bluuebunny/crossref_metadata_2025_split huggingface dataset:
Antennule morphology and flicking kinematics facilitate odor sampling by the spiny lobster, Panulirus argus
Authors: Reidenbach Matthew A. , George Nicole , Koehl M. A. R. 
Published: August 2008

SUMMARY
Many arthropod olfactory appendages bear arrays of hair-like chemosensory sensillae. Odor molecules in the fluid around the animal must reach the surfaces of those hairs to be sensed. We used the lateral flagellum of the olfactory antennule of the spiny lobster, Panulirus argus, as a system to study how the morphology, orientation, and motion of sensilla-bearing appendages affects the small-scale water flow within the hair array. We tested whether antennule flicking enables lobsters to take discrete odor samples by measuring flow fields through an aesthetasc array on a dynamically scaled physical model of a P. argus antennule. Particle image velocimetry revealed that the magnitude and duration of velocity through the aesthetasc array during the rapid flick downstroke is just enough to allow complete replacement of the fluid entrained within the hair array. The complex zig-zag arrangement of aesthetascs hairs, combined with their offset orientation along the antennule, generates flow velocities that are uniform along the length of the hairs. This increases fluid exchange during the flick and reduces the boundary layer thickness surrounding the hairs. The return stroke occurs at about a quarter the speed of the flick, but the velocity of the fluid between the aesthetascs is approximately 25 times slower. The retained fluid during the return stroke remains virtually unstirred and sufficient time occurs for odor molecules to diffuse to aesthetasc surfaces.
Metabolic and molecular stress responses of sublittoral bearded horse musselModiolus barbatusto warming sea water: implications for vertical zonation
Authors: Anestis Andreas , Pörtner Hans O. , Lazou Antigone , Michaelidis Basile 
Published: August 2008

SUMMARYThe present study set out to investigate the thermal limits of the Mediterranean bivalve Modiolus barbatus, acclimated to various temperatures, and includes a comparison of laboratory determined limits with its temperature-dependent restriction to deeper water layers in its natural habitat. Thermal responses and limits were determined by integrating information from various levels of biological organization, including the expression of Hsp70 and Hsp90, the phosphorylation of stress-activated protein kinases, p38 mitogen-activated protein kinase (p38 MAPK) and cJun-N-terminal kinases (JNKs) as well as metabolic adjustments. The latter were assessed by examining temperature effects on the activity of the key glycolytic enzyme pyruvate kinase (PK). The expression of Hsp70 and Hsp90 was activated when mussels were acclimated to temperatures above 20°C. Increased phosphorylation of p38 MAPK and JNKs at about the same temperatures indicate activation of MAPK signaling cascades and their potential involvement in the induction of Hsp genes. As indicated by the activity of PK, Modiolus barbatus maintains some aerobic capacity when acclimated to temperatures up to 24°C, while further warming probably caused metabolic depression and a shift from aerobic to anaerobic metabolism. An increase in mortality occurred in parallel, during acclimation to temperatures above 24°C. Our results indicate that both the biochemical stress indicators and metabolic status respond in parallel once hypoxemia becomes extreme. Comparison with our previous study of thermal limits and vertical distribution in M. galloprovincialis dwelling in shallow waters emphasizes the relevance of maintained aerobic scope over that of passive tolerance for permanent vertical zonation at higher temperatures in the field. These findings and conclusions are in line with the concept of oxygen and capacity limited thermal tolerance and the associated systemic to molecular hierarchy of thermal limitation.
Reversed functional topology in the antennal lobe of the male European corn borer
Authors: Kárpáti Zsolt , Dekker Teun , Hansson Bill S. 
Published: August 2008

SUMMARY
The European corn borer Ostrinia nubilalis (Hübner) is a model of evolution of sexual communication in insects. Two pheromone strains produce and respond to opposite ratios of the two pheromone components, Z11 and E11-tetradecenylacetate. The Z-strain uses a ratio of 97:3 of Z11:E11 tetradecenylacetate, whereas the E-strain uses a ratio of 1:99. We studied how the difference in male preference correlates with differences in wiring of olfactory input and output neurons in the antennal lobe (AL). Activity-dependent anterograde staining, intracellular recording and immunocytochemistry were used to establish the structure and function of male olfactory receptor neurons (ORNs) and AL projection neurons (PNs). Physiologically characterized neurons were reconstructed using confocal microscopy of α-synapsin stained ALs. The ALs of males and females in both strains had approximately 64 glomeruli. In males the macroglomerular complex (MGC) was morphologically similar in the two strains and consisted of two major compartments, a large, medial compartment folded around a smaller,lateral one. Extensive physiological and morphological analysis revealed that in both strains the major pheromone component-specific ORNs and PNs arborize in the medial MGC glomerulus, whereas those sensitive to the minor pheromone component arborize in the lateral glomerulus. In other words, the two strains have an indistinguishable MGC morphology, but a reversed topology. Apparently,the single-gene-mediated shift that causes a radical change in behavior is located upstream of the antennal lobes, i.e. at the ORN level.
Hydrozoan nematocytes send and receive synaptic signals induced by mechano-chemical stimuli
Authors: Oliver Dominik , Brinkmann Martin , Sieger Thiemo , Thurm Ulrich 
Published: August 2008

SUMMARYNematocytes, the stinging cells of Hydrozoa, can be considered as prototypic mechanosensory hair cells bearing a concentric hair bundle, the cnidocil apparatus. These cells produce typical mechanoreceptor potentials in response to deflection of their cnidocil. Here we show that mechanosensory signals are relayed to neighbouring nematocytes via chemical neurotransmission and that nematocytes receive synaptic input from surrounding nematocytes, hair cells and probably from epithelial cells. Intracellular voltage recordings from stenotele nematocytes of capitate hydroid polyps showed two distinct types of responses when other nematocytes within the same tentacle were mechanically stimulated: (i) graded depolarizations of variable duration (`L-potentials'), and (ii) uniform impulse-like, often repetitive depolarizations (`T-potentials') that occurred in correlation with contractions of epitheliomuscular cells. Voltage clamp experiments showed that despite the stereotyped time course of T-potentials, their generation did not involve electrically excitable conductances. Instead, time course,post-stimulus delay, susceptibility to blockers of neurotransmission and gap junctions, and induction by electrical stimulation of other nematocytes indicate that L- and T-potentials are postsynaptic, most likely glutamatergic potentials. Both result from different presynaptic pathways: L-potentials are induced monosynaptically by presynaptic receptor potentials, T-potentials are most likely triggered by presynaptic action potentials propagating through the ectodermal epithelium via gap junctions. Moreover,contact-chemosensory (phospholipid) stimulation of the presynaptic nematocyte is a positive modulator of the nematocyte's afferent synaptic efficacy and of cnidocyst discharge, both triggered by mechanoreceptor potentials. The results reveal that hydrozoan nematocytes act as bimodal sensory cells, signalling coincident chemical and mechanical stimuli indicative of prey, and receive signals from other nematocytes and sensory cells.
Multifocal optical systems and pupil dynamics in birds
Authors: Lind Olle E. , Kelber Almut , Kröger Ronald H. H. 
Published: August 2008

SUMMARYIn animal eyes of the camera type longitudinal chromatic aberration causes defocus that is particularly severe in species with short depth of focus. In a variety of vertebrates, multifocal optical systems compensate for longitudinal chromatic aberration by concentric zones of different refractive powers. Since a constricting circular pupil blocks peripheral zones, eyes with multifocal optical systems often have slit pupils that allow light to pass through all zones, irrespective of the state of pupil constriction. Birds have circular pupils and were therefore assumed to have monofocal optical systems. We examined the eyes of 45 species (12 orders) of bird using videorefractometry,and the results are surprising: 29 species (10 orders) have multifocal systems, and only five species (five orders) have monofocal systems. The results from 11 species (four orders) are inconclusive. We propose that pupils`switching' between being fully opened (multifocal principle) to maximally closed (pinhole principle) can make multifocal optical systems useful for animals with circular pupils. Previous results indicate that mice have both multifocal optical systems and switching pupils. Our results suggest that parrots may use a similar mechanism. By contrast, owl pupils responded weakly to changes in illumination and stayed remarkably wide even in full daylight. Moreover, the parrots opened their pupils at higher light levels than owls,which correlates with the differences in sensitivity between diurnal and nocturnal eyes.
Methyl farnesoate couples environmental changes to testicular development in the crabCarcinus maenas
Authors: Nagaraju G. P. C. , Borst D. W. 
Published: August 2008

SUMMARYCarcinus maenas males have two major color phases. Green-phase males molt frequently and tend to live in brackish estuaries during the summer. After becoming red-phase males, they molt infrequently, have higher mating success, and live in cooler, deeper water. We found profound differences between these two phases in the way salinity and temperature affect hemolymph levels of methyl farnesoate (MF), a hormone that affects crustacean reproduction. Few green-phase males (&lt;10%) had detectable MF in 33 ppt seawater (SW) at 11 or 18°C. By contrast, about 30% of the red-phase males had detectable MF at either temperature. After transfer to 5 ppt SW, none of the green-phase males had detectable MF at 11°C whereas 100% of green-phase males did at 18°C. By contrast, 100% of the red-phase males had detectable MF in 5 ppt SW at either temperature. At 11°C,green-phase males had detectable MF after eyestalk ablation (ESA), showing that they can produce MF. There was no additional increase in MF levels when ESA animals of either color phase were transferred to 5 ppt SW, suggesting that the eyestalk is the primary regulator of the MF response to low salinity. MF levels of green-phase males were increased by injecting MF, by ESA, or by exposure to 5 ppt SW at 18°C. The testicular index of these treated animals nearly doubled after two weeks. Our results strongly suggest that environmental conditions such as temperature and salinity, affect testicular development in this crab by changing its MF levels.
Allometry of evaporative water loss in marsupials: implications of the effect of ambient relative humidity on the physiology of brushtail possums(Trichosurus vulpecula)
Authors: Cooper C. E. , Withers P. C. 
Published: August 2008

SUMMARYTo better understand the effects of ambient relative humidity (RH) on physiological variables and the implications of RH-correcting evaporative water loss (EWL) data for marsupials, we examined the effect of RH on EWL,body temperature (Tb), metabolic rate (MR) and thermal conductance (C) of the brushtail possum (Trichosurus vulpecula), a medium-sized marsupial. Correcting EWL data for 27 species of marsupial for water vapour pressure deficit (ΔWVP) in the chamber during measurement significantly increased, rather than decreased, the variability of the allometric relationship for EWL. For the brushtail possum,both ambient temperature (Ta) and RH significantly affected EWL. At Ta=25°C, EWL was independent of RH at≤63% RH, but decreased linearly at higher RH values. At Ta=30°C, EWL was significantly related to RH from 26%to 92% RH. There was a significant effect of Ta on Tb and dry thermal conductance (Cdry;higher at 30°C), but no effect of RH. For MR and wet thermal conductance(Cwet) there was a significant effect of Ta (MR higher and Cwet lower at 25°C), and RH at Ta=30°C (MR higher and Cwet lower at the lowest RH) but not at 25°C. Our results indicate that brushtail possums do not necessarily show the linear relationship between ambient RH and EWL expected for an endotherm, possibly because of behavioural modification of their immediate microclimate. This may account for the failure of WVP deficit correction to improve the allometric EWL relationship for marsupials. Chamber RH is an important environmental factor to be considered when measuring standard physiological variables such as MR and Cwet.
Cues for acoustic detection of prey: insect rustling sounds and the influence of walking substrate
Authors: Goerlitz Holger R. , Greif Stefan , Siemers Björn M. 
Published: August 2008

SUMMARY
When insects walk, they generally produce sounds. These can reveal the walkers' presence and location to potential predators such as owls, bats and nocturnal primates. Additionally, predators might extract information on taxon, palatability, size or profitability from the rustling sounds. In contrast to ear morphology, hearing physiology and psychoacoustics of acoustically oriented predators, little attention has hitherto been paid to the acoustic structure and information content of prey sounds. An important element in the ecology of acoustic prey detection remained virtually unexplored: the influence of the substrate type on rustling sounds. In this study, we analysed amplitude and frequency parameters from insects walking on various natural substrates, in both Germany (Carabus beetles) and Madagascar (various beetles and cockroaches). The data show that rustling sound amplitude and frequency content depend on substrate type. On moist substrates arthropods produced less intense and less broadband rustling sounds than on dry substrates. Sound pressure level was reduced by about 6 dB,halving the detection range for the predator. For a given insect, rustling sound amplitude increased with walking speed. Finally, we found that the previously established correlation of arthropod size and rustling amplitude holds across multiple substrates. Based on these data, we provide for the first time estimates of realistic detection distances in the field. These distances range from below 1 m to over 13 m, depending on the substrate,insect mass, walking speed and background noise level. These estimates are crucial for an understanding of the foraging ecology, foraging efficiency and sensory ecology of acoustic predators.
Exploration and navigation in the blind mole rat (Spalax ehrenbergi): global calibration as a primer of spatial representation
Authors: Avni Reut , Tzvaigrach Yael , Eilam David 
Published: August 2008

SUMMARYThe aim of this study was to uncover the process of initial spatial mapping of the environment. For this, blind mole rats (Spalax ehrenbergi),were tested in an unfamiliar square arena, in order to reveal how they construct a spatial representation. The mole rats first displayed a build-up phase, in which they gradually formed a path along the perimeter while travelling slowly, frequently pausing and repeating previously travelled segments of the path. This behaviour was followed by a free-travel phase, in which the mole rats appeared to locomote smoothly along the perimeter and through the centre of the arena while travelling faster with fewer stops or repetitions of path segments. Familiarity with the environment was reflected in local shortcuts at the arena corners and global shortcuts (crosscuts)through the arena centre. We suggest that scanning the perimeter throughout the build-up phase constitute a process of calibration, i.e. forming an initial representation of the size and perhaps the shape of the environment– a sort of basic global map. We further suggest that this calibration is later used for navigation, as indicated by the emergence of global crosscuts in the subsequent phase. Further investigation of the build-up phase, e.g. by manipulating environment size, might provide additional insight into the course of establishment of global environment representation(mapping).
The effects of gravity on human walking: a new test of the dynamic similarity hypothesis using a predictive model
Authors: Raichlen David A. 
Published: August 2008

SUMMARYThe dynamic similarity hypothesis (DSH) suggests that differences in animal locomotor biomechanics are due mostly to differences in size. According to the DSH, when the ratios of inertial to gravitational forces are equal between two animals that differ in size [e.g. at equal Froude numbers, where Froude =velocity2/(gravity × hip height)], their movements can be made similar by multiplying all time durations by one constant, all forces by a second constant and all linear distances by a third constant. The DSH has been generally supported by numerous comparative studies showing that as inertial forces differ (i.e. differences in the centripetal force acting on the animal due to variation in hip heights), animals walk with dynamic similarity. However, humans walking in simulated reduced gravity do not walk with dynamically similar kinematics. The simulated gravity experiments did not completely account for the effects of gravity on all body segments, and the importance of gravity in the DSH requires further examination. This study uses a kinematic model to predict the effects of gravity on human locomotion,taking into account both the effects of gravitational forces on the upper body and on the limbs. Results show that dynamic similarity is maintained in altered gravitational environments. Thus, the DSH does account for differences in the inertial forces governing locomotion (e.g. differences in hip height)as well as differences in the gravitational forces governing locomotion.
Serum Total Prolactin and Monomeric Prolactin Reference Intervals Determined by Precipitation with Polyethylene Glycol: Evaluation and Validation on Common ImmunoAssay Platforms
Authors: Beltran Luisa , Fahie-Wilson Michael N , McKenna T Joseph , Kavanagh Lucille , Smith Thomas P 
Published: August 2008

Abstract
Background: Macroprolactin is an important source of immunoassay interference that commonly leads to misdiagnosis and mismanagement of hyperprolactinemic patients. We used the predominant immunoassay platforms for prolactin to assay serum samples treated with polyethylene glycol (PEG) and establish and validate reference intervals for total and monomeric prolactin.
Methods: We used the Architect (Abbott), ADVIA Centaur and Immulite (Siemens Diagnostics), Access (Beckman Coulter), Elecsys (Roche Diagnostics), and AIA (Tosoh) analyzers with samples from healthy males (n = 53) and females (n = 93) to derive parametric reference intervals for total and post-PEG monomeric prolactin. Concentrations of immunoreactive prolactin isoforms in serum samples from healthy individuals were established by gel filtration chromatography (GFC). We then used samples from 22 individuals whose hyperprolactinemia was entirely attributable to macroprolactin and 32 patients with true hyperprolactinemia to compare patient classifications and prolactin concentrations measured by GFC with the newly derived post-PEG reference intervals.
Results: Parametric reference intervals for post-PEG prolactin in male and female serum samples, respectively, were (in mIU/L): 61–196, 66–278 (Centaur); 63–245, 75–381 (Elecsys); 70–301, 92–469 (Access); 72–229, 79–347 (Architect); 73–247, 83–383 (AIA); and 78–263, 85–394 (Immulite). Concordance between GFC and immunoassay-specific post-PEG reference intervals was observed in 311 of 324 cases and for 31 of 32 patients with true hyperprolactinemia and 17 of 22 patients with macroprolactinemia. Results leading to misclassification occurred in a few analyzers for 5 macroprolactinemia patient samples with relatively minor increases in post-PEG prolactin (mean 61 mIU/L).
Conclusions: Our validated normative reference data for sera pretreated with PEG and analyzed on the most commonly used immunoassay platforms should facilitate the more widespread introduction of macroprolactin screening by clinical laboratories.
Die moderne Staatsbürgerschaft und ihre Grenzen: Anmerkungen zu T. H. Marshalls „citizenship”-Konzept (Modern Citizenship and its Limits: Notes on T. H. Marshall's Concept of Citizenship)
Authors: Fahrmeir Andreas 
Published: August 2008

Zusammenfassung
In einer kritischen Auseinandersetzung mit T. H. Marshalls klassischer Vorlesung „Citizenship and Social Class” argumentiert der Beitrag, daß die Formen und Grenzen des Verbands der Staatsbürger, die für Marshall 1949 keine Rolle spielten, einer detaillierteren Betrachtung wert sind. Eine empirisch genaue Bestimmung der Gruppen, welche von Staatsbürgerschaftsrechten profitierten, und eine Erforschung der Institutionen, welche über Inklusion und Exklusion entschieden, verspricht neue Erkenntnisse über die Bedeutung des Zentral- oder Nationalstaates im Vergleich mit der lokalen Verwaltung ebenso wie eine Präzision des auch durch die Marshall-Rezeption aufgeweichten, für die Forschungsdebatte aber zentralen Begriffs citizenship.
A Molecular Selection Index Method Based on Eigenanalysis
Authors: Cerón-Rojas J Jesús , Castillo-González Fernando , Sahagún-Castellanos Jaime , Santacruz-Varela Amalio , Benítez-Riquelme Ignacio , Crossa José 
Published: August 2008

Abstract
The traditional molecular selection index (MSI) employed in marker-assisted selection maximizes the selection response by combining information on molecular markers linked to quantitative trait loci (QTL) and phenotypic values of the traits of the individuals of interest. This study proposes an MSI based on an eigenanalysis method (molecular eigen selection index method, MESIM), where the first eigenvector is used as a selection index criterion, and its elements determine the proportion of the trait's contribution to the selection index. This article develops the theoretical framework of MESIM. Simulation results show that the genotypic means and the expected selection response from MESIM for each trait are equal to or greater than those from the traditional MSI. When several traits are simultaneously selected, MESIM performs well for traits with relatively low heritability. The main advantages of MESIM over the traditional molecular selection index are that its statistical sampling properties are known and that it does not require economic weights and thus can be used in practical applications when all or some of the traits need to be improved simultaneously.