bluuebunny/crossref_metadata_2025_split huggingface dataset:
Disrupting vagal feedback affects birdsong motor control
Authors: Méndez Jorge M. , Dall'Asén Analía G. , Goller Franz 
Published: November 2010

SUMMARY
Coordination of different motor systems for sound production involves the use of feedback mechanisms. Song production in oscines is a well-established animal model for studying learned vocal behavior. Whereas the online use of auditory feedback has been studied in the songbird model, very little is known about the role of other feedback mechanisms. Auditory feedback is required for the maintenance of stereotyped adult song. In addition, the use of somatosensory feedback to maintain pressure during song has been demonstrated with experimentally induced fluctuations in air sac pressure. Feedback information mediating this response is thought to be routed to the central nervous system via afferent fibers of the vagus nerve. Here, we tested the effects of unilateral vagotomy on the peripheral motor patterns of song production and the acoustic features. Unilateral vagotomy caused a variety of disruptions and alterations to the respiratory pattern of song, some of which affected the acoustic structure of vocalizations. These changes were most pronounced a few days after nerve resection and varied between individuals. In the most extreme cases, the motor gestures of respiration were so severely disrupted that individual song syllables or the song motif were atypically terminated. Acoustic changes also suggest altered use of the two sound generators and upper vocal tract filtering, indicating that the disruption of vagal feedback caused changes to the motor program of all motor systems involved in song production and modification. This evidence for the use of vagal feedback by the song system with disruption of song during the first days after nerve cut provides a contrast to the longer-term effects of auditory feedback disruption. It suggests a significant role for somatosensory feedback that differs from that of auditory feedback.
Mechanisms of temperature-dependent swimming: the importance of physics, physiology and body size in determining protist swimming speed
Authors: Beveridge Oliver S. , Petchey Owen L. , Humphries Stuart 
Published: November 2010

SUMMARYBody temperatures and thus physiological rates of poikilothermic organisms are determined by environmental temperature. The power an organism has available for swimming is largely dependent on physiological rates and thus body temperature. However, retarding forces such as drag are contingent on the temperature-dependent physical properties of water and on an organism's size. Consequently, the swimming ability of poikilotherms is highly temperature dependent. The importance of the temperature-dependent physical properties of water (e.g. viscosity) in determining swimming speed is poorly understood. Here we propose a semi-mechanistic model to describe how biological rates, size and the physics of the environment contribute to the temperature dependency of microbial swimming speed. Data on the swimming speed and size of a predatory protist and its protist prey were collected and used to test our model. Data were collected by manipulating both the temperature and the viscosity (independently of temperature) of the organism's environment. Protists were either cultured in their test environment (for several generations) or rapidly exposed to their test environment to assess their ability to adapt or acclimate to treatments. Both biological rates and the physics of the environment were predicted to and observed to contribute to the swimming speed of protists. Body size was not temperature dependent, and protists expressed some ability to acclimate to changes in either temperature or viscosity. Overall, using our parameter estimates and novel model, we are able to suggest that 30 to 40% (depending on species) of the response in swimming speed associated with a reduction in temperature from 20 to 5°C is due to viscosity. Because encounter rates between protist predators and their prey are determined by swimming speed, temperature- and viscosity-dependent swimming speeds are likely to result in temperature- and viscosity-dependent trophic interactions.
Sensorimotor gating in NTS1 and NTS2 null mice: effects ofd-amphetamine, dizocilpine, clozapine and NT69L
Authors: Oliveros Alfredo , Heckman Michael G. , del Pilar Corena-McLeod Maria , Williams Katrina , Boules Mona , Richelson Elliott 
Published: November 2010

SUMMARYPre-pulse inhibition (PPI) of the acoustic startle reflex is deficient in patients with schizophrenia. This deficiency is mimicked in mice by the use of the psychotomimetic drugs d-amphetamine and dizolcipine. Antipsychotic drugs such as clozapine are used to treat schizophrenic patients and are also administered to mice to prevent PPI disruption. Neurotensin (NT) produces antipsychotic-like effects when injected into rodent brain through its effects at NT subtype 1 (NTS1) and 2 (NTS2) receptors. We hypothesized that the NT receptor agonist (NT69L) would prevent PPI disruption in mice challenged with d-amphetamine (10 mg kg–1) and dizocilpine (1 mg kg–1). We investigated the role of NTS1 and NTS2 in PPI using wild-type (WT), NTS1 (NTS1–/–) and NTS2 (NTS2–/–) knockout mice, via its disruption by psychotomimetic drugs, as well as the ability of clozapine and NT69L to block these PPI disruptions. There were no differences in baseline PPI across the three genotypes. d-Amphetamine and dizocilpine disrupted PPI in WT and NTS2–/– mice but not in NTS1–/– mice. In WT mice, clozapine (1 mg kg–1) and NT69L (1 mg kg–1) significantly blocked d-amphetamine-induced disruption of PPI. Similarly, in WT mice, clozapine significantly blocked dizocilpine-induced PPI disruption, but NT69L did not. In NTS2–/– mice clozapine blocked d-amphetamine-but not dizocilpine-induced PPI disruption, while NT69L blocked both d-amphetamine- and dizocilpine-induced PPI disruption. Our results indicate that NTS1 seems essential for d-amphetamine and dizocilpine disruption of PPI. Additionally, this report provides support to the hypothesis that NT analogs could be used as novel antipsychotic drugs.
Coding and interaction of sex pheromone and plant volatile signals in the antennal lobe of the codling moth Cydia pomonella
Authors: Trona Federica , Anfora Gianfranco , Bengtsson Marie , Witzgall Peter , Ignell Rickard 
Published: November 2010

SUMMARY
In the codling moth Cydia pomonella (Lepidoptera: Tortricidae) plant volatiles attract males and females by upwind flight and synergise the male response to the female-produced sex pheromone, indicating a close relationship between the perception of social and environmental olfactory signals. We have studied the anatomical and functional organisation of the antennal lobe (AL), the primary olfactory centre, of C. pomonella with respect to the integration of sex pheromone and host-plant volatile information. A three-dimensional reconstruction of the glomerular structure of the AL revealed 50±2 and 49±2 glomeruli in males and females, respectively. These glomeruli are functional units involved in the coding of odour quality. The glomerular map of the AL was then integrated with electrophysiological recordings of the response of individual neurons in the AL of males and females to sex pheromone components and behaviourally active plant volatiles. By means of intracellular recordings and stainings, we physiologically characterised ca. 50 neurons in each sex, revealing complex patterns of activation and a wide variation in response dynamics to these test compounds. Stimulation with single chemicals and their two-component blends produced both synergistic and inhibitory interactions in projection neurons innervating ordinary glomeruli and the macroglomerular complex. Our results show that the sex pheromone and plant odours are processed in an across-fibre coding pattern. The lack of a clear segregation between the pheromone and general odour subsystems in the AL of the codling moth suggests a level of interaction that has not been reported from other insects.
Phenotypic plasticity and genetic adaptation to high-altitude hypoxia in vertebrates
Authors: Storz Jay F. , Scott Graham R. , Cheviron Zachary A. 
Published: November 2010

Summary
High-altitude environments provide ideal testing grounds for investigations of mechanism and process in physiological adaptation. In vertebrates, much of our understanding of the acclimatization response to high-altitude hypoxia derives from studies of animal species that are native to lowland environments. Such studies can indicate whether phenotypic plasticity will generally facilitate or impede adaptation to high altitude. Here, we review general mechanisms of physiological acclimatization and genetic adaptation to high-altitude hypoxia in birds and mammals. We evaluate whether the acclimatization response to environmental hypoxia can be regarded generally as a mechanism of adaptive phenotypic plasticity, or whether it might sometimes represent a misdirected response that acts as a hindrance to genetic adaptation. In cases in which the acclimatization response to hypoxia is maladaptive, selection will favor an attenuation of the induced phenotypic change. This can result in a form of cryptic adaptive evolution in which phenotypic similarity between high- and low-altitude populations is attributable to directional selection on genetically based trait variation that offsets environmentally induced changes. The blunted erythropoietic and pulmonary vasoconstriction responses to hypoxia in Tibetan humans and numerous high-altitude birds and mammals provide possible examples of this phenomenon. When lowland animals colonize high-altitude environments, adaptive phenotypic plasticity can mitigate the costs of selection, thereby enhancing prospects for population establishment and persistence. By contrast, maladaptive plasticity has the opposite effect. Thus, insights into the acclimatization response of lowland animals to high-altitude hypoxia can provide a basis for predicting how altitudinal range limits might shift in response to climate change.
Photoentrainment in blind and sighted rodent species: responses to photophase light with different wavelengths
Authors: Zubidat Abed E. , Nelson Randy J. , Haim Abraham 
Published: November 2010

SUMMARYOur study examined the impact of daylight (photophase) wavelength on the photoentrainment sensitivity of two species with vastly different visual systems. Social voles (Microtus socialis) and ‘blind’ mole rats (Spalax ehrenbergi) were exposed to short-wavelength (479 nm) or long-wavelength (697 nm) light at an intensity of 293 μW cm–2. Rhythms of urine production, urinary 6-sulfatoxymelatonin (6-SMT), urinary metabolites of adrenaline and cortisol, and oxygen consumption (VO2) were used as markers for the sensitivity of the photoentrainment system. Significant 24-h rhythms were detected in all variables for both species under short-wavelength light, whereas ultradian rhythms of 12- or 8-h were detected under long-wavelength light. Wavelength inversely affected 6-SMT levels in M. socialis (negative correlation) and S. ehrenbergi (positive correlation). Increased levels of stress hormone metabolites were detected in M. socialis under the long-wavelength light whereas, in S. ehrenbergi elevated levels were secreted under short-wavelength light. Long-wavelength light increased VO2 in M. socialis and decreased it in S. ehrenbergi; short-wavelength light elicited the opposite effects. Our results indicate that photophase wavelength is an integral light property for modulating photoperiodic responses in mammals, including visually challenged species. Finally, the spectral-induced differential responses between the two species potentially represent adaptive physiological flexibility in species with contrasting visual and habitat challenges.
Mechanics and kinematics of backward burrowing by the polychaete Cirriformia moorei
Authors: Che James , Dorgan Kelly M. 
Published: November 2010

SUMMARY
The polychaete Cirriformia moorei burrows in muddy sediments by fracture, using its hydrostatic skeleton to expand its anterior region and exert force against its burrow wall to extend a crack. Burrowing occurs in four phases: stretching forward into the burrow, extending the crack anteriorly, thickening the burrowing end to amplify stress at the tip of the crack, and bringing the rest of the body forward as a peristaltic wave travels posteriorly. Here, we show that C. moorei is also able to burrow with its posterior end using a similar mechanism of crack propagation and exhibiting the same four phases of burrowing. Worms burrowed backwards with similar speeds and stress intensity factors as forward burrowing, but were thinner and less blunt and did not slip as far away from the crack tip between cycles of burrowing. The anterior end is more muscular and rigid, and differences in body shapes are consistent with having reduce musculature to dilate the posterior segments while burrowing. Backward burrowing provides a unique opportunity to study the effects of morphology on burrowing mechanics within the same species under identical conditions.
The mechanics of gravitaxis inParamecium
Authors: Roberts A. M. 
Published: November 2010

SUMMARYAn analysis of swimming patterns in the ciliate Paramecium shows that the ability to swim preferentially upwards (negative gravitaxis) is primarily the result of upwardly curving trajectories. The trajectory characteristics are consistent with those produced by mechanical orientation. Cell profile measurements from microscope images suggest that the characteristic front–rear body asymmetry accounts for the observed orientation rates. Gravikinesis may result from interactions between the propelling cilia and the sedimentary flow around the cell, and it seems unlikely that an internal physiological gravity receptor exists in Paramecium.
Effects of insulin infusion on glucose homeostasis and glucose metabolism in rainbow trout fed a high-carbohydrate diet
Authors: Polakof S. , Moon T. W. , Aguirre P. , Skiba-Cassy S. , Panserat S. 
Published: November 2010

SUMMARY
The origin for the poor glucose utilization in carnivorous fish species fed high carbohydrate diets remains under debate. In the present study, we have fed rainbow trout a diet containing 30% carbohydrate for 1 or 5 days. In both cases, fish were implanted with mini-osmotic pumps releasing 0.7 i.u. kg–1 day–1 bovine insulin, and mRNA transcripts and the protein phosphorylation status of proteins controlling glycemia and glucose-related metabolism were studied in fish killed 6 h after the last meal. We demonstrate that when the exposure occurs over a short term (30 h), insulin exerts beneficial actions on trout glucose homeostasis, including a lowered glycemia and increased hepatic lipogenic and glycogenic potentials. However, when trout were fed for 5 days, these beneficial actions of insulin infusion were no longer observed. Thus, the increased lipogenic potential observed after one single meal was not present, and this together with the increased glycogenesis and the decreased glucose exported to the blood from the liver explains the lack of hypoglycemic action of insulin. The fact that insulin improved glucose homeostasis when administrated over a short time period implies that endogenous insulin secretion is inadequate in trout to deal with this amount of dietary carbohydrates. Moreover, the fact that a longer exposure to insulin resulted in a reduced response indicates that the rainbow trout is sensitive to insulin, re-enforcing the hypothesis that the hyperglycemia observed following a high carbohydrate meal is an insulin secretion issue rather an insulin action issue.
Knocking down expression of Hsp22 and Hsp23 by RNA interference affects recovery from chill coma in Drosophila melanogaster
Authors: Colinet Hervé , Lee Siu Fai , Hoffmann Ary 
Published: November 2010

SUMMARY
To protect cells from the damaging effects of environmental stresses, all organisms possess a universal stress response involving upregulation of heat shock proteins (Hsps). The mechanisms underlying chilling injuries and the subsequent recovery phase are only beginning to be understood in insects. Hsp22 and Hsp23 are both upregulated during the recovery from prolonged chill coma in Drosophila melanogaster. This prompted us to investigate the functional significance of these modulations by testing whether expression of these two small Hsps is necessary for recovery after cold stress. We used the GAL4/UAS system to separately knock down expression of Hsp22 and Hsp23, and assayed three aspects of recovery performance in transgenic adults that had undergone 12 h of chill coma at 0°C. The time to recover (short-term recovery) and mobility parameters (medium-term recovery) were significantly impaired in the transgenic flies in which Hsp22 or Hsp23 was suppressed. Our findings show that both Hsp22 and Hsp23 play important roles in the recovery from chill coma in adult males, and suggest that these contribute to adaptive responses to fluctuating thermal conditions.
Molecular evidence for color discrimination in the Atlantic sand fiddler crab, Uca pugilator
Authors: Rajkumar Premraj , Rollmann Stephanie M. , Cook Tiffany A. , Layne John E. 
Published: November 2010

SUMMARY
Fiddler crabs are intertidal brachyuran crabs that belong to the genus Uca. Approximately 97 different species have been identified, and several of these live sympatrically. Many have species-specific body color patterns that may act as signals for intra- and interspecific communication. To understand the behavioral and ecological role of this coloration we must know whether fiddler crabs have the physiological capacity to perceive color cues. Using a molecular approach, we identified the opsin-encoding genes and determined their expression patterns across the eye of the sand fiddler crab, Uca pugilator. We identified three different opsin-encoding genes (UpRh1, UpRh2 and UpRh3). UpRh1 and UpRh2 are highly related and have similarities in their amino acid sequences to other arthropod long- and medium-wavelength-sensitive opsins, whereas UpRh3 is similar to other arthropod UV-sensitive opsins. All three opsins are expressed in each ommatidium, in an opsin-specific pattern. UpRh3 is present only in the R8 photoreceptor cell, whereas UpRh1 and UpRh2 are present in the R1-7 cells, with UpRh1 expression restricted to five cells and UpRh2 expression present in three cells. Thus, one photoreceptor in every ommatidium expresses both UpRh1 and UpRh2, providing another example of sensory receptor coexpression. These results show that U. pugilator has the basic molecular machinery for color perception, perhaps even trichromatic vision.
The feasibility of catheter-directed thrombolysis for acute deep vein thrombosis: a regional perspective
Authors: Gauci B N , Powell J T , Hunt B J , Pilcher J , Morgan R , Thompson M M , Holt P J E 
Published: November 2010

Background Deep vein thromboses (DVTs) are a significant cause of morbidity and mortality. Valvular destruction leads to the spectrum of disease called the post-thrombotic syndrome (PTS) with the sequelae of chronic venous ulceration and a reduced quality of life. Catheter-directed thrombolysis (CDT) may reduce the incidence of PTS following an acute proximal DVT and increases quality of life thereafter, but it is uncertain what proportion of patients diagnosed with a DVT would be suitable for CDT. Methods This study quantified the proportion of patients investigated for DVT that would have been suitable for CDT. A retrospective review was performed of all upper and lower limb duplex ultrasound scans for suspected DVTs in a contemporary one-year period in a major regional vascular institute. All positive scans for acute proximal lower limb DVTs were compared against strict inclusion and exclusion criteria for CDT, based on national guidelines and international randomized trials. Results A total of 2368 duplex ultrasound venous investigations were performed in a one-year period and 252 scans demonstrated DVT. Of these, 158 were acute proximal lower limb DVTs. Application of the inclusion and exclusion criteria for CDT suggested that 47/158 (30%) were potentially suitable for CDT using current criteria. The median age of the 158 patients was 58 years, meaning that more than half were of working age and 54% were men. Conclusion Using current eligibility criteria, only about 30% of patients with DVT appear to be suitable for CDT.
Pagers and stethoscopes as vehicles of potential nosocomial pathogens in a tertiary care hospital in a developing country
Authors: Gopinath K G , Stanley Sulochana , Mathai Elizabeth , Chandy G M 
Published: November 2010

It has long been recognized that stethoscopes and other inanimate objects carry virulent micro-organisms that can cause nosocomial infections in susceptible patients. Among the frequently used items in hospitals are pagers and stethoscopes. The manner in which these items are used has the potential to cause colonization of bacteria and transfer of these bacteria to another person. This prospective study was performed in order to assess the colonization rates among randomly selected pagers and stethoscopes. We found that 15 (25%) pagers and 11 (27.5%) stethoscopes were contaminated. Enterococci (10%) were the most common isolates found followed by Staphylococci (8%) and Enterobacteriaceae (7%). There was no significant difference in the rates of colonization between shared and personal pagers ( P = 0.16). Stethoscopes were more likely to be contaminated with Enterococci compared to pagers ( P = 0.013, 95% confidence interval 1.3–52.9). Our findings confirm the need for protocols to prevent transmission of infection through inanimate objects.
Reconstructing and assessing the evaluation logic of the Dutch Closed Criminal Cases Evaluation Commission: report of a meta-evaluation
Authors: Klein Haarhuis C.M. , de Jongste W.M. 
Published: November 2010

In this paper, we offer an account of the meta-evaluation of a special administrative arrangement, the Dutch Closed Criminal Cases Evaluation Commission (Dutch acronym: CEAS). The CEAS is a provisional evaluation institution meant to investigate alleged missteps during criminal investigation and prosecution, which may have caused the conviction of an innocent person
We developed a tailor-made approach to reconstruct the commission's ‘evaluation logic’; this is illustrated by reconstructing the activities of a selection committee and two investigative subcommittees of the CEAS. Subsequently, we applied a set of criteria to assess among others the timeliness, independence and transparency of the commission's work. We offer a number of conclusions and recommendations, particularly with regard to future (meta-)evaluation research.