Field research on echolocation behavior in bats has emphasized studies of food acquisition, and the adaptive value of sonar signal design as been considered largely in the context of foraging. ...However, echolocation tasks related to spatial orientation also differ among bats and are relevant to understanding signal structure. Here, we argue that the evolution of echolocation in bats is characterized by two key innovations: first, the evolution of echolocation for spatial orientation and, second, a later transition for prey acquisition. This conceptual framework calls for a new view on field data from bats orienting and foraging in different types of habitats. According to the ecological constraints in which foraging bats operate, four distinct functional groups or guilds can be defined. Within each group, signal design and echolocation behavior are rather similar.
It is unclear how sustained increases in temperature and changes in precipitation, as a result of climate change, will affect crops and their interactions with agricultural weeds, insect pests and ...predators, due to the difficulties in quantifying changes in such complex relationships. We simulated the combined effects of increasing temperature (by an average of 1.4°C over a growing season) and applying additional rainwater (10% of the monthly mean added weekly, 40% total) using a replicated, randomized block experiment within a wheat crop. We examined how this affected the structure of 24 quantitative replicate plant–aphid–parasitoid networks constructed using DNA‐based methods. Simulated climate warming affected species richness, significantly altered consumer–resource asymmetries and reduced network complexity. Increased temperature induced an aphid outbreak, but the parasitism rates of aphids by parasitoid wasps remained unchanged. It also drove changes in the crop, altering in particular the phenology of the wheat as well as its quality (i.e., fewer, lighter seeds). We discuss the importance of considering the wider impacts of climate change on interacting species across trophic levels in agroecosystems.
Aims. We attempt to determine the dominant processes acting on star-forming disk galaxies as a result of the cluster environment by studying the normalised rates and radial distributions of star ...formation in galaxies within low-redshift clusters. Methods. We develop indicators of different processes based on the radial concentrations of R-band and Hα light within each of the galaxies studied. The tests are applied to galaxies in each of 3 environments – cluster, supercluster (outside the cluster virial radius) and field. We develop new diagnostic diagrams combining star-formation rate and spatial distribution information to differentiate between stripping of outer disk gas, general gas depletion, nuclear starbursts and galaxy-wide enhancement of star formation. Results. Hubble type classifications of cluster galaxies are found to correlate only weakly with their concentration indices, whereas this correlation is strong for non-cluster populations of disk galaxies. We identify a population of early-type disk galaxies in the cluster population with both enhanced and centrally-concentrated star formation compared to their field counterparts. The enhanced cluster galaxies frequently show evidence of disturbance. A small but non-negligible population of cluster galaxies with truncation of star formation in their outer disks is also found.
Echolocation signals were recorded from big brown bats, Eptesicus fuscus, flying in the field and the laboratory. In open field areas the interpulse intervals (IPI) of search signals were either ...around 134 ms or twice that value, 270 ms. At long IPI's the signals were of long duration (14 to 18-20 ms), narrow bandwidth, and low frequency, sweeping down to a minimum frequency (Fmin) of 22-25 kHz. At short IPI's the signals were shorter (6-13 ms), of higher frequency, and broader bandwidth. In wooded areas only short (6-11 ms) relatively broadband search signals were emitted at a higher rate (avg. IPI= 122 ms) with higher Fmin (27-30 kHz). In the laboratory the IPI was even shorter (88 ms), the duration was 3-5 ms, and the Fmin 30- 35 kHz, resembling approach phase signals of field recordings. Excluding terminal phase signals, all signals from all areas showed a negative correlation between signal duration and Fmin, i.e., the shorter the signal, the higher was Fmin. This correlation was reversed in the terminal phase of insect capture sequences, where Fmin decreased with decreasing signal duration. Overall, the signals recorded in the field were longer, with longer IPI's and greater variability in bandwidth than signals recorded in the laboratory.
The wing membrane of the big brown bat (Eptesicus fuscus) is covered by a sparse grid of microscopic hairs. We showed previously that various tactile receptors (e.g., lanceolate endings and Merkel ...cell neurite complexes) are associated with wing-hair follicles. Furthermore, we found that depilation of these hairs decreased the maneuverability of bats in flight. In the present study, we investigated whether somatosensory signals arising from the hairs carry information about airflow parameters. Neural responses to calibrated air puffs on the wing were recorded from primary somatosensory cortex of E. fuscus Single units showed sparse, phasic, and consistently timed spikes that were insensitive to air-puff duration and magnitude. The neurons discriminated airflow from different directions, and a majority responded with highest firing rates to reverse airflow from the trailing toward the leading edge of the dorsal wing. Reverse airflow, caused by vortices, occurs commonly in slowly flying bats. Hence, the present findings suggest that cortical neurons are specialized to monitor reverse airflow, indicating laminar airflow disruption (vorticity) that potentially destabilizes flight and leads to stall.
Bat wings are adaptive airfoils that enable demanding flight maneuvers. The bat wing is sparsely covered with sensory hairs, and wing-hair removal results in reduced flight maneuverability. Here, we report for the first time single-neuron responses recorded from primary somatosensory cortex to airflow stimulation that varied in amplitude, duration, and direction. The neurons show high sensitivity to the directionality of airflow and might act as stall detectors.
Objective
The authors investigated tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap) and influenza vaccination during pregnancy following Advisory Committee on Immunization ...Practices' (ACIP's) recommendation for antenatal pertussis vaccination.
Methods
A retrospective chart review was performed in 2019 of women receiving prenatal care at our institution between January 1, 2014 and December 31, 2018. Receipt of ACIP‐recommended vaccines were examined using Current Procedural Terminology codes to identify initiation of prenatal care, then administration of Tdap and influenza vaccines. Data were examined by individual practice (university faculty, community physicians, obstetrics and gynecology (OBGYN) residents, and family medicine residents, practice staff composition, vaccination protocol use, and insurance status. Statistical analyses were performed using χ2 testing and χ2 testing of linear trend.
Results
Within our cohort (n = 17 973), highest vaccination uptake occurred in the university‐based OBGYN faculty practice (Tdap = 58.2%, influenza = 56.5%) with lowest uptake in the OBGYN resident practice (Tdap = 28.6%, influenza = 18.5%). Higher uptake occurred in practices with standing orders, more advanced practice providers, lower provider to nursing ratios, and lower rates of Medicaid insurance.
Conclusion
These data demonstrated higher vaccination uptake with standing orders, more advanced practice providers, and lower provider to nurse ratios. Future work optimizing practice staff composition and vaccination protocols may increase vaccine uptake.
Synopsis
Vaccination uptake is most successful in practices with standing orders, lower rates of non‐Medicaid insurance, low provider to nurse ratios, and proportionally more advanced practice providers.
This paper describes measurements of the sonar beam pattern of flying echolocating bats, Eptesicus fuscus, performing various insect capture tasks in a large laboratory flight room. The beam pattern ...is deduced using the signal intensity across a linear array of microphones. The positions of the bat and insect prey are obtained by stereoscopic reconstruction from two camera views. Results are reported in the form of beam-pattern plots and estimated direction of the beam axis. The bat centers its beam axis on the selected target with a standard deviation (sigma) of 3 degrees. The experimental error is +/- 1.4 degrees. Trials conducted with two targets show that the bat consistently tracks one of the targets with its beam. These findings suggest that the axis of the bat sonar beam is a good index of selective tracking of targets, and in this respect is analogous to gaze in predominantly visual animals.
The bat wing is a highly adaptive airfoil that enables demanding flight maneuvers that are performed with robustness under turbulent conditions, and stability at slow flight speeds. The bat wing is ...covered with microscopically small, tactile hairs that have been shown to be involved in sensing air flow for improved flight maneuverability in 2 bat species, the frugivorous–nectarivorous Carollia perspicillata and the insectivorous Eptesicus fuscus. Here, we provide comparative data on the anatomy of these hairs and their distribution on the wing surface in 4 species of bats (C. perspicillata, Desmodus rotundus, E. fuscus, and Rousettus aegyptiacus), based on scanning electron microscopy analyses. Hairs were found on both the dorsal and ventral surfaces of the wing in all species, including the bony structures. They were generally sparsely distributed (1–3 hairs/mm2) and often found arranged in single file along elastin bands that extend through the wing membrane. Fringes of hairs also were found at the leading edge of the propatagium. The hairs were strongly tapered in all species. Their length varied from 0.08 mm (E. fuscus) to 3 mm (R. aegyptiacus). Hair length correlated positively with the body mass and wing loading value of each species, but not with aspect ratio, flight speed, or diet. We conclude that the hairs are spaced so that viscous coupling is negligible, at least for single-file hairs, and that they are scaled to the boundary layer of airflow limited to the first few millimeters close to the wing surface.
With the drastic decline of eastern oyster Crassostrea virginica populations in the Chesapeake Bay due to over-fishing, diseases and habitat destruction, there is interest in Maryland and Virginia in ...utilizing the non-native oyster species Crassostrea ariakensis for aquaculture, fishery resource enhancement, and ecological restoration. The International Council for the Exploration of the Sea (ICES) recommends that non-native species be examined for ecological, genetic and disease relationships in the native range prior to a deliberate introduction to a new region. Therefore, a pathogen survey of C. ariakensis and other sympatric oyster species was conducted on samples collected in the PR China, Japan and Korea using molecular diagnostics and histopathology. Molecular assays focused on 2 types of pathogens: protistan parasites in the genus Perkinsus and herpesviruses, both with known impacts on commercially important molluscan species around the world, including Asia. PCR amplification and DNA sequence data from the internal transcribed spacer region of the rRNA gene complex revealed the presence of 2 Perkinsus species not currently found in USA waters: P. olseni and an undescribed species. In addition, 3 genetic strains of molluscan herpesviruses were detected in oysters from several potential C. ariakensis broodstock acquisition sites in Asia. Viral gametocytic hypertrophy, Chlamydia-like organisms, a Steinhausia-like microsporidian, Perkinsus sp., Nematopsis sp., ciliates, and cestodes were also detected by histopathology.
Echolocating bats transmit ultrasonic vocalizations and use information contained in the reflected sounds to analyze the auditory scene. Auditory scene analysis, a phenomenon that applies broadly to ...all hearing vertebrates, involves the grouping and segregation of sounds to perceptually organize information about auditory objects. The perceptual organization of sound is influenced by the spectral and temporal characteristics of acoustic signals. In the case of the echolocating bat, its active control over the timing, duration, intensity, and bandwidth of sonar transmissions directly impacts its perception of the auditory objects that comprise the scene. Here, data are presented from perceptual experiments, laboratory insect capture studies, and field recordings of sonar behavior of different bat species, to illustrate principles of importance to auditory scene analysis by echolocation in bats. In the perceptual experiments, FM bats (Eptesicus fuscus) learned to discriminate between systematic and random delay sequences in echo playback sets. The results of these experiments demonstrate that the FM bat can assemble information about echo delay changes over time, a requirement for the analysis of a dynamic auditory scene. Laboratory insect capture experiments examined the vocal production patterns of flying E. fuscus taking tethered insects in a large room. In each trial, the bats consistently produced echolocation signal groups with a relatively stable repetition rate (within 5%). Similar temporal patterning of sonar vocalizations was also observed in the field recordings from E. fuscus, thus suggesting the importance of temporal control of vocal production for perceptually guided behavior. It is hypothesized that a stable sonar signal production rate facilitates the perceptual organization of echoes arriving from objects at different directions and distances as the bat flies through a dynamic auditory scene. Field recordings of E. fuscus, Noctilio albiventris, N. leporinus, Pippistrellus pippistrellus, and Cormura brevirostris revealed that spectral adjustments in sonar signals may also be important to permit tracking of echoes in a complex auditory scene.
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