including those of the Driftless Area. Each state\u27s program relative to the Driftless Area is given, with emphasis on Iowa, and preservation needs for the future are delineated

Iowa Natural Heritage Preservation: History, Present Status, and Future Challenges

Iowa was blessed with an abundant and diverse natural heritage. The history of problems of preservation of natural areas to depict the types and diversity of original Iowa are presented in an historical framework. The history is divided into 3 eras: an era of settlement (1832-1900), an era of academic concern (1900-1950), and a contemporary era (1950-present). The contemporary era is subdivided into 3 periods: an organizational period (l 950-1965), a period of inactivity (l965-1975), and a period of renewed activity (l 975-present). Two general themes are apparent: (a) numerous plans have been formulated but never adequately implemented, and (b) much of the successes are directly attributable to the active efforts of a very few people. Pre-eminent among Iowa naturalists in preservation efforts are Thomas Macbride, Louis Pammel, Bohumil Shimek and Ada Hayden. Although a resurgence of natural history-related efforts is evident in the last 5 years, the magnitude of the work remaining and the uncertainty of how much time might be left for its implementation, necessitates all Iowa natural historians participate in a more active manner

Bibliography of Iowa Aquatic and Wetland Plant Literature

A bibliography of 350 references by 210 authors is presented. References were included if they treated the identity, floristics, taxonomy, ecology, physiology, wildlife interaction, limnological role, or historical importance of Iowa’s aquatic and wetland macrophytes. Some references were briefly annotated to clarify titles or support their inclusion in the bibliography

Exercise during growth provides lifelong benefit to bone structure and strength: a case study

poster abstractExercise induces greatest gains in bone health during skeletal development, yet reduced bone strength is predominantly an age-related phenomenon. This dichotomy has raised the question of whether exercise-induced changes in bone health when young persist into late adulthood where they may have benefits on bone health and fracture risk. Previous work has suggested exercise-induced gains in bone mass are lost with aging; however, 1) exercise during growth predominantly influences bone structure rather than mass to increase bone strength and 2) mechanisms exist for the long-term maintenance of exercise effects on bone structure. The aim of the current case was to explore whether exercise-induced gains in bone structure and strength accrued when young persist lifelong. The subject was a 94-year-old former Major League Baseball (MLB) pitcher who played competitively for 20 years before ceasing play in 1955. Throwing athletes are a unique model to investigate the skeletal effects of exercise as: 1) the unilateral upper extremity loading associated with throwing enables the contralateral side to serve as an internal control site and 2) throwing athletes have large dominant-to-nondominant (D-to-ND) differences in midshaft humeral bone properties. Peripheral quantitative computed tomography slices of the subject’s dominant and nondominant humerii were taken at 50% humeral length, and D-to-ND percent differences in bone properties calculated and compared to those observed previously in non-throwing controls. Exercise when young had no lasting effects on D-to-ND difference in cortical bone mass or area; however, Dto-ND difference in total area was nearly 3-times that observed in controls. The maintenance of exercise effects on total area resulted from persistence of benefits on periosteal perimeter, with the loss of cortical bone mass and area benefits being due to greater endosteal expansion (perimeter). As a result of the maintenance of exercise-induced benefits on bone structure, D-to-ND difference in ability to resist torsional forces (polar moment of inertia) was nearly double that observed due to habitual loading associated with arm dominance in controls. The maintenance of exercise-induced benefits on bone structure in the current case, despite exercise ceasing 56 years ago, supports the hypothesis that exercise when young can have lasting benefits on bone strength independent of maintenance of bone mass effects. This question is being further explored in a cohort of 100 former MLB players and 100 matched controls

Preserving Natural Diversity in Iowa\u27s Loess Hills: Challenges and Opportunities

The Loess Hills of western Iowa, due to their extent and depth, are of national importance for geological reasons. They also harbor a large portion of Iowa\u27s remaining biological diversity, the significance of which has been underscored by studies sponsored by the State Preserves Advisory Board during the past several years. A complex of rare species of plants and animals exist in the rugged terrain; many are Great Plains species which find their only Iowa stations in these Loess Hills. Management problems, such as rapid invasion of prairies by woody species, are manifest in this landform and must be addressed in the near future. Land protection measures are being addressed by the Department of National Resources, State Preserves Advisory Board, Iowa Natural Heritage Foundation, the Iowa Chapter of The Nature Conservancy and County Conservation Boards. The National Park Service has recently designated over 10,000 acres as a National Natural Landmark

Habitat and Distribution of Plants Special to Iowa\u27s Driftless Area

A portion of the Upper Midwest escaped glaciation during the two most recent glacial epochs. This Driftless Area , also known in Iowa as the Paleozoic Plateau , comprises some 39,000 square kilometers (15,000 square miles) in the states of Illinois, Iowa, Minnesota, and Wisconsin. Today the highly dissected terrain provides a variety of habitats supporting a rich and diverse flora including many plants special to the area, i.e., principally, in Iowa, restricted to the Driftless Area. These special plants have received much attention, often having been discussed as possible relicts from past floras. However, distribution data for these species beyond the Driftless Area has been compiled for only a few. We present habitat descriptions and mid-western (and North American where appropriate) distribution maps of 74 plant species special to the Iowa portion of the Driftless Area, along with speculation on their origin, with particular reference to late Quaternary events. The exceptional plant diversity and unusual species in the Driftless Area in Iowa result from a complex of factors which include the extreme habitat diversity, the location of the area near the juncture of three regional floras, river corridors which provide migrational pathways from other regional floras, and the relictual nature of a number of species

Systematic Comparison of Parameter Estimation Approaches Using the Generalized-growth Model for Prediction of Epidemic Outbreaks

Background- Many different mathematical models are used to assess and predict the outbreaks. The model is selected by the characteristics of the outbreaks. Here, we utilize the generalized growth model (GGM), one of the simplest mathematical models, with the real outbreaks to compare two parameter estimation methods. Materials and Methods- 25 outbreaks are used to analyze. We use GGM with the ascending phase of each outbreak and estimated the r and p parameters with both the least square (LSQ) and maximum likelihood estimation (MLE) methods. For both parameter estimation methods, we conduct the parametric bootstrap method to construct the confidence interval of parameters. We compare the two estimation methods by the RMSE, Anscombe residual, and prediction coverage. Results- The result shows that most outbreaks have similar r and p parameters, RMSE, Anscombe, and prediction coverage for LSQ and MLE. Although Anscombe values for LSQ are higher than the values for MLE, the difference between results of the two methods are minimal for the most outbreaks. Conclusion- The study is shown that LSQ and MLE do not result in different values of the parameter estimation, RMSE, Anscombe, and prediction coverage with GGM

A Checklist of the Vascular Flora of Allamakee County, Iowa

Based upon field and herbarium study, the vascular flora of Allamakee County is composed of 1040 taxa (species plus hybrids), including 46 endangered and 23 threatened Iowa species. This number represents approximately 50% of the species in the state flora and is the greatest number of taxa documented for a single Iowa county. The large and diverse flora reflects the diversity of topography and habitat types within the county. The study resulted in the addition of four taxa to the state flora (Conopholis americana, Dryopteris X triploidea, Equisetum X litorale, and Polygonum douglasii) and in the location of populations of two species previously considered extirpated within the state (Dryopteris intermedia and Ilex verticillata)

Regulatory Mechanisms in Bone Following Mechanical Loading

Bone responds with increased bone formation to mechanical loading, and the time course of bone formation after initiating mechanical loading is well characterized. However, the regulatory activities governing the loading-dependent changes in gene expression are not well understood. The goal of this study was to identify the time-dependent regulatory mechanisms that governed mechanical loading-induced gene expression in bone using a predictive bioinformatics algorithm. A standard model for bone loading in rodents was employed in which the right forelimb was loaded axially for three minutes per day, while the left forearm served as a non-loaded, contralateral control. Animals were subjected to loading sessions every day, with 24 hours between sessions. Ulnas were sampled at 11 time points, from 4 hours to 32 days after beginning loading. Using a predictive bioinformatics algorithm, we created a linear model of gene expression and identified 44 transcription factor binding motifs and 29 microRNA binding sites that were predicted to regulate gene expression across the time course. Known and novel transcription factor binding motifs were identified throughout the time course, as were several novel microRNA binding sites. These time-dependent regulatory mechanisms may be important in controlling the loading-induced bone formation process

Age-Related Changes in Proximal Humerus Bone Health in White Males

poster abstractThe proximal humerus is a common site for osteoporotic fracture during aging, accounting for up to 5% of fractures to the appendicular skeleton. While falls onto an outstretched hand are usually physically responsible for proximal humerus fractures, the ability of the underlying bone to resist applied loads must also play a role. Few studies have assessed proximal humerus bone health with aging. The aim of the current study was to explore age-related bone changes at the proximal humerus in men. A cross-sectional study design was used to assess peripheral quantitative computed tomography (pQCT)-derived bone properties of the proximal humerus in a cohort of 112 white males (age range = 30-85 yrs). A tomographic slice of the non-dominant upper extremity was acquired at 80% of humeral length proximal from its distal end—a location corresponding to the surgical neck of the humerus. Images were assessed for cortical (Ct.BMC) and trabecular (Tb.BMC) BMC, total (Tt.Ar), cortical (Ct.Ar) and medullary (Me.Ar) area, periosteal (Ps.Pm) and endosteal (Es.Pm) perimeter, cortical thickness (Ct.Th), and bone strength index for compression (BSIc). BSIc was calculated as the product of Tt.Ar and the square of total volumetric BMD. Data were plotted against age and linear regression lines assessed for their slope. Slopes were subsequently converted to percent change in the bone property per year. During aging, the proximal humerus expanded with Tt.Ar and Ps.Pm increasing at rates of 0.40%/yr and 0.19%/yr, respectively. However, Me.Ar (0.62%/yr) and Es.Pm (0.34%/yr) expanded at faster rates such that there was net loss of both Ct.BMC (-0.23%/yr) and Tb.BMC (-1.08%/yr). Also, the more rapid expansion of Me.Ar relative to Tt.Ar meant that Ct.Ar (-0.15%/yr) and Ct.Th (-0.34%/yr) both decreased with age. The net result of these mass and structural changes was progressive loss of bone strength with age, as indicated by a 0.44%/yr decline in BSIc. These data provide a picture of bone changes at the proximal humerus during aging. They suggest that between age 30 and 80 yrs, approximately 54% and 11% of Tb.BMC and Ct.BMC at the proximal humerus is lost, respectively. They also suggest that compressive strength of the proximal humerus declines by 22% between age 30 and 80 years. These declines in proximal humerus bone health have implications for fracture risk at this location during aging