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Sample records for cadherin-11 controls otolith

  1. Cell differentiation of pluripotent tissue sheets immobilized on supported membranes displaying cadherin-11.

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    Alexander Körner

    Full Text Available Investigating cohesive tissue sheets in controlled cultures still poses a challenge since the complex intercellular interactions are difficult to mimic in in vitro models. We used supported lipid membranes functionalized by the adhesive part of the extracellular domain of the cell adhesion molecule cadherin-11 for the immobilization of pluripotent tissue sheets, the animal cap isolated from Xenopus laevis blastula stage embryos. Cadherin-11 was bound via histidine tag to lipid membranes with chelator head groups. In the first step, quantitative functionalization of the membranes with cadherin-11 was confirmed by quartz crystal microbalance and high energy specular X-ray reflectivity. In the next step, animal cap tissue sheets induced to neural crest cell fate were cultured on the membranes functionalized with cadherin-11. The adhesion of cells within the cohesive tissue was significantly dependent on changes in lateral densities of cadherin-11. The formation of filopodia and lamellipodia in the cohesive tissue verified the viability and sustainability of the culture over several hours. The expression of the transcription factor slug in externally induced tissue demonstrated the applicability of lipid membranes displaying adhesive molecules for controlled differentiation of cohesive pluripotent tissue sheets.

  2. Otolith and Vertical Canal Contributions to Dynamic Postural Control

    Science.gov (United States)

    Black, F. Owen

    1999-01-01

    The objective of this project is to determine: 1) how do normal subjects adjust postural movements in response to changing or altered otolith input, for example, due to aging? and 2) how do patients adapt postural control after altered unilateral or bilateral vestibular sensory inputs such as ablative inner ear surgery or ototoxicity, respectively? The following hypotheses are under investigation: 1) selective alteration of otolith input or abnormalities of otolith receptor function will result in distinctive spatial, frequency, and temporal patterns of head movements and body postural sway dynamics. 2) subjects with reduced, altered, or absent vertical semicircular canal receptor sensitivity but normal otolith receptor function or vice versa, should show predictable alterations of body and head movement strategies essential for the control of postural sway and movement. The effect of altered postural movement control upon compensation and/or adaptation will be determined. These experiments provide data for the development of computational models of postural control in normals, vestibular deficient subjects and normal humans exposed to unusual force environments, including orbital space flight.

  3. Cadherin-11 modulates cell morphology and collagen synthesis in periodontal ligament cells under mechanical stress.

    Science.gov (United States)

    Feng, Lishu; Zhang, Yimei; Kou, Xiaoxing; Yang, Ruili; Liu, Dawei; Wang, Xuedong; Song, Yang; Cao, Haifeng; He, Danqing; Gan, Yehua; Zhou, Yanheng

    2017-03-01

    To examine the role of cadherin-11, an integral membrane adhesion molecule, in periodontal ligament cells (PDLCs) under mechanical stimulation. Human PDLCs were cultured and subjected to mechanical stress. Cadherin-11 expression and cell morphology of PDLCs were investigated via immunofluorescence staining. The mRNA and protein expressions of cadherin-11 and type I collagen (Col-I) of PDLCs were evaluated by quantitative real-time polymerase chain reaction and Western blot, respectively. Small interfering RNA was used to knock down cadherin-11 expression in PDLCs. The collagen matrix of PDLCs was examined using toluidine blue staining. Cadherin-11 was expressed in PDLCs. Mechanical stress suppressed cadherin-11 expression in PDLCs with prolonged force treatment time and increased force intensity, accompanied by suppressed β-catenin expression. Simultaneously, mechanical stress altered cell morphology and repressed Col-I expression in a time- and dose-dependent manner in PDLCs. Moreover, knockdown of cadherin-11 with suppressed β-catenin expression resulted in altered PDLC morphology and repressed collagen expression, which were consistent with the changes observed under mechanical stress. Results of this study suggest that cadherin-11 is expressed in PDLCs and modulates PDLC morphology and collagen synthesis in response to mechanical stress, which may play an important role in the homeostasis and remodeling of the PDL under mechanical stimulation.

  4. Otolith growth during hypergravity

    Science.gov (United States)

    Lychakov, Dmitri

    Background. It is suggested, that the weight of the otolith mass on the sensory epithelium is the direct regulating factor controlling the growth of the otolith via negative-feedback loop between the brain and the inner ear. This means that if the mass of the individual otolith will stand above the normal mass the afferent input arising from fish tilts will not match the expected responses based on the internal sensory model, and the feedback mechanism will slow down the otolith growth. This suggests that the altered gravity such as hyper- or microgravity can affect the normal otolith growth. Methods. Two experiments each lasted 121 and 128 days have been performed on the guppy larvae (n = 12/12 and 18/20; control/ experiment fish) raised from 10 days after birth within a centrifuge at ~2g hypergravity. The masses of utricilar, saccular and lagenar otoliths are analyzed. Results. There are no statistically significant differences between controls (1g) and experiments (2g) in masses and lengths of fishes, and in masses of uticular, saccular and lagenar otoliths. Conclusions. Otolith weight seems to be not involved in the feedback regulation of its growth. This conclusion is in accord with our previous conclusions based on results of space and centrifuge experiments on guppy larvae and Xenopus embryos (Lychakov, 2002). This work was partly supported by Russian grant RFFI 14-04-00601.

  5. ZAG-Otolith: Modification of Otolith-Ocular Reflexes, Motion Perception and Manual Control during Variable Radius Centrifugation Following Space Flight

    Science.gov (United States)

    Wood, S. J.; Clarke, A. H.; Rupert, A. H.; Harm, D. L.; Clement, G. R.

    2009-01-01

    Two joint ESA-NASA studies are examining changes in otolith-ocular reflexes and motion perception following short duration space flights, and the operational implications of post-flight tilt-translation ambiguity for manual control performance. Vibrotactile feedback of tilt orientation is also being evaluated as a countermeasure to improve performance during a closed-loop nulling task. METHODS. Data is currently being collected on astronaut subjects during 3 preflight sessions and during the first 8 days after Shuttle landings. Variable radius centrifugation is utilized to elicit otolith reflexes in the lateral plane without concordant roll canal cues. Unilateral centrifugation (400 deg/s, 3.5 cm radius) stimulates one otolith positioned off-axis while the opposite side is centered over the axis of rotation. During this paradigm, roll-tilt perception is measured using a subjective visual vertical task and ocular counter-rolling is obtained using binocular video-oculography. During a second paradigm (216 deg/s, <20 cm radius), the effects of stimulus frequency (0.15 - 0.6 Hz) are examined on eye movements and motion perception. A closed-loop nulling task is also performed with and without vibrotactile display feedback of chair radial position. PRELIMINARY RESULTS. Data collection is currently ongoing. Results to date suggest there is a trend for perceived tilt and translation amplitudes to be increased at the low and medium frequencies on landing day compared to pre-flight. Manual control performance is improved with vibrotactile feedback. DISCUSSION. One result of this study will be to characterize the variability (gain, asymmetry) in both otolithocular responses and motion perception during variable radius centrifugation, and measure the time course of postflight recovery. This study will also address how adaptive changes in otolith-mediated reflexes correspond to one's ability to perform closed-loop nulling tasks following G-transitions, and whether manual

  6. ADAM13 cleavage of cadherin-11 promotes CNC migration independently of the homophilic binding site.

    Science.gov (United States)

    Abbruzzese, Genevieve; Becker, Sarah F; Kashef, Jubin; Alfandari, Dominique

    2016-07-15

    The cranial neural crest (CNC) is a highly motile population of cells that is responsible for forming the face and jaw in all vertebrates and perturbing their migration can lead to craniofacial birth defects. Cell motility requires a dynamic modification of cell-cell and cell-matrix adhesion. In the CNC, cleavage of the cell adhesion molecule cadherin-11 by ADAM13 is essential for cell migration. This cleavage generates a shed extracellular fragment of cadherin-11 (EC1-3) that possesses pro-migratory activity via an unknown mechanism. Cadherin-11 plays an important role in modulating contact inhibition of locomotion (CIL) in the CNC to regulate directional cell migration. Here, we show that while the integral cadherin-11 requires the homophilic binding site to promote CNC migration in vivo, the EC1-3 fragment does not. In addition, we show that increased ADAM13 activity or expression of the EC1-3 fragment increases CNC invasiveness in vitro and blocks the repulsive CIL response in colliding cells. This activity requires the presence of an intact homophilic binding site on the EC1-3 suggesting that the cleavage fragment may function as a competitive inhibitor of cadherin-11 adhesion in CIL but not to promote cell migration in vivo. Copyright © 2015. Published by Elsevier Inc.

  7. Cadherin-11 is expressed in detrusor smooth muscle cells and myofibroblasts of normal human bladder.

    NARCIS (Netherlands)

    Kuijpers, K.A.J.; Heesakkers, J.P.; Jansen, C.F.J.; Schalken, J.A.

    2007-01-01

    OBJECTIVES: It has recently been found that detrusor smooth muscle cells and myofibroblasts are coupled via gap junctions. However, gap junctions cannot account for strong physical interaction between cells, which has prompted the search for intercellular adhesion molecules. Cadherin-11 is a

  8. Angiomotin is a novel component of cadherin-11/β-catenin/p120 complex and is critical for cadherin-11-mediated cell migration

    Science.gov (United States)

    Ortiz, Angelica; Lee, Yu-Chen; Yu, Guoyu; Liu, Hsuan-Chen; Lin, Song-Chang; Bilen, Melmet Asim; Cho, Hyojin; Yu-Lee, Li-Yuan; Lin, Sue-Hwa

    2015-01-01

    Loss of E-cadherin and up-regulation of mesenchymal cadherins, a hallmark of the epithelial–mesenchymal transition, contributes to migration and dissemination of cancer cells. Expression of human cadherin-11 (Cad11), also known as osteoblast cadherin, in prostate cancer increases the migration of prostate cancer cells. How Cad11 mediates cell migration is unknown. Using the human Cad11 cytoplasmic domain in pulldown assays, we identified human angiomotin (Amot), known to be involved in cell polarity, migration, and Hippo pathway, as a component of the Cad11 protein complex. Deletion analysis showed that the last C-terminal 10 amino acids in Cad11 cytoplasmic domain are required for Amot binding. Further, Cad11 preferentially interacts with Amot-p80 than Amot-p130 isoform and binds directly to the middle domain of Amot-p80. Cad11-Amot interaction affects Cad11-mediated cell migration, but not homophilic adhesion, as deletion of Amot binding motif of Cad11 (Cad11-ΔAmot) did not abolish Cad11-mediated cell–cell adhesion of mouse L cells, but significantly reduced Cad11-mediated cell migration of human C4-2B4 and PC3-mm2 prostate cancer cells and human HEK293T cells. Together, our studies identified Amot-p80 as a novel component of the Cad11 complex and demonstrated that Amot-p80 is critical for Cad11-mediated cell migration.—Ortiz, A., Lee, Y.-C., Yu, G., Liu, H.-C., Lin, S.-C., Bilen, M. A., Cho, H., Yu-Lee, L.-Y., Lin, S.-H. Angiomotin is a novel component of cadherin-11/β-catenin/p120 complex and is critical for cadherin-11-mediated cell migration. PMID:25466890

  9. Modification of Otolith-Ocular Reflexes, Motion Perception and Manual Control During Variable Radius Centrifugation Following Space Flight

    Science.gov (United States)

    Wood, Scott J.; Clarke, A. H.; Rupert, A. H.; Harm, D. L.; Clement, G. R.

    2009-01-01

    Two joint ESA-NASA studies are examining changes in otolith-ocular reflexes and motion perception following short duration space flights, and the operational implications of post-flight tilt-translation ambiguity for manual control performance. Vibrotactile feedback of tilt orientation is also being evaluated as a countermeasure to improve performance during a closed-loop nulling task. Data is currently being collected on astronaut subjects during 3 preflight sessions and during the first 8 days after Shuttle landings. Variable radius centrifugation is utilized to elicit otolith reflexes in the lateral plane without concordant roll canal cues. Unilateral centrifugation (400 deg/s, 3.5 cm radius) stimulates one otolith positioned off-axis while the opposite side is centered over the axis of rotation. During this paradigm, roll-tilt perception is measured using a subjective visual vertical task and ocular counter-rolling is obtained using binocular video-oculography. During a second paradigm (216 deg/s, less than 20 cm radius), the effects of stimulus frequency (0.15 - 0.6 Hz) are examined on eye movements and motion perception. A closed-loop nulling task is also performed with and without vibrotactile display feedback of chair radial position. Data collection is currently ongoing. Results to date suggest there is a trend for perceived tilt and translation amplitudes to be increased at the low and medium frequencies on landing day compared to pre-flight. Manual control performance is improved with vibrotactile feedback. One result of this study will be to characterize the variability (gain, asymmetry) in both otolith-ocular responses and motion perception during variable radius centrifugation, and measure the time course of post-flight recovery. This study will also address how adaptive changes in otolith-mediated reflexes correspond to one's ability to perform closed-loop nulling tasks following G-transitions, and whether manual control performance can be improved

  10. Post-transcriptional regulation of cadherin-11 expression by GSK-3 and beta-catenin in prostate and breast cancer cells.

    Directory of Open Access Journals (Sweden)

    Anne K Farina

    Full Text Available The cell-cell adhesion molecule cadherin-11 is important in embryogenesis and bone morphogenesis, invasion of cancer cells, lymphangiogenesis, homing of cancer cells to bone, and rheumatoid arthritis. However, very little is known about the regulation of cadherin-11 expression.Here we show that cell density and GSK-3beta regulate cadherin-11 levels in cancer cells. Inactivation of GSK3beta with lithium chloride or the GSK3 inhibitor BIO and GSK3beta knockdown with siRNA repressed cadherin-11 mRNA and protein levels. RNA Polymerase II chromatin immunoprecipitation experiments showed that inhibition of GSK3 does not affect cadherin-11 gene transcription. Although the cadherin-11 3'UTR contains putative microRNA target sites and is regulated by Dicer, its stability is not regulated by GSK3 inhibition or density. Our data show that GSK3beta regulates cadherin-11 expression in two ways: first a beta-catenin-independent regulation of cadherin-11 steady state mRNA levels, and second a beta-catenin-dependent effect on cadherin-11 3'UTR stability and protein translation.Cadherin-11 mRNA and protein levels are regulated by the activity of GSK3beta and a significant degree of this regulation is exerted by the GSK3 target, beta-catenin, at the level of the cadherin-11 3'UTR.

  11. Cadherin-11 regulates motility in normal cortical neural precursors and glioblastoma.

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    Jessica D Schulte

    Full Text Available Metastasizing tumor cells undergo a transformation that resembles a process in normal development when non-migratory epithelial cells modulate the expression of cytoskeletal and adhesion proteins to promote cell motility. Here we find a mesenchymal cadherin, Cadherin-11 (CDH11, is increased in cells exiting the ventricular zone (VZ neuroepithelium during normal cerebral cortical development. When overexpressed in cortical progenitors in vivo, CDH11 causes premature exit from the neuroepithelium and increased cell migration. CDH11 expression is elevated in human brain tumors, correlating with higher tumor grade and decreased patient survival. In glioblastoma, CDH11-expressing tumor cells can be found localized near tumor vasculature. Endothelial cells stimulate TGFβ signaling and CDH11 expression in glioblastoma cells. TGFβ promotes glioblastoma cell motility, and knockdown of CDH11 expression in primary human glioblastoma cells inhibits TGFβ-stimulated migration. Together, these findings show that Cadherin-11 can promote cell migration in neural precursors and glioblastoma cells and suggest that endothelial cells increase tumor aggressiveness by co-opting mechanisms that regulate normal neural development.

  12. Vestibular control of sympathetic activity. An otolith-sympathetic reflex in humans

    Science.gov (United States)

    Kaufmann, H.; Biaggioni, I.; Voustianiouk, A.; Diedrich, A.; Costa, F.; Clarke, R.; Gizzi, M.; Raphan, T.; Cohen, B.

    2002-01-01

    It has been proposed that a vestibular reflex originating in the otolith organs and other body graviceptors modulates sympathetic activity during changes in posture with regard to gravity. To test this hypothesis, we selectively stimulated otolith and body graviceptors sinusoidally along different head axes in the coronal plane with off-vertical axis rotation (OVAR) and recorded sympathetic efferent activity in the peroneal nerve (muscle sympathetic nerve activity, MSNA), blood pressure, heart rate, and respiratory rate. All parameters were entrained during OVAR at the frequency of rotation, with MSNA increasing in nose-up positions during forward linear acceleration and decreasing when nose-down. MSNA was correlated closely with blood pressure when subjects were within +/-90 degrees of nose-down positions with a delay of 1.4 s, the normal latency of baroreflex-driven changes in MSNA. Thus, in the nose-down position, MSNA was probably driven by baroreflex afferents. In contrast, when subjects were within +/-45 degrees of the nose-up position, i.e., when positive linear acceleration was maximal along the naso-ocipital axis, MSNA was closely related to gravitational acceleration at a latency of 0.4 s. This delay is too short for MSNA changes to be mediated by the baroreflex, but it is compatible with the delay of a response originating in the vestibular system. We postulate that a vestibulosympathetic reflex, probably originating mainly in the otolith organs, contributes to blood pressure maintenance during forward linear acceleration. Because of its short latency, this reflex may be one of the earliest mechanisms to sustain blood pressure upon standing.

  13. Cadherin-11 Overexpression Induces Extracellular Matrix Remodeling and Calcification in Mature Aortic Valves.

    Science.gov (United States)

    Sung, Derek C; Bowen, Caitlin J; Vaidya, Kiran A; Zhou, Jingjing; Chapurin, Nikita; Recknagel, Andrew; Zhou, Bin; Chen, Jonathan; Kotlikoff, Michael; Butcher, Jonathan T

    2016-08-01

    Calcific aortic valve (AoV) disease is a significant clinical problem for which the regulatory mechanisms are poorly understood. Enhanced cell-cell adhesion is a common mechanism of cellular aggregation, but its role in calcific lesion formation is not known. Cadherin-11 (Cad-11) has been associated with lesion formation in vitro, but its function during adult valve homeostasis and pathogenesis is not known. This study aims to elucidate the specific functions of Cad-11 and its downstream targets, RhoA and Sox9, in extracellular matrix remodeling and AoV calcification. We conditionally overexpressed Cad-11 in murine heart valves using a novel double-transgenic Nfatc1(Cre);R26-Cad11(TglTg) mouse model. These mice developed hemodynamically significant aortic stenosis with prominent calcific lesions in the AoV leaflets. Cad-11 overexpression upregulated downstream targets, RhoA and Sox9, in the valve interstitial cells, causing calcification and extensive pathogenic extracellular matrix remodeling. AoV interstitial cells overexpressing Cad-11 in an osteogenic environment in vitro rapidly form calcific nodules analogous to in vivo lesions. Molecular analyses revealed upregulation of osteoblastic and myofibroblastic markers. Treatment with a Rho-associated protein kinase inhibitor attenuated nodule formation, further supporting that Cad-11-driven calcification acts through the small GTPase RhoA/Rho-associated protein kinase signaling pathway. This study identifies one of the underlying molecular mechanisms of heart valve calcification and demonstrates that overexpression of Cad-11 upregulates RhoA and Sox9 to induce calcification and extracellular matrix remodeling in adult AoV pathogenesis. The findings provide a potential molecular target for clinical treatment. © 2016 American Heart Association, Inc.

  14. Bottomfish Otolith Archive

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Ryan Nichols (FBSAB LHP) collected this data set and it contains information on fish otoliths collected from previous research cruises and stored in Aiea Research...

  15. Umbilical Cord-Derived Mesenchymal Stem Cells Inhibit Cadherin-11 Expression by Fibroblast-Like Synoviocytes in Rheumatoid Arthritis

    Directory of Open Access Journals (Sweden)

    Cheng Zhao

    2015-01-01

    Full Text Available This study aimed to determine whether umbilical cord-derived mesenchymal stem cells (UCMSC regulate Cadherin-11 (CDH11 expression by fibroblast-like synoviocytes (FLS in rheumatoid arthritis (RA. FLS were isolated from the synovium of RA and osteoarthritis (OA patients. FLS from RA patients were cocultured with UCMSC in a transwell system. CDH11 mRNA levels in FLS were tested, and levels of soluble factors expressed by UCMSC, such as indoleamine 2,3-dioxygenase (IDO, hepatocyte growth factor (HGF, and interleukin- (IL- 10, were determined. IDO, HGF, and IL-10 were upregulated in cocultures, so that appropriate inhibitors were added before determination of CDH11 expression. The effects of UCMSC on arthritis were investigated in the collagen-induced arthritis (CIA model in Wistar rats. FLS from RA patients expressed higher CDH11 levels than those from OA patients, and this effect was suppressed by UCMSC. The inhibitory effect of UCMSC on CDH11 expression by FLS was abolished by suppression of IL-10 activity. CDH11 expression in synovial tissues was higher in the context of CIA than under basal conditions, and this effect was prevented by UCMSC administration. IL-10 mediates the inhibitory effect of UCMSC on CDH11 expression by FLS, and this mechanism might be targeted to ameliorate arthritis.

  16. OTOLITHS AND THEIR APPLICATIONS IN FISHERY SCIENCE

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    Paola Rodriguez Mendoza

    2006-07-01

    Full Text Available Otoliths are structures located in the inner ear cavity of all teleost fish and serve as a balance organ and also aid in hearing. They have been used traditionally to obtain information about the taxon, age and size of fishes. This is very important because age, growth rate, and mortality rate are three of the most influential life history characteristics controlling the productivity of fish populations. Besides age and growth determination, otoliths have been the object of study in many different fields, such as fish biology (hearing and balance in fishes, larval fish ecology, species identification, fish stock identification and environmental reconstruction of the fish habitat. Thus, the purpose of this paper is to provide an overview of the traditional and current applications of the otoliths. Also, a short description of the traditional methods for age determination is included.

  17. Fish otolith biomineralization process: first investigations about organic matrix and growth of Triglidae (Scorpaeniformes otoliths

    Directory of Open Access Journals (Sweden)

    Stefano Montanini

    2015-11-01

    Full Text Available Otolith formation involves rhythmic variations in the deposition and size of organic matrix framework and carbonate crystals, resulting in the formation of macroscopic translucent and opaque rings and microscopic zonations (growth increments (Morales Nin, 2000. As in most biominerals, the otolith matrix forms only 2-3 % of its weight, but it is admitted that it has a considerable importance in the otolith crystallization processes of nucleation, growth, orientation and growth control. The goal of this study is to characterize the matrix protein composition in the otoliths of Triglidae (Scorpaeniformes as a first step to understand molecular mechanisms of otolith formation according to biology and ecology of the species. In particular 500 sagittal otoliths from six gurnard species were analysed: Chelidonichthys cuculus, C. lucerna, Eutrigla gurnardus, Lepidotrigla cavillone, L. dieuzeidei and Trigloporus lastoviza. Protein contents were estimated by Bradford method and the urea 8 M extracts were loaded into a polyacrylamide gel, separated by SDS page and detected by Silver staining (Sigma followed the protocol of Borelli et al. (2001 with some modifications regarding protein precipitation that was enhanced by using TCA, trichloroacetic acid, 100% w/v. The urea soluble fractions revealed a unique large band around 50-55 kDa. Another common clear band was visible at the top of the separating gel (proteins >300/350 kDa unable to enter into the pores of polyacrylamide gels (12%. The complexity of the protein mixtures was investigated by 2-D electrophoresis (Gel TGX 4-20%; proteins were separated on the basis of both isoelectric point (pI and molecular size. A common protein pattern of 50-75 kDa were found in all gurnards showing a similar composition of organic matter even if the 2-D maps of otolith samples showed specie-specific variation in acid protein fractions in all the pairwise comparison. This result confirmed that the amino acid composition

  18. High‐resolution stock discrimination of Atlantic herring (Clupea harengus) based on otolith shape, microstructure, and genetic markers

    DEFF Research Database (Denmark)

    Mosegaard, Henrik; Worsøe Clausen, Lotte; Bekkevold, Dorte

    2012-01-01

    different populations of Atlantic herring (Clupea harengus) in the western Baltic and adjacent waters. We analyse a baseline (spawning individuals from several populations validated by genetic markers) for separation of adult herring (2+) based on otolith shape and juveniles using genetically validated...... otolith shape characteristics as separation parameters. Otolith shape was found to clearly discriminate between individuals at all ages from different spawning populations. The identified distances between populations based on otolith shape matched previously obtained genetic distances and were, when...... between populations, which suggest genetic control as well. Thus otolith shape serves as a population marker, suitable for individual assignment. Here we use otolith morphological characteristics (otolith shape and larval otolith microstructure) combined with genetic markers to discriminate between...

  19. Swimming Behavior and Calcium Incorporation into inner Ear Otoliths of Fish after vestibular Nerve Transection

    Science.gov (United States)

    Edelmann, E.; Anken, R.; Rahmann, H.

    Previous investigations on neonate swordtail fish (Xiphophorus helleri) revealed that otolithic calcium incorporation (visualized using the calcium-tracer alizarin- complexone) and thus otolith growth had ceased after nerve transection, supporting a hypothesis according to which the gravity-dependent otolith growth is regulated neuronally. Subsequent investigations on larval cichlid fish (Oreochromis mossambicus) yielded contrasting results, repeatedly depending on the particular batch of cichlids investigated: Like neonate swordtails, type I cichlids revealed a stop of calcium incorporation after unilateral vestibular nerve transection. Their behaviour after transection was normal and the otolithic calcium incorporation in controls of the same batch was symmetrical. In type II cichlids, however, vestibular nerve transection had no effect on otolithic calcium incorporation. They behaved kinetotically after transection (this kind of kinetosis was qualitatively similar to the swimming behaviour exhibited by larval cichlids during microgravity in the course of parabolic aircraft flights). The otolithic calcium incorporation in control animals was asymmetrical. These results stongly suggest that the effects of vestibular nerve transection as well as the efficacy of the mechanism, which regulates otolith growth/otolithic calcium incorporation, are - depending on the particular batch of animals - genetically predispositioned. Thus, it is assumed that the mechanisms regulating otolith growth and equlibibrium differ in the two types of cichlid fish. This work was financially supported by the German Aerospace Center (DLR) e.V. (FKZ: 50 WB 9997).

  20. Swimming behaviour and calcium incorporation into inner ear otoliths of fish after vestibular nerve transection

    Science.gov (United States)

    Edelmann, E.; Anken, R. H.; Rahmann, H.

    2004-01-01

    Previous investigations on neonate swordtail fish (Xiphophorus helleri) revealed that otolithic calcium incorporation (visualized using the calcium tracer alizarin complexone) and thus otolith growth had ceased after nerve transection, supporting a hypothesis according to which the gravity-dependent otolith growth is regulated neuronally. Subsequent investigations on larval cichlid fish (Oreochromis mossambicus) yielded contrasting results, repeatedly depending on the particular batch of cichlids investigated. Like most neonate swordtails, Type I cichlids revealed a stop of calcium incorporation after unilateral vestibular nerve transection. Their behaviour after transection was normal, and the otolithic calcium incorporation in controls of the same batch was symmetric. In Type II cichlids, however, vestibular nerve transection had no effect on otolithic calcium incorporation. They behaved kinetotically after transection (this kind of kinetosis was qualitatively similar to the swimming behaviour exhibited by larval cichlids during microgravity in the course of parabolic aircraft flights). The otolithic calcium incorporation in control animals was asymmetric. These results show that the effects of vestibular nerve transection as well as the efficacy of the mechanism, which regulates otolith growth/otolithic calcium incorporation, are - depending on the particular batch of animals - genetically predispositioned. In conclusion, the regulation of otolithic calcium incorporation is guided neuronally, in part via the vestibular nerve and, in part, via a further pathway, which remains to be addressed in the course of future investigations.

  1. Restricted fish feeding reduces cod otolith opacity

    DEFF Research Database (Denmark)

    Høie, H.; Folkvord, A.; Mosegaard, Henrik

    2008-01-01

    in otolith opacity were found between individual fish both within groups and between groups. In two of the three groups significantly more translucent otolith material was deposited in response to reduced feeding. Our results show that variations in feeding and hence fish growth resulted in variation......The purpose of this work was to examine the effect of reduced feeding and constant temperature on cod otolith opacity. Three groups of juvenile cod were given restricted food rations at different times for 4 months, resulting in depressed somatic growth. Otolith opacity was measured on pictures...... of the otolith sections. The otolith carbonate deposited during the experimental period was generally opaque compared to the more translucent otolith material deposited prior to and after the experimental period, when the fish were kept in a pond and in sea-cages at higher temperatures. Large variations...

  2. Clinical verification of a unilateral otolith test

    Science.gov (United States)

    Wetzig, J.; Hofstetter-Degen, K.; Maurer, J.; von Baumgarten, R. J.

    In a previous study 13 we reported promising results for a new test to differentiate in vivo unilateral otolith functions. That study pointed to a need for further validation on known pathological cases. In this presentation we will detail the results gathered on a group of clinically verified vestibular defectives (verum) and a normal (control) group. The subjects in the verum group were former patients of the ENT clinic of the university hospital. These subjects had usually suffered from neurinoma of the VIIth cranial nerve or inner ear infections. All had required surgical intervention including removal of the vestibular system. The patients were contacted usually two or more years postoperatively. A group of students from the pre- and clinical phase of medical training served as control. Both groups were subjected to standardized clinical tests. These tests served to reconfirm the intra- or postoperative diagnosis of unilateral vestibular loss in the verum group. In the control group they had to establish the normalcy of the responses of the vestibular system. Both groups then underwent testing on our exccentric rotary chair in the manner described before 13. Preliminary results of the trials indicate that this test may indeed for the first time offer a chance to look at isolated otolith apparati in vivo.

  3. Otolithic apparatus of tetrapods after space flight

    Science.gov (United States)

    Lychakov, Dmitri

    In vertebrates the otolithic membrane is formed of three components: the gelatinous layer, the subcupular meshwork and the otolithic apparatus (Fermin et al., 1998; Lim, 1974; Lindeman, 1969; Lychakov, 1988, 2002). The otolithic apparatus consists of a set of small crystalline otoconia (Tetrapoda), or a single large crystalline otolith (Teleostei). Despite similar functions, the otoconia (Tetrapoda) and otolith otolithic apparatus differ significantly in their embryogenesis, postembryonic growth, chemical composition, etc. It may be suggested that the gravitational challenges may have different effects on otoconia or otoliths. Unfortunately, we have only a few quantitative data on structural adaptation of tetrapod otolithic apparatus to microgravity (Lychakov, 2002; Lychakov, Lavrova,1985; Wiederhold et al., 1997). The BION-M1 provides an opportunity for a quantitative morphological analysis of otolithic apparatus of adult mice exposed to 30 days in a biosatellite on orbit. We expect to analyse otoconia of utriculus and sacculus. Our principal aims are to investigate the morphological characteristics of otoconia. We expect to get novel insights in microgravity induced otoconia adaptation of tetrapods. This work was partly supported by Russian grant RFFI 14-04-00601.

  4. Trend of Cadherin-11 expression and its impact on cartilage degradation in the temporomandibular joints of guinea pigs with spontaneous osteoarthritis.

    Science.gov (United States)

    Wu, Mengjie; Lu, Haiping; Yu, Fengyang; Zhou, Yiqun

    2016-08-01

    This study aims to investigate spatial and temporal changes in cadherin-11 (CAD-11) expression and their effects on cartilage degeneration in the temporomandibular joint (TMJ) of guinea pigs with spontaneous osteoarthritis (OA). Dunkin-Hartley (DH) and Bristol strain 2 (BS2) guinea pigs at ages of 1, 3, 6, 9, and 12 months were categorized into two groups and analyzed. The bilateral TMJ condyles of DH and BS2 guinea pigs were harvested and fixed. The distribution and expression profiles of CAD-11, collagen type II, and matrix metalloproteinase 3 (MMP-3) were detected by immunohistological assays. Histological micrographs of the condyle cartilage were obtained and analyzed. Osteoarthritis can be spontaneously induced by mechanical stress in DH guinea pigs. The main histopathological changes in the TMJ structure and increased expression of MMP-3 occurred within 6-9 months of ages in DH guinea pigs with spontaneous OA. By contrast, minimal to mild cartilage degradations were observed in the TMJ of BS2 guinea pigs even at the age of 12 months. From as early as 3 months of age, the expression levels of CAD-11 were upregulated in the TMJ of DH guinea pigs compared with those in BS2 animals. CAD-11 expression differed between the two groups at 12 months of age. Increased CAD-11 expression within cartilage is associated with the development and progression of OA between the two strains of guinea pigs. Therefore, CAD-11 expression in TMJ could be an important predisposing factor for the development of spontaneous OA. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  5. The ectodomain of cadherin-11 binds to erbB2 and stimulates Akt phosphorylation to promote cranial neural crest cell migration.

    Directory of Open Access Journals (Sweden)

    Ketan Mathavan

    Full Text Available During development, a multi-potent group of cells known as the cranial neural crest (CNC migrate to form craniofacial structures. Proper migration of these cells requires proteolysis of cell adhesion molecules, such as cadherins. In Xenopus laevis, preventing extracellular cleavage of cadherin-11 impairs CNC migration. However, overexpression of the soluble cleavage product (EC1-3 is capable of rescuing this phenotype. The mechanism by which EC1-3 promotes CNC migration has not been investigated until now. Here we show that EC1-3 stimulates phosphorylation of Akt, a target of PI3K, in X.laevis CNC. Through immunoprecipitation experiments, we determined that EC1-3 interacts with all ErbB receptors, PDGFRα, and FGFR1. Of these receptors, only ErbB2 was able to produce an increase in Akt phosphorylation upon treatment with a recombinant EC1-3. This increase was abrogated by mubritinib, an inhibitor of ErbB2. We were able to recapitulate this decrease in Akt phosphorylation in vivo by knocking down ErbB2 in CNC cells. Knockdown of the receptor also significantly reduced CNC migration in vivo. We confirmed the importance of ErbB2 and ErbB receptor signaling in CNC migration using mubritinib and canertinib, respectively. Mubritinib and the PI3K inhibitor LY294002 significantly decreased cell migration while canertinib nearly prevented it altogether. These data show that ErbB2 and Akt are important for CNC migration and implicate other ErbB receptors and Akt-independent signaling pathways. Our findings provide the first example of a functional interaction between the extracellular domain of a type II classical cadherin and growth factor receptors.

  6. Unilateral otolith centrifugation by head tilt

    NARCIS (Netherlands)

    Winters, S.M.; Bos, J.E.; Klis, S.F.L.

    2014-01-01

    BACKGROUND: To test for otolith asymmetries, several studies described horizontal translation of the body and head en bloc during fast vertical axis rotation. This stimulus causes one otolithic organ to rotate on-axis, and the other to experience centripetal acceleration. OBJECTIVE: To test a new,

  7. Effects of ocean acidification on the calcification of otoliths of larval Atlantic cod, Gadus morhua L.

    Science.gov (United States)

    Maneja, R. H.; Frommel, A. Y.; Geffen, A. J.; Folkvord, A.; Piatkowski, U.; Chang, M. Y.; Clemmesen, C.

    2012-04-01

    The aragonitic calcium carbonate composition of the otoliths of teleost fishes could bring the organism in direct risk to ocean acidification. The potential effects of increase in atmospheric CO2 on the calcification of the otoliths were investigated by rearing Atlantic cod larvae (Gadus morhua L.) in three pCO2 concentrations, control-370, medium-1800, and high-4200 ppm from March to May 2010. Hypercalcification of otoliths were observed from 7 to 46-dph cod larvae cultured at elevated pCO2 concentrations. The sagittae and lapilli were largest at the high pCO2 treatment followed by medium and control with the biggest difference (83.8%) in mean otolith (sagitta) surface area at 32-dph between the high and control groups. The shift in the growth rates of the sagittae and lapilli also occurred much earlier in the high treatment with the growth of the sagitta surpassing that of the lapillus already at 32-dph. On the other hand, Atlantic cod larvae showed no trends in fluctuating asymmetry of the otoliths vis-a-vis the increase in otolith growth from elevated pCO2.

  8. Decreased otolith-mediated vestibular response in 25 astronauts induced by long-duration spaceflight.

    Science.gov (United States)

    Hallgren, Emma; Kornilova, Ludmila; Fransen, Erik; Glukhikh, Dmitrii; Moore, Steven T; Clément, Gilles; Van Ombergen, Angelique; MacDougall, Hamish; Naumov, Ivan; Wuyts, Floris L

    2016-06-01

    The information coming from the vestibular otolith organs is important for the brain when reflexively making appropriate visual and spinal corrections to maintain balance. Symptoms related to failed balance control and navigation are commonly observed in astronauts returning from space. To investigate the effect of microgravity exposure on the otoliths, we studied the otolith-mediated responses elicited by centrifugation in a group of 25 astronauts before and after 6 mo of spaceflight. Ocular counterrolling (OCR) is an otolith-driven reflex that is sensitive to head tilt with regard to gravity and tilts of the gravito-inertial acceleration vector during centrifugation. When comparing pre- and postflight OCR, we found a statistically significant decrease of the OCR response upon return. Nine days after return, the OCR was back at preflight level, indicating a full recovery. Our large study sample allows for more general physiological conclusions about the effect of prolonged microgravity on the otolith system. A deconditioned otolith system is thought to be the cause of several of the negative effects seen in returning astronauts, such as spatial disorientation and orthostatic intolerance. This knowledge should be taken into account for future long-term space missions. Copyright © 2016 the American Physiological Society.

  9. Radiocarbon Values From Otoliths of Regional Bottomfishes

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data set contains bomb radiocarbon dating of opakapaka (Pristipomoides filamentosus) otoliths from recent and archival collections (1978-2008). Specimens were...

  10. Effect of ocean acidification on otolith development in larvae of a tropical marine fish

    Directory of Open Access Journals (Sweden)

    P. L. Munday

    2011-06-01

    Full Text Available Calcification in many invertebrate species is predicted to decline due to ocean acidification. The potential effects of elevated CO2 and reduced carbonate saturation state on other species, such as fish, are less well understood. Fish otoliths (earbones are composed of aragonite, and thus, might be susceptible to either the reduced availability of carbonate ions in seawater at low pH, or to changes in extracellular concentrations of bicarbonate and carbonate ions caused by acid-base regulation in fish exposed to high pCO2. We reared larvae of the clownfish Amphiprion percula from hatching to settlement at three pHNBS and pCO2 levels (control: ~pH 8.15 and 404 μatm CO2; intermediate: pH 7.8 and 1050 μatm CO2; extreme: pH 7.6 and 1721 μatm CO2 to test the possible effects of ocean acidification on otolith development. There was no effect of the intermediate treatment (pH 7.8 and 1050 μatm CO2 on otolith size, shape, symmetry between left and right otoliths, or otolith elemental chemistry, compared with controls. However, in the more extreme treatment (pH 7.6 and 1721 μatm CO2 otolith area and maximum length were larger than controls, although no other traits were significantly affected. Our results support the hypothesis that pH regulation in the otolith endolymph can lead to increased precipitation of CaCO3 in otoliths of larval fish exposed to elevated CO2, as proposed by an earlier study, however, our results also show that sensitivity varies considerably among species. Importantly, our results suggest that otolith development in clownfishes is robust to even the more pessimistic changes in ocean chemistry predicted to occur by 2100.

  11. Estimating population age structure using otolith morphometrics

    DEFF Research Database (Denmark)

    Doering-Arjes, P.; Cardinale, M.; Mosegaard, Henrik

    2008-01-01

    known-age fish individuals. Here we used known-age Atlantic cod (Gadus morhua) from the Faroe Bank and Faroe Plateau stocks. Cod populations usually show quite large variation in growth rates and otolith shape. We showed that including otolith morphometrics into ageing processes has the potential...... populations. The intercalibration method was successful but generalization from one stock to another remains problematic. The development of an otolith growth model is needed for generalization if an operational method for different populations is required in the future....... to make ageing objective, accurate, and fast. Calibration analysis indicated that a known-age sample from the same population and environment is needed to obtain robust calibration; using a sample from a different stock more than doubles the error rate, even in the case of genetically highly related...

  12. Fish Otolith Growth in 1g and 3g Depends on the Gravity Vector

    Science.gov (United States)

    Anken, R. H.; Werner, K.; Breuer, J.; Rahmann, H.

    Size and asymmetry (size difference between the left and the right side) as well as calcium (Ca) content of inner ear otoliths of larval cichlid fish Oreochromis mossambicus were determined after a long-term stay at hypergravity conditions (3g; centrifuge). Both utricular and saccular otoliths (lapilli and sagittae, respectively) were significantly smaller after hyper-g exposure as compared to parallely raised 1g-control specimens and the absolute amount of otolith-Ca was diminished. The asymmetry of sagittae was significantly increased in the experimental animals, whereas the respective asymmetry concerning lapilli was markedly decreased. In the course of another experiment, larvae were raised in aquarium hatch baskets, from which one was placed directly above aeration equipment, which resulted in random water circulation shifting the fish around (``shifted'' specimens). The lapillar asymmetry of the ``stationary'' specimens showed a highly significant increase during early development when larvae were forced to lay on their sides due to their prominent yolk-sacs. In later developmental stages, when they began to swim freely, a dramatic decrease in lapillar asymmetry was apparent. Taken together with own previous findings according to which otolith growth stops after vestibular nerve transection, the results presented here suggest that the growth and the development of bilateral asymmetry of otoliths is guided by the environmental gravity vector, obviously involving a feedback loop between the brain and the inner ear

  13. Ontogenetic development of otoliths in Alligator Gar

    Science.gov (United States)

    Long, James M.; Snow, Richard A.

    2016-01-01

    The Alligator Gar Atractosteus spatula is a species of conservation concern throughout its range, and better definition of otoliths during early development would aid understanding its life history and ecology. We conducted X-ray computed tomography scans, scanning electron microscopy, and light microscopy to examine the three pairs of otoliths and how they developed over time in relation to fish size and age. The sagittae are the largest, possessing distinct dorsal and ventral lobes covered with small otoconia concentrated in the sulcul region. The sagittae exhibited allometric growth, increasing more rapidly in the ventral lobe than in the dorsal. The asterisci were smaller and also exhibited small otoconia on their surface, but much less than the sagittae. The lapilli were oriented laterally, in contrast to the sagittae and asterisci, which were oriented vertically, with a hump on the dorsum and very large otoconia on the lateral surface that appeared to fuse into the main otolith as the fish grew. Based on size measurements and ring counts in all three pairs of otoliths from 101 known-age Alligator Gar sampled weekly through 91 d after hatch, we developed regression models to examine otolith growth and predict age. All relationships were significant and highly explanatory, but the strongest relationships were between otolith and fish size (for measurements from sagittae) and for age predictions from the lapillus. Age prediction models all resulted in a slope near unity, indicating that ring deposition occurred approximately daily. The first ring in sagittae and lapilli corresponded to swim-up, whereas the first ring formed in asterisci approximately 8 d after swim-up. These results fill a gap in knowledge and can aid understanding of evolutionary processes as well as provide useful information for management and conservation.

  14. Fish Otoliths as indicators: results of the V International Otolith Symposium (IOS2014

    Directory of Open Access Journals (Sweden)

    Audrey J. Geffen

    2015-11-01

    The traditional approach of using calcified tissues to determine fish age and therefore to determine the fish population structure has been augmented by new applications to address questions of population connectivity, migrations, and trophic ecology. These tools have become increasingly important as we transition to spatially explicit and ecosystem-level management tools. They are now extended to applications related to spatial use (essential habitats and to the use of otoliths as a record of past and present environmental conditions. Otoliths are valuable as individual bio-recorders, and – as demonstrated in the variety of presentations at the symposium – also as indicators for higher levels of organisation. The increased appreciation for otolith archives was also apparent; taking advantage of the extended otolith sampling for stock assessment and providing ample collections from different species, as well as from the fossil records.

  15. The OTOLITH Experiment - Assessment of Otolith Function During Postflight Re-adaption

    Science.gov (United States)

    Clarke, A. H.; Wood, S. J.; Schoenfeld, U.

    2010-01-01

    The ongoing "Otolith" experiment is designed to comprehensively assess the otolith function during the re-adaptation phase after spaceflight. The novel protocol includes unilateral testing of each of the two otolith organs the utricle and the saccule. To assess utricle function, the otolith-ocular response (OOR) and the subjective visual vertical (SVV) are measured during unilateral centrifugation, which permits independent stimulation of the right and left ear. Measurement of the unilateral otolith-ocular response (uOOR) yields information on the response behaviour of the right and left peripheral utricles, whereas the SVV reflects the behaviour of the entire pathway from the peripheral otolith receptors to the vestibular cortex. Thus, by comparative evaluation of the results from the two tests, the degree of peripheral versus central adaptation during the post-flight period can be determined. To assess unilateral saccule function, vestibular evoked myogenic potentials (VEMP) are recorded. Since the saccules are predominantly aligned to gravity, and interplay with the antigravity muscles, it is hypothesised that these potentials shall be altered after spaceflight. To date the study has been conducted with 5 of a planned 8 short-flight Shuttle astronauts. Preliminary results will be discussed together with those from clinical studies of dizziness patients, where the same test protocol is employed. ACKNOWLEDGEMENT This work is supported by the German Aerospace Center (Grant DLR W130729) and is conducted under the auspices of ESA, in cooperation with NASA.

  16. Can analysis of Platichthys flesus otoliths provide relevant data on historical metal pollution in estuaries? Experimental and in situ approaches

    Energy Technology Data Exchange (ETDEWEB)

    Selleslagh, Jonathan, E-mail: Jonathan.Selleslagh@u-bordeaux.fr [Université de Bordeaux, CNRS, UMR EPOC 5805, Station Marine d' Arcachon, place du docteur Peyneau, 33120 Arcachon (France); Echard, Aurélie [IRSTEA Centre de Bordeaux, unité EABX, 50 avenue de Verdun, 33612 Cestas (France); Pécheyran, Christophe [Université de Pau et des pays de l' Adour, CNRS, LCABIE-IPREM UMR 5254, 64053 Pau (France); Baudrimont, Magalie [Université de Bordeaux, CNRS, UMR EPOC 5805, Station Marine d' Arcachon, place du docteur Peyneau, 33120 Arcachon (France); Lobry, Jérémy; Daverat, Françoise [IRSTEA Centre de Bordeaux, unité EABX, 50 avenue de Verdun, 33612 Cestas (France)

    2016-07-01

    Despite recent efforts to manage them more efficiently, estuaries are natural sinks for a wide range of metal contaminants, many of which accumulate at potentially toxic concentrations for fish populations, posing a threat to recruitment and stocks. While analysis of metal concentrations in soft tissue and water samples calls for continuous and long-term sampling operations, the use of otoliths to study metal pollution may be one way of providing a historical record of pollutant exposure. In this study, we examine the potential use of otoliths as natural tracers of metal contamination. A “cocktail” of different metals (Cd, Pb and Ni) was used to test bio-accumulation in otoliths and tissue (liver, kidney, muscle and gills) extracted from juvenile flounder (Platichthys flesus). Assessment took place under controlled conditions over a three month period, with water exposure concentrations increasing every 3 weeks. The concentrations used were natural (T1), X5 (T2), X10 (T3), and null (T4). Chemical analyses were carried out using an inductively coupled plasma optical emission spectrometer ICP-OES and atomic absorption spectrometer AAS for water and tissue, while otolith microchemistry analyses were performed using a femtosecond laser ablation-high resolution inductively coupled plasma mass spectrometer (fsLA-ICP-MS-HR). Significant differences between control and exposed individuals, as well as an increase in metal concentrations according to exposure level, were observed in all tissues except in muscle tissue. Significant increases in Pb were also detected in contaminated fish otoliths compared with control specimens, with the highest concentrations occurring in T3. Cartographies of Pb distribution in otoliths of both control and contaminated fish only showed high concentrations of Pb at the edge of contaminated fish otoliths, indicating an accumulation of metal during the experiment. Although the relationships between exposure level and Pb concentration in

  17. Effect of betel nut chewing on the otolithic reflex system.

    Science.gov (United States)

    Lin, Chuan-Yi; Young, Yi-Ho

    2017-01-01

    This study investigated the effect of betel nut chewing on the otolithic reflex system. Seventeen healthy volunteers without any experience of chewing betel nut (fresh chewers) and 17 habitual chewers underwent vital sign measurements, ocular vestibular-evoked myogenic potential (oVEMP), and cervical VEMP (cVEMP) tests prior to the study. Each subject then chewed two pieces of betel nut for 2min (dosing). The same paradigm was repeated immediately, 10min, and 20min after chewing. On a different day, 10 fresh chewers masticated chewing gum as control. Fresh chewers exhibited significantly decreased response rates of oVEMP (53%) and cVEMP (71%) after dosing compared with those from the predosing period. These abnormal VEMPs returned to normal 20min after dosing. In contrast, 100% response rates of oVEMP and cVEMP were observed before and after masticating chewing gum. In habitual chewers, the response rates of oVEMP and cVEMP were 32% and 29%, respectively, 20min after dosing. Chewing betel nuts induced a transient loss of the otolithic reflexes in fresh chewers but may cause permanent loss in habitual chewers. Chewing betel nuts can cause a loss of otholitic reflex function. This creates a risk for disturbed balance and malfunction, for instance, during driving. Copyright © 2016 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  18. Argon laser irradiation of the otolithic organ

    Energy Technology Data Exchange (ETDEWEB)

    Okuno, T.; Nomura, Y.; Young, Y.H.; Hara, M. (Univ. of Tokyo (Japan))

    1990-12-01

    An argon laser was used to irradiate the otolithic organs of guinea pigs and cynomolgus monkeys. After stapedectomy, the argon laser (1.5 W x 0.5 sec/shot) irradiated the utricle or saccule without touching the sensory organs. The stapes was replaced over the oval window after irradiation. The animals used for acute observation were killed immediately for morphologic studies; those used for long-term observation were kept alive for 2, 4, or 10 weeks. Acute observation revealed that sensory and supporting cells were elevated from the basement membrane only in the irradiated area. No rupture of the membranous labyrinth was observed. Long-term observation revealed that the otolith of the macula utriculi had disappeared in 2-week specimens. The entire macula utricili had disappeared in 10-week specimens. No morphologic changes were observed in cochlea, semicircular canals, or membranous labyrinth. The saccule showed similar changes.

  19. Integrin alpha 10, CD44, PTEN, cadherin-11 and lactoferrin expressions are potential biomarkers for selecting patients in need of central nervous system prophylaxis in diffuse large B-cell lymphoma.

    Science.gov (United States)

    Lemma, Siria A; Kuusisto, Milla; Haapasaari, Kirsi-Maria; Sormunen, Raija; Lehtinen, Tuula; Klaavuniemi, Tuula; Eray, Mine; Jantunen, Esa; Soini, Ylermi; Vasala, Kaija; Böhm, Jan; Salokorpi, Niina; Koivunen, Petri; Karihtala, Peeter; Vuoristo, Jussi; Turpeenniemi-Hujanen, Taina; Kuittinen, Outi

    2017-08-01

    Central nervous system (CNS) relapse is a devastating complication that occurs in about 5% of diffuse large B-cell lymphoma (DLBCL) patients. Currently, there are no predictive biological markers. We wanted to study potential biomarkers of CNS tropism that play a role in adhesion, migration and/or in the regulation of inflammatory responses. The expression levels of ITGA10, CD44, PTEN, cadherin-11, CDH12, N-cadherin, P-cadherin, lactoferrin and E-cadherin were studied with IHC and IEM. GEP was performed to see whether found expressional changes are regulated at DNA/RNA level. IHC included 96 samples of primary CNS lymphoma (PCNSL), secondary CNS lymphoma (sCNSL) and systemic DLBCL (sDLBCL). IEM included two PCNSL, one sCNSL, one sDLBCL and one reactive lymph node samples. GEP was performed on two DLBCL samples, one with and one without CNS relapse. CNS disease was associated with enhanced expression of cytoplasmic and membranous ITGA10 and nuclear PTEN (P lactoferrin expression was upregulated (P lactoferrin and E-cadherin were under-expressed in CNS disease. Our results are in line with previous studies, where gene expressions in extracellular matrix and adhesion-related pathways are altered in CNS lymphoma. This study gives new information on the DLBCL CNS tropism. If further verified, these markers might become useful in predicting CNS relapses. © The Author 2017. Published by Oxford University Press.

  20. The thermoluminescence of carp otoliths: A fingerprint in ...

    African Journals Online (AJOL)

    This paper reports a pilot study on the thermoluminescence (TL) of carbonate minerals of carp otoliths from the heavily polluted Baiyangdian Lake (BYD) in Hebei Province and non-polluted Miyun Water Reservoir (MY) in Beijing Municipality of China. Analyses on trace elements of otoliths and water show that the heavy ...

  1. Architecture of the Otolith End Organ: With Some Functional Considerations,

    Science.gov (United States)

    structure in histological slides is uncertain. An attempt was made to preserve the otolithic architecture as naturally as possible. In studying squirrel...monkey temporal bones the results obtained with three different decalcifiers are compared. The best architectural preservation of the otolithic end

  2. Otoliths versus scales: evaluating the most suitable structure for ...

    African Journals Online (AJOL)

    Otoliths (1.4% rejected) were more readable than scales (41.7% and 7.5% rejected) for Wriggleswade and Mankazana Impoundments respectively. Otolith readings were more precise (average percentage error (APE) = 13.6%; coefficient of variation (CV) = 15.8%) than scales (APE = 18.0%; CV = 21.9%) for the total sample ...

  3. Enrichment of Pb, Hg and Cr in cultured carp otolith

    African Journals Online (AJOL)

    AJL

    2012-01-26

    Jan 26, 2012 ... Fish otolith is a good recorder of water environment in which the fish lived. In order to identify the elements in otolith that are sensitive to environment and their enrichment rules, lab-culture experiments of carps were carried out. Pb, Hg and Cr were added separately into tanks in which the carps lived, and.

  4. Otolith tethering in the zebrafish otic vesicle requires Otogelin and ?-Tectorin

    OpenAIRE

    Stooke-Vaughan, Georgina A.; Obholzer, Nikolaus D.; Baxendale, Sarah; Megason, Sean G.; Whitfield, Tanya T.

    2015-01-01

    Otoliths are biomineralised structures important for balance and hearing in fish. Their counterparts in the mammalian inner ear, otoconia, have a primarily vestibular function. Otoliths and otoconia form over sensory maculae and are attached to the otolithic membrane, a gelatinous extracellular matrix that provides a physical coupling between the otolith and the underlying sensory epithelium. In this study, we have identified two proteins required for otolith tethering in the zebrafish ear, a...

  5. Otolith tethering in the zebrafish otic vesicle requires Otogelin and alpha-Tectorin

    OpenAIRE

    Stooke-Vaughan, G.A.; Obholzer, N.D.; Baxendale, S.; Megason, S.G.; Whitfield, T.T.

    2015-01-01

    Otoliths are biomineralised structures important for balance and hearing in fish. Their counterparts in the mammalian inner ear, otoconia, have a primarily vestibular function. Otoliths and otoconia form over sensory maculae and are attached to the otolithic membrane, a gelatinous extracellular matrix that provides a physical coupling between the otolith and the underlying sensory epithelium. In this study, we have identified two proteins required for otolith tethering in the zebrafish ear, a...

  6. Suitability of otolith microchemistry for stock separation of Baltic cod

    DEFF Research Database (Denmark)

    Heidemann, F; Marohn, L; Hinrichsen, HH

    2012-01-01

    Microchemical otolith analyses have been shown to provide valuable information on the life history, dispersal and stock characteristics of teleost fish. In the present study, the suitability of this technique for identifying the origin and distribution of Atlantic cod Gadus morhua L. from...... origins led to spawning-site specific element concentrations in otolith cores. The results indicate that microchemical analyses of Baltic cod otoliths are applicable for differentiating individuals of different stocks. Analyses of similarities including 12 element/calcium ratios resulted in significant......, however, was not possible. Elemental compositions from the core regions of otoliths from young of the year cod caught in eastern and western Baltic Sea spawning grounds showed significant differences in Sr/Ca, Ba/Ca and Mg/Ca concentrations. Analyses of similarities again showed significant differences...

  7. Crystal phases of calcium carbonate within otoliths of Cyprinus ...

    African Journals Online (AJOL)

    Yomi

    2012-04-26

    Campana and Neilson., 1985). Plenty of information recorded in otoliths have been studied to resolve fish ecological questions such as fish age, feeding and growth history, recruitment and migration, mortality and stock structure, ...

  8. Shedding light on fish otolith biomineralization using a bioenergetic approach.

    Directory of Open Access Journals (Sweden)

    Ronan Fablet

    Full Text Available Otoliths are biocalcified bodies connected to the sensory system in the inner ears of fish. Their layered, biorhythm-following formation provides individual records of the age, the individual history and the natural environment of extinct and living fish species. Such data are critical for ecosystem and fisheries monitoring. They however often lack validation and the poor understanding of biomineralization mechanisms has led to striking examples of misinterpretations and subsequent erroneous conclusions in fish ecology and fisheries management. Here we develop and validate a numerical model of otolith biomineralization. Based on a general bioenergetic theory, it disentangles the complex interplay between metabolic and temperature effects on biomineralization. This model resolves controversial issues and explains poorly understood observations of otolith formation. It represents a unique simulation tool to improve otolith interpretation and applications, and, beyond, to address the effects of both climate change and ocean acidification on other biomineralizing organisms such as corals and bivalves.

  9. Lead-Radium Activity Ratios From Otoliths of Regional Bottomfishes

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data set contains lead-radium dating of opakapaka (Pristipomoides filamentosus) otoliths from recent and archival collections (1987-2009).

  10. Shedding light on fish otolith biomineralization using a bioenergetic approach.

    Science.gov (United States)

    Fablet, Ronan; Pecquerie, Laure; de Pontual, Hélène; Høie, Hans; Millner, Richard; Mosegaard, Henrik; Kooijman, Sebastiaan A L M

    2011-01-01

    Otoliths are biocalcified bodies connected to the sensory system in the inner ears of fish. Their layered, biorhythm-following formation provides individual records of the age, the individual history and the natural environment of extinct and living fish species. Such data are critical for ecosystem and fisheries monitoring. They however often lack validation and the poor understanding of biomineralization mechanisms has led to striking examples of misinterpretations and subsequent erroneous conclusions in fish ecology and fisheries management. Here we develop and validate a numerical model of otolith biomineralization. Based on a general bioenergetic theory, it disentangles the complex interplay between metabolic and temperature effects on biomineralization. This model resolves controversial issues and explains poorly understood observations of otolith formation. It represents a unique simulation tool to improve otolith interpretation and applications, and, beyond, to address the effects of both climate change and ocean acidification on other biomineralizing organisms such as corals and bivalves.

  11. ARE ELEMENTAL FINGERPRINTS OF FISH OTOLITHS DISTINCT AMONG GREAT LAKES COASTAL NURSERY AREAS?

    Science.gov (United States)

    Elemental composition of an otolith reflects a fish's rearing environment, so otolith geochemistry can record differences in ambient water conditions specific to habitats used during a fish's life history. Although few studies have been conducted in freshwater, trace ...

  12. Effectiveness of Otolith Repositioning Maneuvers and Vestibular Rehabilitation exercises in elderly people with Benign Paroxysmal Positional Vertigo: a systematic review.

    Science.gov (United States)

    Ribeiro, Karyna Figueiredo; Oliveira, Bruna Steffeni; Freitas, Raysa V; Ferreira, Lidiane M; Deshpande, Nandini; Guerra, Ricardo O

    2017-06-29

    Benign Paroxysmal Positional Vertigo is highly prevalent in elderly people. This condition is related to vertigo, hearing loss, tinnitus, poor balance, gait disturbance, and an increase in risk of falls, leading to postural changes and quality of life decreasing. To evaluate the outcomes obtained by clinical trials on the effectiveness of Otolith Repositioning Maneuver and Vestibular Rehabilitation exercises in the treatment of Benign Paroxysmal Positional Vertigo in elderly. The literature research was performed using PubMed, Scopus, Web of Science and PEDro databases, and included randomized controlled clinical trials in English, Spanish and Portuguese, published during January 2000 to August 2016. The methodological quality of the studies was assessed by PEDro score and the outcomes analysis was done by critical revision of content. Six studies were fully reviewed. The average age of participants ranged between 67.2 and 74.5 years. The articles were classified from 2 to 7/10 through the PEDro score. The main outcome measures analyzed were vertigo, positional nystagmus and postural balance. Additionally, the number of maneuvers necessary for remission of the symptoms, the quality of life, and the functionality were also assessed. The majority of the clinical trials used Otolith Repositioning Maneuver (n=5) and 3 articles performed Vestibular Rehabilitation exercises in addition to Otolith Repositioning Maneuver or pharmacotherapy. One study showed that the addition of movement restrictions after maneuver did not influence the outcomes. There was a trend of improvement in Benign Paroxysmal Positional Vertigo symptomatology in elderly patients who underwent Otolith Repositioning Maneuver. There is sparse evidence from methodologically robust clinical trials that examined the effects of Otolith Repositioning Maneuver and Vestibular Rehabilitation exercises for treating Benign Paroxysmal Positional Vertigo in the elderly. Randomized controlled clinical trials with

  13. Bisphenol A induces otolith malformations during vertebrate embryogenesis

    Directory of Open Access Journals (Sweden)

    Demeneix Barbara

    2011-01-01

    Full Text Available Abstract Background The plastic monomer and plasticizer bisphenol A (BPA, used for manufacturing polycarbonate plastic and epoxy resins, is produced at over 2.5 million metric tons per year. Concerns have been raised that BPA acts as an endocrine disruptor on both developmental and reproductive processes and a large body of evidence suggests that BPA interferes with estrogen and thyroid hormone signaling. Here, we investigated BPA effects during embryonic development using the zebrafish and Xenopus models. Results We report that BPA exposure leads to severe malformations of the otic vesicle. In zebrafish and in Xenopus embryos, exposure to BPA during the first developmental day resulted in dose-dependent defects in otolith formation. Defects included aggregation, multiplication and occasionally failure to form otoliths. As no effects on otolith development were seen with exposure to micromolar concentrations of thyroid hormone, 17-ß-estradiol or of the estrogen receptor antagonist ICI 182,780 we conclude that the effects of BPA are independent of estrogen receptors or thyroid-hormone receptors. Na+/K+ ATPases are crucial for otolith formation in zebrafish. Pharmacological inhibition of the major Na+/K+ ATPase with ouabain can rescue the BPA-induced otolith phenotype. Conclusions The data suggest that the spectrum of BPA action is wider than previously expected and argue for a systematic survey of the developmental effects of this endocrine disruptor.

  14. A review of otolith pathways to brainstem and cerebellum.

    Science.gov (United States)

    Büttner-Ennever, J A

    1999-05-28

    Our knowledge of otolith pathways is developing rapidly, but is still far from complete. Primary afferents from the sacculus and utricle terminate mainly in the lateral, inferior and caudal superior vestibular nuclei, and the ventral cerebellum, in particular the nodulus. Otolith signals descend via reticulo- and vestibulospinal pathways in the spinal cord to influence neck motoneurons and ascending proprioceptive afferents. Utricular information can reach the extraocular eye muscles via mono-, di-, and multisynaptic pathways, but saccular afferents probably only by multisynaptic pathways. The otolith signals are relayed from the vestibular nuclei, medullary reticular formation, inferior olive, and lateral reticular nucleus to sagittal zones in the caudal cerebellar vermis (nodulus and uvula), and influence the deep cerebellar nuclei. The graviceptive information could be channeled by the cerebellar efferents back to the vestibular and inferior olive complex, or fed into ascending pathways that would innervate the mescencephalon, the thalamus, and cerebral cortex.

  15. Assessment of D-methionine protecting cisplatin-induced otolith toxicity by vestibular-evoked myogenic potential tests, ATPase activities and oxidative state in guinea pigs.

    Science.gov (United States)

    Lo, Wu-Chia; Chang, Chih-Ming; Liao, Li-Jen; Wang, Chi-Te; Young, Yi-Ho; Chang, Yih-Leong; Cheng, Po-Wen

    2015-01-01

    To date, inadequate study has been devoted to the toxic vestibular effects caused by cisplatin. In addition, no electrophysiological examination has been conducted to assess cisplatin-induced otolith toxicity. The purposes of this study are thus two-fold: 1) to determine whether cervical vestibular-evoked myogenic potentials (VEMPs) and ocular VEMPs are practical electrophysiological methods of testing for cisplatin-induced otolith toxicity and 2) to examine if D-methionine (D-met) pre-injection would protect the otolith organs against cisplatin-induced changes in enzyme activities and/or oxidative status. Guinea pigs were intraperitoneally treated once daily with the following injections for seven consecutive days: sterile 0.9% saline control, cisplatin (5 mg/kg) only, D-met (300 mg/kg) only, or a combination of d-met (300 mg/kg) and cisplatin (5 mg/kg), respectively, with a 30 minute window in between. Each animal underwent the oVEMP and cVEMP tests before and after treatment. The changes in the biochemistry of the otolith organs, including membranous Na(+), K(+)-ATPase and Ca(2+)-ATPase, lipid peroxidation (LPO) levels and nitric oxide (NO) levels, were also evaluated. In the cisplatin-only treated guinea pigs, the mean amplitudes of the oVEMP tests were significantly (poxidative stress induced by cisplatin toxicity in the otolith organs. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Within-otolith variability in chemical fingerprints: implications for sampling designs and possible environmental interpretation.

    Science.gov (United States)

    Di Franco, Antonio; Bulleri, Fabio; Pennetta, Antonio; De Benedetto, Giuseppe; Clarke, K Robert; Guidetti, Paolo

    2014-01-01

    Largely used as a natural biological tag in studies of dispersal/connectivity of fish, otolith elemental fingerprinting is usually analyzed by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS). LA-ICP-MS produces an elemental fingerprint at a discrete time-point in the life of a fish and can generate data on within-otolith variability of that fingerprint. The presence of within-otolith variability has been previously acknowledged but not incorporated into experimental designs on the presumed, but untested, grounds of both its negligibility compared to among-otolith variability and of spatial autocorrelation among multiple ablations within an otolith. Here, using a hierarchical sampling design of spatial variation at multiple scales in otolith chemical fingerprints for two Mediterranean coastal fishes, we explore: 1) whether multiple ablations within an otolith can be used as independent replicates for significance tests among otoliths, and 2) the implications of incorporating within-otolith variability when assessing spatial variability in otolith chemistry at a hierarchy of spatial scales (different fish, from different sites, at different locations on the Apulian Adriatic coast). We find that multiple ablations along the same daily rings do not necessarily exhibit spatial dependency within the otolith and can be used to estimate residual variability in a hierarchical sampling design. Inclusion of within-otolith measurements reveals that individuals at the same site can show significant variability in elemental uptake. Within-otolith variability examined across the spatial hierarchy identifies differences between the two fish species investigated, and this finding leads to discussion of the potential for within-otolith variability to be used as a marker for fish exposure to stressful conditions. We also demonstrate that a 'cost'-optimal allocation of sampling effort should typically include some level of within-otolith replication in the

  17. The cerebellar nodulus/uvula integrates otolith signals for the translational vestibulo-ocular reflex.

    Directory of Open Access Journals (Sweden)

    Mark F Walker

    2010-11-01

    Full Text Available The otolith-driven translational vestibulo-ocular reflex (tVOR generates compensatory eye movements to linear head accelerations. Studies in humans indicate that the cerebellum plays a critical role in the neural control of the tVOR, but little is known about mechanisms of this control or the functions of specific cerebellar structures. Here, we chose to investigate the contribution of the nodulus and uvula, which have been shown by prior studies to be involved in the processing of otolith signals in other contexts.We recorded eye movements in two rhesus monkeys during steps of linear motion along the interaural axis before and after surgical lesions of the cerebellar uvula and nodulus. The lesions strikingly reduced eye velocity during constant-velocity motion but had only a small effect on the response to initial head acceleration. We fit eye velocity to a linear combination of head acceleration and velocity and to a dynamic mathematical model of the tVOR that incorporated a specific integrator of head acceleration. Based on parameter optimization, the lesion decreased the gain of the pathway containing this new integrator by 62%. The component of eye velocity that depended directly on head acceleration changed little (gain decrease of 13%. In a final set of simulations, we compared our data to the predictions of previous models of the tVOR, none of which could account for our experimental findings.Our results provide new and important information regarding the neural control of the tVOR. Specifically, they point to a key role for the cerebellar nodulus and uvula in the mathematical integration of afferent linear head acceleration signals. This function is likely to be critical not only for the tVOR but also for the otolith-mediated reflexes that control posture and balance.

  18. Effect of ocean acidification on growth and otolith condition of juvenile scup, Stenotomus chrysops.

    Science.gov (United States)

    Perry, Dean M; Redman, Dylan H; Widman, James C; Meseck, Shannon; King, Andrew; Pereira, Jose J

    2015-09-01

    Increasing amounts of atmospheric carbon dioxide (CO2) from human industrial activities are causing changes in global ocean carbonate chemistry, resulting in a reduction in pH, a process termed "ocean acidification." It is important to determine which species are sensitive to elevated levels of CO2 because of potential impacts to ecosystems, marine resources, biodiversity, food webs, populations, and effects on economies. Previous studies with marine fish have documented that exposure to elevated levels of CO2 caused increased growth and larger otoliths in some species. This study was conducted to determine whether the elevated partial pressure of CO2 (pCO2) would have an effect on growth, otolith (ear bone) condition, survival, or the skeleton of juvenile scup, Stenotomus chrysops, a species that supports both important commercial and recreational fisheries. Elevated levels of pCO2 (1200-2600 μatm) had no statistically significant effect on growth, survival, or otolith condition after 8 weeks of rearing. Field data show that in Long Island Sound, where scup spawn, in situ levels of pCO2 are already at levels ranging from 689 to 1828 μatm due to primary productivity, microbial activity, and anthropogenic inputs. These results demonstrate that ocean acidification is not likely to cause adverse effects on the growth and survivability of every species of marine fish. X-ray analysis of the fish revealed a slightly higher incidence of hyperossification in the vertebrae of a few scup from the highest treatments compared to fish from the control treatments. Our results show that juvenile scup are tolerant to increases in seawater pCO2, possibly due to conditions this species encounters in their naturally variable environment and their well-developed pH control mechanisms.

  19. The genetic mineralogical characteristics of fish otoliths and their ...

    African Journals Online (AJOL)

    ... fish and the variation of the ocean environment, in order to predict the environmental variation trend of related waters and make strategic plan for fishery production. Thermoluminescence technique can be taken as a new tool in the investigation of fish otolith to describe the heavy metal pollution of related waters, and the ...

  20. Validation of daily increments periodicity in otoliths of spotted gar

    Science.gov (United States)

    Snow, Richard A.; Long, James M.; Frenette, Bryan D.

    2017-01-01

    Accurate age and growth information is essential in successful management of fish populations and for understanding early life history. We validated daily increment deposition, including the timing of first ring formation, for spotted gar (Lepisosteus oculatus) through 127 days post hatch. Fry were produced from hatchery-spawned specimens, and up to 10 individuals per week were sacrificed and their otoliths (sagitta, lapillus, and asteriscus) removed for daily age estimation. Daily age estimates for all three otolith pairs were significantly related to known age. The strongest relationships existed for measurements from the sagitta (r2 = 0.98) and the lapillus (r2 = 0.99) with asteriscus (r2 = 0.95) the lowest. All age prediction models resulted in a slope near unity, indicating that ring deposition occurred approximately daily. Initiation of ring formation varied among otolith types, with deposition beginning 3, 7, and 9 days for the sagitta, lapillus, and asteriscus, respectively. Results of this study suggested that otoliths are useful to estimate daily age of spotted gar juveniles; these data may be used to back calculate hatch dates, estimate early growth rates, and correlate with environmental factor that influence spawning in wild populations. is early life history information will be valuable in better understanding the ecology of this species. 

  1. Relationship of phosphorus content in carp otoliths with that in ...

    African Journals Online (AJOL)

    It has been of high concern that the phosphorus pollution is getting serious after lake eutrophication in the Taihu Lake, the third largest freshwater lake in China. As a sensitive recorder of the ambient water and fish exposures, fish otolith has been studied as a potential dynamic monitor of water quality by many biologists and ...

  2. Precision of two methods for estimating age from burbot otoliths

    Science.gov (United States)

    Edwards, W.H.; Stapanian, M.A.; Stoneman, A.T.

    2011-01-01

    Lower reproductive success and older age structure are associated with many burbot (Lota lota L.) populations that are declining or of conservation concern. Therefore, reliable methods for estimating the age of burbot are critical for effective assessment and management. In Lake Erie, burbot populations have declined in recent years due to the combined effects of an aging population (&xmacr; = 10 years in 2007) and extremely low recruitment since 2002. We examined otoliths from burbot (N = 91) collected in Lake Erie in 2007 and compared the estimates of burbot age by two agers, each using two established methods (cracked-and-burned and thin-section) of estimating ages from burbot otoliths. One ager was experienced at estimating age from otoliths, the other was a novice. Agreement (precision) between the two agers was higher for the thin-section method, particularly at ages 6–11 years, based on linear regression analyses and 95% confidence intervals. As expected, precision between the two methods was higher for the more experienced ager. Both agers reported that the thin sections offered clearer views of the annuli, particularly near the margins on otoliths from burbot ages ≥8. Slides for the thin sections required some costly equipment and more than 2 days to prepare. In contrast, preparing the cracked-and-burned samples was comparatively inexpensive and quick. We suggest use of the thin-section method for estimating the age structure of older burbot populations.

  3. Thermoluminescence (TL) analysis for otoliths of the wild carps ...

    African Journals Online (AJOL)

    TL characteristics of otoliths from the wild carps (cyprinoid) living in the Baiyangdian Lake, Hebei Province and Miyun Reservoir, Beijing City was first studied, and ... contaminated water, and this could be regarded as an important typomorphic biomineral for monitoring the contaminative degree and environment change of ...

  4. Mineralogical and geochemical study of carp otoliths from ...

    African Journals Online (AJOL)

    enoh

    2012-03-29

    Mar 29, 2012 ... Recent developments in fish otolith research. Columbia: University of South Carolina Press. Spann N, Harper EM, Aldridge DC (2010). The unusual mineral vaterite in shells of the freshwater bivalve Corbicula fluminea from the UK. Naturwissenschaften, 97: 743-751. Strong MB, Neilson JD, Hunt JJ (1986).

  5. Otolith geochemistry does not reflect dispersal history of clownfish larvae

    KAUST Repository

    Berumen, Michael L.

    2010-07-01

    Natural geochemical signatures in calcified structures are commonly employed to retrospectively estimate dispersal pathways of larval fish and invertebrates. However, the accuracy of the approach is generally untested due to the absence of individuals with known dispersal histories. We used genetic parentage analysis (genotyping) to divide 110 new recruits of the orange clownfish, Amphiprion percula, from Kimbe Island, Papua New Guinea, into two groups: "self-recruiters" spawned by parents on Kimbe Island and "immigrants" that had dispersed from distant reefs (>10 km away). Analysis of daily increments in sagittal otoliths found no significant difference in PLDs or otolith growth rates between self-recruiting and immigrant larvae. We also quantified otolith Sr/Ca and Ba/Ca ratios during the larval phase using laser ablation inductively coupled plasma mass spectrometry. Again, we found no significant differences in larval profiles of either element between self-recruits and immigrants. Our results highlight the need for caution when interpreting otolith dispersal histories based on natural geochemical tags in the absence of water chemistry data or known-origin larvae with which to test the discriminatory ability of natural tags. © 2010 Springer-Verlag.

  6. A review on otolith models in human perception.

    Science.gov (United States)

    Asadi, Houshyar; Mohamed, Shady; Lim, Chee Peng; Nahavandi, Saeid

    2016-08-01

    The vestibular system, which consists of semicircular canals and otolith, are the main sensors mammals use to perceive rotational and linear motions. Identifying the most suitable and consistent mathematical model of the vestibular system is important for research related to driving perception. An appropriate vestibular model is essential for implementation of the Motion Cueing Algorithm (MCA) for motion simulation purposes, because the quality of the MCA is directly dependent on the vestibular model used. In this review, the history and development process of otolith models are presented and analyzed. The otolith organs can detect linear acceleration and transmit information about sensed applied specific forces on the human body. The main purpose of this review is to determine the appropriate otolith models that agree with theoretical analyses and experimental results as well as provide reliable estimation for the vestibular system functions. Formulating and selecting the most appropriate mathematical model of the vestibular system is important to ensure successful human perception modelling and simulation when implementing the model into the MCA for motion analysis. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Shedding light on fish otolith biomineralisation using a bioenergetic approach

    NARCIS (Netherlands)

    Fablet, R.; Pecquerie, L; Pontual, H.D.; Hoie, H.; Millner, R.; Mosegaard, H.; Kooijman, S.A.L.M.

    2011-01-01

    Otoliths are biocalcified bodies connected to the sensory system in the inner ears of fish. Their layered, biorhythm-following formation provides individual records of the age, the individual history and the natural environment of extinct and living fish species. Such data are critical for ecosystem

  8. Effect of textile factory effluent on otolith and somatic growth ...

    African Journals Online (AJOL)

    Are otolith parameters more sensitive than somatic indices in detecting stress conditions in fish? This question was investigated using juvenile-sized Clarias gariepinus in a 30-day exposure bioassay to a textile factory effluent. A series of static bioassays were initially conducted with concentrations of 0.00-40.00% and the ...

  9. Otoliths as an integral part in fossil fish taxonomy

    Directory of Open Access Journals (Sweden)

    Christoph Gierl

    2015-11-01

    Full Text Available Otoliths are small structures in the skull of fishes. They are responsible for hearing and orientation in the 3-dimensional space. They also hold valuable information regarding the taxonomy. Their outline, the shape of the sulcus and other features allow the determination of a fish even to the species level. A lot of fossil species are solely based on otoliths because of their good chance of preservation. Gobies are in this case no different. An additional challenge in gobies is their high similarity between species concerning the preservable parts. Fossil skeletons that are 20 Million years old can show only few differences compared to recent gobies. These features are often hardly recognizable due to their preservation. As a consequence many fossil gobies have been assigned to the genus Gobius sensu lato. Examples are two gobies from the Miocene of Southern Germany. They have a unique combination of characters (six branchiostegals, palatine resembling a “T”, no entopterygoid that allows the rectification of a new fossil genus but the two species are hardly distinguishable based only on the skeleton. The key hints in having two species are the otoliths. They show slight but consistent differences in their outline. This shows that otoliths can be a key feature in species identification. They should also be taken into consideration by recent fish species. Not to mention their possible phylogenetic potential that remains to be explored.

  10. Shedding light on fish otolith biomineralization using a bioenergetic approach

    DEFF Research Database (Denmark)

    Fablet, R.; Pecquerie, L.; de Pontual, H.

    2011-01-01

    Otoliths are biocalcified bodies connected to the sensory system in the inner ears of fish. Their layered, biorhythm-following formation provides individual records of the age, the individual history and the natural environment of extinct and living fish species. Such data are critical for ecosys...... simulation tool to improve otolith interpretation and applications, and, beyond, to address the effects of both climate change and ocean acidification on other biomineralizing organisms such as corals and bivalves...... for ecosystem and fisheries monitoring. They however often lack validation and the poor understanding of biomineralization mechanisms has led to striking examples of misinterpretations and subsequent erroneous conclusions in fish ecology and fisheries management. Here we develop and validate a numerical model...

  11. Shedding Light on Fish Otolith Biomineralization Using a Bioenergetic Approach

    OpenAIRE

    FABLET, Ronan; Pecquerie, Laure; PONTUAL DE, Hélène; Høie, Hans; Millner, Richard; Mosegaard, Henrik; Kooijman, Sebastiaan A. L. M.

    2011-01-01

    Otoliths are biocalcified bodies connected to the sensory system in the inner ears of fish. Their layered, biorhythm-following formation provides individual records of the age, the individual history and the natural environment of extinct and living fish species. Such data are critical for ecosystem and fisheries monitoring. They however often lack validation and the poor understanding of biomineralization mechanisms has led to striking examples of misinterpretations and subsequent erroneous ...

  12. Shedding light on fish otolith biomineralization using a bioenergetic approach

    OpenAIRE

    Fablet, R.; Pecquerie, L.; Pontual, H. de; Høie, H.; Millner, R.; Mosegaard, Henrik; Sebastiaan, A.; Kooijman, S. A. L. M.

    2011-01-01

    Otoliths are biocalcified bodies connected to the sensory system in the inner ears of fish. Their layered, biorhythm-following formation provides individual records of the age, the individual history and the natural environment of extinct and living fish species. Such data are critical for ecosystem and fisheries monitoring. They however often lack validation and the poor understanding of biomineralization mechanisms has led to striking examples of misinterpretations and subsequent erroneous ...

  13. The interaction of otolith organ stimulation and smooth pursuit tracking.

    Science.gov (United States)

    Shelhamer, M; Young, L R

    1994-01-01

    The interaction of otolith organ stimulation and horizontal pursuit eye tracking in humans was studied in two different paradigms. In the first we measured the effects of lateral linear acceleration on ocular tracking of a retinal after-image, as compared to eye movements produced by acceleration alone (the linear VOR). The second paradigm determined the improvement in smooth oculomotor tracking presumably due to otolith input, by comparing tracking of an earth-fixed target during subject motion to tracking of target motion with the subject stationary. Subject and target motions in each case were sinusoidal. After-image tracking enhanced the gain of the linear VOR by a factor of 2 to 10. This is interpreted to mean that oculomotor efferent copy information is used to reconstruct an internal representation of target velocity, which is then tracked by the oculomotor system in the after-image condition. In the second paradigm, linear motion information transduced by the otolith organs combined with visual target information to yield improved oculomotor tracking over either system alone.

  14. Otolith marking of juvenile shortnose gar by immersion in oxytetracycline

    Science.gov (United States)

    Snow, Richard A.; Long, James M.

    2017-01-01

    Oxytetracycline (OTC) has been used to mark a variety of fish species at multiple developmental stages; however, there is little information on batch-marking Lepisosteidae. Juvenile Shortnose Gar Lepisosteus platostomus (53 ± 3 mm TL) were seined from an Oklahoma State University research pond and transported to the Oklahoma Fishery Research Lab. Juvenile Shortnose Gar were exposed to a range of OTC concentrations—0, 500, 600, and 700 mg/L—for 4, 5, or 6 h. Lapillus and sagitta otoliths were examined 14 d postexposure for mark presence and evaluation using fluorescent microscopy. Overall, 93.3% of otoliths exposed to OTC exhibited a mark. Concentration of OTC affected the mean mark quality, whereas duration and otolith type examined did not. However, as concentration increased, so did mortality, suggesting a balance is needed to achieve marking goals. Based on our findings, batch marking of Shortnose Gar can be successful at OTC concentrations from 500 to 700 mg/L for 4–6 h, although mark quality may vary and mortality rates increase at the higher concentrations and longer durations.

  15. Clinical features of otolith organ-specific vestibular dysfunction.

    Science.gov (United States)

    Fujimoto, Chisato; Suzuki, Sayaka; Kinoshita, Makoto; Egami, Naoya; Sugasawa, Keiko; Iwasaki, Shinichi

    2018-01-01

    To elucidate the clinical features and vestibular symptoms of patients with otolith organ dysfunction in the presence of normal function of the semicircular canals. We reviewed the clinical records of 277 consecutive new patients with balance disorders who underwent testing of cervical and ocular vestibular evoked myogenic potentials (cVEMPs and oVEMPs) as well as caloric testing and video head impulse testing (vHIT). We identified 76 patients who showed normal caloric responses and normal vHIT findings in each SCC plane, but abnormal responses in cVEMP and/or oVEMP testing. Benign paroxysmal positional vertigo (BPPV) was the most common diagnosis. 37% of patients could not be categorized into any of the established clinical entities that could cause a balance disorder and did not show sensorineural hearing loss. The most common clinical manifestation in the idiopathic cases was recurrent rotatory vertigo with a duration of 1-12 h. The most common diagnosis of otolith organ-specific vestibular dysfunction was BPPV. The most common clinical manifestation in the idiopathic cases was recurrent rotatory vertigo. Specific dysfunction of the otolith organs occurs in association with some of the undiagnosed patients with recurrent rotatory vertigo. Copyright © 2017 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

  16. Within-otolith variability in chemical fingerprints: implications for sampling designs and possible environmental interpretation.

    Directory of Open Access Journals (Sweden)

    Antonio Di Franco

    Full Text Available Largely used as a natural biological tag in studies of dispersal/connectivity of fish, otolith elemental fingerprinting is usually analyzed by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS. LA-ICP-MS produces an elemental fingerprint at a discrete time-point in the life of a fish and can generate data on within-otolith variability of that fingerprint. The presence of within-otolith variability has been previously acknowledged but not incorporated into experimental designs on the presumed, but untested, grounds of both its negligibility compared to among-otolith variability and of spatial autocorrelation among multiple ablations within an otolith. Here, using a hierarchical sampling design of spatial variation at multiple scales in otolith chemical fingerprints for two Mediterranean coastal fishes, we explore: 1 whether multiple ablations within an otolith can be used as independent replicates for significance tests among otoliths, and 2 the implications of incorporating within-otolith variability when assessing spatial variability in otolith chemistry at a hierarchy of spatial scales (different fish, from different sites, at different locations on the Apulian Adriatic coast. We find that multiple ablations along the same daily rings do not necessarily exhibit spatial dependency within the otolith and can be used to estimate residual variability in a hierarchical sampling design. Inclusion of within-otolith measurements reveals that individuals at the same site can show significant variability in elemental uptake. Within-otolith variability examined across the spatial hierarchy identifies differences between the two fish species investigated, and this finding leads to discussion of the potential for within-otolith variability to be used as a marker for fish exposure to stressful conditions. We also demonstrate that a 'cost'-optimal allocation of sampling effort should typically include some level of within-otolith

  17. Provenancing fish in freshwaters of the Alpine Foreland using Sr/Ca and 87Sr/86Sr ratios in otoliths and otolith shape parameters

    Directory of Open Access Journals (Sweden)

    Johannes Oehm

    2015-12-01

    Although the studied freshwaters were located only in a 50 km range around lake Chiemsee on a similar geological background, differences in water chemistry, fish otolith chemistry and shape were identified. Species specific differences in reflection of the Sr/Ca ratio of a specific water body were detected. Microchemical and morphological otoliths analyses complemented each other and allowed assigning fish to specific groups of waters of origin. This information provides an important basis for the further application of otolith chemistry and shape analysis in the Alpine foreland for a diverse range of ecological questions.

  18. Assessment of errors in cetacean diet analysis : in vitro digestion of otoliths

    NARCIS (Netherlands)

    Wijnsma, G; Pierce, GJ; Santos, MB

    Research into the feeding habits of cetaceans has traditionally relied on examining samples taken From the digestive tracts of commercially caught or stranded and by-caught animals. This depends on the identification and measurement of hard parts such as fish otoliths. Otoliths are often partially

  19. Nitrogen isotopic analysis of carbonate-bound organic matter in modern and fossil fish otoliths

    Science.gov (United States)

    Lueders-Dumont, Jessica A.; Wang, Xingchen T.; Jensen, Olaf P.; Sigman, Daniel M.; Ward, Bess B.

    2018-03-01

    The nitrogen isotopic composition (δ15N) of otolith-bound organic matter (OM) is a potential source of information on dietary history of bony fishes. In contrast to the δ15N of white muscle tissue, the most commonly used tissue for ecological studies, the δ15N of otolith-bound OM (δ15Noto) provides a record of whole life history. More importantly, δ15Noto can be measured in contexts where tissue is not available, for example, in otolith archives and sedimentary deposits. The utility and robustness of otolith δ15N analysis was heretofore limited by the low N content of otoliths, which precluded the routine measurement of individual otoliths as well as the thorough cleaning of otolith material prior to analysis. Here, we introduce a new method based on oxidation to nitrate followed by bacterial conversion to N2O. The method requires 200-fold less N compared to traditional combustion approaches, allowing for thorough pre-cleaning and replicated analysis of individual otoliths of nearly any size. Long term precision of δ15Noto is 0.3‰. Using an internal standard of Atlantic cod (Gadus morhua) otoliths, we examine the parameters of the oxidative cleaning step with regard to oxidant (potassium persulfate and sodium hypochlorite), temperature, and time. We also report initial results that verify the usefulness of δ15Noto for ecological studies. For three salmonid species, left and right otoliths from the same fish are indistinguishable. We find that the δ15Noto of pink salmon (Oncorhynchus gorbuscha) is related to the size of the fish for this species. We find that intra-cohort δ15Noto standard deviation for wild pink salmon, farmed brown trout (Salmo trutta), and farmed rainbow trout (Oncorhynchus mykiss) are all 0.4‰ or less, suggesting that δ15Noto will be valuable for population-level studies. Lastly, our protocol yields reproducible data for both δ15Noto and otolith N content in 17th century Atlantic cod otoliths. We find that 17th century cod are

  20. Sagittal otoliths description of Perciformes from Southeastern-South Brazil

    Directory of Open Access Journals (Sweden)

    César Santificetur

    2015-12-01

    Full Text Available The Collection of Teleostei Fish Otoliths of the Southeastern-Southern of Brazil (COSS-Brasil headquartered at the Oceanographic Institute, (IOUSP contains 65 species of Perciformes included in 30 families. In order to spread the modus operandi of the adopted analysis for the main characteristics of the sagittae we presented the results obtained for the families Centropomidae, Acropomatidae and Gerreidae. The classification of the otoliths morphological features followed Assis (2004 and Tuset et al. (2008. Fifteen features were analyzed and after, the frequency of the different types was calculated within and among each length classes of 20 mm. Statistical differences were analyzed by multiple χ2 tests (p>.0.05. The morphometric analysis included circularity and rectangularity. The main characteristics of the Centropomidae sagittae were: Shape: elliptic to trapezoidal; Posterior region: oblique or round; Sulcus acusticus: position median; orientation horizontal; morphology heterosulcoid; colliculum heteromorphic; ostium elliptic or rectangular; cauda tubular strongly curved; Circularity: 15.41 - 27.78; Rectangularity: 0.70 - 0.76. For the Acropomatidae we found: Anterior region: peaked; Dorsal edge: lobed to sinuate or sinuate to entire; Ventral edge: sinuate to entire; Sulcus acusticus: position median; orientation ascending or horizontal; opening ostial; morphology heterosulcoid; colliculum heteromorphic; ostium funnel-like or elliptic; Circularity: 15.75 - 19.77; Rectangularity: 0.60 - 0.74. The main characteristics of the Gerreidae were: Shape: elliptic; Anterior region: angled-round or peaked-round; Sulcus acusticus: position median or supramedian; orientation descending or horizontal; opening ostial; morphology heterosulcoid; colliculum heteromorphic; ostium funnel-like; Circularity: 14.11 - 22.86; Rectangularity: 0.53 - 0.74. We are preparing a practical guide of all the species of the collection including morphological, morphometric

  1. Variation in otolith macrostructure of Japanese flounder ( Paralichthys olivaceus): A method to discriminate between wild and released fish

    Science.gov (United States)

    Katayama, S.; Isshiki, T.

    2007-02-01

    The main objective of this study was to develop a method to discriminate between wild and hatchery-produced Japanese flounder, Paralichthys olivaceus, based on variations in otolith macrostructure. Otoliths of wild flounder were more elliptical than those of hatchery-produced fish, whereas otolith area and marginal coarseness showed no clear differences. Otolith morphometry did not vary significantly with water temperature or feeding conditions in rearing experiments. Reduced ellipticity in the otoliths of hatchery-produced fish could be caused by biotic and abiotic conditions after release. Throughout the study, it was found that otoliths of Japanese flounder reared at 15 and 20 °C regimes showed opaque zones regardless of feeding condition, while otolith of fish reared at 25 °C had translucent zones. The potential of thermal marks and secondary zones as a new mass-marking system is presented.

  2. Otolith chemistry reveals seamount fidelity in a deepwater fish

    Science.gov (United States)

    Régnier, Thomas; Augley, Julian; Devalla, Sandhya; Robinson, Craig D.; Wright, Peter J.; Neat, Francis C.

    2017-03-01

    There are thousands of seamounts (underwater mountains) throughout the world's deep oceans, many of which support diverse faunal communities and valuable fish stocks. Although seamounts are often geographically and bathymetrically isolated from one another, it is not clear how biologically isolated they are from one another. We analysed the chemical signature of the otoliths of a deepwater fish, the roundnose grenadier (Coryphaenoides rupestris) to test the null hypothesis that there is random exchange between individuals from a seamount and other adjacent areas. The fish were sampled on the Scottish west coast, from the Rosemary Bank seamount and two adjacent locations of similar depth, in the same year at roughly the same time of year. We used flow-injection inductively coupled plasma mass spectrometry to measure trace element concentrations from micro-milled portions of the otolith corresponding to adult and juvenile life history stages. The elemental signatures of the fish from the seamount were distinguishable from the fish from the two other areas during both the juvenile and adult life-history phase. We infer that once juveniles settle on the seamount they remain there for the rest of their lives. Evidence for population structure should be factored into exploitation strategies to prevent local depletion and is an important consideration with respect to Rosemary bank being included in a network of Marine Protected Areas around Scotland.

  3. Otolith mass asymmetry: natural, and after weightlessness and hypergravity

    Science.gov (United States)

    Lychakov, Dmitri

    It is believed that otolith mass asymmetry (OA) can play an essential role in genesis of vestibular space disturbances in human subjects and fish. This review poster presents data on values and characters of OA in animals of various species and classes and on the effect of weightlessness and hypergravity on OA; the issue of the effect of OA on vestibular and auditory functions also is considered (Lychakov, Rebane, 2004, 2005; Lychakov et al., 2006, 2008). In symmetric vertebrates, OA was shown to be fluctuating, its coefficient chiχ ranges from - 0.2 to + 0.2 (±± 20%). It should be stressed that in the overwhelming majority of individuals absolute values of chiχ selection. Unlike symmetric vertebrates, labyrinths of many Pleuronectiformes have pronounced OA. Otoliths in the lower labyrinth, on average, are significantly heavier than those in the upper labyrinth. The organs of flatfish represent the only example when OA, being directional, seem to play an essential role in lateralized behavior and are suggested to be used in the spatial localization of the source of sound. The short-term weightlessness and relatively weak hypergravity (> 3g as well as some diseases and age-related changes can indirectly enhance OA and cause some functional disturbances. This work was partly supported by Russian grant RFFI 14-04-00601.

  4. Contribution of water chemistry and fish condition to otolith chemistry: comparisons across salinity environments.

    Science.gov (United States)

    Izzo, C; Doubleday, Z A; Schultz, A G; Woodcock, S H; Gillanders, B M

    2015-06-01

    This study quantified the per cent contribution of water chemistry to otolith chemistry using enriched stable isotopes of strontium ((86) Sr) and barium ((137) Ba). Euryhaline barramundi Lates calcarifer, were reared in marine (salinity 40), estuarine (salinity 20) and freshwater (salinity 0) under different temperature treatments. To calculate the contribution of water to Sr and Ba in otoliths, enriched isotopes in the tank water and otoliths were quantified and fitted to isotope mixing models. Fulton's K and RNA:DNA were also measured to explore the influence of fish condition on sources of element uptake. Water was the predominant source of otolith Sr (between 65 and 99%) and Ba (between 64 and 89%) in all treatments, but contributions varied with temperature (for Ba), or interactively with temperature and salinity (for Sr). Fish condition indices were affected independently by the experimental rearing conditions, as RNA:DNA differed significantly among salinity treatments and Fulton's K was significantly different between temperature treatments. Regression analyses did not detect relations between fish condition and per cent contribution values. General linear models indicated that contributions from water chemistry to otolith chemistry were primarily influenced by temperature and secondly by fish condition, with a relatively minor influence of salinity. These results further the understanding of factors that affect otolith element uptake, highlighting the necessity to consider the influence of environment and fish condition when interpreting otolith element data to reconstruct the environmental histories of fish. © 2015 The Fisheries Society of the British Isles.

  5. Inter-population differences in otolith morphology are genetically encoded in the killifish Aphanius fasciatus (Cyprinodontiformes

    Directory of Open Access Journals (Sweden)

    Ali Annabi

    2013-06-01

    Full Text Available Inter-population differences in otolith shape, morphology and chemistry have been used effectively as indicators for stock assessment or for recognizing environmental adaptation in fishes. However, the precise parameters that affect otolith morphology remain incompletely understood. Here we provide the first direct support for the hypothesis that inter-population differences in otolith morphology are genetically encoded. The study is based on otolith morphology and two mitochondrial markers (D-loop, 16S rRNA of three natural populations of Aphanius fasciatus (Teleostei: Cyprinodontidae from Southeast Tunisia. Otolith and genetic data yielded congruent tree topologies. Divergence of populations likely results from isolation events in the course of the Pleistocene sea level drops. We propose that otolith morphology is a valuable tool for resolving genetic diversity also within other teleost species, which may be important for ecosystem management and conservation of genetic diversity. As reconstructions of ancient teleost fish faunas are often solely based on fossil otoliths, our discoveries may also lead to a new approach to research in palaeontology.

  6. Three-dimensional rendering of otolith growth using phase contrast synchrotron tomography.

    Science.gov (United States)

    Mapp, J J I; Fisher, M H; Atwood, R C; Bell, G D; Greco, M K; Songer, S; Hunter, E

    2016-05-01

    A three-dimensional computer reconstruction of a plaice Pleuronectes platessa otolith is presented from data acquired by the Diamond Light synchrotron, beamline I12, X-ray source, a high energy (53-150 keV) source particularly well suited to the study of dense objects. The data allowed non-destructive rendering of otolith structure, and for the first time allows otolith annuli (internal ring structures) to be analysed in X-ray tomographic images. © 2016 The Fisheries Society of the British Isles.

  7. Does DNA extraction affect the physical and chemical composition of historical cod (Gadus morhua) otoliths?

    DEFF Research Database (Denmark)

    Therkildsen, Nina Overgaard; Eg Nielsen, Einar; Hüssy, Karin

    2010-01-01

    applications. We examined the effects of three different DNA extraction methods on the elemental composition, the morphology, and the clarity of annual growth increments for successful age estimation of Atlantic cod (Gadus morhua) otoliths that had been archived for 0–31 years. The three extraction methods...... yielded DNA of comparable quality, and none of the methods caused major damage to the otoliths. Of the element concentrations measured, only Mg and Rb showed considerable changes resulting from DNA extraction. The physical properties of the otolith (morphology and clarity of annual growth increments) were...

  8. Factors determining variations in otolith microincrement width of demersal juvenile Baltic cod Gadus morhua

    DEFF Research Database (Denmark)

    Hüssy, Karin; Mosegaard, Henrik; Hinrichsen, H.H.

    2003-01-01

    Pelagic and demersal juvenile Baltic cod Gadus morhua L. were collected on the slope and the top of Rønne bank in the Baltic Sea during 2 cruises in November and December 1998. The objective of this study was to evaluate distinct changes in otolith increment width observed in demersal juveniles...... variable within and between individuals, in both the experimental and the field samples. The first change in increment pattern observed in the field samples was related to settling. The formation periodicity of increments within the different pattern intervals was confirmed with a growth model based...... on otolith growth rates of juvenile cod reared in the laboratory under different conditions. In this model, otolith growth rate was expressed as a function of rearing temperature and fish dry weight. Otolith growth of the field samples was calculated using ambient temperatures obtained from a 3D...

  9. Connectivity in the early life history of sandeel inferred from otolith microchemistry

    Science.gov (United States)

    Gibb, Fiona M.; Régnier, Thomas; Donald, Kirsty; Wright, Peter J.

    2017-01-01

    Connectivity is a central issue in the development, sustainability and effectiveness of networks of Marine Protected Areas (MPAs). In populations with site attached adults, connectivity is limited to dispersal in the pelagic larval stage. While biophysical models have been widely used to infer early dispersal, empirical evidence through sources such as otolith microchemistry can provide a means of evaluating model predictions. In the present study, connectivity in the lesser sandeel, Ammodytes marinus, was investigated using LA-ICP-MS otolith microchemistry. Otoliths from juveniles (age 0) were examined from four Scottish spawning areas predicted to differ in terms of larval retention rates and connectivity based on past biophysical models. There were significant spatial differences in otolith post-settled juvenile chemistry among locations at a scale of 100-400 km. Differences in near core chemistry pointed to three chemically distinct natal sources, as identified by a cluster analysis, contributing to settlement locations.

  10. [Laser destruction of labyrinthine receptors as a treatment for benign paroxysmal postural vertigo and otolith symptoms].

    Science.gov (United States)

    Garov, E V; Antonian, R G; Sheremet, A S

    2007-01-01

    Outcomes of surgical laser treatment are presented for 15 patients with resistant to conservative therapy benign paroxysmal postural vertigo (BPPV) and otolith-related disorders. Nine patients with Meniere's disease with BPPV (n=3) and otoliths (in all the patients) were exposed to laser impulses on the bony wall of the horizontal semicircular canal. The impulse was directed in the lumen of the canal in 6 patients with BPPV and otolith symptoms. In Meniere's patients vertigo stopped, hearing was at the preoperative level. Neither threy had BPPV nor otolith problems. The same results were obtained in 6 patients with the other diseases. Vestibular excitability of all surgically treated patients decreased to the fifth degree.

  11. Otolith atlas for the western Mediterranean, north and central eastern Atlantic

    Directory of Open Access Journals (Sweden)

    Victor M. Tuset

    2008-07-01

    Full Text Available The sagittal otolith of 348 species, belonging to 99 families and 22 orders of marine Teleostean fishes from the north and central eastern Atlantic and western Mediterranean were described using morphological and morphometric characters. The morphological descriptions were based on the otolith shape, outline and sulcus acusticus features. The morphometric parameters determined were otolith length (OL, mm, height (OH, mm, perimeter (P; mm and area (A; mm2 and were expressed in terms of shape indices as circularity (P2/A, rectangularity (A/(OL×OH, aspect ratio (OH/OL; % and OL/fish size. The present Atlas provides information that complements the characterization of some ichthyologic taxa. In addition, it constitutes an important instrument for species identification using sagittal otoliths collected in fossiliferous layers, in archaeological sites or in feeding remains of bony fish predators.

  12. Use of otolith-shape analysis for stock discrimination of Boops ...

    African Journals Online (AJOL)

    Oran, Bejaia and Annaba) between 2013 and 2016 were digitised and analysed for shape variation by elliptical Fourier analysis. Potential confounding sources of variation (fish length, age and sex, and left or right otolith position) were examined ...

  13. Validation of the periodicity of growth zone formation in the otoliths ...

    African Journals Online (AJOL)

    Validation of the periodicity of growth zone formation in the otoliths of four fish species from the Upper Zambezi ecoregion, southern Africa. Geraldine C. Taylor, Richard A. Peel, Clinton J. Hay, Olaf L.F. Weyl ...

  14. Enhancement of Otolith Specific Ocular Responses Using Vestibular Stochastic Resonance

    Science.gov (United States)

    Fiedler, Matthew; De Dios, Yiri E.; Esteves, Julie; Galvan, Raquel; Wood, Scott; Bloomberg, Jacob; Mulavara, Ajitkumar

    2011-01-01

    Introduction: Astronauts experience disturbances in sensorimotor function after spaceflight during the initial introduction to a gravitational environment, especially after long-duration missions. Our goal is to develop a countermeasure based on vestibular stochastic resonance (SR) that could improve central interpretation of vestibular input and mitigate these risks. SR is a mechanism by which noise can assist and enhance the response of neural systems to relevant, imperceptible sensory signals. We have previously shown that imperceptible electrical stimulation of the vestibular system enhances balance performance while standing on an unstable surface. Methods: Eye movement data were collected from 10 subjects during variable radius centrifugation (VRC). Subjects performed 11 trials of VRC that provided equivalent tilt stimuli from otolith and other graviceptor input without the normal concordant canal cues. Bipolar stochastic electrical stimulation, in the range of 0-1500 microamperes, was applied to the vestibular system using a constant current stimulator through electrodes placed over the mastoid process behind the ears. In the VRC paradigm, subjects were accelerated to 216 deg./s. After the subjects no longer sensed rotation, the chair oscillated along a track at 0.1 Hz to provide tilt stimuli of 10 deg. Eye movements were recorded for 6 cycles while subjects fixated on a target in darkness. Ocular counter roll (OCR) movement was calculated from the eye movement data during periods of chair oscillations. Results: Preliminary analysis of the data revealed that 9 of 10 subjects showed an average increase of 28% in the magnitude of OCR responses to the equivalent tilt stimuli while experiencing vestibular SR. The signal amplitude at which performance was maximized was in the range of 100-900 microamperes. Discussion: These results indicate that stochastic electrical stimulation of the vestibular system can improve otolith specific responses. This will have a

  15. Otolith-Canal Convergence in Vestibular Nuclei Neurons

    Science.gov (United States)

    Dickman, J. David

    1996-01-01

    During manned spaceflight, acute vestibular disturbances often occur, leading to physical duress and a loss of performance. Vestibular adaptation to the weightless environment follows within two to three days yet the mechanisms responsible for the disturbance and subsequent adaptation are still unknown In order to understand vestibular system function in space and normal earth conditions the basic physiological mechanisms of vestibular information co coding must be determined. Information processing regarding head movement and head position with respect to gravity takes place in the vestibular nuclei neurons that receive signals From the semicircular canals and otolith organs in the vestibular labyrinth. These neurons must synthesize the information into a coded output signal that provides for the head and eye movement reflexes as well as the conscious perception of the body in three-dimensional space The current investigation will for the first time. determine how the vestibular nuclei neurons quantitatively synthesize afferent information from the different linear and angular acceleration receptors in the vestibular labyrinths into an integrated output signal. During the second year of funding, progress on the current project has been focused on the anatomical orientation of semicircular canals and the spatial orientation of the innervating afferent responses. This information is necessary in order to understand how vestibular nuclei neurons process the incoming afferent spatial signals particularly with the convergent otolith afferent signals that are also spatially distributed Since information from the vestibular nuclei is presented to different brain regions associated with differing reflexive and sensory functions it is important to understand the computational mechanisms used by vestibular neurons to produce the appropriate output signal.

  16. Documenting utility of paddlefish otoliths for quantification of metals using inductively coupled plasma mass spectrometry

    Science.gov (United States)

    Long, James M.; Schaffler, James J.

    2013-01-01

    RATIONALE The otoliths of the inner ear of fishes record the environment of their surrounding water throughout their life. For paddlefish (Polyodon spathula), otoliths have not been routinely used by scientists since their detriments were outlined in the early 1940s. We sought to determine if paddlefish otoliths were useful for resolving elemental information contained within. METHODS Adult paddlefish were collected from two wild, self-sustaining populations in Oklahoma reservoirs in the Arkansas River basin. Juveniles were obtained from a hatchery in the Red River basin of Oklahoma. Otoliths were removed and laser ablation, inductively coupled plasma mass spectrometry (ICP-MS) was used to quantify eight elements (Li, Mg, Mn, Rb, Sr, Y, Ba, and Pb) along the core and edge portions, which were analyzed for differences between otolith regions and among paddlefish sources. RESULTS Differences were found among samples for six of the eight elements examined. Otoliths from Red River basin paddlefish born in a hatchery had significantly lower amounts of Mg and Mn, but higher levels of Rb than otoliths from wild paddlefish in the Arkansas River basin. Concentrations of Y, Sr, and Ba were reduced on the edges of adult paddlefish from both reservoirs compared with the cores. CONCLUSIONS This research shows the utility of using an ICP-MS analysis of paddlefish otoliths. Future research that seeks to determine sources of paddlefish production, such as which reservoir tributaries are most important for reproduction or what proportion of the population is composed of wild versus hatchery-produced individuals, appears promising. Published in 2013. This article is a U.S. Government work and is in the public domain in the USA.

  17. Effects of vestibular nerve transection on the calcium incorporation of fish otoliths

    Science.gov (United States)

    Anken, Ralf H.; Edelmann, Elke; Rahmann, Hinrich

    2001-08-01

    Previous investigations revealed that the growth of fish inner ear otoliths (otolith size and calcium-incorporation) depends on the amplitude and the direction of gravity, suggesting the existence of a (negative) feedback mechanism. In search for the regulating unit, the vestibular nerve was transected unilaterally in neonate swordtail fish ( Xiphophorus helleri) which were subsequently incubated in the calcium-tracer alizarin-complexone. Calcium incorporation ceased on the transected head sides, indicating that calcium uptake is neurally regulated.

  18. Neuronal feedback between brain and inner ear for growth of otoliths in fish

    Science.gov (United States)

    Anken, R. H.; Edelmann, E.; Rahmann, H.

    Previous investigations revealed that fish inner ear otolith growth (concerning otolith size and calcium-incorporation) depends on the amplitude and the direction of gravity, suggesting the existence of a (negative) feedback mechanism. In search for the regulating unit, the vestibular nerve was unilaterally transected in neonate swordtail fish ( Xiphophorus helleri) which were subsequently incubated in the calcium-tracer alizarin-complexone. Calcium incorporation ceased on the transected head sides, indicating that calcium uptake is neurally regulated.

  19. How can teleostean inner ear hair cells maintain the proper association with the accreting otolith?

    Science.gov (United States)

    Shiao, Jen-Chieh; Lin, Li-Yih; Horng, Jiun-Lin; Hwang, Pung-Pung; Kaneko, Toyoji

    2005-08-01

    The perception of equilibrium and sound in fish depends on the deflection of hair bundles of hair cell by the otolith. However, the accreting nature of teleostean otoliths poses a problem for maintenance of proper contact between the hair bundle and the otolith surface. Immunocytochemical staining localizes abundant proton-secreting H(+)-ATPase in the apical membrane of the hair cells. The H(+)-ATPase-mediated proton secretion into the endolymph causes an approximately 0.4-unit pH decrease, which was quantified by an H(+)-selective microelectrode. Thus, the hair cells maintain the proper distance from the otolith by neutralizing the alkaline endolymph to retard CaCO(3) deposition on the otolith opposite the sensory macula. Carbonic anhydrase, which hydrolyses CO(2) and produces HCO(3) (-) and H(+), was also localized in the hair cells. Ionocytes showed prominent immunostaining of carbonic anhydrase and Na(+)-K(+)-ATPase, indicating its role in transepithelial transport of HCO(3) (-) across the membranous labyrinth into the endolymph. Ionocytes form a ring closely surrounding the sensory macula. HCO(3) (-) secreted from the ionocytes may serve as a barrier to neutralize H(+) diffused from the sensory macula while keeping the endolymph alkaline outside the sensory macula. The ingenious arrangement of ionocytes and hair cells results in a unique sculptured groove, which is a common feature on the proximal surface of all teleostean otoliths. (c) 2005 Wiley-Liss, Inc.

  20. Swimming Behaviour and Otolith Characteristics of wildtype and mutant Zebrafish (AIE) under diminished Gravity Conditions

    Science.gov (United States)

    Weigele, J.; Anken, R.; Hilbig, R.

    During microgravity humans often suffer from sensorimotor disorders e g motion sickness a kinetosis Using fish as vertebrate model systems we could previously provide ample evidence that the individually different susceptibility to such disorders is based on an individually differently pronounced asymmetric mineralisation calcification of inner ear stones otoliths In the course of a preliminary study we subjected mutant zebrafish Danio rerio due to malformation of the inner ear - see below - this mutant was termed Asymmetric Inner Ear AIE to diminished gravity conditions during parabolic aircraft flight PF As compared to wildtype WT animals the mutants showed a pronounced kinetotic behaviour The gross-morphology of the inner ears of AIE and WT animals strikingly differed In WT specimens the saccular otoliths were located at the periphery of the inner ear whereas the utricular stones were positioned mediad as it is usually the case in teleosts in most AIE animals dissected however the respective otoliths were positioned in an opposite arrangement Moreover the mutants sported transparent otoliths whereas the otoliths of WT specimens had an opaque appearance This finding clearly indicates that mutant otoliths differed from wildtype ones in their lattice structure i e the calcium carbonate polymorph and thus the compostion of the proteinacious matrix which is a template for calcium carbonate deposition In the course of the present study the PF experiment is scheduled to be carried out in March 2006 we intend to statistically verify

  1. FLUCTUATING ASYMMETRY IN THE OTOLITH WIDTH OF Carangoides caeruleopinnatus (CARANGIDAE COLLECTED FROM MUSCAT CITY COAST ON THE SEA OF OMAN

    Directory of Open Access Journals (Sweden)

    Dawood Al-Mamari

    2012-10-01

    Full Text Available The fluctuating asymmetry in two otolith dimensions, the length and width of adult teleost Carangoides caeruleopinnatus were calculated. The highest asymmetry value was observed in the otolith width. The fish length groups 201-210 and 281-290 mm showed the lowest and the highest value of asymmetry respectively. In addition, few fish length groups have shown zero value for otolith size asymmetry. Different pollutants and their presence in the area appeared to be one of the reasons that cause the asymmetry in this species. A trend of increase in the asymmetry values with the fish length was noticed for the otolith length and width.

  2. Carbon isotopes in otolith amino acids identify residency of juvenile snapper (Family: Lutjanidae) in coastal nurseries

    Science.gov (United States)

    McMahon, K. W.; Berumen, M. L.; Mateo, I.; Elsdon, T. S.; Thorrold, S. R.

    2011-12-01

    This study explored the potential for otolith geochemistry in snapper (Family: Lutjanidae) to identify residency in juvenile nursery habitats with distinctive carbon isotope values. Conventional bulk otolith and muscle stable isotope analyses (SIA) and essential amino acid (AA) SIA were conducted on snapper collected from seagrass beds, mangroves, and coral reefs in the Red Sea, Caribbean Sea, and Pacific coast of Panama. While bulk stable isotope values in otoliths showed regional differences, they failed to distinguish nursery residence on local scales. Essential AA δ13C values in otoliths, on the other hand, varied as a function of habitat type and provided a better tracer of residence in different juvenile nursery habitats than conventional bulk otolith SIA alone. A strong linear relationship was found between paired otolith and muscle essential AA δ13C values regardless of species, geographic region, or habitat type, indicating that otolith AAs recorded the same dietary information as muscle AAs. Juvenile snapper in the Red Sea sheltered in mangroves but fed in seagrass beds, while snapper from the Caribbean Sea and Pacific coast of Panama showed greater reliance on mangrove-derived carbon. Furthermore, compound-specific SIA revealed that microbially recycled detrital carbon, not water-column-based new phytoplankton carbon, was the primary carbon source supporting snapper production on coastal reefs of the Red Sea. This study presented robust tracers of juvenile nursery residence that will be crucial for reconstructing ontogenetic migration patterns of fishes among coastal wetlands and coral reefs. This information is key to determining the importance of nursery habitats to coral reef fish populations and will provide valuable scientific support for the design of networked marine-protected areas.

  3. Carbon isotopes in otolith amino acids identify residency of juvenile snapper (Family: Lutjanidae) in coastal nurseries

    KAUST Repository

    McMahon, Kelton

    2011-08-26

    This study explored the potential for otolith geochemistry in snapper (Family: Lutjanidae) to identify residency in juvenile nursery habitats with distinctive carbon isotope values. Conventional bulk otolith and muscle stable isotope analyses (SIA) and essential amino acid (AA) SIA were conducted on snapper collected from seagrass beds, mangroves, and coral reefs in the Red Sea, Caribbean Sea, and Pacific coast of Panama. While bulk stable isotope values in otoliths showed regional differences, they failed to distinguish nursery residence on local scales. Essential AA δ13C values in otoliths, on the other hand, varied as a function of habitat type and provided a better tracer of residence in different juvenile nursery habitats than conventional bulk otolith SIA alone. A strong linear relationship was found between paired otolith and muscle essential AA δ13C values regardless of species, geographic region, or habitat type, indicating that otolith AAs recorded the same dietary information as muscle AAs. Juvenile snapper in the Red Sea sheltered in mangroves but fed in seagrass beds, while snapper from the Caribbean Sea and Pacific coast of Panama showed greater reliance on mangrove-derived carbon. Furthermore, compound-specific SIA revealed that microbially recycled detrital carbon, not water-column-based new phytoplankton carbon, was the primary carbon source supporting snapper production on coastal reefs of the Red Sea. This study presented robust tracers of juvenile nursery residence that will be crucial for reconstructing ontogenetic migration patterns of fishes among coastal wetlands and coral reefs. This information is key to determining the importance of nursery habitats to coral reef fish populations and will provide valuable scientific support for the design of networked marine-protected areas. © 2011 Springer-Verlag.

  4. Microstructure of otoliths; age readings and growth determinations of silver hake (Merluccius bilinearis) on early development stages on the Scotian Shelf

    National Research Council Canada - National Science Library

    Markov, Yu.A; Sherstykov, A.I

    1991-01-01

    Based on the specialized collections of otoliths taken from embryos, larvae and fries of the Scotian silver hake the equations to calculate the absolute and relative body growth rates, otolith growth...

  5. The use of otolith morphology to indicate the stock structure of common coral trout (Plectropomus leopardus) on the Great Barrier Reef, Australia

    OpenAIRE

    Bergenius, Mikaela A. J.; Begg, Gavin A.; Mapstone, Bruce D.

    2006-01-01

    We investigated the use of otolith morphology to indicate the stock structure of an exploited serranid coral reef fish, Plectropomus leopardus, on the Great Barrier Reef (GBR), Australia. Otoliths were measured by traditional one-and two-dimensional measures (otolith length, width, area, perimeter, circularity, and rectangularity), as well as by Fourier analysis to capture the finer details of otolith shape. Variables were compared among four regions of the GBR separated by hundreds of kilome...

  6. Does otolith organ dysfunction influence outcomes after a customized program of vestibular rehabilitation?

    Science.gov (United States)

    Murray, Katherine J; Hill, Keith; Phillips, Bev; Waterston, John

    2010-06-01

    Vestibular rehabilitation (VR) is a successful approach to the treatment of vestibular dysfunction. The purpose of this study was to investigate the influence of otolith dysfunction on the response to VR in individuals with a peripheral vestibular disorder. Eighteen participants with loss of semicircular canal function only, and 29 participants with combined loss of semicircular canal and otolith organ function were recruited. All participants received a comprehensive clinical assessment before and after an 8-week customized program of VR. Both groups achieved significant improvements on most measures at the end of the 8-week VR program. However, no significant differences were identified between participants with versus without otolith dysfunction with respect to change in symptom severity (P = .81), self-perceived handicap (P = .92), functional limitations (P = .93), or balance performance after VR. Otolith dysfunction does not significantly influence the response to rehabilitation of individuals with a peripheral vestibular disorder. Vestibular rehabilitation is associated improvements in symptom severity, self-perceived handicap, and balance function in individuals with otolith dysfunction.

  7. A new method to reconstruct fish diet and movement patterns from δ 13 C values in otolith amino acids

    KAUST Repository

    McMahon, Kelton W.

    2011-08-01

    Fish ecologists have used geochemical values in otoliths to examine habitat use, migration, and population connectivity for decades. However, it remains difficult to determine an unambiguous dietary δ 13C signature from bulk analysis of otolith. Studies to date have focused on the aragonite component of otoliths with less attention paid to the organic fraction. We describe the application of compound-specific stable isotope analysis (SIA) to analyze amino acid (AA) δ 13C values from small amounts (<1 mg) of otolith powder. We examined δ 13C values of otolith and muscle AAs from a reef-associated snapper (Lutjanus ehrenbergii (Peters, 1869)) collected along a carbon isotope gradient (isoscape) from seagrass beds to coral reefs. Carbon isotope values in otolith and muscle samples were highly correlated within and among coastal habitats. Moreover, δ 13C values of otolith AAs provided a purely dietary record that avoided dilution from dissolved inorganic carbon. Otolith AAs served as a robust tracer of δ 13C values at the base of the food web, making compound-specific SIA a powerful tool for dietary reconstructions and tracking the movement of fishes across isoscapes.

  8. Effects of sex, stock, and environment on the shape of known-age Atlantic cod ( Gadus morhua ) otoliths

    DEFF Research Database (Denmark)

    Cardinale, M.; Doering-Arjes, P.; Kastowsky, M.

    2004-01-01

    The effects of sex, stock, and environment on the shape of known-age Atlantic cod (Gadus morhua) otoliths from the Faroe Islands were investigated. Moreover, the feasibility of otolith shape analysis for stock identification was evaluated. The shape was described by using several normalized Fourier...... descriptors and morphometric variables. There were no consistent differences between the left and right otoliths and between sexes within different age classes, stocks, and environments. With our experimental design, we could evaluate the relative importance of genetic and environmental conditions (water....... The significant differences in otolith shape between Faroe Bank and Faroe Plateau cod stocks provided a phenotypic basis for stock separation. Stock and environmental influences were substantial in determining the shape of cod otoliths....

  9. Micro-PIXE study of whole otolith of Anguilla japonica at elver stage

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Y. [Applied Ion Beam Physics Laboratory, Institute of Modern Physics, Fudan University, Shanghai 200433 (China); Guo, H.; Wei, K.; Tang, W. [Institute of Life Science, Shanghai Fisheries University, Shanghai 200090 (China); Satoh, T.; Ohkubo, T.; Yamazaki, A.; Takano, K.; Kamiya, T. [Takasaki Advanced Radiation Research Institute, JAEA, Gunma 370-1292 (Japan); Shen, H., E-mail: haoshen@fudan.edu.c [Applied Ion Beam Physics Laboratory, Institute of Modern Physics, Fudan University, Shanghai 200433 (China); Yang, M.; Mi, Y. [Applied Ion Beam Physics Laboratory, Institute of Modern Physics, Fudan University, Shanghai 200433 (China)

    2010-06-15

    Strontium and calcium contents, within the otolith of Anguilla japonica, were measured by external micro-PIXE. According to the measured metamorphic checks, each otolith was divided into three stages. Comparing with the Sr:Ca ratios in stage 2, the ratios in stage 1 had two different trends. Among these fish, it may reflect their maternal condition was not the same. The ratios in stage 3 which was corresponding to the estuarine habitat were smaller than that in any other stage which was corresponding to the ocean habitat in each otolith. Suggested by our results, the eels from the spawning site may separate into two groups when they are near to the south of Taiwan, and then move to the different estuaries in China. It could be proposed that, in general, the migration direction is from south to north along the east coast in China.

  10. Matching watershed and otolith chemistry to establish natal origin of an endangered desert lake sucker

    Science.gov (United States)

    Strohm, Deanna D.; Budy, Phaedra; Crowl, Todd A.

    2017-01-01

    Stream habitat restoration and supplemental stocking of hatchery-reared fish have increasingly become key components of recovery plans for imperiled freshwater fish; however, determining when to discontinue stocking efforts, prioritizing restoration areas, and evaluating restoration success present a conservation challenge. In this study, we demonstrate that otolith microchemistry is an effective tool for establishing natal origin of the June Sucker Chasmistes liorus, an imperiled potamodromous fish. This approach allows us to determine whether a fish is of wild or hatchery origin in order to assess whether habitat restoration enhances recruitment and to further identify areas of critical habitat. Our specific objectives were to (1) quantify and characterize chemical variation among three main spawning tributaries; (2) understand the relationship between otolith microchemistry and tributary chemistry; and (3) develop and validate a classification model to identify stream origin using otolith microchemistry data. We quantified molar ratios of Sr:Ca, Ba:Ca, and Mg:Ca for water and otolith chemistry from three main tributaries to Utah Lake, Utah, during the summer of 2013. Water chemistry (loge transformed Sr:Ca, Ba:Ca, and Mg:Ca ratios) differed significantly across all three spawning tributaries. We determined that Ba:Ca and Sr:Ca ratios were the most important variables driving our classification models, and we observed a strong linear relationship between water and otolith values for Sr:Ca and Ba:Ca but not for Mg:Ca. Classification models derived from otolith element : Ca signatures accurately sorted individuals to their experimental tributary of origin (classification tree: 89% accuracy; random forest model: 91% accuracy) and determined wild versus hatchery origin with 100% accuracy. Overall, this study aids in evaluating the effectiveness of restoration, tracking progress toward recovery, and prioritizing future restoration plans for fishes of conservation

  11. Using otolith microstructure to analyse growth of juvenile Baltic cod Gadus morhua

    DEFF Research Database (Denmark)

    Hüssy, Karin; Mosegaard, Henrik; Hinrichsen, H.H.

    2003-01-01

    Pelagic and demersal juvenile Baltic cod Gadus morhua L. were collected on the slope and the top of Rønne bank in the Baltic Sea during 2 cruises in November and December 1998. The growth, age at settling and vertical migration pattern were studied by otolith microstructure analysis. The relation......Pelagic and demersal juvenile Baltic cod Gadus morhua L. were collected on the slope and the top of Rønne bank in the Baltic Sea during 2 cruises in November and December 1998. The growth, age at settling and vertical migration pattern were studied by otolith microstructure analysis...

  12. Using data storage tags to link otolith macrostructure in Baltic cod Gadus morhua with environmental conditions

    DEFF Research Database (Denmark)

    Hüssy, Karin; Nielsen, Birgitte; Mosegaard, Henrik

    2009-01-01

    We examined otolith opacity of Baltic cod in relation to environmental conditions in order to evaluate the formation mechanisms of seasonal patterns used in age determination. Adult fish were tagged with data storage tags (DSTs) and a permanent mark was induced in the otoliths by injection...... as expected-but in non-spawning fish only. In spawners, the general trend was a decrease in opacity from pre- to post spawning. A significant - but positive - temperature effect was only found in the pre-spawning period. The negative effects during and following spawning were not significant. In spawners...

  13. Smooth pursuit eye movements and otolith-ocular responses are differently impaired in cerebellar ataxia.

    Science.gov (United States)

    Anastasopoulos, D; Haslwanter, T; Fetter, M; Dichgans, J

    1998-08-01

    Horizontal and vertical smooth pursuit was compared with otolith-ocular responses in 11 patients with cerebellar ataxia and 21 normal subjects using three-dimensional magnetic search coil eye movement recordings. Otolith-ocular responses were investigated during off-vertical axis rotation. This stimulus induces nystagmus consisting of the exponentially decaying canalicular response, and an eye-velocity modulation and offset which arise from the excitation of the otoliths by the gravity vector, which lasts as long as the rotation continues. Otolith-ocular reflexes are intimately interrelated with visual tracking when real targets are viewed during linear motion. The responses of both the translational vestibulo-ocular reflex and the pursuit system have been shown to be linearly dependent on the inverse of the viewing distance, so that a common central pathway for the two systems has been suggested, probably travelling through the cerebellum. Thus, the aim of the study was to evaluate to what extent these reflexes are disturbed in cerebellar disease. The results confirm the earlier notion that in normal subjects pursuit performance is better for horizontal than for vertical tracking, and that it is better for upward than for downward tracking. This pattern is also found in patients. In addition, smooth pursuit performance is clearly degraded in patients, but the modulation of eye-velocity during off-vertical axis rotation is enhanced. Since the amount of this enhancement does not correlate with the amount of pursuit impairment, degradation of smooth pursuit and pathological enhancement of otolith-ocular responses seem to be independent effects of cerebellar degeneration. Thus, the increase in the otolith-ocular response in patients cannot be attributed to adaptational mechanisms trying to overcome the smooth pursuit deficiency; it is more likely to represent pathological disinhibition of otolith derived responses. The absence of compensatory eye-velocity offset

  14. Otolith development in larval and juvenile Schizothorax davidi: ontogeny and growth increment characteristics

    Science.gov (United States)

    Yan, Taiming; Hu, Jiaxiang; Cai, Yueping; Xiong, Sen; Yang, Shiyong; Wang, Xiongyan; He, Zhi

    2017-09-01

    Laboratory-reared Schizothorax davidi larvae and juveniles were examined to assess the formation and characteristics of David's schizothoracin otoliths. Otolith development was observed and their formation period was verified by monitoring larvae and juveniles of known age. The results revealed that lapilli and sagittae developed before hatching, and the first otolith increment was identified at 2 days post hatching in both. The shape of lapilli was relatively stable during development compared with that of sagittae; however, growth of four sagittae and lapilli areas was consistent, but the posterior area grew faster than the anterior area and the ventral surface grew faster than the dorsal surface. Similarly, the sum length of the radius of the anterior and posterior areas on sagittae and lapilli were linearly and binomially related to total fish length, respectively. Moreover, daily deposition rates were validated by monitoring knownage larvae and juveniles. The increase in lapilli width was 1.88±0.080 0 μm at the ninth increment, which reached a maximum and the decreased gradually toward the otolith edge, whereas that of sagittae increased more slowly. These results illustrate the developmental biology of S. davidi, which will aid in population conservation and fish stock management.

  15. Otoliths in situ from Sarmatian (Middle Miocene) fishes of the Paratethys. Part I

    DEFF Research Database (Denmark)

    Schwarzhans, Werner; Carnevale, Giorgio; Bannikov, Alexandre F.

    2017-01-01

    Several well-preserved otoliths were extracted from four slabs containing fish specimens of Atherina suchovi. Atherina suchovi is one of the five Atherina species recorded from the Middle Miocene of the Central and Eastern Paratethys established on articulated skeletal remains. This corresponds t...

  16. Identifying blue whiting (Micromesistius poutassou) stock structure in the Northeast Atlantic by otolith shape analysis

    DEFF Research Database (Denmark)

    Mahe, Kélig; Oudard, Clémence; Mille, Tiphaine

    2016-01-01

    Information on stock identification and spatial stock structure provide a basis for understanding fish population dynamics and improving fisheries management. In this study, otolith shape analysis was used to study the stock structure of blue whiting (Micromesistius poutassou) in the northeast At...

  17. Otoliths in continental shelf and slope surficial sediments off Saurashtra, Arabian Sea, India and their significance

    Digital Repository Service at National Institute of Oceanography (India)

    Nigam, R.; John, S.; Rana, R.S.

    is in progress and will be reported in due course. This preliminary report which is the first report from the northern Arabian Sea on fossil fish otolith may help as an additional tool in the reconstruction of paleoenvironment and in assessing the latitudinal...

  18. The utricular otoliths, lapilli, of teleosts: their morphology and relevance for species identification and systematics studies

    Directory of Open Access Journals (Sweden)

    Carlos A. Assis

    2005-06-01

    Full Text Available The present study describes the general morphology of the utricular otoliths, lapilli, of teleost fishes, proposes a terminology for their parts, identifies their two major morphological types, provides some examples of their use in species identification, and discusses their usefulness in studies of fish phylogeny and systematics.

  19. Otolith microstructure analysis to resolve seasonal patterns of hatching and settlement in western Baltic cod

    DEFF Research Database (Denmark)

    Rehberg-Haas, Sabine; Hammer, Cornelius; Hillgruber, Nicola

    2012-01-01

    and to differentiate between true annuli and secondary structures such as settlement checks. Otoliths were collected from fish off Fehmarn Island in 2008 and 2009, and were examined for macrostructural and microstructural patterns using light and scanning electron microscopy. All fish examined were age-0. Back...

  20. Use of an otolith-deficient mutant in studies of fish behavior under microgravity

    Science.gov (United States)

    Ijiri, K.; Mizuno, R.; Eguchi, H.

    In Medaka (Oryzias latipes ), fish of a mutant strain (ha strain) had a malfunction in otolith-vestibular system. The phenotype is expressed when the fish have this recessive gene h a) in a homozygous fashion, and the gene is autosomal. Their( difference from the normal fish was first recognizable in their embryonic stages, with abnormally larger ear vesicles and absence of otoliths called Lapillus inside the vesicles. The time-course study was carried out for the subsequent development of their otoliths. X ray phot ographs of the fish revealed that some adult fish of ha- strain still lack a pair of Lapillus, which mainly serve in sensing the direction of gravity, while others have formed the otoliths partially or completely. Changing the light direction within each day, the ha mutant fish were reared from hatching to young fish. The fish treated showed less dependence on gravity even at the age of 50 days or more. Parabolic flight experiments were carried out to observe the fish behavior under microgravity for ha strain.

  1. Evaluation of diagnostic tests of the otolith organs and their application in various vestibular pathologies

    NARCIS (Netherlands)

    Winters, S.M.

    2014-01-01

    Current vestibular testing is limited. The general function of the vestibular system on both sides of the head can be tested, and one part of the peripheral vestibular organ, the horizontal semicircular canal, can be tested unilaterally. However, recently a test for the function of the otolith

  2. The potential dysfunction of otolith organs in patients after mumps infection.

    Directory of Open Access Journals (Sweden)

    Yu-Juan Zhou

    Full Text Available To investigate the relationship between mumps and the extent of hearing impairment and otolith organ damage.A total of 27 patients with unilateral hearing impairment following mumps were enrolled. The degrees of hearing loss and otolith organ damage were confirmed by audiometric and vestibular evoked myogenic potential [VEMP] tests. All the results were compared and analyzed using Stata 13.0 software for Windows.The VEMP thresholds of the affected ears were significantly higher than those of the unaffected ears in both tests (cervical VEMP [cVEMP] test and ocular VEMP [oVEMP] test; p = 0.000 and 0.001, respectively. The mean cVEMP and oVEMP threshold values of the affected ears with hearing impairment for ≤10 years were significantly lower than those of affected ears with hearing impairment for >10 years [p = 0.009 and 0.004, respectively].Deafness resulting from mumps is usually profound and permanent, which indicates severe damage to the cochlea due to the disease. The functions of otolith organs in the vestibular system are also impaired. Over time, the function of the otolith organs or their neural pathway may suffer secondary damage.

  3. Experimental Evaluation of Stable Isotope Fractionation in Fish Muscle and Otoliths

    Science.gov (United States)

    We investigated an unresolved question in the use of stable isotopes to determine diet and trophic position of fish using both muscle and otoliths. We determined: i) the degree of fractionation of δ13C and δ15N between diet and muscle, and assessed if fractionation was consistent...

  4. Life history of the Small Sandeel, Ammodytes tobianus, inferred from otolith microchemistry. A methodological approach

    Science.gov (United States)

    Laugier, F.; Feunteun, E.; Pecheyran, C.; Carpentier, A.

    2015-11-01

    Knowledge of life history and connectivity between essential ecological habitats are relevant for conservation and management of species and some natural tracers could be used to study the lifecycles of small or short-lived marine fishes. Although sandeels are central in marine food webs and are key species, there is incomplete knowledge about population mixing and migration patterns. For the first time the use of the otolith microchemistry on sandeel species is evaluated in the case of the Small Sandeel. Variations in microchemical fingerprints of 13 trace elements are performed with a Femtosecond LA-ICPM from the core to the margin of sagittal otolith and are compared within and between otoliths extracted from 34 fishes sampled in three different sites along the coast of the south-western English Channel in France. Firstly, preliminary investigations on the validity of the method revealed that Mg/Ca was the only ratio significantly dependant on fish ontogeny and sampling season. Secondly, the Mn/Ca, Zn/Ca, and Cu/Ca ratios enabled us to significantly discriminate among sampling sites. Thirdly, microchemical fingerprints of each life stage varied significantly among sampling sites but not within them, suggesting high site fidelity over relatively short distances. Finally, the fingerprints of all life stages were significantly different from those of the larval and metamorphosis stages. The otolith microchemistry could detect change of signature relative to the shift from a pelagic behaviour to a resident bentho-pelagic behaviour during the middle of the juvenile stage in Small Sandeels. Hence, analysis of trace element fingerprints in otoliths appears to be a valuable method to further studies on ontogenic habitat change, population mixing and variation of life history and be helpful for the management at local or regional scales of short-lived species such as those belonging to other Ammodytidae.

  5. Assessment of functional development of the otolithic system in growing children: a review.

    Science.gov (United States)

    Young, Yi-Ho

    2015-04-01

    Although the caloric test, rotational test, and posturography have been used to investigate balance function conventionally, and they are older than tests of otolithic organs, yet it seems that most clinicians are less familiar with the development of otolithic (saccular and utricular) function in children. This study reviewed the electrophysiological testing used to assess the functional development of the otolithic system in growing children. Based on the literature, studies of cervical vestibular-evoked myogenic potential (cVEMP) and ocular VEMP (oVEMP) tests in children ranging from newborns, small children to adolescents were reviewed. Papers concerning foam posturography in children were also included. The cVEMPs can be elicited in newborns at day 5, whereas the oVEMPs are absent in neonatal period. When children grow to 2 years old, the oVEMPs can be induced with eyes closed condition, while the oVEMPs with eyes up condition can be elicited in children aged >3 years old, with the characteristic parameters similar to adult levels. In contrast with cVEMPs, it is until the neck length >15.3cm (aldolesence), one need not account for neck length in evaluating cVEMP latency. Additionally, foam posturography indicated by the Romberg quotient of the sway velocity/area on foam pad is considered to reflect the otolithic function, which reached adult levels when the children at 12 years old. For the functional development of the otolithic system in growing children to approach adult levels, the earliest occurrence is the oVEMP test, followed by the foam posturography, and cVEMP test. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  6. On the intraspecific variation in morphometry and shape of sagittal otoliths of common sardine, Strangomera bentincki, off central-southern Chile

    Directory of Open Access Journals (Sweden)

    Sandra Curin-Osorio

    2012-11-01

    Full Text Available Size and shape of fish otoliths are species-specific, but some species also display intraspecific variations. The common sardine, Strangomera bentincki, is a small pelagic fish inhabiting a seasonal upwelling ecosystem off central-southern Chile, having two discrete spawning sites along its latitudinal distribution. Otoliths of specimens were collected from commercial catches in Talcahuano and Corral, representing the central and south spawning zones. On the basis of otolith images, size-based shape descriptors were used to detect ontogenetic variation, and morphometric variables (length, breadth, area, perimeter and weight were used to detect geographical differences in size and shape of otoliths. Outline analysis was studied on the basis of elliptic Fourier descriptors through multivariate statistical procedures. Size-based shape descriptors showed that otolith shape starts to be stable for fish larger than 12 cm total length, which keep an elliptical form. Morphometric variables for fish larger than 12 cm revealed intraspecific variation between central and south zones, which were associated with otolith weight and breadth. Outline analysis did not reveal significant spatial differences, but extreme intraspecific variation was due to the antirostrum, excisure, and posterior part of otoliths. Intraspecific variation in otolith size could be linked to differences in each spawning habitat and related to geographical origin, whose differences are not clearly identified. It is concluded that intraspecific variability in morphometric variables of sardine otoliths revealed geographic differences in size that are not attributable to allometric effects, and that otolith shape was similar between specimens from different geographic origin.

  7. Selecting statistical models and variable combinations for optimal classification using otolith microchemistry.

    Science.gov (United States)

    Mercier, Lény; Darnaude, Audrey M; Bruguier, Olivier; Vasconcelos, Rita P; Cabral, Henrique N; Costa, Maria J; Lara, Monica; Jones, David L; Mouillot, David

    2011-06-01

    Reliable assessment of fish origin is of critical importance for exploited species, since nursery areas must be identified and protected to maintain recruitment to the adult stock. During the last two decades, otolith chemical signatures (or "fingerprints") have been increasingly used as tools to discriminate between coastal habitats. However, correct assessment of fish origin from otolith fingerprints depends on various environmental and methodological parameters, including the choice of the statistical method used to assign fish to unknown origin. Among the available methods of classification, Linear Discriminant Analysis (LDA) is the most frequently used, although it assumes data are multivariate normal with homogeneous within-group dispersions, conditions that are not always met by otolith chemical data, even after transformation. Other less constrained classification methods are available, but there is a current lack of comparative analysis in applications to otolith microchemistry. Here, we assessed stock identification accuracy for four classification methods (LDA, Quadratic Discriminant Analysis [QDA], Random Forests [RF], and Artificial Neural Networks [ANN]), through the use of three distinct data sets. In each case, all possible combinations of chemical elements were examined to identify the elements to be used for optimal accuracy in fish assignment to their actual origin. Our study shows that accuracy differs according to the model and the number of elements considered. Best combinations did not include all the elements measured, and it was not possible to define an ad hoc multielement combination for accurate site discrimination. Among all the models tested, RF and ANN performed best, especially for complex data sets (e.g., with numerous fish species and/or chemical elements involved). However, for these data, RF was less time-consuming and more interpretable than ANN, and far more efficient and less demanding in terms of assumptions than LDA or QDA

  8. Effect of ocean acidification on otolith development in larvae of a tropical marine fish

    OpenAIRE

    Munday, P. L.; V. Hernaman; Dixson, D. L.; Thorrold, S. R.

    2011-01-01

    Calcification in many invertebrate species is predicted to decline due to ocean acidification. The potential effects of elevated pCO2 and reduced carbonate saturation state on other species, such as fish, are less well understood. Fish otoliths (earbones) are composed of aragonite, and thus, might be susceptible to either the reduced availability of carbonate ions in seawater at low pH, or to changes in extracellular concentrations of bicarbonate and ...

  9. Acoustically Induced Streaming Flows near a Model Cod Otolith and their Potential Implications for Fish Hearing

    Energy Technology Data Exchange (ETDEWEB)

    Kotas, Charlotte W [ORNL; Rogers, Peter [Georgia Institute of Technology; Yoda, Minami [Georgia Institute of Technology

    2011-01-01

    The ears of fishes are remarkable sensors for the small acoustic disturbances associated with underwater sound. For example, each ear of the Atlantic cod (Gadus morhua) has three dense bony bodies (otoliths) surrounded by fluid and tissue, and detects sounds at frequencies from 30 to 500 Hz. Atlantic cod have also been shown to localize sounds. However, how their ears perform these functions is not fully understood. Steady streaming, or time-independent, flows near a 350% scale model Atlantic cod otolith immersed in a viscous fluid were studied to determine if these fluid flows contain acoustically relevant information that could be detected by the ear s sensory hair cells. The otolith was oscillated sinusoidally at various orientations at frequencies of 8 24 Hz, corresponding to an actual frequency range of 280 830 Hz. Phaselocked particle pathline visualizations of the resulting flows give velocity, vorticity, and rate of strain fields over a single plane of this mainly two-dimensional flow. Although the streaming flows contain acoustically relevant information, the displacements due to these flows are likely too small to explain Atlantic cod hearing abilities near threshold. The results, however, may suggest a possible mechanism for detection of ultrasound in some fish species.

  10. Lake trout otolith chronologies as multidecadal indicators of high-latitude freshwater ecosystems

    Science.gov (United States)

    Black, B.A.; Von Biela, V.R.; Zimmerman, C.E.; Brown, Randy J.

    2013-01-01

    High-latitude ecosystems are among the most vulnerable to long-term climate change, yet continuous, multidecadal indicators by which to gauge effects on biology are scarce, especially in freshwater environments. To address this issue, dendrochronology (tree-ring analysis) techniques were applied to growth-increment widths in otoliths from lake trout (Salvelinus namaycush) from the Chandler Lake system, Alaska (68.23°N, 152.70°W). All otoliths were collected in 1987 and exhibited highly synchronous patterns in growth-increment width. Increments were dated, the widths were measured, and age-related growth declines were removed using standard dendrochronology techniques. The detrended time series were averaged to generate an annually resolved chronology, which continuously spanned 1964–1984. The chronology positively and linearly correlated with August air temperature over the 22-year interval (p metabolic rate or lake productivity. Given the broad distribution of lake trout within North America, this study suggests that otolith chronologies could be used to examine responses between freshwater ecosystems and environmental variability across a range of temporal and spatial scales.

  11. Comparative Analysis of Otolith Features of Tarek (Alburnus tarichi (Güldenstädt, 1814 from Different Lakes across Van Basin (Van, Erçek, Nazik, Aygır (Turkey

    Directory of Open Access Journals (Sweden)

    Semra SAYGIN

    2017-08-01

    Full Text Available In the present study, a comparison of the otolith morphology of Alburnus tarichi, collected from different localities throughout Van Basin was carried on. A total of 351 specimens of A.tarichi collected by trammel nets from four different localities (Van, Erçek, Nazik, Aygır during the period April-May 2015 were examined. Fork length and body weight of the specimens ranged between 9.9-24.6 cm and 8.4-176.5 g, respectively. Lagenar otoliths were removed discriminating as left and right. Otolith length (OL, otolith breadth (OB and otolith weight (OW were collected. Comparisons of right-left otolith measurements were tested by paired t test. Comparisons of otolith breadth, length and weight of A. tarichi among all localities were tested by ANOVA. There were no significant difference in terms of otolith length and weight between right and left otoliths but there were statistically significant difference in terms of otolith breadth between the specimens collected in Lake Van and Lake Erçek. There were no differences between right and left otolith measurements in Lake Nazik and Lake Aygır. Comparing all localities together, otolith length, breadth and weight were different from each other for four localities. The power model was applied to estimate the relationships between the otolith measurements and fish length.

  12. UREA/ammonium ion removal system for the orbiting frog otolith experiment. [ion exchange resins for water treatment during space missions

    Science.gov (United States)

    Schulz, J. R.; Anselmi, R. T.

    1976-01-01

    The feasibility of using free urease enzyme and ANGC-101 ion exchange resin to remove urea and ammonium ion for space system waste water applications was studied. Specifically examined is the prevention of urea and ammonia toxicity in a 30-day Orbiting Frog Otolith (OFO) flight experiment. It is shown that free urease enzyme used in conjunction with ANGC-101 ion-exchange resin and pH control can control urea and amonium ion concentration in unbuffered recirculating water. In addition, the resin does not adversely effect the bullfrogs by lowering the concentration of cations below critical minimum levels. Further investigations on bioburden control, frog waste excretion on an OFO diet, a trade-off analysis of methods of automating the urea/ammonium ion removal system and fabrication and test of a semiautomated breadboard were recommended as continuing efforts. Photographs of test equipment and test animals are shown.

  13. FUNCTION-MORPHOLOGICAL Investigations of Fish Inner Ear Otoliths as Basis for Interpretation of Human Space Sickness

    Science.gov (United States)

    Edelmann, Elke

    2002-02-01

    In man, altered gravity may lead to a vestibular dysfunction causing space motion sickness. A hypothesis was developed, according to which asymmetric inner ear statoliths might be the morphological basis of space sickness. The animal model, fish, revealed further information: inner ear "stone" (otolith) growth is dependent on the amplitude and the direction of gravity, regulated by a negative feedback mechanism. The present study was focused on the question, where the regulation centre of adaptive otolith growth may be situated. Therefore, the vestibular nerve was unilaterally transected in neonate swordtail fish ( Xiphophorus helleri). As growth marker, the calcium tracer alizarin-complexone was used. It was found that otolith growth had ceased on the operated head sides indicating that the brain is significantly involved in regulating otolith growth. About 2 weeks after nerve transection, otoliths had regained normal growth, probably due to nerve regeneration. Concerning fish, it has now to be tested, if this regeneration is affected by altered gravity, e.g. in a long-term experiment on the International Space Station. Regarding mammals, it has to be proved if asymmetric statoliths are the basis of kinetosis and whether or not the mammalian brain has an effect on statolith growth in the course of compensating altered gravity.

  14. Using otolith weight to predict the age of Pennahia macrocephalus in the mouth of the Beibu Gulf

    Science.gov (United States)

    Yan, Yunrong; Wu, Yanfang; Lu, Huosheng; Li, Zhonglu; Jin, Xianshi

    2009-05-01

    The relation between otolith weight (OW) and the age of marine fish is studied. A total of 222 individuals of bighead white croaker, Pennahia macrocephalus were sampled seasonally in the mouth of the Beibu Gulf, the South China Sea, in 2007. Since there are no significant differences in sagittal OW between otolith in pairs ( P≥0.05), the undamaged left sagittal otolith is used for age determination. The highest correlations among standard length, OW and fish ages are confirmed by linear, exponential and multinomial regression. Results show that sagittal OW overlaps only occasionally among age groups, and to individuals with similar standard length, the older and slower-growing fish has a heavier otolith because of the continued otolith material deposition. There are differences in sagittal OW among different age groups and significant positive linear relationship with age ( Pclosed to the observed ages by counting annulus on scale. It indicates that the sagittal OW analysis is a useful technique for validating the accuracy of age determination by annuli counts, especially for individuals of similar size. Furthermore, the technique is applied for Pennahia macrocephalus with discussion in this paper.

  15. Defining fish nursery habitats: an application of otolith elemental fingerprinting in Tampa Bay, Florida

    Science.gov (United States)

    Ley, Janet A.; McIvor, Carole C.; Peebles, Ernst B; Rolls, Holly; Cooper, Suzanne T.

    2009-01-01

    Fishing in Tampa Bay enhances the quality of life of the area's residents and visitors. However, people's desire to settle along the Bay's shorelines and tributaries has been detrimental to the very habitat believed to be crucial to prime target fishery species. Common snook (Centropomus undecimalis) and red drum (Sciaenops ocellatus) are part of the suite of estuarine fishes that 1) are economically or ecologically prominent, and 2) have complex life cycles involving movement between open coastal waters and estuarine nursery habitats, including nursery habitats that are located within upstream, low-salinity portions of the Bay?s tidal tributaries. We are using an emerging microchemical technique -- elemental fingerprinting of fish otoliths -- to determine the degree to which specific estuarine locations contribute to adult fished populations in Tampa Bay. In ongoing monitoring surveys, over 1,000 young-of-the-year common snook and red drum have already been collected from selected Tampa Bay tributaries. Using laser ablation-inductively coupled plasma - mass spectrometry (LA-ICP-MS), we are currently processing a subsample of these archived otoliths to identify location-specific fingerprints based on elemental microchemistry. We will then analyze older fish from the local fishery in order to match them to their probable nursery areas, as defined by young-of-the-year otoliths. We expect to find that some particularly favorable nursery locations contribute disproportionately to the fished population. In contrast, other nursery areas may be degraded, or act as 'sinks', thereby decreasing their contribution to the fish population. Habitat managers can direct strategic efforts to protect any nursery locations that are found to be of prime importance in contributing to adult stocks.

  16. Using otolith shape for intraspecific discrimination: the case of gurnards (Scorpaeniformes, Triglidae

    Directory of Open Access Journals (Sweden)

    Stefano Montanini

    2015-11-01

    Full Text Available The sagittal otoliths are sound transducers and play an important role in fish hearing. Triglidae (Teleostei, Scorpaeniformes are known for sound producing ability in agonistic contexts related to territorial defence, reproduction and competitive feeding (Amorim et al., 2004. Chelidonichthys cuculus and C. lucerna show a significant body size-depth relationship and specie-specific feeding strategies with growth. Both juveniles and adults of C. cuculus prey necto-benthic invertebrates while C. lucerna specimens change diet from crustaceans to teleost during growth (Stagioni et al., 2012; Vallisneri et al., 2014; Montanini et al., 2015. The goal of this study was to analyze intraspecific shape variations in sagitta of model species of gurnards. 217 specimens were collected during bottom trawl surveys in Adriatic sea (northeastern Mediterranean. Each left sagitta was removed, cleaned in ultrasounds bath and kept dry. The otolith digital images were processed to calculate five shape indices (aspect ratio, roundness, rectangularity, ellipticity and circularity. Indices were normalised to avoid allometric effects according to Lleonart et al. (2000, than processed by linear discriminant analysis (LDA. The SHAPE program was used to extract the outline and to assess the variability of shapes (EFA method and estimated it through the study of principal component analysis (PCA. Considering the first two discriminant functions, LDA plot showed a clearly separation between juvenile and adults for both species. About EFA, the first 4 principal component discriminated over 80% of variance and significant differences were found at critical size between juveniles and adults for all the components analysed. The allometric trends corresponded to a relative elongation of the sulcus acusticus and an increase of excisura ostii. The combined use of the two external outlines methods should be highly informative for intraspecific discrimination and might be related to

  17. Otolith shape analysis as a tool for stock identification of the southern blue whiting, Micromesistius australis

    Directory of Open Access Journals (Sweden)

    Javier Leguá

    2013-07-01

    Full Text Available The southern blue whiting, Micromesistius australis (Norman, 1937, is an important demersal resource associated with the slope and continental shelf of southern Chile, Argentina and the Malvinas/Falkland Islands. Recent studies have reported schools of adult fish from Atlantic waters migrating along the southern Chilean coast in mid-winter, moving northwards to spawn in August (47°-51°S, and then returning to Atlantic waters, presumably to feed. The migratory pattern suggests the presence of one or more stock units associated with the South American coast. In the present study, "otolith morphometry" is used to determine the stock structure of M. australis based on applications of basic size descriptors (SDs (area, perimeter and otolith size, shape indices (SIs (circularity, squareness, shape factor, roundness, ellipticity, and normalised elliptical Fourier descriptors (NEFDs. Samples were collected during the winter and spring of 2010, during the reproductive period, in the economic zone of southern Chile (36°-57°S, in the Pacific Ocean and around the Falkland Islands economic zone (50°-52°S in the Atlantic Ocean. Analyses were conducted to include the effects of size, sex and age. A stepwise canonical discriminant analysis showed that fish were successfully discriminated with SDs, SIs and NEFDs. In this analysis, 86.4% and 70.1% of the fish were correctly classified as belonging to the Atlantic and Pacific stocks, respectively. A multivariate analysis of variance showed that the mean values of the NEFDs, SDs, and SIs did not vary significantly between sexes within areas (P > 0.05, but varied significantly between the Pacific and Atlantic oceans (P < 0.05. These results highlighted that otolith shape analysis can be a useful tool to evaluate the potential level of mixing in feeding areas where both stocks, the Pacific and Atlantic units, are expected to co-occur.

  18. Natural growth, otolith shape and diet analyses of Odontesthes nigricans Richardson (Atherinopsidae) from southern Patagonia

    Science.gov (United States)

    Lattuca, M. E.; Lozano, I. E.; Brown, D. R.; Renzi, M.; Luizon, C. A.

    2015-12-01

    Age and growth, otolith shape and diet of Odontesthes nigricans were analysed in order to provide an insight into the life history of the species and furthermore, to assess their possible use as a tool for discriminating silverside populations from the South Atlantic Ocean (Punta María) and Beagle Channel waters (Varela Bay). The age and growth analysis was performed by counting daily increments and annual marks in sagittae otoliths. Length-at-age data of individuals <65 mm standard length (SL) were fitted to the Laird-Gompertz model (SLt = 6.22 exp 2.45 [1-exp (-0.02t)]), which provided an excellent description of the pattern of daily growth for O. nigricans juveniles from Varela Bay. The spawning period was also assessed through back-calculation of hatching dates and it extended from November to February. The count of annual marks in larger individuals identified 7 year classes (0+ to 6+) in Varela Bay and 6 year classes (0+ to 5+) in Punta María. The von Bertalanffy growth model explained more than 95% of the growth patterns observed in O. nigricans from Varela Bay (SLt = 245.49 [1 - exp -0.24(t+0.46)]) and Punta María (SLt = 345.09 [1 - exp -0.15(t+0.31)]). Particularly, k and SL∞ varied significantly between sampling sites; reaching Punta María a larger SL∞ value with a lower k. Otolith shape variation was also explored using elliptical Fourier analysis and it showed significant differences between Varela Bay and Punta María populations. Furthermore, gut content analysis characterized O. nigricans as an invertebrate predator, being benthic organisms the most important components of its diet, which also showed significant site dependence. The use of all these analyses contributed to a holistic approach which maximized the likelihood of correctly identifying both O. nigricans populations in the southernmost limit of the species distribution.

  19. The use of otolith microstructure to estimate age in adult Atlantic cod Gadus morhua

    DEFF Research Database (Denmark)

    Hüssy, Karin; Hinrichsen, H.H.; Fey, D.P.

    2010-01-01

    primordium of the otolith. Increment formation apparently ceased at temperatures cold months corresponded closely with estimated growth rates. The increment patterns seemed to reflect annual cycles in environmental temperature, and the count of the increment cycles may thus...... to be tightly coupled to the annual cycle in environmental temperature at a depth of 30–60 m, where G. morhua predominantly reside. Between 135 and 200 increments occurred within the different zones, with a non-significant trend towards lower increment numbers and widths with distance from the primary...

  20. Modelling the mixing of herring stocks between the Baltic and the North Sea from otolith data

    DEFF Research Database (Denmark)

    Ulrich, Clara; Post, Søren Lorentzen; Worsøe Clausen, Lotte

    2012-01-01

    Herring catches in the western Baltic, Kattegat and Skagerrak consist of a mixture of stocks, mainly North Sea autumn spawners (NSAS) and western Baltic spring spawners (WBSS), which is managed through a single TAC. Catches of these two stocks are split using otolith microstructures from Danish...... and are consistent with existing ideas about the migration patterns of WBSS and NSAS within Division IIIa and adjacent waters. This work therefore provides the foundation for the development of a more rational management of the herring stocks in this area...

  1. Strontium isotopes in otoliths of a non-migratory fish (slimy sculpin): Implications for provenance studies

    Science.gov (United States)

    Brennan, Sean R.; Fernandez, Diego P.; Zimmerman, Christian E.; Cerling, Thure E.; Brown, Randy J.; Wooller, Matthew J.

    2015-01-01

    Heterogeneity in 87Sr/86Sr ratios of river-dissolved strontium (Sr) across geologically diverse environments provides a useful tool for investigating provenance, connectivity and movement patterns of various organisms and materials. Evaluation of site-specific 87Sr/86Sr temporal variability throughout study regions is a prerequisite for provenance research, but the dynamics driving temporal variability are generally system-dependent and not accurately predictable. We used the time-keeping properties of otoliths from non-migratory slimy sculpin (Cottus cognatus) to evaluate multi-scale 87Sr/86Sr temporal variability of river waters throughout the Nushagak River, a large (34,700 km2) remote watershed in Alaska, USA. Slimy sculpin otoliths incorporated site-specific temporal variation at sub-annual resolution and were able to record on the order of 0.0001 changes in the 87Sr/86Sr ratio. 87Sr/86Sr profiles of slimy sculpin collected in tributaries and main-stem channels of the upper watershed indicated that these regions were temporally stable, whereas the Lower Nushagak River exhibited some spatio-teporal variability. This study illustrates how the behavioral ecology of a non-migratory organism can be used to evaluate sub-annual 87Sr/86Sr temporal variability and has broad implications for provenance studies employing this tracer.

  2. Connectivity between migrating and landlocked populations of a diadromous fish species investigated using otolith microchemistry.

    Directory of Open Access Journals (Sweden)

    Ingrid Tulp

    Full Text Available Smelt Osmerus eperlanus has two different life history strategies in The Netherlands. The migrating population inhabits the Wadden Sea and spawns in freshwater areas. After the closure of the Afsluitdijk in 1932, part of the smelt population became landlocked. The fresh water smelt population has been in severe decline since 1990, and has strongly negatively impacted the numbers of piscivorous water birds relying on smelt as their main prey. The lakes that were formed after the dike closure, IJsselmeer and Markermeer have been assigned as Natura 2000 sites, based on their importance for (among others piscivorous water birds. Because of the declining fresh water smelt population, the question arose whether this population is still supported by the diadromous population. Opportunities for exchange between fresh water and the sea are however limited to discharge sluices. The relationship between the diadromous and landlocked smelt population was analysed by means of otolith microchemistry. Our interpretation of otolith strontium ((88Sr patterns from smelt specimens collected in the fresh water area of Lake IJsselmeer and Markermeer, compared to those collected in the nearby marine environment, is that there is currently no evidence for a substantial contribution from the diadromous population to the spawning stock of the landlocked population.

  3. Otolith shape analysis and mitochondrial DNA markers distinguish three sand smelt species in the Atherina boyeri species complex in western Mediterranean

    Science.gov (United States)

    Boudinar, A. S.; Chaoui, L.; Quignard, J. P.; Aurelle, D.; Kara, M. H.

    2016-12-01

    Atherina boyeri is a common euryhaline teleost fish in the Mediterranean and adjacent areas, which inhabits coastal and estuarine waters, including coastal lagoons and more rarely inland waters. Several recent studies have pointed the possible existence of three distinct groups or species, one lagoon/freshwater group and two 'punctuated and unpunctuated on the flanks' marine groups, within an A. boyeri species complex. This study is a combined approach using otolith shape and molecular markers to better define the structure of the species in the western Mediterranean. Genetic differentiation and species delimitation among nine Atherina boyeri populations from several marine and lagoon/brakish habitat sites in Algeria, Tunisia and France were investigated using three mitochondrial (control region, Cyt b and 16S) and one nuclear markers (2nd intron of S7). For further phylogenetic and phylogeographic study, we added sequences from Genbank covering more areas (Ionian Sea, Adriatic Sea, Tyrrhenian Sea, Black Sea, Atlantic). Five groups were found. Two of them perfectly corresponded to two species already recognized Atherina presbyter and Atherina hepsetus, both living in marine waters; and three additional, including Atherina boyeri (brackish and freshwater environments) and two independent groups of marine punctated and unpunctated individuals. Those findings are corroborated by the study of the otolith contour shape of 362 individuals of seven populations from different habitats using Fourier analysis. Individuals could be discriminated into five groups based on the first two functions (Wilk's lambda = 0.07, p < 0.001). Samples from Ziama inlet, marine punctuated individuals and unpunctuated marine specimens from Annaba's Gulf formed three well separated groups. Specimens from Mellah and Mauguio lagoons formed another group. The last one includes individuals from Bizerte and Thau lagoons. The divergences between them strongly support the potential species within the

  4. FLUCTUATING ASYMMETRY IN THE OTOLITH WIDTH AND LENGTH OF ADULT TELEOST (Beryx splendens LOWE, 1834 (FAMILY: BERCIDAE COLLECTED FROM THE ARABIAN SEA COASTS OF SULTANATE OF OMAN

    Directory of Open Access Journals (Sweden)

    H.K. Albusaidi

    2010-10-01

    Full Text Available Fluctuating asymmetry was described for the otolith width and length of adult teleost Beryx splendens. The results showed that the level of asymmetry of the otolith width was the highest among the two asymmetry values obtained for the otolith of B. splendens. For the otolith width character, the results showed that the level of asymmetry at its highest value in fish ranging in length between 191–200 mm and in its lowest value in fish ranging in length between 121–180 mm. For the otolith length, the highest value of asymmetry is noticed in fish ranging in length between 231–244 mm and the lowest value in fish within the length of 121–190 mm. The possible cause of the asymmetry in this species has been discussed in relation to different pollutants and their presence in the area. No trend of increase in the asymmetry values with the fish length was noticed for the otolith width, but there is a weak trend of increase with the fish length in case of otolith length character.

  5. [Clinical research of the otolith abnormal migration during canalith repositioning procedures for posterior semicircular canal benign paroxysmal positional vertigo].

    Science.gov (United States)

    Ou, Yongkang; Zheng, Yiging; Zhu, Honglei; Chen, Ling; Zhong, Junwei; Tang, Xiaowu; Huang, Qiuhong; Xu, Yaodong

    2015-01-01

    To investigate the risk factor,type and characteristic nystagmus of the otolith abnormal migration during diagnosis and treatment for posterior semicircular canal benign paroxysmal positional vertigo (PSC-BPPV). The therapy and prevention is also discussed. Four hundred and seventy-nine patients with PSC-BPPV were treated by Epley's canalith repositioning procedures(CRP) from March 2009 to March 2012. We observed otolith abnormal migration complicating during diagnosis and treatment. According the type of otolith abnormal migration, the additional repositioning maneuver was performed. The rate of complication was 8. 1%(39/479), with canal conversion in 5.4%(26/479) and primarily canal reentry in 2.7%(13/479). The rate of incidence of conversion to horizontal canal conversion and anterior canal were 4. 8%(23/479)and 0. 6%(3/479) respectively. All the patient was cured in follow up. The risk factors were unappropriated head movement during or after CRP, including another Dix-Hallpike were performed immediately. To prevent the complications,the pathognostic positioning sequence and angle of head rotation are commenced during CRP. Appropriate short time postural restrictions post-treatment is necessary. Careful observation of nystagrnus variation is crucial to determine the otolith abnormal migration.

  6. Plasma membrane calcium ATPase required for semicircular canal formation and otolith growth in the zebrafish inner ear.

    Science.gov (United States)

    Cruz, Shelly; Shiao, Jen-Chieh; Liao, Bo-Kai; Huang, Chang-Jen; Hwang, Pung-Pung

    2009-03-01

    Fish otoliths consist of >90% calcium carbonate, the accretion of which depends on acellular endolymph. This study confirms the presence of plasma membrane calcium ATPase 1a isoform (Atp2b1a) in the auditory and vestibular system of a teleost fish. As shown by in situ hybridization, zebrafish atp2b1a is expressed mainly in larval otic placode and lateral-line neuromast as well as in the hair cells within the adult zebrafish inner ear chamber. Zebrafish atp2b1a knockdown by antisense morpholinos reduced the number of hair cells and produced malformation of semicircular canals and smaller otoliths. These defects coincide with unbalanced body orientation. The formation of smaller otoliths in atp2b1a morphants may stem from an impairment of calcium supply in the endolymph. However, otolith formation persists in most morphants, suggesting that other zebrafish Atp2b isoforms or paracellular pathways may also transport calcium into the endolymph. These results suggest that Atp2b1a plays an important role for normal development of the auditory and vestibular system as well as calcium transport in the inner ear of zebrafish.

  7. Reconstructing Age Distribution, Season of Capture and Growth Rate of Fish from Archaeological Sites Based on Otoliths and Vertebrae

    NARCIS (Netherlands)

    Neer, van W.; Lougas, L.; Rijnsdorp, A.D.

    1999-01-01

    The growth increments of otoliths and vertebrae of plaice (Pleuronectes platessa) derived from a 15th century single depositional event at Raversijde (Belgium) are analysed with the aim of reconstructing (a) the age distribution of the population, (b) the season of capture, and (c) the growth rate.

  8. A novel length back-calculation approach accounting for ontogenetic changes in the fish length - otolith size relationship during the early life of sprat (Sprattus sprattus)

    DEFF Research Database (Denmark)

    Guenther, Claudia C.; Temming, Axel; Baumann, Hannes

    2012-01-01

    An individual-based length back-calculation method was developed for juvenile Baltic sprat (Sprattus sprattus), accounting for ontogenetic changes in the relationship between fish length and otolith length. In sprat, metamorphosis from larvae to juveniles is characterized by the coincidence of low...... length growth, strong growth in body height, and maximal otolith growth. Consequently, the method identifies a point of metamorphosis for an individual as the otolith radius at maximum increment widths. By incorporating this information in our back-calculation method, estimated length growth...

  9. A millennium of north-east Atlantic cod juvenile growth trajectories inferred from archaeological otoliths.

    Directory of Open Access Journals (Sweden)

    Guðbjörg Ásta Ólafsdóttir

    Full Text Available Archaeological excavations of historical fishing sites across the North Atlantic have recovered high quantities of Atlantic cod (Gadus morhua bones. In the current study we use Atlantic cod otoliths from archaeological excavations of a historical fishing sites in north-west Iceland, dated to AD 970 -AD 1910 to examine historical growth trajectories of cod. No large scale growth variations or shifts in growth patterns were observed in the current chronologies, supporting the stability of historical Atlantic cod growth trajectories. The most significant variation in growth patterns was consistent with those that have been observed in recent times, for example, reduced early juvenile growth during periods of colder ocean temperature. The current results represent a high resolution chronological record of north-east Atlantic cod growth, greatly increasing the prior temporal range of such data, thereby providing a valuable baseline for a broad range of studies on Atlantic cod growth.

  10. Evaluation of chemical markers for age validation of western Baltic cod (Gadus morhua otoliths

    Directory of Open Access Journals (Sweden)

    Sven Stötera

    2015-11-01

    Baltic cod were intraperitoneally injected with the different chemicals and kept for 47 days in netpens. The lowest mortality and best ring formation was observed at 100mg/kg cod wet weight compared to 50 and 25mg/kg wet weight (TET only. Preliminary analysis suggests that the simultaneous injection of TET and STR decreases the visibility of TET-rings. This is probably due to a binding interaction between both markers in the body of the fish, so that less TET is bound in the otolith. The use of tetracycline hydrochloride in the concentrations of 50 mg/kg and 100 mg/kg fish were considered the most appropriate to mark Baltic cod for age validation in large-scale mark-recapture experiments. TET and STR should not be injected together.

  11. A millennium of north-east Atlantic cod juvenile growth trajectories inferred from archaeological otoliths.

    Science.gov (United States)

    Ólafsdóttir, Guðbjörg Ásta; Pétursdóttir, Gróa; Bárðarson, Hlynur; Edvardsson, Ragnar

    2017-01-01

    Archaeological excavations of historical fishing sites across the North Atlantic have recovered high quantities of Atlantic cod (Gadus morhua) bones. In the current study we use Atlantic cod otoliths from archaeological excavations of a historical fishing sites in north-west Iceland, dated to AD 970 -AD 1910 to examine historical growth trajectories of cod. No large scale growth variations or shifts in growth patterns were observed in the current chronologies, supporting the stability of historical Atlantic cod growth trajectories. The most significant variation in growth patterns was consistent with those that have been observed in recent times, for example, reduced early juvenile growth during periods of colder ocean temperature. The current results represent a high resolution chronological record of north-east Atlantic cod growth, greatly increasing the prior temporal range of such data, thereby providing a valuable baseline for a broad range of studies on Atlantic cod growth.

  12. The Otolith Group’s “Monuments to Dead Television.” Independent Cinema and the Migrant Experience in Europe between Television and the Museum

    National Research Council Canada - National Science Library

    Ferrara, Beatrice

    2014-01-01

    “Monument to dead television” is the expression the British collective The Otolith Group uses to define its activity of recuperating long-lost quality films, and re-screening them in contemporary art museums and gallery spaces...

  13. [Otolith function tests--a differentiated, quality-assured screening system].

    Science.gov (United States)

    Düwel, P; Walther, L E; Sanders, M; Ilgner, J; Westhofen, M

    2005-09-01

    More than 30% of all otogenic vestibular disorders are related to isolated macular dysfunction. Videooculographic examination techniques for the otolith-ocular reflex, e. g. by means of eccentric rotation tests, are not widely used in clinical routine as these put a considerable strain on technical and staff resources. Thus, there is a considerable risk of "false negative" classification of vertigo disorders being labelled as "non-otogenic". By means of vestibular-evoked myogenic potentials (VEMPs) and caloric irrigation in prone and supine position, several examination techniques for a side-related investigation of macula-induced vestibulo-ocular reflexes are available. The objective of this study is to compare and evaluate these techniques as screening tests. In 32 patients with vestibular disorders we performed investigations for VEMPs, eccentric rotation tests, as well as caloric irrigation for macular reaction in prone and supine position. In addition, we performed other audiologic and vestibular function tests which were complemented by the clinical course in order to differentiate each case between otogenic and non-otogenic vertigo with or without macular affection. The technical feasibility as well as patients' acceptance for VEMP testing is better than for eccentric rotation tests. The sensitivity index for VEMPs (89%) as well as for caloric irrigation in prone and supine position for macular examination (71%) is satisfactory. However, the specificity of VEMPs is inferior (53%) to eccentric rotation (100%). Both the examination for VEMPs as well as caloric macular testing in prone and supine position carry features which make them feasible for screening, even though these two procedures test for two different parts of the otolith system. However, to confirm a diagnosis and to set up a therapeutic concept for macular function disorders, eccentric rotation should be added.

  14. The co-effect of organic matrix from carp otolith and microenvironment on calcium carbonate mineralization.

    Science.gov (United States)

    Ren, Dongni; Feng, Qingling; Bourrat, Xavier

    2013-08-01

    In vitro mineralization experiment is an effective way to study the effect of organic matrix on calcium carbonate crystallization, and to reveal the relationship between organic matrix and inorganic crystal in natural biominerals. In natural biominerals, organic matrix plays an important role in crystal formation and stability, together with microenvironment changes, they can affect crystal polymorph, morphology, density, size, orientation etc. In this work, we systematically studied the effects of different organic matrices in fish otoliths, the organic matrix concentration changes, as well as the co-effect of organic matrices with temperature, pH value and Mg ion changes in the in vitro CaCO3 mineralization experiments. The organic matrix and concentration change experiments prove that water soluble matrix (WSM) plays an important role in crystal form transition. It can induce CaCO3 crystals with same crystal polymorph as the otolith from which organic matrix was extracted. The temperature change experiment proves that CaCO3 has a tendency to form calcite, vaterite, and then aragonite in priority as temperature goes up. Under different temperature, WSM from lapillus/asteriscus still has the effect to mediate different CaCO3 crystals. The pH change experiment shows that, near the neutral environment, as pH value goes up, calcites have a tendency to form crystal aggregates with more faces exposed, the organic matrix still keeps crystal mediation effect. The Mg(2+) experiment shows that, Mg ion can promote aragonite formation, together with lapillus organic matrix, aragonites with different shapes are formed. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. Fine-scale oscillatory banding in otoliths from arctic charr (Salveninus alpinus) and pike (Esox lucius)

    Energy Technology Data Exchange (ETDEWEB)

    Meldrum, A. [Oak Ridge National Lab., TN (United States); Halden, N.M. [Univ. of Manitoba, Winnipeg (Canada). Dept. of Geological Sciences

    1997-12-31

    Transmission electron microscopy of otoliths from the inner ear of arctic charr and pike has revealed the presence of fine banding on the scale of several nanometers. The thickness of the bands was observed to vary in different portions of the sample, and some areas were not banded. EDS analysis could not detect chemical differences within the bands, but electron diffraction showed that the crystallographic orientation of the bands is related by a lattice mismatch. Previously, banding on the scale of 50 to 100 microns was observed by SEM in otoliths from arctic charr and was attributed to seasonal variations in growth. The fine-scale banding observed in this study, however, is unlikely to represent a daily variation. Electron diffraction from the pike samples shows that the material is composed of CaCO{sub 3} having the both the vaterite and aragonite structure, and hydrous CaCO{sub 3} was also observed. The large-scale banding previously identified by SEM was not observed in the TEM despite attempts to intersect the boundaries of the micron-sized layers. The interaction of the electron beam with the sample material was investigated by conducting several electron-irradiation experiments. The electron beam was observed to interact strongly with the sample and caused the precipitation of cubic CaO from the calcium carbonate matrix. Bright-field imaging showed the development of fine grained ({approximately} 5 nm) randomly oriented crystallites which accumulated with increasing electron dose. These initial results suggest that the precipitation of CaO is not driven by electron-beam beating. Previously, a similar phase-change phenomenon has been observed in hydroxyapatite from dental enamel. Other Ca-bearing biominerals may therefore also be expected to be sensitive to electron irradiation.

  16. Fully-automated identification of fish species based on otolith contour: using short-time Fourier transform and discriminant analysis (STFT-DA).

    Science.gov (United States)

    Salimi, Nima; Loh, Kar Hoe; Kaur Dhillon, Sarinder; Chong, Ving Ching

    2016-01-01

    Background. Fish species may be identified based on their unique otolith shape or contour. Several pattern recognition methods have been proposed to classify fish species through morphological features of the otolith contours. However, there has been no fully-automated species identification model with the accuracy higher than 80%. The purpose of the current study is to develop a fully-automated model, based on the otolith contours, to identify the fish species with the high classification accuracy. Methods. Images of the right sagittal otoliths of 14 fish species from three families namely Sciaenidae, Ariidae, and Engraulidae were used to develop the proposed identification model. Short-time Fourier transform (STFT) was used, for the first time in the area of otolith shape analysis, to extract important features of the otolith contours. Discriminant Analysis (DA), as a classification technique, was used to train and test the model based on the extracted features. Results. Performance of the model was demonstrated using species from three families separately, as well as all species combined. Overall classification accuracy of the model was greater than 90% for all cases. In addition, effects of STFT variables on the performance of the identification model were explored in this study. Conclusions. Short-time Fourier transform could determine important features of the otolith outlines. The fully-automated model proposed in this study (STFT-DA) could predict species of an unknown specimen with acceptable identification accuracy. The model codes can be accessed at http://mybiodiversityontologies.um.edu.my/Otolith/ and https://peerj.com/preprints/1517/. The current model has flexibility to be used for more species and families in future studies.

  17. Fully-automated identification of fish species based on otolith contour: using short-time Fourier transform and discriminant analysis (STFT-DA

    Directory of Open Access Journals (Sweden)

    Nima Salimi

    2016-02-01

    Full Text Available Background. Fish species may be identified based on their unique otolith shape or contour. Several pattern recognition methods have been proposed to classify fish species through morphological features of the otolith contours. However, there has been no fully-automated species identification model with the accuracy higher than 80%. The purpose of the current study is to develop a fully-automated model, based on the otolith contours, to identify the fish species with the high classification accuracy. Methods. Images of the right sagittal otoliths of 14 fish species from three families namely Sciaenidae, Ariidae, and Engraulidae were used to develop the proposed identification model. Short-time Fourier transform (STFT was used, for the first time in the area of otolith shape analysis, to extract important features of the otolith contours. Discriminant Analysis (DA, as a classification technique, was used to train and test the model based on the extracted features. Results. Performance of the model was demonstrated using species from three families separately, as well as all species combined. Overall classification accuracy of the model was greater than 90% for all cases. In addition, effects of STFT variables on the performance of the identification model were explored in this study. Conclusions. Short-time Fourier transform could determine important features of the otolith outlines. The fully-automated model proposed in this study (STFT-DA could predict species of an unknown specimen with acceptable identification accuracy. The model codes can be accessed at http://mybiodiversityontologies.um.edu.my/Otolith/ and https://peerj.com/preprints/1517/. The current model has flexibility to be used for more species and families in future studies.

  18. Oxygen isotopic distribution along the otolith growth axis by secondary ion mass spectrometry: Applications for studying ontogenetic change in the depth inhabited by deep-sea fishes

    Science.gov (United States)

    Shiao, Jen-Chieh; Itoh, Shoichi; Yurimoto, Hisayoshi; Iizuka, Yoshiyuki; Liao, Yun-Chih

    2014-02-01

    This study using tuna otoliths as working standards established a high lateral resolution and precision analysis to measure δ18Ootolith by secondary ion mass spectrometry. This analytical approach of the ion probe was applied to deep-sea fishes to reconstruct the likely depths inhabited by the fishes at different life history stages based on the measured δ18Ootolith values as a proxy of water temperature. Dramatic increases up to 5-6‰ in δ18Ootolith, representing a temperature decrease of approximately 20 °C, were detected in a blind cusk eel (Barathronus maculatus) otolith and in the otoliths of Synaphobranchus kaupii during leptocephalus metamorphosis to glass eel, inferred from the drop of otolith Sr/Ca ratios and increase of otolith growth increment width. δ18Ootolith profiles clearly divided the fish's life history into a planktonic stage in the mixed layer of the ocean and a benthic stage on the deep-sea ocean bottom. The habitat shift signal was recorded within a 150 μm width of otolith growth zone, which was too narrow to be clearly detected by mechanical drilling and conventional isotopic ratio mass spectrometry. However, variations down to -7‰ were found in δ18Ootolith profiles as the result of Cs2+ beam sputter in the core and larval portions of the otoliths. Carbon mapping by electron probe microanalyzer and staining by toluidine blue suggested abundant proteins existed in the areas with anomaly negative δ18Ootolith values, which cannot be interpreted as a habitat change but due to the isotopic fractionation by O emission from the proteins. These results implied that careful design and understanding of the chemical composition of the analytical areas or tracks on the heterogeneous otolith was essential for highly accurate and precise analysis.

  19. Fingerprints of lagoonal life: Migration of the marine flatfish Solea solea assessed by stable isotopes and otolith microchemistry

    Science.gov (United States)

    Dierking, Jan; Morat, Fabien; Letourneur, Yves; Harmelin-Vivien, Mireille

    2012-06-01

    The commercially important marine flatfish common sole (Solea solea) facultatively uses NW Mediterranean lagoons as nurseries. To assess the imprint left by the lagoonal passage, muscle carbon (C) and nitrogen (N) isotope values of S. solea juveniles caught in Mauguio lagoon in spring (shortly after arrival from the sea) and in autumn (before the return to the sea) were compared with values of juveniles from adjacent coastal marine nurseries. In addition, in the lagoon, sole otolith stable isotope (C and oxygen (O)) and elemental (11 elements) composition in spring and autumn, and the stable isotope composition (C and N) of organic matter sources in autumn, were determined. Overall, our data indicate that a distinct lagoonal signature existed. Specifically, lagoon soles showed a strong enrichment in muscle tissue 15N (>6‰) compared to their coastal relatives, likely linked to sewage inputs (see below), and a depletion in 13C (1-2‰), indicative of higher importance of 13C depleted terrestrial POM in the lagoon compared to coastal nurseries. In addition, over the time spent in the lagoon, sole otolith δ13C and δ18O values and otolith elemental composition changed significantly. Analysis of the lagoon sole foodweb based on C and N isotopes placed sediment particulate organic matter (POM) at the base. Seagrasses, formerly common but in decline in Mauguio lagoon, played a minor role in the detritus cycle. The very strong 15N enrichment of the entire foodweb (+7 to +11‰) compared to little impacted lagoons and coastal areas testified of important human sewage inputs. Regarding the S. solea migration, the analysis of higher turnover and fast growth muscle tissue and metabolically inert and slower growth otoliths indicated that soles arrived at least several weeks prior to capture in spring, and that no migrations took place in summer. In the autumn, the high muscle δ15N value acquired in Mauguio lagoon would be a good marker of recent return to the sea, whereas

  20. Age, growth and utility of otolith morphometrics as a predictor of age in the wrasse Coris julis (Labridae from the eastern Adriatic Sea

    Directory of Open Access Journals (Sweden)

    Frane Škeljo

    2012-09-01

    Full Text Available Age and growth of Coris julis were determined by examining sagittal otoliths belonging to fish sampled between November 2008 and October 2009 in the eastern Adriatic Sea (north-central Mediterranean Sea. A total of 1102 specimens (528 males, 487 females and 87 individuals of indeterminate sex, ranging from 48 to 222 mm total length were analysed. Ninety-two per cent of the otoliths were readable and 68% of the specimens had two readings in agreement. Counting of daily rings revealed that the second opaque ring represents the first annulus (315.1±27.8 daily rings. The maximum observed age was 7 years for males and 5 years for females, with males dominating in higher age classes ( > 3 years and females in age classes 1+ and 2+. Growth was described by the von Bertalanffy growth curves and significant differences were found between males (L∞=29.10 cm, k=0.12 and t0=–1.48 and females (L∞=21.27 cm, k=0.21 and t0=–1.08. Otolith mass, length, width and thickness were determined for the otoliths belonging to 465 fish and the utility of these morphometrics as a predictor of age was evaluated. The most precise age estimations were obtained from the otolith length data, followed by the otolith mass.

  1. Precision and accuracy of age estimates obtained from anal fin spines, dorsal fin spines, and sagittal otoliths for known-age largemouth bass

    Science.gov (United States)

    Klein, Zachary B.; Bonvechio, Timothy F.; Bowen, Bryant R.; Quist, Michael C.

    2017-01-01

    Sagittal otoliths are the preferred aging structure for Micropterus spp. (black basses) in North America because of the accurate and precise results produced. Typically, fisheries managers are hesitant to use lethal aging techniques (e.g., otoliths) to age rare species, trophy-size fish, or when sampling in small impoundments where populations are small. Therefore, we sought to evaluate the precision and accuracy of 2 non-lethal aging structures (i.e., anal fin spines, dorsal fin spines) in comparison to that of sagittal otoliths from known-age Micropterus salmoides (Largemouth Bass; n = 87) collected from the Ocmulgee Public Fishing Area, GA. Sagittal otoliths exhibited the highest concordance with true ages of all structures evaluated (coefficient of variation = 1.2; percent agreement = 91.9). Similarly, the low coefficient of variation (0.0) and high between-reader agreement (100%) indicate that age estimates obtained from sagittal otoliths were the most precise. Relatively high agreement between readers for anal fin spines (84%) and dorsal fin spines (81%) suggested the structures were relatively precise. However, age estimates from anal fin spines and dorsal fin spines exhibited low concordance with true ages. Although use of sagittal otoliths is a lethal technique, this method will likely remain the standard for aging Largemouth Bass and other similar black bass species.

  2. Méthodologies à rayons X micro-focalisés pour l'étude biogéochimique d’otolithes archéologiques et modernes

    OpenAIRE

    Cook, Phil K.

    2015-01-01

    Otoliths, aragonitic growths in the inner ear of teleost fishes, can be used as proxies for the water conditions experienced by an individual over its lifetime. A set of archaeological Sciaenidae and Ariidae otoliths and modern counterparts was studied with the objective of improving palaeoenvironmental reconstruction methodologies using otoliths and other incremental carbonate biominerals. The incorporation of strontium, the most accessible environment-related element, was studied by X-ray a...

  3. Slave to the rhythm: seasonal signals in otolith microchemistry reveal age of eastern Baltic cod (Gadus morhua)

    DEFF Research Database (Denmark)

    Hüssy, Karin; Gröger, J.; Heidemann, F.

    2016-01-01

    Annual growth zones in cod otoliths from the eastern Baltic stock are less discrete than in other cod stocks leading to biased age reading, which recently led to a failure of age-based assessment in the eastern Baltic cod stock. In this study, we explored the applicability of minor and trace...... element patterns in cod otoliths for age determination. By first identifying elements of interest in a stock without ageing problems, western Baltic cod, we then tested their applicability on another stock without ageing problems, North Sea cod, and finally applied this knowledge to estimate age...... significance of the local profile minima were identified, based on which their age could be estimated. Despite extensive environmental differences between the three areas examined, the element concentrations of Cu, Zn, and Rb were strongly correlated in all individuals with similar correlations in all three...

  4. Coupling otolith microstructure analysis and hydrographic backtracking suggests a mechanism for the 2000s North Sea herring recruitment failure

    DEFF Research Database (Denmark)

    Ross, Stine Dalmann; Payne, Mark; Worsøe Clausen, Lotte

    2012-01-01

    , associated with the onset of the reduced recruitment, was identified. These results suggest that the reduced recruitment is associated with a reduction in the growth rate of the larval survivors, most probably through changes in either the amount or quality of the available food. Furthermore, this study......The North Sea autumn spawning herring (Clupea harengus) has, since the 2002 year class, shown an unprecedented sequence of ten years of sharply reduced recruitment, in spite of a high spawning biomass and low fishing mortality. Recent work has identified this reduction in recruitment level (or....... Individual larval growth rates, averaged over the 30 days prior to capture, were estimated for 200 larval otoliths from four different years using a model‐based analysis of the ring widths. The otolith measurements were complemented with additional information derived from hydrographic backtracking models (e...

  5. Of travertine and time: otolith chemistry and microstructure detect provenance and demography of endangered humpback chub in Grand Canyon, USA.

    Science.gov (United States)

    Limburg, Karin E; Hayden, Todd A; Pine, William E; Yard, Michael D; Kozdon, Reinhard; Valley, John W

    2013-01-01

    We developed a geochemical atlas of the Colorado River in Grand Canyon and in its tributary, the Little Colorado River, and used it to identify provenance and habitat use by Federally Endangered humpback chub, Gila cypha. Carbon stable isotope ratios (δ(13)C) discriminate best between the two rivers, but fine scale analysis in otoliths requires rare, expensive instrumentation. We therefore correlated other tracers (SrSr, Ba, and Se in ratio to Ca) to δ(13)C that are easier to quantify in otoliths with other microchemical techniques. Although the Little Colorado River's water chemistry varies with major storm events, at base flow or near base flow (conditions occurring 84% of the time in our study) its chemistry differs sufficiently from the mainstem to discriminate one from the other. Additionally, when fish egress from the natal Little Colorado River to the mainstem, they encounter cold water which causes the otolith daily growth increments to decrease in size markedly. Combining otolith growth increment analysis and microchemistry permitted estimation of size and age at first egress; size at first birthday was also estimated. Emigrants < 1 year old averaged 51.2 ± 4.4 (SE) days and 35.5 ± 3.6 mm at egress; older fish that had recruited to the population averaged 100 ± 7.8 days old and 51.0 ± 2.2 mm at egress, suggesting that larger, older emigrants recruit better. Back-calculated size at age 1 was unimodal and large (78.2 ± 3.3 mm) in Little Colorado caught fish but was bimodally distributed in Colorado mainstem caught fish (49.9 ± 3.6 and 79 ± 4.9 mm) suggesting that humpback chub can also rear in the mainstem. The study demonstrates the coupled usage of the two rivers by this fish and highlights the need to consider both rivers when making management decisions for humpback chub recovery.

  6. Of travertine and time: otolith chemistry and microstructure detect provenance and demography of endangered humpback chub in Grand Canyon, USA.

    Directory of Open Access Journals (Sweden)

    Karin E Limburg

    Full Text Available We developed a geochemical atlas of the Colorado River in Grand Canyon and in its tributary, the Little Colorado River, and used it to identify provenance and habitat use by Federally Endangered humpback chub, Gila cypha. Carbon stable isotope ratios (δ(13C discriminate best between the two rivers, but fine scale analysis in otoliths requires rare, expensive instrumentation. We therefore correlated other tracers (SrSr, Ba, and Se in ratio to Ca to δ(13C that are easier to quantify in otoliths with other microchemical techniques. Although the Little Colorado River's water chemistry varies with major storm events, at base flow or near base flow (conditions occurring 84% of the time in our study its chemistry differs sufficiently from the mainstem to discriminate one from the other. Additionally, when fish egress from the natal Little Colorado River to the mainstem, they encounter cold water which causes the otolith daily growth increments to decrease in size markedly. Combining otolith growth increment analysis and microchemistry permitted estimation of size and age at first egress; size at first birthday was also estimated. Emigrants < 1 year old averaged 51.2 ± 4.4 (SE days and 35.5 ± 3.6 mm at egress; older fish that had recruited to the population averaged 100 ± 7.8 days old and 51.0 ± 2.2 mm at egress, suggesting that larger, older emigrants recruit better. Back-calculated size at age 1 was unimodal and large (78.2 ± 3.3 mm in Little Colorado caught fish but was bimodally distributed in Colorado mainstem caught fish (49.9 ± 3.6 and 79 ± 4.9 mm suggesting that humpback chub can also rear in the mainstem. The study demonstrates the coupled usage of the two rivers by this fish and highlights the need to consider both rivers when making management decisions for humpback chub recovery.

  7. Effects of Simulated Microgravity on Otolith Growth of Larval Zebrafish using a Rotating-Wall Vessel: Appropriate Rotation Speed and Fish Developmental Stage

    Science.gov (United States)

    Li, Xiaoyan; Anken, Ralf; Liu, Liyue; Wang, Gaohong; Liu, Yongding

    2017-02-01

    Stimulus dependence is a general feature of developing animal sensory systems. In this respect, it has extensively been shown earlier that fish inner ear otoliths can act as test masses as their growth is strongly affected by altered gravity such as hypergravity obtained using centrifuges, by (real) microgravity achieved during spaceflight or by simulated microgravity using a ground-based facility. Since flight opportunities are scarce, ground-based simulators of microgravity, using a wide variety of physical principles, have been developed to overcome this shortcoming. Not all of them, however, are equally well suited to provide functional weightlessness from the perspective of the biosystem under evaluation. Therefore, the range of applicability of a particular simulator has to be extensively tested. Earlier, we have shown that a Rotating-Wall Vessel (RWV) can be used to provide simulated microgravity for developing Zebrafish regarding the effect of rotation on otolith development. In the present study, we wanted to find the most effective speed of rotation and identify the appropriate developmental stage of Zebrafish, where effects are the largest, in order to provide a methodological basis for future in-depth analyses dedicated to the physiological processes underlying otolith growth at altered gravity. Last not least, we compared data on the effect of simulated microgravity on the size versus the weight of otoliths, since the size usually is measured in related studies due to convenience, but the weight more accurately approximates the physical capacity of an otolith. Maintaining embryos at 10 hours post fertilization for three days in the RWV, we found that 15 revolutions per minute (rpm) yielded the strongest effects on otolith growth. Maintenance of Zebrafish staged at 10 hpf, 1 day post fertilization (dpf), 4 dpf, 7 dpf and 14 dpf for three days at 15 rpm resulted in the most prominent effects in 7 dpf larvae. Weighing versus measuring the size of otoliths

  8. Otolith shape analysis for stock discrimination of two Collichthys genus croaker (Pieces: Sciaenidae,) from the northern Chinese coast

    Science.gov (United States)

    Zhao, Bo; Liu, Jinhu; Song, Junjie; Cao, Liang; Dou, Shuozeng

    2017-08-01

    The otolith morphology of two croaker species (Collichthys lucidus and Collichthys niveatus) from three areas (Liaodong Bay, LD; Huanghe (Yellow) River estuary, HRE; Jiaozhou Bay, JZ) along the northern Chinese coast were investigated for species identification and stock discrimination. The otolith contour shape described by elliptic Fourier coefficients (EFC) were analysed using principal components analysis (PCA) and stepwise canonical discriminant analysis (CDA) to identify species and stocks. The two species were well differentiated, with an overall classification success rate of 97.8%. And variations in the otolith shapes were significant enough to discriminate among the three geographical samples of C. lucidus (67.7%) or C. niveatus (65.2%). Relatively high mis-assignment occurred between the geographically adjacent LD and HRE samples, which implied that individual mixing may exist between the two samples. This study yielded information complementary to that derived from genetic studies and provided information for assessing the stock structure of C. lucidus and C. niveatus in the Bohai Sea and the Yellow Sea.

  9. Age validation of canary rockfish (Sebastes pinniger) using two independent otolith techniques: lead-radium and bomb radiocarbon dating.

    Energy Technology Data Exchange (ETDEWEB)

    Andrews, A H; Kerr, L A; Cailliet, G M; Brown, T A; Lundstrom, C C; Stanley, R D

    2007-11-04

    Canary rockfish (Sebastes pinniger) have long been an important part of recreational and commercial rockfish fishing from southeast Alaska to southern California, but localized stock abundances have declined considerably. Based on age estimates from otoliths and other structures, lifespan estimates vary from about 20 years to over 80 years. For the purpose of monitoring stocks, age composition is routinely estimated by counting growth zones in otoliths; however, age estimation procedures and lifespan estimates remain largely unvalidated. Typical age validation techniques have limited application for canary rockfish because they are deep dwelling and may be long lived. In this study, the unaged otolith of the pair from fish aged at the Department of Fisheries and Oceans Canada was used in one of two age validation techniques: (1) lead-radium dating and (2) bomb radiocarbon ({sup 14}C) dating. Age estimate accuracy and the validity of age estimation procedures were validated based on the results from each technique. Lead-radium dating proved successful in determining a minimum estimate of lifespan was 53 years and provided support for age estimation procedures up to about 50-60 years. These findings were further supported by {Delta}{sup 14}C data, which indicated a minimum estimate of lifespan was 44 {+-} 3 years. Both techniques validate, to differing degrees, age estimation procedures and provide support for inferring that canary rockfish can live more than 80 years.

  10. Use of otolith for detecting strontium-90 in fish from the harbor of Fukushima Dai-ichi Nuclear Power Plant.

    Science.gov (United States)

    Fujimoto, Ken; Miki, Shizuho; Kaeriyama, Hideki; Shigenobu, Yuya; Takagi, Kaori; Ambe, Daisuke; Ono, Tsuneo; Watanabe, Tomowo; Morinaga, Kenji; Nakata, Kaoru; Morita, Takami

    2015-06-16

    To clarify the level of contamination with radioactive cesium (radiocesium) discharged from Fukushima Dai-ichi Nuclear Power Plant (FDNPP), three fish species caught in the main harbor of FDNPP were subjected to γ-ray analysis. The concentration of radiocesium in muscle differed among individual fish, even those of similar size of the same species, and showed little relation to the standard length of fish. The maximum concentration of radiocesium (202 kBq/kg wet) was detected from fat greenling samples. A comparison to data from outside the port indicated that the level of radiocesium contamination inside the port was higher than that outside. We found that β-rays were emitted from otoliths of fishes caught in the port of FDNPP. β-ray intensities were correlated with the concentrations of radiocesium in muscles of the three fish species. In Japanese rockfish, the β-ray count rates from otoliths were significantly correlated with the concentration of radiocesium and (90)Sr in the whole body without internal organs of Japanese rockfish. However, no β-rays were detected from brown hakeling samples collected around FDNPP, suggesting that the detection of β-rays from otoliths may indicate living in the main harbor of FDNPP.

  11. Life history inhomogeneity in Baltic Sea whitefish populations revealed by otolith strontium signatures – identification of stocked fish

    Directory of Open Access Journals (Sweden)

    Henry Hägerstrand

    2015-11-01

    The strontium concentrations in the otolith cores of whitefish from River Tornionjoki were higher than that of the four otoliths with low core strontium from fishes caught at sea (Table 1. Supposing that this latter group represent stocked fish raised in freshwater ponds, the vast majority of River Tornionjoki whitefish is naturally reproduced fish. This is plausible because in River Tornionjoki, the major whitefish spawning river in Finland, no larger stocking have been made since 1990s (Jokikokko and Huhmarniemi 2014. In conclusion, the concentration of otolith core strontium differs in whitefish hatched in fresh-water and in whitefish hatched in river water or in brackish Baltic Sea water. This difference can be used to reveal stocked whitefish. Barium concentration may be an even better indicator in this respect than strontium, as previous results indicate (Hägerstrand et al., 2015. Stocked river spawning whitefish appear in large amount at the southern feeding grounds around the Åland Islands, as already indicated by e.g. Leskelä et al. (2009.

  12. Otolith morphology varies between populations, sexes and male alternative reproductive tactics in a vocal toadfish Porichthys notatus.

    Science.gov (United States)

    Bose, A P H; Adragna, J B; Balshine, S

    2017-01-01

    In this study, the morphology of sagittal otoliths of the plainfin midshipman fish Porichthys notatus was compared between populations, sexes and male alternative reproductive phenotypes (known as 'type I males or guarders' and 'type II males or sneakers'). Sagitta size increased with P. notatus size and changes in shape were also detected with increasing body size. Porichthys notatus sagittae begin as simple rounded structures, but then elongate as they grow and take on a more triangular and complex shape with several prominent notches and indentations along the dorsal and caudal edges. Moreover, the sagittae of the two geographically and genetically distinct populations of P. notatus (northern and southern) differed in shape. Porichthys notatus from the north possessed taller sagittae with deeper caudal indentations compared to P. notatus from the south. Sagitta shape also differed between females and males of the conventional guarder tactic. Furthermore, guarder males had smaller sagittae for their body size than did sneaker males or females. These differences in sagittal otolith morphology are discussed in relation to ecological and life history differences between the sexes and male tactics of this species. This is the first study to investigate teleost otolith morphology from the perspective of alternative reproductive tactics. © 2016 The Fisheries Society of the British Isles.

  13. Age determination and validation on otoliths for two sympatric species, Mullus barbatus (Linnaeus, 1758 and Mullus surmuletus (Linnaeus, 1758, in the Adriatic Sea

    Directory of Open Access Journals (Sweden)

    Sanja Matić-Skoko

    2015-10-01

    Full Text Available In last few years, there is a strong need to establish a reliable method for age determination and validation on otoliths for Mullidae species in the Mediterranean Sea. In total, 387 specimens of Mullus surmuletus (TL 6.8 to 32.9 cm and 620 specimens of M. barbatus (TL 8.1-22.0 were analyzed. The annual periodicity of annulus deposition was supported by the otolith marginal increment analysis. The annual growth was verified using edge-type analysis. The proportion of otoliths with opaque margins was the highest (>80% in the winter period (December-March. The monthly mean marginal increment showed a single minimum in May and June for M. barbatus and M. surmuletus, respectively. Age validation was done by daily ring counting. A distance measurements analysis revealed that first regular ring appears at distance of 0.78 mm (± 0.104 SD from otolith nucleus and fish age of about 0.83 years for M. surmulets. For M. barbatus first ring appear at 0.70 mm ((± 0.100 SD at age of 0.92 years. The age analysis revealed 4 and 6 age classes for M. barbatus and M. surmuletus, respectively. Predominance of younger age classes (1+ and 2+ was observed for both species. All measured otolith morphometric parameters were linear with fish age. The most precise age estimations were obtained from the otolith width, followed by the otolith length and mass. The growth parameters were estimated by the fit of the Von Bertalanffy growth function. Although, the growth of both species was rapid up to 2 years of age and then slowed, M.barbatus exhibited faster growth. Considering the identified biological differences and their implications, existing management should be complemented by a more holistic, ecosystem approach to regulations, considered separately for each species in order to assure effective conservation measures for this economically and ecologically important fish species.

  14. Daily otolith growth and ontogenetic geochemical signatures of age-0 anchovy (Engraulis encrasicolus in the Gulf of Cádiz (SW Spain.

    Directory of Open Access Journals (Sweden)

    I. A. CATALÁN

    2014-12-01

    Full Text Available The European anchovy fishery in the Gulf of Cádiz (ICES Division IXa South is largely influenced by age-0 individuals. Knowledge of young of the year growth dynamics is crucial for management, yet data on daily growth are lacking in the area. Linking growth patterns to the environment requires information on habitat occupancy through ontogeny of the fish that reach the fishery, as anchovy use different areas of the Gulf and the Guadalquivir Estuary through development. We describe the growth dynamics of age-0 anchovy through otolith microstructure analysis, and couple these data with data on microchemical signals in the otoliths to shed light into habitat use and growth dynamics in the area. Age-0 anchovy captured in September, 2011 in the Gulf ranged from 3 to 6 months old for similar sizes, with average growth rates varying twofold. Individual non-linear growth curves showed that maximum otolith growth was positively correlated with the date of spawning, which in turn was negatively correlated with the time to reach maximum growth. There was no correlation between growth parameters and body length or condition (Fulton K at capture. The strontium:calcium (Sr/Ca and magnesium:calcium (Mg/Ca ratios were significantly lower at the edge of the otolith (approximately the age of capture than at ages corresponding to larval and early juveniles (<60 days old, but values fell within typical estuarine-dwelling species. The barium:calcium ratio (Ba/Ca increased significantly in the edge of the otolith, which possibly resulted from residency in highly productive coastal waters or from ontogenetic effects. The variance in otolith elemental ratios was larger at otolith back-calculated ages around 50 days old, age which coincides with the presumed closer dependence of estuarine waters. Our data are a first step towards understanding the contribution of the estuarine system to the fishery of anchovy in the Gulf. The limitations of the approach and future

  15. Determination of mercury in fish otoliths by cold vapor generation inductively coupled plasma mass spectrometry (CVG-ICP-MS)†

    Science.gov (United States)

    Kenduzler, Erdal; Ates, Mehmet; Arslan, Zikri; McHenry, Melanie; Tchounwou, Paul B.

    2012-01-01

    A method based on cold vapor generation inductively coupled plasma mass spectrometry (CVG-ICP-MS) has been developed for determination of inorganic mercury, Hg(II), and total mercury in fish otoliths. Sodium borohydride (NaBH4) was used as the only reducing agent and its concentration was optimized across an acidity gradient to selectively reduce Hg(II) without affecting methylmercury, CH3Hg(I). Inorganic Hg was quantitatively reduced to elemental mercury (Hg0) with 1×10−4% (m/v) NaBH4. CH3Hg(I) required a minimum of 0.5% (m/v) NaBH4 for complete reduction. Increasing the HCl concentration of solution to 5% (v/v) improved the selectivity toward Hg(II) as it decreased the signals from CH3Hg(I) to baseline levels. Potassium ferricyanide solution was the most effective in eliminating the memory effects of Hg compared with a number of chelating and oxidizing agents, including EDTA, gold chloride, thiourea, cerium ammonium nitrate and 2-mercaptoethylamine chloride. The relative standard deviation (RSD) was less than 5% for 1.0 μg L−1 Hg(II) solution. The detection limits were 4.2 and 6.4 ng L−1 (ppt) for Hg(II) and total Hg, respectively. Sample dissolution conditions and recoveries were examined with ultra-pure CaCO3 (99.99%) spiked with Hg(II) and CH3HgCl. Methylmercury was stable when dissolution was performed with up to 20% (v/v) HCl at 100 oC. Recoveries from spiked solutions were higher than 95% for both Hg(II) and CH3Hg(I). The method was applied to the determination of Hg(II) and total Hg concentrations in the otoliths of red emperor (CRM 22) and Pacific halibut. Total Hg concentration in the otoliths was 0.038 ± 0.004 μg g−1 for the red emperor and 0.021 ± 0.003 μg g−1 for the Pacific halibut. Inorganic Hg accounted for about 25% of total Hg indicating that Hg in the otoliths was predominantly organic mercury (e.g., methylmercury). However, as opposed to the bioaccumulation in tissues, methylmercury levels in otoliths was very low suggesting a

  16. Determination of mercury in fish otoliths by cold vapor generation inductively coupled plasma mass spectrometry (CVG-ICP-MS).

    Science.gov (United States)

    Kenduzler, Erdal; Ates, Mehmet; Arslan, Zikri; McHenry, Melanie; Tchounwou, Paul B

    2012-05-15

    A method based on cold vapor generation inductively coupled plasma mass spectrometry (CVG-ICP-MS) has been developed for determination of inorganic mercury, Hg(II), and total mercury in fish otoliths. Sodium borohydride (NaBH(4)) was used as the only reducing agent and its concentration was optimized across an acidity gradient to selectively reduce Hg(II) without affecting methylmercury, CH(3)Hg(I). Inorganic Hg was quantitatively reduced to elemental mercury (Hg(0)) with 1 × 10(-4)% (m/v) NaBH(4). CH(3)Hg(I) required a minimum of 0.5% (m/v) NaBH(4) for complete reduction. Increasing the HCl concentration of solution to 5% (v/v) improved the selectivity toward Hg(II) as it decreased the signals from CH(3)Hg(I) to baseline levels. Potassium ferricyanide solution was the most effective in eliminating the memory effects of Hg compared with a number of chelating and oxidizing agents, including EDTA, gold chloride, thiourea, cerium ammonium nitrate and 2-mercaptoethylamine chloride. The relative standard deviation (RSD) was less than 5% for 1.0 μg L(-1) Hg(II) solution. The detection limits were 4.2 and 6.4 ng L(-1) (ppt) for Hg(II) and total Hg, respectively. Sample dissolution conditions and recoveries were examined with ultra-pure CaCO(3) (99.99%) spiked with Hg(II) and CH(3)HgCl. Methylmercury was stable when dissolution was performed with up to 20% (v/v) HCl at 100°C. Recoveries from spiked solutions were higher than 95% for both Hg(II) and CH(3)Hg(I). The method was applied to the determination of Hg(II) and total Hg concentrations in the otoliths of red emperor (CRM 22) and Pacific halibut. Total Hg concentration in the otoliths was 0.038 ± 0.004 μg g(-1) for the red emperor and 0.021 ± 0.003 μg g(-1) for the Pacific halibut. Inorganic Hg accounted for about 25% of total Hg indicating that Hg in the otoliths was predominantly organic mercury (e.g., methylmercury). However, as opposed to the bioaccumulation in tissues, methylmercury levels in otoliths was

  17. Spatio-temporal and interspecific variation in otolith trace-elemental fingerprints in a temperate estuarine fish assemblage

    Science.gov (United States)

    Swearer, Stephen E.; Forrester, Graham E.; Steele, Mark A.; Brooks, Andrew J.; Lea, David W.

    2003-04-01

    We tested whether estuarine fishes have site-specific differences in the concentrations of trace elements in their otoliths that can be used as 'fingerprints' to identify them to their estuary of origin. To evaluate the robustness of this approach, we tested whether elemental fingerprints were consistent among individuals of five species that were collected in 1996 from three temperate estuaries in southern California. We also tested whether elemental fingerprints were consistent between spring and autumn 1996 for three species in one of the sites, Carpinteria Marsh. The species evaluated comprised a mid-water-dwelling smelt ( Atherinops affinis), two benthic gobies ( Clevelandia ios and Ilypnus gilberti), and two flatfish ( Paralichthys californicus and Hypsopsetta guttulata). The concentrations of six elements (Mn, Cu, Zn, Sr, Ba, and Pb) were determined in the otoliths using inductively coupled plasma-mass spectrometry (ICP-MS). Within estuaries, the five species exhibited strong variation in elemental concentration, indicating substantial interspecific differences in otolith environmental history. When the five fish species were considered separately, multivariate (MANOVA) and univariate (ANOVA) analyses of variance indicated that the elemental composition of otoliths differed significantly among the estuaries in four of the five species. Based on linear discriminant function analyses (DFA), differences were strong enough that trace element composition could be used to accurately assign fish to their site of origin [mean (range): 93.5% (74-100%)]. However, elemental signatures within Carpinteria Marsh were not consistent between spring and autumn 1996, and this was reflected in a substantial reduction in the accuracy of assigning fish to their true site of origin. When we compared site differences between fish species (site×species interactions), the elemental fingerprints were most similar between closely related species (e.g. the two gobies and the two

  18. Before the freeze: otoliths from the Eocene of Seymour Island, Antarctica, reveal dominance of gadiform fishes (Teleostei).

    Science.gov (United States)

    Schwarzhans, Werner; Mörs, Thomas; Engelbrecht, Andrea; Reguero, Marcelo; Kriwet, Jürgen

    2017-01-01

    The first record of fossil teleostean otoliths from Antarctica is reported. The fossils were obtained from late Early Eocene shell beds of the La Meseta Formation, Seymour Island that represent the last temperate marine climate phase in Antarctica prior to the onset of cooling and subsequent glaciation during the late Eocene. A total of 17 otolith-based teleost taxa are recognized, with 10 being identifiable to species level containing nine new species and one new genus: Argentina antarctica sp. nov., Diaphus? marambionis sp. nov., Macruronus eastmani sp. nov., Coelorinchus balushkini sp. nov., Coelorinchus nordenskjoeldi sp. nov., Palimphemus seymourensis sp. nov., Hoplobrotula? antipoda sp. nov., Notoberyx cionei gen. et sp. nov. and Cepola anderssoni sp. nov. Macruronus eastmani sp. nov. is also known from the late Eocene of Southern Australia, and Tripterophycis immutatus Schwarzhans, widespread in the southern oceans during the Eocene, has been recorded from New Zealand, southern Australia, and now Antarctica. The otolith assemblage shows a typical composition of temperate fishes dominated by gadiforms, very similar at genus and family levels to associations known from middle Eocene strata of New Zealand and the late Eocene of southern Australia, but also to the temperate Northern Hemisphere associations from the Paleocene of Denmark. The Seymour Island fauna bridges a gap in the record of global temperate marine teleost faunas during the early Eocene climate maximum. The dominant gadiforms are interpreted as the main temperate faunal component, as in the Paleocene of Denmark. Here they are represented by the families Moridae, Merlucciidae (Macruroninae), Macrouridae and Gadidae. Nowadays Gadidae are a chiefly Northern Hemisphere temperate family. Moridae, Macruroninae and Macrouridae live today on the lower shelf to deep-water or mesopelagically with Macruroninae being restricted to the Southern Ocean. The extant endemic Antarctic gadiform family

  19. Hair cell regeneration in the bullfrog vestibular otolith organs following aminoglycoside toxicity

    Science.gov (United States)

    Baird, Richard A.; Torres, M. A.; Schuff, N. R.

    1994-01-01

    Adult bullfrogs were given single intraotic injections of the aminoglycoside antibiotic gentamicin sulfate and sacrificed at postinjection times ranging from 0.5 to 9 days. The saccular and utricular maculae of normal and injected animals were examined in wholemount and cross-section. Intraotic 200 (mu) M gentamicin concentrations resulted in the uniform destruction of the hair bundles and, at later times, the cell bodies of saccular hair cells. In the utriculus, striolar hair cells were selectively damaged while extrastriolar hair cells were relatively unaffected. Regenerating hair cells, identified in sectioned material by their small cell bodies and short, well-formed hair bundles, were seen in the saccular and utricular maculae as early as 24-48 h postinjection. Immature versions of mature hair cell types in both otolith organs were recognized by the presence of absence of a bulbed kinocilia and the relative lengths of their kinocilia and longest sterocilia. Utricular hair cell types with kinocilia longer than their longest stereocilia were observed at earlier times than hair cell types with shorter kinocilia. In the same sacculus, the hair bundles of gentamicin-treated animals, even at 9 days postinjection, were significantly smaller than those of normal animals. The hair bundles of utricular hair cells, on the other hand, reached full maturity within the same time period.

  20. Anchovy (Engraulis encrasicolus otoliths reveal growth differences between two areas of the Spanish Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    Ana Ventero

    2017-09-01

    Full Text Available Anchovy is a commercial species that supports large fisheries in the Mediterranean Sea. In addition, anchovy is an essential element of the pelagic food web, playing a considerable role in connecting the lower and upper trophic levels. Comparisons made regarding length frequency distribution, demographic structure, growth during the first year inferred from otoliths, and the condition factor of anchovy inhabiting the Spanish Mediterranean Sea (General Fisheries Commission for the Mediterranean management units, GSA06-Ebro Delta and 01-Alboran Sea, based on five-year data, clearly showed significant growth differences between areas and evidenced the existence of two independent anchovy stocks in the Spanish Mediterranean Sea. The anchovies inhabiting the Alboran Sea had higher growth than the anchovies inhabiting the Ebro Delta for the same age (one year old. The dramatic decline of the Alboran Sea anchovy could be related to the current management legislation in the Spanish Mediterranean Sea, based mainly on a common minimum catch size (9 cm, which should be revised given that sustainable anchovy exploitation is crucial for the pelagic food web equilibrium.

  1. Effects of functional groups and soluble matrices in fish otolith on calcium carbonate mineralization.

    Science.gov (United States)

    Ren, Dongni; Li, Zhuo; Gao, Yonghua; Feng, Qingling

    2010-10-01

    Calcium carbonate mineralization is significantly influenced by organic matrices in vivo. The effect mainly relies on functional groups in proteins. In order to study the influence of functional groups on calcium carbonate mineralization, -OH, -NH2 and -COOH groups were grafted onto single crystal silicon chips, and such modified chips were used as substrates in in vitro mineralization experiments. An x-ray photoelectron spectroscopy (XPS) test was conducted to examine the grafting efficiency, and the three groups were successfully grafted. Calcium carbonate mineralization on a modified silicon substrate was examined by a scanning electron microscope (SEM) and x-ray diffraction (XRD), and the results showed that the effects of -OH, -NH2 and -COOH groups were quite different. Furthermore, a water-soluble protein matrix (WSM) and an acid-soluble protein matrix (ASM) extracted from fish otolith were adsorbed onto the -COOH-modified silicon substrate, and the effects of the protein matrices on calcium carbonate mineralization were studied. The results showed that both WSM and ASM of lapillus could mediate aragonite crystallization, but the size and morphology of the formed crystals were different. The WSM and ASM of asteriscus adsorbed on the silicon substrate had little effect on calcium carbonate mineralization; almost all the crystals were calcite, while both asteriscus WSM and ASM in solution could mediate vaterite crystals, and the morphologies of vaterite crystal aggregates were different.

  2. Species and life-history affects the utility of otolith chemical composition to determine natal stream-of-origin in Pacific salmon

    Science.gov (United States)

    Zimmerman, Christian E.; Swanson, Heidi K.; Volk, Eric C.; Kent, Adam J.R.

    2013-01-01

    To test the utility of otolith chemical composition as a tool for determining the natal stream of origin for salmon, we examined water chemistry and otoliths of juvenile and adult Chum Salmon Oncorhynchus keta and Coho Salmon O. kisutch from three watersheds (five rivers) in the Norton Sound region of Alaska. The two species are characterized by different life histories: Coho Salmon rear in freshwater for up to 3 years, whereas Chum Salmon emigrate from freshwater shortly after emergence. We used laser ablation (LA) inductively coupled plasma (ICP) mass spectrometry (MS) to quantify element: Ca ratios for Mg, Mn, Zn, Sr, and Ba, and we used multicollector LA-ICP-MS to determine 87Sr:86Sr ratios in otolith regions corresponding to the period of freshwater residence. Significant differences existed in both water and otolith elemental composition, suggesting that otolith composition could be used to discriminate the natal origin of Coho Salmon and Chum Salmon but only when 87Sr:86Sr ratios were included in the discriminant function analyses. The best discriminant model included 87Sr:86Sr ratios, and without 87Sr:86Sr ratios it was difficult to discriminate among watersheds and rivers. Classification accuracy was 80% for Coho Salmon and 68% for Chum Salmon, indicating that this method does not provide sufficient sensitivity to estimate straying rates of Pacific salmon at the scale we studied.

  3. Otolith morphology and body size relationships for juvenile Sciaenidae in the Río de la Plata estuary (35-36°S

    Directory of Open Access Journals (Sweden)

    Juan A. Waessle

    2003-06-01

    Full Text Available Seven species of the family Sciaenidae have been reported inhabiting bottom waters of the Río de la Plata estuary. Of these juvenile stripped weakfish (Cynoscion guatucupa, king weakfish (Macrodon ancylodon, whitemouth croaker (Micropogonias furnieri and banded ground drum (Paralonchurus brasiliensis are by far the most abundant. These species are also important prey of several top-predator species among large fishes, seabirds and mammals. In this study we provide new information regarding otolith morphology and body size relationships of juvenile sciaenid fish. The sagittae morphology of juvenile sciaenids showed strong changes in the course of their development (e.g. in overall shape and development of concrescences on the outer surface. Analysing the morphometric relationships, we concluded that otolith length and otolith mass are good indicators of fish standard length and fish weight in all species. If otolith length or mass is used to estimate fish length, the regression explained more than 97% of the variation in all species. All equations relating fish standard length and fish weight for juvenile stages of the species studied explained a very large proportion of the variance in the data. These data will help researchers studying food habits of top predators to determine size and weight of usually juvenile fish-prey from length, broad and/or weight of recovered otoliths.

  4. Atlas of marine bony fish otoliths (Sagittae of Southeastern - Southern Brazil Part I: Gadiformes (Macrouridae, Moridae, Bregmacerotidae, Phycidae and Merlucciidae; Part II: Perciformes (Carangidae, Sciaenidae, Scombridae and Serranidae

    Directory of Open Access Journals (Sweden)

    Carmen Lucia Del Bianco Rossi-Wongtschowski

    2014-01-01

    Full Text Available The drawings, detailed pictures, precise descriptions and measurements that characterize otoliths must be made available for studies in various areas, including taxonomy, phylogeny, ecology, fisheries, paleontology, diversity, predator-prey relationships and modeling. The Collection of Teleostei Fish Otoliths of Southeastern-Southern Brazil (COSS-Brasil of IOUSP contains 45,000 pairs of otoliths from 210 species. This publication is the first in a series that will constitute an atlas of Teleostei otoliths for southeastern-southern Brazil and presents the results of the morphologic and morphometric analyses of 11 Gadiformes and 36 Perciformes species by means of the most commonly used features, measurements and indices. Three otoliths of each species were illustrated and photographed whenever possible. The frequency of occurrence was calculated for each characteristic by total length classes (TL, and the ontogenetic differences were analyzed (multiple χ2 test; significance 0.05. Morphometric analyses were conducted for each characteristic per total length (TL class and for the whole sample, and the ontogenetic differences were analyzed.

  5. An otolith microchemistry study of possible relationships between the origins of leptocephali of European eels in the Sargasso Sea and the continental destinations and relative migration success of glass eels

    DEFF Research Database (Denmark)

    Martin, J.; Daverat, F.; Pécheyran, C.

    2010-01-01

    Little is known about the extent to which Atlantic eels coming from different European rivers converge on the same spawning site. Our aim was to evaluate the spatial homogeneity of eel spawning area(s) with an otolith microchemistry approach. This work compared the elemental signatures of otolith...

  6. Using trace elements in otoliths to discriminate between wild and farmed European sea bass (Dicentrarchus labrax L. and Gilthead sea bream (Sparus aurata L.

    Directory of Open Access Journals (Sweden)

    P. Arechavala-Lopez

    2016-08-01

    Full Text Available Abstract Trace elements in otoliths of sea bass (Dicentrarchus labrax L. and sea bream (Sparus aurata L. from fish farms and coastal wild populations in the western Mediterranean Sea were analysed by inductively coupled plasma-mass spectrometry. Results showed that concentrations of Mg, K, and Mn differed significantly between wild and farmed sea bass, while concentrations of Mg, K, Mn, Fe, Zn, Sr, and Ba varied significantly between wild and farmed sea bream. Discriminate analysis and cross-validation classification showed that the trace element profile in otoliths can be used to separate farmed fish from wild stocks with high accuracy on both sea bass (individuals correctly classified: 90.7 % and sea bream (individuals correctly classified: 96.6 %. Moreover, trace elements in otoliths resulted to be useful to discriminate among wild fish stocks within each species.

  7. Age, growth rate, and otolith growth of polar cod (Boreogadus saida in two fjords of Svalbard, Kongsfjorden and Rijpfjorden

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    Dariusz P. Fey

    2017-10-01

    Full Text Available This work presents biological information for polar cod (Boreogadus saida collected with a Campelen 1800 shrimp bottom trawl in Kongsfjorden (two stations located in the inner part of the fjord adjacent to the glacier and Rijpfjorden (one station at the entrance to the fjord in September and October 2013. The otolith-based ages of polar cod collected in Kongsfjorden (6.1–24 cm total length TL; n = 813 ranged from 0 to 4 years. The growth rate was relatively constant at approximately 4.7 cm year−1 between years 1 and 4, which indicates that growth was fast in the glacier area. The ages of polar cod collected in Rijpfjorden (8.6–15.9 cm TL; n = 64 ranged from 2 to 3 years. The fish from Rijpfjorden were smaller at age than those from Kongsfjorden, and their growth rate between years 2 and 3 (no other age classes were available was approximately 3.3 cm year−1. In both fjords, males and females were of the same size-at-age and the same weight-at-TL. The small sampling area means that the results on growth rate are not representative of the entire fjords. Instead, the results can be discussed as presenting the possible growth rates of some populations. A strong relationship was identified between otolith size (length and weight and fish size (TL and TW, with no differences between males and females or the fjords. A significant, strong relationship was also noted between fish and otolith growth rates.

  8. The Mangrove Nursery Paradigm Revisited: Otolith Stable Isotopes Support Nursery-to-Reef Movements by Indo-Pacific Fishes

    Science.gov (United States)

    Kimirei, Ismael A.; Nagelkerken, Ivan; Mgaya, Yunus D.; Huijbers, Chantal M.

    2013-01-01

    Mangroves and seagrass beds have long been perceived as important nurseries for many fish species. While there is growing evidence from the Western Atlantic that mangrove habitats are intricately connected to coral reefs through ontogenetic fish migrations, there is an ongoing debate of the value of these coastal ecosystems in the Indo-Pacific. The present study used natural tags, viz. otolith stable carbon and oxygen isotopes, to investigate for the first time the degree to which multiple tropical juvenile habitats subsidize coral reef fish populations in the Indo Pacific (Tanzania). Otoliths of three reef fish species (Lethrinus harak, L. lentjan and Lutjanus fulviflamma) were collected in mangrove, seagrass and coral reef habitats and analyzed for stable isotope ratios in the juvenile and adult otolith zones. δ13C signatures were significantly depleted in the juvenile compared to the adult zones, indicative of different habitat use through ontogeny. Maximum likelihood analysis identified that 82% of adult reef L. harak had resided in either mangrove (29%) or seagrass (53%) or reef (18%) habitats as juveniles. Of adult L. fulviflamma caught from offshore reefs, 99% had passed through mangroves habitats as juveniles. In contrast, L. lentjan adults originated predominantly from coral reefs (65–72%) as opposed to inshore vegetated habitats (28–35%). This study presents conclusive evidence for a nursery role of Indo-Pacific mangrove habitats for reef fish populations. It shows that intertidal habitats that are only temporarily available can form an important juvenile habitat for some species, and that reef fish populations are often replenished by multiple coastal habitats. Maintaining connectivity between inshore vegetated habitats and coral reefs, and conserving habitat mosaics rather than single nursery habitats, is a major priority for the sustainability of various Indo Pacific fish populations. PMID:23776658

  9. Radiocarbon in otoliths of yelloweye rockfish (Sebastes ruberrimus): a reference time series for the coastal waters of southeast Alaska

    Energy Technology Data Exchange (ETDEWEB)

    Kerr-Ferrey, L A; Andrews, A H; Frantz, B R; Coale, K H; Brown, T A; Cailliet, G M

    2003-10-14

    Atmospheric testing of thermonuclear devices during the 1950s and 1960s created a global radiocarbon ({sup 14}C) signal in the environment that has provided a useful tracer and chronological marker in oceanic systems and organisms. The bomb-generated {sup 14}C signal retained in fish otoliths can be used as a permanent, time-specific recorder of the 14C present in ambient seawater, making it a useful tool in age validation of fishes. The goal of this study was to determine {sup 14}C levels in otoliths of the age-validated yelloweye rockfish (Sebastes ruberrimus) to establish a reference time series for the coastal waters of southeast Alaska. Radiocarbon values from the first year's growth of 43 yelloweye rockfish otoliths were plotted against estimated birth year to produce a 14C time series for these waters spanning 1940 to 1990. The time series shows the initial rise of bomb 14C occurred in 1958 in coastal southeast Alaskan waters and {sup 14}C levels rose relatively rapidly to peak {Delta}{sup 14}C values (60-70%) between 1966 and 1971, with a subsequent declining trend through the end of the record in 1990 (-3.2%). In addition, the radiocarbon data, independent of the radiometric study, confirms the longevity of the yelloweye rockfish up to a minimum of 44 years and strongly supports higher age estimates. The yelloweye rockfish record provides a {sup 14}C chronology that will be useful for the interpretation of {sup 14}C accreted in biological samples from these waters and in future rockfish age validation studies.

  10. Water temperature and fish growth: otoliths predict growth patterns of a marine fish in a changing climate.

    Science.gov (United States)

    Rountrey, Adam N; Coulson, Peter G; Meeuwig, Jessica J; Meekan, Mark

    2014-08-01

    Ecological modeling shows that even small, gradual changes in body size in a fish population can have large effects on natural mortality, biomass, and catch. However, efforts to model the impact of climate change on fish growth have been hampered by a lack of long-term (multidecadal) data needed to understand the effects of temperature on growth rates in natural environments. We used a combination of dendrochronology techniques and additive mixed-effects modeling to examine the sensitivity of growth in a long-lived (up to 70 years), endemic marine fish, the western blue groper (Achoerodus gouldii), to changes in water temperature. A multi-decadal biochronology (1952-2003) of growth was constructed from the otoliths of 56 fish collected off the southwestern coast of Western Australia, and we tested for correlations between the mean index chronology and a range of potential environmental drivers. The chronology was significantly correlated with sea surface temperature in the region, but common variance among individuals was low. This suggests that this species has been relatively insensitive to past variations in climate. Growth increment and age data were also used in an additive mixed model to predict otolith growth and body size later this century. Although growth was relatively insensitive to changes in temperature, the model results suggested that a fish aged 20 in 2099 would have an otolith about 10% larger and a body size about 5% larger than a fish aged 20 in 1977. Our study shows that species or populations regarded as relatively insensitive to climate change could still undergo significant changes in growth rate and body size that are likely to have important effects on the productivity and yield of fisheries. © 2014 John Wiley & Sons Ltd.

  11. Preliminary indication of ontogenetic and spatial variations in the whole otolith isotopic and elemental signatures of Solea solea in the Gulf of Lions (NW Mediterranean

    Directory of Open Access Journals (Sweden)

    Fabien Morat

    2012-11-01

    Full Text Available Knowledge of fish life cycles is important for exploited species. In the Mediterranean Sea, catches of common sole (Solea solea have fluctuated widely since the 1970s. Solea solea displays an ontogenetic shift in habitat: sole larvae are marine, juveniles inhabit shallow marine waters and coastal lagoons and adults inhabit deeper marine waters. Although the results of this study were obtained using only a small set of individuals, the otolith elemental composition and isotopic ratios were investigated for the three life stages (post-larval, juvenile and adult in order to acquire a better knowledge of the variability in environmental conditions experienced by the common sole at each life stage in the NW Mediterranean. Moreover, this study provides the first evaluation of the potential of whole otolith microchemistry for investigating habitat connectivity in sole populations from the Gulf of Lions. The elemental and isotopic signatures of otoliths of post-larvae captured in various environments appear to show variations related to the River Rhône inputs (high Ba/Ca and low Sr/Ca ratios. Juveniles appear to show significant variations in otolith elemental and isotopic compositions depending not only on the physico-chemical properties of water in the nurseries they inhabit (Rhône River, Thau or Mauguio lagoons, but also as a result of variations in the chemical composition of their surrounding sediments and in their benthic prey. Adults exhibit otolith differences for isotopic ratios only, which is probably linked to the River Rhône inputs. Finally, several significant relationships were observed between otolith elemental composition and fish size in specimens captured at the River Rhône mouth. However, these variations seem to be an indication of the composition acquired in each environment rather than a sign of ontogeny.

  12. Interactive effect of hypoxia and otolith organ engagement on cardiovascular regulation in humans

    Science.gov (United States)

    Monahan, Kevin D.; Ray, Chester A.

    2002-01-01

    We determined the interaction between the vestibulosympathetic reflex and the arterial chemoreflex in 12 healthy subjects. Subjects performed three trials in which continuous recordings of muscle sympathetic nerve activity (MSNA), mean arterial blood pressure (MAP), heart rate (HR), and arterial oxygen saturation were obtained. First, in prone subjects the otolith organs were engaged by use of head-down rotation (HDR). Second, the arterial chemoreflex was activated by inspiration of hypoxic gas (10% O2 and 90% N2) for 7 min with HDR being performed during minute 6. Third, hypoxia was repeated (15 min) with HDR being performed during minute 14. HDR [means +/- SE; increase (Delta)7 +/- 1 bursts/min and Delta50 +/- 11% for burst frequency and total MSNA, respectively; P < 0.05] and hypoxia (Delta6 +/- 2 bursts/min and Delta62 +/- 29%; P < 0.05) increased MSNA. Additionally, MSNA increased when HDR was performed during hypoxia (Delta11 +/- 2 bursts/min and Delta127 +/- 57% change from normoxia; P < 0.05). These increases in MSNA were similar to the algebraic sum of the individual increase in MSNA elicited by HDR and hypoxia (Delta13 +/- 1 bursts/min and Delta115 +/- 36%). Increases in MAP (Delta3 +/- 1 mmHg) and HR (Delta19 +/- 1 beats/min) during combined HDR and hypoxia generally were smaller (P < 0.05) than the algebraic sum of the individual responses (Delta5 +/- 1 mmHg and Delta24 +/- 2 beats/min for MAP and HR, respectively; P < 0.05). These findings indicate an additive interaction between the vestibulosympathetic reflex and arterial chemoreflex for MSNA. Therefore, it appears that MSNA outputs between the vestibulosympathetic reflex and arterial chemoreflex are independent of one another in humans.

  13. Determination of mercury in fish otoliths by cold vapor generation inductively coupled plasma mass spectrometry (CVG-ICP-MS)†

    OpenAIRE

    Kenduzler, Erdal; Ates, Mehmet; Arslan, Zikri; McHenry, Melanie; Tchounwou, Paul B.

    2012-01-01

    A method based on cold vapor generation inductively coupled plasma mass spectrometry (CVG-ICP-MS) has been developed for determination of inorganic mercury, Hg(II), and total mercury in fish otoliths. Sodium borohydride (NaBH4) was used as the only reducing agent and its concentration was optimized across an acidity gradient to selectively reduce Hg(II) without affecting methylmercury, CH3Hg(I). Inorganic Hg was quantitatively reduced to elemental mercury (Hg0) with 1×10−4% (m/v) NaBH4. CH3Hg...

  14. Life history traits of the fish community in Lake Annecy: evidence from the stable isotope composition of otoliths

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    Gerdeaux D.

    2015-01-01

    Full Text Available Stable isotope analysis (SIA of fish otoliths shows great potential for exploring the ecology of fish, but this method has not been applied to the study of lacustrine fish communities. Both sequential and whole-otolith SIAs were performed on six fish species of Lake Annecy and their results compared to muscle SIA. The first purpose of these investigations was to test the use of δ18Ooto values for reconstructing fish thermal history and delimiting spatial distribution in a stratified lake. Comparison of species-specific fractionation equations and the general equation developed for freshwater fishes showed that the general one was the best suited for thermal estimation of Lake Annecy fishes and suggested that inter-specific differences or specific “vital effects” are not the only reason for apparent difference in fractionation. Thermal estimations based on SIA were consistent with descriptions of thermal habitats in the literature, except in the case of roach (Rutilus rutilus. Based on the current results, roach appears to live in a colder habitat than do perch (Perca fluviatilis. The high water transparency and thermal stratification of Lake Annecy could explain this distribution. Moreover, perch juveniles were found to live in two different thermal niches. This finding highlights the great plasticity of the species. Second, the potential use of δ13Coto values to reconstruct variation in diet and metabolism was assessed. The proportion of metabolic carbon (M contributing to otolith carbon varies markedly among species. Comparison with δ13Cmuscle values shows no direct relationship between δ13Coto and diet at either the intra-individual or the inter-specific level. A strong linear relationship between either M or the isotopic offset between otolith and muscle (Δδ13Coto - muscle and δ18Ooto values was found; this relationship reveals the dependence of M on the ambient temperature at which the species occurs. This relationship might be

  15. The Otolith Group’s “Monuments to Dead Television.” Independent Cinema and the Migrant Experience in Europe between Television and the Museum

    Directory of Open Access Journals (Sweden)

    Beatrice Ferrara

    2014-04-01

    Full Text Available “Monument to dead television” is the expression the British collective The Otolith Group uses to define its activity of recuperating long-lost quality films, and re-screening them in contemporary art museums and gallery spaces. What these films share is a cinematic vocation and a complex approach to the question of memory and migration in Europe, and to the role of images as testimonies or documents. This essay explores The Otolith Group’s interest in such forgotten archives of modern television in order to unearth their significance for contemporary museums today.

  16. Destructive and non-destructive microanalysis of biocarbonates applied to anomalous otoliths of archaeological and modern sciaenids (Teleostei) from Peru and Chile.

    Science.gov (United States)

    Béarez, Philippe; Carlier, Gabriel; Lorand, Jean-Pierre; Parodi, Gian-Carlo

    2005-03-01

    Anomalous otoliths were discovered among modern and archaeological (8th millennium BP) sciaenids. The two species concerned, Cilus gilberti and Sciaena deliciosa, are common on the Peruvian-Chilean coast and do not seem to be affected by this morphological anomaly that maintained in their populations for thousands of years. The carbonates of the anomalous forms, determined by X-ray diffraction, are different from that of the normal otoliths, i.e. calcite and vaterite instead of aragonite. A method of non-destructive analysis by cathodoluminescence is tested and assumptions on the origin of the anomaly and its possible implications on environmental studies are advanced.

  17. Evidence of estuarine nursery origin of five coastal fish species along the Portuguese coast through otolith elemental fingerprints

    Science.gov (United States)

    Vasconcelos, Rita P.; Reis-Santos, Patrick; Tanner, Susanne; Maia, Anabela; Latkoczy, Christopher; Günther, Detlef; Costa, Maria José; Cabral, Henrique

    2008-08-01

    Connectivity is a critical property of marine populations, particularly for species with segregated juvenile and adult habitats. Knowledge of this link is fundamental in understanding population structure and dynamics. Young adults of commercially important fish species Solea solea, Solea senegalensis, Platichthys flesus, Diplodus vulgaris and Dicentrarchus labrax were sampled off the Portuguese coast in order to establish preliminary evidence of estuarine nursery origins through otolith elemental fingerprints. Concentrations of Li, Na, Mg, K, Mn, Cu, Zn, Sr, Ba and Pb in the otolith section corresponding to juvenile's nursery life period were determined through laser ablation inductively coupled plasma mass spectrometry. Element: Ca ratios in coastal fish differed significantly amongst collection areas, except for Platichthys flesus, and were compared with the elemental fingerprints previously defined for age 0 juveniles in the main estuarine nurseries of the Portuguese coast. Identification of nursery estuaries was achieved for four of the species. Assigned nursery origins varied amongst species and differences in the spatial scale of fish dispersal were also found. Diplodus vulgaris was not reliably assigned to any of the defined nurseries. Overall, results give evidence of the applicability of estuarine habitat tags in future assessments of estuarine nursery role. Research developments on the links between juvenile and adult habitats should contribute for the integrated management and conservation of nurseries and coastal stocks.

  18. Vestibulo-Ocular Responses to Vertical Translation using a Hand-Operated Chair as a Field Measure of Otolith Function

    Science.gov (United States)

    Wood, S. J.; Campbell, D. J.; Reschke, M. F.; Prather, L.; Clement, G.

    2016-01-01

    The translational Vestibulo-Ocular Reflex (tVOR) is an important otolith-mediated response to stabilize gaze during natural locomotion. One goal of this study was to develop a measure of the tVOR using a simple hand-operated chair that provided passive vertical motion. Binocular eye movements were recorded with a tight-fitting video mask in ten healthy subjects. Vertical motion was provided by a modified spring-powered chair (swopper.com) at approximately 2 Hz (+/- 2 cm displacement) to approximate the head motion during walking. Linear acceleration was measured with wireless inertial sensors (Xsens) mounted on the head and torso. Eye movements were recorded while subjects viewed near (0.5m) and far (approximately 4m) targets, and then imagined these targets in darkness. Subjects also provided perceptual estimates of target distances. Consistent with the kinematic properties shown in previous studies, the tVOR gain was greater with near targets, and greater with vision than in darkness. We conclude that this portable chair system can provide a field measure of otolith-ocular function at frequencies sufficient to elicit a robust tVOR.

  19. Combining microsatellite, otolith shape and parasites community analyses as a holistic approach to assess population structure of Dentex dentex

    Science.gov (United States)

    Marengo, M.; Baudouin, M.; Viret, A.; Laporte, M.; Berrebi, P.; Vignon, M.; Marchand, B.; Durieux, E. D. H.

    2017-10-01

    The common dentex, Dentex dentex, is an iconic marine coastal fish of the Mediterranean Sea. Despite its economic and ecological importance, data on the population structure of this species are still very limited. The aim of this study was to identify the stock structure of the common dentex at relatively fine spatial scale around Corsica Island, using a combination of markers that have different spatial and temporal scales of integration: microsatellite DNA markers, otolith shape analysis and parasites communities. Microsatellite analysis indicated that there was no significant genetic differentiation in D. dentex between the four sampling sites around Corsica. Otolith shape analysis suggests one potential distinct population unit of D. dentex centered in one site (Cap Corse) varying in their degree of differentiation from those in the other zones. Multivariate analysis on parasite abundance data highlights to a lower extent two sites (Bonifacio and Galeria) with some connectivity between adjacent zones. The combination of these three markers together highlights the resulting three sites while giving complementary insights and an opportunity to compare their utility and potential to understand population interactions. A complex population structure around Corsican coasts is then proposed, providing a new perspective on common dentex fishery stock conservation and management strategies.

  20. Evaluation of removal of the size effect using data scaling and elliptic Fourier descriptors in otolith shape analysis, exemplified by the discrimination of two yellow croaker stocks along the Chinese coast

    Science.gov (United States)

    Zhao, Bo; Liu, Jinhu; Song, Junjie; Cao, Liang; Dou, Shuozeng

    2017-11-01

    Removal of the length effect in otolith shape analysis for stock identification using length scaling is an important issue; however, few studies have attempted to investigate the effectiveness or weakness of this methodology in application. The aim of this study was to evaluate whether commonly used size scaling methods and normalized elliptic Fourier descriptors (NEFDs) could effectively remove the size effect of fish in stock discrimination. To achieve this goal, length groups from two known geographical stocks of yellow croaker, Larimichthys polyactis, along the Chinese coast (five groups from the Changjiang River estuary of the East China Sea and three groups from the Bohai Sea) were subjected to otolith shape analysis. The results indicated that the variation of otolith shape caused by intra-stock fish length might exceed that due to inter-stock geographical separation, even when otolith shape variables are standardized with length scaling methods. This variation could easily result in misleading stock discrimination through otolith shape analysis. Therefore, conclusions about fish stock structure should be carefully drawn from otolith shape analysis because the observed discrimination may primarily be due to length effects, rather than differences among stocks. The application of multiple methods, such as otoliths shape analysis combined with elemental fingering, tagging or genetic analysis, is recommended for sock identification.

  1. Otolith shape analysis as a tool for stock discrimination of the black scabbardfish, Aphanopus carbo Lowe, 1839 (Pisces: Trichiuridae, in Portuguese waters

    Directory of Open Access Journals (Sweden)

    Inês Farias

    2009-12-01

    Full Text Available The variability in otolith contour shape of black scabbardfish (Aphanopus carbo from Portuguese waters was analysed for stock discrimination purposes. The contour shape of otoliths from specimens caught off mainland Portugal, Madeira and Azores archipelagos was digitised and extracted according to the closed-form Fourier analysis technique. Mainland and Madeira specimens were compared through the adjustment of a MANOVA model to the normalised elliptic Fourier descriptor (NEFDs obtained for the otoliths of 200 females and 200 males sampled at each area. Significant differences were found between areas and between sexes; the interaction term was not statistically significant. The effect of the area also proved to be significant when samples from the three regions were considered. These results were further supported by the discriminant analysis of the individual NEFDs for which the correct classifications were 87.5-89% when they were considered by sex and total length for the mainland and Madeira, and 90.9-97.7%, when NEFDs from the three areas were compared by sex and fish length. Otolith contour shape was shown to be a possible tool for differentiating between black scabbardfish stocks in the NE Atlantic.

  2. Potential effects of hydroelectric dam development in the Mekong River basin on the migration of Siamese mud carp (Henicorhynchus siamensis and H. lobatus elucidated by otolith microchemistry.

    Directory of Open Access Journals (Sweden)

    Michio Fukushima

    Full Text Available The migration of Siamese mud carp (Henicorhynchus siamensis and H. lobatus, two of the most economically important fish species in the Mekong River, was studied using an otolith microchemistry technique. Fish and river water samples were collected in seven regions throughout the whole basin in Thailand, Laos and Cambodia over a 4 year study period. There was coherence between the elements in the ambient water and on the surface of the otoliths, with strontium (Sr and barium (Ba showing the strongest correlation. The partition coefficients were 0.409-0.496 for Sr and 0.055 for Ba. Otolith Sr-Ba profiles indicated extensive synchronized migrations with similar natal origins among individuals within the same region. H. siamensis movement has been severely suppressed in a tributary system where a series of irrigation dams has blocked their migration. H. lobatus collected both below and above the Khone Falls in the mainstream Mekong exhibited statistically different otolith surface elemental signatures but similar core elemental signatures. This result suggests a population originating from a single natal origin but bypassing the waterfalls through a passable side channel where a major hydroelectric dam is planned. The potential effects of damming in the Mekong River are discussed.

  3. Use of otolith strontium:calcium and zinc:calcium ratios as an indicator of the habitat of Percophis brasiliensis Quoy & Gaimard, 1825 in the southwestern Atlantic Ocean

    Directory of Open Access Journals (Sweden)

    Esteban Avigliano

    Full Text Available We evaluate the simultaneous use of Sr: Ca and Zn: Ca ratios of the sagitta otolith as a potential indicator of the habitat of Percophis brasiliensis along a latitudinal gradient in the southwestern Atlantic Ocean (34-42ºS and 51-67ºW, in order to reliably identify fish stocks. Fish were collected in three sampling sites: Argentine-Uruguayan Common Fishing Zone (AUCFZ, El Rincón (ER and San Matías Gulf (SMG. The otolith Sr:Ca and Zn:Ca ratios were determined by ICP-OES and EDTA volumetric method. The otolith Sr:Ca ratio was similar in the three sampling sites, while the Zn:Ca ratio was significantly higher in AUCFZ than in ER and SMG for all age groups. The discriminant analysis showed an association between the otolith Sr:Ca and Zn:Ca ratios from ER and SMG. Present results suggest the potential occurrence of two fish stocks of P. brasiliensis in the study area.

  4. Beyond the transect: An alternative microchemical imaging method for fine scale analysis of trace elements in fish otoliths during early life

    Energy Technology Data Exchange (ETDEWEB)

    McGowan, Nicole [Elemental Bio-imaging Facility, University of Technology, Sydney, New South Wales (Australia); CCFS ARC Centre of Excellence, Department of Earth and Planetary Sciences, Macquarie University, Sydney (Australia); Fowler, Ashley M.; Parkinson, Kerryn [Fish Ecology Laboratory, School of the Environment, University of Technology, Sydney, New South Wales (Australia); Bishop, David P. [Elemental Bio-imaging Facility, University of Technology, Sydney, New South Wales (Australia); Ganio, Katherine [Florey Department of Neuroscience and Mental Health, University of Melbourne, Victoria (Australia); Doble, Philip A. [Elemental Bio-imaging Facility, University of Technology, Sydney, New South Wales (Australia); Booth, David J. [Fish Ecology Laboratory, School of the Environment, University of Technology, Sydney, New South Wales (Australia); Hare, Dominic J., E-mail: dominic.hare@uts.edu.au [Elemental Bio-imaging Facility, University of Technology, Sydney, New South Wales (Australia); Florey Department of Neuroscience and Mental Health, University of Melbourne, Victoria (Australia)

    2014-10-01

    Microchemical analysis of otolith (calcified ‘ear stones’ used for balance and orientation) of fishes is an important tool for studying their environmental history and management. However, the spatial resolution achieved is often too coarse to examine short-term events occurring in early life. Current methods rely on single points or transects across the otolith surface, which may provide a limited view of elemental distributions, a matter that has not previously been investigated. Imaging by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) permits microchemical analyses of short-term events in early life with high (< 10 μm) resolution, two-dimensional (2D) visualization of elemental distributions. To demonstrate the potential of this method, we mapped the concentrations of Sr and Ba, two key trace elements, in a small number of juvenile otoliths of neon damselfish (Pomacentrus coelestis) using an 8 μm beam diameter (laser fluence of 13.8 ± 3.5 J cm{sup −2}). Quantification was performed using the established method by Longerich et al. (1996), which is applied to 2D imaging of a biological matrix here for the first time. Accuracy of > 97% was achieved using a multi-point non matrix-matched calibration of National Institute of Standards and Technology (NIST) 610 and 612 (trace elements in glass) using Longerich's calculation method against the matrix-matched standard FEBS-1 (powdered red snapper [Lutjanus campechanus] otolith). The spatial resolution achieved in the otolith corresponded to a time period of 2 ± 1 days during the larval phase, and 4 ± 1 days during the post-settlement juvenile phase. This method has the potential to improve interpretations of early life-history events at scales corresponding to specific events. While the images showed gradients in Sr and Ba across the larval settlement zone more clearly than single transects, the method proved sample homogeneity throughout the structure; demonstrating that 2D

  5. Atlas of marine bony fish otoliths (sagittae of Southeastern-Southern Brazil Part V: Perciformes (Sparidae, Sciaenidae, Polynemidae, Mullidae, Kyphosidae, Chaetodontidae, Mugilidae, Scaridae, Percophidae, Pinguipedidae, Blenniidae, Gobiidae, Ephippidae, Sphyraenidae, Gempylidae, Trichiuridae, Scombridae, Ariommatidae, Stromateidae and Caproidae

    Directory of Open Access Journals (Sweden)

    Cesar Santificetur

    Full Text Available ABSTRACT This publication is part of a series prepared with the purpose to constitute an Atlas of Teleostei Otoliths for the Southeastern-Southern Brazilian area. Here we present the results of 15 morphological features and six shape indices for 33 Perciformes species of 20 families. Whenever available in out collection, three otoliths of each species were illustrated and photographed. The frequency of occurrence of each feature was calculated inside and among total length classes being the differences analyzed through multiple χ2 tests (significance level 0.05. Based on otoliths measurements, six shape indices values were obtained being the minimum, maximum, mean and standard deviations values presented.

  6. Trace element-protein interactions in endolymph from the inner ear of fish: implications for environmental reconstructions using fish otolith chemistry.

    Science.gov (United States)

    Thomas, Oliver R B; Ganio, Katherine; Roberts, Blaine R; Swearer, Stephen E

    2017-03-22

    Otoliths, the biomineralised hearing "ear stones" from the inner ear of fish, grow throughout the lifespan of an individual, with deposition of alternating calciferous and proteinaceous bands occurring daily. Trace element : calcium ratios within daily increments measured by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) are often used in fisheries science to reconstruct environmental histories. There is, however, considerable uncertainty as to which elements are interacting with either the proteinaceous or calciferous zones of the otolith, and thus their utility as indicators of environmental change. To answer this, we used size exclusion chromatography-inductively coupled plasma-mass spectrometry (SEC-ICP-MS) of endolymph, the otolith growth medium, to determine the binding interactions for a range of elements. In addition, we used solution ICP-MS to quantify element concentrations in paired otolith and endolymph samples and determined relative enrichment factors for each. We found 12 elements that are present only in the proteinaceous fraction, 6 that are present only in the salt fraction, and 4 that are present in both. These findings have important implications for the reconstruction of environmental histories based on changes in otolith elemental composition: (1) elements occurring only in the salt fraction are most likely to reflect changes in the physico-chemical environment experienced during life; (2) elements occurring only in the proteinaceous fraction are more likely to reflect physiological rather than environmental events; and (3) elements occurring in both the salt and proteinaceous fractions are likely to be informative about both endogenous and exogenous processes, potentially reducing their utility in environmental reconstructions.

  7. Environmental migratory patterns and stock identification of Mugil cephalus in the Spanish Mediterranean Sea, by means of otolith microchemistry

    Science.gov (United States)

    Callicó Fortunato, Roberta; Reguera Galán, Aida; García Alonso, Ignacio; Volpedo, Alejandra; Benedito Durà, Vicent

    2017-03-01

    The Flathead grey mullet, Mugil cephalus is the most globally-distributed Mugilidae species and its migrations and movement patterns have been studied globally but not in-depth in the Mediterranean region. Thus, the present study aimed: (1) to identify migratory patterns throughout the life-history of the Mugil cephalus in different Spanish Mediterranean wetlands, and (2) to study the presence of potential fish stocks of the species in the region, by means of otolith microchemistry. Specimens (n = 43) were obtained in three wetlands: Parque Natural Delta del Ebro (DE), a stratified estuary; Parque Natural de l'Albufera de Valencia (AV), a Mediterranean lake; and Parque Natural Salinas de Santa Pola (SP), a coastal salt marsh. Otolith microchemistry was studied using LA-ICP-MS (chronological variation of Sr:Ca and Ba:Ca ratios). The analysis of lifetime profiles revealed four behavioral patterns: Type I: most frequent use of estuarine environments (estuarine resident); Type II: freshwater behaviour during early life history, moving though estuarine to marine waters at the end of their profile (freshwater migrant); Type III: estuarine water use in early life stages moving then towards sea waters (estuarine migrant); and Type IV: sea/high salinity water habitat use during their entire lifetime (seawater resident). A Canonical Discriminant Analysis, using Sr:Ca and Ba:Ca ratios from core and edge as variables, assigned individuals to the detected patterns with high accuracy (Type I > 95%; Type II and Type III > 83%; and Type IV > 88%). Moreover, two potential fish stocks were identified by the analysis of Sr:Ca otoliths-edge ratios: one in the Valencian Gulf, DE-AV areas presented similar ratios, and the other in the southern location, SP (higher Sr:Ca values). Mugil cephalus presented diverse life patterns on the Valencian Community Mediterranean coast. Different strategies could be identified by the used methodology: some particular to an area (Type IV-SP); others

  8. Otolith growth of Springer's demoiselle, Chrysiptera springeri (Pomacentridae, Allen & Lubbock), on a protected and non-protected coral reef

    DEFF Research Database (Denmark)

    Retzel, A.; Hansen, A.D.; Grønkjær, P.

    2007-01-01

    The structural complexity of coral reefs is important for their function as shelter and feeding habitats for coral reef fishes, but physical disturbance by human activities often reduce complexity of the reefs by selectively destroying fragile and more complex coral species. The damselfish Springer......'s demoiselle Chrysiptera springeri primarily utilize complex coral heads for shelter and are hence vulnerable to human disturbance. In order to evaluate the potential effect of habitat degradation on juvenile fish growth, coral reef cover, fish age at settling and otolith growth, juvenile Springer's demoiselle...... was investigated on a protected and non-protected coral reef in Darvel Bay, Borneo. The protected reef had higher coverage of complex branching corals and exhibited a more complex 3-dimensional structure than the non-protected reef. Springer's demoiselle settled at the same age on non-protected and protected reefs...

  9. AFSC/RACE/EcoFOCI - Otolith measurements and analyses performed in support of FOCI assessment surveys and ecosystem observations in the Bering, Beaufort, and Chukchi Seas and the Gulf of Alaska. 1995 - Present

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Otolith data are collected to measure age and growth of larval pollock. They are used to determine whether growth rate, hatch data and/or temperature influence fish...

  10. Effects of ocean acidification on growth and otolith condition of juvenile scup, Stenotomus chrysops from laboratory experiment studies from 2011-08-24 to 2011-10-19 (NODC Accession 0117506)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This archival package contains laboratory experiment data that were collected to examine the effects of elevated levels of CO2 on the growth, survival, otolith (ear...

  11. Dual control of pcdh8l/PCNS expression and function in Xenopus laevis neural crest cells by adam13/33 via the transcription factors tfap2α and arid3a

    Science.gov (United States)

    Khedgikar, Vikram; Abbruzzese, Genevieve; Mathavan, Ketan; Szydlo, Hannah; Cousin, Helene

    2017-01-01

    Adam13/33 is a cell surface metalloprotease critical for cranial neural crest (CNC) cell migration. It can cleave multiple substrates including itself, fibronectin, ephrinB, cadherin-11, pcdh8 and pcdh8l (this work). Cleavage of cadherin-11 produces an extracellular fragment that promotes CNC migration. In addition, the adam13 cytoplasmic domain is cleaved by gamma secretase, translocates into the nucleus and regulates multiple genes. Here, we show that adam13 interacts with the arid3a/dril1/Bright transcription factor. This interaction promotes a proteolytic cleavage of arid3a and its translocation to the nucleus where it regulates another transcription factor: tfap2α. Tfap2α in turn activates multiple genes including the protocadherin pcdh8l (PCNS). The proteolytic activity of adam13 is critical for the release of arid3a from the plasma membrane while the cytoplasmic domain appears critical for the cleavage of arid3a. In addition to this transcriptional control of pcdh8l, adam13 cleaves pcdh8l generating an extracellular fragment that also regulates cell migration. PMID:28829038

  12. Whitemouth croaker, Micropogonias furnieri, trapped in a freshwater coastal lagoon: a natural comparison of freshwater and marine influences on otolith chemistry

    Directory of Open Access Journals (Sweden)

    Cristiano Q. de Albuquerque

    Full Text Available Strontium and barium incorporation into otoliths was compared between whitemouth croaker, Micropogonias furnieri, collected from an entrapped freshwater population (Mirim Lagoon and a normal marine/estuarine population in southern Brazil. Chemical analysis was performed using LA-ICPMS with the objective of validating the effects of marine and freshwater environments on Sr and Ba incorporation as a basis for further investigation of marine and freshwater connectivity of M. furnieri. The freshwater population was dominated by older fish with mean ±SD age of 34±1 y, whereas the coastal samples were dominated by younger fish of 14±7 y. Comparison of strontium and barium incorporation among otolith life-history profiles indicated significantly higher barium and lower strontium for the freshwater population compared to the marine population. Furthermore, comparison of otolith material deposited in the freshwater, estuarine and marine life-history phases demonstrated clear differences among these environments. Mean concentrations of strontium and barium in otoliths of M. furnieri were respectively 710 and 112 µg g-1 for freshwater, 2069 and 16.7 µg g-1 for estuarine, and 2990 and 2.7 µg g-1 for marine life-history phases. Barium concentrations in otoliths from the freshwater population of M. furnieri appeared high relative to other freshwater species. Strontium levels across life-history profiles of marine fish increased with age from 2000 to 2900 µg g-1, possibly indicating more time spent in marine than estuarine waters with age. In contrast, for the freshwater population, strontium levels decreased during the first year of life approximately to 700 µg g-1, and remained low and stable thereafter, consistent with the early life-history occurring in an estuarine environment prior to entrapment in Mirim Lagoon. The results confirm the strong and opposite effects of marine and freshwater environments on incorporation of barium and strontium into

  13. 87Sr/86Sr isotope ratio analysis by laser ablation MC-ICP-MS in scales, spines, and fin rays as a nonlethal alternative to otoliths for reconstructing fish life history

    Science.gov (United States)

    Willmes, Malte; Glessner, Justin J. G.; Carleton, Scott A.; Gerrity, Paul C.; Hobbs, James A.

    2016-01-01

    Strontium isotope ratios (87Sr/86Sr) in otoliths are a well-established tool to determine origins and movement patterns of fish. However, otolith extraction requires sacrificing fish, and when working with protected or endangered species, the use of nonlethal samples such as scales, spines, and fin rays is preferred. Unlike otoliths that are predominantly aragonite, these tissues are composed of biological apatite. Laser ablation multicollector inductively coupled plasma mass spectrometry (LA-MC-ICP-MS) analysis of biological apatite can induce significant interference on mass 87, causing inaccurate 87Sr/86Sr measurements. To quantify this interference, we applied LA-MC-ICP-MS to three marine samples (white seabass (Atractoscion nobilis) otolith; green sturgeon (Acipenser medirostris) pectoral fin ray; salmon shark (Lamna ditropis) tooth), and freshwater walleye (Sander vitreus) otoliths, scales, and spines). Instrument conditions that maximize signal intensity resulted in elevated 87Sr/86Sr isotope ratios in the bioapatite samples, related to a polyatomic interference (40Ca31P16O, 40Ar31P16O). Retuning instrument conditions to reduce oxide levels removed this interference, resulting in accurate 87Sr/86Sr ratios across all tissue samples. This method provides a novel, nonlethal alternative to otolith analysis to reconstruct fish life histories.

  14. Evaluation of otolith shape as a tool for stock discrimination in marine fishes using Baltic Sea cod as a case study

    DEFF Research Database (Denmark)

    Hüssy, Karin; Mosegaard, Henrik; Albertsen, Christoffer Moesgaard

    2016-01-01

    into the alternatestock. Classification criteria selected by Monte Carlo runs of Linear Discriminant Analysis were capturedby otolith area and 20 Elliptic Fourier Descriptors of primarily low frequency harmonics. Classificationsuccess was considerably lower when using a baseline of spawning individuals only, compared......In the Western Baltic Sea two genetically distinct cod stocks “Eastern Baltic cod” and “Western Balticcod” occur with considerable mixing of stocks. In this study we evaluated the applicability of otolithshape analysis for classification of individuals caught in the mixed stock cod fishery, using...... SNP (singlenucleotide polymorphism) based genetic assignment of otolith shape baselines. We further developeda management aimed approach for mixed stock assignment by robust stochastic baseline selection andposterior bias correction by individual reassignment of the least likely classifications...

  15. Determination of age and growth of the striped seabream Lithognathus mormyrus (Sparidae, in the Canary archipelago by otolith readings and backcalculation

    Directory of Open Access Journals (Sweden)

    José G. Pajuelo

    2002-03-01

    Full Text Available The age and growth of the striped seabream Lithognathus mormyrus caught off the Canary Islands (central-east Atlantic from January to December 1999 were studied. A total of 496 individuals, ranging in size between 113 and 350 mm total length, were examined. Otoliths clearly showed the ring pattern common to teleost fishes. One year´s growth was made up of one opaque and one translucent ring. The opaque ring was deposited during the summer months and the translucent one during the winter months. Fish aged 0-8 years old were found. The von Bertalanffy growth parameters for all fish were: L?=427 mm, k=0.19 year-1, and t0=1.46 year. The otolith readings for estimating age and growth were confirmed by using the backcalculation method.

  16. Migratory life history of European eel Anguilla anguilla from freshwater regions of the River Asi, southern Turkey and their high otolith Sr:Ca ratios.

    Science.gov (United States)

    Lin, Y-J; Yalçin-Özdilek, S; Iizuka, Y; Gümüş, A; Tzeng, W-N

    2011-03-01

    Otolith Sr:Ca ratios from 32 of 34 European eel Anguilla anguilla collected from three freshwater sites in the River Asi, southern Turkey, indicated that they were resident in fresh water without apparent exposure to salt water since the elver stage. The Sr:Ca ratio criterion indicative of residence in fresh water was more than twice that of values from other European countries. Otolith Sr:Ca ratios of A. anguilla from fresh waters can vary among regions, possibly reflecting regional-specific water chemistry. Hence, the use of Sr:Ca ratios determined in one region to interpret results from a different region might lead to misclassification of migratory life-history types. © 2011 The Authors. Journal of Fish Biology © 2011 The Fisheries Society of the British Isles.

  17. Application of otolith shape analysis for stock discrimination and species identification of five goby species (Perciformes: Gobiidae) in the northern Chinese coastal waters

    Science.gov (United States)

    Yu, Xin; Cao, Liang; Liu, Jinhu; Zhao, Bo; Shan, Xiujuan; Dou, Shuozeng

    2014-09-01

    We tested the use of otolith shape analysis to discriminate between species and stocks of five goby species ( Ctenotrypauchen chinensis, Odontamblyopus lacepedii, Amblychaeturichthys hexanema, Chaeturichthys stigmatias, and Acanthogobius hasta) found in northern Chinese coastal waters. The five species were well differentiated with high overall classification success using shape indices (83.7%), elliptic Fourier coefficients (98.6%), or the combination of both methods (94.9%). However, shape analysis alone was only moderately successful at discriminating among the four stocks (Liaodong Bay, LD; Bohai Bay, BH; Huanghe (Yellow) River estuary HRE, and Jiaozhou Bay, JZ stocks) of A. hasta (50%-54%) and C. stigmatias (65.7%-75.8%). For these two species, shape analysis was moderately successful at discriminating the HRE or JZ stocks from other stocks, but failed to effectively identify the LD and BH stocks. A large number of otoliths were misclassified between the HRE and JZ stocks, which are geographically well separated. The classification success for stock discrimination was higher using elliptic Fourier coefficients alone (70.2%) or in combination with shape indices (75.8%) than using only shape indices (65.7%) in C. stigmatias whereas there was little difference among the three methods for A. hasta. Our results supported the common belief that otolith shape analysis is generally more effective for interspecific identification than intraspecific discrimination. Moreover, compared with shape indices analysis, Fourier analysis improves classification success during inter- and intra-species discrimination by otolith shape analysis, although this did not necessarily always occur in all fish species.

  18. THE CONTRIBUTION OF SPRINGTIME AND AUTUMN GLASS EELS (ANGUILLA ANGUILLA TO STOCK : RESULTS BASED ON OTOLITH MORPHOMETRY.

    Directory of Open Access Journals (Sweden)

    BRIAND C.

    2003-07-01

    Full Text Available A double mark, called a transition ring, or elver mark, was identifiable in light microscopy on otoliths of young yellow eels. In the Vilaine watershed, the radius of this mark decreased from 178 μm in yellow eels corresponding to glass eels arriving in autumn 1997 to 163 μm in yellow eels arriving in spring 1998. The mean transition ring radius of the freshwater eel population in the Vilaine river had an intermediate value between spring and autumn recruits. This implies that it consisted of a mixture of spring and autumn recruits. In the Vilaine estuary and the Frémur populations, the mean radius of the transition rings was close to the autumn one. The springtime recruits formed 68 % of freshwater and 15 % of estuarine population in the Vilaine for the 1998 cohort. This result was in sharp contrast with the available assessments of recruitment, which both in estuary and in the fluvial part of the watershed, were dominated by spring recruits. This contrast is possibly the consequence of density-dependent mortality, which would have been particularly important in springtime for glass eels whose migration was inhibited by the dam.

  19. Cadherin-11 Regulation of Fibrosis through Modulation of Epithelial-to-Mesenchymal Transition: Implications for Pulmonary Fibrosis in Scleroderma

    Science.gov (United States)

    2016-05-01

    deficient mice (KO) exposed to BLM are shown in the right panels. Examination of lung histology through alpha smooth muscle actin IHC (top) and beta...fibrosis. We have previously reported that Cad11 expression is increased in fibrotic tissues from lungs of patients with idiopathic pulmonary fibrosis...figure displays representative histology of lungs from wild type (WT) mice treated with PBS (left) and bleomycin (BLM, middle). Cad11 deficient mice

  20. Migratory patterns of exotic brown trout Salmo trutta in south-western Hokkaido, Japan, on the basis of otolith Sr:Ca ratios and acoustic telemetry.

    Science.gov (United States)

    Honda, K; Arai, T; Kobayashi, S; Tsuda, Y; Miyashita, K

    2012-02-01

    Acoustic telemetry and microchemical analysis of otolith strontium-calcium ratios were used to evaluate how exotic brown trout Salmo trutta have responded to Japanese riverine environments of south-western Hokkaido by observing their migratory patterns. The existence of anadromous S. trutta was also verified. Most S. trutta caught in rivers for otolith analysis were freshwater residents (95·6%), whereas those caught in the sea were mainly smolts (91·3%), which had just migrated from rivers during spring. Anadromous S. trutta (n = 6) were captured in rivers and in the sea, confirming the existence of mature pre- and post-spawning fish. According to telemetry results, both mature and immature S. trutta used the river in winter, and their estimated sea-run timings showed individual differences. Through the combination of these two methods, migratory patterns on various spatio-temporal scales were observed. This first documentation of the presence of both male and female anadromous S. trutta in the same region within Japan indicated the risk of further colonization of exotic S. trutta via oceanic migration. © 2012 The Authors. Journal of Fish Biology © 2012 The Fisheries Society of the British Isles.

  1. Gentamicin alters nitric oxide production in semicircular canals and otolith organs.

    Science.gov (United States)

    Helling, Kai; Heinrich, Ulf-Rüdiger; Heusgen, Lukas; Brieger, Jürgen; Schmidtmann, Irene; Li, Huige; Mann, Wolf J

    2010-10-01

    Intratympanic application of gentamicin is an important therapeutic option to control vertigo spells in Ménière's disease. Low doses eliminate the function of semicircular canal ampullae (SCCA) and saccule in most patients, although utricular function is maintained in many cases. Local alteration in free radical production might be responsible for these differences. Therefore, the gentamicin-induced nitric oxide (NO) production was determined in an animal model using separate organ cultures of SCCA, saccule, and utricle. Prospective pilot study in male guinea pigs. SCCA, saccule, and utricle of 28 guinea pigs were isolated and incubated separately for 6 hours in cell culture medium. Gentamicin was administered in two different concentrations (0.4 mg/mL and 0.8 mg/mL) to organ cultures of 16 animals. Tissues from 12 animals were used as controls. Nitric oxide was quantified by chemiluminescence. Gentamicin led to an NO increase of about 70% in the saccule, an NO reduction of more than 70% in SCCA, and an NO reduction of 36% in the utricle. The selective effects of gentamicin on the NO production in the different sensory areas of the vestibular organ have to be taken into account in the therapy of Ménière's disease.

  2. Intrinsically disordered and pliable Starmaker-like protein from medaka (Oryzias latipes) controls the formation of calcium carbonate crystals.

    Science.gov (United States)

    Różycka, Mirosława; Wojtas, Magdalena; Jakób, Michał; Stigloher, Christian; Grzeszkowiak, Mikołaj; Mazur, Maciej; Ożyhar, Andrzej

    2014-01-01

    Fish otoliths, biominerals composed of calcium carbonate with a small amount of organic matrix, are involved in the functioning of the inner ear. Starmaker (Stm) from zebrafish (Danio rerio) was the first protein found to be capable of controlling the formation of otoliths. Recently, a gene was identified encoding the Starmaker-like (Stm-l) protein from medaka (Oryzias latipes), a putative homologue of Stm and human dentine sialophosphoprotein. Although there is no sequence similarity between Stm-l and Stm, Stm-l was suggested to be involved in the biomineralization of otoliths, as had been observed for Stm even before. The molecular properties and functioning of Stm-l as a putative regulatory protein in otolith formation have not been characterized yet. A comprehensive biochemical and biophysical analysis of recombinant Stm-l, along with in silico examinations, indicated that Stm-l exhibits properties of a coil-like intrinsically disordered protein. Stm-l possesses an elongated and pliable structure that is able to adopt a more ordered and rigid conformation under the influence of different factors. An in vitro assay of the biomineralization activity of Stm-l indicated that Stm-l affected the size, shape and number of calcium carbonate crystals. The functional significance of intrinsically disordered properties of Stm-l and the possible role of this protein in controlling the formation of calcium carbonate crystals is discussed.

  3. Responses to rotating linear acceleration vectors considered in relation to a model of the otolith organs. [human oculomotor response to transverse acceleration stress

    Science.gov (United States)

    Benson, A. J.; Barnes, G. R.

    1973-01-01

    Human subjects were exposed to a linear acceleration vector that rotated in the transverse plane of the skull without angular counterrotation. Lateral eye movements showed a sinusoidal change in slow phase velocity and an asymmetry or bias in the same direction as vector rotation. A model is developed that attributes the oculomotor response to otolithic mechanisms. It is suggested that the bias component is the manifestation of torsion of the statoconial plaque relative to the base of the utricular macula and that the sinusoidal component represents the translational oscillation of the statoconia. The model subsumes a hypothetical neural mechanism which allows x- and y-axis accelerations to be resolved. Derivation of equations of motion for the statoconial plaque in torsion and translation, which take into account forces acting in shear and normal to the macula, yield estimates of bias and sinusoidal components that are in qualitative agreement with the diverse experimental findings.

  4. Habitat use and migratory behaviour of pikeperch Sander lucioperca in Lithuanian and Latvian waters as inferred from otolith Sr:Ca ratios

    Science.gov (United States)

    Ložys, Linas; Shiao, Jen-Chieh; Iizuka, Yoshiyuki; Minde, Atis; Pūtys, Žilvinas; Jakubavičiūtė, Eglė; Dainys, Justas; Gorfine, Harry; Tzeng, Wann-Nian

    2017-11-01

    Determination of the geographic boundaries that define a stock is a key challenge in fisheries management. Acquiring an understanding of spatial distribution and migration patterns of pikeperch Sander lucioperca populations in the south-eastern Baltic Sea region would help to delineate the stocks and contribute towards sustainable exploitation of the population. In this study, habitat use and migratory behaviour of S. lucioperca were inferred from otolith Sr:Ca ratios obtained via an Electron Probe Micro-Analyzer. S. lucioperca collected from the inland Kaunas City water reservoir, where downstream migration is precluded by a hydro-power plant, consistently showed a freshwater signature in their otoliths throughout their life history. In contrast, those collected from the Baltic Sea and Curonian Lagoon in Lithuania, and the lower reaches of the Daugava River in Latvia had ratios indicative of movement between fresh and brackish water habitats. Although S. lucioperca can inhabit brackish water bodies, they predominantly reside and reproduce in freshwater systems. It is thought that periodic post-spawning migration to the sea during spring is related to better foraging conditions and perhaps as a strategy for shedding ectoparasites. Currently, catch quotas apply only to those S. lucioperca taken from the Curonian Lagoon and not the Baltic Sea. Frequent migration between freshwater habitats and the Baltic Sea suggest that S. lucioperca stocks from a given river/estuary system should be considered as a single management unit despite individual differences in migratory behaviour. The extent to which migration into the Baltic Sea could potentially compromise the effectiveness of catch quotas was the main issue which initiated this study.

  5. Relationships between water, otolith, and scale chemistries of westslope cutthroat trout from the Coeur d'Alene River, Idaho: the potential application of hard-part chemistry to describe movements in freshwater

    Science.gov (United States)

    Brian K. Wells; Bruce E. Rieman; James L. Clayton; Donna L. Horan; Cynthia M. Jones

    2003-01-01

    We quantified Mg:Ca, Mn:Ca, Sr:Ca, and Ba:Ca molar ratios from an area representing the summer 2000 growth season on otoliths and scales from 1-year-old westslope cutthroat trout Oncorhyncus clarki lewisi collected from three streams in the Coeur d'Alene River, Idaho, system. We also quantified Mg:Ca, Sr:Ca, and Ba:Ca molar ratios in the water...

  6. Otolith reading and multi-model inference for improved estimation of age and growth in the gilthead seabream Sparus aurata (L.)

    Science.gov (United States)

    Mercier, Lény; Panfili, Jacques; Paillon, Christelle; N'diaye, Awa; Mouillot, David; Darnaude, Audrey M.

    2011-05-01

    Accurate knowledge of fish age and growth is crucial for species conservation and management of exploited marine stocks. In exploited species, age estimation based on otolith reading is routinely used for building growth curves that are used to implement fishery management models. However, the universal fit of the von Bertalanffy growth function (VBGF) on data from commercial landings can lead to uncertainty in growth parameter inference, preventing accurate comparison of growth-based history traits between fish populations. In the present paper, we used a comprehensive annual sample of wild gilthead seabream ( Sparus aurata L.) in the Gulf of Lions (France, NW Mediterranean) to test a methodology improving growth modelling for exploited fish populations. After validating the timing for otolith annual increment formation for all life stages, a comprehensive set of growth models (including VBGF) were fitted to the obtained age-length data, used as a whole or sub-divided between group 0 individuals and those coming from commercial landings (ages 1-6). Comparisons in growth model accuracy based on Akaike Information Criterion allowed assessment of the best model for each dataset and, when no model correctly fitted the data, a multi-model inference (MMI) based on model averaging was carried out. The results provided evidence that growth parameters inferred with VBGF must be used with high caution. Hence, VBGF turned to be among the less accurate for growth prediction irrespective of the dataset and its fit to the whole population, the juvenile or the adult datasets provided different growth parameters. The best models for growth prediction were the Tanaka model, for group 0 juveniles, and the MMI, for the older fish, confirming that growth differs substantially between juveniles and adults. All asymptotic models failed to correctly describe the growth of adult S. aurata, probably because of the poor representation of old individuals in the dataset. Multi

  7. Age estimations of wild pallid sturgeon (Scaphirhynchus albus, Forbes & Richardson 1905) based on pectoral fin spines, otoliths and bomb radiocarbon: inferences on recruitment in the dam-fragmented Missouri River

    Science.gov (United States)

    Braaten, P. J.; Campana, S. E.; Fuller, D. B.; Lott, R. D.; Bruch, R. M.; Jordan, G. R.

    2015-01-01

    An extant stock of wild pallid sturgeon Scaphirhynchus albus persists in the fragmented upper Missouri River basin of Montana and North Dakota. Although successful spawning and hatch of embryos has been verified, long-term catch records suggest that recruitment has not occurred for several decades as the extant stock lacks juvenile size classes and is comprised exclusively of large, presumably old individuals. Ages of 11 deceased (death years 1997–2007) wild S. albus (136–166 cm fork length) were estimated based on pectoral fin spines, sagittal otoliths and bomb radiocarbon (14C) assays of otoliths to test the hypothesis that members of this stock are old and to provide inferences on recruitment years that produced the extant stock. Age estimations based on counts of presumed annuli were about 2 years greater for otoliths (mean = 51 years, range = 43–57 years) than spines (mean = 49 years, range = 37–59 years). Based on 14C assays, confirmed birth years for all individuals occurred prior to 1957, thus establishing known longevity of at least 50 years. Estimated age based on presumed otolith annuli for one S. albus was validated to at least age 49. Although 14C assays confirmed pre-1957 birth years for all S. albus, only 56% of estimated ages from spines and 91% of estimated ages from otoliths depicted pre-1957 birth years. Both ageing structures were subject to under-ageing error (up to 15 years). Lack of or severe curtailment of S. albus recruitment in the upper Missouri River basin since the mid-1950s closely parallels the 1953–1957 timeframe when a mainstem reservoir was constructed and started to fill. This reservoir may function as a system-wide stressor to diminish recruitment success of S. albus in the upper Missouri River basin.

  8. Spatio-temporal variability in movement, age, and growth of mountain whitefish (Prosopium williamsoni) in a river network based upon PIT tagging and otolith chemistry

    Science.gov (United States)

    Benjamin, Joseph R.; Wetzel, Lisa A.; Martens, Kyle D.; Larsen, Kimberly; Connolly, Patrick J.

    2013-01-01

    Connectivity of river networks and the movements among habitats can be critical for the life history of many fish species, and understanding of the patterns of movement is central to managing populations, communities, and the landscapes they use. We combined passive integrated transponder tagging over 4 years and strontium isotopes in otoliths to demonstrate that 25% of the mountain whitefish (Prosopium williamsoni) sampled moved between the Methow and Columbia rivers, Washington, USA. Seasonal migrations downstream from the Methow River to the Columbia River to overwinter occurred in autumn and upstream movements in the spring. We observed migration was common during the first year of life, with migrants being larger than nonmigrants. However, growth between migrants and nonmigrants was similar. Water temperature was positively related to the proportion of migrants and negatively related to the timing of migration, but neither was related to discharge. The broad spatio-temporal movements we observed suggest mountain whitefish, and likely other nonanadromous fish, require distant habitats and also suggests that management and conservation strategies to keep connectivity of large river networks are imperative.

  9. Immagine della crisi / Crisi dell'immagine. Critica all'egemonia culturale del realismo e diritto all'opacità in Hydra Decapita (2011, un film saggio di The Otolith Group

    Directory of Open Access Journals (Sweden)

    Beatrice Ferrara

    2015-12-01

    Full Text Available This article reflects on the ways in which the relation between crisis and imaginary is articulated in Hydra Decapita, a 2011 essay-film by the British art collective The Otolith Group. Hydra Decapita is an imaged-based reflection arguing for the biopolitical character of the global economic crisis erupted in 2008 and of its representations in the media. By deploying a Cultural Studies-oriented interdisciplinary approach to the artwork – drawing its methodology from visual studies, critical theory and post-colonial studies – the article interrogates the limits and potentialities of Hydra Decapita’s conceptual kernel and aesthetic language.

  10. Calbindin and parvalbumin are early markers of non-mitotically regenerating hair cells in the bullfrog vestibular otolith organs

    Science.gov (United States)

    Steyger, P. S.; Burton, M.; Hawkins, J. R.; Schuff, N. R.; Baird, R. A.

    1997-01-01

    Earlier studies have demonstrated hair cell regeneration in the absence of cell proliferation, and suggested that supporting cells could phenotypically convert into hair cells following hair cell loss. Because calcium-binding proteins are involved in gene up-regulation, cell growth, and cell differentiation, we wished to determine if these proteins were up-regulated in scar formations and regenerating hair cells following gentamicin treatment. Calbindin and parvalbumin immunolabeling was examined in control or gentamicin-treated (GT) bullfrog saccular and utricular explants cultured for 3 days in amphibian culture medium or amphibian culture medium supplemented with aphidicolin, a blocker of nuclear DNA replication in eukaryotic cells. In control cultures, calbindin and parvalbumin immunolabeled the hair bundles and, less intensely, the cell bodies of mature hair cells. In GT or mitotically-blocked GT (MBGT) cultures, calbindin and parvalbumin immunolabeling was also seen in the hair bundles, cuticular plates, and cell bodies of hair cells with immature hair bundles. Thus, these antigens were useful markers for both normal and regenerating hair cells. Supporting cell immunolabeling was not seen in control cultures nor in the majority of supporting cells in GT cultures. In MBGT cultures, calbindin and parvalbumin immunolabeling was up-regulated in the cytosol of single supporting cells participating in scar formations and in supporting cells with hair cell-like characteristics. These data provide further evidence that non-mitotic hair cell regeneration in cultures can be accomplished by the conversion of supporting cells into hair cells.

  11. The study and comparison of heavy metals concentration (Nickel, Lead, Cadmium and Zinc in the muscle of Otolithes ruber, Parastromateus niger, Scomberomorus commerson and Sphyraena jello from Chabahar area in summer

    Directory of Open Access Journals (Sweden)

    E. Shahri

    2017-07-01

    Full Text Available The heavy metals are from the pollutants which create too much problems in aquatic ecosystems for aquatics and human. This study was done concentration of heavy metals Nickle, Cadmium, Lead  and  Zinc and risk assessment in the muscle of Otolithes ruber, Parastromateus niger, Scomberomorus commerson and Sphyraena jello in 2013. Ninety six  samples of fishes was prepared of coastal and marine from the Chabahar, Iran. Metals were extracted from the tissues using wet Digestion method and concentration of the heavy metals were measured by Atomic Absorption Spectrophotometer Younglin AAS8020. Concentration of Cd was in Parastromateus niger (0.0450 mg Kg-1 higher than other species. Also, the lowest Concentration of this element was in Otolithes ruber and Scomberomorus commerson (0.0150 mg Kg-1. Concentration of Pb was in Sphyraena jello (0.0125 mg Kg-1 lower than other species. Concentration of Ni was in Sphyraena jello (4.1800 mg Kg-1 higher than other species. Also, the lowest Concentration of this element was in Scomberomorus commerson (0.0150 mg Kg-1. Concentration of Zn was in Sphyraena jello (0.5450 mg Kg-1 higher than other species. Also, the lowest Concentration of this element was in Scomberomorus commerson (0.0150 mg Kg-1. Concentration of Cd, Pb and Zn was lower than comparison of FAO, WHO, UKMAFF, NHMRC and FDA. Concentration of Ni was higher than comparison ofGlobal Standards. According to the results, the amount of heavy metals in muscle of fishes in the study not take any risks for human consumption.

  12. Otolith micro-structure analysis of rainbow trout alevins (Oncorhynchus mykiss under rearing conditions Análisis de la micro-estructura de otolitos en alevines de trucha arcoiris (Oncorhynchus mykiss en cautiverio

    Directory of Open Access Journals (Sweden)

    Guillermo Moyano

    2012-09-01

    Full Text Available Otolith microstructure (MO analysis was used to back-calculate growth patterns from hatching to the yolk-sac absorption in Rainbow trout alevins (Oncorhynchus mykiss, under experimental conditions, from winter to spring in Central-Chile. MO showed the following main features: (i occurrences of multiple primordia in the central region of otolith (MP; (ii several increments (22 ± 3 rings before a prominent hatch check surrounding MP and (iii existence of a very distinctive check associated to yolk-sac absorption. Further findings were the validation of daily periodicity of micro-increments and a significant linear relationship (P La micro-estructura de otolitos (MO fue utilizada para retro-calcular los patrones de crecimiento, desde la eclosión hasta la absorción del saco vitelino, en alevines de trucha arcoiris (Oncorhynchus mykiss, en la zona central de Chile. La MO mostró tres características principales: (i ocurrencia de múltiples primordios en la región central de los otolitos (MP, (ii formación de varios micro-incrementos antes de la eclosión (22 ± 3 micro-incrementos (iii y existencia de una marca distintiva correspondiente a la absorción del saco vitelino. Otros resultados fueron la validación de la periodicidad diaria de micro-incrementos y la existencia de una relación lineal significativa (P < 0,001; r2 = 0,91 entre la longitud máxima del otolito (LMO y la longitud total de los alevines (L T. La relación lineal L MO-L T validó el uso del método de intercepto biológico, para retro-calcular las tasas diarias de crecimiento (TDC. Las TDC mostraron una tendencia decreciente desde la eclosión hasta 6 días después de la absorción del saco vitelino (16 ± 1 días, las TDC variaron desde los 0,22 mm d-1 a los 0,34 mm d-1 (0,30 ± 0,037. La MO demostró ser una herramienta efectiva para el análisis retrospectivo de los patrones de crecimiento en alevins una vez absorbido su saco vitelino.

  13. Controlling

    OpenAIRE

    Tůmová, Jana

    2009-01-01

    The diploma thesis focuses on the problems of operational controllership and the instruments used for their solution. In connection with these issues the thesis also defines the role of the controller, in particular his authorities and responsibilities. The theoretical part of the work looks at the academic conception of controlleship. The practical part describes the main functions, duties, activities and the system of cooperation in between controllership and other departments in particular...

  14. Postural Control in Bilateral Vestibular Failure: Its Relation to Visual, Proprioceptive, Vestibular, and Cognitive Input.

    Science.gov (United States)

    Sprenger, Andreas; Wojak, Jann F; Jandl, Nico M; Helmchen, Christoph

    2017-01-01

    Patients with bilateral vestibular failure (BVF) suffer from postural and gait unsteadiness with an increased risk of falls. The aim of this study was to elucidate the differential role of otolith, semicircular canal (SSC), visual, proprioceptive, and cognitive influences on the postural stability of BVF patients. Center-of-pressure displacements were recorded by posturography under six conditions: target visibility; tonic head positions in the pitch plane; horizontal head shaking; sensory deprivation; dual task; and tandem stance. Between-group analysis revealed larger postural sway in BVF patients on eye closure; but with the eyes open, BVF did not differ from healthy controls (HCs). Head tilts and horizontal head shaking increased sway but did not differ between groups. In the dual task condition, BVF patients maintained posture indistinguishable from controls. On foam and tandem stance, postural sway was larger in BVF, even with the eyes open. The best predictor for the severity of bilateral vestibulopathy was standing on foam with eyes closed. Postural control of our BVF was indistinguishable from HCs once visual and proprioceptive feedback is provided. This distinguishes them from patients with vestibulo-cerebellar disorders or functional dizziness. It confirms previous reports and explains that postural unsteadiness of BVF patients can be missed easily if not examined by conditions of visual and/or proprioceptive deprivation. In fact, the best predictor for vestibular hypofunction (VOR gain) was examining patients standing on foam with the eyes closed. Postural sway in that condition increased with the severity of vestibular impairment but not with disease duration. In the absence of visual control, impaired otolith input destabilizes BVF with head retroflexion. Stimulating deficient SSC does not distinguish patients from controls possibly reflecting a shift of intersensory weighing toward proprioceptive-guided postural control. Accordingly, proprioceptive

  15. Postural Control in Bilateral Vestibular Failure: Its Relation to Visual, Proprioceptive, Vestibular, and Cognitive Input

    Science.gov (United States)

    Sprenger, Andreas; Wojak, Jann F.; Jandl, Nico M.; Helmchen, Christoph

    2017-01-01

    Patients with bilateral vestibular failure (BVF) suffer from postural and gait unsteadiness with an increased risk of falls. The aim of this study was to elucidate the differential role of otolith, semicircular canal (SSC), visual, proprioceptive, and cognitive influences on the postural stability of BVF patients. Center-of-pressure displacements were recorded by posturography under six conditions: target visibility; tonic head positions in the pitch plane; horizontal head shaking; sensory deprivation; dual task; and tandem stance. Between-group analysis revealed larger postural sway in BVF patients on eye closure; but with the eyes open, BVF did not differ from healthy controls (HCs). Head tilts and horizontal head shaking increased sway but did not differ between groups. In the dual task condition, BVF patients maintained posture indistinguishable from controls. On foam and tandem stance, postural sway was larger in BVF, even with the eyes open. The best predictor for the severity of bilateral vestibulopathy was standing on foam with eyes closed. Postural control of our BVF was indistinguishable from HCs once visual and proprioceptive feedback is provided. This distinguishes them from patients with vestibulo-cerebellar disorders or functional dizziness. It confirms previous reports and explains that postural unsteadiness of BVF patients can be missed easily if not examined by conditions of visual and/or proprioceptive deprivation. In fact, the best predictor for vestibular hypofunction (VOR gain) was examining patients standing on foam with the eyes closed. Postural sway in that condition increased with the severity of vestibular impairment but not with disease duration. In the absence of visual control, impaired otolith input destabilizes BVF with head retroflexion. Stimulating deficient SSC does not distinguish patients from controls possibly reflecting a shift of intersensory weighing toward proprioceptive-guided postural control. Accordingly, proprioceptive

  16. A critical period of ear development controlled by distinct populations of ciliated cells in the zebrafish.

    Science.gov (United States)

    Riley, B B; Zhu, C; Janetopoulos, C; Aufderheide, K J

    1997-11-15

    The zebrafish (Danio rerio) is a useful model system for analyzing development of the inner ear. A number of mutations affecting the inner ear have been identified. Here we investigate the initial stages of otolith morphogenesis in wild-type embryos as well as in monolith (mnl) mutant embryos, which fail to form anterior otoliths but otherwise appear normal. Otolith growth is initiated at 18-18.5 h by localized accretion of free-moving precursor particles. This process, referred to as otolith seeding, is regulated by two classes of cilia: First, kinocilia of precociously forming hair cells (tether cells) bind seeding particles, thereby localizing otolith formation. Tether cells usually occur in pairs at the anterior and posterior ends of the ear. Despite the presence of functional kinocilia, tether cells initially appear immature and do not acquire the characteristics of mature hair cells until approximately 21.5 h. Second, beating cilia distributed throughout the ear agitate seeding particles, thereby inhibiting premature agglutination. Constraining particles with laser tweezers caused them to fuse into large untethered masses. Bringing such masses into contact with tethered otoliths caused them to fuse, greatly enhancing otolith growth. Selectively enhancing one otolith greatly inhibited growth of the second, creating an imbalance that persisted for many days. Seeding particles and beating cilia disappear soon after 24 h, and the rate of otolith growth decreases by nearly 90%. In mnl mutant embryos, tethers and beating cilia are distributed normally, but anterior otoliths fail to form in 80-85% of mutant ears. The binding properties of seeding particles appear normal, as shown by their ability to fuse when entrapped by laser tweezers and their binding to posterior tethers. We infer that anterior tethers have a weakened ability to bind seeding particles in mnl embryos. Immobilizing mnl embryos with the anterior end of the ear oriented downward effectively

  17. Otolith output - Project to study alternative life history types of fall Chinook based on otoliths

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The life-history complexity of Snake River fall Chinook salmon has hindered efforts to manage the ESU. In particular, the existence of an overwintering behavior in a...

  18. Cardiovascular and Postural Control Interactions during Hypergravity: Effects on Cerebral Autoregulation in Males and Females

    Science.gov (United States)

    Goswami, Nandu; Blaber, Andrew; Bareille, Marie-Pierre; Beck, Arnaud; Avan, Paul; Bruner, Michelle; Hinghofer-Szalkay, Helmut

    2012-07-01

    Orthostatic intolerance remains a problem upon return to Earth from the microgravity environment of spaceflight. A variety of conditions including hypovolemia, cerebral vasoconstriction, cerebral or peripheral vascular disease, or cardiac arrhythmias may result in syncope if the person remains upright. Current research indicates that there is a greater dependence on visual and somatosensory information at the beginning of space flight with a decreased otolith gain during prolonged space flight (Herault et al., 2002). The goal of the research is to further our understanding of the fundamental adaptive homeostatic mechanisms involved in gravity related changes in cardiovascular and postural function. Cardiovascular, cerebrovascular, and postural sensory motor control systems in male and female participants before, during, and after exposure to graded levels of hyper-G were investigated. Hypotheses: 1) Activation of skeletal muscle pump will be directly related to the degree of orthostatic stress. 2) Simultaneous measurement of heart rate, blood pressure and postural sway will predict cardio-postural stability. Blood pressure and heart rate (means and variability), postural sway, center of pressure (COP), baroreflex function, calf blood flow, middle cerebral artery blood flow, non-invasive intracranial pressure measurements, and two-breath CO2 were measured. Results from the study will be used to provide an integrated insight into mechanisms of cardio-postural control and cerebral autoregulation, which are important aspects of human health in flights to Moon, Mars and distant planets.

  19. Motor Control of Landing from a Jump in Simulated Hypergravity

    Science.gov (United States)

    Gambelli, Clément N.; Theisen, Daniel; Willems, Patrick A.; Schepens, Bénédicte

    2015-01-01

    On Earth, when landing from a counter-movement jump, muscles contract before touchdown to anticipate imminent collision with the ground and place the limbs in a proper position. This study assesses how the control of landing is modified when gravity is increased above 1 g. Hypergravity was simulated in two different ways: (1) by generating centrifugal forces during turns of an aircraft (A300) and (2) by pulling the subject downwards in the laboratory with a Subject Loading System (SLS). Eight subjects were asked to perform counter-movement jumps at 1 g on Earth and at 3 hypergravity levels (1.2, 1.4 and 1.6 g) both in A300 and with SLS. External forces applied to the body, movements of the lower limb segments and muscular activity of 6 lower limb muscles were recorded. Our results show that both in A300 and with SLS, as in 1 g: (1) the anticipation phase is present; (2) during the loading phase (from touchdown until the peak of vertical ground reaction force), lower limb muscles act like a stiff spring, whereas during the second part (from the peak of vertical ground reaction force until the return to the standing position), they act like a compliant spring associated with a damper. (3) With increasing gravity, the preparatory adjustments and the loading phase are modified whereas the second part does not change drastically. (4) The modifications are similar in A300 and with SLS, however the effect of hypergravity is accentuated in A300, probably due to altered sensory inputs. This observation suggests that otolithic information plays an important role in the control of the landing from a jump. PMID:26505472

  20. Motor Control of Landing from a Jump in Simulated Hypergravity.

    Directory of Open Access Journals (Sweden)

    Clément N Gambelli

    Full Text Available On Earth, when landing from a counter-movement jump, muscles contract before touchdown to anticipate imminent collision with the ground and place the limbs in a proper position. This study assesses how the control of landing is modified when gravity is increased above 1 g. Hypergravity was simulated in two different ways: (1 by generating centrifugal forces during turns of an aircraft (A300 and (2 by pulling the subject downwards in the laboratory with a Subject Loading System (SLS. Eight subjects were asked to perform counter-movement jumps at 1 g on Earth and at 3 hypergravity levels (1.2, 1.4 and 1.6 g both in A300 and with SLS. External forces applied to the body, movements of the lower limb segments and muscular activity of 6 lower limb muscles were recorded. Our results show that both in A300 and with SLS, as in 1 g: (1 the anticipation phase is present; (2 during the loading phase (from touchdown until the peak of vertical ground reaction force, lower limb muscles act like a stiff spring, whereas during the second part (from the peak of vertical ground reaction force until the return to the standing position, they act like a compliant spring associated with a damper. (3 With increasing gravity, the preparatory adjustments and the loading phase are modified whereas the second part does not change drastically. (4 The modifications are similar in A300 and with SLS, however the effect of hypergravity is accentuated in A300, probably due to altered sensory inputs. This observation suggests that otolithic information plays an important role in the control of the landing from a jump.

  1. The thermoluminescence of carp otoliths: A fingerprint in ...

    African Journals Online (AJOL)

    use

    2011-12-14

    Dec 14, 2011 ... representative sample, water samples were collected in pre- cleaned HDPE plastic bottles that have been rinsed with sample three times prior to use. Moreover, for metal elemental analysis the samples were acidified to pH <2 soon after field collection because of the problems of absorption or precipitation.

  2. The genetic mineralogical characteristics of fish otoliths and their ...

    African Journals Online (AJOL)

    DR NJ TONUKARI

    2011-05-23

    May 23, 2011 ... information about fish age, feeding and growth history, recruitment and migration, mortality and stock structure, .... INDICATOR OF FISH LIVING HISTORY AND. ENVIRONMENT CHANGE. It is particularly ... temperature in Peru was 3 to 4°C higher than that at present. PROXY FOR FISH STOCKS AND ...

  3. Determining the most suitable method of otolith preparation for ...

    African Journals Online (AJOL)

    Growth zone counts on sectioned lapilli showed the greatest percentage agreement (52%) and highest precision (APE = 4.77%, CV = 6.20%). Growth zone counts were symmetrically distributed between structures (Bowker's tests P > 0.125). Between-reader analysis also showed sectioned lapilli to have the highest ...

  4. Juvenile Salmonid Otolith Data - Ocean Survival of Salmonids

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A study to evaluate the role of changing ocean conditions on growth and survival of juvenile salmon from the Columbia River basin as they enter the Columbia River...

  5. A Preliminary Investigation of Age and Growth of Otolithes ruber ...

    African Journals Online (AJOL)

    Natal, South Africa. The specimens were collected from prawn trawlers that operate off the shallow water Tugela Bank and from a recreational boat fishery in Durban. Estimates of age and growth parameters were based on the examination of ...

  6. Crystal phases of calcium carbonate within otoliths of Cyprinus ...

    African Journals Online (AJOL)

    Significant differences of the dimensions of crystalline cells of vaterites exist between these two localities, which reveals that crystal structure of vaterite polymorphs seem sensitive to water quality and water environment, its crystalline cell dimensions might be a potential proxy for monitoring the change of water quality.

  7. Enrichment of Pb, Hg and Cr in cultured carp otolith

    African Journals Online (AJOL)

    AJL

    2012-01-26

    15% (Rbig and Rsmall represent the replace ions with big and small radius), ion replacement is more likely to happen. When the radius of replacement ions and host ions are almost the same, the resultant is more stable.

  8. [Neuronal plasticity of otolith-related vestibular system].

    Science.gov (United States)

    Lai, Suk-King; Lai, Chun-Hong; Zhang, Fu-Xing; Ma, Chun-Wai; Shum, Daisy K Y; Chan, Ying-Shing

    2008-12-01

    This review focuses on our effort in addressing the development and lesion-induced plasticity of the gravity sensing system. After severance of sensory input from one inner ear, there is a bilateral imbalance in response dynamics and spatial coding behavior between neuronal subpopulations on the two sides. These data provide the basis for deranged spatial coding and motor deficits accompanying unilateral labyrinthectomy. Recent studies have also confirmed that both glutamate receptors and neurotrophin receptors within the bilateral vestibular nuclei are implicated in the plasticity during vestibular compensation and development. Changes in plasticity not only provide insight into the formation of a spatial map and recovery of vestibular function but also on the design of drugs for therapeutic strategies applicable to infants or vestibular disorders such as vertigo and dizziness.

  9. Short Communication Otoliths and vertebrae as potential hard ...

    African Journals Online (AJOL)

    175 cm fork length) collected off the west coast of South Africa were assessed for potential usefulness in age estimation. Growth increments were found on both structures. Comparisons of growth increment counts showed that agreement in the ...

  10. A Preliminary Investigation of Age and Growth of Otolithes

    African Journals Online (AJOL)

    1980) On the interrelationships between natural mortality, growth parameters, and mean environmental temperature in 175 fish stocks. J. Cons. Perm. Int. Explor. Mer. 39: (2): 175-192. Pauly, D. (1984) Fish population dynamics in tropical.

  11. Comparison of vertebrae and otoliths measured directly and from radiographs

    DEFF Research Database (Denmark)

    Pedersen, Jens

    1997-01-01

    from macerated fish. The present study shows that measurement of vertebrae from radiographs of intact fish is a reliable and quick method for estimating the relationship between vertebral length and fish length from a number of reference fish. The relationship between vertebrae size and fish length...

  12. Stiffness control of balance in quiet standing.

    Science.gov (United States)

    Winter, D A; Patla, A E; Prince, F; Ishac, M; Gielo-Perczak, K

    1998-09-01

    model. Sway amplitude decreased as stance width increased, and Ke increased with stance width. A stiffness model would predict sway to vary as Ke-0.5. The experimental results were close to this prediction: sway was proportional to Ke(-0.55). Reactive control of balance was not evident for several reasons. The visual system does not appear to contribute because no significant difference between eyes open and eyes closed results was found at 100% stance width. Vestibular (otolith) and joint proprioceptive reactive control were discounted because the necessary head accelerations, joint displacements, and velocities were well below reported thresholds. Besides, any reactive control would predict that COP would considerably lag (150-250 ms) behind the COM. Because the average COP was only 4 ms delayed behind the COM, reactive control was not evident; this small delay was accounted for by the damping in the tuned mechanical system.

  13. Perancangan Controller

    Directory of Open Access Journals (Sweden)

    Djunaidi Santoso

    2010-12-01

    Full Text Available In making controller, there must be knowledge about component controlling functions that used for controller designing. In the control unit, it needs simple method as micro programming. This micro programming is to create a micro program in binary numbering that used for controlling pin’s component controller and outside the controller. Controller design in general needs several prerequisites, which are digital system and controller and assembly language. 

  14. Control Areas

    Data.gov (United States)

    Department of Homeland Security — This feature class represents electric power Control Areas. Control Areas, also known as Balancing Authority Areas, are controlled by Balancing Authorities, who are...

  15. Dream controller

    Science.gov (United States)

    Cheng, George Shu-Xing; Mulkey, Steven L; Wang, Qiang; Chow, Andrew J

    2013-11-26

    A method and apparatus for intelligently controlling continuous process variables. A Dream Controller comprises an Intelligent Engine mechanism and a number of Model-Free Adaptive (MFA) controllers, each of which is suitable to control a process with specific behaviors. The Intelligent Engine can automatically select the appropriate MFA controller and its parameters so that the Dream Controller can be easily used by people with limited control experience and those who do not have the time to commission, tune, and maintain automatic controllers.

  16. Controllable dose; Dosis controlable

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez R, J.T.; Anaya M, R.A. [ININ, A.P. 18-1027, 11801 Mexico D.F. (Mexico)]. E-mail: jtar@nuclear.inin.mx

    2004-07-01

    With the purpose of eliminating the controversy about the lineal hypothesis without threshold which found the systems of dose limitation of the recommendations of ICRP 26 and 60, at the end of last decade R. Clarke president of the ICRP proposed the concept of Controllable Dose: as the dose or dose sum that an individual receives from a particular source which can be reasonably controllable by means of any means; said concept proposes a change in the philosophy of the radiological protection of its concern by social approaches to an individual focus. In this work a panorama of the foundations is presented, convenient and inconveniences that this proposal has loosened in the international community of the radiological protection, with the purpose of to familiarize to our Mexican community in radiological protection with these new concepts. (Author)

  17. Mosquito Control

    Science.gov (United States)

    ... Protection Agency Search Search Contact Us Share Mosquito Control About Mosquitoes General Information Life Cycle Information from ... Repellent that is Right for You DEET Mosquito Control Methods Success in mosquito control: an integrated approach ...

  18. Birth Control

    Science.gov (United States)

    Birth control, also known as contraception, is designed to prevent pregnancy. Birth control methods may work in a number of different ... eggs that could be fertilized. Types include birth control pills, patches, shots, vaginal rings, and emergency contraceptive ...

  19. Controllable circuit

    DEFF Research Database (Denmark)

    2010-01-01

    signal. The control unit comprises a first signal processing unit, a second signal processing unit, and a combiner unit. The first signal processing unit has an output and is supplied with a first carrier signal and an input signal. The second signal processing unit has an output and is supplied...... with a second carrier signal and the input signal. The combiner unit is connected to the first and second signal processing units combining the outputs of the first and the second signal processing units to form a signal representative of the control signal......A switch-mode power circuit comprises a controllable element and a control unit. The controllable element is configured to control a current in response to a control signal supplied to the controllable element. The control unit is connected to the controllable element and provides the control...

  20. Neurofuzzy Control

    DEFF Research Database (Denmark)

    Jantzen, Jan

    1997-01-01

    These notes are for a course in fuzzy control and neural networks. By neural networks we more precisely mean neurofuzzy systems rather than pure neural network theory. The notes are an extension to the existing notes on fuzzy control (Jantzen, Fuzzy Control, 1994).......These notes are for a course in fuzzy control and neural networks. By neural networks we more precisely mean neurofuzzy systems rather than pure neural network theory. The notes are an extension to the existing notes on fuzzy control (Jantzen, Fuzzy Control, 1994)....

  1. New human-centered linear and nonlinear motion cueing algorithms for control of simulator motion systems

    Science.gov (United States)

    Telban, Robert J.

    While the performance of flight simulator motion system hardware has advanced substantially, the development of the motion cueing algorithm, the software that transforms simulated aircraft dynamics into realizable motion commands, has not kept pace. To address this, new human-centered motion cueing algorithms were developed. A revised "optimal algorithm" uses time-invariant filters developed by optimal control, incorporating human vestibular system models. The "nonlinear algorithm" is a novel approach that is also formulated by optimal control, but can also be updated in real time. It incorporates a new integrated visual-vestibular perception model that includes both visual and vestibular sensation and the interaction between the stimuli. A time-varying control law requires the matrix Riccati equation to be solved in real time by a neurocomputing approach. Preliminary pilot testing resulted in the optimal algorithm incorporating a new otolith model, producing improved motion cues. The nonlinear algorithm vertical mode produced a motion cue with a time-varying washout, sustaining small cues for longer durations and washing out large cues more quickly compared to the optimal algorithm. The inclusion of the integrated perception model improved the responses to longitudinal and lateral cues. False cues observed with the NASA adaptive algorithm were absent. As a result of unsatisfactory sensation, an augmented turbulence cue was added to the vertical mode for both the optimal and nonlinear algorithms. The relative effectiveness of the algorithms, in simulating aircraft maneuvers, was assessed with an eleven-subject piloted performance test conducted on the NASA Langley Visual Motion Simulator (VMS). Two methods, the quasi-objective NASA Task Load Index (TLX), and power spectral density analysis of pilot control, were used to assess pilot workload. TLX analysis reveals, in most cases, less workload and variation among pilots with the nonlinear algorithm. Control input

  2. Helicopter controllability

    OpenAIRE

    Carico, Dean

    1989-01-01

    Approved for public release; distribution is unlimited The concept of helicopter controllability is explained. A background study reviews helicopter development in the U.S. General helicopter configurations, linearized equations of motion, stability, and piloting requirements are discussed. Helicopter flight controls, handling qualities, and associated specification are reviewed. Analytical, simulation and flight test methods for evaluating helicopter automatic flight control systems ar...

  3. Gaining control

    NARCIS (Netherlands)

    Enden, van der E.; Laan, van der R.

    2008-01-01

    The article reports on the efforts of companies to find a solution for tax risk management, tax accounting and being in control. In trying to find a solution, companies work towards an integrated tax control framework (TCF), a tax risk management and control environment embedded in the internal

  4. Spatial cognition, body representation and affective processes: the role of vestibular information beyond ocular reflexes and control of posture.

    Science.gov (United States)

    Mast, Fred W; Preuss, Nora; Hartmann, Matthias; Grabherr, Luzia

    2014-01-01

    A growing number of studies in humans demonstrate the involvement of vestibular information in tasks that are seemingly remote from well-known functions such as space constancy or postural control. In this review article we point out three emerging streams of research highlighting the importance of vestibular input: (1) Spatial Cognition: Modulation of vestibular signals can induce specific changes in spatial cognitive tasks like mental imagery and the processing of numbers. This has been shown in studies manipulating body orientation (changing the input from the otoliths), body rotation (changing the input from the semicircular canals), in clinical findings with vestibular patients, and in studies carried out in microgravity. There is also an effect in the reverse direction; top-down processes can affect perception of vestibular stimuli. (2) Body Representation: Numerous studies demonstrate that vestibular stimulation changes the representation of body parts, and sensitivity to tactile input or pain. Thus, the vestibular system plays an integral role in multisensory coordination of body representation. (3) Affective Processes and Disorders: Studies in psychiatric patients and patients with a vestibular disorder report a high comorbidity of vestibular dysfunctions and psychiatric symptoms. Recent studies investigated the beneficial effect of vestibular stimulation on psychiatric disorders, and how vestibular input can change mood and affect. These three emerging streams of research in vestibular science are-at least in part-associated with different neuronal core mechanisms. Spatial transformations draw on parietal areas, body representation is associated with somatosensory areas, and affective processes involve insular and cingulate cortices, all of which receive vestibular input. Even though a wide range of different vestibular cortical projection areas has been ascertained, their functionality still is scarcely understood.

  5. Spatial Cognition, Body Representation and Affective Processes: The Role of Vestibular Information beyond Ocular Reflexes and Control of Posture

    Directory of Open Access Journals (Sweden)

    Fred W Mast

    2014-05-01

    Full Text Available A growing number of studies in humans demonstrate the involvement of vestibular information in tasks that are seemingly remote from well-known functions such as space constancy or postural control. In this review article we point out three emerging streams of research highlighting the importance of vestibular input: 1 Spatial Cognition: Modulation of vestibular signals can induce specific changes in spatial cognitive tasks like mental imagery and the processing of numbers. This has been shown in studies manipulating body orientation (changing the input from the otoliths, body rotation (changing the input from the semicircular canals, in clinical findings with vestibular patients, and in studies carried out in microgravity. There is also an effect in the reverse direction; top-down processes can affect perception of vestibular stimuli. 2 Body Representation: Numerous studies demonstrate that vestibular stimulation changes the representation of body parts, and sensitivity to tactile input or pain. Thus, the vestibular system plays an integral role in multisensory coordination of body representation. 3 Affective Processes and Disorders: Studies in psychiatric patients and patients with a vestibular disorder report a high comorbidity of vestibular dysfunctions and psychiatric symptoms. Recent studies investigated the beneficial effect of vestibular stimulation on psychiatric disorders, and how vestibular input can change mood and affect. These three emerging streams of research in vestibular science are – at least in part – associated with different neuronal core mechanisms. Spatial transformations draw on parietal areas, body representation is associated with somatosensory areas, and affective processes involve insular and cingulate cortices, all of which receive vestibular input. Even though a wide range of different vestibular cortical projection areas has been ascertained, their functionality still is scarcely understood.

  6. Optimal control

    CERN Document Server

    Aschepkov, Leonid T; Kim, Taekyun; Agarwal, Ravi P

    2016-01-01

    This book is based on lectures from a one-year course at the Far Eastern Federal University (Vladivostok, Russia) as well as on workshops on optimal control offered to students at various mathematical departments at the university level. The main themes of the theory of linear and nonlinear systems are considered, including the basic problem of establishing the necessary and sufficient conditions of optimal processes. In the first part of the course, the theory of linear control systems is constructed on the basis of the separation theorem and the concept of a reachability set. The authors prove the closure of a reachability set in the class of piecewise continuous controls, and the problems of controllability, observability, identification, performance and terminal control are also considered. The second part of the course is devoted to nonlinear control systems. Using the method of variations and the Lagrange multipliers rule of nonlinear problems, the authors prove the Pontryagin maximum principle for prob...

  7. CONTROL ORGANIZACIONAL

    OpenAIRE

    Granda Carazas, Segundo Eloy; Facultad de Ciencias Contables, Universidad Nacional Mayor de San Marcos

    2014-01-01

    El concepto de control puede ser muy general y empleársele como punto focal para el sistema administrativo. Por ejemplo la planeación puede ser imaginada como medio para lograr el control del comportamiento individual u organizacional. En forma similar, la tarea de organización puede ser construida de manera que proporcione un medio para el control de las actividades.

  8. Birth Control

    Science.gov (United States)

    ... to have sex makes sense Talking to your parents about sex Deciding about sex Birth control Types of birth ... not planned. Some young people are afraid their parents will find out they’re having sex. If you get birth control from a doctor, ...

  9. Experiencing control

    NARCIS (Netherlands)

    Monaci, G.; Braspenning, R.A.C.; Meerbeek, B.W.; Bingley, P.; Rajagopalan, R.; Triki, M.

    2009-01-01

    This report describes the activities carried out in the first part of the Experiencing Control project (2008-324). The guiding idea of the project is to make control part of the experience, exploring new interaction solutions for complex, engaging interactions with Philips devices in the living

  10. Taking Control

    Centers for Disease Control (CDC) Podcasts

    2007-11-01

    This podcast gives action steps and reasons to control diabetes.  Created: 11/1/2007 by National Diabetes Education Program (NDEP), a joint program of the Centers for Disease Control and Prevention and the National Institutes of Health.   Date Released: 11/2/2007.

  11. Detonation control

    Science.gov (United States)

    Mace, Jonathan L.; Seitz, Gerald J.; Bronisz, Lawrence E.

    2016-10-25

    Detonation control modules and detonation control circuits are provided herein. A trigger input signal can cause a detonation control module to trigger a detonator. A detonation control module can include a timing circuit, a light-producing diode such as a laser diode, an optically triggered diode, and a high-voltage capacitor. The trigger input signal can activate the timing circuit. The timing circuit can control activation of the light-producing diode. Activation of the light-producing diode illuminates and activates the optically triggered diode. The optically triggered diode can be coupled between the high-voltage capacitor and the detonator. Activation of the optically triggered diode causes a power pulse to be released from the high-voltage capacitor that triggers the detonator.

  12. Control theory

    CERN Document Server

    Simrock, S

    2008-01-01

    In engineering and mathematics, control theory deals with the behaviour of dynamical systems. The desired output of a system is called the reference. When one or more output variables of a system need to follow a certain reference over time, a controller manipulates the inputs to a system to obtain the desired effect on the output of the system. Rapid advances in digital system technology have radically altered the control design options. It has become routinely practicable to design very complicated digital controllers and to carry out the extensive calculations required for their design. These advances in implementation and design capability can be obtained at low cost because of the widespread availability of inexpensive and powerful digital processing platforms and high-speed analog IO devices.

  13. Institutional Controls

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset consists of institutional control data from multiple Superfund sites in U.S. EPA Region 8. These data were acquired from multiple sources at different...

  14. Losing control

    DEFF Research Database (Denmark)

    Leppink, Eric; Odlaug, Brian Lawrence; Lust, Katherine

    2014-01-01

    OBJECTIVE: Assaultive behaviors are common among young people and have been associated with a range of other unhealthy, impulsive behaviors such as substance use and problem gambling. This study sought to determine the predictive ability of single assaultive incidents for impulse control disorders...... with respondents without lifetime assaultive behavior, those with a history of assaultive or destructive behavior reported more depressive symptoms, more stress, and higher rates of a range of impulse control disorders (intermittent explosive disorder, compulsive sexual behavior, compulsive buying, and skin...... picking disorder). CONCLUSIONS: Assaultive behavior appears fairly common among college students and is associated with symptoms of depression and impulse control disorders. Significant distress and diminished behavioral control suggest that assaultive behaviors may often be associated with significant...

  15. CYCLE CONTROL

    African Journals Online (AJOL)

    changed to gestodene. Although large- scale comparative trials are needed to confirm this finding, evidence suggests that cycle control with gestodene is better than for monophasic preparations containing desogestrel, norgestimate or levonorgestrel,10 as well as for levonorg- estrel-or norethisterone-containing triphasics.

  16. Associational control

    DEFF Research Database (Denmark)

    Hvid, Helge Søndergaard; Lund, Henrik Lambrecht; Grosen, Sidsel Lond

    2010-01-01

    significance in the modern workplace which is simultaneously characterized by self-management and standardization. It is concluded that the concept of control remains important, but needs to evolve from its focus on the work of individuals to a focus on the associational aspects of work if it is to retain its...

  17. Control Cognitivo

    Directory of Open Access Journals (Sweden)

    María Pavón

    2013-12-01

    Full Text Available Las respuestas obtenidas permitieron dilucidar tanto las diversas situaciones en que las personas intentan controlar cognitivamente sus emociones, así como las estrategias que utilizan para lograr dicho fin. A partir de un análisis de contenido centrado en las respuestas, surgieron dos sistemas clasificatorios: el primero hace referencia a los motivos que hacen que una persona controle cognitivamente sus emociones y contiene las siguientes dimensiones: según valencia de emoción, intensidad de la emoción, según tipo de relación, según situación o contexto y según grado de simetría. El segundo sistema clasificatorio mencionado, refiere a los mecanismos de control que las personas entrevistadas utilizan. Esta clasificación consta de 4 dimensiones: distracción, evitación reflexión y supresión emocional. Los resultados indican tanto similitudes como diferencias entre los grupos. Respecto a estas últimas, las más relevantes se encontraron entre el grupo de personas de 20 a 30 años y las de 80 a 90. Se ha encontrado que con el correr de los años, las personas empiezan a poner énfasis en el valor de la experiencia para afrontar y controlar las diferentes situaciones.

  18. COPD - control drugs

    Science.gov (United States)

    Chronic obstructive pulmonary disease - control drugs; Bronchodilators - COPD - control drugs; Beta agonist inhaler - COPD - control drugs; Anticholinergic inhaler - COPD - control drugs; Long-acting inhaler - COPD - control drugs; Corticosteroid inhaler - COPD - control ...

  19. Control Prenatal

    Directory of Open Access Journals (Sweden)

    P. Susana Aguilera, DRA.

    2014-11-01

    Full Text Available Los principales objetivos del control prenatal son identificar aquellos pacientes de mayor riesgo, con el fin de realizar intervenciones en forma oportuna que permitan prevenir dichos riesgos y así lograr un buen resultado perinatal. Esto se realiza a través de la historia médica y reproductiva de la mujer, el examen físico, la realización de algunos exámenes de laboratorio y exámenes de ultrasonido. Además es importante promover estilos de vida saludables, la suplementación de ácido fólico, una consejería nutricional y educación al respecto.

  20. Custom controls

    Science.gov (United States)

    Butell, Bart

    1996-02-01

    Microsoft's Visual Basic (VB) and Borland's Delphi provide an extremely robust programming environment for delivering multimedia solutions for interactive kiosks, games and titles. Their object oriented use of standard and custom controls enable a user to build extremely powerful applications. A multipurpose, database enabled programming environment that can provide an event driven interface functions as a multimedia kernel. This kernel can provide a variety of authoring solutions (e.g. a timeline based model similar to Macromedia Director or a node authoring model similar to Icon Author). At the heart of the kernel is a set of low level multimedia components providing object oriented interfaces for graphics, audio, video and imaging. Data preparation tools (e.g., layout, palette and Sprite Editors) could be built to manage the media database. The flexible interface for VB allows the construction of an infinite number of user models. The proliferation of these models within a popular, easy to use environment will allow the vast developer segment of 'producer' types to bring their ideas to the market. This is the key to building exciting, content rich multimedia solutions. Microsoft's VB and Borland's Delphi environments combined with multimedia components enable these possibilities.

  1. Formation of otoconia in the Japanese red-bellied newt, Cynops pyrrhogaster

    Science.gov (United States)

    Wiederhold, M. L.; Yamashita, M.; Larsen, K.; Asashima, M.

    1994-08-01

    Pre-mated adult female newts and fertilized eggs will be flown on the International Microgravity Laboratory-2 flight, in 1994. One objective of the flight will be to observe the influence of microgravity on the development of the gravity-sensing organs in the inner ear. These organs contain sensory hair cells covered by a layer of dense stones (otoconia). Gravity and linear acceleration exert forces on these masses, leading to excitation of the nerve fibers innervating the hair cells. If the production of the otoliths is regulated to reach an optimal weight, their development might be abnormal in microgravity. Ground-based control experiments are reported describing the developmental sequence in which both the otoliths and their associated sensory epithelium and the semicircular canals appear and develop. Three-dimensional reconstruction of serial sections through the otic vesicle of newt embryos at stages 31 through 58 demonstrate the first appearance, relative position and growth of the otoliths. Reports of experiments in which fertilized frog eggs were flown on a Russian Cosmos mission conclude that the utricular otolith is increased in volume, whereas the saccular otolith maintains normal size, suggesting that at least in the utricle, the weight of the otolith might be regulated.

  2. Manual control in space research on perceptual-motor functions under zero gravity conditions (L-10)

    Science.gov (United States)

    Tada, Akira

    1993-01-01

    Are human abilities to control vehicles and other machines the same in space as those on Earth? The L-10 Manual Control Experiment of the First Materials Processing Tests (FMPT) started from this question. Suppose a pilot has the task to align the head of a space vehicle toward a target. His actions are to look at the target, to determine the vehicle movement, and to operate the manipulator. If the activity of the nervous system were the same as on Earth, the movements, of the eye and hand would become excessive because the muscles do not have to oppose gravity. The timing and amount of movement must be arranged for appropriate actions. The sensation of motion would also be affected by the loss of gravity because the mechanism of the otolith, the major acceleration sensor, depends on gravity. The possible instability of the sensation of direction may cause mistakes in the direction of control of manipulator movement. Thus, the experimental data can be used for designing man-machine systems in space, as well as for investigation of physiological mechanisms. In this experiment, the direction of vehicle heading is expressed by a light spot on an array of light emitting diodes and the manipulator is of a finger stick type. As the light spot moves up and down, the Japanese Payload Specialist, and the subject, must move the manipulator forward and backward to keep the movement of the light spot within the neighborhood of the central point of the display. The position of the light spot is computed in such a manner that when the stick is kept at the neutral position, a motion whose acceleration is proportional to the angle of deflection is added to the movement of the light spot. The Operator Describing Function, which is an expression of human control characteristics, can be calculated from 2 minutes of raw data of the light spot position and stick deflection. The 2 minutes of operation is called a run, and 8 runs with resting periods composes a session. The on

  3. Hierarchical Control of Thermostatically Controller Loads for Primary Frequency Control

    DEFF Research Database (Denmark)

    Zhao, Haoran; Wu, Qiuwei; Huang, Shaojun

    2016-01-01

    This paper proposes a hierarchical control of Thermostatically Controlled Loads (TCLs) to provide primary frequency control support. The control architecture is comprised of three levels. At the high level, an aggregator coordinates multiple distribution substations and dispatches the primary...... reserve references. At the middle level, distribution substations estimate the available power of TCLs based on the aggregated bin model, and dispatch control signals to individual TCLs. At the local level, a supplementary frequency control loop is implemented at the local controller, which makes TCLs...

  4. Adaptive Vehicle Traction Control

    OpenAIRE

    Lee, Hyeongcheol; Tomizuka, Masayoshi

    1995-01-01

    This report presents two different control algorithms for adaptive vehicle traction control, which includes wheel slip control, optimal time control, anti-spin acceleration and anti-skid control, and longitudinal platoon control. The two control algorithms are respectively based on adaptive fuzzy logic control and sliding mode control with on-line road condition estimation. Simulations of the two control methods are conducted using a complex nonlinear vehicle model as well as a simple linear ...

  5. From 'omics to otoliths: responses of an estuarine fish to endocrine disrupting compounds across biological scales.

    Directory of Open Access Journals (Sweden)

    Susanne M Brander

    Full Text Available Endocrine disrupting chemicals (EDCs cause physiological abnormalities and population decline in fishes. However, few studies have linked environmental EDC exposures with responses at multiple tiers of the biological hierarchy, including population-level effects. To this end, we undertook a four-tiered investigation in the impacted San Francisco Bay estuary with the Mississippi silverside (Menidia audens, a small pelagic fish. This approach demonstrated links between different EDC sources and fish responses at different levels of biological organization. First we determined that water from a study site primarily impacted by ranch run-off had only estrogenic activity in vitro, while water sampled from a site receiving a combination of urban, limited ranch run-off, and treated wastewater effluent had both estrogenic and androgenic activity. Secondly, at the molecular level we found that fish had higher mRNA levels for estrogen-responsive genes at the site where only estrogenic activity was detected but relatively lower expression levels where both estrogenic and androgenic EDCs were detected. Thirdly, at the organism level, males at the site exposed to both estrogens and androgens had significantly lower mean gonadal somatic indices, significantly higher incidence of severe testicular necrosis and altered somatic growth relative to the site where only estrogens were detected. Finally, at the population level, the sex ratio was significantly skewed towards males at the site with measured androgenic and estrogenic activity. Our results suggest that mixtures of androgenic and estrogenic EDCs have antagonistic and potentially additive effects depending on the biological scale being assessed, and that mixtures containing androgens and estrogens may produce unexpected effects. In summary, evaluating EDC response at multiple tiers is necessary to determine the source of disruption (lowest scale, i.e. cell line and what the ecological impact will be (largest scale, i.e. sex ratio.

  6. Otolith shape as a valuable tool to evaluate the stock structure of ...

    African Journals Online (AJOL)

    Furthermore, linear discriminant analysis (LDA) was performed and overall jackknife classification success reached 30%. Finally, a cluster analysis was conducted using Ward's hierarchical algorithm, which discriminated three different groups. However, each group consisted of individual samples from all geographical ...

  7. Migration of diadromous and landlocked smelt populations studies by otolith geochemistry

    NARCIS (Netherlands)

    Phung, A.T.; Tulp, I.Y.M.; Baeyens, W.; Elskens, M.; Leermakers, M.; Gao, Y.

    2015-01-01

    Laser ablation inductively coupled mass spectrometry (LA-ICPMS) was used to determine Sr and Ba profiles along the growth axis of otholiths of European smelt caught in the Wadden Sea, the IJsselmeer and the Markermeer and to investigate the migration behaviour of the fish between the freshwater

  8. Development of Vestibular Stochastic Resonance as a Sensorimotor Countermeasure: Improving Otolith Ocular and Motor Task Responses

    Science.gov (United States)

    Mulavara, Ajitkumar; Fiedler, Matthew; DeDios,Yiri E.; Galvan, Raquel; Bloomberg, Jacob; Wood, Scott

    2011-01-01

    Astronauts experience disturbances in sensorimotor function after spaceflight during the initial introduction to a gravitational environment, especially after long-duration missions. Stochastic resonance (SR) is a mechanism by which noise can assist and enhance the response of neural systems to relevant, imperceptible sensory signals. We have previously shown that imperceptible electrical stimulation of the vestibular system enhances balance performance while standing on an unstable surface. The goal of our present study is to develop a countermeasure based on vestibular SR that could improve central interpretation of vestibular input and improve motor task responses to mitigate associated risks.

  9. A bioenergetic approach to model and reconstruct individual life traits from fish otoliths

    DEFF Research Database (Denmark)

    Fablet, Ronan; Pecquerie, Laure; Høie, Hans

    2012-01-01

    for ecosystem and fisheries monitoring. They often lack validation, however, and the poor understanding of biomineralization mechanisms has led to striking examples of misinterpretations and subsequent erroneous conclusions in fish ecology and fisheries management. From the characterization of the physico...

  10. AFSC/ABL: Young of the year sablefish (Anoplopoma fimbria) voucher otoliths 1995-2004.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — We studied young of the year sablefish Anoplopoma fimbria to collect basic life history information on their abundance, growth, and diet and to determine whether...

  11. Otoliths analysis of Mugil curema (Pisces: Mugilidae in Cuyutlan Lagoon, Mexico

    Directory of Open Access Journals (Sweden)

    E. Espino-Barr

    2013-01-01

    Full Text Available Se analizaron la morfología, la morfometría y los anillos de crecimiento de los otolitos: sagitta, asteriscus y lapillus de la lebrancha o liseta Mugil curema de la Laguna de Cuyutlán, Colima, México; asimismo, se analizaron las diferencias entre derecho e izquierdo y entre sexos. Los ejemplares fueron obtenidos de la captura comercial en los meses de agosto a octubre de 2007, agosto de 2008 y julio de 2011. En todos los casos se observó que el crecimiento de los otolitos es excéntrico con respecto al núcleo. Las relaciones entre la longitud total del pez y la longitud y ancho de los otolitos demostraron que esta estructura puede usarse para describir el crecimiento del pez. Se identificaron seis anillos de crecimiento en las sagittae y asterisci: especímenes con dos anillos midieron 21.80 cm de longitud total (TL (± 1.41 desviación estándar, los de tres anillos 22.90 (± 0.91, con cuatro anillos midieron 25.30 (± 0.39, con cinco anillos 28.30 (± 0.78 y con seis anillos 31.10 cm (± 2.22. En los lapilli, debido a su gran grosor, no fue posible observar marcas de crecimiento. Durante la etapa inmadura, los otolitos de las hembras son de mayor tamaño, pero una vez que alcanzan la madurez sexual, los otolitos de los machos alcanzan longitudes mayores.

  12. Otoliths of the wolf-fishes (genus Anarrhichas Linnaeus, 1758) from the Northern Atlantic (Pisces, Perciformes)

    NARCIS (Netherlands)

    Nijssen, H.

    1964-01-01

    While working at the Rijksinstituut voor Visserijonderzoek (R.V.I.O.) at IJmuiden, I received through the courtesy of Mr. C. van Delft some specimens of the three northern Atlantic species of wolf-fishes. At IJmuiden they are brought in by commercial trawlers. The only data in the literature known

  13. Age, growth and distribution of the Antarctic fish Chaenocephalus aceratus based on otoliths

    Directory of Open Access Journals (Sweden)

    Ryszard Jacek Traczyk

    2015-10-01

    Żabrowski, M. 2000. The osteology and ossification variability of the skull of antarctic white-blooded fish Chaenodraco wilsoni Regan, 1914 (Channichthyidae, Notothenioidei. W-wa : Acta Icht. Piscat. 30 (2: 111-126.

  14. Migratory Patterns of American Shad (Alosa Sapidissima) Revealed by Natural Geochemical Tags in Otoliths

    Science.gov (United States)

    2007-02-01

    Institute of Marine Research, Arendal, Norway . pp. 591-608. 193 Gunther, D., & Heinrich, C.A. 1999. Enhanced sensitivity in laser ablation-ICP mass... deuterium in river waters across the United States. Hydrological Processes 15: 1363-1393. Kennedy, B.P., Folt, C.L., Blum, J.D., & Chamberlain, C.P

  15. Controlling Separation in Turbomachines

    Science.gov (United States)

    Evans, Simon; Himmel, Christoph; Power, Bronwyn; Wakelam, Christian; Xu, Liping; Hynes, Tom; Hodson, Howard

    2010-01-01

    Four examples of flow control: 1) Passive control of LP turbine blades (Laminar separation control). 2) Aspiration of a conventional axial compressor blade (Turbulent separation control). 3) Compressor blade designed for aspiration (Turbulent separation control). 4.Control of intakes in crosswinds (Turbulent separation control).

  16. Contact Control, Version 1

    Energy Technology Data Exchange (ETDEWEB)

    2016-07-21

    The contact control code is a generalized force control scheme meant to interface with a robotic arm being controlled using the Robot Operating System (ROS). The code allows the user to specify a control scheme for each control dimension in a way that many different control task controllers could be built from the same generalized controller. The input to the code includes maximum velocity, maximum force, maximum displacement, and a control law assigned to each direction and the output is a 6 degree of freedom velocity command that is sent to the robot controller.

  17. Quantum feedback control and classical control theory

    OpenAIRE

    Doherty, Andrew C.; Habib, Salman; Jacobs, Kurt; Mabuchi, Hideo; Tan, Sze M.

    2000-01-01

    We introduce and discuss the problem of quantum feedback control in the context of established formulations of classical control theory, examining conceptual analogies and essential differences. We describe the application of state-observer based control laws, familiar in classical control theory, to quantum systems and apply our methods to the particular case of switching the state of a particle in a double-well potential.

  18. Who's your momma? Recognizing maternal origin of juvenile steelhead using injections of strontium chloride to create transgenerational marks

    Science.gov (United States)

    Shippentower, Gene E.; Schreck, Carl B.; Heppell, Scott A.

    2011-01-01

    We sought to determine whether a strontium chloride injection could be used to create a transgenerational otolith mark in steelhead Oncorhynchus mykiss. Two strontium injection trials and a survey of strontium: calcium (Sr:Ca) ratios in juvenile steelhead from various steelhead hatcheries were conducted to test the feasibility of the technique. In both trials, progeny of fish injected with strontium had significantly higher Sr:Ca ratios in the primordial region of their otoliths, as measured by an electron wavelength dispersive microprobe. In trial 1, the 5,000-mg/L treatment level showed that 56.8% of the otoliths were correctly classified, 12.2% being misclassified as belonging to the 0-mg/L treatment. In trial 2, the 20,000-mg/L treatment level showed that 30.8% of the otoliths were correctly classified, 13.5% being misclassified as belonging to the 0-mg/L treatment. There were no differences in the fertilization rates of eggs or survival rates of fry between the treatment and control groups. The Sr:Ca ratios in otoliths collected from various hatchery populations of steelhead varied and were greater than those found in otoliths from control fish in both of our injection trials. This study suggests that the marking technique led to recognizable increases in Sr:Ca ratios in some otoliths collected from fry produced by injected females. Not all progeny showed such increases, however, suggesting that the method holds promise but requires further refinement to reduce variation. Overall, there was a correct classification of about 40% across all treatments and trials; the variation in Sr:Ca ratios found among experimental trials and hatcheries indicates that care must be taken if the technique is employed where fish from more than one hatchery could be involved.

  19. PID control with robust disturbance feedback control

    DEFF Research Database (Denmark)

    Kawai, Fukiko; Vinther, Kasper; Andersen, Palle

    2015-01-01

    Disturbance Feedback Control (DFC) is a technique, originally proposed by Fuji Electric, for augmenting existing control systems with an extra feedback for attenuation of disturbances and model errors. In this work, we analyze the robustness and performance of a PID-based control system with DFC...... and performance (if such gains exist). Finally, two different simulation case studies are evaluated and compared. Our numerical studies indicate that better performance can be achieved with the proposed method compared with a conservatively tuned PID controller and comparable performance can be achieved when...... compared with an H-infinity controller....

  20. Adaptive Extremum Control and Wind Turbine Control

    DEFF Research Database (Denmark)

    Ma, Xin

    1997-01-01

    This thesis is divided into two parts, i.e., adaptive extremum control and modelling and control of a wind turbine. The rst part of the thesis deals with the design of adaptive extremum controllers for some processes which have the behaviour that process should have as high e ciency as possible...... in parameters, and thus directly lends itself to parameter estimation and adaptive control. The extremum control law is derived based on static optimization of a performance function. For a process with nonlinearity at output the intermediate signal between the linear part and nonlinear part plays an important...... role. If it can be emphasis on control design. The models have beenvalidated by experimental data obtained from an existing wind turbine. The e ective wind speed experienced by the rotor of a wind turbine, which is often required by some control methods, is estimated by using a wind turbine as a wind...

  1. Motion control report

    CERN Document Server

    2013-01-01

    Please note this is a short discount publication. In today's manufacturing environment, Motion Control plays a major role in virtually every project.The Motion Control Report provides a comprehensive overview of the technology of Motion Control:* Design Considerations* Technologies* Methods to Control Motion* Examples of Motion Control in Systems* A Detailed Vendors List

  2. PID controllers' fragility.

    Science.gov (United States)

    Alfaro, Víctor M

    2007-10-01

    In this paper, an index for measuring fragility of proportional integral derivative (PID) controllers is proposed. This index relates the losses of robustness of the control loop when controller parameters change, to the nominal robustness of the control loop. Furthermore, it defines when a PID controller is fragile, nonfragile or resilient.

  3. Control Measure Dataset

    Data.gov (United States)

    U.S. Environmental Protection Agency — The EPA Control Measure Dataset is a collection of documents describing air pollution control available to regulated facilities for the control and abatement of air...

  4. Gross motor control

    Science.gov (United States)

    Gross motor control is the ability to make large, general movements (such as waving an arm or lifting a ... Gross motor control is a milestone in the development of an infant. Infants develop gross motor control before they ...

  5. Riot Control Agents

    Science.gov (United States)

    ... Submit What's this? Submit Button Facts About Riot Control Agents Interim document Recommend on Facebook Tweet Share Compartir FACT SHEET What riot control agents are Riot control agents (sometimes referred to ...

  6. Essure Permanent Birth Control

    Science.gov (United States)

    ... Prosthetics Essure Permanent Birth Control Essure Permanent Birth Control Share Tweet Linkedin Pin it More sharing options ... Print Essure is a a permanently implanted birth control device for women (female sterilization). Implantation of Essure ...

  7. Birth control pills - combination

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/patientinstructions/000655.htm Birth control pills - combination To use the sharing features on ... both progestin and estrogen. What Are Combination Birth Control Pills? Birth control pills help keep you from ...

  8. Birth Control Explorer

    Science.gov (United States)

    ... STIs Media Facebook Twitter Tumblr Shares · 579 Birth Control Explorer Sort by all methods most effective methods ... You are here Home » Birth Control Explorer Birth Control Explorer If you’re having sex —or if ...

  9. Wisdom Appliance Control System

    Science.gov (United States)

    Hendrick; Jheng, Jyun-Teng; Tsai, Chen-Chai; Liou, Jia-Wei; Wang, Zhi-Hao; Jong, Gwo-Jia

    2017-07-01

    Intelligent appliances wisdom involves security, home care, convenient and energy saving, but the home automation system is still one of the core unit, and also using micro-processing electronics technology to centralized and control the home electrical products and systems, such as: lighting, television, fan, air conditioning, stereo, it composed of front-controller systems and back-controller panels, user using front-controller to control command, and then through the back-controller to powered the device.

  10. Test Control Center (TCC)

    Data.gov (United States)

    Federal Laboratory Consortium — The Test Control Center (TCC) provides a consolidated facility for planning, coordinating, controlling, monitoring, and analyzing distributed test events. ,The TCC...

  11. Fuzzy controller adaptation

    Science.gov (United States)

    Myravyova, E. A.; Sharipov, M. I.; Radakina, D. S.

    2017-10-01

    During writing this work, the fuzzy controller with a double base of rules was studied, which was applied for the synthesis of the automated control system. A method for fuzzy controller adaptation has been developed. The adaptation allows the fuzzy controller to automatically compensate for parametric interferences that occur at the control object. Specifically, the fuzzy controller controlled the outlet steam temperature in the boiler unit BKZ-75-39 GMA. The software code was written in the programming support environment Unity Pro XL designed for fuzzy controller adaptation.

  12. Dynamic power flow controllers

    Science.gov (United States)

    Divan, Deepakraj M.; Prasai, Anish

    2017-03-07

    Dynamic power flow controllers are provided. A dynamic power flow controller may comprise a transformer and a power converter. The power converter is subject to low voltage stresses and not floated at line voltage. In addition, the power converter is rated at a fraction of the total power controlled. A dynamic power flow controller controls both the real and the reactive power flow between two AC sources having the same frequency. A dynamic power flow controller inserts a voltage with controllable magnitude and phase between two AC sources; thereby effecting control of active and reactive power flows between two AC sources.

  13. Robust control charts in statistical process control

    OpenAIRE

    Nazir, H.Z.

    2014-01-01

    The presence of outliers and contaminations in the output of the process highly affects the performance of the design structures of commonly used control charts and hence makes them of less practical use. One of the solutions to deal with this problem is to use control charts which are robust against violations of the basic assumptions, like normality. The effect of using robust or other alternative estimators has not been investigated thoroughly in perspective of control charting literature....

  14. Space Digital Controller for Improved Motor Control

    Science.gov (United States)

    Alves-Nunes, Samuel; Daras, Gaetan; Dehez, Bruno; Maillard, Christophe; Bekemans, Marc; Michel, Raymond

    2014-08-01

    Performing digital motor control into space equipment is a new challenge. The new DPC (Digital Programmable Controller) is the first chip that we can use as a micro-controller, allowing us to drive motors with digital control schemes. In this paper, the digital control of hybrid stepper motors is considered. This kind of motor is used for solar array rotation and antenna actuation. New digital control technology brings a lot of advantages, allowing an important reduction of thermal losses inside the motor, and a reduction of thermal constraints on power drive electronic components. The opportunity to drive motors with a digital controller also brings many new functionalities like post-failure torque analysis, micro- vibrations and cogging torque reduction, or electro- mechanical damping of solar array oscillations. To evaluate the performance of the system, Field-Oriented Control (FOC) is implemented on a hybrid stepper motor. A test-bench, made of an active load, has been made to emulate the mechanical behaviour of the solar array, by the use of a torsionally-compliant model. The experimental results show that we can drastically reduce electrical power consumption, compared with the currently used open-loop control scheme.

  15. Control and optimal control theories with applications

    CERN Document Server

    Burghes, D N

    2004-01-01

    This sound introduction to classical and modern control theory concentrates on fundamental concepts. Employing the minimum of mathematical elaboration, it investigates the many applications of control theory to varied and important present-day problems, e.g. economic growth, resource depletion, disease epidemics, exploited population, and rocket trajectories. An original feature is the amount of space devoted to the important and fascinating subject of optimal control. The work is divided into two parts. Part one deals with the control of linear time-continuous systems, using both transfer fun

  16. Improving Control of Two Motor Controllers

    Science.gov (United States)

    Toland, Ronald W.

    2004-01-01

    A computer program controls motors that drive translation stages in a metrology system that consists of a pair of two-axis cathetometers. This program is specific to Compumotor Gemini (or equivalent) motors and the Compumotor 6K-series (or equivalent) motor controller. Relative to the software supplied with the controller, this program affords more capabilities and is easier to use. Written as a Virtual Instrument in the LabVIEW software system, the program presents an imitation control panel that the user can manipulate by use of a keyboard and mouse. There are three modes of operation: command, movement, and joystick. In command mode, single commands are sent to the controller for troubleshooting. In movement mode, distance, speed, and/or acceleration commands are sent to the controller. Position readouts from the motors and from position encoders on the translation stages are displayed in marked fields. At any time, the position readouts can be recorded in a file named by the user. In joystick mode, the program yields control of the motors to a joystick. The program sends commands to, and receives data from, the controller via a serial cable connection, using the serial-communication portion of the software supplied with the controller.

  17. Robust control charts in statistical process control

    NARCIS (Netherlands)

    Nazir, H.Z.

    2014-01-01

    The presence of outliers and contaminations in the output of the process highly affects the performance of the design structures of commonly used control charts and hence makes them of less practical use. One of the solutions to deal with this problem is to use control charts which are robust

  18. Control of Bioprocesses

    DEFF Research Database (Denmark)

    Huusom, Jakob Kjøbsted

    2015-01-01

    industries. It also provides a number of typical control loops for different objectives. A brief introduction to the general principles of process control, the PID control algorithm is discussed, and the design and effect of tuning are shown in an example. Finally, a discussion of novel, model-free control...

  19. Aircraft adaptive learning control

    Science.gov (United States)

    Lee, P. S. T.; Vanlandingham, H. F.

    1979-01-01

    The optimal control theory of stochastic linear systems is discussed in terms of the advantages of distributed-control systems, and the control of randomly-sampled systems. An optimal solution to longitudinal control is derived and applied to the F-8 DFBW aircraft. A randomly-sampled linear process model with additive process and noise is developed.

  20. Applied predictive control

    CERN Document Server

    Sunan, Huang; Heng, Lee Tong

    2002-01-01

    The presence of considerable time delays in the dynamics of many industrial processes, leading to difficult problems in the associated closed-loop control systems, is a well-recognized phenomenon. The performance achievable in conventional feedback control systems can be significantly degraded if an industrial process has a relatively large time delay compared with the dominant time constant. Under these circumstances, advanced predictive control is necessary to improve the performance of the control system significantly. The book is a focused treatment of the subject matter, including the fundamentals and some state-of-the-art developments in the field of predictive control. Three main schemes for advanced predictive control are addressed in this book: • Smith Predictive Control; • Generalised Predictive Control; • a form of predictive control based on Finite Spectrum Assignment. A substantial part of the book addresses application issues in predictive control, providing several interesting case studie...

  1. Foundations Of Fuzzy Control

    DEFF Research Database (Denmark)

    Jantzen, Jan

    The objective of this textbook is to acquire an understanding of the behaviour of fuzzy logic controllers. Under certain conditions a fuzzy controller is equivalent to a proportional-integral-derivative (PID) controller. Using that equivalence as a link, the book applies analysis methods from...... linear and nonlinear control theory. In the linear domain, PID tuning methods and stability analyses are transferred to linear fuzzy controllers. The Nyquist plot shows the robustness of different settings of the fuzzy gain parameters. As a result, a fuzzy controller is guaranteed to perform as well...... as any PID controller. In the nonlinear domain, the stability of four standard control surfaces is analysed by means of describing functions and Nyquist plots. The self-organizing controller (SOC) is shown to be a model reference adaptive controller. There is a possibility that a nonlinear fuzzy PID...

  2. Self adapting control charts

    OpenAIRE

    Albers, Willem/Wim; Kallenberg, W. C. M.

    2004-01-01

    When the distributional form of the observations differs from normality, standard control charts are often seriously in error. Such model errors can be avoided with (modified) nonparametric control charts. Unfortunately, these control charts suffer from large stochastic errors due to estimation. In between are so called parametric control charts. All three of them are discussed in this paper as well as a combined chart, which chooses one of the three control charts according to the appropriat...

  3. Robo-Wrist Controller

    OpenAIRE

    Faraquddin Ahamed, Mohamed Athiq

    2015-01-01

    Robo-wrist controller is a Graphical User Interface (GUI) based application designed and developed to control, and monitor a wrist exoskeleton driven by micro-controllers. The software application is developed to better assist a physiotherapist in administering physical therapy to stroke patients with the help of the exoskeleton. Since the micro-controller device that directly controls the exoskeleton is not very intuitive to use and lacks visual feedback, a software application fills these g...

  4. Controller Architectures for Switching

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Poulsen, Niels Kjølstad

    2009-01-01

    This paper investigate different controller architectures in connection with controller switching. The controller switching is derived by using the Youla-Jabr-Bongiorno-Kucera (YJBK) parameterization. A number of different architectures for the implementation of the YJBK parameterization...... are described and applied in connection with controller switching. An architecture that does not include inversion of the coprime factors is introduced. This architecture will make controller switching particular simple....

  5. Fuzzy and neural control

    Science.gov (United States)

    Berenji, Hamid R.

    1992-01-01

    Fuzzy logic and neural networks provide new methods for designing control systems. Fuzzy logic controllers do not require a complete analytical model of a dynamic system and can provide knowledge-based heuristic controllers for ill-defined and complex systems. Neural networks can be used for learning control. In this chapter, we discuss hybrid methods using fuzzy logic and neural networks which can start with an approximate control knowledge base and refine it through reinforcement learning.

  6. Spatial orientation and balance control changes induced by altered gravitoinertial force vectors.

    Science.gov (United States)

    Kaufman, G D; Wood, S J; Gianna, C C; Black, F O; Paloski, W H

    2001-04-01

    were short-lived, however, with a recovery time of several postural test trials (minutes). There were also asymmetries in the direction of postcentrifugation COP and head tilt which depended on the subject's orientation during the centrifugation adaptation period (left ear or right ear out). The amount of total head movements during centrifugation correlated poorly or inversely with postcentrifugation postural stability, and the most unstable subject made no head movements. There was no decrease in postural stability after static tilt, although these subjects also reported a perceived tilt briefly after return to upright, and they also had COP asymmetries. Abnormal subjects underestimated roll-tilt during centrifugation, and their directed saccades revealed permanent spatial distortions. Bilateral abnormal subjects started out with poor postural control, but showed no postural decrements after centrifugation, while unilateral abnormal subjects had varying degrees of postural decrement, both in their everyday function and as a result of experiencing the centrifugation. In addition, three unilateral, abnormal subjects, who rode twice in opposite orientations, revealed a consistent orthogonal pattern of COP offsets after centrifugation. These results suggest that both orientation and magnitude of the gravitoinertial vector are used by the central nervous system for calibration of multiple orientation systems. A change in the background gravitoinertial force (otolith input) can rapidly initiate postural and perceptual adaptation in several sensorimotor systems, independent of a structured visual surround.

  7. Vehicle Dynamics and Control

    CERN Document Server

    Rajamani, Rajesh

    2012-01-01

    Vehicle Dynamics and Control provides a comprehensive coverage of vehicle control systems and the dynamic models used in the development of these control systems. The control system applications covered in the book include cruise control, adaptive cruise control, ABS, automated lane keeping, automated highway systems, yaw stability control, engine control, passive, active and semi-active suspensions, tire-road friction coefficient estimation, rollover prevention, and hybrid electric vehicle. In developing the dynamic model for each application, an effort is made to both keep the model simple enough for control system design but at the same time rich enough to capture the essential features of the dynamics. A special effort has been made to explain the several different tire models commonly used in literature and to interpret them physically. In the second edition of the book, chapters on roll dynamics, rollover prevention and hybrid electric vehicles have been added, and the chapter on electronic stability co...

  8. Switching Between Multivariable Controllers

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Stoustrup, Jakob; Abrahamsen, Rune

    2004-01-01

    it is possible to smoothly switch between multivariable controllers with guaranteed closed-loop stability. This includes also the case where one or more controllers are unstable. The concept for smooth online changes of multivariable controllers based on the YJBK architecture can also handle the start up......A concept for implementation of multivariable controllers is presented in this paper. The concept is based on the Youla-Jabr-Bongiorno-Kucera (YJBK) parameterization of all stabilizing controllers. By using this architecture for implementation of multivariable controllers, it is shown how...... and shut down of multivariable systems. Furthermore, the start up of unstable multivariable controllers can be handled as well. Finally, implementation of (unstable) controllers as a stable Q parameter in a Q-parameterized controller can also be achieved....

  9. Robot welding process control

    Science.gov (United States)

    Romine, Peter L.

    1991-01-01

    This final report documents the development and installation of software and hardware for Robotic Welding Process Control. Primary emphasis is on serial communications between the CYRO 750 robotic welder, Heurikon minicomputer running Hunter & Ready VRTX, and an IBM PC/AT, for offline programming and control and closed-loop welding control. The requirements for completion of the implementation of the Rocketdyne weld tracking control are discussed. The procedure for downloading programs from the Intergraph, over the network, is discussed. Conclusions are made on the results of this task, and recommendations are made for efficient implementation of communications, weld process control development, and advanced process control procedures using the Heurikon.

  10. Control system design method

    Science.gov (United States)

    Wilson, David G [Tijeras, NM; Robinett, III, Rush D.

    2012-02-21

    A control system design method and concomitant control system comprising representing a physical apparatus to be controlled as a Hamiltonian system, determining elements of the Hamiltonian system representation which are power generators, power dissipators, and power storage devices, analyzing stability and performance of the Hamiltonian system based on the results of the determining step and determining necessary and sufficient conditions for stability of the Hamiltonian system, creating a stable control system based on the results of the analyzing step, and employing the resulting control system to control the physical apparatus.

  11. Control integral systems; Sistemas integrales de control

    Energy Technology Data Exchange (ETDEWEB)

    Burgos, Estrella [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1998-12-31

    Almost two third of the electric power generation in Mexico are obtained from hydrocarbons, for that reasons Comision Federal de Electricidad (CFE) dedicated special commitment in modernizing the operation of fossil fuel central stations. In attaining this objective the control systems play a fundamental roll, from them depend a good share of the reliability and the efficiency of the electric power generation process, as well as the extension of the equipment useful life. Since 1984 the Instituto de Investigaciones Electricas (IIE) has been working, upon the request of CFE, on the development of digital control systems. To date it has designed and implemented a logic control system for gas burners, which controls 32 burners of the Unit 4 boiler of the Generation Central of Valle de Mexico and two systems for distributed control for two combined cycle central stations, which are: Dos Bocas, Veracruz Combined cycle central, and Gomez Palacio, Durango combined cycle central. With these two developments the IIE enters the World tendency of implementing distributed control systems for the fossil fuel power central update [Espanol] Casi las dos terceras partes de la generacion electrica en Mexico se obtienen a partir de hidrocarburos, es por eso que la Comision Federal de Electricidad (CFE) puso especial empeno en modernizar la operacion de las centrales termoelectricas de combustibles fosiles. En el logro de este objetivo los sistemas de control desempenan un papel fundamental, de ellos depende una buena parte la confiabilidad y la eficiencia en el proceso de generacion de energia electrica, asi como la prolongacion de la vida util de los equipos. Desde 1984 el Instituto de Investigaciones Electricas (IIE) ha trabajado, a solicitud de la CFE, en el desarrollo de sistemas digitales de control. A la fecha se han disenado e implantado un sistema de control logico de quemadores de gas, el cual controla 32 quemadores de la caldera de la unidad 4 de la central de generacion

  12. Reproduction of ON-center and OFF-center self-rotations.

    Science.gov (United States)

    Israël, I; Crockett, M; Zupan, L; Merfeld, D

    2005-06-01

    In self-rotation reproduction tasks, subjects appear to estimate the displacement angle and then reproduce this angle without necessarily replicating the entire temporal velocity profile. In contrast, subjects appear to reproduce the entire temporal velocity profile during linear motion stimulating the otoliths. To investigate what happens during combined rotation and translation, we investigated in darkness the central processing of vestibular cues during eccentric rotation. Controlling a centrifuge with a joystick, nine healthy subjects were asked to reproduce the angle of the previously imposed rotation. Rotations were either ON-center, or 50 cm OFF-center with inter-aural centripetal acceleration. Rotation duration was either variable (proportional to the traveled angle), or constant. We examined whether the stimulation of the otoliths during OFF-center rotation changes self-rotation reproduction, and whether rotation duration is processed differently by the nervous system with and without otolith stimulation. As postulated, the subjects indeed reproduced more closely the stimulus velocity profile when OFF-center. But the primary result is that the additional supra-threshold linear acceleration cues, measured by the otoliths, did not improve performance. More specifically, to our surprise, the ability to reproduce rotation angle degraded slightly in the presence of additional information from the otolith organs, with the linear acceleration cues appearing to interfere with the reproduction of movement duration.

  13. Detection of Helicobacter and Campylobacter spp. from the aquatic environment of marine mammals.

    Science.gov (United States)

    Goldman, C G; Matteo, M J; Loureiro, J D; Degrossi, J; Teves, S; Heredia, S Rodriguez; Alvarez, K; González, A Beltrán; Catalano, M; Boccio, J; Cremaschi, G; Solnick, J V; Zubillaga, M B

    2009-01-13

    The mechanism by which Helicobacter species are transmitted remains unclear. To examine the possible role of environmental transmission in marine mammals, we sought the presence of Helicobacter spp. and non-Helicobacter bacteria within the order Campylobacterales in water from the aquatic environment of marine mammals, and in fish otoliths regurgitated by dolphins. Water was collected from six pools, two inhabited by dolphins and four inhabited by seals. Regurgitated otoliths were collected from the bottom of dolphins' pools. Samples were evaluated by culture, PCR and DNA sequence analysis. Sequences from dolphins' water and from regurgitated otoliths clustered with 99.8-100% homology with sequences from gastric fluids, dental plaque and saliva from dolphins living in those pools, and with 99.5% homology with H. cetorum. Sequences from seals' water clustered with 99.5% homology with a sequence amplified from a Northern sea lion (AY203900). Control PCR on source water for the pools and from otoliths dissected from feeder fish were negative. The findings of Helicobacter spp. DNA in the aquatic environment suggests that contaminated water from regurgitated fish otoliths and perhaps other tissues may play a role in Helicobacter transmission among marine mammals.

  14. Switching Systems: Controllability and Control Design

    Science.gov (United States)

    2009-04-25

    TERMS EOARD, Navigation, Comunications & Guidance, Complex Systems 16. SECURITY CLASSIFICATION OF: 19a. NAME OF RESPONSIBLE PERSON JAMES LAWTON Ph...Switching Systems : Controllability and Control Design 5c. PROGRAM ELEMENT NUMBER 5d. PROJECT NUMBER 5d. TASK NUMBER 6. AUTHOR(S) Professor...ABSTRACT Motivated by the need of dealing with physical systems that exhibit a more complicated behavior than those normally described by

  15. Ontology Based Access Control

    Directory of Open Access Journals (Sweden)

    Özgü CAN

    2010-02-01

    Full Text Available As computer technologies become pervasive, the need for access control mechanisms grow. The purpose of an access control is to limit the operations that a computer system user can perform. Thus, access control ensures to prevent an activity which can lead to a security breach. For the success of Semantic Web, that allows machines to share and reuse the information by using formal semantics for machines to communicate with other machines, access control mechanisms are needed. Access control mechanism indicates certain constraints which must be achieved by the user before performing an operation to provide a secure Semantic Web. In this work, unlike traditional access control mechanisms, an "Ontology Based Access Control" mechanism has been developed by using Semantic Web based policies. In this mechanism, ontologies are used to model the access control knowledge and domain knowledge is used to create policy ontologies.

  16. Controls and Interfaces

    CERN Document Server

    King, Q

    2015-01-01

    Reliable powering of accelerator magnets requires reliable power converters and controls, able to meet the powering specifications in the long term. In this paper, some of the issues that will challenge a power converter controls engineer are discussed.

  17. Switching Between Multivariable Controllers

    DEFF Research Database (Denmark)

    Niemann, H.; Stoustrup, Jakob; Abrahamsen, R.B.

    2004-01-01

    A concept for implementation of multivariable controllers is presented in this paper. The concept is based on the Youla-Jabr-Bongiorno-Kucera (YJBK) parameterization of all stabilizing controllers. By using this architecture for implementation of multivariable controllers, it is shown how it is p...... it is possible to smoothly switch between multivariable controllers with guaranteed closed-loop stability. This includes also the case where one or more controllers are unstable. Udgivelsesdato: MAR-APR......A concept for implementation of multivariable controllers is presented in this paper. The concept is based on the Youla-Jabr-Bongiorno-Kucera (YJBK) parameterization of all stabilizing controllers. By using this architecture for implementation of multivariable controllers, it is shown how...

  18. Scabies: Prevention and Control

    Science.gov (United States)

    ... Diseases Laboratory Diagnostic Assistance [DPDx] Parasites Home Prevention & Control Recommend on Facebook Tweet Share Compartir When a ... avoid outbreaks. Institutional outbreaks can be difficult to control and require a rapid, aggressive, and sustained response. ...

  19. Poison Control Centers

    Science.gov (United States)

    ... 1222 immediately. Name State American Association of Poison Control Centers Address AAPCC Central Office NOT A POISON ... not for emergency use. Arkansas ASPCA Animal Poison Control Center Address 1717 S. Philo Road, Suite 36 Urbana, ...

  20. Tight Diabetes Control

    Science.gov (United States)

    ... A A A Listen En Español Tight Diabetes Control Managing blood glucose can prevent or slow the ... prevents or slows some complications. For the Diabetes Control and Complications Trial (DCCT), researchers followed 1,441 ...

  1. Birth control pill - slideshow

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/presentations/100108.htm Birth control pill - series—Normal female anatomy To use the ... produce a successful pregnancy. To prevent pregnancy, birth control pills affect how these organs normally function. Review ...

  2. TIPONLINE Control Table

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The tiponline application is quite complex.It contains code, control,use local lists and control data. Those whou care about the inter workings of the application...

  3. NGS Survey Control Map

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NGS Survey Control Map provides a map of the US which allows you to find and display geodetic survey control points stored in the database of the National...

  4. Robust Self Tuning Controllers

    DEFF Research Database (Denmark)

    Poulsen, Niels Kjølstad

    1985-01-01

    The present thesis concerns robustness properties of adaptive controllers. It is addressed to methods for robustifying self tuning controllers with respect to abrupt changes in the plant parameters. In the thesis an algorithm for estimating abruptly changing parameters is presented. The estimator...... has several operation modes and a detector for controlling the mode. A special self tuning controller has been developed to regulate plant with changing time delay....

  5. Power oscillation damping controller

    DEFF Research Database (Denmark)

    2012-01-01

    A power oscillation damping controller is provided for a power generation device such as a wind turbine device. The power oscillation damping controller receives an oscillation indicating signal indicative of a power oscillation in an electricity network and provides an oscillation damping control...... signal in response to the oscillation indicating signal, by processing the oscillation damping control signal in a signal processing chain. The signal processing chain includes a filter configured for passing only signals within a predetermined frequency range....

  6. Distributed Power Flow Controller

    OpenAIRE

    Yuan, Z

    2010-01-01

    In modern power systems, there is a great demand to control the power flow actively. Power flow controlling devices (PFCDs) are required for such purpose, because the power flow over the lines is the nature result of the impedance of each line. Due to the control capabilities of different types of PFCDs, the trend is that mechanical PFCDs are gradually being replaced by Power electronics (PE) PFCDs. Among all PE PFCDs, the Unified Power Flow Controller (UPFC) is the most versatile device. How...

  7. Adaptive, predictive controller for optimal process control

    Energy Technology Data Exchange (ETDEWEB)

    Brown, S.K.; Baum, C.C.; Bowling, P.S.; Buescher, K.L.; Hanagandi, V.M.; Hinde, R.F. Jr.; Jones, R.D.; Parkinson, W.J.

    1995-12-01

    One can derive a model for use in a Model Predictive Controller (MPC) from first principles or from experimental data. Until recently, both methods failed for all but the simplest processes. First principles are almost always incomplete and fitting to experimental data fails for dimensions greater than one as well as for non-linear cases. Several authors have suggested the use of a neural network to fit the experimental data to a multi-dimensional and/or non-linear model. Most networks, however, use simple sigmoid functions and backpropagation for fitting. Training of these networks generally requires large amounts of data and, consequently, very long training times. In 1993 we reported on the tuning and optimization of a negative ion source using a special neural network[2]. One of the properties of this network (CNLSnet), a modified radial basis function network, is that it is able to fit data with few basis functions. Another is that its training is linear resulting in guaranteed convergence and rapid training. We found the training to be rapid enough to support real-time control. This work has been extended to incorporate this network into an MPC using the model built by the network for predictive control. This controller has shown some remarkable capabilities in such non-linear applications as continuous stirred exothermic tank reactors and high-purity fractional distillation columns[3]. The controller is able not only to build an appropriate model from operating data but also to thin the network continuously so that the model adapts to changing plant conditions. The controller is discussed as well as its possible use in various of the difficult control problems that face this community.

  8. Cooperative Control Method of Active and Semiactive Control: New Framework for Vibration Control

    OpenAIRE

    Kazuhiko Hiramoto

    2014-01-01

    A new control design framework for vibration control, the cooperative control of active and semiactive control, is proposed in the paper. In the cooperative control, a structural system having both of an actuator and a semiactive control device, for example, MR damper and so forth, is defined as the control object. In the proposed control approach, the higher control performance is aimed by the cooperative control between the active control with the actuator and the semiactive control with th...

  9. Birth Control Patch

    Science.gov (United States)

    ... that use hormones, such as the birth control pill or birth control ring , a girl uses the birth control patch based on her monthly menstrual cycle. She puts on the patch on the first day of her menstrual cycle or the first Sunday after her menstrual cycle begins. She will change the ...

  10. SPS : the control system

    CERN Multimedia

    CERN Neyrac Films

    1975-01-01

    English version. Part of the series of films produced by CERN about the SPS. "More than 10.000 things to control, 7,00 things to measure and 30,000 ? to survey, distributed over more than 10 square km. That was the problem which faced the controls group." Comments: images of control room, computer screens, and computer centre rather dark

  11. Fuzzy Control Tutorial

    DEFF Research Database (Denmark)

    Dotoli, M.; Jantzen, Jan

    1999-01-01

    The tutorial concerns automatic control of an inverted pendulum, especially rule based control by means of fuzzy logic. A ball balancer, implemented in a software simulator in Matlab, is used as a practical case study. The objectives of the tutorial are to teach the basics of fuzzy control...

  12. Finite Control in Korean

    Science.gov (United States)

    Lee, Kum Young

    2009-01-01

    This thesis explores finite control in Korean. An overview of the previous studies of control shows that the mainstream literature on control has consistently argued that referential dependence between an overt matrix argument and an embedded null subject is characteristic of non-finite clauses which contain a PRO subject. Moreover, although some…

  13. Survivability via Control Objectives

    Energy Technology Data Exchange (ETDEWEB)

    CAMPBELL,PHILIP L.

    2000-08-11

    Control objectives open an additional front in the survivability battle. A given set of control objectives is valuable if it represents good practices, it is complete (it covers all the necessary areas), and it is auditable. CobiT and BS 7799 are two examples of control objective sets.

  14. Distributed Power Flow Controller

    NARCIS (Netherlands)

    Yuan, Z.

    2010-01-01

    In modern power systems, there is a great demand to control the power flow actively. Power flow controlling devices (PFCDs) are required for such purpose, because the power flow over the lines is the nature result of the impedance of each line. Due to the control capabilities of different types of

  15. Worldwide Report, Arms Control

    Science.gov (United States)

    1985-09-21

    Intersoft- ware, Logic Control Control y Aplicaciones , Dielsa, Eliop, EISA, Sainco CTNE, Fagor Electronica, Standard CTNE, Fagor Electronica, Piher...regulation systems Industrial turbine of advanced design Alfa Sewing Machines Control y Aplicaciones , Danobat, Etxe-Tar C02, CO and ultraviolet lasers

  16. Optimisation of load control

    Energy Technology Data Exchange (ETDEWEB)

    Koponen, P. [VTT Energy, Espoo (Finland)

    1998-08-01

    Electricity cannot be stored in large quantities. That is why the electricity supply and consumption are always almost equal in large power supply systems. If this balance were disturbed beyond stability, the system or a part of it would collapse until a new stable equilibrium is reached. The balance between supply and consumption is mainly maintained by controlling the power production, but also the electricity consumption or, in other words, the load is controlled. Controlling the load of the power supply system is important, if easily controllable power production capacity is limited. Temporary shortage of capacity causes high peaks in the energy price in the electricity market. Load control either reduces the electricity consumption during peak consumption and peak price or moves electricity consumption to some other time. The project Optimisation of Load Control is a part of the EDISON research program for distribution automation. The following areas were studied: Optimization of space heating and ventilation, when electricity price is time variable, load control model in power purchase optimization, optimization of direct load control sequences, interaction between load control optimization and power purchase optimization, literature on load control, optimization methods and field tests and response models of direct load control and the effects of the electricity market deregulation on load control. An overview of the main results is given in this chapter

  17. Global marketing control

    NARCIS (Netherlands)

    John Rance; Galina Zhiltsova

    2009-01-01

    The reasoning issue of this work is to research and define the efficient methods of global marketing control. The report is focused on the following aspects: the importance of the control systems in global marketing environment, the relationship between planning and controlling, types and the

  18. Birth Control Pill

    Science.gov (United States)

    ... Counselors Kidney Stones Brain and Nervous System Birth Control Pill KidsHealth > For Teens > Birth Control Pill Print A A A What's in this ... La píldora anticonceptiva What Is It? The birth control pill (also called "the Pill") is a daily ...

  19. Birth Control Shot

    Science.gov (United States)

    ... Counselors Kidney Stones Brain and Nervous System Birth Control Shot KidsHealth > For Teens > Birth Control Shot Print A A A What's in this ... La inyección anticonceptiva What Is It? The birth control shot is a long-acting form of progesterone, ...

  20. Feedback control of sound

    Science.gov (United States)

    Rafaely, Boaz

    This thesis is concerned with the development an application of feedback control techniques for active sound control. Both fixed and adaptive controllers are considered. The controller design problem for active sound control is formulated as a constrained optimisation problem with an H2 performance objective, of minimising the variance of the control error, and H2 and H∞ design constraints involving control power output, disturbance enhancement, and robust stability. An Internal Model Controller with an FIR control filter is assumed. Conventional H2 design methods for feedback controllers are studied first. Although such controllers can satisfy the design constraints by employing effort terms in the quadratic cost function, they do not achieve the best possible performance, and when adapted using LMS-based algorithms, they suffer from instabilities if the plant response varies significantly. Improved H2/H∞ design methods for fixed and adaptive controllers are then developed, which achieve the best H2 performance under the design constraints, offer an improved stability when made adaptive, and in general outperform the conventional H2 controllers. The H2/H∞ design problems employ convex programming to ensure a unique solution. The Sequential Quadratic Programming methods is used for the off-line design of fixed controllers, and penalty and barrier function methods, together with frequency domain LMS-based algorithms are employed in the H2/H∞ adaptive controllers. The controllers studied and developed here were applied to three active sound control systems: a noise-reducing headset, an active headrest, and a sound radiating panel. The emphasis was put on developing control strategies that improve system performance. First, a high performance controller for the noise-reducing headset was implemented in real-time, which combines analogue and adaptive digital controllers, and can thus reject disturbances which has both broad-band and periodic components. Then

  1. Control of wastewater using multivariate control chart

    Science.gov (United States)

    Nugraha, Jaka; Fatimah, Is; Prabowo, Rino Galang

    2017-03-01

    Wastewater treatment is a crucial process in industry cause untreated or improper treatment of wastewater may leads some problems affecting to the other parts of environmental aspects. For many kinds of wastewater treatments, the parameters of Biological Oxygen Demand (BOD), Chemical Oxygen Demand (COD), and the Total Suspend Solid (TSS) are usual parameters to be controlled as a standard. In this paper, the application of multivariate Hotteling T2 Individual was reported to control wastewater treatment. By using wastewater treatment data from PT. ICBP, east Java branch, while the fulfillment of quality standards are based on East Java Governor Regulation No. 72 Year 2013 on Standards of Quality of Waste Water Industry and / or Other Business Activities. The obtained results are COD and TSS has a correlation with BOD values with the correlation coefficient higher than 50%, and it is is also found that influence of the COD and TSS to BOD values are 82% and 1.9% respectively. Based on Multivariate control chart Individual T2 Hotteling, it is found that BOD-COD and BOD-TSS are each one subgroup that are outside the control limits. Thus, it can be said there is a process that is not multivariate controlled, but univariately the variables of BOD, COD and TSS are within specification (standard quality) that has been determined.

  2. Control and optimization system

    Science.gov (United States)

    Xinsheng, Lou

    2013-02-12

    A system for optimizing a power plant includes a chemical loop having an input for receiving an input parameter (270) and an output for outputting an output parameter (280), a control system operably connected to the chemical loop and having a multiple controller part (230) comprising a model-free controller. The control system receives the output parameter (280), optimizes the input parameter (270) based on the received output parameter (280), and outputs an optimized input parameter (270) to the input of the chemical loop to control a process of the chemical loop in an optimized manner.

  3. Internet congestion control

    CERN Document Server

    Varma, Subir

    2015-01-01

    Internet Congestion Control provides a description of some of the most important topics in the area of congestion control in computer networks, with special emphasis on the analytical modeling of congestion control algorithms. The field of congestion control has seen many notable advances in recent years and the purpose of this book, which is targeted towards the advanced and intermediate reader, is to inform about the most important developments in this area. The book should enable the reader to gain a good understanding of the application of congestion control theory to a number of applic

  4. Self control in diabetics

    OpenAIRE

    Suljić, E.; Alajbegović, A.; B. Heljić; S. Alajbegović; Resić, H.

    2007-01-01

    The aim of this study was to determine to what extent patients in Zenica-Doboj Canton suffering from diabetes conducted self-control of glycemia and glycosuria, what was a weekly average of glycemia self-control and frequency of feet self-control. In 278 patients suffering from diabetes (58 with type 1 diabetes 1 and 220 with type 2 diabetes) we studied a conduct of self-control with these parameters in 1999 and 2004. In 1999 self-control of glycemia was conducted by 44.83% persons with type ...

  5. Measuring Self-Control

    OpenAIRE

    John Ameriks; Andrew Caplin; John Leahy; Tom Tyler

    2004-01-01

    How significant are individual differences in self-control? Do these differences impact wealth accumulation? From where do they derive? Our survey-based measure of self-control provides insights into all three questions: 1.There are individual differences in self-control not only of a quantitative but also of a qualitative nature. In our sample, standard self-control problems of over-consumption are no more prevalent than are problems of under-consumption. 2.Standard self-control problems do ...

  6. Optimal magnetic attitude control

    DEFF Research Database (Denmark)

    Wisniewski, Rafal; Markley, F.L.

    1999-01-01

    because control torques can only be generated perpendicular to the local geomagnetic field vector. This has been a serious obstacle for using magnetorquer based control for three-axis stabilization of a low earth orbit satellite. The problem of controlling the spacecraft attitude using only magnetic......Magnetic torquing is attractive as means of control for small satellites. The actuation principle is to use the interaction between the earth's magnetic field and a magnetic field generated by a coil set in the satellite. This control principle is inherently time-varying, and difficult to use...

  7. Customs control of goods

    Directory of Open Access Journals (Sweden)

    Mentor Gashi

    2015-11-01

    Full Text Available Customs control, is regulated by law in different countries. Different countries define through the law, the control of goods.. Main purpose of this paper is to analyze two types of customs controls, and their effect in reducing avoidance of duty or tax evasion which may be caused by the import of goods of certain companies. For this reason we researched which model is implemented in developing countries and what results were reached through questionnaires. In this sense the next research question, consists in defining the moment of customs control pre or post-clearance control of goods.

  8. Combat damage control surgery.

    Science.gov (United States)

    Blackbourne, Lorne H

    2008-07-01

    Although the use of damage control surgery for blunt and penetrating injury has been widely reported and defined, the use of damage control surgery on the battlefield (combat damage control surgery) has not been well detailed. Damage control surgery is now well established as the standard of care for severely injured civilian patients requiring emergent laparotomy in the United States. The civilian damage control paradigm is based on a "damage control trilogy." This trilogy comprises an abbreviated operation, intensive care unit resuscitation, and a return to the operating room for the definitive operation. The goal of damage control surgery and the triology is avoidance of irreversible physiological insult termed the lethal triad. The lethal triad comprises the vicious cycle of hypothermia, acidosis, and coagulopathy. Although the damage control model involves the damage control trilogy, abbreviated operation, intensive care unit resuscitation, and definitive operation, all in the same surgical facility, the combat damage control paradigm must incorporate global evacuation through several military surgical facilities and involves up to ten stages to allow for battlefield evacuation, surgical operations, multiple resuscitations, and transcontinental transport. Combat damage control surgery represents many unique challenges for those who care for the severely injured patients in a combat zone.

  9. Control, salud y bienestar

    Directory of Open Access Journals (Sweden)

    Salas-Auvert, Jesús A.

    2008-09-01

    Full Text Available En resumen, a pesar de que en algunas circunstancias, la exagerada percepción o necesidad de control es contraproducente para la adaptación y crecimiento psicológico, la aceptación general es que, al menos en grado moderado, el control percibido y control real son beneficios para las personas y un recurso valioso para enfrentar las dificultades en la vida. Por ello, las personas, grupos y naciones buscan sentirse dueñas de sus destinos y no víctimas de las circunstancias. Las personas y los pueblos con control son las que moldean y transforman las circunstacias, los que construyen un futuro mejor. Por ello, con objetivos preventivos y remediativos, los profesionales de la salud mental debemos promover el desarrollo y optimizacion de un control moderado y flexible como nutriente del crecimiento psicológico y bienestar biopsicosocial individual y colectivo. El trabajo aborda el significado del control, el desarrollo del control real y percibido, la relación entre control, salud y enfermedad, control, bienestar y psicopatología, la renuncia a los intentos de control, y control y terapia cognitivo-conductual.

  10. Control in Complex Organizations

    DEFF Research Database (Denmark)

    Rennstam, Jens; Kärreman, Dan

    The extant research on organizational control builds on the assumption of vertical control – managers are thought to develop orders, rules and norms to control the operating core. Yet it is claimed that work becomes increasingly “knowledge intensive” and that organizations rely heavily for their ......The extant research on organizational control builds on the assumption of vertical control – managers are thought to develop orders, rules and norms to control the operating core. Yet it is claimed that work becomes increasingly “knowledge intensive” and that organizations rely heavily......, and the concepts of constructive disobedience, translation, and peer reviewing as ways of understanding how control work is exercised at the operative level....

  11. Advanced AC Motor Control

    Energy Technology Data Exchange (ETDEWEB)

    Kazmierkowski, M.P. [Institute of Control and Industrial Electronics, Warsaw University of Technology, Warszawa (Poland)

    1997-12-31

    In this paper a review of control methods for high performance PWM inverter-fed induction motor drives is presented. Starting from the description of an induction motor by the help of the space vectors, three basic control strategic are discussed. As first, the most popular Field Oriented Control (FOC) is described. Secondly, the Direct Torque and Flux vector Control (DTFC) method, which - in contrast to FOC - depart from idea of coordinate transformation and analogy with DC motor, is briefly characterized. The last group is based on Feedback Linearization Control (FLC) and can be easy combined with sliding mode control. The simulation and experimental oscillograms that illustrate the performance of the discussed control strategies are shown. (orig.) 35 refs.

  12. Controlling chaos faster

    Energy Technology Data Exchange (ETDEWEB)

    Bick, Christian [Network Dynamics, Max Planck Institute for Dynamics and Self-Organization (MPIDS), 37077 Göttingen (Germany); Bernstein Center for Computational Neuroscience (BCCN), 37077 Göttingen (Germany); Institute for Mathematics, Georg–August–Universität Göttingen, 37073 Göttingen (Germany); Kolodziejski, Christoph [Network Dynamics, Max Planck Institute for Dynamics and Self-Organization (MPIDS), 37077 Göttingen (Germany); III. Physical Institute—Biophysics, Georg–August–Universität Göttingen, 37077 Göttingen (Germany); Timme, Marc [Network Dynamics, Max Planck Institute for Dynamics and Self-Organization (MPIDS), 37077 Göttingen (Germany); Institute for Nonlinear Dynamics, Georg–August–Universität Göttingen, 37077 Göttingen (Germany)

    2014-09-01

    Predictive feedback control is an easy-to-implement method to stabilize unknown unstable periodic orbits in chaotic dynamical systems. Predictive feedback control is severely limited because asymptotic convergence speed decreases with stronger instabilities which in turn are typical for larger target periods, rendering it harder to effectively stabilize periodic orbits of large period. Here, we study stalled chaos control, where the application of control is stalled to make use of the chaotic, uncontrolled dynamics, and introduce an adaptation paradigm to overcome this limitation and speed up convergence. This modified control scheme is not only capable of stabilizing more periodic orbits than the original predictive feedback control but also speeds up convergence for typical chaotic maps, as illustrated in both theory and application. The proposed adaptation scheme provides a way to tune parameters online, yielding a broadly applicable, fast chaos control that converges reliably, even for periodic orbits of large period.

  13. Motion control systems

    CERN Document Server

    Sabanovic, Asif

    2011-01-01

    "Presents a unified approach to the fundamental issues in motion control, starting from the basics and moving through single degree of freedom and multi-degree of freedom systems In Motion Control Systems, Šabanovic and Ohnishi present a unified approach to very diverse issues covered in motion control systems, offering know-how accumulated through work on very diverse problems into a comprehensive, integrated approach suitable for application in high demanding high-tech products. It covers material from single degree of freedom systems to complex multi-body non-redundant and redundant systems. The discussion of the main subject is based on original research results and will give treatment of the issues in motion control in the framework of the acceleration control method with disturbance rejection technique. This allows consistent unification of different issues in motion control ranging from simple trajectory tracking to topics related to haptics and bilateral control without and with delay in the measure...

  14. The Parrot UAV Controlled by PID Controllers

    Directory of Open Access Journals (Sweden)

    Koszewnik Andrzej

    2014-08-01

    Full Text Available The paper presents the process of modeling and designing control laws for four-rotor type of the Parrot UAV. The state space model is obtained by using several phenomena like gyroscopic effects for rigid bodies, propellers and rotors. The obtained model has been used to design PID control laws for roll, pitch, yaw angle and altitude, respectively. The numerical simulations of the closed loop model are shown that system in satisfy way stabilize flight of the quadro-rotor in all considered directions.

  15. The Parrot UAV Controlled by PID Controllers

    OpenAIRE

    Koszewnik Andrzej

    2014-01-01

    The paper presents the process of modeling and designing control laws for four-rotor type of the Parrot UAV. The state space model is obtained by using several phenomena like gyroscopic effects for rigid bodies, propellers and rotors. The obtained model has been used to design PID control laws for roll, pitch, yaw angle and altitude, respectively. The numerical simulations of the closed loop model are shown that system in satisfy way stabilize flight of the quadro-rotor in all considered dire...

  16. Instructional Prescriptions for Learner Control.

    Science.gov (United States)

    Chung, Jaesam; Reigeluth, Charles M.

    1992-01-01

    Discussion of learner control in instructional management describes six learner control methods: (1) content control; (2) sequence control; (3) pace control; (4) display or strategy control; (5) internal processing control; and (6) advisor strategies. Relevant literature, both theoretical and empirical, is reviewed, and learner control and…

  17. Contouring controller for precise motion control systems

    OpenAIRE

    Golubovic, Edin; Baran, Eray Abdurrahman; Şabanoviç, Asif; Sabanovic, Asif

    2013-01-01

    This paper discusses the trajectory generation algorithm, contour error construction method and finally the contour controller design. In the trajectory generation algorithm combination of elliptical Fourier descriptors (EFD) and time based spline approximation (TBSA) is used to generate position, velocity and acceleration references.Contour error is constructed using transformation of trajectory tracking errors. Transformation is computationally efficient and requires only reference velocity...

  18. Controllability of Complex Networks

    Science.gov (United States)

    Liu, Yang; Slotine, Jean-Jacques; Barabasi, Albert-Laszlo

    2011-03-01

    The ultimate proof of our understanding of natural or technological systems is reflected in our ability to control them. While control theory offers mathematical tools to steer engineered systems towards a desired state, we lack a general framework to control complex self-organized systems, like the regulatory network of a cell or the Internet. Here we develop analytical tools to study the controllability of an arbitrary complex directed network, identifying the set of driver nodes whose time-dependent control can guide the system's dynamics. We apply these tools to real and model networks, finding that sparse inhomogeneous networks, which emerge in many real complex systems, are the most difficult to control. In contrast, dense and homogeneous networks can be controlled via a few driver nodes. Counterintuitively, we find that in both model and real systems the driver nodes tend to avoid the hubs. We show that the robustness of control to link failure is determined by a core percolation problem, helping us understand why many complex systems are relatively insensitive to link deletion. The developed approach offers a framework to address the controllability of an arbitrary network, representing a key step towards the eventual control of complex systems.

  19. Advanced Control Strategies of Induction Machine: Field Oriented Control, Direct Torque Control and Model Predictive Control

    Directory of Open Access Journals (Sweden)

    Fengxiang Wang

    2018-01-01

    Full Text Available Field oriented control (FOC, direct torque control (DTC and finite set model predictive control (FS-MPC are different strategies for high performance electrical drive systems. FOC uses linear controllers and pulse width modulation (PWM to control the fundamental components of the load voltages. On the other hand, DTC and FS-MPC are nonlinear strategies that generate directly the voltage vectors in the absence of a modulator. This paper presents all three methods starting from theoretic operating principles, control structures and implementation. Experimental assessment is performed to discuss their advantages and limitations in detail. As main conclusions of this work, it is affirmed that different strategies have their own merits and all meet the requirements of modern high performance drives.

  20. Applied Control Systems Design

    CERN Document Server

    Mahmoud, Magdi S

    2012-01-01

    Applied Control System Design examines several methods for building up systems models based on real experimental data from typical industrial processes and incorporating system identification techniques. The text takes a comparative approach to the models derived in this way judging their suitability for use in different systems and under different operational circumstances. A broad spectrum of control methods including various forms of filtering, feedback and feedforward control is applied to the models and the guidelines derived from the closed-loop responses are then composed into a concrete self-tested recipe to serve as a check-list for industrial engineers or control designers. System identification and control design are given equal weight in model derivation and testing to reflect their equality of importance in the proper design and optimization of high-performance control systems. Readers’ assimilation of the material discussed is assisted by the provision of problems and examples. Most of these e...

  1. Quality Control Applications

    CERN Document Server

    Chorafas, Dimitris N

    2013-01-01

    Quality control is a constant priority in electrical, mechanical, aeronautical, and nuclear engineering – as well as in the vast domain of electronics, from home appliances to computers and telecommunications. Quality Control Applications provides guidance and valuable insight into quality control policies; their methods, their implementation, constant observation and associated technical audits. What has previously been a mostly mathematical topic is translated here for engineers concerned with the practical implementation of quality control. Once the fundamentals of quality control are established, Quality Control Applications goes on to develop this knowledge and explain how to apply it in the most effective way. Techniques are described and supported using relevant, real-life, case studies to provide detail and clarity for those without a mathematical background. Among the many practical examples, two case studies dramatize the importance of quality assurance: A shot-by-shot analysis of the errors made ...

  2. Fuzzy logic controller optimization

    Science.gov (United States)

    Sepe, Jr., Raymond B; Miller, John Michael

    2004-03-23

    A method is provided for optimizing a rotating induction machine system fuzzy logic controller. The fuzzy logic controller has at least one input and at least one output. Each input accepts a machine system operating parameter. Each output produces at least one machine system control parameter. The fuzzy logic controller generates each output based on at least one input and on fuzzy logic decision parameters. Optimization begins by obtaining a set of data relating each control parameter to at least one operating parameter for each machine operating region. A model is constructed for each machine operating region based on the machine operating region data obtained. The fuzzy logic controller is simulated with at least one created model in a feedback loop from a fuzzy logic output to a fuzzy logic input. Fuzzy logic decision parameters are optimized based on the simulation.

  3. Tautological control systems

    CERN Document Server

    Lewis, Andrew D

    2014-01-01

    This brief presents a description of a new modelling framework for nonlinear/geometric control theory. The framework is intended to be—and shown to be—feedback-invariant. As such, Tautological Control Systems provides a platform for understanding fundamental structural problems in geometric control theory. Part of the novelty of the text stems from the variety of regularity classes, e.g., Lipschitz, finitely differentiable, smooth, real analytic, with which it deals in a comprehensive and unified manner. The treatment of the important real analytic class especially reflects recent work on real analytic topologies by the author. Applied mathematicians interested in nonlinear and geometric control theory will find this brief of interest as a starting point for work in which feedback invariance is important. Graduate students working in control theory may also find Tautological Control Systems to be a stimulating starting point for their research.

  4. Spacecraft momentum control systems

    CERN Document Server

    Leve, Frederick A; Peck, Mason A

    2015-01-01

    The goal of this book is to serve both as a practical technical reference and a resource for gaining a fuller understanding of the state of the art of spacecraft momentum control systems, specifically looking at control moment gyroscopes (CMGs). As a result, the subject matter includes theory, technology, and systems engineering. The authors combine material on system-level architecture of spacecraft that feature momentum-control systems with material about the momentum-control hardware and software. This also encompasses material on the theoretical and algorithmic approaches to the control of space vehicles with CMGs. In essence, CMGs are the attitude-control actuators that make contemporary highly agile spacecraft possible. The rise of commercial Earth imaging, the advances in privately built spacecraft (including small satellites), and the growing popularity of the subject matter in academic circles over the past decade argues that now is the time for an in-depth treatment of the topic. CMGs are augmented ...

  5. Control Multivariable por Desacoplo

    Directory of Open Access Journals (Sweden)

    Fernando Morilla

    2013-01-01

    Full Text Available Resumen: La interacción entre variables es una característica inherente de los procesos multivariables, que dificulta su operación y el diseño de sus sistemas de control. Bajo el paradigma de Control por desacoplo se agrupan un conjunto de metodologías, que tradicionalmente han estado orientadas a eliminar o reducir la interacción, y que recientemente algunos investigadores han reorientado con objetivos de solucionar un problema tan complejo como es el control multivariable. Parte del material descrito en este artículo es bien conocido en el campo del control de procesos, pero la mayor parte de él son resultados de varios años de investigación de los autores en los que han primado la generalización del problema, la búsqueda de soluciones de fácil implementación y la combinación de bloques elementales de control PID. Esta conjunción de intereses provoca que no siempre se pueda conseguir un desacoplo perfecto, pero que sí se pueda conseguir una considerable reducción de la interacción en el nivel básico de la pirámide de control, en beneficio de otros sistemas de control que ocupan niveles jerárquicos superiores. El artículo resume todos los aspectos básicos del Control por desacoplo y su aplicación a dos procesos representativos: una planta experimental de cuatro tanques acoplados y un modelo 4×4 de un sistema experimental de calefacción, ventilación y aire acondicionado. Abstract: The interaction between variables is inherent in multivariable processes and this fact may complicate their operation and control system design. Under the paradigm of decoupling control, several methodologies that traditionally have been addressed to cancel or reduce the interactions are gathered. Recently, this approach has been reoriented by several researchers with the aim to solve such a complex problem as the multivariable control. Parts of the material in this work are well known in the process control field; however, most of them are

  6. Artificial locomotion control

    DEFF Research Database (Denmark)

    Azevedo, Christine; Poignet, Philippe; Espiau, Bernard

    2004-01-01

    This paper concerns the simultaneous synthesis and control of walking gaits for biped robots. The goal is to propose an adaptable and reactive control law for two-legged machines. The problem is addressed with human locomotion as a reference. The starting point of our work is an analysis of human...... walking from descriptive (biomechanics) as well as explicative (neuroscience and physiology) points of view, the objective being to stress the relevant elements for the approach of robot control. The adopted principles are then: no joint trajectory tracking; explicit distinction and integration...... of postural and walking control; use of evolutive optimization objectives; on-line event handling and environment adaptation and anticipation. This leads to the synthesis of an original control scheme based on non-linear model predictive control: Trajectory Free NMPC. The movement is specified implicitly...

  7. Debt Out of Control

    DEFF Research Database (Denmark)

    Achtziger, Anja; Hubert, Marco; Kenning, Peter

    2015-01-01

    In a representative sample of the German population (n = 946), we explored the links between self-control, compulsive buying, and debts. Participants completed the self-control scale (Tangney, Boone, & Baumeister, 2004) and the German Addictive Buying Scale (Raab, Neuner, Reisch, & Scherhorn, 2005......). Additionally, they gave information about their real debts. It was observed that self-control was negatively related to debts while compulsive buying was positively related to debts. Detailed analyses revealed that the link between self-control and debts was fully mediated by compulsive buying. Finally......, there was a gender effect on compulsive buying: women were more prone to compulsive buying than men. Age also was significantly negatively related to compulsive buying and positively linked to self-control. Household income was not linked to self-control, compulsive buying, and debts. Implications for practice...

  8. Reset Control Systems

    CERN Document Server

    Baños, Alfonso

    2012-01-01

    Reset Control Systems addresses the analysis for reset control treating both its basic form which requires only that the state of the controller be reinitialized to zero (the reset action) each time the tracking error crosses zero (the reset condition), and some useful variations of the reset action (partial reset with fixed or variable reset percentage) and of the reset condition (fixed or variable reset band and anticipative reset). The issues regarding reset control – concepts and motivation; analysis tools; and the application of design methodologies to real-world examples – are given comprehensive coverage. The text opens with an historical perspective which moves from the seminal work of the Clegg integrator and Horowitz FORE to more recent approaches based on impulsive/hybrid control systems and explains the motivation for reset compensation. Preliminary material dealing with notation, basic definitions and results, and with the definition of the control problem under study is also included. The fo...

  9. Fault Tolerant Control Systems

    DEFF Research Database (Denmark)

    Bøgh, S.A.

    failures. It is often feasible to increase availability for these control loops by designing the control system to perform on-line detection and reconfiguration in case of faults before the safety system makes a close-down of the process. A general development methodology is given in the thesis......This thesis considered the development of fault tolerant control systems. The focus was on the category of automated processes that do not necessarily comprise a high number of identical sensors and actuators to maintain safe operation, but still have a potential for improving immunity to component...... that carried the control system designer through the steps necessary to consider fault handling in an early design phase. It was shown how an existing control loop with interface to the plant wide control system could be extended with three additional modules to obtain fault tolerance: Fault detection...

  10. Tagging vs. Controlled Vocabulary

    DEFF Research Database (Denmark)

    Bogers, Toine; Petras, Vivien

    2015-01-01

    elements like core bibliographic data, controlled vocabulary terms, reviews, and tags to the retrieval performance. Our comparison is done using a test collection of over 2 million book records with information elements from Amazon, the British Library, the Library of Congress, and LibraryThing. We find...... that tags and controlled vocabulary terms do not actually outperform each other consistently, but seem to provide complementary contributions: some information needs are best addressed using controlled vocabulary terms whereas other are best addressed using tags....

  11. ISTTOK control system upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Ivo S., E-mail: ivoc@ipfn.ist.utl.pt; Duarte, Paulo; Fernandes, Horácio; Valcárcel, Daniel F.; Carvalho, Pedro J.; Silva, Carlos; Duarte, André S.; Neto, André; Sousa, Jorge; Batista, António J.N.; Carvalho, Bernardo B.

    2013-10-15

    Highlights: •ISTTOK fast controller. •All real-time diagnostic and actuators were integrated in the control platform. •100 μs control cycle under the MARTe framework. •The ISTTOK control system upgrade provides reliable operation with an improved operational space. -- Abstract: The ISTTOK tokamak (Ip = 4 kA, BT = 0.5 T, R = 0.46 m, a = 0.085 m) is one of the few tokamaks with regular alternate plasma current (AC) discharges scientific programme. In order to improve the discharge stability and to increase the number of AC discharge cycles a novel control system was developed. The controller acquires data from 50 analog-to-digital converter (ADC) channels of real-time diagnostics and measurements: tomography, Mirnov coils, interferometer, electric probes, sine and cosine probes, bolometer, current delivered by the power supplies, loop voltage and plasma current. The system has a control cycle of 100 μs during which it reads all the diagnostics connected to the advanced telecommunications computing architecture (ATCA) digitizers and sends the control reference to ISTTOK actuators. The controller algorithms are executed on an Intel{sup ®} Q8200 chip with 4 cores running at 2.33 GHz and connected to the I/O interfaces through an ATCA based environment. The real-time control system was programmed in C++ on top of the Multi-threaded Application Real-Time executor (MARTe). To extend the duration of the AC discharges and the plasma stability a new magnetising field power supply was commissioned and the horizontal and vertical field power supplies were also upgraded. The new system also features a user-friendly interface based on HyperText Markup Language (HTML) and Javascript to configure the controller parameters. This paper presents the ISTTOK control system and the consequent update of real-time diagnostics and actuators.

  12. Modular Battery Controller

    Science.gov (United States)

    Button, Robert M (Inventor); Gonzalez, Marcelo C (Inventor)

    2017-01-01

    Some embodiments of the present invention describe a battery including a plurality of master-less controllers. Each controller is operatively connected to a corresponding cell in a string of cells, and each controller is configured to bypass a fraction of current around the corresponding cell when the corresponding cell has a greater charge than one or more other cells in the string of cells.

  13. Temperature measurement and control

    CERN Document Server

    Leigh, JR

    1988-01-01

    This book treats the theory and practice of temperature measurement and control and important related topics such as energy management and air pollution. There are no specific prerequisites for the book although a knowledge of elementary control theory could be useful. The first half of the book is an application oriented survey of temperature measurement techniques and devices. The second half is concerned mainly with temperature control in both simple and complex situations.

  14. SDN controllers security issues

    OpenAIRE

    Imran, Ayesha

    2017-01-01

    Software-Defined Networking (SDN) is essentially varying the way we design and manage networks, which makes a communication network programmable. In SDN, a logically centralized controller has straight control over the packet-handling functions of the network switches, using a standard, open API (Application Programming Interface) such as OpenFlow. OpenFlow is a broadly used protocol for software-defined networks (SDNs) that presents a new model in which the control plane is inattentive from ...

  15. Unpacking Self-Control

    OpenAIRE

    Duckworth, Angela; Steinberg, Laurence

    2015-01-01

    Self-controlled behavior refers to actions aligned with valued, longer-term goals in the face of conflicting impulses to seek immediate gratification. In this article, we argue that the psychological processes that contribute to self-controlled behavior can be grouped into two functionally distinct categories: Volitional processes facilitate self-controlled behavior and include executive functions as well as learned metacognitive strategies like planning, attention deployment, and psychologic...

  16. Intelligent PID controllers

    OpenAIRE

    Fliess, Michel; Join, Cédric

    2008-01-01

    International audience; Intelligent PID controllers, or i-PID controllers, are PID controllers where the unknown parts of the plant, which might be highly nonlinear and/or time-varying, are taken into account without any modeling procedure. Our main tool is an online numerical differentiator, which is based on easily implementable fast estimation and identification techniques. Several numerical experiments demonstrate the efficiency of our method when compared to more classic PID regulators.

  17. Molluscicides in schistosomiasis control

    OpenAIRE

    McCullough, F. S.; Gayral, Ph.; DUNCAN, J; Christie, J. D.

    1980-01-01

    Although mollusciciding can be a cost-effective method of controlling schistosomiasis transmission, only one organic molluscicide, niclosamide, is now being produced commercially, and only a few compounds are at present being tested in the laboratory. In future, improved cost-effective use of molluscicides will require more precise knowledge of schistosomiasis transmission patterns in each endemic area and improved application techniques. In snail control studies using controlled-release form...

  18. Statistical Engine Knock Control

    DEFF Research Database (Denmark)

    Stotsky, Alexander A.

    2008-01-01

    A new statistical concept of the knock control of a spark ignition automotive engine is proposed . The control aim is associated with the statistical hy pothesis test which compares the threshold value to the average value of the max imal amplitud e of the knock sensor signal at a given freq uency...... which includ es generation of the amplitud e signals, a threshold value d etermination and a knock sound mod el is d eveloped for evaluation of the control concept....

  19. Gun Control Legislation

    Science.gov (United States)

    2010-03-10

    for and against greater gun control . Past legislative proposals have raised the following questions: What restrictions on firearms are permissible...under the Constitution? Does gun control help reduce violent crime? Would household, street corner, and schoolyard disputes be less lethal if firearms...were more difficult to acquire? Or, would more restrictive gun control policies diminish an individual’s ability to defend himself? Speaking to these

  20. Computer aided manipulator control

    Science.gov (United States)

    Bejczy, A. K.; Zawacki, R. L.

    1980-01-01

    This paper describes the hardware and software system of a dedicated mini- and microcomputer network developed at the JPL teleoperator project to aid the operator in real-time control of remote manipulators. The operator can be in series or in parallel with the control computer during operation. The purpose of the project is to develop, demonstrate and evaluate advanced supervisory control concepts and techniques for space applications. The paper concludes with a brief outline of future development plans and issues.

  1. Biomechanics in Molar Control

    OpenAIRE

    Rendón Giraldo, Juan Esteban; Castaño, Gabriel

    2014-01-01

    Inadequate molar control is one of the difficulties that arise during mechanical treatment. When molar control is handled efficiently, it facilitates precise control of forces and moments, which increases the effectiveness of biomechanics. Knowledge of 4 x 2, 6 x 2 partial systems and the transpalatal bar with its different forms of activation offer a number of advantages that make it possible to optimize orthodontic results. The aim of this article is to clarify concepts, specify possible tr...

  2. Proxemic-aware controls

    DEFF Research Database (Denmark)

    Ledo, David; Greenberg, Saul; Marquardt, Nicolai

    2015-01-01

    Remote controls facilitate interactions at-a-distance with appliances. However, the complexity, diversity, and in-creasing number of digital appliances in ubiquitous com-puting ecologies make it increasingly difficult to: (1) dis-cover which appliances are controllable; (2) select a par...... to create a dynamic appliance control interface. Specifically, a person can discover and select an appliance by the way one orients a mobile device around the room, and then progressively view the appliance's status and control its features in in-creasing detail by simply moving towards it. We illus...

  3. Control systems engineering

    CERN Document Server

    Nise, Norman S

    1995-01-01

    This completely updated new edition shows how to use MATLAB to perform control-system calculations. Designed for the professional or engineering student who needs a quick and readable update on designing control systems, the text features a series of tightly focused examples that clearly illustrate each concept of designing control systems. Most chapters conclude with a detailed application from the two case studies that run throughout the book: an antenna asimuth control system and a submarine. The author also refers to many examples of design methods.

  4. Detonation command and control

    Science.gov (United States)

    Mace, Jonathan L.; Seitz, Gerald J.; Echave, John A.; Le Bas, Pierre-Yves

    2016-05-31

    The detonation of one or more explosive charges and propellant charges by a detonator in response to a fire control signal from a command and control system comprised of a command center and instrumentation center with a communications link there between. The fire control signal is selectively provided to the detonator from the instrumentation center if plural detonation control switches at the command center are in a fire authorization status, and instruments, and one or more interlocks, if included, are in a ready for firing status. The instrumentation and command centers are desirably mobile, such as being respective vehicles.

  5. Detonation command and control

    Energy Technology Data Exchange (ETDEWEB)

    Mace, Jonathan L.; Seitz, Gerald J.; Echave, John A.; Le Bas, Pierre-Yves

    2015-11-10

    The detonation of one or more explosive charges and propellant charges by a detonator in response to a fire control signal from a command and control system comprised of a command center and instrumentation center with a communications link therebetween. The fire control signal is selectively provided to the detonator from the instrumentation center if plural detonation control switches at the command center are in a fire authorization status, and instruments, and one or more interlocks, if included, are in a ready for firing status. The instrumentation and command centers are desirably mobile, such as being respective vehicles.

  6. Computer aided control engineering

    DEFF Research Database (Denmark)

    Szymkat, Maciej; Ravn, Ole

    1997-01-01

    Current developments in the field of Computer Aided Control Engineering (CACE) have a visible impact on the design methodologies and the structure of the software tools supporting them. Today control engineers has at their disposal libraries, packages or programming environments that may be speci......Current developments in the field of Computer Aided Control Engineering (CACE) have a visible impact on the design methodologies and the structure of the software tools supporting them. Today control engineers has at their disposal libraries, packages or programming environments that may...

  7. ALFA Detector Control System

    CERN Document Server

    Oleiro Seabra, Luis Filipe; The ATLAS collaboration

    2015-01-01

    ALFA (Absolute Luminosity For ATLAS) is one of the sub-detectors of ATLAS/LHC. The ALFA system is composed by two stations installed in the LHC tunnel 240 m away from each side of the ATLAS interaction point. Each station has a vacuum and ventilation system, movement control and all the required electronic for signal processing. The Detector Control System (DCS) provides control and monitoring of several components and ensures the safe operation of the detector contributing to good Data Quality. This paper describes the ALFA DCS system including a detector overview, operation aspects and hardware control through a SCADA system, WinCC OA.

  8. Ship Roll Motion Control

    DEFF Research Database (Denmark)

    Perez, Tristan; Blanke, Mogens

    2010-01-01

    The technical feasibility of roll motion control devices has been amply demonstrated for over 100 years. Performance, however, can still fall short of expectations because of deciencies in control system designs, which have proven to be far from trivial due to fundamental performance limitations....... This tutorial paper presents an account of the development of various ship roll motion control systems and the challenges associated with their design. The paper discusses how to assess performance, the applicability of dierent models, and control methods that have been applied in the past....

  9. Detonation command and control

    Energy Technology Data Exchange (ETDEWEB)

    Mace, Jonathan Lee; Seitz, Gerald J.; Echave, John A.; Le Bas, Pierre-Yves

    2017-12-05

    The detonation of one or more explosive charges and propellant charges by a detonator in response to a fire control signal from a command and control system comprised of a command center and instrumentation center with a communications link therebetween. The fire control signal is selectively provided to the detonator from the instrumentation center if plural detonation control switches at the command center are in a fire authorization status, and instruments, and one or more interlocks, if included, are in a ready for firing status. The instrumentation and command centers are desirably mobile, such as being respective vehicles.

  10. Device Oriented Project Controller

    Energy Technology Data Exchange (ETDEWEB)

    Dalesio, Leo; Kraimer, Martin

    2013-11-20

    This proposal is directed at the issue of developing control systems for very large HEP projects. A de-facto standard in accelerator control is the Experimental Physics and Industrial Control System (EPICS), which has been applied successfully to many physics projects. EPICS is a channel based system that requires that each channel of each device be configured and controlled. In Phase I, the feasibility of a device oriented extension to the distributed channel database was demonstrated by prototyping a device aware version of an EPICS I/O controller that functions with the current version of the channel access communication protocol. Extensions have been made to the grammar to define the database. Only a multi-stage position controller with limit switches was developed in the demonstration, but the grammar should support a full range of functional record types. In phase II, a full set of record types will be developed to support all existing record types, a set of process control functions for closed loop control, and support for experimental beam line control. A tool to configure these records will be developed. A communication protocol will be developed or extensions will be made to Channel Access to support introspection of components of a device. Performance bench marks will be made on both communication protocol and the database. After these records and performance tests are under way, a second of the grammar will be undertaken.

  11. Control system design guide

    Energy Technology Data Exchange (ETDEWEB)

    Sellers, David; Friedman, Hannah; Haasl, Tudi; Bourassa, Norman; Piette, Mary Ann

    2003-05-01

    The ''Control System Design Guide'' (Design Guide) provides methods and recommendations for the control system design process and control point selection and installation. Control systems are often the most problematic system in a building. A good design process that takes into account maintenance, operation, and commissioning can lead to a smoothly operating and efficient building. To this end, the Design Guide provides a toolbox of templates for improving control system design and specification. HVAC designers are the primary audience for the Design Guide. The control design process it presents will help produce well-designed control systems that achieve efficient and robust operation. The spreadsheet examples for control valve schedules, damper schedules, and points lists can streamline the use of the control system design concepts set forth in the Design Guide by providing convenient starting points from which designers can build. Although each reader brings their own unique questions to the text, the Design Guide contains information that designers, commissioning providers, operators, and owners will find useful.

  12. Intelligent networked teleoperation control

    CERN Document Server

    Li, Zhijun; Su, Chun-Yi

    2015-01-01

    This book describes a unified framework for networked teleoperation systems involving multiple research fields: networked control systems for linear and nonlinear forms, bilateral teleoperation, trilateral teleoperation, multilateral teleoperation and cooperative teleoperation. It closely examines networked control as a field at the intersection of systems & control and robotics and presents a number of experimental case studies on testbeds for robotic systems, including networked haptic devices, robotic network systems and sensor network systems. The concepts and results outlined are easy to understand, even for readers fairly new to the subject. As such, the book offers a valuable reference work for researchers and engineers in the fields of systems & control and robotics.

  13. Automatic control of bioprocesses.

    Science.gov (United States)

    Stanke, Marc; Hitzmann, Bernd

    2013-01-01

    In this chapter, different approaches for open-loop and closed-loop control applied in bioprocess automation are discussed. Although in recent years many contributions dealing with closed-loop control have been published, only a minority were actually applied in real bioprocesses, the majority being simulations. As a result of the diversity of bioprocess requirements, a single control algorithm cannot be applied in all cases; rather, different approaches are necessary. Most publications combine different closed-loop control techniques to construct hybrid systems. These systems are supposed to combine the advantages of each approach into a well-performing control strategy. The majority of applications are soft sensors in combination with a proportional-integral-derivative (PID) controller. The fact that soft sensors have become this importance for control purposes demonstrates the lack of direct measurements or their large additional expense for robust and reliable online measurement systems. The importance of model predictive control is increasing; however, reliable and robust process models are required, as well as very powerful computers to address the computational needs. The lack of theoretical bioprocess models is compensated by hybrid systems combining theoretical models, fuzzy logic, and/or artificial neural network methodology. Although many authors suggest a possible transfer of their presented control application to other bioprocesses, the algorithms are mostly specialized to certain organisms or certain cultivation conditions as well as to a specific measurement system.

  14. Control functions in MFM

    DEFF Research Database (Denmark)

    Lind, Morten

    2011-01-01

    Multilevel Flow Modeling (MFM) has been proposed as a tool for representing goals and functions of complex industrial plants and suggested as a basis for reasoning about control situations. Lind presents an introduction to MFM but do not describe how control functions are used in the modeling....... The purpose of the present paper is to serve as a companion paper to this introduction by explaining the basic principles used in MFM for representation of control functions. A theoretical foundation for modeling control functions is presented and modeling examples are given for illustration....

  15. ALFA Detector Control System

    CERN Document Server

    Oleiro Seabra, Luis Filipe; The ATLAS collaboration

    2015-01-01

    ALFA (Absolute Luminosity For ATLAS) is one of the sub-detectors of ATLAS (A Toroidal LHC Apparatus). The ALFA system is composed by four stations installed in the LHC tunnel 240 m away from the ATLAS interaction point. Each station has a vacuum and ventilation system, movement control and all the required electronics for signal processing. The Detector Control System (DCS) provides control and monitoring of several components and ensures the safe operation of the detector contributing to good Data Quality. This paper describes the ALFA DCS system including a detector overview, operation aspects and hardware control through a SCADA system, WinCC OA.

  16. MOSFET Power Controller

    Science.gov (United States)

    Mitchell, J.; Jones, K.

    1986-01-01

    High current and voltage controlled remotely. Remote Power Conroller includes two series-connected banks of parallel-connected MOSFET's to withstand high current and voltage. Voltage sharing between switch banks, low-impedance, gate-drive circuits used. Provided controlled range for turn on. Individually trimmable to insure simultaneous switching within few nanoseconds during both turn on and turn off. Control circuit for each switch bank and over-current trip circuit float independently and supplied power via transformer T1 from inverter. Control of floating stages by optocouplers.

  17. Records Control Schedules Repository

    Data.gov (United States)

    National Archives and Records Administration — The Records Control Schedules (RCS) repository provides access to scanned versions of records schedules, or Standard Form 115, Request for Records Disposition...

  18. Advanced Control Engineering

    DEFF Research Database (Denmark)

    Zhou, Jianjun

    1999-01-01

    This book is developed as a textbook for the course Advanced Control Engineering. The book is intended for students in mechanical engineering and its aim is to provide an understanding of modern control theory as well as methodologies and applications for state space modeling and design....... For this reason, the book puts emphasis on the state-space approach. The main contents of the book includes state-space representation of dynamic systems, analysis of linear control systems, feedback control and observer design. Both continuous-time and discrete-time systems have been addressed in this book....

  19. Internal Control: Peran Dan Perkembangannya

    OpenAIRE

    Murtin, Alek

    2000-01-01

    Perhatian terhadap pentingnya internal control dalam organisasi berjalan dari waktu ke waktu untuk meningkatkan fungsi internal control yang disesuaikan dengan perkembangan lingkungan organisasi, dimulai dengan adanya internal check, kemudian internal control system, internal control structure dan terakhir adalah internal control-integrated framework. Internal control system sempat berkembang beberapa tahun di Indonesia yang selanjutnya digantikan oleh internal control structure yang digunaka...

  20. MODEL PREDICTIVE CONTROL FUNDAMENTALS

    African Journals Online (AJOL)

    2012-07-02

    Jul 2, 2012 ... written to simulate an example of a randomly generated system. This paper can serve as tutorial to anyone interested in this area of research. Keywords: model predictive control, linear systems, discrete-time systems, constraints, quadratic programming. 1. Introduction. Model Predictive Control (MPC), also ...

  1. Individual tree control

    Science.gov (United States)

    Harvey A. Holt

    1989-01-01

    Controlling individual unwanted trees in forest stands is a readily accepted method for improving the value of future harvests. The practice is especially important in mixed hardwood forests where species differ considerably in value and within species individual trees differ in quality. Individual stem control is a mechanical or chemical weeding operation that...

  2. Optimal vehicle control

    NARCIS (Netherlands)

    Alirezaei, M.; Kanarachos, S.A.; Scheepers, B.T.M.; Maurice, J.P.

    2013-01-01

    The Integrated Vehicle Safety Department of TNO (Dutch Organization for Applied Scientific Research) investigates the application of modern control methods in the Integrated Vehicle Dynamics Control (IVDC) field, as a strategic research topic of the Beyond Safe framework. The aim of IVDC is to

  3. Balancing Trust and Control

    DEFF Research Database (Denmark)

    Jagd, Søren

    This paper focuses on the leadership challenge of balancing trust and control. The relation between trust and control has for a long time been a puzzling issue for management researchers. In the paper I first show that there has been a dramatic change in the way the relation between trust and con...

  4. NUCLEAR REACTOR CONTROL SYSTEM

    Science.gov (United States)

    Epler, E.P.; Hanauer, S.H.; Oakes, L.C.

    1959-11-01

    A control system is described for a nuclear reactor using enriched uranium fuel of the type of the swimming pool and other heterogeneous nuclear reactors. Circuits are included for automatically removing and inserting the control rods during the course of normal operation. Appropriate safety circuits close down the nuclear reactor in the event of emergency.

  5. Encyclopedia of Birth Control.

    Science.gov (United States)

    Rengel, Marian

    This encyclopedia brings together in more than 200 entries, arranged in A-to-Z format, a portrait of the complex modern issue that birth control has become with advances in medicine and biochemistry during the 20th century. It is aimed at both the student and the consumer of birth control. Entries cover the following topics: birth control…

  6. Ship Roll Damping Control

    DEFF Research Database (Denmark)

    Perez, Tristan; Blanke, Mogens

    2012-01-01

    The technical feasibility of roll motion control devices has been amply demonstrated for over 100 years. Performance, however, can still fall short of expectations because of difficulties associated with control system designs, which have proven to be far from trivial due to fundamental performan...

  7. Modern process-control

    CERN Document Server

    Raich, Ulrich

    1991-01-01

    Today's control system architectures will be explained, using their historical development and advances in computer technologies as a guide. These developments will be documented with the example of CERN's accelerator control systems. Having an overview of current systems allows a closer look at the constituents: operator consoles, front-end computers, embedded processors and the networks and buses interconnecting them.

  8. Model Indepedent Vibration Control

    OpenAIRE

    Yuan, Jing

    2010-01-01

    A NMIFC system is proposed for broadband vibration control. It has two important features. Feature F1 is that the NMIFC is stable without introducing any invasive effects, such as probing signals or controller perturbations, into the vibration system; feature F2 is

  9. Counter Weapon Control

    Science.gov (United States)

    2015-03-26

    Laws”. Journal of Guidance, Control, and Dynamics, 4(2):109–115, 1981. 2. Baba, Yoriaki, Makoto Yamaguchi, and Robert M Howe. “Generalized Guid- ance...Line-of-Sight Intercept Guidance for Aircraft Defense”. Journal of Guidance, Control, and Dynamics, 36(3):898–902, 2013. 22. Yuan, Luke Chia -Liu

  10. Rethinking Coercive Control.

    Science.gov (United States)

    Stark, Evan

    2009-12-01

    The critical appraisals of Coercive Control focus largely on what my analysis implies for intervention, a matter to which the book devotes only limited space. In this reply, I reiterate core concepts in the book and acknowledge that much more work is needed to translate the realities of coercive control into practical legal and advocacy strategies. I review how coercive control differs from partner assaults and so why it merits a distinct response; the extent to which coercive control targets gender identity; the wisdom of complementing the focus on violence with an emphasis on male domination, sexual inequality and personal liberty; what this implies for shelters and the law; why sexual inequality differentiates coercive control from female partner abuse of men; how sexual equality can be both cause and antidote for coercive control; why I think an affirmative concept of freedom is essential to grasp the human rights violations inflicted by coercive control; and what it means to "story" coercive control by integrating women into the larger liberty narrative on which our national identity rests.

  11. Birth Control - Multiple Languages

    Science.gov (United States)

    ... PDF Birth Control Methods - myanma bhasa (Burmese) MP3 Family Tree Clinic Teen Wise Minnesota Chinese, Simplified (Mandarin dialect) ( ... Dari) PDF Birth Control Methods - دری (Dari) MP3 Family Tree Clinic Teen Wise Minnesota Farsi (فارسی) Expand Section ...

  12. Informal control code logic

    NARCIS (Netherlands)

    Bergstra, J.A.

    2010-01-01

    General definitions as well as rules of reasoning regarding control code production, distribution, deployment, and usage are described. The role of testing, trust, confidence and risk analysis is considered. A rationale for control code testing is sought and found for the case of safety critical

  13. Schistosomiasis control in Brazil

    Directory of Open Access Journals (Sweden)

    Katz Naftale

    1998-01-01

    Full Text Available In 1975 the Special Programme for Schistosomiasis Control was introduced in Brazil with the objective of controlling this parasitic disease in six northeastern states. The methodology applied varied largely from state to state, but was based mainly on chemotherapy, This Programme was modified about ten years after it beginning with the main goals including control of morbidity and the blockage of establishment of new foci in non-endemic areas. In two states, Bahia and Minas Gerais, the schistosomiasis control programme started in 1979 and 1983, respectively. The recently made evaluation of those two programmes is the main focus of this paper. It must also be pointed out, that the great majority of the studies performed by different researchers in Brazil, at different endemic areas, consistently found significant decrease on prevalence and incidence, when control measures are repeatedly used for several years. Significant decrease of hepatosplenic forms in the studied areas is well documented in Brazil. After more than 20 years of schistosomiasis control programmes in our country, chemotherapy has shown to be a very important tool for the control of morbidity and to decrease prevalence and incidence in endemic areas. Nevertheless, in medium and long terms, sanitation, water supply, sewage draining and health education seem to be the real tools when the aim is persistent and definitive schistosomiasis control.

  14. Control of schistosomiasis transmission

    Directory of Open Access Journals (Sweden)

    Luiz C. de S. Dias

    1995-04-01

    Full Text Available Despite the success of control programmes, schistosomiasis is still a serious public health problem in the world. More than 70 countries where 200 million individuals are evaluated to be infected of a total 600 million at risk. Though there have been important local success in the control of transmission, globally the infection has increased. Economic constrains in developing countries, environmental changes associated with migration and water resources development have been blocking the progress. The main objective of schistosomiasis control is to achieve reduction of disease due to schistosomiasis. We discussed the control measures like: health education, diagnosis and chemotherapy, safe water supplies, sanitation and snail control. We emphasized the need to give priority to school-age children and the importance of integrating the measures of control into locally available systems of health care. The control of schistosomiasis is directly related to the capacity of the preventive health services of an endemic country. The strategy of control requires long-term commitment from the international to the local level.

  15. Alcohol Locus of Control.

    Science.gov (United States)

    Johnson, Patrick B.; Reszka, Diane

    Research has shown that differences in perceived control can influence drinking behavior and alcoholic rehabilitation. This study examined the viability of an alcohol-specific locus of control scale. Undergraduate students (41 male and 40 female) completed a demographic questionnaire assessing age, sex, ethnicity, and drinking frequency; Rotter's…

  16. Analysing Access Control Specifications

    DEFF Research Database (Denmark)

    Probst, Christian W.; Hansen, René Rydhof

    2009-01-01

    . Recent events have revealed intimate knowledge of surveillance and control systems on the side of the attacker, making it often impossible to deduce the identity of an inside attacker from logged data. In this work we present an approach that analyses the access control configuration to identify the set...

  17. A dispersion control chart

    NARCIS (Netherlands)

    Riaz, M.

    2008-01-01

    The study proposes a Shewhart-type control chart, namely Q chart, based on inter-quartile range, for monitoring changes (especially of moderate and large amounts which is major concern of Shewhart-type control charts) in process dispersion assuming normality of quality characteristic to be

  18. PS Control Room

    CERN Multimedia

    CERN PhotoLab

    1963-01-01

    The good old PS Control Room, all manual. For each parameter, a knob or a button to control it; for each, a light or meter or oscilloscope to monitor it; carefully written pages serve as the data bank; phones and intercom for communication. D.Dekkers is at the microphone, M.Valvini sits in front.

  19. Resisting Mind Control.

    Science.gov (United States)

    Anderson, Susan M.; Zimbardo, Philip G.

    1980-01-01

    Provides conceptual analyses of mind control techniques along with practical advice on how to resist these techniques. The authors stress that effective mind control stems more from everyday social relations than from exotic technological gimmicks. Suggestions are given for resisting persuasion, resisting systems, and challenging the system.…

  20. Swashplate control system

    Science.gov (United States)

    Peyran, Richard J.; Laub, Georgene H.; Morse, H. Andrew

    1987-01-01

    A mechanical system to control the position of a rotating swashplate is developed. This system provides independent lateral cyclic, longitudinal cyclic and collective pitch control of a helicopter rotor attached to the swashplate, without use of a mixer box. The system also provide direct, linear readout of cyclic and collective swashplate positions.

  1. Contamination Control Techniques

    Energy Technology Data Exchange (ETDEWEB)

    EBY, J.L.

    2000-05-16

    Welcome to a workshop on contamination Control techniques. This work shop is designed for about two hours. Attendee participation is encouraged during the workshop. We will address different topics within contamination control techniques; present processes, products and equipment used here at Hanford and then open the floor to you, the attendees for your input on the topics.

  2. Fault Tolerant Feedback Control

    DEFF Research Database (Denmark)

    Stoustrup, Jakob; Niemann, H.

    2001-01-01

    An architecture for fault tolerant feedback controllers based on the Youla parameterization is suggested. It is shown that the Youla parameterization will give a residual vector directly in connection with the fault diagnosis part of the fault tolerant feedback controller. It turns out that there...

  3. Checking quality control?

    DEFF Research Database (Denmark)

    Brodersen, Lars

    2005-01-01

    How is quality control doing within the community of GIS, web-services based on geo-information, GI etc.?......How is quality control doing within the community of GIS, web-services based on geo-information, GI etc.?...

  4. Internal budget control

    Directory of Open Access Journals (Sweden)

    MSc. Mervete Shala

    2011-06-01

    Generally, duties of internal control officers within ministries and institutions must be clearly divided to reduce the risk of inco-rrect behaviour. Operations of an efficient control mechanism influence and ensure conditions for rule of law, good governance, and democracy.

  5. Gaze-controlled Driving

    DEFF Research Database (Denmark)

    Tall, Martin; Alapetite, Alexandre; San Agustin, Javier

    2009-01-01

    We investigate if the gaze (point of regard) can control a remote vehicle driving on a racing track. Five different input devices (on-screen buttons, mouse-pointing low-cost webcam eye tracker and two commercial eye tracking systems) provide heading and speed control on the scene view transmitted...

  6. AUTOMATIC INTRAVENOUS DRIP CONTROLLER*

    African Journals Online (AJOL)

    Both the nursing staff shortage and the need for precise control in the administration of dangerous drugs intra- venously have led to the development of various devices to achieve an automatic system. The continuous automatic control of the drip rate eliminates errors due to any physical effect such as movement of the ...

  7. Birth Control Methods

    Science.gov (United States)

    ... man to do. It takes a lot of self-control. Even if you use withdrawal, sperm can be ... 1–104. Food and Drug Administration. (2016). Birth Control: Medicines to Help You. Food and Drug Administration. (2013). FC2 Female condom . National Cancer Institute. (2012). Oral Contraceptives and Cancer Risk . Wright, ...

  8. Pattern Recognition Control Design

    Science.gov (United States)

    Gambone, Elisabeth A.

    2018-01-01

    Spacecraft control algorithms must know the expected vehicle response to any command to the available control effectors, such as reaction thrusters or torque devices. Spacecraft control system design approaches have traditionally relied on the estimated vehicle mass properties to determine the desired force and moment, as well as knowledge of the effector performance to efficiently control the spacecraft. A pattern recognition approach was used to investigate the relationship between the control effector commands and spacecraft responses. Instead of supplying the approximated vehicle properties and the thruster performance characteristics, a database of information relating the thruster ring commands and the desired vehicle response was used for closed-loop control. A Monte Carlo simulation data set of the spacecraft dynamic response to effector commands was analyzed to establish the influence a command has on the behavior of the spacecraft. A tool developed at NASA Johnson Space Center to analyze flight dynamics Monte Carlo data sets through pattern recognition methods was used to perform this analysis. Once a comprehensive data set relating spacecraft responses with commands was established, it was used in place of traditional control methods and gains set. This pattern recognition approach was compared with traditional control algorithms to determine the potential benefits and uses.

  9. IBM 3705 Communications Controller

    CERN Multimedia

    1972-01-01

    The IBM 3705 Communications Controller is a simple computer which attaches to an IBM System/360 or System/370. Its purpose is to connect communication lines to the mainframe channel. It was a first communications controller of the popular IBM 37xx series.

  10. Systems and Control Engineering

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 4; Issue 5. Systems and Control Engineering - Control Systems-Analysis and Design. A Rama Kalyan J R Vengateswaran. General Article Volume 4 Issue 5 May 1999 pp 88-94 ...

  11. Process control device

    Energy Technology Data Exchange (ETDEWEB)

    Hayashi, Toshifumi; Kobayashi, Hiroshi

    1994-09-09

    A process control device comprises a memory device for memorizing a plant operation target, a plant state or a state of equipments related with each other as control data, a read-only memory device for storing programs, a plant instrumentation control device or other process control devices, an input/output device for performing input/output with an operator, and a processing device which conducts processing in accordance with the program and sends a control demand or a display demand to the input/output device. The program reads out control data relative to a predetermined operation target, compares and verify them with actual values to read out control data to be a practice premise condition which is further to be a practice premise condition if necessary, thereby automatically controlling the plant or requiring or displaying input. Practice presuming conditions for the operation target can be examined succesively in accordance with the program without constituting complicated logical figures and AND/OR graphs. (N.H.).

  12. Robust Flight Controllers.

    Science.gov (United States)

    1983-12-01

    Institute of Technology, Wright-Patterson Air force Base, Ohio, December, 1982. 31. Roskam , J. Airplane Flight Dynamics and Automatic Flight Controls...Lawrence, Kansas: Roskam Aviation and Engineering, 1979. 171 " APPENDIX A: Generic Controller Format Al. Introduction In Chapter II, the idea of a

  13. Discrete control systems

    CERN Document Server

    Okuyama, Yoshifumi

    2014-01-01

    Discrete Control Systems establishes a basis for the analysis and design of discretized/quantized control systemsfor continuous physical systems. Beginning with the necessary mathematical foundations and system-model descriptions, the text moves on to derive a robust stability condition. To keep a practical perspective on the uncertain physical systems considered, most of the methods treated are carried out in the frequency domain. As part of the design procedure, modified Nyquist–Hall and Nichols diagrams are presented and discretized proportional–integral–derivative control schemes are reconsidered. Schemes for model-reference feedback and discrete-type observers are proposed. Although single-loop feedback systems form the core of the text, some consideration is given to multiple loops and nonlinearities. The robust control performance and stability of interval systems (with multiple uncertainties) are outlined. Finally, the monograph describes the relationship between feedback-control and discrete ev...

  14. Fractional Dynamics and Control

    CERN Document Server

    Machado, José; Luo, Albert

    2012-01-01

    Fractional Dynamics and Control provides a comprehensive overview of recent advances in the areas of nonlinear dynamics, vibration and control with analytical, numerical, and experimental results. This book provides an overview of recent discoveries in fractional control, delves into fractional variational principles and differential equations, and applies advanced techniques in fractional calculus to solving complicated mathematical and physical problems.Finally, this book also discusses the role that fractional order modeling can play in complex systems for engineering and science. Discusses how fractional dynamics and control can be used to solve nonlinear science and complexity issues Shows how fractional differential equations and models can be used to solve turbulence and wave equations in mechanics and gravity theories and Schrodinger’s equation  Presents factional relaxation modeling of dielectric materials and wave equations for dielectrics  Develops new methods for control and synchronization of...

  15. Controlling Quantum Information

    CERN Document Server

    Landahl, A J

    2002-01-01

    Quantum information science explores ways in which quantum physical laws can be harnessed to control the acquisition, transmission, protection, and processing of information. This field has seen explosive growth in the past several years from progress on both theoretical and experimental fronts. Essential to this endeavor are methods for controlling quantum information. In this thesis, I present three new approaches for controlling quantum information. First, I present a new protocol for continuously protecting unknown quantum states from noise. This protocol combines and expands ideas from the theories of quantum error correction and quantum feedback control. The result can outperform either approach by itself. I generalize this protocol to all known quantum stabilizer codes, and study its application to the three-qubit repetition code in detail via Monte Carlo simulations. Next, I present several new protocols for controlling quantum information that are fault-tolerant. These protocols require only local qu...

  16. Digital flight control systems

    Science.gov (United States)

    Caglayan, A. K.; Vanlandingham, H. F.

    1977-01-01

    The design of stable feedback control laws for sampled-data systems with variable rate sampling was investigated. These types of sampled-data systems arise naturally in digital flight control systems which use digital actuators where it is desirable to decrease the number of control computer output commands in order to save wear and tear of the associated equipment. The design of aircraft control systems which are optimally tolerant of sensor and actuator failures was also studied. Detection of the failed sensor or actuator must be resolved and if the estimate of the state is used in the control law, then it is also desirable to have an estimator which will give the optimal state estimate even under the failed conditions.

  17. Attoliter Control of Microliquid

    Science.gov (United States)

    Imura, Fumito; Kuroiwa, Hiroyuki; Nakada, Akira; Kosaka, Kouji; Kubota, Hiroshi

    2007-11-01

    The technology of the sub-femtoliter volume control of liquids in nanometer range pipettes (nanopipettes) has been developed for carrying out surgical operations on living cells. We focus attention on an interface forming between oil and water in a nanopipette. The interface position can be moved by increasing or decreasing the input pressure. If the volume of liquid in the nanopipette can be controlled by moving the position of the interface, cell organelles can be discharged or suctioned and a drug-solution can be injected into the cell. Quantity volume control in the pico-attoliter range using a tapered nanopipette is controlled by the condition of an interface with a convex shape toward the top of the nanopipette. The volume can be controlled by the input pressure corresponding to the interfacial radius without the use of a microscope by preliminarily preparing the pipette shape and the interface radius as a function of the input pressure.

  18. Structural Emergency Control Paradigm

    DEFF Research Database (Denmark)

    Vu, Thanh Long; Chatzivasileiadis, Spyros; Chiang, Hsiao-Dong

    2017-01-01

    demand and hopefully stabilize the system. This traditional emergency control results in interrupted service with severe economic damage to customers. Also, such control is usually less effective due to the lack of coordination among protective devices. In this paper, we propose a novel structural...... emergency control to render post-fault dynamics from the critical/emergency fault cleared state to the stable equilibrium point. This is a new control paradigm that does not rely on any continuous measurement or load shedding, as in the classical setup. Instead, the grid is made stable by discretely...... relocating the equilibrium point and its stability region, such that the system is consecutively attracted from the fault-cleared state back to the original equilibrium point. The proposed control is designed by solving linear and convex optimization problems, making it possibly scalable to large-scale power...

  19. Peptide identification quality control.

    Science.gov (United States)

    Vaudel, Marc; Burkhart, Julia M; Sickmann, Albert; Martens, Lennart; Zahedi, René P

    2011-05-01

    Identification of large proteomics data sets is routinely performed using sophisticated software tools called search engines. Yet despite the importance of the identification process, its configuration and execution is often performed according to established lab habits, and is mostly unsupervised by detailed quality control. In order to establish easily obtainable quality control criteria that can be broadly applied to the identification process, we here introduce several simple quality control methods. An unbiased quality control of identification parameters will be conducted using target/decoy searches providing significant improvement over identification standards. MASCOT identifications were for instance increased by 13% at a constant level of confidence. The target/decoy approach can however not be universally applied. We therefore also quality control the application of this strategy itself, providing useful and intuitive metrics for evaluating the precision and robustness of the obtained false discovery rate. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Intelligent Flow Control Valve

    Science.gov (United States)

    Kelley, Anthony R (Inventor)

    2015-01-01

    The present invention is an intelligent flow control valve which may be inserted into the flow coming out of a pipe and activated to provide a method to stop, measure, and meter flow coming from the open or possibly broken pipe. The intelligent flow control valve may be used to stop the flow while repairs are made. Once repairs have been made, the valve may be removed or used as a control valve to meter the amount of flow from inside the pipe. With the addition of instrumentation, the valve may also be used as a variable area flow meter and flow controller programmed based upon flowing conditions. With robotic additions, the valve may be configured to crawl into a desired pipe location, anchor itself, and activate flow control or metering remotely.

  1. Uncertainty and Cognitive Control

    Directory of Open Access Journals (Sweden)

    Faisal eMushtaq

    2011-10-01

    Full Text Available A growing trend of neuroimaging, behavioural and computational research has investigated the topic of outcome uncertainty in decision-making. Although evidence to date indicates that humans are very effective in learning to adapt to uncertain situations, the nature of the specific cognitive processes involved in the adaptation to uncertainty are still a matter of debate. In this article, we reviewed evidence suggesting that cognitive control processes are at the heart of uncertainty in decision-making contexts. Available evidence suggests that: (1 There is a strong conceptual overlap between the constructs of uncertainty and cognitive control; (2 There is a remarkable overlap between the neural networks associated with uncertainty and the brain networks subserving cognitive control; (3 The perception and estimation of uncertainty might play a key role in monitoring processes and the evaluation of the need for control; (4 Potential interactions between uncertainty and cognitive control might play a significant role in several affective disorders.

  2. Handbook of Chaos Control

    CERN Document Server

    Schuster, H G

    2008-01-01

    This long-awaited revised second edition of the standard reference on the subject has been considerably expanded to include such recent developments as novel control schemes, control of chaotic space-time patterns, control of noisy nonlinear systems, and communication with chaos, as well as promising new directions in research. The contributions from leading international scientists active in the field provide a comprehensive overview of our current level of knowledge on chaos control and its applications in physics, chemistry, biology, medicine, and engineering. In addition, they show the overlap with the traditional field of control theory in the engineering community.An interdisciplinary approach of interest to scientists and engineers working in a number of areas

  3. Cell Control Engineering

    DEFF Research Database (Denmark)

    Lynggaard, Hans Jørgen Birk; Alting, Leo

    1996-01-01

    The engineering process of creating cell control systems is described, and a Cell Control Engineering (CCE) concept is defined. The purpose is to assist people, representing different disciplines in the organisation, to implement cell controllers by addressing the complexity of having many systems...... in physically and logically different and changing manufacturing environments. The defined CCE concept combines state-of-the-art of commercially available enabling technologies for automation system software development, generic cell control models and guidelines for the complete engineering process....... It facilitates the understanding of the task and structure of cell controllers and uses this knowledge directly in the implementation of the system. By applying generic models CCE facilitates reuse of software components and maintenance of applications. In many enterprises, software makes up an increasing part...

  4. Controlling Electronics Boards with PVS

    CERN Multimedia

    2005-01-01

    - Introduction - Control System Architecture - Device Description - FPGA Programming - Register Control - Data Subscription - Examples of Graphics User Interfaces - Parameter - Register Translation - Application on the LHCb Timing Fast Control System

  5. CONCEPTUAL DELIMITATIONS OF CONTROLLING

    Directory of Open Access Journals (Sweden)

    Nedelcu Serban

    2011-12-01

    Full Text Available CONCEPTUAL DELIMITATIONS OF CONTROLLING Nedelcu Serban Universitatea ,,Babes-Bolyai`` Facultatea de Stiinte Economice si Gestiunea Afacerilor 'Controlling' represents a new concept in the Romanian economic environement, being implemented successfully in very few companies. Unlike the German space where controlling is very well represented both at a practical level and in the academia, in Romania controlling can only be found at a practical level, and the specialized literature is restraint, almost absent. Since the practicians of controlling in Romania only know the toolkit they use and not the theoretical elements as well, what is needed in this case is a conceptual delimitation so that controlling would be better implemented, and improved with various elements of the economic environment. In practice, inside various linguistic areas different problems of communication may occur very often in regards to the use of different concepts that may be missunderstood. Therefore in the Romanian research area it becomes imperative to try and clarify the existing issues and to intensify the reasearch in this field. Studying the evolution of the concept we observe that the need for its implementation is primarily experienced at the practical level of the companies, to be then followed by a debate in the specialized literature. The internationalization and the fierce competition that the Romanian companies are confronting on the ecenomic market represent the decissive factor in adopting the concept of controlling.This article is part of the research conducted for my doctoral thesis, 'Controlling in hetergenous economic envirnoments', under the coordination and supervision of Prof.Dr.Dumitru Matis. Keywords: Controlling, Management Accounting, Management Control, Accounting, Internal audit JEL Code: M49

  6. Common Control System Vulnerability

    Energy Technology Data Exchange (ETDEWEB)

    Trent Nelson

    2005-12-01

    The Control Systems Security Program and other programs within the Idaho National Laboratory have discovered a vulnerability common to control systems in all sectors that allows an attacker to penetrate most control systems, spoof the operator, and gain full control of targeted system elements. This vulnerability has been identified on several systems that have been evaluated at INL, and in each case a 100% success rate of completing the attack paths that lead to full system compromise was observed. Since these systems are employed in multiple critical infrastructure sectors, this vulnerability is deemed common to control systems in all sectors. Modern control systems architectures can be considered analogous to today's information networks, and as such are usually approached by attackers using a common attack methodology to penetrate deeper and deeper into the network. This approach often is composed of several phases, including gaining access to the control network, reconnaissance, profiling of vulnerabilities, launching attacks, escalating privilege, maintaining access, and obscuring or removing information that indicates that an intruder was on the system. With irrefutable proof that an external attack can lead to a compromise of a computing resource on the organization's business local area network (LAN), access to the control network is usually considered the first phase in the attack plan. Once the attacker gains access to the control network through direct connections and/or the business LAN, the second phase of reconnaissance begins with traffic analysis within the control domain. Thus, the communications between the workstations and the field device controllers can be monitored and evaluated, allowing an attacker to capture, analyze, and evaluate the commands sent among the control equipment. Through manipulation of the communication protocols of control systems (a process generally referred to as ''reverse engineering''), an

  7. Load Control System Reliability

    Energy Technology Data Exchange (ETDEWEB)

    Trudnowski, Daniel [Montana Tech of the Univ. of Montana, Butte, MT (United States)

    2015-04-03

    This report summarizes the results of the Load Control System Reliability project (DOE Award DE-FC26-06NT42750). The original grant was awarded to Montana Tech April 2006. Follow-on DOE awards and expansions to the project scope occurred August 2007, January 2009, April 2011, and April 2013. In addition to the DOE monies, the project also consisted of matching funds from the states of Montana and Wyoming. Project participants included Montana Tech; the University of Wyoming; Montana State University; NorthWestern Energy, Inc., and MSE. Research focused on two areas: real-time power-system load control methodologies; and, power-system measurement-based stability-assessment operation and control tools. The majority of effort was focused on area 2. Results from the research includes: development of fundamental power-system dynamic concepts, control schemes, and signal-processing algorithms; many papers (including two prize papers) in leading journals and conferences and leadership of IEEE activities; one patent; participation in major actual-system testing in the western North American power system; prototype power-system operation and control software installed and tested at three major North American control centers; and, the incubation of a new commercial-grade operation and control software tool. Work under this grant certainly supported the DOE-OE goals in the area of “Real Time Grid Reliability Management.”

  8. The Crane Robust Control

    Directory of Open Access Journals (Sweden)

    Marek Hicar

    2004-01-01

    Full Text Available The article is about a control design for complete structure of the crane: crab, bridge and crane uplift.The most important unknown parameters for simulations are burden weight and length of hanging rope. We will use robustcontrol for crab and bridge control to ensure adaptivity for burden weight and rope length. Robust control will be designed for current control of the crab and bridge, necessary is to know the range of unknown parameters. Whole robust will be splitto subintervals and after correct identification of unknown parameters the most suitable robust controllers will be chosen.The most important condition at the crab and bridge motion is avoiding from burden swinging in the final position. Crab and bridge drive is designed by asynchronous motor fed from frequency converter. We will use crane uplift with burden weightobserver in combination for uplift, crab and bridge drive with cooperation of their parameters: burden weight, rope length and crab and bridge position. Controllers are designed by state control method. We will use preferably a disturbance observerwhich will identify burden weight as a disturbance. The system will be working in both modes at empty hook as well asat maximum load: burden uplifting and dropping down.

  9. Fuzzy Control Teaching Models

    Directory of Open Access Journals (Sweden)

    Klaus-Dietrich Kramer

    2016-05-01

    Full Text Available Many degree courses at technical universities include the subject of control systems engineering. As an addition to conventional approaches Fuzzy Control can be used to easily find control solutions for systems, even if they include nonlinearities. To support further educational training, models which represent a technical system to be controlled are required. These models have to represent the system in a transparent and easy cognizable manner. Furthermore, a programming tool is required that supports an easy Fuzzy Control development process, including the option to verify the results and tune the system behavior. In order to support the development process a graphical user interface is needed to display the fuzzy terms under real time conditions, especially with a debug system and trace functionality. The experiences with such a programming tool, the Fuzzy Control Design Tool (FHFCE Tool, and four fuzzy teaching models will be presented in this paper. The methodical and didactical objective in the utilization of these teaching models is to develop solution strategies using Computational Intelligence (CI applications for Fuzzy Controllers in order to analyze different algorithms of inference or defuzzyfication and to verify and tune those systems efficiently.

  10. Advanced Wavefront Control Techniques

    Energy Technology Data Exchange (ETDEWEB)

    Olivier, S S; Brase, J M; Avicola, K; Thompson, C A; Kartz, M W; Winters, S; Hartley, R; Wihelmsen, J; Dowla, F V; Carrano, C J; Bauman, B J; Pennington, D M; Lande, D; Sawvel, R M; Silva, D A; Cooke, J B; Brown, C G

    2001-02-21

    Programs at LLNL that involve large laser systems--ranging from the National Ignition Facility to new tactical laser weapons--depend on the maintenance of laser beam quality through precise control of the optical wavefront. This can be accomplished using adaptive optics, which compensate for time-varying aberrations that are often caused by heating in a high-power laser system. Over the past two decades, LLNL has developed a broad capability in adaptive optics technology for both laser beam control and high-resolution imaging. This adaptive optics capability has been based on thin deformable glass mirrors with individual ceramic actuators bonded to the back. In the case of high-power lasers, these adaptive optics systems have successfully improved beam quality. However, as we continue to extend our applications requirements, the existing technology base for wavefront control cannot satisfy them. To address this issue, this project studied improved modeling tools to increase our detailed understanding of the performance of these systems, and evaluated novel approaches to low-order wavefront control that offer the possibility of reduced cost and complexity. We also investigated improved beam control technology for high-resolution wavefront control. Many high-power laser systems suffer from high-spatial-frequency aberrations that require control of hundreds or thousands of phase points to provide adequate correction. However, the cost and size of current deformable mirrors can become prohibitive for applications requiring more than a few tens of phase control points. New phase control technologies are becoming available which offer control of many phase points with small low-cost devices. The goal of this project was to expand our wavefront control capabilities with improved modeling tools, new devices that reduce system cost and complexity, and extensions to high spatial and temporal frequencies using new adaptive optics technologies. In FY 99, the second year of

  11. Cursor Control Device Characteristics

    Directory of Open Access Journals (Sweden)

    James Phillips

    2000-05-01

    Full Text Available An analysis of cursor positioning may provide guidelines for improvements in cursor control. Four experiments addressed efficiency of cursor control devices (Mouse, Digitising Pen, Accupoint, Trackball. Participants moved a cursor leftwards, upwards or rightwards, positioning it in large or small targets situated in near or far space on the computer screen. Cursor coordinates were sampled every 5 ms. The number of submovements and the proportion of time spent in deceleration were analysed. Participants could not plan movements controlled by an Accupoint. Cursor trajectories were more variable in near space for detachable manipulanda due to potential cartesian coordinate system incompatibilities

  12. Control system integration

    CERN Document Server

    Shea, T J

    2008-01-01

    This lecture begins with a definition of an accelerator control system, and then reviews the control system architectures that have been deployed at the larger accelerator facilities. This discussion naturally leads to identification of the major subsystems and their interfaces. We shall explore general strategies for integrating intelligent devices and signal processing subsystems based on gate arrays and programmable DSPs. The following topics will also be covered: physical packaging; timing and synchronization; local and global communication technologies; interfacing to machine protection systems; remote debugging; configuration management and source code control; and integration of commercial software tools. Several practical realizations will be presented.

  13. Telerik WPF controls tutorial

    CERN Document Server

    Spalding, Daniel

    2014-01-01

    Telerik Reporting is a lightweight reporting solution for all .NET cloud, web, and desktop platforms (Azure, Silverlight, WPF, ASP.NET, and Windows Forms) which targets developers and end users alike. Rich interactive and reusable reports can be created by developers in Visual Studio and by end users in the desktop-based Report Designer. This book will guide you through working with specific Telerik WPF controls as well as working with the database and other methods to load the controls. It will focus on four key technologies: the DataContext property of WPF, Telerik RadControls for WPF, XML s

  14. Asthma control in children

    DEFF Research Database (Denmark)

    Pedersen, Søren

    2016-01-01

    studies have added new information about the effects of poorly controlled asthma on a range of important, but less studied outcomes, including risk of obesity, daily physical activity, cardiovascular fitness, stress, concentration and focused attention, learning disabilities and risk of depression. From...... in whom the tests suggest good asthma control may still have poorly controlled asthma when various objective outcomes are included in the assessment. A main reason for that seems to be that none of the tests accurately detects the child's adaptation in lifestyle. If you do not exercise you have fewer...

  15. Electrostatically controlled micromechanical gyroscope

    Science.gov (United States)

    Hawkey, Timothy (Inventor); Torti, Richard (Inventor); Johnson, Bruce (Inventor)

    1994-01-01

    An integrated electrostatically-controlled micromechanical gyroscope with a rotor encompassed within a rotor cavity and electrostatically spun within the cavity. The gyroscope includes a plurality of axial electrostatic rotor actuators above and below the rotor for controlling the axial and tilt position of the rotor within the cavity, and a plurality of radial electrostatic actuators spaced circumferentially around the rotor for controlling the radial and tilt position of the rotor within the cavity. The position of the rotor within the cavity is then resolved to determine the external forces acting on the rotor.

  16. Emerging Engine Control Technologies

    DEFF Research Database (Denmark)

    Hendricks, Elbert; Chevalier, Alain

    1996-01-01

    In earlier work published by the author and co-authors, a dynamic model called a Mean Value Engine Model (MVEM) was developed. This model is physically based and is intended mainly for control applications. It is especially well suited to embedded model applications in engine controllers, susch...... as nonlinear observer based air/fuel ratio and advanced idle speed control. After a brief review of this model, it will be compared with other similar models which can be found in the literature. The attempt will be made to point out the differences between the new modified MVEM and those developed elsewhere...

  17. FABRIC QUALITY CONTROL SYSTEMS

    Directory of Open Access Journals (Sweden)

    Özlem KISAOĞLU

    2006-02-01

    Full Text Available Woven fabric quality depends on yarn properties at first, then weaving preparation and weaving processes. Defect control of grey and finished fabric is done manually on the lighted tables or automatically. Fabrics can be controlled by the help of the image analysis method. In image system the image of fabrics can be digitized by video camera and after storing controlled by the various processing. Recently neural networks, fuzzy logic, best wavelet packet model on automatic fabric inspection are developed. In this study the advantages and disadvantages of manual and automatic, on-line fabric inspection systems are given comparatively.

  18. Control rod testing apparatus

    Energy Technology Data Exchange (ETDEWEB)

    Gaunt, R.R.; Ashman, C.M.

    1987-06-02

    A control rod testing apparatus is described comprising: a first guide means having a vertical cylindrical opening for grossly guiding a control rod; a second guide means having a vertical cylindrical opening for grossly guiding a control rod. The first and second guide means are supported at axially spaced locations with the openings coaxial; and a substantially cylindrical subassembly having a vertical cylindrical opening therethrough. The subassembly is trapped coaxial with and between the first and second guide means, and the subassembly radially floats with respect to the first and second guide means.

  19. Radiological Control Manual

    Energy Technology Data Exchange (ETDEWEB)

    1993-04-01

    This manual has been prepared by Lawrence Berkeley Laboratory to provide guidance for site-specific additions, supplements, and clarifications to the DOE Radiological Control Manual. The guidance provided in this manual is based on the requirements given in Title 10 Code of Federal Regulations Part 835, Radiation Protection for Occupational Workers, DOE Order 5480.11, Radiation Protection for Occupational Workers, and the DOE Radiological Control Manual. The topics covered are (1) excellence in radiological control, (2) radiological standards, (3) conduct of radiological work, (4) radioactive materials, (5) radiological health support operations, (6) training and qualification, and (7) radiological records.

  20. Birth control pill overdose

    Science.gov (United States)

    Symptoms of an overdose of birth control pills include: Breast tenderness Discolored urine Drowsiness Heavy vaginal bleeding (2 to 7 days after the overdose) Headache Emotional changes Nausea and vomiting Rash

  1. Toxoplasmosis: Prevention and Control

    Science.gov (United States)

    ... Toxoplasmosis FAQs Toxoplasmosis & Pregnancy FAQs Epidemiology & Risk Factors Biology Disease Diagnosis Treatment Prevention & Control Resources for Health Professionals Publications Printable Resources Additional Resources Get Email Updates To receive email updates about this page, enter ...

  2. Wind Farm Control Survey

    DEFF Research Database (Denmark)

    Knudsen, Torben; Bak, Thomas; Svenstrup, Mikael

    2013-01-01

    This document is a delivery in the project NORCOWE. It is part of work package WP3.2.2. The main goal is to establish the present state-of-the-art for wind farm control for both research and practice. The main approach will be to study the literature. This will of cause be much more efficient...... for the research part than for the practice part. It is however not the intention to do company interviews or similar. This report is structured into a section for each WF control objective. These sections then includes the important control project issues: choice of input and output, control method, and modelling...... turbine farm based on a dynamic programming type of method....

  3. Fuzzy logic control

    Directory of Open Access Journals (Sweden)

    Zoltan Erdei

    2011-12-01

    Full Text Available In this paper the authors present the usefulness of fuzzy logic in controlling engineering processes or applications. Although fuzzy logic does not represent a novelty for the scientific and engineering field, it enjoys a great appreciation from those involved in the two domains. The fact that fuzzy logic uses sentences kindred with the natural language make it easier to comprehend that a complex mathematical model required by the classic control theory. In MatLab software there are dedicated toolboxes to this subject that make the design of a fuzzy controller a facile one. In the paper design methods of a fuzzy controller are being presented both in Simulink and MatLab.

  4. Control and Information Systems

    Directory of Open Access Journals (Sweden)

    Jiri Zahradnik

    2003-01-01

    Full Text Available The article deals with main tends of scientific research activities of Department of Control and Information Systems at the Faculty of Electrical Engineering of University of Zilina and its perspectives in this area.

  5. Control and Information Systems

    OpenAIRE

    Jiri Zahradnik; Karol Rastocny; Juraj Spalek

    2003-01-01

    The article deals with main tends of scientific research activities of Department of Control and Information Systems at the Faculty of Electrical Engineering of University of Zilina and its perspectives in this area.

  6. Bird control with Handcrackers

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Paper presents a new fireworks device, the Hand Cracker, from prototypes first devised by George Hockenyos (Sentinel Pest C Control Laboratory), for use in moving...

  7. Vapor Control Layer Recommendations

    Energy Technology Data Exchange (ETDEWEB)

    None

    2009-09-08

    This information sheet describes the level of vapor control required on the interior side of framed walls with typical fibrous cavity insulation (fibreglass, rockwool, or cellulose, based on DOE climate zone of construction.

  8. Locus control regions

    National Research Council Canada - National Science Library

    Li, Qiliang; Peterson, Kenneth R; Fang, Xiangdong; Stamatoyannopoulos, George

    2002-01-01

    Locus control regions (LCRs) are operationally defined by their ability to enhance the expression of linked genes to physiological levels in a tissue-specific and copy number-dependent manner at ectopic chromatin sites...

  9. Bladder Control Problems

    Science.gov (United States)

    ... urinaria puede ocurrir tanto en hombres como en mujeres. • Puede ser un problema temporal o a largo ... tercio de los hombres mayores y todas las mujeres tienen algún problema de control de la vejiga ...

  10. Active control of convection

    Energy Technology Data Exchange (ETDEWEB)

    Bau, H.H. [Univ. of Pennsylvania, Philadelphia, PA (United States)

    1995-12-31

    Using stability theory, numerical simulations, and in some instances experiments, it is demonstrated that the critical Rayleigh number for the bifurcation (1) from the no-motion (conduction) state to the motion state and (2) from time-independent convection to time-dependent, oscillatory convection in the thermal convection loop and Rayleigh-Benard problems can be significantly increased or decreased. This is accomplished through the use of a feedback controller effectuating small perturbations in the boundary data. The controller consists of sensors which detect deviations in the fluid`s temperature from the motionless, conductive values and then direct actuators to respond to these deviations in such a way as to suppress the naturally occurring flow instabilities. Actuators which modify the boundary`s temperature/heat flux are considered. The feedback controller can also be used to control flow patterns and generate complex dynamic behavior at relatively low Rayleigh numbers.

  11. Information for onchocerciasis control

    Directory of Open Access Journals (Sweden)

    Adrian Hopkins

    2010-12-01

    Full Text Available Mectizan® has been donated for the control of onchocerciasis for over twenty years, and also for the elimination of lymphatic filariasis for the last ten years. But how much is needed? I

  12. Satellite Control Laboratory

    DEFF Research Database (Denmark)

    Wisniewski, Rafal; Bak, Thomas

    2001-01-01

    The Satellite Laboratory at the Department of Control Engineering of Aalborg University (SatLab) is a dynamic motion facility designed for analysis and test of micro spacecraft. A unique feature of the laboratory is that it provides a completely gravity-free environment. A test spacecraft...... of the laboratory is to conduct dynamic tests of the control and attitude determination algorithms during nominal operation and in abnormal conditions. Further it is intended to use SatLab for validation of various algorithms for fault detection, accommodation and supervisory control. Different mission objectives...... can be implemented in the laboratory, e.g. three-axis attitude control, slew manoeuvres, spins stabilization using magnetic actuation and/or reaction wheels. The spacecraft attitude can be determined applying magnetometer measurements...

  13. Corporate Control and Underinvestment

    DEFF Research Database (Denmark)

    Poulsen, Thomas

    2013-01-01

    This paper reports a study of how the benefits that large shareholders derive from their control of a firm affect the equity issue and investment decisions of the firm. I introduce an explicit agency cost structure based on the benefits of control of the largest shareholder. In a simple extension...... of the model developed by Myers and Majluf (J Financial Econ 13:187–221, 1984), I show that underinvestment is aggravated when there are benefits of being in control and these benefits are diluted if equity is issued to finance an investment project. Using a large panel of US data, I find that the concerns...... of large shareholders about the dilution of ownership and control cause firms to issue less equity and to invest less than would otherwise be the case. I also find that it makes no significant difference whether new shares are issued to old shareholders or new shareholders....

  14. JPL Contamination Control Engineering

    Science.gov (United States)

    Blakkolb, Brian

    2013-01-01

    JPL has extensive expertise fielding contamination sensitive missions-in house and with our NASA/industry/academic partners.t Development and implementation of performance-driven cleanliness requirements for a wide range missions and payloads - UV-Vis-IR: GALEX, Dawn, Juno, WFPC-II, AIRS, TES, et al - Propulsion, thermal control, robotic sample acquisition systems. Contamination control engineering across the mission life cycle: - System and payload requirements derivation, analysis, and contamination control implementation plans - Hardware Design, Risk trades, Requirements V-V - Assembly, Integration & Test planning and implementation - Launch site operations and launch vehicle/payload integration - Flight ops center dot Personnel on staff have expertise with space materials development and flight experiments. JPL has capabilities and expertise to successfully address contamination issues presented by space and habitable environments. JPL has extensive experience fielding and managing contamination sensitive missions. Excellent working relationship with the aerospace contamination control engineering community/.

  15. Cardiovascular control during exercise

    DEFF Research Database (Denmark)

    Dela, Flemming; Mohr, Thomas; Jensen, Christina M R

    2003-01-01

    We studied the role of the central nervous system, neural feedback from contracting skeletal muscles, and sympathetic activity to the heart in the control of heart rate and blood pressure during 2 levels of dynamic exercise....

  16. Model-free control

    Science.gov (United States)

    Fliess, Michel; Join, Cédric

    2013-12-01

    'Model-free control'and the corresponding 'intelligent' PID controllers (iPIDs), which already had many successful concrete applications, are presented here for the first time in an unified manner, where the new advances are taken into account. The basics of model-free control is now employing some old functional analysis and some elementary differential algebra. The estimation techniques become quite straightforward via a recent online parameter identification approach. The importance of iPIs and especially of iPs is deduced from the presence of friction. The strange industrial ubiquity of classic PIDs and the great difficulty for tuning them in complex situations is deduced, via an elementary sampling, from their connections with iPIDs. Several numerical simulations are presented which include some infinite-dimensional systems. They demonstrate not only the power of our intelligent controllers but also the great simplicity for tuning them.

  17. Controlling Uncertain Dynamical Systems

    Indian Academy of Sciences (India)

    Author Affiliations. N Ananthkrishnan1 Rashi Bansal2. Head, CAE Analysis & Design Zeus Numerix Pvt Ltd. M-03, SINE, IIT Bombay Powai Mumbai 400076, India. MTech (Aerospace Engineering) with specialization in Dynamics & Control from IIT Bombay.

  18. MODEL PREDICTIVE CONTROL FUNDAMENTALS

    African Journals Online (AJOL)

    2012-07-02

    Jul 2, 2012 ... Discussions on some of the design techniques based on. MPC and their .... is then calculated using the receding horizon concept, since the prediction ...... of interior point methods to model predictive control,. Journal of ...

  19. Future Integrated Fire Control

    National Research Council Canada - National Science Library

    Young, Bonnie W

    2005-01-01

    Future advances in fire control for air and missile defense depend largely on a network-enabled foundation that enables the collaborative use of distributed warfare assets for time-critical operations...

  20. Controlling Cholesterol with Statins

    Science.gov (United States)

    ... For Consumers Home For Consumers Consumer Updates Controlling Cholesterol with Statins Share Tweet Linkedin Pin it More ... not, the following tips can help keep your cholesterol in check: Talk with your healthcare provider about ...