bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chewing rates among domestic dog breeds
Authors: Gerstner Geoffrey E. , Cooper Meghan , Helvie Peter 
Published: June 2010

SUMMARYThe mammalian masticatory rhythm is produced by a brainstem timing network. The rhythm is relatively fixed within individual animals but scales allometrically with body mass (Mb) across species. It has been hypothesized that sensory feedback and feed-forward adjust the rhythm to match the jaw's natural resonance frequency, with allometric scaling being an observable consequence. However, studies performed with adult animals show that the rhythm is not affected by jaw mass manipulations, indicating that either developmental or evolutionary mechanisms are required for allometry to become manifest. The present study was performed to tease out the relative effects of development versus natural selection on chewing rate allometry. Thirty-one dog breeds and 31 mass-matched non-domestic mammalian species with a range in Mb from ∼2 kg to 50 kg were studied. Results demonstrated that the chewing rhythm did not scale with Mb among dog breeds (R=0.299, P&gt;0.10) or with jaw length (Lj) (R=0.328, P&gt;0.05). However, there was a significant relationship between the chewing rhythm and Mb among the non-domestic mammals (R=0.634, P&lt;0.001). These results indicate that scaling is not necessary in the adult animal. We conclude that the central timing network and related sensorimotor systems may be necessary for rhythm generation but they do not explain the 1/3rd to 1/4th allometric scaling observed among adult mammals. The rhythm of the timing network is either adjusted to the physical parameters of the jaw system during early development only, is genetically determined independently of the jaw system or is uniquely hard-wired among dogs and laboratory rodents.
Cardiovascular performance of six species of field-acclimatized centrarchid sunfish during the parental care period
Authors: Cooke Steven J. , Schreer Jason F. , Wahl David H. , Philipp David P. 
Published: June 2010

SUMMARYParental care is an energetically costly period of the life history of many fish species characterized by extended high intensity activity. To date, there have been no studies that have investigated the cardiovascular correlates of extended parental care in fish. Using Doppler flow probes, the cardiovascular performance of six syntopic centrarchid fish species (N=232) that provide sole, male parental care was examined across a range of water temperatures that encompass their reproductive periods (14–26°C). Experiments were restricted to males but included both nesting and non-nesting individuals to evaluate the cardiovascular performance of fish during parental care. Resting values for cardiac output () and heart rate (fH) tended to be higher for nesting fish when adjusted for variation in temperature. Both of these cardiac variables also increased with water temperature. Stroke volume (VS) was similar among nesting and non-nesting fish and was generally thermally insensitive. When exposed to exhaustive exercise, nesting fish took longer to exhaust than non-nesting individuals. The high resting levels found in nesting fish accompanied by only minor increases in maximal values typically resulted in reductions in cardiac scope. Cardiovascular variables recovered more quickly in nesting fish, which could facilitate the high activity and bursting associated with parental care. Interspecifically, several cardiovascular variables were correlated with parental care activity. Parental care investment became more energetically expensive as the degree of cardiac frequency modulation decreased. Additionally, as the duration of parental care increased, so did the time required for fish to become exhausted, although this relationship was probably influenced by the fact that the larger species (e.g. smallmouth bass Micropterus dolomieu; largemouth bass Micropterus salmoides) provided the lengthiest care. Collectively, these data indicate that fish that provide parental care possess adaptations, including sufficient phenotypic plasticity, such that they can enhance their ability to provide high intensity protracted care, and emphasize the nexus between behavior and physiology.
Collision avoidance by running insects: antennal guidance in cockroaches
Authors: Baba Yoshichika , Tsukada Akira , Comer Christopher M. 
Published: June 2010

SUMMARY
Cockroaches were observed with videographic methods as escape running was initiated, but with obstacles in the path of their run. The goal was to determine the repertoire of possible responses to obstacles and the sensory cues used to trigger the responses. Intact cockroaches collided with obstacles on only about 10% of trials. The most common collision avoidance strategy was simply to stop running prior to impact. However, occasionally animals moved vertically and climbed over the barrier, or turned and navigated an edge of the obstacle, or completely reversed run direction. The avoidance strategies chosen depended on the size and configuration of the obstacle. Tests for the use of vision in detecting obstacles showed that its role, if any, is small. However, all manipulations that altered the antennal system changed behavior in a way consistent with the hypothesis that antennal mechanosensation plays a major role in collision avoidance. For example, reducing antennal length, or severing the main antennal nerve without altering the length produced significant increases in the frequency of collisions. Tests with tethered insects showed that (1) the antennae are preferentially directed forward as animals run, and (2) nearly simultaneous contact with both antennae is required to make the cockroach stop. Our data indicate that running cockroaches employ strategies that set their sensorimotor systems in a mode of readiness to deal with obstacles and they suggest that sensory information about the presence and configuration of obstacles is used to make choices, at very short latencies, about how to respond to obstructions.
The fish eye view: are cichlids conspicuous?
Authors: Dalton Brian E. , Cronin Thomas W. , Marshall N. Justin , Carleton Karen L. 
Published: June 2010

SUMMARY
The extent of animal colouration is determined by an interplay between natural and sexual selection. Both forces probably shape colouration in the speciose, rock-dwelling cichlids of Lake Malawi. Sexual selection is thought to drive male colouration, overcoming natural selection to create conspicuous colour patterns via female mate choice and male–male competition. However, natural selection should make female cichlids cryptic because they mouthbrood their young. We hypothesize that as a result of both sexual and natural selection, males will have colours that are more conspicuous than female colours. Cichlid spectral sensitivity, especially in the ultraviolet, probably influences how colours appear to them. Here we use simple models of the trichromatic colour space of cichlid visual systems to compare the conspicuousness of male and female nuptial colours of nine species. Conspicuousness of colours was evaluated as their Euclidian distance in colour space from environmental backgrounds and from other colours on the same fish. We find in six of the nine species that breeding males have colours that are statistically more conspicuous than female colours. These colours contrast strongly with each other or with the backgrounds, and they fall within a range of spectra best transmitted in the habitat. Female colour distances were sometimes smaller, suggesting that females of some species are more cryptic than males. Therefore, selection can differentially act to generate male colours that are more conspicuous than those in females. However, in two species, females had colours that were more conspicuous than male colours, suggesting that other selective forces and possibly sexual conflicts are acting in this system.
Inhibition of glutamine synthetase during ammonia exposure in rainbow trout indicates a high reserve capacity to prevent brain ammonia toxicity
Authors: Sanderson L. A. , Wright P. A. , Robinson J. W. , Ballantyne J. S. , Bernier N. J. 
Published: June 2010

SUMMARY
Glutamine synthetase (GSase), the enzyme that catalyses the conversion of glutamate and ammonia to glutamine, is present at high levels in vertebrate brain tissue and is thought to protect the brain from elevated ammonia concentrations. We tested the hypothesis that high brain GSase activity is critical in preventing accumulation of brain ammonia and glutamate during ammonia loading in the ammonia-intolerant rainbow trout. Trout pre-injected with saline or the GSase inhibitor methionine sulfoximine (MSOX, 6 mg kg–1), were exposed to 0, 670 or 1000 μmol l–1 NH4Cl in the water for 24 and 96 h. Brain ammonia levels were 3- to 6-fold higher in ammonia-exposed fish relative to control fish and MSOX treatment did not alter this. Brain GSase activity was unaffected by ammonia exposure, while MSOX inhibited GSase activity by ∼75%. Brain glutamate levels were lower and glutamine levels were higher in fish exposed to ammonia relative to controls. While MSOX treatment had little impact on brain glutamate, glutamine levels were significantly reduced by 96 h. With ammonia treatment, significant changes in the concentration of multiple other brain amino acids occurred and these changes were mostly reversed or eliminated with MSOX. Overall the changes in amino acid levels suggest that multiple enzymatic pathways can supply glutamate for the production of glutamine via GSase during ammonia exposure and that alternative transaminase pathways can be recruited for ammonia detoxification. Plasma cortisol levels increased 7- to 15-fold at 24 h in response to ammonia and MSOX did not exacerbate this stress response. These findings indicate that rainbow trout possess a relatively large reserve capacity for ammonia detoxification and for preventing glutamate accumulation during hyperammonaemic conditions.
Evidence for glutamate, GABA and NO in coordinating behaviour in the sponge, Ephydatia muelleri (Demospongiae, Spongillidae)
Authors: Elliott Glen R. D. , Leys Sally P. 
Published: June 2010

SUMMARY
The view that sponges lack tissue level organisation, epithelia, sensory cells and coordinated behaviour is challenged by recent molecular studies showing the existence in Porifera of molecules and proteins that define cell signalling systems in higher order metazoans. Demonstration that freshwater sponges can contract their canals in an organised manner in response to both external and endogenous stimuli prompted us to examine the physiology of the contraction behaviour. Using a combination of digital time-lapse microscopy, high-performance liquid chromatography–mass spectrometry (HPLC–MS) analysis, immunocytochemistry and pharmacological manipulations, we tested the role of the diffusible amino acids glutamate and γ-aminobutyric acid (GABA) and a short-lived diffusible gas, nitric oxide (NO), in triggering or modulating contractions in Ephydatia muelleri. We identified pools of glutamate, glutamine and GABA used to maintain a metabotropic glutamate and GABA receptor signalling system. Glutamate induced contractions and propagation of a stereotypical behaviour inflating and deflating the canal system, acting in a dose-dependent manner. Glutamate-triggered contractions were blocked by the metabatropic glutamate receptor inhibitor AP3 and by incubation of the sponge in an allosteric competitive inhibitor of glutamate, Kynurenic acid. Incubation in GABA inhibited glutamate-triggered contractions of the sponge. Nitric oxide synthase, involved in the formation of the diffusible gas NO, was localised using NADPH-diaphorase to mesenchyme cells in the osculum and pinacoderm. A cGMP assay showed the same cells were labelled suggesting that the NO system is functional. Our findings suggest sponges coordinate behaviour using chemical messenger systems common to other animals.
Snout allometry in seahorses: insights on optimisation of pivot feeding performance during ontogeny
Authors: Roos Gert , Van Wassenbergh Sam , Herrel Anthony , Adriaens Dominique , Aerts Peter 
Published: June 2010

SUMMARYAs juvenile life-history stages are subjected to strong selection, these stages often show levels of performance approaching those of adults, or show a disproportionately rapid increase of performance with age. Although testing performance capacity in aquatic suction feeders is often problematic, in pivot feeders such as seahorses models have been proposed to estimate whether snout length is optimal to minimise the time needed to reach the prey. Here, we investigate whether the same model can also explain the snout lengths in an ontogenetic series of seahorses, explore how pivot feeding kinematics change during ontogeny, and test whether juveniles show disproportionate levels of performance. Our analysis shows that the dimensions of the snout change during ontogeny from short and broad to long and narrow. Model calculations show that the snout lengths of newborn and juvenile seahorses are nearly optimal for minimising prey reach time. However, in juveniles the centre of head rotation in the earth-bound frame of reference is located near the posterior end of the head, whereas in adults it is shifted forward and is located approximately above the eye. Modelling shows that this forward shift in the centre of rotation has the advantage of decreasing the moment of inertia and the torque required to rotate the head, but has the disadvantage of slightly increasing the time needed to reach the prey. Thus, the snout lengths of juvenile seahorses appear to be close to optimal, suggesting that they reach levels of performance close to adult levels, which illustrates the pervasive nature of selection on performance in juveniles.
Oxidative stress and information content of black and yellow plumage coloration: an experiment with greenfinches
Authors: Hõrak Peeter , Sild Elin , Soomets Ursel , Sepp Tuul , Kilk Kalle 
Published: June 2010

SUMMARYCarotenoid and melanin pigments in the plumage of birds are hypothesized to be sensitive to oxidative stress. We manipulated oxidative status of captive greenfinches (Carduelis chloris L.) by the administration of buthionine sulfoximine (BSO), a selective inhibitor of the synthesis of glutathione (GSH), an intracellular antioxidant. Half of the birds in the treated group, as well as in the control group, also received dietary carotenoid (lutein) supplementation. BSO treatment reduced erythrocyte GSH levels and caused oxidative damage as indicated by the increased concentration of plasma malondialdehyde (MDA), an end product of lipid peroxidation. BSO treatment also reduced the brightness (i.e. increased blackness) of the tips of tail feathers grown during the experiment. These results show that a low systemic GSH level is required for development of eumelanin plumage coloration and that such a low GSH level is also potentially dangerous for the organism. Carotenoid supplementation increased plasma carotenoid levels and chroma of the yellow parts of the feathers grown during the experiment. However, carotenoid supplementation did not reduce plasma MDA levels. Manipulation of GSH did not affect plasma carotenoids or carotenoid-based plumage coloration. These findings argue against the antioxidant function of lutein in vivo and carotenoid signaling of antioxidant status.
Asymmetry of different brain structures in homing pigeons with and without navigational experience
Authors: Mehlhorn Julia , Haastert Burkhard , Rehkämper Gerd 
Published: June 2010

SUMMARY
Homing pigeons (Columba livia f.d.) are well-known for their homing abilities, and their brains seem to be functionally adapted to homing as exemplified, e.g. by their larger hippocampi and olfactory bulbs. Their hippocampus size is influenced by navigational experience, and, as in other birds, functional specialisation of the left and right hemispheres (‘lateralisation’) occurs in homing pigeons. To show in what way lateralisation is reflected in brain structure volume, and whether some lateralisation or asymmetry in homing pigeons is caused by experience, we compared brains of homing pigeons with and without navigational experience referring to this. Fourteen homing pigeons were raised under identical constraints. After fledging, seven of them were allowed to fly around the loft and participated successfully in races. The other seven stayed permanently in the loft and thus did not share the navigational experiences of the first group. After reaching sexual maturity, all individuals were killed and morphometric analyses were carried out to measure the volumes of five basic brain parts and eight telencephalic brain parts. Measurements of telencephalic brain parts and optic tectum were done separately for the left and right hemispheres. The comparison of left/right quotients of both groups reveal that pigeons with navigational experience show a smaller left mesopallium in comparison with the right mesopallium and pigeons without navigational experience a larger left mesopallium in comparison with the right one. Additionally, there are significant differences between left and right brain subdivisions within the two pigeon groups, namely a larger left hyperpallium apicale in both pigeon groups and a larger right nidopallium, left hippocampus and right optic tectum in pigeons with navigational experience. Pigeons without navigational experience did not show more significant differences between their left and right brain subdivisions. The results of our study confirm that the brain of homing pigeons is an example for mosaic evolution and indicates that lateralisation is correlated with individual life history (experience) and not exclusively based on heritable traits.
Preparation of Aluminum Hydroxide and Alumina Particles in an Ionic Liquid
Authors: Kinoshita Keigo , Minami Hideto , Tarutani Yasunori , Okubo Masayoshi 
Published: June 2010

Abstract
Highly crystalline Al(OH)3 particles were successfully prepared by the sol–gel process of aluminum isopropoxide (Al(OPri)3) in a hydrophilic ionic liquid (IL), 1-butyl-3-methylimidazolium tetrafluoroborate ([Bmim][BF4]) at 30 °C using NH4OH as catalyst. Moreover, crystalline alumina particles were prepared from the Al(OH)3 particles by heat treatment at 300 °C. When 2-propanol was used as medium for comparison, obtained particles were low crystalline AlO(OH). This difference seemed to arise from the difference in the local structure of Al(OPri)3 in IL.
Room-temperature Synthesis of CdMoO4 Nanooctahedra in the Hemline Length of 30 nm
Authors: Li Yanfen , Mi Yan , Jiang Junying , Huang Zaiyin 
Published: June 2010

Abstract
Uniform single-crystal CdMoO4 nanooctahedra in the hemline regime of 30 nm have been synthesized via a reverse-microemulsion route at room temperature. The as-prepared products were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and selected area electron diffraction (SAED). Room-temperature photoluminescence (PL) measurement exhibited a blue emission peaking at 438 nm under the 360 nm excitation, which is mainly attributed to the existence of intrinsic distortions into the [MoO4] tetrahedron moiety in the lattices.
Computer-Aided Learning and Assessment for Spreadsheet Modelling of Critical Path Analysis
Authors: Baker Barrie M. 
Published: June 2010

In many universities, courses in quantitative methods for business are provided for students from a variety of disciplines. Student numbers on these courses can be very large and, for such non-specialist courses, there can be a wide range of student ability. The purpose of this study was to develop computer-aided learning and assessment programs which overcome the difficulties of teaching a very large group of mixed ability students and provide a fast, error-free and consistent method of marking. It is intended to provide a more satisfactory experience for students, who can vary their practice time to suit their own individual needs, and also to save a lot of time for lecturers in setting and marking assignments. The specific aim of this study was to develop a modelling task for such a group that would be less mechanistic than the network analysis tasks previously reported. Thus, students are required to construct a complete spreadsheet model for a critical path network, starting from a table of predecessors. The model has to be constructed with formulae so as to enable experimentation and sensitivity analysis in traditional operations research style. A program has been developed which generates an apparently endless sequence of different tables of predecessors, then checks for mistakes in the students' formulae as well as identifying poor presentation such as unnecessary crossing or right-to-left pointing arrows. Two forms of the program are available. The first provides feedback to the students so that they can learn how to construct the model. The second provides no feedback, but prints some coded information to assist lecturers with marking. There is also a spreadsheet tutorial for the students to help them get started. The program has been used with great success by a group of 351 students, who reported that the approach was not only more effective than traditional pencil-and-paper approaches to learning, but was fun to use as well.
Operating Room Manager Game
Authors: Hans Erwin W. , Nieberg Tim 
Published: June 2010

The operating room (OR) department of a hospital forms the heart of the organization, where the single largest cost is incurred. This document presents and reports on the “Operating Room Manager Game,” developed to give insight into managing a large hospital's OR department at various levels of control, and the difficulties of applying OR/MS techniques in healthcare. The players take on the role of management teams of the OR department, and in subsequent rounds follow the actual planning and scheduling process-starting with strategic choices on capacities for an upcoming year, and ending with daily, online planning of actual surgeries in each operating room. The game ends with each team also benchmarking and evaluating the strategies of all players. The game is motivated by the actual setting of a large academic hospital in the Netherlands, which also provided real-life data. It is currently used as part of the lecture on “Optimization of Healthcare Processes” in the Industrial Engineering & Management master's program at the University of Twente. It integrates students' foreknowledge regarding various OR/MS subjects, applied in a healthcare setting.
The substrate specificity profile of human granzyme A
Authors: Van Damme Petra , Maurer-Stroh Sebastian , Hao Han , Colaert Niklaas , Timmerman Evy , Eisenhaber Frank , Vandekerckhove Joël , Gevaert Kris 
Published: June 2010

Abstract
The exact biological function of granzyme A, a granule-associated serine protease belonging to the tryptase family of proteases, is still a matter of debate because conflicting roles have been suggested, such as initiation of caspase-independent apoptosis-like cell death and endogenous modulation of inflammatory processes. In contrast to its well-studied family member, granzyme B, far less is known about the physiological targets of granzyme A. Using an N-terminal peptide-centric proteomics technology, the substrate specificity of human granzyme A was extensively characterized at the level of macromolecular protein substrates. Overall, more than 260 cleavage sites, almost exclusively favoring basic residues at the P1 position, in approximately 200 unique protein substrates, including the well-known in vitro substrates APEX-endonuclease 1 and different histones, were identified. Further substrate characterization was used to delineate physical properties in the substrate specificity profiles, which further highlights important aspects in protease/substrate biology.