bluuebunny/crossref_metadata_2025_split huggingface dataset:
A behavioral perspective on the biophysics of the light-dependent magnetic compass: a link between directional and spatial perception?
Authors: Phillips John B. , Muheim Rachel , Jorge Paulo E. 
Published: September 2010

Summary
In terrestrial organisms, sensitivity to the Earth's magnetic field is mediated by at least two different magnetoreception mechanisms, one involving biogenic ferromagnetic crystals (magnetite/maghemite) and the second involving a photo-induced biochemical reaction that forms long-lasting, spin-coordinated, radical pair intermediates. In some vertebrate groups (amphibians and birds), both mechanisms are present; a light-dependent mechanism provides a directional sense or ‘compass’, and a non-light-dependent mechanism underlies a geographical-position sense or ‘map’. Evidence that both magnetite- and radical pair-based mechanisms are present in the same organisms raises a number of interesting questions. Why has natural selection produced magnetic sensors utilizing two distinct biophysical mechanisms? And, in particular, why has natural selection produced a compass mechanism based on a light-dependent radical pair mechanism (RPM) when a magnetite-based receptor is well suited to perform this function? Answers to these questions depend, to a large degree, on how the properties of the RPM, viewed from a neuroethological rather than a biophysical perspective, differ from those of a magnetite-based magnetic compass. The RPM is expected to produce a light-dependent, 3-D pattern of response that is axially symmetrical and, in some groups of animals, may be perceived as a pattern of light intensity and/or color superimposed on the visual surroundings. We suggest that the light-dependent magnetic compass may serve not only as a source of directional information but also provide a spherical coordinate system that helps to interface metrics of distance, direction and spatial position.
Hydrodynamic pumping by serial gill arrays in the mayfly nymphCentroptilum triangulifer
Authors: Sensenig Andrew T. , Kiger Ken T. , Shultz Jeffrey W. 
Published: September 2010

SUMMARYAquatic nymphs of the mayfly Centroptilum triangulifer produce ventilatory flow using a serial array of seven abdominal gill pairs that operates across a Reynolds numbers (Re) range from 2 to 22 during ontogeny. Net flow in small animals is directed ventrally and essentially parallel to the stroke plane (i.e. rowing), but net flow in large animals is directed dorsally and essentially transverse to the stroke plane (i.e. flapping). Detailed flow measurements based on Particle Image Velocimetry (PIV) ensemble-correlation analysis revealed that the phasing of the gills produces a time-dependent array of vortices associated with a net ventilatory current, a fluid kinematic pattern, here termed a ‘phased vortex pump’. Absolute size of vortices does not change with increasing animal size or Re, and thus the vortex radius (Rv) decreases relative to inter-gill distance (Lis) during mayfly growth. Given that effective flapping in appendage-array animals requires organized flow between adjacent appendages, we hypothesize that rowing should be favored when Lis/Rv&lt;1 and flapping should be favored when Lis/Rv&gt;1. Significantly, the rowing-to-flapping transition in Centroptilum occurs at Re∼5, when the mean dynamic inter-gill distance equals the vortex radius. This result suggests that the Re-based rowing–flapping demarcation observed in appendage-array aquatic organisms may be determined by the relative size of the propulsive mechanism and its self-generated vortices.
Paralytic activity of lysophosphatidylcholine from saliva of the waterbugBelostoma anurum
Authors: Silva-Cardoso Lívia , Caccin Paola , Magnabosco Anna , Patrón Maria , Targino Mariane , Fuly André , Oliveira Giselle A. , Pereira Marcos H. , do Carmo Maria das Graças T. , Souza Amanda S. , Silva-Neto Mário A. C. , Montecucco Cesare , Atella Georgia C. 
Published: September 2010

SUMMARYLysophosphatidylcholine (LPC) is a major bioactive lipid that is enzymatically generated by phospholipase A2 (PLA2). Previously, we showed that LPC is present in the saliva of the blood-sucking hemipteran Rhodnius prolixus and modulates cell-signaling pathways involved in vascular biology, which aids blood feeding. Here, we show that the saliva of the predator insect Belostoma anurum contains a large number of lipids with LPC accounting for 25% of the total phospholipids. A PLA2 enzyme likely to be involved in LPC generation was characterized. The activity of this enzyme is 5-fold higher in Belostoma saliva than in other studied hemipterans, suggesting a close association with the predator feeding habits of this insect. Belostoma employs extra-oral digestion, which allows for ingestion of larger prey than itself, including small vertebrates such as amphibians and fish. Therefore, prey immobilization during digestion is essential, and we show here that Belostoma saliva and B. anurum saliva purified LPC have paralytic activity in zebrafish. This is the first evidence that lysophospholipids might play an important role in prey immobilization, in addition to contributing to blood feeding, and might have been an evolutionary acquisition that occurred long before the appearance of hematophagy in this animal group.
Behaviour towards an unpreferred colour: can green flowers attract foraging hawkmoths?
Authors: Balkenius Anna , Balkenius Christian 
Published: September 2010

SUMMARY
Naïve hawkmoths (Manduca sexta) learn from a single trial to approach and attempt to feed from an artificial flower of an innately unpreferred green colour even when a distractor flower with a preferred yellow colour is present. In some of the animals, the choice of the innately unpreferred colour during free-flight testing persists for several days despite not being rewarded and eventually leads to starvation. The results show that moths exhibit a very strong flower constancy that is not limited to the colours of nectar flowers.
Source levels of echolocation signals vary in correlation with wingbeat cycle in landing big brown bats (Eptesicus fuscus)
Authors: Koblitz Jens C. , Stilz Peter , Schnitzler Hans-Ulrich 
Published: September 2010

SUMMARYRecordings of the echolocation signals of landing big brown bats with a two-dimensional 16-microphone array revealed that the source level reduction of 7 dB per halving of distance is superimposed by a variation of up to 12 dB within single call groups emitted during the approach. This variation correlates with the wingbeat cycle. The timing of call emission correlates with call group size. First pulses of groups containing many calls are emitted earlier than first calls in groups with fewer calls or single calls. This suggests that the emission of pulse groups follows a fixed motor pattern where the information gained from the preceding pulse group determines how many calls will be emitted in the next group. Single calls and call groups are centred at the middle of the upstroke. Expiration is indicated by call emission. The pause between groups is centred at the middle of the downstroke and indicates inspiration. The hypothesis that the source level variation could be caused by changes in the subglottic pressure due to the contraction of the major flight muscles is discussed.
Behavioral and neurophysiological responses of an insect to changing ratios of constituents in host plant-derived volatile mixtures
Authors: Najar-Rodriguez A. J. , Galizia C. G. , Stierle J. , Dorn S. 
Published: September 2010

SUMMARY
Ratios of compounds in host plant odors fluctuate with the phenological stage of the plant. In the present study, we investigated the effect of changing ratios of host plant volatile constituents on herbivore insect attraction and olfactory information processing. We tested a synthetic mixture of bioactive peach shoot volatiles with different concentrations of one of the mixture constituents, benzonitrile, on oriental fruit moth Cydia (=Grapholita) molesta females. Y-tube olfactometer bioassays showed that female attraction to the mixture was maintained while increasing the benzonitrile level up to 100 times. Further increases led to behaviorally ineffective mixtures. Then, we recorded odor-evoked neural activity patterns in the antennal lobes, the main olfactory center of the brain, using calcium imaging. Benzonitrile-containing mixtures elicited strong activation in two glomeruli, which were found to process mixture-related information in specific ways. Activation in one glomerulus directly paralleled behavioral effects of the different ratios tested whereas a deviating pattern was noted in the other glomerulus. Our results indicate that the ratio of constituents in a volatile mixture can be varied to a certain degree without reducing female attraction. Thus, volatile blends in nature might vary quantitatively within a certain range without affecting odor-guided host location. Neurophysiological results showed that the processing of mixture-related information inside the antennal lobes is not uniform across glomeruli. Thus, final processing of this information probably takes place in higher-order brain centers.
Control of tumbling during the locust jump
Authors: Cofer David , Cymbalyuk Gennady , Heitler William J. , Edwards Donald H. 
Published: September 2010

SUMMARYLocust can jump precisely to a target, yet they can also tumble during the trajectory. We propose two mechanisms that would allow the locust to control tumbling during the jump. The first is that prior to the jump, locusts adjust the pitch of their body to move the center of mass closer to the intended thrust vector. The second is that contraction of the dorsolongitudinal muscles during the jump will produce torques that counter the torque produced by thrust. We found that locusts increased their take-off angle as the initial body pitch increased, and that little tumbling occurred for jumps that observed this relationship. Simulations of locust jumping demonstrated that a pitch versus take-off angle relationship that minimized tumbling in simulated jumps was similar to the relationship observed in live locusts. Locusts were strongly biased to pitch head-upward, and performed dorsiflexions far more often than ventral flexions. The direction and magnitude of tumbling could be controlled in simulations by adjusting the tension in the dorsolongitudinal muscles. These mechanisms allowed the simulations to match the data from the live animals. Control of tumbling was also found to influence the control of jump elevation. The bias to pitch head-upwards may have an evolutionary advantage when evading a predator and so make control of tumbling important for the locust.
Angiogenesis of the uterus and chorioallantois in the eastern water skinkEulamprus quoyii
Authors: Murphy Bridget F. , Parker Scott L. , Murphy Christopher R. , Thompson Michael B. 
Published: September 2010

SUMMARYWe have discovered a modification of the uterus that appears to facilitate maternal-fetal communication during pregnancy in the scincid lizard Eulamprus quoyii. A vessel-dense elliptical area (VDE) on the mesometrial side of the uterus expands as the embryo grows, providing a large vascular area for physiological exchange between mother and embryo. The VDE is already developed in females with newly ovulated eggs, and is situated directly adjacent to the chorioallantois of the embryo when it develops. It is likely that signals from the early developing embryo determine the position of the VDE, as the VDE is off-centre in cases where the embryo sits obliquely in the uterus. The VDE is not a modification of the uterus over the entire chorioallantoic placenta, as the VDE is smaller than the chorioallantois after embryonic stage 33, but expansion of the VDE and growth of the chorioallantois during pregnancy are strongly correlated. The expansion of the VDE is also strongly correlated with embryonic growth and increasing embryonic oxygen demand (). We propose that angiogenic stimuli are exchanged between the VDE and the chorioallantois in E. quoyii, allowing the simultaneous growth of both tissues.
Quantity of Immobilized Acid Phosphatase and Reaction Rate across Enzyme Membranes
Authors: Takeda Hideo , Tanaka Hiroki , Nomura Kazuo 
Published: September 2010

Abstract
Acid phosphatase from sweet potato was immobilized on the external-solution side surface of a perfluorocarboxylate ion-exchange membrane. Two membranes of different enzyme amounts were prepared without any crosslinking reagents. The effect of the immobilized-enzyme amount on the enzymatic reaction rate across the membrane was investigated for the hydrolysis of 4-nitrophenyl phosphate. The flux of the reaction product, 4-nitrophenol, was found to obey a Michaelis–Menten equation. As the amount of the immobilized enzyme increased, the Michaelis constant decreased whereas the maximum flux did not increase.
Determination of biological variation of α-fetoprotein and choriogonadotropin (β chain) in disease-free patients with testicular cancer
Authors: Trapé Jaume , Franquesa Josefina , Sala Maria , Domenech Montserrat , Montesinos Jesus , Catot Sílvia , Buxó Josep , Casado Esther , Fígols Cristina , Harillo Sílvia , Galobart Judit , Bella Meritxell 
Published: September 2010

Abstract

Background: Knowledge of biological variation (BV) is important for determining analytical goals and for establishing the magnitude of change between two consecutive measurements which indicate change in a patients' health status. The aim of this work is to determine the BV for total choriogonadotropin (β chain) (β-hCG) and α-fetoprotein (AFP) in patients diagnosed with testicular cancer but with no evidence of recurrence of disease.

Methods: We estimated BV from a mean of five consecutive measurements in 28 patients diagnosed with testicular cancer, 3 months after tumor resection or 4 months after complete treatment with chemotherapy. The mean sampling interval was 3 months.

Results: The mean concentrations of α-fetoprotein and choriogonadotropin (β chain) were 3.9 μg/L and 0.79 IU/L, respectively. Between-run analytical variation was 7.1% at 4.1 μg/L for α-fetoprotein, and 19% at 0.65 IU/L for choriogonadotropin (β chain). BV obtained for α-fetoprotein and choriogonadotropin (β chain) was 12.4% and 16.7%, respectively, and the reference change value (RCV) for one-tail showed 38.2% and 60.7% for α-fetoprotein and choriogonadotropin (β chain), respectively.

Conclusions: The estimation of BV allows us to calculate analytical goals and RCVs, necessary tools for the correct interpretation of serial measurements in the follow-up of patients.
Clin Chem Lab Med 2010;48:1799–801.
Locally Delivered Doxycycline as an Adjunct to Mechanical Debridement at Retreatment of Periodontal Pockets: Outcome at Furcation Sites
Authors: Tomasi Cristiano , Wennström Jan L. 
Published: September 2010

Background: The goal was to evaluate the clinical outcome of non‐surgical retreatment at molar furcation sites by ultrasonic debridement with or without adjunctive application of locally delivered doxycycline, and to explore factors affecting the healing results.Methods: This study involves 32 patients with chronic periodontitis, who received initial pocket/root debridement by ultrasonic instrumentation, followed by random assignment to retreatment of remaining pathologic sites at 3 months by ultrasonic instrumentation with or without adjunctive local application of an 8.8% doxycycline gel. Clinical examinations of plaque, probing depth (PD), relative attachment level, furcation involvement, and bleeding after furcation probing were performed initially, before retreatment at 3 months (baseline), and 3 and 9 months after retreatment. The primary efficacy variable was reduction in the degree of furcation involvement. A multilevel logistic model was used to evaluate the impact of patient and tooth site related factors on the main outcome variable.Results: The retreatment including locally delivered doxycycline resulted in closure of 50% of degree I furcation sites, compared to 29% for sites treated with mechanical debridement only (P >0.05). Of the degree II furcation sites, 17% in the test and 11% in the control group were reduced in depth (P >0.05). The logistic multilevel model with “furcation improvement” as the dichotomous outcome variable revealed that local application of doxycycline had no statistically significant effect. The odds ratio for “furcation improvement” was 0.80 (95% confidence interval [CI], 0.65 to 0.99) for 1‐mm increase of initial vertical PD, 0.36 (95% CI, 0.17 to 0.80) for initial furcation involvement degree II compared to degree I, and 0.24 (95% CI, 0.08 to 0.72) for smokers compared to non‐smokers.Conclusion: Improvement in molar furcation involvement after non‐surgical periodontal therapy was not enhanced by adjunctive locally applied doxycycline and negatively affected by increased vertical PD and tobacco smoking.
Managing Abandonment, Decommissioning, Remediation and Restoration throughout the E&P Lifecycle
Authors: Hoffmann Rob , Strong Jim 
Published: September 2010

Abstract
If retirement activities are deferred too late in the life of an exploration and production (E&P) asset, the number of retirement activities (i.e. well abandonment, facility decommissioning, site remediation, land restoration) could potentially exceed the funds, resources and time available. Large inventories of inactive assets (e.g. idle wells and facilities) carried long-term further compound the potential budgetary, resource, and schedule shortfall at end-of-life.
A set of operating practices has been developed to systematically manage asset retirement throughout an E&P asset's lifecycle, enabling completion of retirement activities at a rational pace in alignment with the business unit's cash flow profile, resource availability, and lifespan. These practices guide inventorying, prioritizing and managing abandonment-decommissioning candidates (e.g. wells, pipelines, and facilities designated for retirement or inactive long-term), remediation candidates (sites with potentially impacted environmental media; inactive pits) and restoration candidates (borrow pits or disturbed land designated for restoration or inactive long-term) as an integral component of the asset's business plan. Technical guidelines for suspension, abandonment, decommissioning, site assessment, remediation and restoration complement the operating practices by driving task execution to world-class technical standards.
Use of the operating practices described in this paper will position E&P business units to manage asset retirement progressively and perform the activities to world-class technical standards.
A Hierarchical Streamline-Assisted History Matching Approach with Global and Local Parameter Updates
Authors: Yin Jichao , Park Hanyoung , Datta-Gupta Akhil , King Michael J. , Choudhary Manoj K. 
Published: September 2010

Abstract
The effective strategies for traditional manual history matching commonly follow a structured approach with a sequence of adjustments from global to regional parameters followed by local changes in model properties, associated with matching for pressure (reservoir energy), flood front progression, and individual well performance. In contrast, many of the automatic history matching methods utilize parameter sensitivities or gradients to directly update the fine-scale reservoir properties, potentially combining elements at all of these scales. In this paper we present a hierarchical streamline-assisted history matching approach that emulates the traditional structured procedures. First, a probabilistic approach is used to understand the uncertainty in the large-scale static and dynamic parameters, and to calibrate these global parameters. In this global calibration, the intent is to develop multiple models that all sensibly match the field performance. This global calibration is followed by a streamline sensitivity-based deterministic model calibration for local permeability changes in which each of the distinct models created in the global match are history matched in additional detail.
In the probabilistic global calibration, design of experiments and response surface methodologies with evolutionary algorithms are used to calibrate the global parameters. Typical parameters are regional pore volume multipliers, regional vertical and areal transmissibility multipliers, fault transmissibilities and aquifer strength. Key global parameters are first identified via a sensitivity analysis and an initial ensemble of models that span these parameters is created. The cases studied in this sensitivity analysis are used to construct a proxy model using experimental design and response surface analysis. An improved genetic algorithm with heat-bath sampling is used to generate an updated ensemble of models conditioned to static MDT pressures and total liquid rates at the wells, corresponding to a traditional pressure history match. Next, each ensemble member is updated using water-cut, GOR and flowing BHP via sensitivity-based local permeability calibration. We utilize streamline-derived analytic sensitivities to determine the spatial distribution and magnitude of these local changes.
The proposed approach was tested by a 3D synthetic case and a field application. Our hierarchical approach appears to be stable in the sense that the local changes for permeability (inner loop) do not invalidate the pressure history match (outer loop). This is not entirely unexpected since the local permeability changes are regularized by a ‘norm’ constraint that minimizes deviations from the globally updated model. None the less, this is a very useful property in that it allows us to powerfully combine history matching procedures on global and local scales.
Health Aspects of Work in Extreme Climates within the E&P Industry: the Heat
Authors: Dahl-Hansen Erik , Barbey Alex , Arnulf Laurent , Covil Mike , de Jong Geert , Dugelay Francois , Jones Stephen , Jorgensen Knut , Keech Jim , Rodier Jaques , Ross Jonathon 
Published: September 2010

Abstract
The OGP Health Subcommittee has issued guidelines, which target both line management and the company health professionals, to reduce health risk while working in the heat.
Work in dry or moist heat poses a number of hazards
Health related problems due to the heat might appear at various temperatures. Although this document is intended primarily for desert and jungle regions, it is not limited only to these conditions.
Different aspects of preventing heat-related health problems are presented.
The brain cannot survive when its temperature exceeds 44-45°C (113 °F). When the blood's temperature rises above 37°C (98.6°F), special centres in the brain initiate the body's heat control mechanisms
Lack of water replacement, or dehydration, is the major factor in most heat disorders.
Drink regularly even if not thirsty. The routine use of salt tablets is not recommended.
The document gives general and specific advice on how to improve employee awareness through education and training. Recommendations for managing and reducing heat exposure on the work site and how to optimise the medical organisations are given.
Health problems due to extreme heat and humidity are defined and described in some detail. The heat may exacerbate psychological conditions. Conditions that are more thoroughly described are: transient heat fatigue, heat syncope, hyperthermia, heat cramp, heat exhaustion, hyperpyrexia or heat stroke, dehydration, muscle related problems and skin related problems.