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Triblehorn J D - - 2008
Through staged free-flight encounters between echolocating bats and praying mantids, we examined the effectiveness of two potential predator-evasion behaviors mediated by different sensory modalities: (1) power dive responses triggered by bat echolocation detected by the mantis ultrasound-sensitive auditory system, and (2) ;last-ditch' maneuvers triggered by bat-generated wind detected by the ...
Welch Kenneth C KC - - 2008
It is thought that the capacity of mammals to directly supply the energetic needs of exercising muscles using recently ingested fuels is limited. Humans, for example, can only fuel about 30%, at most, of exercise metabolism with dietary sugar. Using indirect calorimetry, i.e. measurement of rates of O(2) consumption and ...
Tamplin Jeanette - - 2008
This pilot study aimed to investigate the effects of vocal exercises and singing on intelligibility and speech naturalness for subjects with acquired dysarthria following traumatic brain injury or stroke. A multiple case study design was used, involving pre, mid, and post-treatment assessments of intelligibility, rate, naturalness, and pause time for ...
Hohlrieder Matthias - - 2008
The planning and execution of avalanche rescue missions to search for totally buried avalanche victims are mostly based on personal experience and preference, as evidence-based information from literature is almost completely missing. Hence, the aim of this study was to identify major factors determining the survival probability of totally buried ...
Kazi Rehan - - 2008
Twenty-seven total laryngectomy patients (19 males and 8 females) and 18 normal control subjects (10 males and 8 females) were subjected to electroglottography-based single voice recordings using sustained vowels and connected speech. The results showed poorer values and larger variability for all the voice measures for the total laryngectomy patients ...
Tanno Takayuki - - 2008
This study focused on variables that may account for response-rate differences under variable-ratio (VR) and variable-interval (VI) schedules of reinforcement. Four rats were exposed to VR, VI, tandem VI differential-reinforcement-of-high-rate, regulated-probability-interval, and negative-feedback schedules of reinforcement that provided the same rate of reinforcement. Response rates were higher under the VR ...
Kikukawa Azusa - - 2008
There are few in-flight studies of cognition-related cerebral oxygen status in helicopter pilots. Four male helicopter pilots volunteered for nine sorties during visual flight in a BK117 and UH-60J. The pilots' pre-frontal oxy-hemoglobin (O2Hb) and deoxy-hemoglobin (HHb) concentration were continuously monitored from the right/left sections of the forehead using near-infrared ...
Chivers Laura L - - 2008
Fifty-eight smokers received abstinence-contingent monetary payments for 1 (n=15) or 14 (n=3) days. Those who received contingent payments for 14 days also received 0, 1, or 8 experimenter-delivered cigarette puffs on 5 evenings. The relative reinforcing effects of smoking were assessed in a 3-hr session on the final study day, ...
Orlikoff Robert F - - 2008
Although effort closure techniques have a long history in the treatment of hypofunctional and psychogenic voice disorders, there have been surprisingly few studies of their specific laryngeal and phonatory effects. The present study was designed to provide preliminary data on physiologic changes in voice production associated with a weightlifting and ...
Butler Jolene A JA Research & Development, Edward Hines, Jr., VA Hospital, Hines, - - 2008
To test the reliability and validity of a physical activity instrument adapted for individuals with spinal cord injuries (SCI), the Physical Activity Instrument-SCI (PAI-SCI). Eligible participants completed the adapted PAI-SCI questionnaire at baseline and 1 week later. At baseline, they were also given an Actical accelerometer to wear on their ...
Baker Susan P SP Department of Health Policy and Management, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA. - - 2008
Many interventions have been implemented in recent decades to reduce pilot error in flight operations. This study aims to identify longitudinal trends in the prevalence and patterns of pilot error and other factors in U.S. air carrier mishaps. National Transportation Safety Board investigation reports were examined for 558 air carrier ...
Ruta Marcello - - 2007
As the most diverse group of early tetrapods, temnospondyls provide a unique opportunity to investigate cladogenetic patterns among basal limbed vertebrates. We present five species-level supertrees for temnospondyls, built using a variety of methods. The standard MRP majority rule consensus including minority components shows slightly greater resolution than other supertrees, ...
Kyonka Elizabeth G E - - 2008
Four pigeons responded in a concurrent-schedule procedure in which reinforcer rates and magnitudes changed unpredictably across sessions according to independent random series. Programmed relative reinforcement rates and magnitudes were always either 2:1 or 1:2. Pigeons' response allocation tended to stabilize within sessions and multiple regression analyses showed that it was ...
Watenpaugh Donald E - - 2007
Orthostatic intolerance follows actual weightlessness and weightlessness simulated by bed rest. Orthostasis immediately after acute exercise imposes greater cardiovascular stress than orthostasis without prior exercise. We hypothesized that 5 min/day of simulated orthostasis [supine lower body negative pressure (LBNP)] immediately following LBNP exercise maintains orthostatic tolerance during bed rest. Identical ...
Otsuka Yasutami - - 2007
This study investigated the flight responses induced by strenuous aerobatic demonstration flight and an air-to-air combat maneuvering flight in experienced pilots. Subjects were 54 military male pilots on a volunteer basis: 8 T-4 pilots (M= 35.8 yr., SD=4.9), 15 F-4 pilots (M=32.6 yr., SD=5.1), 13 F-15 pilots (M=33.8 yr., SD=1.0), ...
Hammond Sarah - - 2007
There are two modes of flight initiation in Drosophila melanogaster-escape and voluntary. Although the circuitry underlying escape is accounted for by the Giant fibre (GF) system, the system underlying voluntary flight initiation is unknown. The GF system is functionally complete before the adult fly ecloses, but immature adults initially fail ...
Pelletier David - - 2007
Although the adaptive value of flight may seem obvious, it is the most difficult behaviour of birds to monitor. Here, we describe a technique to quantify the frequency and the duration of flights over several months by implanting a data logger that records heart rate (fH), hydrostatic pressure (diving depth) ...
Lee Stuart M C - - 2007
INTRODUCTION: Exercise capacity is reduced after both short- and long-duration exposures to microgravity. Previously, we have documented that supine treadmill exercise within lower-body negative pressure (LBNP(ex)) maintains upright exercise responses in men after 5 and 15 d of bed rest, as a simulation of microgravity. PURPOSE: The purpose of this ...
Hamdan A-L - - 2008
(1) To examine the vocal symptoms and acoustic changes perceived in the short period immediately after laryngeal mask airway, and (2) to compare these findings in patients using laryngeal mask airway and endotracheal tube. A total of 27 patients were enrolled. They were evaluated pre-operatively and then at 2 and ...
Kelly Paul T - - 2007
Assessing the requirements for in-flight oxygen in passengers with pulmonary limitations can be a challenging task for clinicians. Aeromedical guidelines are available to help identify passengers that may require oxygen in flight. However, little is known about the actual in-flight response to passengers on oxygen. We measured the oxygen response ...
Edgar Julia - - 2008
Singers will often refrain from eating a meal before a performance because they believe it will interfere with breath support. As there are no objective data to support or refute this belief, the purpose of this study was to obtain pre- and postmeal data from professional and amateur singers to ...
Chung Daniel - - 2007
OBJECTIVES: The present study assessed the effects of a unique pitch-raising surgical technique designated upper displacement of the anterior commissure (UDAC), comparing the results with those obtained through cricothyroid approximation (CTA). METHODS: Vocal fold vibration was artificially evoked in 20 excised human larynges through tracheal injection of compressed air. Vocal ...
Jarvis Steve - - 2007
INTRODUCTION: Accidents caused by spinning from low turns continue to kill glider pilots despite the introduction of specific exercises aimed at increasing pilot awareness and recognition of this issue. METHOD: In-cockpit video cameras were used to analyze flying accuracy and log the areas of visual interest of 36 qualified glider ...
Tsai Chen-Gia - - 2008
The objective of this study was to investigate the underlying laryngeal mechanisms during the specific human 4-kHz vocalization. The laryngeal configuration during this vocalization was measured using high-resolution computerized tomographic scan and videostrobolaryngoscopy. The color Doppler imaging (CDI) of medical ultrasound was used to detect the vibrations of glottal and ...
Martin P R - - 2007
The increase in diversity towards the equator arises from latitudinal variation in rates of cladogenesis, extinction, immigration and/or emigration of taxa. We tested the relative contribution of all four processes to the latitudinal gradient in 26 marine invertebrate orders with extensive fossil records, examined previously by David Jablonski. Coupling Jablonski's ...
Netto Kevin J - - 2007
INTRODUCTION: Performing specific neck strengthening exercises has been proposed to decrease the incidence of neck injury and pain in high performance combat pilots. However, there is little known about these exercises in comparison to the demands on the neck musculature in flight. METHODS: Eight male non-pilots performed specific neck exercises ...
Baevsky Roman M - - 2007
Impaired autonomic control represents a cardiovascular risk factor during long-term spaceflight. Little has been reported on blood pressure (BP), heart rate (HR), and heart rate variability (HRV) during and after prolonged spaceflight. We tested the hypothesis that cardiovascular control remains stable during prolonged spaceflight. Electrocardiography, photoplethysmography, and respiratory frequency (RF) ...
Schneider Stefan - - 2007
Numerous studies have shown significant effects of weightlessness on adaptational processes of the CNS, cardiovascular and/or muscular system. Most of these studies have been carried out during parabolic flights, using the recurring 20 s of weightlessness at each parabola. Although some of these studies reported on potential influences not only ...
Savel'ev S A - - 2007
Studies on Sprague-Dawley rats using in vivo microdialysis and HPLC showed that the acquisition and performance of a classical conditioned reflex with pain reinforcement was accompanied by increases in the concentrations of citrulline (a side product of nitric oxide formation) and arginine (the substrate of NO synthase) in the intercellular ...
Maguire David R DR University of North Carolina, Wilmington, NC, USA. - - 2007
Four pigeons were trained on concurrent variable-interval 30-s schedules. Relative reinforcer amounts arranged across the two alternatives were varied across sessions according to a pseudorandom binary sequence [cf., Hunter, I., Davison, M., 1985. Determination of a behavioral transfer function: white-noise analysis of session-to-session response-ratio dynamics on concurrent VI schedules. J. ...
Finlayson Clive - - 2007
The latter part of the last glaciation, 50,000-12,000 years ago (kya), was characterized by a rapidly changing climate, cold conditions and corresponding vegetation and faunal turnover. It also coincided with the extinction of the Neanderthals and the expansion of modern human populations. Established views of modern human superiority over Neanderthals ...
Bruzek Jennifer L - - 2007
The relative reinforcing value of toys was assessed in the absence of, and immediately following, participant observation of a peer manipulating one of the toys. Preference assessments were used to identify preference hierarchies. Reinforcer assessments were conducted with a high-preference item, a low-preference item, and a control. Each participant allocated ...
Wallach Helene S HS Tsfat College, Tsfat, Israel. - - 2007
Flight phobia is a common and debilitating specific phobia. Recently, an effective technology, called Virtual Reality (VR), has been developed for the treatment of various anxiety disorders including flight phobia. This article reports the results of a pilot study consisting of four subjects treated for Flight Phobia using Virtual Reality. ...
Di Rienzo M M Centro di Bioingegneria, Fondazione Don, Carlo Gnocchi, ONLUS, 20133 Milano, Italy. - - 2007
On the basis of indirect evidences it has been hypothesized that during space missions the almost complete absence of gravity might impair the baroreflex control of circulation. In the first part of this paper we report results obtained from a series of experiments carried out to directly verify this hypothesis ...
Schmidt-Wellenburg Carola A - - 2007
Many bird species steeply increase their body mass prior to migration. These fuel stores are necessary for long flights and to overcome ecological barriers. The elevated body mass is generally thought to cause higher flight costs. The relationship between mass and costs has been investigated mostly by interspecific comparison and ...
Lin Emily - - 2008
This study was aimed at identifying acoustic and physiological measures useful for monitoring voice changes in postnasopharyngeal patients with nonlaryngeal malignancies, and providing evidences of vocal tract effect on voice through comparisons between individuals with and without intact vocal tract. Simultaneous acoustic-electroglottographic signals recorded during phonation of vowels /i/ and ...
Karbhari Vistasp M - - 2007
OBJECTIVES: The aim of the study was to compare the mechanical characteristics of two ultrahigh molecular weight polyethylene (UHMWPE) fiber-based triaxial braided reinforcements having different denier braider yarns used in fiber reinforced dental composites to elucidate differences in response and damage under flexural loading. METHODS: Two commercially available triaxial braided ...
Kelly Paul T - - 2006
INTRODUCTION: There is little data available to determine the normal response to normobaric hypoxia inhalation testing (NHIT) and air travel. Quantifying a healthy response may assist in the evaluation of passengers considered at risk for air travel. The aims of this study were: (1) to quantify the degree of desaturation ...
Wade-Galuska Tammy - - 2007
Three rhesus monkeys' lever presses produced aspartame-sweetened water according to a fixed-ratio schedule. The response requirement was increased across sessions and a demand-function analysis was used to assess the reinforcing effectiveness of different magnitudes of aspartame by manipulating reinforcer duration (1 and 3s) in Phase 1 and concentration (0.3, 0.5, ...
Carroll Thomas T University of Colorado at Denver and Health Sciences Center, Department of Otolaryngology, Denver, Colorado 80262-0001, USA. - - 2006
To collect objective vibration dose data on singers and relate them to subjective measurements of vocal fatigue. Seven subjects completed a 2-week study period. The National Center for Voice and Speech (NCVS) dosimeter recorded vocal load, soft phonation tasks, and subjective soft voice ratings. Three vocal doses (time, distance, and ...
Oliveira Giselle A - - 2006
Lipophorin (Lp), either labeled in diacylglycerol moiety with [(3)H]-Palmitic acid or in phospholipid moiety with (32)Pi, was injected into Rhodnius prolixus females. Insects were induced to flight for different times. In just a few minutes of flight, the transfer of radioactivity to ovaries decreased, accompanied by its increase to flight ...
Phillmore Leslie S - - 2006
Black-capped chickadees have a rich vocal repertoire including learned calls and the learned fee-bee song. However, the neural regions underlying these vocalizations, such as HVC, area X, and RA (robust nucleus of arcopallium), remain understudied. Here, we document seasonal changes in fee-bee song production and show a marked peak in ...
Comyns Thomas M - - 2006
Complex training research has indicated that 3-4 minutes may be an optimum intracomplex rest interval. The purpose of this study was to determine if a heavy resistive exercise causes performance enhancement of a slow stretch-shortening cycle exercise and if there is an optimal rest interval. Eighteen subjects performed countermovement jumps ...
Lychakov D V - - 2006
Mathematical modeling suggests that relatively large values of otolith mass asymmetry in fishes can alter acoustic functionality and may be responsible for abnormal fish behavior when subjected to weightlessness during parabolic or space flight [D.V. Lychakov, Y.T. Rebane, Otolith mass asymmetry in 18 species of fish and pigeon, J. Grav. ...
Sanabria Federico - - 2006
Twelve pigeons were exposed to negative automaintenance contingencies for 17-27 sessions immediately after brief (14-16 sessions) or extended (168-237 sessions) exposure to positive automaintenance contingencies, or after 4-10 sessions of instrumental training. In all conditions, negative automaintenance contingencies virtually eliminated responding, reducing response rates to an average 1.3 responses per ...
Niemi Matti - - 2006
PURPOSE: The effects of orthognathic surgery on the phonetic quality of speech were studied by analyzing the main acoustic features of vowel sounds. PATIENTS AND METHODS: Five men with dentofacial deformities undergoing surgical operation for correction of malocclusion were enrolled in the study. The speech material consisted of 8 vowels ...
Heymann Nicole - - 2006
During elevated locomotor activity such as flight, Drosophila satisfies its increased respiratory demands by increasing the total spiracle opening area of the tracheal gas exchange system. It has been assumed that in a diffusion-based system, each spiracle contributes to oxygen flux into and carbon dioxide flux out of the tracheal ...
Iellamo Ferdinando - - 2006
One of the most important features of prolonged weightlessness is a progressive impairment of muscular function with a consequent decrease in exercise capacity. We tested the hypothesis that the impairment in musculo-skeletal function that occurs in microgravity results in a potentiation of the muscle metaboreflex mechanism and also affects baroreflex ...
Schreiber Sebastian J - - 2006
A discrete-time host-parasitoid model including host-density dependence and a generalized Thompson escape function is analyzed. This model assumes that parasitoids are egg-limited but not search-limited, and is proven to exhibit five types of dynamics: host failure in which the host goes extinct in the parasitoid's presence or absence, unconditional parasitoid ...
Vertigan Anne E - - 2006
OBJECTIVE/HYPOTHESIS: The purpose of this study was to examine respiratory function in a group of patients with muscle tension dysphonia (MTD) DESIGN: Cross-sectional analytical study. METHODS: Participants included 15 people with a diagnosis of MTD referred to speech pathology for management of their voice disorder, fiberoptic evidence of glottal or ...
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