Year-round and Migratory Birds of the Flint Hills

The Flint Hills support a wide diversity of birds. with some 250 species having been recorded. They range in size from the Ruby-throated Hummingbird (3 grams) to the 10-kg Wild Turkey. Birds tend to specialize by habitat, and each habitat---be it tallgrass prairie, shrublands, riparian forest, cropland, or farmstead---supports its own assemblage of bird species

Floral Neighborhood and Pollination Success in Four Hummingbird-Pollinated Cloud Forest Plant Species

In a cloud forest at Monteverde, Costa Rica, was examined pollen loads received by self—compatible flowers of two pairs of plant species pollinated by hummingbirds: Hansteinia blepharorachis and Razisea spicata (Acanthaceae), and Besleria triflora and Drymonia rubra (Gesneriaceae). Each pair consisted of one species (Hansteinia or Besleria) pollinated by short—billed hummingbirds and a related species (Razisea or Drymonia) pollinated by long—billed hummingbirds. At three different times per species, separated by 1—3 mo, we examined flowers on 28—40 focal plants from a wide variety of floral neighborhoods, ranging from plants isolated from conspecifics, either by distance or by other flowering species pollinated by the same hummingbirds, to plants surrounded by conspecifics. Because short—billed hummingbirds often restrict foraging to areas of high flower density, and because short—tubed flowers adapted for hummingbirds often have similar pollen placement, we predicted that short—tubed flowers isolated from conspecifics would receive fewer conspecific grains and more heterospecific grains than short—tubed flowers surrounded by conspecifics. Because long—billed hummingbirds often forage over large areas and because long—tubed flowers adapted for hummingbirds tend to diverge in pollen placement, we predicted that pollination of long—tubed flowers would be relatively unaffected by floral neighborhood. Effects on pollen loads of floral neighborhood (nearness to or isolation from other flowers) followed few patterns consistent with our prediction or with conventional theory. (1) There were no consistent effects of floral neighborhoods on numbers of heterospecific grains deposited on stigmas; in all four species, regardless of corolla length, effects of particular neighborhood variables (as determined with stepwise multiple regression) were as likely to run exactly counter to conventional models as to corroborate models. (2) In none of the 12 sampling runs did increases in absolute densities of neighboring heterospecific flowers adversely affect pollination. (3) However, in two runs, loads of conspecific grains increased with increases in the absolute density of neighboring conspecific flowers, and/or (in three runs) with increases in their relative density (proportion of conspecifics among neighboring flowers). These runs all involved short—flowered species rather than long—flowered species, tending confirm our initial prediction, but half the sampling runs, even of short—flowered species, failed to show any density—dependent effects from neighboring flowers pollinated by the same hummingbirds. Flowers frequently received fewer conspecific grains than they had ovules to be fertilized. Therefore the potential existed for floral neighborhoods to affect seed set and fitness of plants. Nevertheless, even though neotropical hummingbird—pollinated flowers have been cited as examples of species whose flowering peaks are displaced through competition for pollination, competitive effects from neighboring heterospecific plants were only sporadic in the species we examined, and were particularly infrequent in those species with long flowers adapted for long—billed hummingbirds

Disturbance, Pollinator Predictability, and Pollination Success Among Costa Rican Cloud Forest Plants

Cloud forest at Monteverde, Costa Rica experiences frequent natural disturbance. To determine whether species interactions vary spatially due to physical heterogeneity produced by disturbance, we examined relationships between 22 plant species and 11 nectar—feeding bird species in 14 study plots distributed among three patch types: larger landslide—like gaps (hand—cleared areas along a trail), small gaps (formed by recent treefalls), and understory of closed—canopy forest. Species we describe here flowered in two or three patch types. The aspects of pollination we examined varied little with patch type. Mean frequency of pollinator visits varied with patch type in a few plant species but not in most, and there was no significant trend across species. Pollen loads carried by 314 mist—netted hummingbirds did not vary significantly with patch type, either in total number of grains or number of species represented. Cumulative pollen loads that hummingbirds deposited on stigmas of two species of Acanthaceae (Razisea spicata and Hansteinia blepharorachis) did not vary consistently with patch type, except that Hansteinia flowers in treefall gaps received fewer heterospecific pollen grains than flowers in the other two patch types. Frequency of fruit set varied significantly with patch type in three of the four species examined, but the direction of variation in one of these was opposite to the direction of the other two. The absolute frequency with which flowers were pierced by nectar—robbing hummingbirds did not vary significantly with patch type, although the frequency of piercing relative to legitimate pollinator visits did increase in the large gaps. We attribute the latter result to aggregation of the hummingbird Eupherusa eximia, a chronic nectar robber, at dense clumps of long—flowered plant species that occurred in large gaps. Only one feature we examined suggested that patch type might directly affect the nature of species interactions: in two different analyses, the level of variation in frequency of hummingbird visits to flowers declined from large gaps to small gaps to forest. Results suggest that, unless the disturbance initiating a patch is unusually severe or widespread, interactions between the plants and hummingbirds examined are insensitive to patch type. Such species, existing in naturally dynamic forests throughout their recent evolutionary histories, presumably have become accommodated to frequent small—scale disturbance. Results also suggest that those habitat—related contrasts in plant reproductive traits and plant—pollinator interactions documented in other studies, which compare habitats initiated by anthropogenic disturbances with undisturbed patches, may be artifacts to some extent. Anthropogenically generated disturbance mosaics may promote the spread of species whose reproductive traits evolved under very different circumstances from mosaics generated by natural disturbances

Evaluation of Character Displacement Among Plants in Two Tropical Pollination Guilds

In cloud forest at Monteverde, Costa Rica, two guilds of bird—pollinated plants exist; on guild pollinated by long—billed hummingbirds, primarily the Green Hermit (Phaethornis guy), and one guild pollinated by short—billed hummingbirds, primarily the Purple—throated Mountain—gem (Lampornis calolaema). Plants were assigned to guilds based on hummingbird visit patterns documented during >4000 plant—hours of field observations, and on identities of pollen grains collected from 600 mist—netted hummingbirds. Other studies indicated that pollination in these plants is often insufficient for maximum seed set. Each guild was examined for character displacement expected within a stable assemblage of plants structured by competition for pollination. (1) By comparing observed flowering phenologies with those obtained through a randomization procedure, we determined whether each species' phenology minimized overlap with the remainder of its guild. (2) We also examined complementarity between phenological displacement and morphological displacement in reproductive structures. Neither guild exhibited pronounced character displacement. (1) In most cases, flowering phenologies were indistinguishable from those generated at random; the few statistically significant departures mostly indicated aggregation, rather than displacement, of flowering seasons. (2) In most cases, morphological similarity was independent of phenological similarity. The only statistically significant result among the studied species was a positive correlation, among long—flowered species only, between rarity and uniqueness of flowering season. We do not conclude that this absence of expected pattern indicates that competition never occurs or that competition is an inconsequential ecological event. Rather, we attribute absence of pattern to the following aspects of biological variability, two of which we have demonstrated in other studies. (1) Within any one year, density—dependent competition for pollination is sporadic, and is not clearly related to flowering season or morphological similarity. (2) The nature of interspecific interactions varies among years, as neither the relative intensities of flowering nor the flowering seasons themselves are consistent from year to year. (3) The nature of interspecific interactions varies with changes in species composition, which occur over short distances. (4) The assemblage of species is probably not stable over long time spans; the species have Gleasonian ecologies that change distribution and abundance faster than natural selection or diffuse competition can screen out improper phenotypes or species, respectively

Mixed Support for Spatial Heterogeneity in Species Interactions: Hummingbirds in a Tropical Disturbance Mosaic

Many natural landscapes experience frequent disturbance on a small scale. Disturbance loosens or disrupts relations between species, or between species and resources, characteristic of intact communities. One result is the release of previously scarce resources, leading to increased productivity and increased intensity of species interactions in disturbed patches as compared with undisturbed patches. Additionally, populations in disturbed sites may exploit resources in a more haphazard and opportunistic fashion than populations in undisturbed sites. The altered ecological conditions of disturbed sites may favor species different from those occupying undisturbed sites, leading to spatial heterogeneity in community composition. Nectar-feeding birds (mainly hummingbirds) inhabiting the natural disturbance mosaic of a Costa Rican cloud forest responded to habitat heterogeneity in complex ways. Whereas most ecological traits of hummingbird assemblages varied among patch types (understory of canopied forest; treefall gaps; large, landslide-like gaps), the direction of variation differed for different traits. Density of hummingbird food (nectar) was highest in treefall gaps, and some characteristics of hummingbirds (e.g., species diversity) reflected this enrichment. Variables that involve collective foraging by the entire hummingbird assemblage (e.g., intensity of interspecific competition) suggest that species interactions in the forest are the least haphazard, those in treefall gaps more haphazard, and those in large gaps the most haphazard. Even the largest gaps examined, however, were rarely invaded by hummingbird "weeds" available in the regional species pool, and interactions in these gaps showed only faint resemblance to those in the tremendously fluctuating competitive environments that characterize nectar-feeding bird assemblages in large anthropogenic old fields nearby or at other tropical sites. Our results, and reconsideration of results from other studies involving natural disturbance mosaics, suggest that responses of consumers to disturbance mosaics may often be subtle and complex. Comparisons between patch types in a natural disturbance mosaic need not resemble comparisons between points in a successional sequence after anthropogenic disturbance

Likelihood of Nursing Home Referral for Fecally Incontinent Elderly Patients is Influenced by Physician Views on Nursing Home Care and Outpatient Management of Fecal Incontinence

(1) Characterize physicians’ management practices for fecal incontinence (FI) among elderly patients, (2) describe physician perceptions of the quality of care for FI provided in nursing homes (NH), and (3) identify physician views and attributes associated with referral of elderly patients with FI to a NH

Survey of Geriatricians on the Effect of Fecal Incontinence on Nursing Home Referral: FECAL INCONTINENCE AND NURSING HOME REFERRAL

Determine the impact of fecal incontinence (FI) in health care providers’ decisions to refer patients for nursing home (NH) placement

Longitudinal evaluation of aflatoxin exposure in two cohorts in south-western Uganda

Aflatoxins (AF) are a group of mycotoxins. AF exposure causes acute and chronic adverse health effects such as aflatoxicosis and hepatocellular carcinoma in human populations, especially in the developing world. In this study, AF exposure was evaluated using archived serum samples from human immunodeficiency virus (HIV)-seronegative participants from two cohort studies in south-western Uganda. AFB1-lysine (AFB-Lys) adduct levels were determined via HPLC fluorescence in a total of 713 serum samples from the General Population Cohort (GPC), covering eight time periods between 1989 and 2010. Overall, 90% (642/713) of the samples were positive for AFB-Lys and the median level was 1.58 pg mg(-1) albumin (range = 0.40-168 pg mg(-1) albumin). AFB-Lys adduct levels were also measured in a total of 374 serum samples from the Rakai Community Cohort Study (RCCS), across four time periods between 1999 and 2003. The averaged detection rate was 92.5% (346/374) and the median level was 1.18 pg mg(-1) albumin (range = 0.40-122.5 pg mg(-1) albumin). In the GPC study there were no statistically significant differences between demographic parameters, such as age, sex and level of education, and levels of serum AFB-Lys adduct. In the RCCS study, longitudinal analysis using generalised estimating equations revealed significant differences between the adduct levels and residential areas (p = 0.05) and occupations (p = 0.02). This study indicates that AF exposure in people in two populations in south-western Uganda is persistent and has not significantly changed over time. Data from one study, but not the other, indicated that agriculture workers and rural area residents had more AF exposure than those non-agricultural workers and non-rural area residents. These results suggest the need for further study of AF-induced human adverse health effects, especially the predominant diseases in the region

Biomarker-defined clusters by level of Type 2 inflammatory involvement in severe asthma

Peer reviewedPostprin

Impact of pre-biologic impairment on meeting domain-specific biologic responder definitions in patients with severe asthma

The authors acknowledge Mr Aivaras Cepelis for his contribution during the development of the manuscript. The authors thank Ms Pui Yee Lai (M.A.), of the Observational and Pragmatic Research Institute (OPRI), and Ms Andrea Lim (BSc, Hons) of the Observational Pragmatic Research Institute (OPRI) for their editorial and formatting assistance that supported the development of this publication.Peer reviewe