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Sample records for abnormal movement patterns

  1. Movement-related cortical potentials in paraplegic patients: abnormal patterns and considerations for BCI-rehabilitation.

    PubMed

    Xu, Ren; Jiang, Ning; Vuckovic, Aleksandra; Hasan, Muhammad; Mrachacz-Kersting, Natalie; Allan, David; Fraser, Matthew; Nasseroleslami, Bahman; Conway, Bernie; Dremstrup, Kim; Farina, Dario

    2014-01-01

    Non-invasive EEG-based Brain-Computer Interfaces (BCI) can be promising for the motor neuro-rehabilitation of paraplegic patients. However, this shall require detailed knowledge of the abnormalities in the EEG signatures of paraplegic patients. The association of abnormalities in different subgroups of patients and their relation to the sensorimotor integration are relevant for the design, implementation and use of BCI systems in patient populations. This study explores the patterns of abnormalities of movement related cortical potentials (MRCP) during motor imagery tasks of feet and right hand in patients with paraplegia (including the subgroups with/without central neuropathic pain (CNP) and complete/incomplete injury patients) and the level of distinctiveness of abnormalities in these groups using pattern classification. The most notable observed abnormalities were the amplified execution negativity and its slower rebound in the patient group. The potential underlying mechanisms behind these changes and other minor dissimilarities in patients' subgroups, as well as the relevance to BCI applications, are discussed. The findings are of interest from a neurological perspective as well as for BCI-assisted neuro-rehabilitation and therapy.

  2. [Abnormal movements. Historical notes].

    PubMed

    García-Ruiz, P J

    Most of the knowledge about movement disorders comes from the last fifty years. However, the ancients made some remarkable neurological depictions. We still can find some neurological descriptions including Parkinson's disease in the Bible, and the ancient writings of Atreya and Susruta. In addition, classic tests provide us of valuable information on historical personages, including the dystonia of Alexander the Great.

  3. Abnormal Saccadic Eye Movements in Autistic Children.

    ERIC Educational Resources Information Center

    Kemner, C.; Verbaten, M. N.; Cuperus, J. M.; Camfferman, G.; van Engeland, H.

    1998-01-01

    The saccadic eye movements, generated during a visual oddball task, were compared for 10 autistic children, 10 children with attention deficit hyperactivity disorder, 10 dyslexic children, and 10 typically developing children. Several abnormal patterns of saccades were found in the autistic group. (DB)

  4. Abnormal Movement Preparation in Task-Specific Focal Hand Dystonia

    PubMed Central

    Scheef, Lukas; Bewersdorff, Malte; Schild, Hans H.; Klockgether, Thomas; Boecker, Henning

    2013-01-01

    Electrophysiological and behavioral studies in primary dystonia suggest abnormalities during movement preparation, but this crucial phase preceding movement onset has not yet been studied specifically with functional magnetic resonance imaging (fMRI). To identify abnormalities in brain activation during movement preparation, we used event-related fMRI to analyze behaviorally unimpaired sequential finger movements in 18 patients with task-specific focal hand dystonia (FHD) and 18 healthy subjects. Patients and controls executed self-initiated or externally cued prelearnt four-digit sequential movements using either right or left hands. In FHD patients, motor performance of the sequential finger task was not associated with task-related dystonic posturing and their activation levels during motor execution were highly comparable with controls. On the other hand reduced activation was observed during movement preparation in the FHD patients in left premotor cortex / precentral gyrus for all conditions, and for self-initiation additionally in supplementary motor area, left mid-insula and anterior putamen, independent of effector side. Findings argue for abnormalities of early stages of motor control in FHD, manifesting during movement preparation. Since deficits map to regions involved in the coding of motor programs, we propose that task-specific dystonia is characterized by abnormalities during recruitment of motor programs: these do not manifest at the behavioral level during simple automated movements, however, errors in motor programs of complex movements established by extensive practice (a core feature of FHD), trigger the inappropriate movement patterns observed in task-specific dystonia. PMID:24167610

  5. Inactivation of ca10a and ca10b Genes Leads to Abnormal Embryonic Development and Alters Movement Pattern in Zebrafish

    PubMed Central

    Aspatwar, Ashok; Barker, Harlan R.; Saralahti, Anni K.; Bäuerlein, Carina A.; Ortutay, Csaba; Pan, Peiwen; Kuuslahti, Marianne; Parikka, Mataleena; Rämet, Mika; Parkkila, Seppo

    2015-01-01

    Carbonic anhydrase related proteins (CARPs) X and XI are highly conserved across species and are predominantly expressed in neural tissues. The biological role of these proteins is still an enigma. Ray-finned fish have lost the CA11 gene, but instead possess two co-orthologs of CA10. We analyzed the expression pattern of zebrafish ca10a and ca10b genes during embryonic development and in different adult tissues, and studied 61 CARP X/XI-like sequences to evaluate their phylogenetic relationship. Sequence analysis of zebrafish ca10a and ca10b reveals strongly predicted signal peptides, N-glycosylation sites, and a potential disulfide, all of which are conserved, suggesting that all of CARP X and XI are secretory proteins and potentially dimeric. RT-qPCR showed that zebrafish ca10a and ca10b genes are expressed in the brain and several other tissues throughout the development of zebrafish. Antisense morpholino mediated knockdown of ca10a and ca10b showed developmental delay with a high rate of mortality in larvae. Zebrafish morphants showed curved body, pericardial edema, and abnormalities in the head and eye, and there was increased apoptotic cell death in the brain region. Swim pattern showed abnormal movement in morphant zebrafish larvae compared to the wild type larvae. The developmental phenotypes of the ca10a and ca10b morphants were confirmed by inactivating these genes with the CRISPR/Cas9 system. In conclusion, we introduce a novel zebrafish model to investigate the mechanisms of CARP Xa and CARP Xb functions. Our data indicate that CARP Xa and CARP Xb have important roles in zebrafish development and suppression of ca10a and ca10b expression in zebrafish larvae leads to a movement disorder. PMID:26218428

  6. Complex patterns of abnormal heartbeats

    NASA Technical Reports Server (NTRS)

    Schulte-Frohlinde, Verena; Ashkenazy, Yosef; Goldberger, Ary L.; Ivanov, Plamen Ch; Costa, Madalena; Morley-Davies, Adrian; Stanley, H. Eugene; Glass, Leon

    2002-01-01

    Individuals having frequent abnormal heartbeats interspersed with normal heartbeats may be at an increased risk of sudden cardiac death. However, mechanistic understanding of such cardiac arrhythmias is limited. We present a visual and qualitative method to display statistical properties of abnormal heartbeats. We introduce dynamical "heartprints" which reveal characteristic patterns in long clinical records encompassing approximately 10(5) heartbeats and may provide information about underlying mechanisms. We test if these dynamics can be reproduced by model simulations in which abnormal heartbeats are generated (i) randomly, (ii) at a fixed time interval following a preceding normal heartbeat, or (iii) by an independent oscillator that may or may not interact with the normal heartbeat. We compare the results of these three models and test their limitations to comprehensively simulate the statistical features of selected clinical records. This work introduces methods that can be used to test mathematical models of arrhythmogenesis and to develop a new understanding of underlying electrophysiologic mechanisms of cardiac arrhythmia.

  7. Abnormal movements in children with migraine.

    PubMed

    Youssef, Paul E; Mack, Kenneth J

    2015-03-01

    The cause and treatment of functional movement disorders and nonepileptic spells in children is poorly understood, and an association with migraine has not previously been reported. We retrospectively reviewed children diagnosed with chronic or episodic migraine at our institution from 2006 to 2013 to determine the proportion with nonorganic movement disorders, their phenomenology, provoking factors, and natural history. Thirty-two patients were identified, representing 4.3% of patients with chronic migraine and 0.9% of patients with episodic migraine. Twenty-four of the 32 (75%) had chronic migraine, whereas 8 (25%) had episodic migraine. Nonepileptic spells was the most common phenomenon in both cohorts, followed by tremor and functional gait disorders. Severe migraine attacks preceded these movements in the majority of patients. With appropriate migraine therapy, significant reduction or resolution of these movements was reported. We conclude that nonorganic movement disorders are observed in pediatric migraine, are more prevalent among chronic migraineurs, and can resolve with improved pain control.

  8. Psychiatric aspects of abnormal movement disorders.

    PubMed

    Flinn, D; Bazzell, W

    1983-08-01

    It has been postulated that some movement disorders are secondary to unresolved, unconscious mental conflict; however, psychotherapeutic intervention has been unsuccessful and psychoanalytic formulations have not been shown to be valid. In addition, there is the interesting observation that some medications, stereotactic surgery and biofeedback have been successful in treating movement disorders. Moreover, as in the cases of amphetamine-induced stereotyped behavior, Parkinsonism, the acute dyskinesias, and Tardive Dyskinesia, there is evidence that some involuntary disorders of movement are biochemically mediated. Organicity, in varying degrees and involving different anatomical and physiological areas, has been observed in Tourette's Syndrome, Parkinson's disease and Huntington's disease. These diseases are usually associated with adjustment problems because of the effect that they have on the patient and the patient's family. Some of these psychosocial problems are discussed. PMID:6138131

  9. Invarient patterns in articulatory movements

    NASA Astrophysics Data System (ADS)

    Bonaventura, Patrizia

    2004-04-01

    The purpose of the reported study is to discover an effective method of characterizing movement patterns of the crucial articulator as the function of an abstract syllable magnitude and the adjacent boundary, and at the same time to investigate effects of prosodic control on utterance organization. In particular, the speed of movement when a flesh point on the tongue blade or the lower lip crosses a selected position relative to the occlusion plane is examined. The time of such crossing provides an effective measure of syllable timing and syllable duration according to previous work. In the present work, using a very limited vocabulary with only a few consonants and one vowel as the key speech materials, effects of contrastive emphasis on demisyllabic movement patterns were studied. The theoretical framework for this analysis is the C/D model of speech production in relation to the concept of an invariant part of selected articulatory movements. The results show evidence in favor of the existence of ``iceberg'' patterns, but a linear dependence of slope on the total excursion of the demisyllabic movement, instead of the approximate constancy of the threshold crossing speed as suggested in the original proposal of the iceberg, has been found. Accordingly, a revision of the original concept of iceberg, seems necessary. This refinement is consistent with the C/D model assumption on ``prominence control'' that the syllable magnitude determines the movement amplitude, accompanying directly related syllable duration change. In this assumption, the movement of a consonantal component should also be proportional to syllable magnitude. The results suggests, however, systematic outliers deviating from the linear dependence of movement speed on excursion. This deviation may be caused by the effect of the immediately following boundary, often referred to as phrase-final elongation. Thesis advisor: Osamu Fujimura Copies of this thesis written in English can be obtained from

  10. Gross Motor Development, Movement Abnormalities, and Early Identification of Autism

    ERIC Educational Resources Information Center

    Ozonoff, Sally; Young, Gregory S.; Goldring, Stacy; Greiss-Hess, Laura; Herrera, Adriana M.; Steele, Joel; Macari, Suzanne; Hepburn, Susan; Rogers, Sally J.

    2008-01-01

    Gross motor development (supine, prone, rolling, sitting, crawling, walking) and movement abnormalities were examined in the home videos of infants later diagnosed with autism (regression and no regression subgroups), developmental delays (DD), or typical development. Group differences in maturity were found for walking, prone, and supine, with…

  11. Abnormal general movements in girls with Rett disorder: the first four months of life.

    PubMed

    Einspieler, Christa; Kerr, Alison M; Prechtl, Heinz F R

    2005-11-01

    An apparently normal early development was one of the initial criteria for classical Rett syndrome. However, several investigators considered Rett syndrome to be a developmental disorder manifesting very soon after birth. Videos of 14 infants with Rett disorder were carefully assessed for their spontaneous movements, in particular general movements (GMs), during the first 4 months of life. A detailed analysis clearly demonstrated that none of the infants had normal GMs. However, a specific abnormal GM pattern could not be detected for Rett disorder. The abnormal GMs described here, and their individual developmental trajectories are different from the abnormal GMs described in infants with acquired brain lesion. Our study is the first to apply specific standardised measures of early spontaneous movements to infants with Rett syndrome, proving conclusively that the disorder is manifest within the first weeks of life.

  12. Movement and Movement Patterns of Early Childhood. [Complete Report].

    ERIC Educational Resources Information Center

    Sinclair, Caroline

    This study investigated the progressive development in movement and movement patterns of children ages 2-6. Data were collected over a 3-year period at six-month intervals, based on films of 57 children performing 25 motor tasks. The results are presented along two dimensions: (1) Descriptive analysis of progress of young children in movement with…

  13. Assessment of Specific Characteristics of Abnormal General Movements: Does It Enhance the Prediction of Cerebral Palsy?

    ERIC Educational Resources Information Center

    Hamer, Elisa G.; Bos, Arend F.; Hadders-Algra, Mijna

    2011-01-01

    Aim: Abnormal general movements at around 3 months corrected age indicate a high risk of cerebral palsy (CP). We aimed to determine whether specific movement characteristics can improve the predictive power of definitely abnormal general movements. Method: Video recordings of 46 infants with definitely abnormal general movements at 9 to 13 weeks…

  14. Subjective awareness of abnormal involuntary movements in schizophrenia.

    PubMed

    Sandyk, R; Kay, S R; Awerbuch, G I

    1993-01-01

    A wide majority of schizophrenic patients with Tardive dyskinesia, a neurological disorder produced by chronic neuroleptic therapy, lack awareness of their involuntary movements. This by contrast to patients with Parkinsonism who usually are aware of their abnormal movements. In the following communication we present a series of studies which are aimed at providing further insight into the issue of awareness of involuntary movements in schizophrenic patients with tardive dyskinesia. In addition, we investigated whether edentulosness, which may be a risk factor for orofacial dyskinesias in the elderly, is also a risk factor for neuroleptic-induced orofacial dyskinesias. We found that: (a) one's awareness of involuntary movements is related to some but not all muscle groups, (b) tardive dyskinesia may be associated with a significant distress, (c) lack of awareness may be a feature of frontal lobe dysfunction in schizophrenia, (d) patients who lack awareness of their involuntary movements have a higher prevalence of pineal calcification, and (e) edentulosness, which is related to deficits in the orofacial sensorimotor system, increases the risk for neuroleptic-induced orofacial dyskinesias. PMID:7916006

  15. Abnormal head movement in a patient with tuberculous meningitis.

    PubMed

    Garg, Ravindra Kumar; Singh, Sunil Kumar; Malhotra, Hardeep Singh; Singh, Maneesh Kumar

    2012-01-01

    The bobble-head doll syndrome is characterised by abnormal head movements. These head movements are usually 'yes-yes' (up and down) type; rarely, head movements are 'no-no' (side-to-side) type. Commonly described causes of the bobble-head doll syndrome include third ventricular tumours, suprasellar arachnoid cysts, aqueductal stenosis and other lesions in the region of the third ventricle of the brain. We report a case of tuberculous meningitis with hydrocephalus; in this patient bobble-head doll syndrome developed following external ventricular drainage. In our patient, placement of intraventricular drain led to massive dilatation of the frontal horn of the left lateral ventricle because of blocked foramina of Monro on the left side. The bobble-head doll syndrome, presumably, developed because of the pressure effect of the dilated third ventricle on the dorsomedial nucleus of the thalamus, red nucleus and dentatorubrothalamic pathways. We think that distortion of the third ventricle was responsible for the impairment of the functions of all these structures. PMID:23035162

  16. Abnormal Eye Movements in Creutzfeldt-Jakob Disease

    NASA Technical Reports Server (NTRS)

    Grant, Michael P.; Cohen, Mark; Petersen, Robert B.; Halmagyi, G. Michael; McDougall, Alan; Tusa, Ronald J.; Leigh, R. John

    1993-01-01

    We report 3 patients with autopsy-proven Creutzfeldt-Jakob disease who, early in their course, developed abnormal eye movements that included periodic alternating nystagmus and slow vertical saccades. These findings suggested involvement of the cerebellar nodulus and uvula, and the brainstem reticular formation, respectively. Cerebellar ataxia was also an early manifestation and, in one patient, a frontal lobe brain biopsy was normal at a time when ocular motor and cerebellar signs were conspicuous. As the disease progressed, all saccades and quick phases of nystagmus were lost, but periodic alternating gaze deviation persisted. At autopsy, 2 of the 3 patients had pronounced involvement of the cerebellum, especially of the midline structures. Creutzfeldt-Jakob disease should be considered in patients with subacute progressive neurological disease when cognitive changes are overshadowed by ocular motor findings or ataxia.

  17. Eye Movement Patterns of Captioned Television Viewers.

    ERIC Educational Resources Information Center

    Jensema, Carl J.; Sharkawy, Sameh El; Danturthi, Ramalinga Sarma; Burch, Robert; Hsu, David

    2000-01-01

    Eye movement of six subjects (three with deafness) was recorded as they watched video segments with and without captions. The addition of captions to a video resulted in major changes in eye movement patterns, with the viewing process becoming primarily a reading process. (Contains six references.) (Author/CR)

  18. BREATHING PATTERN DISORDERS AND FUNCTIONAL MOVEMENT

    PubMed Central

    Dr. Esformes, Joseph

    2014-01-01

    Study Design: Experimental design Background: Normal breathing mechanics play a key role in posture and spinal stabilization. Breathing Pattern Disorders (BPD) have been shown to contribute to pain and motor control deficits, which can result in dysfunctional movement patterns. The Functional Movement Screen™ (FMS™) has been shown to accurately predict injury in individuals who demonstrate poor movement patterns. The role BPD play on functional movement is not well established. Furthermore, there is currently no single test to clinically diagnose BPD. A variety of methods are used, but correlations between them are poor. Purpose: To examine the relationship between BPD and functional movement and identify correlations between different measures of BPD. Methods: Breathing was assessed in 34 healthy individuals using a multi‐dimensional approach that included biomechanical, biochemical, breathing related symptoms, and breathing functionality measures. Movement was assessed using the FMS™. Analysis, involving independent t‐tests and Pearson correlation were performed to identify associations between measures. Results: Individuals who exhibited biochemical and biomechanical signs of BPD were significantly more likely to score poorly on the FMS™. These studied measures of BPD correlated highly with each other. Conclusion: These results demonstrate the importance of diaphragmatic breathing on functional movement. Inefficient breathing could result in muscular imbalance, motor control alterations, and physiological adaptations that are capable of modifying movement. These findings provide evidence for improved breathing evaluations by clinicians. Level of Evidence: 2B PMID:24567853

  19. Patterns, Movement and Clinical Diagnosis of Abdominal Adhesions

    NASA Astrophysics Data System (ADS)

    Wright, Benjamin; Fenner, John; Gillott, Richard; Spencer, Paul; Lawford, Patricia; Bardhan, Karna Dev

    Patterns in normal abdominal movement captured with medical imaging can be recognised by a trained radiologist but the process is time consuming. Abdominal adhesions present a diagnostic problem in which the radiologist is asked to detect abnormal movement that may be indicative of pathology. This paper postulates that the use of image analysis can augment the diagnostic abilities of the radiologist in respect of adhesions. Proof of concept experiments were conducted in-silico to explore the effectiveness of the technique. The results indicate that trained participants are accurate in their assessment of abnormalities when supplied with additional information from image analysis techniques. However without the additional information, participants made incorrect diagnoses on many occasions. ROC methods were used to quantify the outcomes of the in-silico experiment.

  20. Movement Disorders and Other Motor Abnormalities in Adults With 22q11.2 Deletion Syndrome

    PubMed Central

    Boot, Erik; Butcher, Nancy J; van Amelsvoort, Thérèse AMJ; Lang, Anthony E; Marras, Connie; Pondal, Margarita; Andrade, Danielle M; Fung, Wai Lun Alan; Bassett, Anne S

    2015-01-01

    Movement abnormalities are frequently reported in children with 22q11.2 deletion syndrome (22q11.2DS), but knowledge in this area is scarce in the increasing adult population. We report on five individuals illustrative of movement disorders and other motor abnormalities in adults with 22q11.2DS. In addition to an increased susceptibility to neuropsychiatric disorders, seizures, and early-onset Parkinson disease, the underlying brain dysfunction associated with 22q11.2DS may give rise to an increased vulnerability to multiple movement abnormalities, including those influenced by medications. Movement abnormalities may also be secondary to treatable endocrine diseases and congenital musculoskeletal abnormalities. We propose that movement abnormalities may be common in adults with 22q11.2DS and discuss the implications and challenges important to clinical practice. PMID:25684639

  1. [The concept of tic in the history of abnormal movements].

    PubMed

    Dordain, G

    1986-01-01

    History of abnormal movements started during the 14th century. At that time the St Vitus' Dance was described, but the nosology of dyskinesias remained confusing during the next five centuries. The concept of tic was elaborated in France during the 18th century. It remained too large a concept however. Definitive semiologies appeared at the end of the 19th century, thus allowing tics to emerge from the "chaos of choreas". The etymology of the word "tic" still remains mysterious. In 1905, Meige thought that the word tic was used for the first time by reference to horses. He referred to the tic of the bear in the horse described by Rudler and Chomel at The Société de Neurologie de Paris in 1903. Veterinarians were thus probably the first to describe the word. If so, however, the horse must leave anteriority to the goat. The word Ticq was used in 1611 as mentioned by the French dictionary Robert. The word is said to be an onomatopea and is compared to the italian word ticchio which means caprice. Another dictionary (Littré) suggest the german word "ticken", which means "to touch slightly", the galic word tacaid (sudden pain) and the german ziki (young goat), a word which could have lead to ticchio as capra, goat in italian, gave capricio.

  2. Eye movement patterns of captioned television viewers.

    PubMed

    Jensema, C J; el Sharkawy, S; Danturthi, R S; Burch, R; Hsu, D

    2000-07-01

    Eye movement of six subjects was recorded as they watched video segments with and without captions. It was found that the addition of captions to a video resulted in major changes in eye movement patterns, with the viewing process becoming primarily a reading process. Further, although people viewing a specific video segment are likely to have similar eye movement patterns, there are also distinct individual differences present in these patterns. For example, someone accustomed to speechreading may spend more time looking at an actor's lips, while someone with poor English skills may spend more time reading the captions. Finally, there is some preliminary evidence to suggest that higher captioning speed results in more time spent reading captions on a video segment. PMID:10965591

  3. Eye movement patterns of captioned television viewers.

    PubMed

    Jensema, C J; el Sharkawy, S; Danturthi, R S; Burch, R; Hsu, D

    2000-07-01

    Eye movement of six subjects was recorded as they watched video segments with and without captions. It was found that the addition of captions to a video resulted in major changes in eye movement patterns, with the viewing process becoming primarily a reading process. Further, although people viewing a specific video segment are likely to have similar eye movement patterns, there are also distinct individual differences present in these patterns. For example, someone accustomed to speechreading may spend more time looking at an actor's lips, while someone with poor English skills may spend more time reading the captions. Finally, there is some preliminary evidence to suggest that higher captioning speed results in more time spent reading captions on a video segment.

  4. Saccadic Eye Movement Abnormalities in Children with Epilepsy.

    PubMed

    Lunn, Judith; Donovan, Tim; Litchfield, Damien; Lewis, Charlie; Davies, Robert; Crawford, Trevor

    2016-01-01

    Childhood onset epilepsy is associated with disrupted developmental integration of sensorimotor and cognitive functions that contribute to persistent neurobehavioural comorbidities. The role of epilepsy and its treatment on the development of functional integration of motor and cognitive domains is unclear. Oculomotor tasks can probe neurophysiological and neurocognitive mechanisms vulnerable to developmental disruptions by epilepsy-related factors. The study involved 26 patients and 48 typically developing children aged 8-18 years old who performed a prosaccade and an antisaccade task. Analyses compared medicated chronic epilepsy patients and unmedicated controlled epilepsy patients to healthy control children on saccade latency, accuracy and dynamics, errors and correction rate, and express saccades. Patients with medicated chronic epilepsy had impaired and more variable processing speed, reduced accuracy, increased peak velocity and a greater number of inhibitory errors, younger unmedicated patients also showed deficits in error monitoring. Deficits were related to reported behavioural problems in patients. Epilepsy factors were significant predictors of oculomotor functions. An earlier age at onset predicted reduced latency of prosaccades and increased express saccades, and the typical relationship between express saccades and inhibitory errors was absent in chronic patients, indicating a persistent reduction in tonic cortical inhibition and aberrant cortical connectivity. In contrast, onset in later childhood predicted altered antisaccade dynamics indicating disrupted neurotransmission in frontoparietal and oculomotor networks with greater demand on inhibitory control. The observed saccadic abnormalities are consistent with a dysmaturation of subcortical-cortical functional connectivity and aberrant neurotransmission. Eye movements could be used to monitor the impact of epilepsy on neurocognitive development and help assess the risk for poor neurobehavioural

  5. Saccadic Eye Movement Abnormalities in Children with Epilepsy.

    PubMed

    Lunn, Judith; Donovan, Tim; Litchfield, Damien; Lewis, Charlie; Davies, Robert; Crawford, Trevor

    2016-01-01

    Childhood onset epilepsy is associated with disrupted developmental integration of sensorimotor and cognitive functions that contribute to persistent neurobehavioural comorbidities. The role of epilepsy and its treatment on the development of functional integration of motor and cognitive domains is unclear. Oculomotor tasks can probe neurophysiological and neurocognitive mechanisms vulnerable to developmental disruptions by epilepsy-related factors. The study involved 26 patients and 48 typically developing children aged 8-18 years old who performed a prosaccade and an antisaccade task. Analyses compared medicated chronic epilepsy patients and unmedicated controlled epilepsy patients to healthy control children on saccade latency, accuracy and dynamics, errors and correction rate, and express saccades. Patients with medicated chronic epilepsy had impaired and more variable processing speed, reduced accuracy, increased peak velocity and a greater number of inhibitory errors, younger unmedicated patients also showed deficits in error monitoring. Deficits were related to reported behavioural problems in patients. Epilepsy factors were significant predictors of oculomotor functions. An earlier age at onset predicted reduced latency of prosaccades and increased express saccades, and the typical relationship between express saccades and inhibitory errors was absent in chronic patients, indicating a persistent reduction in tonic cortical inhibition and aberrant cortical connectivity. In contrast, onset in later childhood predicted altered antisaccade dynamics indicating disrupted neurotransmission in frontoparietal and oculomotor networks with greater demand on inhibitory control. The observed saccadic abnormalities are consistent with a dysmaturation of subcortical-cortical functional connectivity and aberrant neurotransmission. Eye movements could be used to monitor the impact of epilepsy on neurocognitive development and help assess the risk for poor neurobehavioural

  6. Saccadic Eye Movement Abnormalities in Children with Epilepsy

    PubMed Central

    Lunn, Judith; Donovan, Tim; Litchfield, Damien; Lewis, Charlie; Davies, Robert; Crawford, Trevor

    2016-01-01

    Childhood onset epilepsy is associated with disrupted developmental integration of sensorimotor and cognitive functions that contribute to persistent neurobehavioural comorbidities. The role of epilepsy and its treatment on the development of functional integration of motor and cognitive domains is unclear. Oculomotor tasks can probe neurophysiological and neurocognitive mechanisms vulnerable to developmental disruptions by epilepsy-related factors. The study involved 26 patients and 48 typically developing children aged 8–18 years old who performed a prosaccade and an antisaccade task. Analyses compared medicated chronic epilepsy patients and unmedicated controlled epilepsy patients to healthy control children on saccade latency, accuracy and dynamics, errors and correction rate, and express saccades. Patients with medicated chronic epilepsy had impaired and more variable processing speed, reduced accuracy, increased peak velocity and a greater number of inhibitory errors, younger unmedicated patients also showed deficits in error monitoring. Deficits were related to reported behavioural problems in patients. Epilepsy factors were significant predictors of oculomotor functions. An earlier age at onset predicted reduced latency of prosaccades and increased express saccades, and the typical relationship between express saccades and inhibitory errors was absent in chronic patients, indicating a persistent reduction in tonic cortical inhibition and aberrant cortical connectivity. In contrast, onset in later childhood predicted altered antisaccade dynamics indicating disrupted neurotransmission in frontoparietal and oculomotor networks with greater demand on inhibitory control. The observed saccadic abnormalities are consistent with a dysmaturation of subcortical-cortical functional connectivity and aberrant neurotransmission. Eye movements could be used to monitor the impact of epilepsy on neurocognitive development and help assess the risk for poor neurobehavioural

  7. Unidirectional abnormal eye movement without gaze nystagmus - Report of a case.

    PubMed

    Mizuno, Masahiro; Shibasaki, Osamu; Shindo, Susumu; Ito, Akinori; Kase, Yasuhiro

    2016-06-01

    We report here a case with unidirectional abnormalities of smooth eye movements without gaze nystagmus. Abnormalities of eye movements were confined to unidirectional (leftward) horizontal pursuit and slow phase of OKN; however, horizontal VOR (slow phase of caloric nystagmus) and saccade were normal, and vertical eye movements were also normal. No lesions were detected in the central nervous system, and any history of drug intake was denied. Although the cause of the unidirectional abnormality in eye movement of this case is still not clear, a congenital origin seems to be the most probable. PMID:26386498

  8. Cross-slope Movement Patterns in Landslides

    NASA Astrophysics Data System (ADS)

    Petley, D.; Murphy, W.; Bulmer, M. H.; Keefer, D.

    2002-12-01

    There is growing evidence that there is a significant element of cross-slope movement in many large landslide systems. These movements may result in changing states of stress between landslide blocks that can establish complex displacement patterns. Such motions, which are not considered in traditional two-dimensional limit-equilibrium analyses, are important in the investigation of a variety of landslide types, such as those triggered by earthquakes. In addition, these movements may introduce considerable errors into the interpretation of strain patterns as derived from InSAR studies. Finally, even traditional interpretation techniques may lead to the amount of total displacement being underestimated. These observations suggest that a three dimensional form of analysis may be more appropriate for large landslide complexes. The significance of such cross-slope movements are being investigated using a detailed investigation of the Lishan landslide complex in Central Taiwan. This landslide system, which was reactivated in 1990 related to the construction of a hotel. The total recorded movements have been approximately 1.5 m over an area of sliding that is estimated to be 450 m wide and 200 m long. Extensive damage has been caused to roads and buildings within the town. Remediation work has resulted largely in the stabilization of the landslide complex. Detailed geomorphological mapping has revealed that the landslide complex is composed of two main components. The first, immediately upslope of the hotel construction site, is a relatively shallow earthflow. The second, which has formed a large headscarp upslope from the main road in the centre of the town, is a deeper translational slide. Both appear to have been reactivations of previous failures. While the displacement patterns of the earthflow indicate a relatively simple downslope movement, the vectors derived from kinematic analysis of surface features have indicated that the movement of the deeper

  9. Abnormal eye movement behaviour during text reading in neglect syndrome: a case study.

    PubMed

    Karnath, H O; Huber, W

    1992-06-01

    The eye movement behaviour of a patient suffering from a right basal ganglia infarction with a left-sided hemineglect but without any visual field defects was investigated during reading. The eye movements were registered by means of an i.r. light technique (pupil-corneal reflection method). The main findings were abnormal return sweeps. Whereas in normal readers the end of one line of text is linked to the beginning of the new line by a long leftward saccade, the return sweeps of the hemineglect patient stereotypically ended in the middle of the next line. They were followed by sequences of short saccades indicating silent backward reading until a linguistically plausible continuation of sentences from the previous line was found, irrespective of the actual beginning of text. The shortened return sweeps could not be attributed to a general oculomotor disturbance. The spatial border for the occurrence of the patient's abnormal scanning pattern (left half of texts) clearly did not depend on a retinal coordinate frame of reference but rather has to be attributed to a different body-centred reference system.

  10. Abnormal Cortex-Muscle Interactions in Subjects with X-linked Kallmann's Syndrome and Mirror Movements

    ERIC Educational Resources Information Center

    Farmer, S. F.; Harrison, L. M.; Mayston, M. J.; Parekh, A.; James, L. M.; Stephens, J. A.

    2004-01-01

    X-linked Kallmann's (XKS) subjects, who display mirror movements, have abnormal corticospinal tracts which innervate motoneurons of the left and right distal muscles of the upper limb. The size of the abnormal ipsilateral projection is variable. We have used coherence and cumulant analysis between EEG and first dorsal interosseous muscle (1DI) EMG…

  11. [Abnormal adductor movement of the vocal cords in spasmodic dysphonia].

    PubMed

    Shibusawa, M

    1993-04-01

    Adductor movement of the vocal cords in initial/ke/phonation was recorded using a laryngeal fiberscope, CCD camera, and videocassette recorder. Three patients with adductor spasmodic dysphonia (SD), a 53 year old male and 48 and 52 year old females, and 7 normal volunteers participated in this study. During the examination, the subject sat on a chair holding a microphone about 20 cm away from his or her lips. A laryngeal fiberscope was inserted through either side of the nostril. The tip of the fiberscope was positioned just caudal to the tip of the epiglottis to get a complete view of both sides of the vocal cords. The examiner told the subject to make the speech sound/ke/repeatedly, and to insert a sufficient inspiratory period between each phonation. The vocal cord images were recorded at 30 frames per second and printed successively from several frames ahead of the beginning of adductor movement to the frame of initial adjustment of the membranous part of the vocal cords following a time code indicator. The tips of both sides of the vocal processes and anterior commissure were marked, then, scanned and transported to a personal computer. An imaginary line connecting the vocal process and anterior commissure was drawn on the screen of the computer, which was done on both sides of the vocal cords. Then, an angle made by the two lines was measured in degrees and stored. The time and speed of adductor movement varied among subjects. Normal subjects, however, never failed to finish making the explosive sound in /ke/ before initial vocal cord adjustment.(ABSTRACT TRUNCATED AT 250 WORDS)

  12. Dietary Patterns and Glucose Tolerance Abnormalities in Chinese Adults

    PubMed Central

    He, Yuna; Ma, Guansheng; Zhai, Fengying; Li, Yanping; Hu, Yisong; Feskens, Edith J.M.; Yang, Xiaoguang

    2009-01-01

    OBJECTIVE To investigate the association of the dietary pattern with the presence of newly diagnosed glucose tolerance abnormalities among Chinese adults. RESEARCH DESIGN AND METHODS A total of 20,210 adults aged 45–69 years from the 2002 China National Nutrition and Health Survey were included. Information on dietary intake was collected using a validated food frequency questionnaire. Factor analysis and cluster analysis were used to identify the food factors and dietary pattern clusters. RESULTS Four dietary pattern clusters were identified (“Green Water,” “Yellow Earth,” “Western Adopter,” and “New Affluence”). The prevalence of glucose tolerance abnormalities ranged from 3.9% in the Green Water to 8.0% in the New Affluence. After adjustment for area, age, sex, current smoking, and physical activity, subjects in the Yellow Earth cluster (prevalence ratio 1.22 [95% CI 1.04–1.43]) and New Affluence cluster (2.05 [1.76–2.37]) had significantly higher prevalence rates compared with those for the Green Water cluster. After further adjustment for BMI and waist-to-height ratio, the elevated risk in the New Affluence remained statistically significant. CONCLUSIONS Dietary patterns and food factors are associated with the presence of glucose tolerance abnormalities in China, even independent of obesity. A New Affluence diet is an important modifiable risk factor, which needs attention from the prevention point of view. PMID:19675202

  13. When viewing natural scenes, do abnormal colors impact on spatial or temporal parameters of eye movements?

    PubMed

    Ho-Phuoc, Tien; Guyader, Nathalie; Landragin, Frédéric; Guérin-Dugué, Anne

    2012-02-03

    Since Treisman's theory, it has been generally accepted that color is an elementary feature that guides eye movements when looking at natural scenes. Hence, most computational models of visual attention predict eye movements using color as an important visual feature. In this paper, using experimental data, we show that color does not affect where observers look when viewing natural scene images. Neither colors nor abnormal colors modify observers' fixation locations when compared to the same scenes in grayscale. In the same way, we did not find any significant difference between the scanpaths under grayscale, color, or abnormal color viewing conditions. However, we observed a decrease in fixation duration for color and abnormal color, and this was particularly true at the beginning of scene exploration. Finally, we found that abnormal color modifies saccade amplitude distribution.

  14. Hypoglycemia-induced spontaneous unilateral jerking movement in bilateral internal capsule posterior limb abnormalities.

    PubMed

    Nakajima, Nobuhito; Ueda, Masayuki; Nagayama, Hiroshi; Katayama, Yasuo

    2014-03-15

    We report an 89-year-old woman who developed consciousness disturbance associated with marked hypoglycemia, and showed involuntary movements manifested as spontaneous quick-jerking flexion followed by slow relaxation, in the right leg. Diffusion-weighted imaging revealed bilateral hyperintensities in the posterior limbs of the internal capsule (P-IC). She was treated with intravenous glucose supplementation, and her symptoms dramatically improved. The P-IC lesions are common abnormalities on MRI in hypoglycemia, and may cause paralysis. However involuntary movements associated with the lesions are rarely observed. The spontaneous jerking movements observed in this patient might result from transient impairment of the pyramidal tract associated with hypoglycemia. PMID:24411408

  15. Hierarchical patch dynamics and animal movement pattern.

    PubMed

    Fauchald, Per; Tveraa, Torkild

    2006-09-01

    In hierarchical patch systems, small-scale patches of high density are nested within large-scale patches of low density. The organization of multiple-scale hierarchical systems makes non-random strategies for dispersal and movement particularly important. Here, we apply a new method based on first-passage time on the pathway of a foraging seabird, the Antarctic petrel (Thalassoica antarctica), to quantify its foraging pattern and the spatial dynamics of its foraging areas. Our results suggest that Antarctic petrels used a nested search strategy to track a highly dynamic hierarchical patch system where small-scale patches were congregated within patches at larger scales. The birds searched for large-scale patches by traveling fast and over long distances. Once within a large-scale patch, the birds concentrated their search to find smaller scale patches. By comparing the pathway of different birds we were able to quantify the spatial scale and turnover of their foraging areas. On the largest scale we found foraging areas with a characteristic scale of about 400 km. Nested within these areas we found foraging areas with a characteristic scale of about 100 km. The large-scale areas disappeared or moved within a time frame of weeks while the nested small-scale areas disappeared or moved within days. Antarctic krill (Euphausia superba) is the dominant food item of Antarctic petrels and we suggest that our findings reflect the spatial dynamics of krill in the area. PMID:16794832

  16. Abnormal movements in first-episode, nonaffective psychosis: dyskinesias, stereotypies, and catatonic-like signs.

    PubMed

    Compton, Michael T; Fantes, Francisco; Wan, Claire Ramsay; Johnson, Stephanie; Walker, Elaine F

    2015-03-30

    Motor abnormalities represent a neurobehavioral domain of signs intrinsic to schizophrenia-spectrum disorders, though they are commonly attributed to medication side effects and remain understudied. Individuals with first-episode psychosis represent an ideal group to study innate movement disorders due to minimal prior antipsychotic exposure. We measured dyskinesias, stereotypies, and catatonic-like signs and examined their associations with: (1) age at onset of psychotic symptoms and duration of untreated psychosis; (2) positive, negative, and disorganized symptoms; (3) neurocognition; and (4) neurological soft signs. Among 47 predominantly African American first-episode psychosis patients in a public-sector hospital, the presence and severity of dyskinesias, stereotypies, and catatonic-like features were assessed using approximately 30-min video recordings. Movement abnormalities were rated utilizing three scales (Dyskinesia Identification System Condensed User Scale, Stereotypy Checklist, and Catatonia Rating Scale). Correlational analyses were conducted. Scores for each of three movement abnormality types were modestly inter-correlated (r=0.29-0.40). Stereotypy score was significantly associated with age at onset of psychotic symptoms (r=0.32) and positive symptom severity scores (r=0.29-0.41). There were no meaningful or consistent associations with negative symptom severity, neurocognition, or neurological soft signs. Abnormal movements appear to represent a relatively distinct phenotypic domain deserving of further research.

  17. Relating movement recurrence and expressive timing patterns in music performances.

    PubMed

    Teixeira, Euler C F; Yehia, Hani C; Loureiro, Mauricio A

    2015-09-01

    In this study the movement patterns of ten expert musicians are quantitatively related to expressive timing patterns and the music structure during performances. The hypothesis is that ancillary gestures recurrently employed are closely related to expressive intentions, and that the expressive content imposed in key musical passages is thus reflected in the patterns of gestural recurrence. A movement and an audio analysis of 30 clarinet performances of a Brahms' excerpt are compared. Results show direct correlations between the recurrence pattern of clarinetists' ancillary movements and expressive bar duration manipulations employed by them, associated with melodic phrasing and harmonic transitions. PMID:26428815

  18. Relating movement recurrence and expressive timing patterns in music performances.

    PubMed

    Teixeira, Euler C F; Yehia, Hani C; Loureiro, Mauricio A

    2015-09-01

    In this study the movement patterns of ten expert musicians are quantitatively related to expressive timing patterns and the music structure during performances. The hypothesis is that ancillary gestures recurrently employed are closely related to expressive intentions, and that the expressive content imposed in key musical passages is thus reflected in the patterns of gestural recurrence. A movement and an audio analysis of 30 clarinet performances of a Brahms' excerpt are compared. Results show direct correlations between the recurrence pattern of clarinetists' ancillary movements and expressive bar duration manipulations employed by them, associated with melodic phrasing and harmonic transitions.

  19. Cross-Coupled Eye Movement Supports Neural Origin of Pattern Strabismus

    PubMed Central

    Ghasia, Fatema F.; Shaikh, Aasef G.; Jacobs, Jonathan; Walker, Mark F.

    2015-01-01

    Purpose. Pattern strabismus describes vertically incomitant horizontal strabismus. Conventional theories emphasized the role of orbital etiologies, such as abnormal fundus torsion and misaligned orbital pulleys as a cause of the pattern strabismus. Experiments in animal models, however, suggested the role of abnormal cross-connections between the neural circuits. We quantitatively assessed eye movements in patients with pattern strabismus with a goal to delineate the role of neural circuits versus orbital etiologies. Methods. We measured saccadic eye movements with high-precision video-oculography in 14 subjects with pattern strabismus, 5 with comitant strabismus, and 15 healthy controls. We assessed change in eye position in the direction orthogonal to that of the desired eye movement (cross-coupled responses). We used fundus photography to quantify the fundus torsion. Results. We found cross-coupling of saccades in all patients with pattern strabismus. The cross-coupled responses were in the same direction in both eyes, but larger in the nonviewing eye. All patients had clinically apparent inferior oblique overaction with abnormal excylotorsion. There was no correlation between the amount of the fundus torsion or the grade of oblique overaction and the severity of cross-coupling. The disconjugacy in the saccade direction and amplitude in pattern strabismics did not have characteristics predicted by clinically apparent inferior oblique overaction. Conclusions. Our results validated primate models of pattern strabismus in human patients. We found no correlation between ocular torsion or oblique overaction and cross-coupling. Therefore, we could not ascribe cross-coupling exclusively to the orbital etiology. Patients with pattern strabismus could have abnormalities in the saccade generators. PMID:26024072

  20. Long-term movement patterns of a coral reef predator

    NASA Astrophysics Data System (ADS)

    Heupel, M. R.; Simpfendorfer, C. A.

    2015-06-01

    Long-term monitoring is required to fully define periodicity and patterns in animal movement. This is particularly relevant for defining what factors are driving the presence, location, and movements of individuals. The long-term movement and space use patterns of grey reef sharks, Carcharhinus amblyrhynchos, were examined on a whole of reef scale in the southern Great Barrier Reef to define whether movement and activity space varied through time. Twenty-nine C. amblyrhynchos were tracked for over 2 years to define movement patterns. All individuals showed high residency within the study site, but also had high roaming indices. This indicated that individuals remained in the region and used all of the monitored habitat (i.e., the entire reef perimeter). Use of space was consistent through time with high reuse of areas most of the year. Therefore, individuals maintained discrete home ranges, but undertook broader movements around the reef at times. Mature males showed greatest variation in movement with larger activity spaces and movement into new regions during the mating season (August-September). Depth use patterns also differed, suggesting behaviour or resource requirements varied between sexes. Examination of the long-term, reef-scale movements of C. amblyrhynchos has revealed that reproductive activity may play a key role in space use and activity patterns. It was unclear whether mating behaviour or an increased need for food to sustain reproductive activity and development played a greater role in these patterns. Reef shark movement patterns are becoming more clearly defined, but research is still required to fully understand the biological drivers for the observed patterns.

  1. TorsinA hypofunction causes abnormal twisting movements and sensorimotor circuit neurodegeneration

    PubMed Central

    Liang, Chun-Chi; Tanabe, Lauren M.; Jou, Stephanie; Chi, Frank; Dauer, William T.

    2014-01-01

    Lack of a preclinical model of primary dystonia that exhibits dystonic-like twisting movements has stymied identification of the cellular and molecular underpinnings of the disease. The classical familial form of primary dystonia is caused by the DYT1 (ΔE) mutation in TOR1A, which encodes torsinA, AAA+ ATPase resident in the lumen of the endoplasmic reticular/nuclear envelope. Here, we found that conditional deletion of Tor1a in the CNS (nestin-Cre Tor1aflox/–) or isolated CNS expression of DYT1 mutant torsinA (nestin-Cre Tor1aflox/ΔE) causes striking abnormal twisting movements. These animals developed perinuclear accumulation of ubiquitin and the E3 ubiquitin ligase HRD1 in discrete sensorimotor regions, followed by neurodegeneration that was substantially milder in nestin-Cre Tor1aflox/ΔE compared with nestin-Cre Tor1aflox/– animals. Similar to the neurodevelopmental onset of DYT1 dystonia in humans, the behavioral and histopathological abnormalities emerged and became fixed during CNS maturation in the murine models. Our results establish a genetic model of primary dystonia that is overtly symptomatic, and link torsinA hypofunction to neurodegeneration and abnormal twisting movements. These findings provide a cellular and molecular framework for how impaired torsinA function selectively disrupts neural circuits and raise the possibility that discrete foci of neurodegeneration may contribute to the pathogenesis of DYT1 dystonia. PMID:24937429

  2. Palmitoyl Serotonin Inhibits L-dopa-induced Abnormal Involuntary Movements in the Mouse Parkinson Model.

    PubMed

    Park, Hye-Yeon; Ryu, Young-Kyoung; Go, Jun; Son, Eunjung; Kim, Kyoung-Shim; Kim, Mee Ree

    2016-08-01

    L-3,4-dihydroxyphenylalanine (L-DOPA) is the most common treatment for patients with Parkinson's disease (PD). However, long term use of L-DOPA for PD therapy lead to abnormal involuntary movements (AIMs) known as dyskinesia. Fatty acid amide hydrolase (FAAH) is enriched protein in basal ganglia, and inhibition of the protein reduces dyskinetic behavior of mice. Palmitoyl serotonin (PA-5HT) is a hybrid molecule patterned after arachidonoyl serotonin, antagonist of FAAH. However, the effect of PA-5HT on L-DOPA-induced dyskinesia (LID) in PD have not yet been elucidated. To investigate whether PA-5HT relieve LID in PD and decrease hyperactivation of dopamine D1 receptors, we used the 6-hydroxydopomine (6-OHDA)-lesioned mouse model of PD and treated the L-DOPA (20 mg/kg) for 10 days with PA-5HT (0.3 mg/kg/day). The number of wall contacts with the forelimb in the cylinder test was significantly decreased by 6-OHDA lesion in mice and the pharmacotherapeutic effect of L-DOPA was also revealed in PA-5HT-treated mice. Moreover, in AIMs test, PA-5HT-treated mice showed significant reduction of locomotive, axial, limb, and orofacial AIMs score compared to the vehicle-treated mice. LID-induced hyper-phosphorylation of ERK1/2 and overexpression of FosB/ΔFosB was markedly decreased in 6-OHDA-lesioned striatum of PA-5HT-treated mice, indicating that PA-5HT decreased the dopamine D1 receptor-hyperactivation induced by chronic treatment of L-DOPA in dopamine-denervated striatum. These results suggest that PA-5HT effectively attenuates the development of LID and enhance of ERK1/2 phosphorylation and FosB/ΔFosB expression in the hemi-parkinsonian mouse model. PA-5HT may have beneficial effect on the LID in PD.

  3. Palmitoyl Serotonin Inhibits L-dopa-induced Abnormal Involuntary Movements in the Mouse Parkinson Model.

    PubMed

    Park, Hye-Yeon; Ryu, Young-Kyoung; Go, Jun; Son, Eunjung; Kim, Kyoung-Shim; Kim, Mee Ree

    2016-08-01

    L-3,4-dihydroxyphenylalanine (L-DOPA) is the most common treatment for patients with Parkinson's disease (PD). However, long term use of L-DOPA for PD therapy lead to abnormal involuntary movements (AIMs) known as dyskinesia. Fatty acid amide hydrolase (FAAH) is enriched protein in basal ganglia, and inhibition of the protein reduces dyskinetic behavior of mice. Palmitoyl serotonin (PA-5HT) is a hybrid molecule patterned after arachidonoyl serotonin, antagonist of FAAH. However, the effect of PA-5HT on L-DOPA-induced dyskinesia (LID) in PD have not yet been elucidated. To investigate whether PA-5HT relieve LID in PD and decrease hyperactivation of dopamine D1 receptors, we used the 6-hydroxydopomine (6-OHDA)-lesioned mouse model of PD and treated the L-DOPA (20 mg/kg) for 10 days with PA-5HT (0.3 mg/kg/day). The number of wall contacts with the forelimb in the cylinder test was significantly decreased by 6-OHDA lesion in mice and the pharmacotherapeutic effect of L-DOPA was also revealed in PA-5HT-treated mice. Moreover, in AIMs test, PA-5HT-treated mice showed significant reduction of locomotive, axial, limb, and orofacial AIMs score compared to the vehicle-treated mice. LID-induced hyper-phosphorylation of ERK1/2 and overexpression of FosB/ΔFosB was markedly decreased in 6-OHDA-lesioned striatum of PA-5HT-treated mice, indicating that PA-5HT decreased the dopamine D1 receptor-hyperactivation induced by chronic treatment of L-DOPA in dopamine-denervated striatum. These results suggest that PA-5HT effectively attenuates the development of LID and enhance of ERK1/2 phosphorylation and FosB/ΔFosB expression in the hemi-parkinsonian mouse model. PA-5HT may have beneficial effect on the LID in PD. PMID:27574484

  4. Palmitoyl Serotonin Inhibits L-dopa-induced Abnormal Involuntary Movements in the Mouse Parkinson Model

    PubMed Central

    Park, Hye-Yeon; Ryu, Young-Kyoung; Go, Jun; Son, Eunjung

    2016-01-01

    L-3,4-dihydroxyphenylalanine (L-DOPA) is the most common treatment for patients with Parkinson's disease (PD). However, long term use of L-DOPA for PD therapy lead to abnormal involuntary movements (AIMs) known as dyskinesia. Fatty acid amide hydrolase (FAAH) is enriched protein in basal ganglia, and inhibition of the protein reduces dyskinetic behavior of mice. Palmitoyl serotonin (PA-5HT) is a hybrid molecule patterned after arachidonoyl serotonin, antagonist of FAAH. However, the effect of PA-5HT on L-DOPA-induced dyskinesia (LID) in PD have not yet been elucidated. To investigate whether PA-5HT relieve LID in PD and decrease hyperactivation of dopamine D1 receptors, we used the 6-hydroxydopomine (6-OHDA)-lesioned mouse model of PD and treated the L-DOPA (20 mg/kg) for 10 days with PA-5HT (0.3 mg/kg/day). The number of wall contacts with the forelimb in the cylinder test was significantly decreased by 6-OHDA lesion in mice and the pharmacotherapeutic effect of L-DOPA was also revealed in PA-5HT-treated mice. Moreover, in AIMs test, PA-5HT-treated mice showed significant reduction of locomotive, axial, limb, and orofacial AIMs score compared to the vehicle-treated mice. LID-induced hyper-phosphorylation of ERK1/2 and overexpression of FosB/ΔFosB was markedly decreased in 6-OHDA-lesioned striatum of PA-5HT-treated mice, indicating that PA-5HT decreased the dopamine D1 receptor-hyperactivation induced by chronic treatment of L-DOPA in dopamine-denervated striatum. These results suggest that PA-5HT effectively attenuates the development of LID and enhance of ERK1/2 phosphorylation and FosB/ΔFosB expression in the hemi-parkinsonian mouse model. PA-5HT may have beneficial effect on the LID in PD. PMID:27574484

  5. Abnormal surface EMG during clinically normal wrist movement in cervical dystonia.

    PubMed

    de Vries, P M; Leenders, K L; van der Hoeven, J H; de Jong, B M; Kuiper, A J; Maurits, N M

    2007-11-01

    We investigated whether patients with cervical dystonia (CD) have abnormal muscle activation in non-dystonic body parts. Eight healthy controls and eight CD patients performed a flexion-extension movement of the right wrist. Movement execution was recorded by surface electromyography (EMG) from forearm muscles. Although patients had no complaints concerning wrist movement and had no apparent difficulty in executing the task, they demonstrated lower mean EMG amplitude (flexor: 0.32 mV and extensor: 0.61 mV) than controls (flexor: 0.67 mV; P = 0.021 and extensor: 1.18 mV; P = 0.068; borderline significant). Mean extensor muscle contraction was prolonged in patients (1860 ms) compared with controls (1334 ms; P = 0.026). Variation in mean EMG amplitude over movements tended to be higher in patients (flexor: 43% and extensor: 35%) than controls (flexor: 34%; P = 0.072 and extensor: 26%; P = 0.073). These results suggest that CD patients also have abnormal muscle activation in non-dystonic body parts at a subclinical level. This would support the concept that in dystonia, non-dystonic limbs are in a 'pre-dystonic state'.

  6. Neuronal substrate and effective connectivity of abnormal movement sequencing in schizophrenia.

    PubMed

    Zemankova, Petra; Lungu, Ovidiu; Huttlova, Jitka; Kerkovsky, Milos; Zubor, Jozef; Lipova, Petra; Bares, Martin; Kasparek, Tomas

    2016-06-01

    Movement sequencing difficulties are part of the neurological soft signs (NSS), they have high clinical value because they are not always present in schizophrenia. We investigated the neuronal correlates of movement sequencing in 24 healthy controls and 24 schizophrenia patients, with (SZP SQ+) or without (SZP SQ-) sequencing difficulties. We characterized simultaneous and lagged functional connectivity between brain regions involved in movement sequencing using psychophysiological interaction (PPI) and the Granger causality modeling (GCM), respectively. Left premotor cortex (PMC) and superior parietal lobule (SPL) were specifically activated during sequential movements in all participants. Right PMC and precuneus, ipsilateral to the hand executing the task, activated during sequential movements only in healthy controls and SZP SQ-. SZP SQ+ showed hyperactivation in contralateral PMC, as compared to the other groups. PPI analysis revealed a deficit in inhibitory connections within this fronto-parietal network in SZP SQ+ during sequential task. GCM showed a significant lagged effective connectivity from right PMC to left SPL during task and rest periods in all groups and from right PMC to right precuneus in SZP SQ+ group only. Both SZP groups had a significant lagged connectivity from right to left PMC, during sequential task. Our results indicate that aberrant fronto-parietal network connectivity with cortical inhibition deficit and abnormal reliance on previous network activity are related to movement sequencing in SZP. The overactivation of motor cortex seems to be a good compensating strategy, the hyperactivation of parietal cortex is linked to motor deficit symptoms. PMID:26780603

  7. Patterns of Movement in Foster Care: An Optimal Matching Analysis

    PubMed Central

    Havlicek, Judy

    2011-01-01

    Placement instability remains a vexing problem for child welfare agencies across the country. This study uses child welfare administrative data to retrospectively follow the entire placement histories (birth to age 17.5) of 474 foster youth who reached the age of majority in the state of Illinois and to search for patterns in their movement through the child welfare system. Patterns are identified through optimal matching and hierarchical cluster analyses. Multiple logistic regression is used to analyze administrative and survey data in order to examine covariates related to patterns. Five distinct patterns of movement are differentiated: Late Movers, Settled with Kin, Community Care, Institutionalized, and Early Entry. These patterns suggest high but variable rates of movement. Implications for child welfare policy and service provision are discussed. PMID:20873020

  8. Discovering loose group movement patterns from animal trajectories

    USGS Publications Warehouse

    Wang, Yuwei; Luo, Ze; Xiong, Yan; Prosser, Diann J.; Newman, Scott H.; Takekawa, John Y.; Yan, Baoping

    2015-01-01

    The technical advances of positioning technologies enable us to track animal movements at finer spatial and temporal scales, and further help to discover a variety of complex interactive relationships. In this paper, considering the loose gathering characteristics of the real-life groups' members during the movements, we propose two kinds of loose group movement patterns and corresponding discovery algorithms. Firstly, we propose the weakly consistent group movement pattern which allows the gathering of a part of the members and individual temporary leave from the whole during the movements. To tolerate the high dispersion of the group at some moments (i.e. to adapt the discontinuity of the group's gatherings), we further scheme the weakly consistent and continuous group movement pattern. The extensive experimental analysis and comparison with the real and synthetic data shows that the group pattern discovery algorithms proposed in this paper are similar to the the real-life frequent divergences of the members during the movements, can discover more complete memberships, and have considerable performance.

  9. Cluster analysis of movement patterns in multiarticular actions: a tutorial.

    PubMed

    Rein, Robert; Button, Chris; Davids, Keith; Summers, Jeffery

    2010-04-01

    The present paper proposes a technical analysis method for extracting information about movement patterning in studies of motor control, based on a cluster analysis of movement kinematics. In a tutorial fashion, data from three different experiments are presented to exemplify and validate the technical method. When applied to three different basketball-shooting techniques, the method clearly distinguished between the different patterns. When applied to a cyclical wrist supination-pronation task, the cluster analysis provided the same results as an analysis using the conventional discrete relative phase measure. Finally, when analyzing throwing performance constrained by distance to target, the method grouped movement patterns together according to throwing distance. In conclusion, the proposed technical method provides a valuable tool to improve understanding of coordination and control in different movement models, including multiarticular actions.

  10. Movement pattern recognition in basketball free-throw shooting.

    PubMed

    Schmidt, Andrea

    2012-04-01

    The purpose of the present study was to analyze the movement patterns of free-throw shooters in basketball at different skill levels. There were two points of interest. First, to explore what information can be drawn from the movement pattern and second, to examine the methodological possibilities of pattern analysis. To this end, several qualitative and quantitative methods were employed. The resulting data were converged in a triangulation. Using a special kind of ANN named Dynamically Controlled Networks (DyCoN), a 'complex feature' consisting of several isolated features (angle displacements and velocities of the articulations of the kinematic chain) was calculated. This 'complex feature' was displayed by a trajectory combining several neurons of the network, reflecting the devolution of the twelve angle measures over the time course of each shooting action. In further network analyses individual characteristics were detected, as well as movement phases. Throwing patterns were successfully classified and the stability and variability of the realized pattern were established. The movement patterns found were clearly individually shaped as well as formed by the skill level. The triangulation confirmed the individual movement organizations. Finally, a high stability of the network methods was documented.

  11. Mitochondrial abnormalities in dermatomyositis: characteristic pattern of neuropathology.

    PubMed

    Alhatou, Mohammed I; Sladky, John T; Bagasra, Omar; Glass, Jonathan D

    2004-08-01

    The objective of the work described in this paper was to evaluate mitochondrial abnormalities in perifascicular atrophic fibers in muscle biopsies from patients with dermatomyositis (DM). We localized cytochrome c oxidase (COX) and succinate dehydrogenase (SDH) histochemically in muscle biopsies of 12 patients with DM, and 12 control patients with neurogenic atrophy. These two histochemical techniques were also combined on single tissue sections in order to accentuate any COX-negative fibers. Eleven out of 12 patients (91.6%) with DM showed histochemical evidence of mitochondrial dysfunction in perifascicular distribution. Similar abnormalities in histochemical staining were not seen in comparably sized myofibers that were atrophic due to denervation. It is concluded that abnormal SDH and COX histochemical activities in atrophic perifascicular fibers are characteristic of dermatomyositis. These abnormal staining characteristics could not be accounted for solely by myofiber atrophy, or by generalized abnormalities in histochemical staining.

  12. A new method for discovering behavior patterns among animal movements

    USGS Publications Warehouse

    Wang, Y.; Luo, Ze; Takekawa, J.; Prosser, Diann J.; Xiong, Y.; Newman, S.; Xiao, X.; Batbayar, N.; Spragens, Kyle A; Balachandran, S.; Yan, B.

    2016-01-01

    Advanced satellite tracking technologies enable biologists to track animal movements at fine spatial and temporal scales. The resultant data present opportunities and challenges for understanding animal behavioral mechanisms. In this paper, we develop a new method to elucidate animal movement patterns from tracking data. Here, we propose the notion of continuous behavior patterns as a concise representation of popular migration routes and underlying sequential behaviors during migration. Each stage in the pattern is characterized in terms of space (i.e., the places traversed during movements) and time (i.e. the time spent in those places); that is, the behavioral state corresponding to a stage is inferred according to the spatiotemporal and sequential context. Hence, the pattern may be interpreted predictably. We develop a candidate generation and refinement framework to derive all continuous behavior patterns from raw trajectories. In the framework, we first define the representative spots to denote the underlying potential behavioral states that are extracted from individual trajectories according to the similarity of relaxed continuous locations in certain distinct time intervals. We determine the common behaviors of multiple individuals according to the spatiotemporal proximity of representative spots and apply a projection-based extension approach to generate candidate sequential behavior sequences as candidate patterns. Finally, the candidate generation procedure is combined with a refinement procedure to derive continuous behavior patterns. We apply an ordered processing strategy to accelerate candidate refinement. The proposed patterns and discovery framework are evaluated through conceptual experiments on both real GPS-tracking and large synthetic datasets.

  13. A new method for discovering behavior patterns among animal movements

    PubMed Central

    Wang, Yuwei; Luo, Ze; Takekawa, John; Prosser, Diann; Xiong, Yan; Newman, Scott; Xiao, Xiangming; Batbayar, Nyambayar; Spragens, Kyle; Balachandran, Sivananinthaperumal; Yan, Baoping

    2016-01-01

    Advanced satellite tracking technologies enable biologists to track animal movements at fine spatial and temporal scales. The resultant data present opportunities and challenges for understanding animal behavioral mechanisms. In this paper, we develop a new method to elucidate animal movement patterns from tracking data. Here, we propose the notion of continuous behavior patterns as a concise representation of popular migration routes and underlying sequential behaviors during migration. Each stage in the pattern is characterized in terms of space (i.e., the places traversed during movements) and time (i.e. the time spent in those places); that is, the behavioral state corresponding to a stage is inferred according to the spatiotemporal and sequential context. Hence, the pattern may be interpreted predictably. We develop a candidate generation and refinement framework to derive all continuous behavior patterns from raw trajectories. In the framework, we first define the representative spots to denote the underlying potential behavioral states that are extracted from individual trajectories according to the similarity of relaxed continuous locations in certain distinct time intervals. We determine the common behaviors of multiple individuals according to the spatiotemporal proximity of representative spots and apply a projection-based extension approach to generate candidate sequential behavior sequences as candidate patterns. Finally, the candidate generation procedure is combined with a refinement procedure to derive continuous behavior patterns. We apply an ordered processing strategy to accelerate candidate refinement. The proposed patterns and discovery framework are evaluated through conceptual experiments on both real GPS-tracking and large synthetic datasets. PMID:27217810

  14. Understanding the spatiotemporal pattern of grazing cattle movement

    PubMed Central

    Zhao, Kun; Jurdak, Raja

    2016-01-01

    Understanding the drivers of animal movement is significant for ecology and biology. Yet researchers have so far been unable to fully understand these drivers, largely due to low data resolution. In this study, we analyse a high-frequency movement dataset for a group of grazing cattle and investigate their spatiotemporal patterns using a simple two-state ‘stop-and-move’ mobility model. We find that the dispersal kernel in the moving state is best described by a mixture exponential distribution, indicating the hierarchical nature of the movement. On the other hand, the waiting time appears to be scale-invariant below a certain cut-off and is best described by a truncated power-law distribution, suggesting that the non-moving state is governed by time-varying dynamics. We explore possible explanations for the observed phenomena, covering factors that can play a role in the generation of mobility patterns, such as the context of grazing environment, the intrinsic decision-making mechanism or the energy status of different activities. In particular, we propose a new hypothesis that the underlying movement pattern can be attributed to the most probable observable energy status under the maximum entropy configuration. These results are not only valuable for modelling cattle movement but also provide new insights for understanding the underlying biological basis of grazing behaviour. PMID:27555220

  15. Understanding the spatiotemporal pattern of grazing cattle movement.

    PubMed

    Zhao, Kun; Jurdak, Raja

    2016-01-01

    Understanding the drivers of animal movement is significant for ecology and biology. Yet researchers have so far been unable to fully understand these drivers, largely due to low data resolution. In this study, we analyse a high-frequency movement dataset for a group of grazing cattle and investigate their spatiotemporal patterns using a simple two-state 'stop-and-move' mobility model. We find that the dispersal kernel in the moving state is best described by a mixture exponential distribution, indicating the hierarchical nature of the movement. On the other hand, the waiting time appears to be scale-invariant below a certain cut-off and is best described by a truncated power-law distribution, suggesting that the non-moving state is governed by time-varying dynamics. We explore possible explanations for the observed phenomena, covering factors that can play a role in the generation of mobility patterns, such as the context of grazing environment, the intrinsic decision-making mechanism or the energy status of different activities. In particular, we propose a new hypothesis that the underlying movement pattern can be attributed to the most probable observable energy status under the maximum entropy configuration. These results are not only valuable for modelling cattle movement but also provide new insights for understanding the underlying biological basis of grazing behaviour. PMID:27555220

  16. Restoration of movement patterns of the Hawaiian Goose

    USGS Publications Warehouse

    Hess, Steven C.; Leopold, Christina R.; Misajon, Kathleen; Hu, Darcy; Jeffrey, John J.

    2012-01-01

    We used visual observations of banded individuals and satellite telemetry from 2007 to 2011 on Hawai′i Island to document movement patterns of the Hawaiian Goose (Branta sandvicensis), commonly known as Nene. Visual observations of numbered leg bands identified >19% and ≤10% of 323 geese at one of two breeding sites and one of two distant non-breeding areas during 2007-2011. We used satellite telemetry to document movement patterns of 10 male Nene from 2009 to 2011, and log-linear models to quantify the magnitude and individual differences in altitudinal migration. Two subpopulations of Nene moved 974.4 m (95% CI ± 22.0) and 226.4 m (95% CI ± 40.7) in elevation between seasons on average, from high-elevation shrublands during the non-breeding season of May-August, to lower-elevation breeding and molting areas in September-April. Traditional movement patterns were thought to be lost until recently, but the movement pattern we documented with satellite telemetry was similar to altitudinal migration described by early naturalists in Hawai′i prior to the severe population decline of Nene in the 20th century.

  17. Seasonal and Ontogenetic Changes in Movement Patterns of Sixgill Sharks

    PubMed Central

    Andrews, Kelly S.; Williams, Greg D.; Levin, Phillip S.

    2010-01-01

    Background Understanding movement patterns is fundamental to population and conservation biology. The way an animal moves through its environment influences the dynamics of local populations and will determine how susceptible it is to natural or anthropogenic perturbations. It is of particular interest to understand the patterns of movement for species which are susceptible to human activities (e.g. fishing), or that exert a large influence on community structure, such as sharks. Methodology/Principal Findings We monitored the patterns of movement of 34 sixgill sharks Hexanchus griseus using two large-scale acoustic arrays inside and outside Puget Sound, Washington, USA. Sixgill sharks were residents in Puget Sound for up to at least four years before making large movements out of the estuary. Within Puget Sound, sixgills inhabited sites for several weeks at a time and returned to the same sites annually. Across four years, sixgills had consistent seasonal movements in which they moved to the north from winter to spring and moved to the south from summer to fall. Just prior to leaving Puget Sound, sixgills altered their behavior and moved twice as fast among sites. Nineteen of the thirty-four sixgills were detected leaving Puget Sound for the outer coast. Three of these sharks returned to Puget Sound. Conclusions/Significance For most large marine predators, we have a limited understanding of how they move through their environment, and this clouds our ability to successfully manage their populations and their communities. With detailed movement information, such as that being uncovered with acoustic monitoring, we can begin to quantify the spatial and temporal impacts of large predators within the framework of their ecosystems. PMID:20838617

  18. Fatigue in multiple sclerosis is associated with abnormal cortical activation to voluntary movement--EEG evidence.

    PubMed

    Leocani, L; Colombo, B; Magnani, G; Martinelli-Boneschi, F; Cursi, M; Rossi, P; Martinelli, V; Comi, G

    2001-06-01

    Converging evidence is consistent with the view that fatigue in Multiple Sclerosis is independent from pyramidal tract involvement, suggesting a possible involvement of frontal areas. During voluntary movement, changes of the EEG rhythms can be observed over sensorimotor areas. Event-related desynchronization (ERD) of the 10 and 20 Hz frequency bands occurs during motor planning and execution and is followed after movement termination by event-related synchronization (ERS), expressing cortical idling or inhibition. We evaluated the pattern of cortical activation to voluntary movement in MS patients complaining of fatigue assessed using the Fatigue Severity Scale. Fifteen MS patients complaining of fatigue, 18 MS patients without fatigue, and 14 normal controls were studied. The two patients groups were similar for age, sex, disease duration, and were not disabled (score <1.5 at the Expanded Disability Status Scale). Twenty-nine channel EEG was recorded during about 60 self-paced extensions of the right thumb. The onset latency and amount of the contralateral sensorimotor (C3 electrode) 10 and 18--22 Hz ERD were similar in the three groups. ERD was more widespread anteriorly in the fatigue group compared with normal controls (P < 0.01 over Fz electrode). Postmovement contralateral sensorimotor 18--22 Hz ERS was significantly lower in fatigue MS patients compared with normal subjects (P < 0.005) and with nonfatigue MS patients (P = 0.02). These findings are consistent with a central origin of fatigue in MS and indicate cortical dysfunction even during a simple motor task, resulting in hyperactivity during movement execution and failure of the inhibitory mechanisms intervening after movement termination. PMID:11352624

  19. Mining Spatiotemporal Patterns of the Elder's Daily Movement

    NASA Astrophysics Data System (ADS)

    Chen, C. R.; Chen, C. F.; Liu, M. E.; Tsai, S. J.; Son, N. T.; Kinh, L. V.

    2016-06-01

    With rapid developments in wearable device technology, a vast amount of spatiotemporal data, such as people's movement and physical activities, are generated. Information derived from the data reveals important knowledge that can contribute a long-term care and psychological assessment of the elders' living condition especially in long-term care institutions. This study aims to develop a method to investigate the spatial-temporal movement patterns of the elders with their outdoor trajectory information. To achieve the goal, GPS based location data of the elderly subjects from long-term care institutions are collected and analysed with geographic information system (GIS). A GIS statistical model is developed to mine the elderly subjects' spatiotemporal patterns with the location data and represent their daily movement pattern at particular time. The proposed method first finds the meaningful trajectory and extracts the frequent patterns from the time-stamp location data. Then, a density-based clustering method is used to identify the major moving range and the gather/stay hotspot in both spatial and temporal dimensions. The preliminary results indicate that the major moving area of the elderly people encompasses their dorm and has a short moving distance who often stay in the same site. Subjects' outdoor appearance are corresponded to their life routine. The results can be useful for understanding elders' social network construction, risky area identification and medical care monitoring.

  20. Noise Effects on the Complex Patterns of Abnormal Heartbeats

    SciTech Connect

    Schulte-Frohlinde, Verena; Ashkenazy, Yosef; Ivanov, Plamen Ch.; Glass, Leon; Goldberger, Ary L.; Stanley, H. Eugene

    2001-08-06

    Patients at high risk for sudden death often exhibit complex heart rhythms in which abnormal heartbeats are interspersed with normal heartbeats. We analyze such a complex rhythm in a single patient over a 12-h period and show that the rhythm can be described by a theoretical model consisting of two interacting oscillators with stochastic elements. By varying the magnitude of the noise, we show that for an intermediate level of noise, the model gives best agreement with key statistical features of the dynamics.

  1. Noise effects on the complex patterns of abnormal heartbeats

    NASA Technical Reports Server (NTRS)

    Schulte-Frohlinde, V.; Ashkenazy, Y.; Ivanov, P. C.; Glass, L.; Goldberger, A. L.; Stanley, H. E.

    2001-01-01

    Patients at high risk for sudden death often exhibit complex heart rhythms in which abnormal heartbeats are interspersed with normal heartbeats. We analyze such a complex rhythm in a single patient over a 12-h period and show that the rhythm can be described by a theoretical model consisting of two interacting oscillators with stochastic elements. By varying the magnitude of the noise, we show that for an intermediate level of noise, the model gives best agreement with key statistical features of the dynamics.

  2. Patterns of Structural MRI Abnormalities in Deficit and Nondeficit Schizophrenia

    PubMed Central

    Galderisi, Silvana; Quarantelli, Mario; Volpe, Umberto; Mucci, Armida; Cassano, Giovanni Battista; Invernizzi, Giordano; Rossi, Alessandro; Vita, Antonio; Pini, Stefano; Cassano, Paolo; Daneluzzo, Enrico; De Peri, Luca; Stratta, Paolo; Brunetti, Arturo; Maj, Mario

    2008-01-01

    Negative symptoms of schizophrenia have generally been found in association with ventricular enlargement and prefrontal abnormalities. These relationships, however, have not been observed consistently, most probably because negative symptoms are heterogeneous and result from different pathophysiological mechanisms. The concept of deficit schizophrenia (DS) was introduced by Carpenter et al to identify a clinically homogeneous subgroup of patients characterized by the presence of primary and enduring negative symptoms. Findings of brain structural abnormalities reported by magnetic resonance imaging (MRI) studies focusing on DS have been mixed. The present study included 34 patients with DS, 32 with nondeficit schizophrenia (NDS), and 31 healthy comparison subjects, providing the largest set of MRI findings in DS published so far. The Schedule for the Deficit Syndrome was used to categorize patients as DS or NDS patients. The 2 patient groups were matched on age and gender and did not differ on clinical variables, except for higher scores on the negative dimension and more impaired interpersonal relationships in DS than in NDS subjects. Lateral ventricles were larger in NDS than in control subjects but were not enlarged in patients with DS. The cingulate gyri volume was smaller in NDS but not in DS patients as compared with healthy subjects. Both groups had smaller dorsolateral prefrontal cortex and temporal lobes than healthy subjects, but DS patients had significantly less right temporal lobe volume as compared with NDS patients. These findings do not support the hypothesis that DS is the extreme end of a severity continuum within schizophrenia. PMID:17728266

  3. Optimizing Detection Rate and Characterization of Subtle Paroxysmal Neonatal Abnormal Facial Movements with Multi-Camera Video-Electroencephalogram Recordings.

    PubMed

    Pisani, Francesco; Pavlidis, Elena; Cattani, Luca; Ferrari, Gianluigi; Raheli, Riccardo; Spagnoli, Carlotta

    2016-06-01

    Objectives We retrospectively analyze the diagnostic accuracy for paroxysmal abnormal facial movements, comparing one camera versus multi-camera approach. Background Polygraphic video-electroencephalogram (vEEG) recording is the current gold standard for brain monitoring in high-risk newborns, especially when neonatal seizures are suspected. One camera synchronized with the EEG is commonly used. Methods Since mid-June 2012, we have started using multiple cameras, one of which point toward newborns' faces. We evaluated vEEGs recorded in newborns in the study period between mid-June 2012 and the end of September 2014 and compared, for each recording, the diagnostic accuracies obtained with one-camera and multi-camera approaches. Results We recorded 147 vEEGs from 87 newborns and found 73 episodes of paroxysmal facial abnormal movements in 18 vEEGs of 11 newborns with the multi-camera approach. By using the single-camera approach, only 28.8% of these events were identified (21/73). Ten positive vEEGs with multicamera with 52 paroxysmal facial abnormal movements (52/73, 71.2%) would have been considered as negative with the single-camera approach. Conclusions The use of one additional facial camera can significantly increase the diagnostic accuracy of vEEGs in the detection of paroxysmal abnormal facial movements in the newborns.

  4. Movement patterns of silvertip sharks ( Carcharhinus albimarginatus) on coral reefs

    NASA Astrophysics Data System (ADS)

    Espinoza, Mario; Heupel, Michelle. R.; Tobin, Andrew J.; Simpfendorfer, Colin A.

    2015-09-01

    Understanding how sharks use coral reefs is essential for assessing risk of exposure to fisheries, habitat loss, and climate change. Despite a wide Indo-Pacific distribution, little is known about the spatial ecology of silvertip sharks ( Carcharhinus albimarginatus), compromising the ability to effectively manage their populations. We examined the residency and movements of silvertip sharks in the central Great Barrier Reef (GBR). An array of 56 VR2W acoustic receivers was used to monitor shark movements on 17 semi-isolated reefs. Twenty-seven individuals tagged with acoustic transmitters were monitored from 70 to 731 d. Residency index to the study site ranged from 0.05 to 0.97, with a mean residency (±SD) of 0.57 ± 0.26, but most individuals were detected at or near their tagging reef. Clear seasonal patterns were apparent, with fewer individuals detected between September and February. A large proportion of the tagged population (>71 %) moved regularly between reefs. Silvertip sharks were detected less during daytime and exhibited a strong diel pattern in depth use, which may be a strategy for optimizing energetic budgets and foraging opportunities. This study provides the first detailed examination of the spatial ecology and behavior of silvertip sharks on coral reefs. Silvertip sharks remained resident at coral reef habitats over long periods, but our results also suggest this species may have more complex movement patterns and use larger areas of the GBR than common reef shark species. Our findings highlight the need to further understand the movement ecology of silvertip sharks at different spatial and temporal scales, which is critical for developing effective management approaches.

  5. A New Qualitative Typology to Classify Treading Water Movement Patterns

    PubMed Central

    Schnitzler, Christophe; Button, Chris; Croft, James L.

    2015-01-01

    This study proposes a new qualitative typology that can be used to classify learners treading water into different skill-based categories. To establish the typology, 38 participants were videotaped while treading water and their movement patterns were qualitatively analyzed by two experienced biomechanists. 13 sport science students were then asked to classify eight of the original participants after watching a brief tutorial video about how to use the typology. To examine intra-rater consistency, each participant was presented in a random order three times. Generalizability (G) and Decision (D) studies were performed to estimate the importance variance due to rater, occasion, video and the interactions between them, and to determine the reliability of the raters’ answers. A typology of five general classes of coordination was defined amongst the original 38 participants. The G-study showed an accurate and reliable assessment of different pattern type, with a percentage of correct classification of 80.1%, an overall Fleiss’ Kappa coefficient K = 0.6, and an overall generalizability φ coefficient of 0.99. This study showed that the new typology proposed to characterize the behaviour of individuals treading water was both accurate and highly reliable. Movement pattern classification using the typology might help practitioners distinguish between different skill-based behaviours and potentially guide instruction of key aquatic survival skills. Key points Treading water behavioral adaptation can be classified along two dimensions: the type of force created (drag vs lift), and the frequency of the force impulses Based on these concepts, 9 behavioral types can be identified, providing the basis for a typology Provided with macroscopic descriptors (movements of the limb relative to the water, and synchronous vs asynchronous movements), analysts can characterize behavioral type accurately and reliably. PMID:26336339

  6. Wheelchair propulsion efficiency: movement pattern adaptations to speed changes.

    PubMed

    Vanlandewijck, Y C; Spaepen, A J; Lysens, R J

    1994-11-01

    Low mechanical efficiency values in wheelchair propulsion are usually explained on the basis of the supply of force and power generated during the push phase. The purpose of this study is to analyze the movement and muscular activity pattern in handrim wheelchair propulsion, focusing on both the push and recovery phases. Data on cardiorespiratory and propulsion technique parameters were obtained from 40 wheelchair basketball players with extensive experience in wheelchair propulsion in six situations: two exercise levels (60% and 80% of individual VO2peak), and three velocities (1.11, 1.67, and 2.22 m.s-1) with constant power output on a treadmill. A two-factor analysis of variance with repeated measurements was applied with "exercise level" and "speed" as the main factors. A significant effect on gross mechanical efficiency was found when the velocity was increased from 1.67 to 2.22 m.s-1. Decreased mechanical efficiency could be explained by a significant change in the acceleration of the wheelchair-user system during recovery, caused by arm and trunk movements, inducing inertial forces to act on the wheelchair. Consequently, mechanical work increased significantly during the recovery phase. These findings indicate that studies on mechanical efficiency in wheelchair propulsion should not only be focussed on power supply during the push phase, but also on the movement pattern during recovery.

  7. Synergistic combination of clinical and imaging features predicts abnormal imaging patterns of pulmonary infections

    PubMed Central

    Bagci, Ulas; Jaster-Miller, Kirsten; Olivier, Kenneth N.; Yao, Jianhua; Mollura, Daniel J.

    2013-01-01

    We designed and tested a novel hybrid statistical model that accepts radiologic image features and clinical variables, and integrates this information in order to automatically predict abnormalities in chest computed-tomography (CT) scans and identify potentially important infectious disease biomarkers. In 200 patients, 160 with various pulmonary infections and 40 healthy controls, we extracted 34 clinical variables from laboratory tests and 25 textural features from CT images. From the CT scans, pleural effusion (PE), linear opacity (or thickening) (LT), tree-in-bud (TIB), pulmonary nodules, ground glass opacity (GGO), and consolidation abnormality patterns were analyzed and predicted through clinical, textural (imaging), or combined attributes. The presence and severity of each abnormality pattern was validated by visual analysis of the CT scans. The proposed biomarker identification system included two important steps: (i) a coarse identification of an abnormal imaging pattern by adaptively selected features (AmRMR), and (ii) a fine selection of the most important features from the previous step, and assigning them as biomarkers, depending on the prediction accuracy. Selected biomarkers were used to classify normal and abnormal patterns by using a boosted decision tree (BDT) classifier. For all abnormal imaging patterns, an average prediction accuracy of 76.15% was obtained. Experimental results demonstrated that our proposed biomarker identification approach is promising and may advance the data processing in clinical pulmonary infection research and diagnostic techniques. PMID:23930819

  8. Tongue-surface movement patterns during speech and swallowing.

    PubMed

    Green, Jordan R; Wang, Yu-Tsai

    2003-05-01

    The tongue has been frequently characterized as being composed of several functionally independent articulators. The question of functional regionality within the tongue was examined by quantifying the strength of coupling among four different tongue locations across a large number of consonantal contexts and participants. Tongue behavior during swallowing was also described. Vertical displacements of pellets affixed to the tongue were extracted from the x-ray microbeam database. Forty-six participants recited 20 vowel-consonant-vowel (VCV) combinations and swallowed 10 ccs of water. Tongue-surface movement patterns were quantitatively described by computing the covariance between the vertical time-histories of all possible pellet pairs. Phonemic differentiation in vertical tongue motions was observed as coupling varied predictably across pellet pairs with place of articulation. Moreover, tongue displacements for speech and swallowing clustered into distinct groups based on their coupling profiles. Functional independence of anterior tongue regions was evidenced by a wide range of movement coupling relations between anterior tongue pellets. The strengths and weaknesses of the covariance-based analysis for characterizing tongue movement are considered.

  9. Pattern recognition of abnormal left ventricle wall motion in cardiac MR.

    PubMed

    Lu, Yingli; Radau, Perry; Connelly, Kim; Dick, Alexander; Wright, Graham

    2009-01-01

    There are four main problems that limit application of pattern recognition techniques for recognition of abnormal cardiac left ventricle (LV) wall motion: (1) Normalization of the LV's size, shape, intensity level and position; (2) defining a spatial correspondence between phases and subjects; (3) extracting features; (4) and discriminating abnormal from normal wall motion. Solving these four problems is required for application of pattern recognition techniques to classify the normal and abnormal LV wall motion. In this work, we introduce a normalization scheme to solve the first and second problems. With this scheme, LVs are normalized to the same position, size, and intensity level. Using the normalized images, we proposed an intra-segment classification criterion based on a correlation measure to solve the third and fourth problems. Application of the method to recognition of abnormal cardiac MR LV wall motion showed promising results.

  10. Processing Rhythmic Pattern during Chinese Sentence Reading: An Eye Movement Study.

    PubMed

    Luo, Yingyi; Duan, Yunyan; Zhou, Xiaolin

    2015-01-01

    Prosodic constraints play a fundamental role during both spoken sentence comprehension and silent reading. In Chinese, the rhythmic pattern of the verb-object (V-O) combination has been found to rapidly affect the semantic access/integration process during sentence reading (Luo and Zhou, 2010). Rhythmic pattern refers to the combination of words with different syllabic lengths, with certain combinations disallowed (e.g., [2 + 1]; numbers standing for the number of syllables of the verb and the noun respectively) and certain combinations preferred (e.g., [1 + 1] or [2 + 2]). This constraint extends to the situation in which the combination is used to modify other words. A V-O phrase could modify a noun by simply preceding it, forming a V-O-N compound; when the verb is disyllabic, however, the word order has to be O-V-N and the object is preferred to be disyllabic. In this study, we investigated how the reader processes the rhythmic pattern and word order information by recording the reader's eye-movements. We created four types of sentences by crossing rhythmic pattern and word order in compounding. The compound, embedding a disyllabic verb, could be in the correct O-V-N or the incorrect V-O-N order; the object could be disyllabic or monosyllabic. We found that the reader spent more time and made more regressions on and after the compounds when either type of anomaly was detected during the first pass reading. However, during re-reading (after all the words in the sentence have been viewed), less regressive eye movements were found for the anomalous rhythmic pattern, relative to the correct pattern; moreover, only the abnormal rhythmic pattern, not the violated word order, influenced the regressive eye movements. These results suggest that while the processing of rhythmic pattern and word order information occurs rapidly during the initial reading of the sentence, the process of recovering from the rhythmic pattern anomaly may ease the reanalysis processing at the

  11. Processing Rhythmic Pattern during Chinese Sentence Reading: An Eye Movement Study

    PubMed Central

    Luo, Yingyi; Duan, Yunyan; Zhou, Xiaolin

    2015-01-01

    Prosodic constraints play a fundamental role during both spoken sentence comprehension and silent reading. In Chinese, the rhythmic pattern of the verb-object (V-O) combination has been found to rapidly affect the semantic access/integration process during sentence reading (Luo and Zhou, 2010). Rhythmic pattern refers to the combination of words with different syllabic lengths, with certain combinations disallowed (e.g., [2 + 1]; numbers standing for the number of syllables of the verb and the noun respectively) and certain combinations preferred (e.g., [1 + 1] or [2 + 2]). This constraint extends to the situation in which the combination is used to modify other words. A V-O phrase could modify a noun by simply preceding it, forming a V-O-N compound; when the verb is disyllabic, however, the word order has to be O-V-N and the object is preferred to be disyllabic. In this study, we investigated how the reader processes the rhythmic pattern and word order information by recording the reader's eye-movements. We created four types of sentences by crossing rhythmic pattern and word order in compounding. The compound, embedding a disyllabic verb, could be in the correct O-V-N or the incorrect V-O-N order; the object could be disyllabic or monosyllabic. We found that the reader spent more time and made more regressions on and after the compounds when either type of anomaly was detected during the first pass reading. However, during re-reading (after all the words in the sentence have been viewed), less regressive eye movements were found for the anomalous rhythmic pattern, relative to the correct pattern; moreover, only the abnormal rhythmic pattern, not the violated word order, influenced the regressive eye movements. These results suggest that while the processing of rhythmic pattern and word order information occurs rapidly during the initial reading of the sentence, the process of recovering from the rhythmic pattern anomaly may ease the reanalysis processing at the

  12. Processing Rhythmic Pattern during Chinese Sentence Reading: An Eye Movement Study.

    PubMed

    Luo, Yingyi; Duan, Yunyan; Zhou, Xiaolin

    2015-01-01

    Prosodic constraints play a fundamental role during both spoken sentence comprehension and silent reading. In Chinese, the rhythmic pattern of the verb-object (V-O) combination has been found to rapidly affect the semantic access/integration process during sentence reading (Luo and Zhou, 2010). Rhythmic pattern refers to the combination of words with different syllabic lengths, with certain combinations disallowed (e.g., [2 + 1]; numbers standing for the number of syllables of the verb and the noun respectively) and certain combinations preferred (e.g., [1 + 1] or [2 + 2]). This constraint extends to the situation in which the combination is used to modify other words. A V-O phrase could modify a noun by simply preceding it, forming a V-O-N compound; when the verb is disyllabic, however, the word order has to be O-V-N and the object is preferred to be disyllabic. In this study, we investigated how the reader processes the rhythmic pattern and word order information by recording the reader's eye-movements. We created four types of sentences by crossing rhythmic pattern and word order in compounding. The compound, embedding a disyllabic verb, could be in the correct O-V-N or the incorrect V-O-N order; the object could be disyllabic or monosyllabic. We found that the reader spent more time and made more regressions on and after the compounds when either type of anomaly was detected during the first pass reading. However, during re-reading (after all the words in the sentence have been viewed), less regressive eye movements were found for the anomalous rhythmic pattern, relative to the correct pattern; moreover, only the abnormal rhythmic pattern, not the violated word order, influenced the regressive eye movements. These results suggest that while the processing of rhythmic pattern and word order information occurs rapidly during the initial reading of the sentence, the process of recovering from the rhythmic pattern anomaly may ease the reanalysis processing at the

  13. Eye Movement and Visual Search: Are There Elementary Abnormalities in Autism?

    ERIC Educational Resources Information Center

    Brenner, Laurie A.; Turner, Katherine C.; Muller, Ralph-Axel

    2007-01-01

    Although atypical eye gaze is commonly observed in autism, little is known about underlying oculomotor abnormalities. Our review of visual search and oculomotor systems in the healthy brain suggests that relevant networks may be partially impaired in autism, given regional abnormalities known from neuroimaging. However, direct oculomotor evidence…

  14. Movement Pattern and Parameter Learning in Children: Effects of Feedback Frequency

    ERIC Educational Resources Information Center

    Goh, Hui-Ting; Kantak, Shailesh S.; Sullivan, Katherine J.

    2012-01-01

    Reduced feedback during practice has been shown to be detrimental to movement accuracy in children but not in young adults. We hypothesized that the reduced accuracy is attributable to reduced movement parameter learning, but not pattern learning, in children. A rapid arm movement task that required the acquisition of a motor pattern scaled to…

  15. Abnormal Patterns of Tongue-Palate Contact in the Speech of Individuals with Cleft Palate

    ERIC Educational Resources Information Center

    Gibbon, Fiona E.

    2004-01-01

    Individuals with cleft palate, even those with adequate velopharyngeal function, are at high risk for disordered lingual articulation. This article attempts to summarize current knowledge of abnormal tongue-palate contact patterns derived from electropalatographic (EPG) data in speakers with cleft palate. These data, which have been reported in 23…

  16. Classification of Lower Extremity Movement Patterns Based on Visual Assessment: Reliability and Correlation With 2-Dimensional Video Analysis

    PubMed Central

    Harris-Hayes, Marcie; Steger-May, Karen; Koh, Christine; Royer, Nat K.; Graci, Valentina; Salsich, Gretchen B.

    2014-01-01

    Context: Abnormal movement patterns have been implicated in lower extremity injury. Reliable, valid, and easily implemented assessment methods are needed to examine existing musculoskeletal disorders and investigate predictive factors for lower extremity injury. Objective: To determine the reliability of experienced and novice testers in making visual assessments of lower extremity movement patterns and to characterize the construct validity of the visual assessments. Design: Cross-sectional study. Setting: University athletic department and research laboratory. Patients or Other Participants: Convenience sample of 30 undergraduate and graduate students who regularly participate in athletics (age = 19.3 ± 4.5 years). Testers were 2 experienced physical therapists and 1 novice postdoctoral fellow (nonclinician). Main Outcome Measure(s): We took videos of 30 athletes performing the single-legged squat. Three testers observed the videos on 2 occasions and classified the lower extremity movement as dynamic valgus, no change, or dynamic varus. The classification was based on the estimated change in frontal-plane projection angle (FPPA) of the knee from single-legged stance to maximum single-legged squat depth. The actual FPPA change was measured quantitatively. We used percentage agreement and weighted κ to examine tester reliability and to determine construct validity of the visual assessment. Results: The κ values for intratester and intertester reliability ranged from 0.75 to 0.90, indicating substantial to excellent reliability. Percentage agreement between the visual assessment and the quantitative FPPA change category was 90%, with a κ value of 0.85. Conclusions: Visual assessments were made reliably by experienced and novice testers. Additionally, movement-pattern categories based on visual assessments were in excellent agreement with objective methods to measure FPPA change. Therefore, visual assessments can be used in the clinic to assess movement patterns

  17. Abnormal Image Detection in Endoscopy Videos Using a Filter Bank and Local Binary Patterns

    PubMed Central

    Nawarathna, Ruwan; Oh, JungHwan; Muthukudage, Jayantha; Tavanapong, Wallapak; Wong, Johnny; de Groen, Piet C.; Tang, Shou Jiang

    2014-01-01

    Finding mucosal abnormalities (e.g., erythema, blood, ulcer, erosion, and polyp) is one of the most essential tasks during endoscopy video review. Since these abnormalities typically appear in a small number of frames (around 5% of the total frame number), automated detection of frames with an abnormality can save physician’s time significantly. In this paper, we propose a new multi-texture analysis method that effectively discerns images showing mucosal abnormalities from the ones without any abnormality since most abnormalities in endoscopy images have textures that are clearly distinguishable from normal textures using an advanced image texture analysis method. The method uses a “texton histogram” of an image block as features. The histogram captures the distribution of different “textons” representing various textures in an endoscopy image. The textons are representative response vectors of an application of a combination of Leung and Malik (LM) filter bank (i.e., a set of image filters) and a set of Local Binary Patterns on the image. Our experimental results indicate that the proposed method achieves 92% recall and 91.8% specificity on wireless capsule endoscopy (WCE) images and 91% recall and 90.8% specificity on colonoscopy images. PMID:25132723

  18. Frequency and patterns of abnormal Pap smears in Sudanese women with infertility: What are the perspectives?

    PubMed Central

    Almobarak, Ahmed O; Elhoweris, Mohammed H; Nour, Hilmi M; Ahmed, Mohammed Abd Allah M; Omer, Al-Fadhil Alobeed; Ahmed, Mohamed H

    2013-01-01

    Background: Pelvic inflammatory disease is one of the major causes of infertility in females. Also, women with infertility are at high-risk of developing cervical intraepithelial lesions or even carcinoma. Aim: To assess the prevalence and patterns of epithelial cell abnormalities in cervical smears in Sudanese infertile and fertile women. Materials and Methods: The present study included 200 cases (women with infertility) of age group 20-60 years who had routine pap smear. A total of 700 fertile women constituted the control group. Results: Among the 200 infertile women, 93.5% reported as negative for intraepithelial lesion or malignancy (NILM), and 6.5% were epithelial cell abnormalities (atypical squamous cells of undetermined significance and above). In the control group 96.6% of the smears reported as NILM and 3.4% as epithelial cell abnormalities. The percentage of abnormal pap smears in the infertile women was significantly higher when compared with the control group. Conclusions: Epithelial cell abnormalities are significantly higher in women with infertility as compared with fertile women. Importantly, inflammatory smears were reported two times more than in the controls. We recommend pap smear as a routine practice for all women assessed for infertility problems. Further studies are necessary to evaluate the incidence of human papilloma virus infections in infertile women with abnormal cervical cytology. PMID:23833398

  19. Movement Pattern Variability in Stone Knapping: Implications for the Development of Percussive Traditions

    PubMed Central

    Rein, Robert; Nonaka, Tetsushi; Bril, Blandine

    2014-01-01

    The earliest direct evidence for tool-use by our ancestors are 2.6 million year old stone tools from Africa. These earliest artifacts show that, already, early hominins had developed the required advanced movement skills and cognitive capacities to manufacture stone tools. Currently, it is not well understood, however, which specific movement skills are required for successful stone knapping and accordingly it is unknown how these skills emerged during early hominin evolution. In particular, it is not clear which striking movements are indicative of skilled performance, how striking movement patterns vary with task and environmental constraints, and how movement patterns are passed on within social groups. The present study addresses these questions by investigating striking movement patterns and striking variability in 18 modern stone knappers (nine experienced and nine novices). The results suggest that no single movement pattern characterizes successful stone knapping. Participants showed large inter-individual movement variability of the elementary knapping action irrespective of knapping experience and knapping performance. Changes in task- and environmental constraints led knappers to adapt their elementary striking actions using a combination of individual and common strategies. Investigation of striking pattern similarities within social groups showed only partial overlap of striking patterns across related individuals. The results therefore suggest that striking movement patterns in modern stone knappers are largely specific to the individual and movement variability is not indicative of knapping performance. The implications of these results for the development of percussive traditions are discussed. PMID:25426630

  20. A mouse model of conduction system patterning abnormalities in heterotaxy syndrome.

    PubMed

    Czosek, Richard J; Haaning, Allison; Ware, Stephanie M

    2010-10-01

    Duplication or absence of parts of the specialized cardiac conduction system in patients with heterotaxy syndrome causes significant clinical disease, but the mechanistic basis by which embryonic disruption of left-right patterning alters conduction system patterning in these patients is not well understood. We sought to determine whether a mouse model of X-linked human heterotaxy recapitulates conduction system abnormalities identified in patients with heterotaxy. Cardiac structure and conduction system patterning were evaluated in Zic3 null embryos from e9.5 to e16.5 using genetic and molecular methods. Severe structural abnormalities involving atrial, ventricular, and conotruncal development were associated with a spectrum of disorganized and ambiguous arrangements throughout the conduction system, including the appearance of duplicated structures. The severity and location of conduction system abnormalities correlated with the severity and location of associated structural heart disease and were identifiable at the earliest stages examined. The Zic3 mouse model provides a novel tool to dissect the mechanistic underpinnings of conduction system patterning and dysfunction and its relationship to cardiovascular malformations, making it a promising model to improve understanding and risk assessment in the clinical arena.

  1. Visual control of movement patterns and the grammar of action.

    PubMed

    Smyth, M M

    1989-05-01

    In this experiment adult subjects copied three types of material (letters, reversed letters and geometric shapes) with and without sight of the hand and the writing trace. Without vision the number of movement segments decreased and the sequence and direction of movements were altered. This means that subjects did not use a fixed stored representation to produce items nor did they obey the rules of Goodnow and Levine's (1973) grammar of action. When spatial location is made more difficult by the removal of vision, movement production is simplified to reduce the number of relocations required. The use of consistent directions of movement depends on the ability to use visual control of spatial location.

  2. Unsupervised Pattern Classifier for Abnormality-Scaling of Vibration Features for Helicopter Gearbox Fault Diagnosis

    NASA Technical Reports Server (NTRS)

    Jammu, Vinay B.; Danai, Kourosh; Lewicki, David G.

    1996-01-01

    A new unsupervised pattern classifier is introduced for on-line detection of abnormality in features of vibration that are used for fault diagnosis of helicopter gearboxes. This classifier compares vibration features with their respective normal values and assigns them a value in (0, 1) to reflect their degree of abnormality. Therefore, the salient feature of this classifier is that it does not require feature values associated with faulty cases to identify abnormality. In order to cope with noise and changes in the operating conditions, an adaptation algorithm is incorporated that continually updates the normal values of the features. The proposed classifier is tested using experimental vibration features obtained from an OH-58A main rotor gearbox. The overall performance of this classifier is then evaluated by integrating the abnormality-scaled features for detection of faults. The fault detection results indicate that the performance of this classifier is comparable to the leading unsupervised neural networks: Kohonen's Feature Mapping and Adaptive Resonance Theory (AR72). This is significant considering that the independence of this classifier from fault-related features makes it uniquely suited to abnormality-scaling of vibration features for fault diagnosis.

  3. Abnormalities in myelination of the superior cerebellar peduncle in patients with schizophrenia and deficits in movement sequencing.

    PubMed

    Hüttlova, Jitka; Kikinis, Zora; Kerkovsky, Milos; Bouix, Sylvain; Vu, Mai-Anh; Makris, Nikos; Shenton, Martha; Kasparek, Tomas

    2014-08-01

    Deficits in the execution of a sequence of movements are common in schizophrenia. Previous studies reported reduced functional activity in the motor cortex and cerebellum in schizophrenic patients with deficits in movement sequencing. The corticospinal tract (CST) and superior cerebellar peduncle (SCP) are fiber tracts that are involved in movement sequencing. However, the integrity of these tracts has not been evaluated in schizophrenic patients with respect to the performance of movement sequencing yet. Diffusion tensor magnetic resonance images (DT-MRI) were acquired from 24 patients with schizophrenia and 23 matched control subjects. Tractography was applied to reconstruct the CST and SCP and DT-MRI-specific parameters such as fractional anisotropy (FA) and radial diffusivity (RD) were reported. The patient group was further subdivided based on the score of sequencing of complex motor acts subscale of the Neurological Evaluation Scale into those with deficits in sequencing motor acts, the SQ(abn) group (n = 7), and those with normal performance, the SQ(norm) group (n = 17). Schizophrenia patients of the SQ(norm) subgroup had significantly reduced FA and increased RD values in the right CST in comparison to the control group; the SQ(abn) subgroup did not differ from the controls. However, the SQ(abn) subgroup showed impaired integrity of the left SCP, whereas the SQ(norm) subgroup did not. Abnormalities in the right CST in the SQ(norm) and in the left SCP in SQ(abn) groups suggest that the patients with SQ(abn) represent subgroups with distinct deficits. Moreover, these results demonstrate the involvement of the SCP in the pathogenesis of movement sequencing in schizophrenia.

  4. The effects of crowding on eye movement patterns in reading.

    PubMed

    Bricolo, Emanuela; Salvi, Carola; Martelli, Marialuisa; Arduino, Lisa S; Daini, Roberta

    2015-09-01

    Crowding is a phenomenon that characterizes normal periphery limiting letter identification when other letters surround the signal. We investigated the nature of the reading limitation of crowding by analyzing eye-movement patterns. The stimuli consisted of two items varying across trials for letter spacing (spaced, unspaced and increased size), lexicality (words or pseudowords), number of letters (4, 6, 8), and reading modality (oral and silent). In Experiments 1 and 2 (oral and silent reading, respectively) the results show that an increase in letter spacing induced an increase in the number of fixations and in gaze duration, but a reduction in the first fixation duration. More importantly, increasing letter size (Experiment 3) produced the same first fixation duration advantage as empty spacing, indicating that, as predicted by crowding, only center-to-center letter distance, and not spacing per se, matters. Moreover, when the letter size was enlarged the number of fixations did not increase as much as in the previous experiments, suggesting that this measure depends on visual acuity rather than on crowding. Finally, gaze duration, a measure of word recognition, did not change with the letter size enlargement. No qualitative differences were found between oral and silent reading experiments (1 and 2), indicating that the articulatory process did not influence the outcome. Finally, a facilitatory effect of lexicality was found in all conditions, indicating an interaction between perceptual and lexical processing. Overall, our results indicate that crowding influences normal word reading by means of an increase in first fixation duration, a measure of word encoding, which we interpret as a modulatory effect of attention on critical spacing.

  5. The effects of crowding on eye movement patterns in reading.

    PubMed

    Bricolo, Emanuela; Salvi, Carola; Martelli, Marialuisa; Arduino, Lisa S; Daini, Roberta

    2015-09-01

    Crowding is a phenomenon that characterizes normal periphery limiting letter identification when other letters surround the signal. We investigated the nature of the reading limitation of crowding by analyzing eye-movement patterns. The stimuli consisted of two items varying across trials for letter spacing (spaced, unspaced and increased size), lexicality (words or pseudowords), number of letters (4, 6, 8), and reading modality (oral and silent). In Experiments 1 and 2 (oral and silent reading, respectively) the results show that an increase in letter spacing induced an increase in the number of fixations and in gaze duration, but a reduction in the first fixation duration. More importantly, increasing letter size (Experiment 3) produced the same first fixation duration advantage as empty spacing, indicating that, as predicted by crowding, only center-to-center letter distance, and not spacing per se, matters. Moreover, when the letter size was enlarged the number of fixations did not increase as much as in the previous experiments, suggesting that this measure depends on visual acuity rather than on crowding. Finally, gaze duration, a measure of word recognition, did not change with the letter size enlargement. No qualitative differences were found between oral and silent reading experiments (1 and 2), indicating that the articulatory process did not influence the outcome. Finally, a facilitatory effect of lexicality was found in all conditions, indicating an interaction between perceptual and lexical processing. Overall, our results indicate that crowding influences normal word reading by means of an increase in first fixation duration, a measure of word encoding, which we interpret as a modulatory effect of attention on critical spacing. PMID:26143298

  6. Fractal patterns of insect movement in microlandscape mosaics

    SciTech Connect

    Wiens, J.A.; Crist, T.O. |; With, K.A. |; Milne, B.T.

    1995-03-01

    How individuals move, whether in short-term searching behavior or long-term dispersal influences the probability that individuals will experience physiological stress or encounter appropriate habitat, potential mates, prey, or predators. Because of variety and complexity, it is often difficult to make sense of movements. Because the fractal dimension of a movement pathway is scale independent, however, it may provide a useful measure for comparing dissimilar taxa. The authors use fractal measures to compare the movement pathways of individual beetles occupying semiarid shortgrass steppe in north-central Colorado. 20 refs., 1 fig., 1 tab.

  7. Movement preparation and execution: differential functional activation patterns after traumatic brain injury.

    PubMed

    Gooijers, Jolien; Beets, Iseult A M; Albouy, Genevieve; Beeckmans, Kurt; Michiels, Karla; Sunaert, Stefan; Swinnen, Stephan P

    2016-09-01

    Years following the insult, patients with traumatic brain injury often experience persistent motor control problems, including bimanual coordination deficits. Previous studies revealed that such deficits are related to brain structural white and grey matter abnormalities. Here, we assessed, for the first time, cerebral functional activation patterns during bimanual movement preparation and performance in patients with traumatic brain injury, using functional magnetic resonance imaging. Eighteen patients with moderate-to-severe traumatic brain injury (10 females; aged 26.3 years, standard deviation = 5.2; age range: 18.4-34.6 years) and 26 healthy young adults (15 females; aged 23.6 years, standard deviation = 3.8; age range: 19.5-33 years) performed a complex bimanual tracking task, divided into a preparation (2 s) and execution (9 s) phase, and executed either in the presence or absence of augmented visual feedback. Performance on the bimanual tracking task, expressed as the average target error, was impaired for patients as compared to controls (P < 0.001) and for trials in the absence as compared to the presence of augmented visual feedback (P < 0.001). At the cerebral level, movement preparation was characterized by reduced neural activation in the patient group relative to the control group in frontal (bilateral superior frontal gyrus, right dorsolateral prefrontal cortex), parietal (left inferior parietal lobe) and occipital (right striate and extrastriate visual cortex) areas (P's < 0.05). During the execution phase, however, the opposite pattern emerged, i.e. traumatic brain injury patients showed enhanced activations compared with controls in frontal (left dorsolateral prefrontal cortex, left lateral anterior prefrontal cortex, and left orbitofrontal cortex), parietal (bilateral inferior parietal lobe, bilateral superior parietal lobe, right precuneus, right primary somatosensory cortex), occipital (right striate and extrastriate visual cortices), and

  8. Movement preparation and execution: differential functional activation patterns after traumatic brain injury.

    PubMed

    Gooijers, Jolien; Beets, Iseult A M; Albouy, Genevieve; Beeckmans, Kurt; Michiels, Karla; Sunaert, Stefan; Swinnen, Stephan P

    2016-09-01

    Years following the insult, patients with traumatic brain injury often experience persistent motor control problems, including bimanual coordination deficits. Previous studies revealed that such deficits are related to brain structural white and grey matter abnormalities. Here, we assessed, for the first time, cerebral functional activation patterns during bimanual movement preparation and performance in patients with traumatic brain injury, using functional magnetic resonance imaging. Eighteen patients with moderate-to-severe traumatic brain injury (10 females; aged 26.3 years, standard deviation = 5.2; age range: 18.4-34.6 years) and 26 healthy young adults (15 females; aged 23.6 years, standard deviation = 3.8; age range: 19.5-33 years) performed a complex bimanual tracking task, divided into a preparation (2 s) and execution (9 s) phase, and executed either in the presence or absence of augmented visual feedback. Performance on the bimanual tracking task, expressed as the average target error, was impaired for patients as compared to controls (P < 0.001) and for trials in the absence as compared to the presence of augmented visual feedback (P < 0.001). At the cerebral level, movement preparation was characterized by reduced neural activation in the patient group relative to the control group in frontal (bilateral superior frontal gyrus, right dorsolateral prefrontal cortex), parietal (left inferior parietal lobe) and occipital (right striate and extrastriate visual cortex) areas (P's < 0.05). During the execution phase, however, the opposite pattern emerged, i.e. traumatic brain injury patients showed enhanced activations compared with controls in frontal (left dorsolateral prefrontal cortex, left lateral anterior prefrontal cortex, and left orbitofrontal cortex), parietal (bilateral inferior parietal lobe, bilateral superior parietal lobe, right precuneus, right primary somatosensory cortex), occipital (right striate and extrastriate visual cortices), and

  9. An Investigation of Horizontal Combined Eye-Head Tracking in Patients with Abnormal Vestibular and Smooth Pursuit Eye Movements

    NASA Technical Reports Server (NTRS)

    Huebner, William P.; Leigh, R. John; Seidman, Scott H.; Billian, Carl

    1993-01-01

    We investigated the interaction of smooth ocular pursuit (SP) and the vestibulo-ocular reflex (VOR) during horizontal, combined eye-head tracking (CEHT) in patients with abnormalities of either the VOR or SP movements. Our strategy was to apply transient stimuli that capitalized on the different latencies to onset of SP and the VOR. During CEHT of a target moving at 15 deg/sec, normal subjects and patients with VOR deficits all tracked the target with a gain close to 1.O. When the heads of normal subjects were suddenly and unexpectedly braked to a halt during CEHT, the eye promptly began to move in the orbit to track the target, but eye-in-orbit velocity transiently fell to about 60-70% of target velocity. In patients with deficient labyrinthine function, following the onset of the head brake, eye movements to track the target were absent, and SP movements were not generated until about 100 msec later. In patients with deficient SP, CEHT was superior to SP tracking with the head stationary; after the onset of the head brake, tracking eye movements were initiated promptly, but eye velocity was less than 50% of target velocity and increased only slightly thereafter. These results indicate that at least two mechanisms operate to overcome the VOR and allow gaze to track the target during CEHT: (1) the SP system provides a signal to cancel a normally-operating VOR (this cancellation signal is not needed by labyrinthine-deficient patients who have no VOR to cancel), and (2) a reduction of the gain of the VOR is achieved, an ability that is preserved even in patients with cerebral lesions that impair SP.

  10. Teachers' knowledge of normal and abnormal elimination patterns in elementary school children.

    PubMed

    Boyt, Margaret A

    2005-12-01

    Dysfunctional elimination may be learned, to some degree. Because children spend nearly half of their waking hours at school, there is the potential for school to have a significant impact on their elimination patterns. Surveys were mailed to 1,000 randomly selected Iowa public elementary school teachers; 467 of the surveys were returned. Findings indicate that most elementary school teachers are unaware of the potential health problems of elimination dysfunction. One third of respondents indicated that they ask children to wait to go to the bathroom. Suboptimal conditions exist in most of the school bathrooms, with only 35% of the boys' restrooms and 48% of the girls' restrooms reported as "always clean." Those teachers with more experience were more likely to report information about abnormal elimination to the school nurse. Very few teachers (18% of respondents) reported having received information about abnormal elimination and even fewer (8% of respondents) were aware of specialists trained to treat children with these problems. School nurses can have a significant impact on the development of healthy bladder habits in children. Teachers need information about normal and abnormal elimination patterns in children. PMID:16285844

  11. Modifying patterns of movement in people with low back pain -does it help? A systematic review

    PubMed Central

    2012-01-01

    Background Physiotherapy for people with low back pain frequently includes assessment and modification of lumbo-pelvic movement. Interventions commonly aim to restore normal movement and thereby reduce pain and improve activity limitation. The objective of this systematic review was to investigate: (i) the effect of movement-based interventions on movement patterns (muscle activation, lumbo-pelvic kinematics or postural patterns) of people with low back pain (LBP), and (ii) the relationship between changes in movement patterns and subsequent changes in pain and activity limitation. Methods MEDLINE, Cochrane Central, EMBASE, AMI, CINAHL, Scopus, AMED, ISI Web of Science were searched from inception until January 2012. Randomised controlled trials or controlled clinical trials of people with LBP were eligible for inclusion. The intervention must have been designed to influence (i) muscle activity patterns, (ii) lumbo-pelvic kinematic patterns or (iii) postural patterns, and included measurement of such deficits before and after treatment, to allow determination of the success of the intervention on the lumbo-pelvic movement. Twelve trials (25% of retrieved studies) met the inclusion criteria. Two reviewers independently identified, assessed and extracted data. The PEDro scale was used to assess method quality. Intervention effects were described using standardised differences between group means and 95% confidence intervals. Results The included trials showed inconsistent, mostly small to moderate intervention effects on targeted movement patterns. There was considerable heterogeneity in trial design, intervention type and outcome measures. A relationship between changes to movement patterns and improvements in pain or activity limitation was observed in one of six studies on muscle activation patterns, one of four studies that examined the flexion relaxation response pattern and in two of three studies that assessed lumbo-pelvic kinematics or postural

  12. Abnormal Brain Connectivity Patterns in Adults with ADHD: A Coherence Study

    PubMed Central

    Sato, João Ricardo; Hoexter, Marcelo Queiroz; Castellanos, Xavier Francisco; Rohde, Luis A.

    2012-01-01

    Studies based on functional magnetic resonance imaging (fMRI) during the resting state have shown decreased functional connectivity between the dorsal anterior cingulate cortex (dACC) and regions of the Default Mode Network (DMN) in adult patients with Attention-Deficit/Hyperactivity Disorder (ADHD) relative to subjects with typical development (TD). Most studies used Pearson correlation coefficients among the BOLD signals from different brain regions to quantify functional connectivity. Since the Pearson correlation analysis only provides a limited description of functional connectivity, we investigated functional connectivity between the dACC and the posterior cingulate cortex (PCC) in three groups (adult patients with ADHD, n = 21; TD age-matched subjects, n = 21; young TD subjects, n = 21) using a more comprehensive analytical approach – unsupervised machine learning using a one-class support vector machine (OC-SVM) that quantifies an abnormality index for each individual. The median abnormality index for patients with ADHD was greater than for TD age-matched subjects (p = 0.014); the ADHD and young TD indices did not differ significantly (p = 0.480); the median abnormality index of young TD was greater than that of TD age-matched subjects (p = 0.016). Low frequencies below 0.05 Hz and around 0.20 Hz were the most relevant for discriminating between ADHD patients and TD age-matched controls and between the older and younger TD subjects. In addition, we validated our approach using the fMRI data of children publicly released by the ADHD-200 Competition, obtaining similar results. Our findings suggest that the abnormal coherence patterns observed in patients with ADHD in this study resemble the patterns observed in young typically developing subjects, which reinforces the hypothesis that ADHD is associated with brain maturation deficits. PMID:23049834

  13. Arthroscopic Visualization of Abnormal Movement of Discoid Lateral Meniscus With Snapping Phenomenon.

    PubMed

    Harato, Kengo; Niki, Yasuo; Nagashima, Masaki; Masumoto, Ko; Otani, Toshiro; Toyama, Yoshiaki; Suda, Yasunori

    2015-06-01

    Discoid lateral meniscus with snapping phenomenon is a rare pathologic condition. The purpose of this article is to present an arthroscopic technique for the treatment of discoid lateral meniscus with snapping phenomenon. The patient is placed in the supine position for confirmation of snapping. As the patient's knee bends, it can be confirmed by arthroscopy that the posterior horn of the discoid lateral meniscus moves posteriorly and the central portion of the discoid lateral meniscus moves anteriorly at the same time with snapping at deep flexion angles. The anterior segment of the discoid lateral meniscus is found to be redundant and is often folded. On the contrary, as the patient's knee extends, the central portion is returned to the original position accompanied by snapping at nearly full extension. After excision of the central portion, the movement of the meniscus is evaluated again and the disappearance of the snapping phenomenon can be confirmed. Although it includes limitations, this application is easy and would certainly help surgeons to treat snapping knee with discoid lateral meniscus.

  14. Elevated PEM (Phasic Electromyographic Metric) Rates Identify Rapid Eye Movement Behavior Disorder Patients on Nights Without Behavioral Abnormalities

    PubMed Central

    Bliwise, Donald L.; Rye, David B.

    2008-01-01

    Objective: To determine the validity of the phasic electromyographic metric (PEM) to differentiate patients with a history suggestive of rapid eye movement behavior disorder (REMBD) on laboratory nights without overt dream-enactment behavior. Methods: PEM was quantified as the % of 2.5-sec intervals with phasic muscle activity of 100-msec duration with an amplitude of at least 4 times background activity in 11 patients and 31 elderly controls. Data were derived from both REM and NREM sleep from 5 muscle groups (mentalis, left/right anterior tibialis, left/right brachioradialis). Results: Relative to controls, REMBD patients had significantly higher levels of PEM activity in all recordings. The largest differences occurred during REM sleep for the mentalis and brachioradialis channels. Similar results were obtained by limiting quantification of PEM to the final REM period of the night and could be accomplished by individuals with no previous familiarity with polysomnography. Discussion: PEM may be a useful metric to characterize the REM related phasic muscle activity on patients with a history of REMBD, even when no overt dream-enactment behaviors are detected on a laboratory night. Citation: Bliwise DL; Rye DB. Elevated PEM (phasic electromyographic metric) rates identify rapid eye movement behavior disorder patients on nights without behavioral abnormalities. SLEEP 2008;31(6):853–857. PMID:18548830

  15. Suitability of Kinect for measuring whole body movement patterns during exergaming.

    PubMed

    van Diest, Mike; Stegenga, Jan; Wörtche, Heinrich J; Postema, Klaas; Verkerke, Gijsbertus J; Lamoth, Claudine J C

    2014-09-22

    Exergames provide a challenging opportunity for home-based training and evaluation of postural control in the elderly population, but affordable sensor technology and algorithms for assessment of whole body movement patterns in the home environment are yet to be developed. The aim of the present study was to evaluate the use of Kinect, a commonly available video game sensor, for capturing and analyzing whole body movement patterns. Healthy adults (n=20) played a weight shifting exergame under five different conditions with varying amplitudes and speed of sway movement, while 3D positions of ten body segments were recorded in the frontal plane using Kinect and a Vicon 3D camera system. Principal Component Analysis (PCA) was used to extract and compare movement patterns and the variance in individual body segment positions explained by these patterns. Using the identified patterns, balance outcome measures based on spatiotemporal sway characteristics were computed. The results showed that both Vicon and Kinect capture >90% variance of all body segment movements within three PCs. Kinect-derived movement patterns were found to explain variance in trunk movements accurately, yet explained variance in hand and foot segments was underestimated and overestimated respectively by as much as 30%. Differences between both systems with respect to balance outcome measures range 0.3-64.3%. The results imply that Kinect provides the unique possibility of quantifying balance ability while performing complex tasks in an exergame environment.

  16. Emergent group level navigation: an agent-based evaluation of movement patterns in a folivorous primate.

    PubMed

    Bonnell, Tyler R; Campennì, Marco; Chapman, Colin A; Gogarten, Jan F; Reyna-Hurtado, Rafael A; Teichroeb, Julie A; Wasserman, Michael D; Sengupta, Raja

    2013-01-01

    The foraging activity of many organisms reveal strategic movement patterns, showing efficient use of spatially distributed resources. The underlying mechanisms behind these movement patterns, such as the use of spatial memory, are topics of considerable debate. To augment existing evidence of spatial memory use in primates, we generated movement patterns from simulated primate agents with simple sensory and behavioral capabilities. We developed agents representing various hypotheses of memory use, and compared the movement patterns of simulated groups to those of an observed group of red colobus monkeys (Procolobus rufomitratus), testing for: the effects of memory type (Euclidian or landmark based), amount of memory retention, and the effects of social rules in making foraging choices at the scale of the group (independent or leader led). Our results indicate that red colobus movement patterns fit best with simulated groups that have landmark based memory and a follow the leader foraging strategy. Comparisons between simulated agents revealed that social rules had the greatest impact on a group's step length, whereas the type of memory had the highest impact on a group's path tortuosity and cohesion. Using simulation studies as experimental trials to test theories of spatial memory use allows the development of insight into the behavioral mechanisms behind animal movement, developing case-specific results, as well as general results informing how changes to perception and behavior influence movement patterns.

  17. Abnormal joint torque patterns exhibited by chronic stroke subjects while walking with a prescribed physiological gait pattern

    PubMed Central

    Neckel, Nathan D; Blonien, Natalie; Nichols, Diane; Hidler, Joseph

    2008-01-01

    leg, both being typical abnormal torque synergy patterns common to stroke gait. Conclusion Despite the Lokomat guiding stroke subjects through physiologically symmetric kinematic gait patterns, abnormal asymmetric joint torque patterns are still generated. These differences from the control group are characteristic of the hip hike and circumduction strategy employed by stroke subjects. PMID:18761735

  18. Identifying Movement Patterns and Severity of Associated Pain in Sign Language Interpreters

    ERIC Educational Resources Information Center

    Freeman, Julie K.; Rogers, Janet L.

    2010-01-01

    Our research sought to identify the most common movement patterns and postures performed by sign language interpreters and the frequency and severity of any pain that may be associated with the movements. A survey was developed and mailed to registered sign language interpreters throughout the state of Illinois. For each specific upper extremity…

  19. Bilateral Transfer: The Effects of Practice on the Transfer of Complex Dance Movement Patterns.

    ERIC Educational Resources Information Center

    Puretz, Susan L.

    1983-01-01

    The effects of practice on the bilateral transfer of complex dance movement patterns were studied by having subjects learn two sequences under eight different conditions. Results indicate that teachers have been correct in expecting students to transfer movements bilaterally (from one side to the other) but should teach to the nonpreferred side.…

  20. Interacting noise sources shape patterns of arm movement variability in three-dimensional space.

    PubMed

    Apker, Gregory A; Darling, Timothy K; Buneo, Christopher A

    2010-11-01

    Reaching movements are subject to noise in both the planning and execution phases of movement production. The interaction of these noise sources during natural movements is not well understood, despite its importance for understanding movement variability in neurologically intact and impaired individuals. Here we examined the interaction of planning and execution related noise during the production of unconstrained reaching movements. Subjects performed sequences of two movements to targets arranged in three vertical planes separated in depth. The starting position for each sequence was also varied in depth with the target plane; thus required movement sequences were largely contained within the vertical plane of the targets. Each final target in a sequence was approached from two different directions, and these movements were made with or without visual feedback of the moving hand. These combined aspects of the design allowed us to probe the interaction of execution and planning related noise with respect to reach endpoint variability. In agreement with previous studies, we found that reach endpoint distributions were highly anisotropic. The principal axes of movement variability were largely aligned with the depth axis, i.e., the axis along which visual planning related noise would be expected to dominate, and were not generally well aligned with the direction of the movement vector. Our results suggest that visual planning-related noise plays a dominant role in determining anisotropic patterns of endpoint variability in three-dimensional space, with execution noise adding to this variability in a movement direction-dependent manner.

  1. Observations of elk movement patterns on Fossil Butte National Monument

    USGS Publications Warehouse

    Olexa, Edward M.; Soileau, Suzanna Carrithers.; Allen, Leslie A.

    2014-01-01

    The elk herd that frequents Fossil Butte National Monument, a subset of the West Green River elk population, provides visitors with seasonal opportunities to view an iconic species of the western United States. Throughout the year, these elk range across a variety of private, State, and Federal lands within close proximity to the Monument. These lands are managed differently for various uses which can create challenging wildlife-management issues and influence the herd’s seasonal movements and distribution. Research lead by the USGS investigates some of the factors associated with these seasonal changes.

  2. Interactive Visual Discovering of Movement Patterns from Sparsely Sampled Geo-tagged Social Media Data.

    PubMed

    Chen, Siming; Yuan, Xiaoru; Wang, Zhenhuang; Guo, Cong; Liang, Jie; Wang, Zuchao; Zhang, Xiaolong Luke; Zhang, Jiawan

    2016-01-01

    Social media data with geotags can be used to track people's movements in their daily lives. By providing both rich text and movement information, visual analysis on social media data can be both interesting and challenging. In contrast to traditional movement data, the sparseness and irregularity of social media data increase the difficulty of extracting movement patterns. To facilitate the understanding of people's movements, we present an interactive visual analytics system to support the exploration of sparsely sampled trajectory data from social media. We propose a heuristic model to reduce the uncertainty caused by the nature of social media data. In the proposed system, users can filter and select reliable data from each derived movement category, based on the guidance of uncertainty model and interactive selection tools. By iteratively analyzing filtered movements, users can explore the semantics of movements, including the transportation methods, frequent visiting sequences and keyword descriptions. We provide two cases to demonstrate how our system can help users to explore the movement patterns.

  3. Extraction of practice-dependent and practice-independent finger movement patterns.

    PubMed

    Furuya, Shinichi; Nakamura, Ayumi; Nagata, Noriko

    2014-08-01

    Extensive motor practice can reorganize movements of a redundant number of degrees of freedom (DOFs). Using principal component (PC) analysis, the present study characterized the movement reorganization of the hand that possesses a large number of DOFs during a course of practice. Five musically naïve individuals practiced to play a short sequence of melody with the left hand for four successive days, and their hand kinematics was measured using a motion capture system. The PC analysis of the hand joint kinematics identified two distinct patterns of movement, which accounted for more than 80% of the total variance of movements. The second PC but not the first PC changed through practice. A correlation analysis demonstrated that the PC sensitive to the practice was characterized by coupled movements across fingers in the same direction. A regression analysis identified a decrease in the contribution of this PC to the hand movement organization through practice, which indicates a reduction of the movement covariation across fingers and thus an enhancement of the individuated finger movements. The results implicate potential of PC analysis to extract practice-invariant and practice-dependent movement patterns distinctively in complex hand motor behaviors. PMID:24933539

  4. Coarse-scale movement patterns of a small-bodied fish inhabiting a desert stream

    USGS Publications Warehouse

    Dzul, M.C.; Quist, M.C.; Dinsmore, S.J.; Gaines, D.B.; Bower, M.R.

    2013-01-01

    Located on the floor of Death Valley (CA, USA), Salt Creek harbors a single fish species, the Salt Creek pupfish, Cyprinodon salinus salinus, which has adapted to this extremely harsh environment. Salt Creek is fed by an underground spring and is comprised of numerous pools, runs, and marshes that exhibit substantial variability in temperature, salinity, and dissolved oxygen concentrations. In addition, the wetted area of Salt Creek is reduced throughout the summer months due to high rates of evaporation, with some reaches drying completely. Therefore, it seems logical that short- and long-term movement patterns may play an important role in Salt Creek pupfish population dynamics. The objective of this study was to describe coarse-scale movements of Salt Creek pupfish in Salt Creek during their breeding season from March to May. Sex ratios and length–frequency distributions varied spatially within Salt Creek, suggesting population segregation during the breeding season. Long-distance movements were generally rare, although two fish moved more than 1.2 km. Movement in upstream reaches was rare or absent, in contrast to the greater movement observed in downstream reaches (29% of recaptures). Temporal trends and demographic patterns in movement were not observed. Because the two most downstream habitats dry up in the summer, our results indicate that coarse-scale movements that re-populate downstream reaches likely occur during other times of year. Consequently, the importance of small- and large-scale movements is influenced by season. Further assessment of Salt Creek movement patterns conducted during other times of year may better illuminate long-distance movement patterns and source-sink dynamics.

  5. Neural code alterations and abnormal time patterns in Parkinson’s disease

    NASA Astrophysics Data System (ADS)

    Andres, Daniela Sabrina; Cerquetti, Daniel; Merello, Marcelo

    2015-04-01

    Objective. The neural code used by the basal ganglia is a current question in neuroscience, relevant for the understanding of the pathophysiology of Parkinson’s disease. While a rate code is known to participate in the communication between the basal ganglia and the motor thalamus/cortex, different lines of evidence have also favored the presence of complex time patterns in the discharge of the basal ganglia. To gain insight into the way the basal ganglia code information, we studied the activity of the globus pallidus pars interna (GPi), an output node of the circuit. Approach. We implemented the 6-hydroxydopamine model of Parkinsonism in Sprague-Dawley rats, and recorded the spontaneous discharge of single GPi neurons, in head-restrained conditions at full alertness. Analyzing the temporal structure function, we looked for characteristic scales in the neuronal discharge of the GPi. Main results. At a low-scale, we observed the presence of dynamic processes, which allow the transmission of time patterns. Conversely, at a middle-scale, stochastic processes force the use of a rate code. Regarding the time patterns transmitted, we measured the word length and found that it is increased in Parkinson’s disease. Furthermore, it showed a positive correlation with the frequency of discharge, indicating that an exacerbation of this abnormal time pattern length can be expected, as the dopamine depletion progresses. Significance. We conclude that a rate code and a time pattern code can co-exist in the basal ganglia at different temporal scales. However, their normal balance is progressively altered and replaced by pathological time patterns in Parkinson’s disease.

  6. Young School Children's Recess Physical Activity: Movement Patterns and Preferences

    ERIC Educational Resources Information Center

    Woods, Amelia M.; Graber, Kim C.; Daum, David N.; Gentry, Chris

    2015-01-01

    This study examined physical activity (PA) variables related to recess PA patterns of kindergarten, first and second grade children, and the social preferences and individuals influencing their PA. Data collected (N = 147) used the System of Observing Children's Activity and Relationships during Play (SOCARP) instrument. Children were interviewed.…

  7. Children's Recess Physical Activity: Movement Patterns and Preferences

    ERIC Educational Resources Information Center

    Woods, Amelia Mays; Graber, Kim C.; Daum, David Newman

    2012-01-01

    The benefits of recess can be reaped by all students regardless of socioeconomic status, race, or gender and at relatively little cost. The purpose of this study was to examine physical activity (PA) variables related to the recess PA patterns of third and fourth grade children and the social preferences and individuals influencing their PA…

  8. Movement and spatial proximity patterns of rangeland-raised Raramuri Criollo cow-calf pairs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to compare movement patterns of nursing vs. nonnursing mature cows and to characterize cow-calf proximity patterns in two herds of Raramuri Criollo cattle. Herds grazed rangeland pastures in southern New Mexico (4355 ha) and west-central Chihuahua, Mexico (633 ha)'' A...

  9. Abnormal methylation pattern in constitutive and facultative heterochromatin of ICF patients

    SciTech Connect

    Miniou, P.; Blanquet, V.; Viegas-Pequignot, E.

    1994-09-01

    ICF syndrome is a rare autosomal recessive disease, characterized by variable immunodeficiency, centromeric instability and facial abnormalities. Stretchings and frequent associations of centromeric or juxtacentromeric heterochromatin of chromosome 1 and 16 principally, and to a lesser degree, chromosome 9 mimic chromosome features of normal PHA-stimulated lymphocytes treated with 5-azacytidine, an inducer of demethylation. In fact, in these patients we have detected by DNA digestion with methyl-sensitive enzymes a hypomethylation of classical satellites 2 and 3, located in heterochromatin. To assess the role of other satellite DNA in the heterochromatin modifications and chromosome rearrangements, in situ fluorescent method using 5-methylcytosine (5-MeC) monoclonal antibody on chromosomes and nuclei were performed in parallel with Southern blot analysis of other satellite sequences located in heterochromatin. 5-MeC reveals that constitutive and facultative heterochromatin (X inactive chromosome) are hypomethylated. Alpha satellite sequences corresponding to centromeric heterochromatin of chromosomes 1, 3, 6, 9, 16, 18 and X are mostly methylated in patients G and R, and are undermethylated in patient S. Both molecular and cytogenetic analysis are in agreement. By in situ hybridization, breakpoints of rearranged chromosomes were located in stretched and hypomethylated classical satellites. In euchromatin, 5-MeC antibodies reveal an R-like banding pattern indicating an unequal distribution of DNA methylation, disclosing another aspect of chromosome organization. The underlying hypomethylation, associated with an abnormal chromatin structure, may predispose to chromosome instability.

  10. Abnormal changes of multidimensional surface features using multivariate pattern classification in amnestic mild cognitive impairment patients.

    PubMed

    Li, Shuyu; Yuan, Xiankun; Pu, Fang; Li, Deyu; Fan, Yubo; Wu, Liyong; Chao, Wang; Chen, Nan; He, Yong; Han, Ying

    2014-08-01

    Previous studies have suggested that amnestic mild cognitive impairment (aMCI) is associated with changes in cortical morphological features, such as cortical thickness, sulcal depth, surface area, gray matter volume, metric distortion, and mean curvature. These features have been proven to have specific neuropathological and genetic underpinnings. However, most studies primarily focused on mass-univariate methods, and cortical features were generally explored in isolation. Here, we used a multivariate method to characterize the complex and subtle structural changing pattern of cortical anatomy in 24 aMCI human participants and 26 normal human controls. Six cortical features were extracted for each participant, and the spatial patterns of brain abnormities in aMCI were identified by high classification weights using a support vector machine method. The classification accuracy in discriminating the two groups was 76% in the left hemisphere and 80% in the right hemisphere when all six cortical features were used. Regions showing high weights were subtle, spatially complex, and predominately located in the left medial temporal lobe and the supramarginal and right inferior parietal lobes. In addition, we also found that the six morphological features had different contributions in discriminating the two groups even for the same region. Our results indicated that the neuroanatomical patterns that discriminated individuals with aMCI from controls were truly multidimensional and had different effects on the morphological features. Furthermore, the regions identified by our method could potentially be useful for clinical diagnosis. PMID:25100588

  11. Losing dexterity: patterns of impaired coordination of finger movements in musician’s dystonia

    PubMed Central

    Furuya, Shinichi; Tominaga, Kenta; Miyazaki, Fumio; Altenmüller, Eckart

    2015-01-01

    Extensive training can bring about highly-skilled action, but may also impair motor dexterity by producing involuntary movements and muscular cramping, as seen in focal dystonia (FD) and tremor. To elucidate the underlying neuroplastic mechanisms of FD, the present study addressed the organization of finger movements during piano performance in pianists suffering from the condition. Principal component (PC) analysis identified three patterns of fundamental joint coordination constituting finger movements in both patients and controls. The first two coordination patterns described less individuated movements between the “dystonic” finger and key-striking fingers for patients compared to controls. The third coordination pattern, representing the individuation of movements between the middle and ring fingers, was evident during a sequence of strikes with these fingers in controls, which was absent in the patients. Consequently, rhythmic variability of keystrokes was more pronounced during this sequence of strikes for the patients. A stepwise multiple-regression analysis further identified greater variability of keystrokes for individuals displaying less individuated movements between the affected and striking fingers. The findings suggest that FD alters dexterous joint coordination so as to lower independent control of finger movements, and thereby degrades fine motor control. PMID:26289433

  12. Measuring abnormal movements in free-swimming fish with accelerometers: implications for quantifying tag and parasite load.

    PubMed

    Broell, Franziska; Burnell, Celene; Taggart, Christopher T

    2016-03-01

    Animal-borne data loggers allow movement, associated behaviours and energy expenditure in fish to be quantified without direct observations. As with any tagging, tags that are attached externally may adversely affect fish behaviour, swimming efficiency and survival. We report on free-swimming wild Atlantic cod (Gadus morhua) held in a large mesocosm that exhibited distinctly aberrant rotational swimming (scouring) when externally tagged with accelerometer data loggers. To quantify the phenomenon, the cod were tagged with two sizes of loggers (18 and 6 g; <2% body mass) that measured tri-axial acceleration at 50 Hz. An automated algorithm, based on body angular rotation, was designed to extract the scouring movements from the acceleration signal (98% accuracy). The algorithm also identified the frequency pattern and associated energy expenditure of scouring in relation to tag load (% body weight). The average per cent time spent scouring (5%) was independent of tag load. The vector of the dynamic body acceleration (VeDBA), used as a proxy for energy expenditure, increased with tag load (r(2)=0.51), and suggests that fish with large tags spent more energy when scouring than fish with small tags. The information allowed us to determine potential detrimental effects of an external tag on fish behaviour and how these effects may be mitigated by tag size. The algorithm can potentially identify similar rotational movements associated with spawning, courtship, feeding and parasite-load shedding in the wild. The results infer a more careful interpretation of data derived from external tags and the careful consideration of tag type, drag, buoyancy and placement, as well as animal buoyancy and species. PMID:26747901

  13. Complex muscle vibration patterns to induce gait-like lower-limb movements: proof of concept.

    PubMed

    Duclos, Cyril; Kemlin, Claire; Lazert, David; Gagnon, Dany; Dyer, Joseph-Omer; Forget, Robert

    2014-01-01

    Muscle vibrations can induce motor responses and illusions of complex movements. However, inducing gait-like cyclical movements and illusions requires the application of multiple fast alternating vibrations to lower-limb muscles. The objectives were (1) to test the feasibility of delivering complex vibrations in a time-organized manner and (2) to illustrate the possibility of inducing alternate gait-in-place-like movements using these vibrations. Patterns of vibration, produced by 12 vibrators applied bilaterally on the flexor and extensor muscle groups of the lower limbs, were based on normal gait kinematics. We tested 1 s and 2 s cycle patterns of vibration. Vibrator responses were assessed using auto- and crosscorrelations and frequency analyses based on accelerometry measurements, and compared between patterns. High auto- (>0.8) and crosscorrelation (>0.6) coefficients demonstrated a good response by the vibrators to the control signal. Vibrations induced cyclical, low-amplitude stepping-in-place movements that mimicked alternate walking movements with both legs, with 1 s and 2 s cycle durations, in one nondisabled participant and one participant with American Spinal Injury Association Impairment Scale B spinal cord injury standing, relaxed, with body-weight support. Electromechanical vibrators can deliver complex cyclical vibrations and trigger gait-like lower-limb movements. These results warrant the application of these vibration patterns on individuals with sensorimotor impairments to test their potential in gait rehabilitation.

  14. Accurate means of detecting and characterizing abnormal patterns of ventricular activation by phase image analysis

    SciTech Connect

    Botvinick, E.H.; Frais, M.A.; Shosa, D.W.; O'Connell, J.W.; Pacheco-Alvarez, J.A.; Scheinman, M.; Hattner, R.S.; Morady, F.; Faulkner, D.B.

    1982-08-01

    The ability of scintigraphic phase image analysis to characterize patterns of abnormal ventricular activation was investigated. The pattern of phase distribution and sequential phase changes over both right and left ventricular regions of interest were evaluated in 16 patients with normal electrical activation and wall motion and compared with those in 8 patients with an artificial pacemaker and 4 patients with sinus rhythm with the Wolff-Parkinson-White syndrome and delta waves. Normally, the site of earliest phase angle was seen at the base of the interventricular septum, with sequential change affecting the body of the septum and the cardiac apex and then spreading laterally to involve the body of both ventricles. The site of earliest phase angle was located at the apex of the right ventricle in seven patients with a right ventricular endocardial pacemaker and on the lateral left ventricular wall in one patient with a left ventricular epicardial pacemaker. In each case the site corresponded exactly to the position of the pacing electrode as seen on posteroanterior and left lateral chest X-ray films, and sequential phase changes spread from the initial focus to affect both ventricles. In each of the patients with the Wolff-Parkinson-White syndrome, the site of earliest ventricular phase angle was located, and it corresponded exactly to the site of the bypass tract as determined by endocardial mapping. In this way, four bypass pathways, two posterior left paraseptal, one left lateral and one right lateral, were correctly localized scintigraphically. On the basis of the sequence of mechanical contraction, phase image analysis provides an accurate noninvasive method of detecting abnormal foci of ventricular activation.

  15. Movement patterns of stream-dwelling fishes from Mata Atlântica, Southeast Brazil.

    PubMed

    Mazzoni, Rosana; Iglesias-Rios, Ricardo

    2012-12-01

    The identification of mechanisms of spatial-temporal variation, obtained from the quantification of natural populations, is a central topic of ecological research. Despite its importance to life-history theory, as well as to conservation and management of natural populations, no studies concerning movement patterns and home range of small stream-dwelling fishes from Brazilian rain forests are known. In the present study we aimed to describe the longitudinal pattern of long distance movement as well as local patterns of short movement (daily home-range) of fishes from a Mata Atlântica stream from Southeast Brazil. We gathered information about movement dynamic in order to discuss the relationship between swimming ability, fish morphology and home range. Long distance movement data were obtained in a mark-recapture experiment held in the field between June and September - 2008, on five sites along the Ubatiba stream. For this study, we had one day to mark fishes, on June-19, and 14 events for recapture. Considering the ten species that inhabit the study area, our study showed that four species: Astyanax janeiroensis, Astyanax hastatus, Parotocinclus maculicauda and Pimelodella lateristriga, moved at least 6 000m in 60 days. The other six species did not present long distance movements, as they were recaptured in the same site 90 days after being marked. For short distance study, movement data were obtained in one mark-recapture experiment held in a 100m long site subdivided into five 20m stretches where fishes were marked with different elastomer colours. We marked 583 specimens that after recapture showed two groups of different movement patterns. The first group was called "Long Movement Group" and the second one was called "Short Movement Group". The Long Movement Group showed, on average, 89.8% of moving fishes and 10.2% of non moving fishes, against 21.3% and 78.7%, respectively, for the Short Movement Group. It was concluded that fish movement could explain

  16. Movement patterns of stream-dwelling fishes from Mata Atlântica, Southeast Brazil.

    PubMed

    Mazzoni, Rosana; Iglesias-Rios, Ricardo

    2012-12-01

    The identification of mechanisms of spatial-temporal variation, obtained from the quantification of natural populations, is a central topic of ecological research. Despite its importance to life-history theory, as well as to conservation and management of natural populations, no studies concerning movement patterns and home range of small stream-dwelling fishes from Brazilian rain forests are known. In the present study we aimed to describe the longitudinal pattern of long distance movement as well as local patterns of short movement (daily home-range) of fishes from a Mata Atlântica stream from Southeast Brazil. We gathered information about movement dynamic in order to discuss the relationship between swimming ability, fish morphology and home range. Long distance movement data were obtained in a mark-recapture experiment held in the field between June and September - 2008, on five sites along the Ubatiba stream. For this study, we had one day to mark fishes, on June-19, and 14 events for recapture. Considering the ten species that inhabit the study area, our study showed that four species: Astyanax janeiroensis, Astyanax hastatus, Parotocinclus maculicauda and Pimelodella lateristriga, moved at least 6 000m in 60 days. The other six species did not present long distance movements, as they were recaptured in the same site 90 days after being marked. For short distance study, movement data were obtained in one mark-recapture experiment held in a 100m long site subdivided into five 20m stretches where fishes were marked with different elastomer colours. We marked 583 specimens that after recapture showed two groups of different movement patterns. The first group was called "Long Movement Group" and the second one was called "Short Movement Group". The Long Movement Group showed, on average, 89.8% of moving fishes and 10.2% of non moving fishes, against 21.3% and 78.7%, respectively, for the Short Movement Group. It was concluded that fish movement could explain

  17. Environmental context explains Lévy and Brownian movement patterns of marine predators.

    PubMed

    Humphries, Nicolas E; Queiroz, Nuno; Dyer, Jennifer R M; Pade, Nicolas G; Musyl, Michael K; Schaefer, Kurt M; Fuller, Daniel W; Brunnschweiler, Juerg M; Doyle, Thomas K; Houghton, Jonathan D R; Hays, Graeme C; Jones, Catherine S; Noble, Leslie R; Wearmouth, Victoria J; Southall, Emily J; Sims, David W

    2010-06-24

    An optimal search theory, the so-called Lévy-flight foraging hypothesis, predicts that predators should adopt search strategies known as Lévy flights where prey is sparse and distributed unpredictably, but that Brownian movement is sufficiently efficient for locating abundant prey. Empirical studies have generated controversy because the accuracy of statistical methods that have been used to identify Lévy behaviour has recently been questioned. Consequently, whether foragers exhibit Lévy flights in the wild remains unclear. Crucially, moreover, it has not been tested whether observed movement patterns across natural landscapes having different expected resource distributions conform to the theory's central predictions. Here we use maximum-likelihood methods to test for Lévy patterns in relation to environmental gradients in the largest animal movement data set assembled for this purpose. Strong support was found for Lévy search patterns across 14 species of open-ocean predatory fish (sharks, tuna, billfish and ocean sunfish), with some individuals switching between Lévy and Brownian movement as they traversed different habitat types. We tested the spatial occurrence of these two principal patterns and found Lévy behaviour to be associated with less productive waters (sparser prey) and Brownian movements to be associated with productive shelf or convergence-front habitats (abundant prey). These results are consistent with the Lévy-flight foraging hypothesis, supporting the contention that organism search strategies naturally evolved in such a way that they exploit optimal Lévy patterns.

  18. Exhaled Aerosol Pattern Discloses Lung Structural Abnormality: A Sensitivity Study Using Computational Modeling and Fractal Analysis

    PubMed Central

    Xi, Jinxiang; Si, Xiuhua A.; Kim, JongWon; Mckee, Edward; Lin, En-Bing

    2014-01-01

    Background Exhaled aerosol patterns, also called aerosol fingerprints, provide clues to the health of the lung and can be used to detect disease-modified airway structures. The key is how to decode the exhaled aerosol fingerprints and retrieve the lung structural information for a non-invasive identification of respiratory diseases. Objective and Methods In this study, a CFD-fractal analysis method was developed to quantify exhaled aerosol fingerprints and applied it to one benign and three malign conditions: a tracheal carina tumor, a bronchial tumor, and asthma. Respirations of tracer aerosols of 1 µm at a flow rate of 30 L/min were simulated, with exhaled distributions recorded at the mouth. Large eddy simulations and a Lagrangian tracking approach were used to simulate respiratory airflows and aerosol dynamics. Aerosol morphometric measures such as concentration disparity, spatial distributions, and fractal analysis were applied to distinguish various exhaled aerosol patterns. Findings Utilizing physiology-based modeling, we demonstrated substantial differences in exhaled aerosol distributions among normal and pathological airways, which were suggestive of the disease location and extent. With fractal analysis, we also demonstrated that exhaled aerosol patterns exhibited fractal behavior in both the entire image and selected regions of interest. Each exhaled aerosol fingerprint exhibited distinct pattern parameters such as spatial probability, fractal dimension, lacunarity, and multifractal spectrum. Furthermore, a correlation of the diseased location and exhaled aerosol spatial distribution was established for asthma. Conclusion Aerosol-fingerprint-based breath tests disclose clues about the site and severity of lung diseases and appear to be sensitive enough to be a practical tool for diagnosis and prognosis of respiratory diseases with structural abnormalities. PMID:25105680

  19. The use of census migration data to approximate human movement patterns across temporal scales.

    PubMed

    Wesolowski, Amy; Buckee, Caroline O; Pindolia, Deepa K; Eagle, Nathan; Smith, David L; Garcia, Andres J; Tatem, Andrew J

    2013-01-01

    Human movement plays a key role in economies and development, the delivery of services, and the spread of infectious diseases. However, it remains poorly quantified partly because reliable data are often lacking, particularly for low-income countries. The most widely available are migration data from human population censuses, which provide valuable information on relatively long timescale relocations across countries, but do not capture the shorter-scale patterns, trips less than a year, that make up the bulk of human movement. Census-derived migration data may provide valuable proxies for shorter-term movements however, as substantial migration between regions can be indicative of well connected places exhibiting high levels of movement at finer time scales, but this has never been examined in detail. Here, an extensive mobile phone usage data set for Kenya was processed to extract movements between counties in 2009 on weekly, monthly, and annual time scales and compared to data on change in residence from the national census conducted during the same time period. We find that the relative ordering across Kenyan counties for incoming, outgoing and between-county movements shows strong correlations. Moreover, the distributions of trip durations from both sources of data are similar, and a spatial interaction model fit to the data reveals the relationships of different parameters over a range of movement time scales. Significant relationships between census migration data and fine temporal scale movement patterns exist, and results suggest that census data can be used to approximate certain features of movement patterns across multiple temporal scales, extending the utility of census-derived migration data.

  20. Seasonal movement, residency, and migratory patterns of Wilson's Snipe (Gallinago delicata)

    USGS Publications Warehouse

    Cline, Brittany B.; Haig, Susan M.

    2011-01-01

    Cross-seasonal studies of avian movement establish links between geographically distinct wintering, breeding, and migratory stopover locations, or assess site fidelity and movement between distinct phases of the annual cycle. Far fewer studies have investigated individual movement patterns within and among seasons over an annual cycle. Within western Oregon's Willamette Valley throughout 2007, we quantified intra- and interseasonal movement patterns, fidelity (regional and local), and migratory patterns of 37 radiomarked Wilson's Snipe (Gallinago delicata) to elucidate residency in a region of breeding- and wintering-range overlap. Telemetry revealed complex regional population structure, including winter residents (74%), winter transients (14%), summer residents (9%), and one year-round resident breeder (3%). Results indicated a lack of connectivity between winter and summer capture populations, some evidence of partial migration, and between-season fidelity to the region (winter-resident return; subsequent fall). Across seasons, the extent of movements and use of multiple wetland sites suggested that Wilson's Snipe were capable of exploratory movements but more regularly perceived local and fine-scale segments of the landscape as connected. Movements differed significantly by season and residency; individuals exhibited contracted movements during late winter and more expansive movements during precipitation-limited periods (late spring, summer, fall). Mean home-range size was 3.5& plusmn; 0.93 km2 (100% minimum convex polygon [MCP]) and 1.6 ± 0.42 km2 (95% fixed kernel) and did not vary by sex; however, home range varied markedly by season (range of 100% MCPs: 1.04-7.56 km2). The results highlight the need to consider seasonal and interspecific differences in shorebird life histories and space-use requirements when developing regional wetland conservation plans.

  1. Eye Movement Patterns of the Elderly during Stair Descent:Effect of Illumination

    NASA Astrophysics Data System (ADS)

    Kasahara, Satoko; Okabe, Sonoko; Nakazato, Naoko; Ohno, Yuko

    The relationship between the eye movement pattern during stair descent and illumination was studied in 4 elderly people in comparison with that in 5 young people. The illumination condition was light (85.0±30.9 lx) or dark (0.7±0.3 lx), and data of eye movements were obtained using an eye mark recorder. A flight of 15 steps was used for the experiment, and data on 3 steps in the middle, on which the descent movements were stabilized, were analyzed. The elderly subjects pointed their eyes mostly directly in front in the facial direction regardless of the illumination condition, but the young subjects tended to look down under the light condition. The young subjects are considered to have confirmed the safety of the front by peripheral vision, checked the stepping surface by central vision, and still maintained the upright position without leaning forward during stair descent. The elderly subjects, in contrast, always looked at the visual target by central vision even under the light condition and leaned forward. The range of eye movements was larger vertically than horizontally in both groups, and a characteristic eye movement pattern of repeating a vertical shuttle movement synchronous with descent of each step was observed. Under the dark condition, the young subjects widened the range of vertical eye movements and reduced duration of fixation. The elderly subjects showed no change in the range of eye movements but increased duration of fixation during stair descent. These differences in the eye movements are considered to be compensatory reactions to narrowing of the vertical visual field, reduced dark adaptation, and reduced dynamic visual acuity due to aging. These characteristics of eye movements of the elderly lead to an anteriorly leaned posture and lack of attention to the front during stair descent.

  2. School’s Out: Seasonal Variation in the Movement Patterns of School Children

    PubMed Central

    Kucharski, Adam J.; Conlan, Andrew J. K.; Eames, Ken T. D.

    2015-01-01

    School children are core groups in the transmission of many common infectious diseases, and are likely to play a key role in the spatial dispersal of disease across multiple scales. However, there is currently little detailed information about the spatial movements of this epidemiologically important age group. To address this knowledge gap, we collaborated with eight secondary schools to conduct a survey of movement patterns of school pupils in primary and secondary schools in the United Kingdom. We found evidence of a significant change in behaviour between term time and holidays, with term time weekdays characterised by predominately local movements, and holidays seeing much broader variation in travel patterns. Studies that use mathematical models to examine epidemic transmission and control often use adult commuting data as a proxy for population movements. We show that while these data share some features with the movement patterns reported by school children, there are some crucial differences between the movements of children and adult commuters during both term-time and holidays. PMID:26030611

  3. School's Out: Seasonal Variation in the Movement Patterns of School Children.

    PubMed

    Kucharski, Adam J; Conlan, Andrew J K; Eames, Ken T D

    2015-01-01

    School children are core groups in the transmission of many common infectious diseases, and are likely to play a key role in the spatial dispersal of disease across multiple scales. However, there is currently little detailed information about the spatial movements of this epidemiologically important age group. To address this knowledge gap, we collaborated with eight secondary schools to conduct a survey of movement patterns of school pupils in primary and secondary schools in the United Kingdom. We found evidence of a significant change in behaviour between term time and holidays, with term time weekdays characterised by predominately local movements, and holidays seeing much broader variation in travel patterns. Studies that use mathematical models to examine epidemic transmission and control often use adult commuting data as a proxy for population movements. We show that while these data share some features with the movement patterns reported by school children, there are some crucial differences between the movements of children and adult commuters during both term-time and holidays.

  4. Effects of landscape structure on movement patterns of the flightless bush cricket Pholidoptera griseoaptera.

    PubMed

    Diekötter, Tim; Speelmans, Marjan; Dusoulier, François; Van Wingerden, Walter K R E; Malfait, Jean-Pierre; Crist, Thomas O; Edwards, Peter J; Dietz, Hansjörg

    2007-02-01

    Because the viability of a population may depend on whether individuals can disperse, it is important for conservation planning to understand how landscape structure affects movement behavior. Some species occur in a wide range of landscapes differing greatly in structure, and the question arises of whether these species are particularly versatile in their dispersal or whether they are composed of genetically distinct populations adapted to contrasting landscapes. We performed a capture-mark-resight experiment to study movement patterns of the flightless bush cricket Pholidoptera griseoaptera (De Geer 1773) in two contrasting agricultural landscapes in France and Switzerland. The mean daily movement of P. griseoaptera was significantly higher in the landscape with patchily distributed habitat (Switzerland) than in the landscape with greater habitat connectivity (France). Net displacement rate did not differ between the two landscapes, which we attributed to the presence of more linear elements in the connected landscape, resulting in a more directed pattern of movement by P. griseoaptera. Significant differences in the movement patterns between landscapes with contrasting structure suggest important effects of landscape structure on movement and dispersal success. The possibility of varying dispersal ability within the same species needs to be studied in more detail because this may provide important information for sustainable landscape planning aimed at maintaining viable metapopulations, especially in formerly well-connected landscapes.

  5. Lévy flight movement patterns in marine predators may derive from turbulence cues.

    PubMed

    Reynolds, A M

    2014-11-01

    The Lévy-flight foraging hypothesis states that because Lévy flights can optimize search efficiencies, natural selection should have led to adaptations for Lévy flight foraging. Some of the strongest evidence for this hypothesis has come from telemetry data for sharks, bony fish, sea turtles and penguins. Here, I show that the programming for these Lévy movement patterns does not need to be very sophisticated or clever on the predator's part, as these movement patterns would arise naturally if the predators change their direction of travel only after encountering patches of relatively strong turbulence (a seemingly natural response to buffeting). This is established with the aid of kinematic simulations of three-dimensional turbulence. Lévy flights movement patterns are predicted to arise in all but the most quiescent of oceanic waters. PMID:25383027

  6. Lévy flight movement patterns in marine predators may derive from turbulence cues

    PubMed Central

    Reynolds, A. M.

    2014-01-01

    The Lévy-flight foraging hypothesis states that because Lévy flights can optimize search efficiencies, natural selection should have led to adaptations for Lévy flight foraging. Some of the strongest evidence for this hypothesis has come from telemetry data for sharks, bony fish, sea turtles and penguins. Here, I show that the programming for these Lévy movement patterns does not need to be very sophisticated or clever on the predator's part, as these movement patterns would arise naturally if the predators change their direction of travel only after encountering patches of relatively strong turbulence (a seemingly natural response to buffeting). This is established with the aid of kinematic simulations of three-dimensional turbulence. Lévy flights movement patterns are predicted to arise in all but the most quiescent of oceanic waters. PMID:25383027

  7. A gait paradigm reveals different patterns of abnormal cerebellar motor learning in primary focal dystonias.

    PubMed

    Hoffland, B S; Veugen, L C; Janssen, M M H P; Pasman, J W; Weerdesteyn, V; van de Warrenburg, B P

    2014-12-01

    Accumulating evidence points to a role of the cerebellum in the pathophysiology of primary dystonia. The aim of this study was to investigate whether the abnormalities of cerebellar motor learning in primary dystonia are solely detectable in more pure forms of cerebellum-dependent associative motor learning paradigms, or whether these are also present in other motor learning paradigms that rely heavily on the cerebellum but in addition require a more widespread sensorimotor network. Twenty-six patients with various forms of focal dystonia and 10 age-matched healthy controls participated in a motor learning paradigm on a split-belt treadmill. By using reflective markers, three-dimensional kinematics were recorded using a 6-camera motion analysis system. Adaptation walking parameters were analyzed offline, comparing the different dystonia groups and healthy controls. Patients with blepharospasm and writer's cramp were significantly impaired on various adaptation walking parameters. Whereas results of cervical dystonia patients did not differ from healthy controls in terms of adaptation walking parameters, differences in parameters of normal gait were found. We have here demonstrated abnormal sensorimotor adaptation with the split-belt paradigm in patients with blepharospasm and writer's cramp. This reinforces the current concept of cerebellar dysfunction in primary dystonia, and that this extends beyond more pure forms of cerebellum-dependent associative motor learning paradigms. However, the finding of normal adaptation in cervical dystonia patients indicates that the pattern of cerebellar dysfunction may be slightly different for the various forms of primary focal dystonia, suggesting that actual cerebellar pathology may not be a primary driving force in dystonia.

  8. Biogeographic response to Carboniferous place movements: marine and terrestrial patterns

    SciTech Connect

    Raymond, A.; Lutken, C.B.; Kelley, P.H.

    1985-01-01

    At the beginning of the Lower Carboniferous, east-west equatorial oceans and epicontinental seas circled the globe. By the end of the period, the collision of Laurussia and Gondwana split this equatorial ocean. The warm circum-equatorial current was deflected to the north and south along the east coast of the new landmass. This deflection could have had either of two effects: 1) climatic warming in the middle and high paleolatitudes; or 2) global cooling when warm currents became refrigerated in polar regions. The distribution of Lower Carboniferous plants and brachiopods suggests that the deflection of equatorial currents caused climatic warming. Early in the period, middle paleolatitudes and equatorial paleolatitudes each have distinctive palynomorph and plant macrofossil assemblages. This distinction disappears in the late Visean-earliest Namurian. All plant macrofossil genera that change range between the middle Visean and the late Visean-earliest Namurian move north, from low to high paleolatitudes. Brachiopod migrations had generic diversity fluctuations suggest that climatic warming occurred between the middle and late Visean. In the Tournaisian northern hemisphere, northward and southward migrations are approximately equal. Between the middle and late Visean, nearly all migrations represent expansion of range to the north. Northward and southward migrations between the late Visean and the earliest Namurian are again balanced. The late Visean was a time of taxonomic turnover, marked by increased origination and extinction rates, linked to the reorganization of climatic patterns.

  9. Muscle activity patterns during quick increase of movement amplitude in rapid elbow extensions.

    PubMed

    Takatoku, Nozomi; Fujiwara, Motoko

    2010-04-01

    In this study, we investigated a motor strategy for increasing the amplitude of movement in rapid extensions at the elbow joint. This study focused on the changes in a triphasic electromyographic (EMG) pattern, i.e., the first agonist burst (AG1), the second agonist burst (AG2) and the antagonist burst (ANT), for increasing the amplitude of movement required after the initiation of movement. Subjects performed 40 degrees (Basic task) and 80 degrees of extension (Wide task). These tasks were performed under two conditions; performing a predetermined task (SF condition) and performing a task in response to a visual stimulus immediately after movement commencement (ST condition). Kinematic parameters and EMG activity from the agonist (triceps brachii) and the antagonist (biceps brachii) muscles were recorded. As a result, the onset latency of AG1 and AG2 and the duration of AG1 were longer under the ST condition than the SF condition. No difference was observed between the SF and ST condition with respect to ANT activity. It is concluded that the motor strategy for increasing the amplitude of movement after the initiation of movement was to control the movement velocity and the timing to stop movement by the coactivation duration of AG1 and ANT and to stop the desired position accurately by AG2 activity.

  10. CUE: counterfeit-resistant usable eye movement-based authentication via oculomotor plant characteristics and complex eye movement patterns

    NASA Astrophysics Data System (ADS)

    Komogortsev, Oleg V.; Karpov, Alexey; Holland, Corey D.

    2012-06-01

    The widespread use of computers throughout modern society introduces the necessity for usable and counterfeit-resistant authentication methods to ensure secure access to personal resources such as bank accounts, e-mail, and social media. Current authentication methods require tedious memorization of lengthy pass phrases, are often prone to shouldersurfing, and may be easily replicated (either by counterfeiting parts of the human body or by guessing an authentication token based on readily available information). This paper describes preliminary work toward a counterfeit-resistant usable eye movement-based (CUE) authentication method. CUE does not require any passwords (improving the memorability aspect of the authentication system), and aims to provide high resistance to spoofing and shoulder-surfing by employing the combined biometric capabilities of two behavioral biometric traits: 1) oculomotor plant characteristics (OPC) which represent the internal, non-visible, anatomical structure of the eye; 2) complex eye movement patterns (CEM) which represent the strategies employed by the brain to guide visual attention. Both OPC and CEM are extracted from the eye movement signal provided by an eye tracking system. Preliminary results indicate that the fusion of OPC and CEM traits is capable of providing a 30% reduction in authentication error when compared to the authentication accuracy of individual traits.

  11. Generalized Pareto for Pattern-Oriented Random Walk Modelling of Organisms' Movements.

    PubMed

    Bertrand, Sophie; Joo, Rocío; Fablet, Ronan

    2015-01-01

    How organisms move and disperse is crucial to understand how population dynamics relates to the spatial heterogeneity of the environment. Random walk (RW) models are typical tools to describe movement patterns. Whether Lévy or alternative RW better describes forager movements is keenly debated. We get around this issue using the Generalized Pareto Distribution (GPD). GPD includes as specific cases Normal, exponential and power law distributions, which underlie Brownian, Poisson-like and Lévy walks respectively. Whereas previous studies typically confronted a limited set of candidate models, GPD lets the most likely RW model emerge from the data. We illustrate the wide applicability of the method using GPS-tracked seabird foraging movements and fishing vessel movements tracked by Vessel Monitoring System (VMS), both collected in the Peruvian pelagic ecosystem. The two parameters from the fitted GPD, a scale and a shape parameter, provide a synoptic characterization of the observed movement in terms of characteristic scale and diffusive property. They reveal and quantify the variability, among species and individuals, of the spatial strategies selected by predators foraging on a common prey field. The GPD parameters constitute relevant metrics for (1) providing a synthetic and pattern-oriented description of movement, (2) using top predators as ecosystem indicators and (3) studying the variability of spatial behaviour among species or among individuals with different personalities. PMID:26172045

  12. Generalized Pareto for Pattern-Oriented Random Walk Modelling of Organisms' Movements.

    PubMed

    Bertrand, Sophie; Joo, Rocío; Fablet, Ronan

    2015-01-01

    How organisms move and disperse is crucial to understand how population dynamics relates to the spatial heterogeneity of the environment. Random walk (RW) models are typical tools to describe movement patterns. Whether Lévy or alternative RW better describes forager movements is keenly debated. We get around this issue using the Generalized Pareto Distribution (GPD). GPD includes as specific cases Normal, exponential and power law distributions, which underlie Brownian, Poisson-like and Lévy walks respectively. Whereas previous studies typically confronted a limited set of candidate models, GPD lets the most likely RW model emerge from the data. We illustrate the wide applicability of the method using GPS-tracked seabird foraging movements and fishing vessel movements tracked by Vessel Monitoring System (VMS), both collected in the Peruvian pelagic ecosystem. The two parameters from the fitted GPD, a scale and a shape parameter, provide a synoptic characterization of the observed movement in terms of characteristic scale and diffusive property. They reveal and quantify the variability, among species and individuals, of the spatial strategies selected by predators foraging on a common prey field. The GPD parameters constitute relevant metrics for (1) providing a synthetic and pattern-oriented description of movement, (2) using top predators as ecosystem indicators and (3) studying the variability of spatial behaviour among species or among individuals with different personalities.

  13. Movement patterns and dispersal potential of Pecos bluntnose shiner (Notropis simus pecosensis) revealed using otolith microchemistry

    USGS Publications Warehouse

    Chase, Nathan M.; Caldwell, Colleen A.; Carleton, Scott A.; Gould, William R.; Hobbs, James A.

    2015-01-01

    Natal origin and dispersal potential of the federally threatened Pecos bluntnose shiner (Notropis simus pecosensis) were successfully characterized using otolith microchemistry and swimming performance trials. Strontium isotope ratios (87Sr:86Sr) of otoliths within the resident plains killifish (Fundulus zebrinus) were successfully used as a surrogate for strontium isotope ratios in water and revealed three isotopically distinct reaches throughout 297 km of the Pecos River, New Mexico, USA. Two different life history movement patterns were revealed in Pecos bluntnose shiner. Eggs and fry were either retained in upper river reaches or passively dispersed downriver followed by upriver movement during the first year of life, with some fish achieving a minimum movement of 56 km. Swimming ability of Pecos bluntnose shiner confirmed upper critical swimming speeds (Ucrit) as high as 43.8 cm·s−1 and 20.6 body lengths·s−1 in 30 days posthatch fish. Strong swimming ability early in life supports our observations of upriver movement using otolith microchemistry and confirms movement patterns that were previously unknown for the species. Understanding patterns of dispersal of this and other small-bodied fishes using otolith microchemistry may help redirect conservation and management efforts for Great Plains fishes.

  14. A relationship between eye movement patterns and performance in a precognitive tracking task

    NASA Technical Reports Server (NTRS)

    Repperger, D. W.; Hartzell, E. J.

    1977-01-01

    Eye movements made by various subjects in the performance of a precognitive tracking task are studied. The tracking task persented by an antiaircraft artillery (AAA) simulator has an input forcing function represented by a deterministic aircraft fly-by. The performance of subjects is ranked by two metrics. Good, mediocre, and poor trackers are selected for analysis based on performance during the difficult segment of the tracking task and over replications. Using phase planes to characterize both the eye movement patterns and the displayed error signal, a simple metric is developed to study these patterns. Two characterizations of eye movement strategies are defined and quantified. Using these two types of eye strategies, two conclusions are obtained about good, mediocre, and poor trackers. First, the eye tracker who used a fixed strategy will consistently perform better. Secondly, the best fixed strategy is defined as a Crosshair Fixator.

  15. Mechanical Force Alters Morphogenetic Movements and Segmental Gene Expression Patterns during Drosophila Embryogenesis

    PubMed Central

    Kumar, Abhishek; Shivashankar, G. V.

    2012-01-01

    The development of an organism is accompanied by various cellular morphogenetic movements, changes in cellular as well as nuclear morphology and transcription programs. Recent evidence suggests that intra and inter-cellular connections mediated by various adhesion proteins contribute to defining nuclear morphology. In addition, three dimensional organization of the cell nucleus regulate the transcription programs. However the link between cellular morphogenetic movements and its coupling to nuclear function in a developmental context is poorly understood. In this paper we use a point perturbation by tissue level laser ablation and sheet perturbation by application of force using magnetic tweezers to alter cellular morphogenetic movements and probe its impact on nuclear morphology and segmental gene expression patterns. Mechanical perturbations during blastoderm stage in a developing Drosophila embryo resulted in localized alterations in nuclear morphology and cellular movement. In addition, global defects in germ-band (GB) extension and retraction are observed when external force is applied during morphogenetic movements, suggesting a long-range physical coupling within the GB layer of cells. Further local application of force resulted in redistribution of non muscle myosin-II in the GB layer. Finally these perturbations lead to altered segmental gene (engrailed) expression patterns later during the development. Our observations suggest that there exists a tight regulation between nuclear morphology and cellular adhesive connections during morphogenetic movement of cells in the embryo. The observed spatial changes in patterning genes, with perturbation, highlight the importance of nuclear integrity to cellular movement in establishing gene expression program in a developmental system. PMID:22470437

  16. Quantitative analysis of bottlenose dolphin movement patterns and their relationship with foraging.

    PubMed

    Bailey, Helen; Thompson, Paul

    2006-03-01

    1. Broad-scale telemetry studies have greatly improved our understanding of the ranging patterns and habitat-use of many large vertebrates. However, there often remains considerable uncertainty over the function of different areas or the factors influencing habitat selection. Further insights into these processes can be obtained through analyses of finer scale movement patterns. For example, search behaviour may be modified in response to prey distribution and abundance. 2. In this study, quantitative analysis techniques are applied to the movements of bottlenose dolphins, recorded from land using a theodolite, to increase our understanding of their foraging strategies. Movements were modelled as a correlated random walk (CRW) and a biased random walk (BRW) to identify movement types and using a first-passage time (FPT) approach, which quantifies the time allocated to different areas and identifies the location and spatial scale of intensive search effort. 3. Only a quarter of the tracks were classed as CRW movement. Turning angle and directionality appeared to be key factors in determining the type of movement adopted. A high degree of overlap in search effort between separate movement paths indicated that there were small key sites (0.3 km radius) within the study area (4 km(2)). Foraging behaviour occurred mainly within these intensive search areas, indicating that they were feeding sites. 4. This approach provides a quantitative method of identifying important foraging areas and their spatial scale. Such techniques could be applied to movement paths for a variety of species derived from telemetry studies and increase our understanding of their foraging strategies.

  17. Inter-rater Reliability of Sustained Aberrant Movement Patterns as a Clinical Assessment of Muscular Fatigue

    PubMed Central

    Aerts, Frank; Carrier, Kathy; Alwood, Becky

    2016-01-01

    Background: The assessment of clinical manifestation of muscle fatigue is an effective procedure in establishing therapeutic exercise dose. Few studies have evaluated physical therapist reliability in establishing muscle fatigue through detection of changes in quality of movement patterns in a live setting. Objective: The purpose of this study is to evaluate the inter-rater reliability of physical therapists’ ability to detect altered movement patterns due to muscle fatigue. Design: A reliability study in a live setting with multiple raters. Participants: Forty-four healthy individuals (ages 19-35) were evaluated by six physical therapists in a live setting. Methods: Participants were evaluated by physical therapists for altered movement patterns during resisted shoulder rotation. Each participant completed a total of four tests: right shoulder internal rotation, right shoulder external rotation, left shoulder internal rotation and left shoulder external rotation. Results: For all tests combined, the inter-rater reliability for a single rater scoring ICC (2,1) was .65 (95%, .60, .71) This corresponds to moderate inter-rater reliability between physical therapists. Limitations: The results of this study apply only to healthy participants and therefore cannot be generalized to a symptomatic population. Conclusion: Moderate inter-rater reliability was found between physical therapists in establishing muscle fatigue through the observation of sustained altered movement patterns during dynamic resistive shoulder internal and external rotation. PMID:27347241

  18. Eye-Movement Patterns of Readers with Down Syndrome during Sentence-Processing: An Exploratory Study

    ERIC Educational Resources Information Center

    Frenck-Mestre, Cheryl; Zardan, Nathalie; Colas, Annie; Ghio, Alain

    2010-01-01

    Eye movements were examined to determine how readers with Down syndrome process sentences online. Participants were 9 individuals with Down syndrome ranging in reading level from Grades 1 to 3 and a reading-level-matched control group. For syntactically simple sentences, the pattern of reading times was similar for the two groups, with longer…

  19. Exploring the Eye-Movement Patterns as Chinese Children Read Texts: A Developmental Perspective

    ERIC Educational Resources Information Center

    Chen, Minglei; Ko, Hwawei

    2011-01-01

    This study was to investigate Chinese children's eye patterns while reading different text genres from a developmental perspective. Eye movements were recorded while children in the second through sixth grades read two expository texts and two narrative texts. Across passages, overall word frequency was not significantly different between the two…

  20. Patterns of auxin and abscisic acid movement in the tips of gravistimulated primary roots of maize.

    PubMed

    Young, L M; Evans, M L

    1996-01-01

    Because both abscisic acid (ABA) and auxin (IAA) have been suggested as possible chemical mediators of differential growth during root gravitropism, we compared with redistribution of label from applied 3H-IAA and 3H-ABA during maize root gravitropism and examined the relative basipetal movement of 3H-IAA and 3H-ABA applied to the caps of vertical roots. Lateral movement of 3H-ABA across the tips of vertical roots was non-polar and about 2-fold greater than lateral movement of 3H-IAA (also non-polar). The greater movement of ABA was not due to enhanced uptake since the uptake of 3H-IAA was greater than that of 3H-ABA. Basipetal movement of label from 3H-IAA or 3H-ABA applied to the root cap was determined by measuring radioactivity in successive 1 mm sections behind the tip 90 minutes after application. ABA remained largely in the first mm (point of application) whereas IAA was concentrated in the region 2-4 mm from the tip with substantial levels found 7-8 mm from the tip. Pretreatment with inhibitors of polar auxin transport decreased both gravicurvature and the basipetal movement of IAA. When roots were placed horizontally, the movement of 3H-IAA from top to bottom across the cap was enhanced relative to movement from bottom to top whereas the pattern of movement of label from 3H-ABA was unaffected. These results are consistent with the hypothesis that IAA plays a role in root gravitropism but contrary to the idea that gravi-induced asymmetric distribution of ABA contributes to the response. PMID:11540494

  1. Patterns of auxin and abscisic acid movement in the tips of gravistimulated primary roots of maize

    NASA Technical Reports Server (NTRS)

    Young, L. M.; Evans, M. L.

    1996-01-01

    Because both abscisic acid (ABA) and auxin (IAA) have been suggested as possible chemical mediators of differential growth during root gravitropism, we compared with redistribution of label from applied 3H-IAA and 3H-ABA during maize root gravitropism and examined the relative basipetal movement of 3H-IAA and 3H-ABA applied to the caps of vertical roots. Lateral movement of 3H-ABA across the tips of vertical roots was non-polar and about 2-fold greater than lateral movement of 3H-IAA (also non-polar). The greater movement of ABA was not due to enhanced uptake since the uptake of 3H-IAA was greater than that of 3H-ABA. Basipetal movement of label from 3H-IAA or 3H-ABA applied to the root cap was determined by measuring radioactivity in successive 1 mm sections behind the tip 90 minutes after application. ABA remained largely in the first mm (point of application) whereas IAA was concentrated in the region 2-4 mm from the tip with substantial levels found 7-8 mm from the tip. Pretreatment with inhibitors of polar auxin transport decreased both gravicurvature and the basipetal movement of IAA. When roots were placed horizontally, the movement of 3H-IAA from top to bottom across the cap was enhanced relative to movement from bottom to top whereas the pattern of movement of label from 3H-ABA was unaffected. These results are consistent with the hypothesis that IAA plays a role in root gravitropism but contrary to the idea that gravi-induced asymmetric distribution of ABA contributes to the response.

  2. Activity patterns of the diaphragm during voluntary movements in awake cats.

    PubMed

    Uga, Minako; Niwa, Masatoshi; Ochiai, Naoyuki; Sasaki, Sei-Ichi

    2010-05-01

    The diaphragm is an important inspiratory muscle, and is also known to participate in the postural function. However, the activity of the diaphragm during voluntary movements has not been fully investigated in awake animals. In order to investigate the diaphragmatic activity during voluntary movements such as extending or rotating their body, we analyzed the electromyogram (EMG) of the diaphragm and trunk muscles in the cat using a technique for simultaneous recordings of EMG signals and video images. Periodic respiratory discharges occurred in the left and right costal diaphragm when the cat kept still. However, once the cat moved, their periodicity and/or synchrony were sometimes buried by non-respiratory activity. Such non-periodic diaphragmatic activities during voluntary movements are considered as the combination of respiratory activity and non-respiratory activity. Most of the diaphragmatic activities started shortly after the initiation of standing-up movements and occurred after the onset of trunk muscle activities. Those activities were more active compared to the normal respiratory activity. During rotation movements, left and right diaphragmatic activities showed asymmetrical discharge patterns and higher discharges than those during the resting situation. This asymmetrical activity may be caused by taking different lengths of each side of the diaphragm and trunk muscles. During reaching movements, the diaphragmatic activity occurred prior to or with the onset of trunk muscle activities. It is likely that diaphragmatic activities during reaching movements and standing-up movements may have been controlled by some different control mechanisms of the central nervous system. This study will suggest that the diaphragmatic activity is regulated not only by the respiratory center but also by inputs from the center for voluntary movements and/or sensory reflex pathways under the awake condition.

  3. Scale-dependent hierarchical adjustments of movement patterns in a long-range foraging seabird.

    PubMed Central

    Fritz, Hervé; Said, Sonia; Weimerskirch, Henri

    2003-01-01

    Foraging animals are expected to adjust their path according to the hierarchical spatial distribution of food resources and environmental factors. Studying such behaviour requires methods that allow for the detection of changes in pathways' characteristics across scales, i.e. a definition of scale boundaries and techniques to continuously monitor the precise movement of the animal over a sufficiently long period. We used a recently developed application of fractals, the changes in fractal dimension within a path and applied it to foraging trips over scales ranging across five orders of magnitude (10 m to 1000 km), using locations of wandering albatrosses (Diomedea exulans) recorded at 1 s intervals with a miniaturized global positioning system. Remarkably, all animals consistently showed the same pattern: the use of three scale-dependent nested domains where they adjust tortuosity to different environmental and behavioural constraints. At a small scale (ca. 100 m) they use a zigzag movement as they continuously adjust for optimal use of wind; at a medium scale (1-10 km), the movement shows changes in tortuosity consistent with food-searching behaviour; and at a large scale (greater than 10 km) the movement corresponds to commuting between patches and is probably influenced by large-scale weather systems. Our results demonstrate the possibility of identifying the hierarchical spatial scales at which long-ranging animals adjust their foraging behaviour, even in featureless environments such as oceans, and hence how to relate their movement patterns to environmental factors using an objective mathematical approach. PMID:12816652

  4. A novel pattern of leaf movement: the case of Capparis spinosa L.

    PubMed

    Levizou, Efi; Kyparissis, Aris

    2016-09-01

    A novel type of heliotropic leaf movement is presented for Capparis spinosa L., a summer perennial shrub of Mediterranean and arid ecosystems. In contrast to plants that demonstrate uniform diaheliotropic and/or paraheliotropic movement for all their foliage, the alternate leaves of C. spinosa follow different movement patterns according to their stem azimuth and the side of the stem that they come from (cluster). Additionally, leaf movement for each cluster may not be uniform throughout the day, showing diaheliotropic characteristics during half of the day and paraheliotropic characteristics during the rest of the day. In an attempt to reveal the adaptive significance of this differential movement pattern, the following hypotheses were tested: (i) increase of the intercepted solar radiation and photosynthesis, (ii) avoidance of photoinhibitory conditions, (iii) amelioration of water-use efficiency and (iv) adjustment of the leaf temperature microenvironment. No evidence was found in support of the first two hypotheses. A slight difference toward a better water use was found for the moving compared with immobilized leaves, in combination with a better cooling effect. PMID:27406206

  5. Scale-dependent hierarchical adjustments of movement patterns in a long-range foraging seabird.

    PubMed

    Fritz, Hervé; Said, Sonia; Weimerskirch, Henri

    2003-06-01

    Foraging animals are expected to adjust their path according to the hierarchical spatial distribution of food resources and environmental factors. Studying such behaviour requires methods that allow for the detection of changes in pathways' characteristics across scales, i.e. a definition of scale boundaries and techniques to continuously monitor the precise movement of the animal over a sufficiently long period. We used a recently developed application of fractals, the changes in fractal dimension within a path and applied it to foraging trips over scales ranging across five orders of magnitude (10 m to 1000 km), using locations of wandering albatrosses (Diomedea exulans) recorded at 1 s intervals with a miniaturized global positioning system. Remarkably, all animals consistently showed the same pattern: the use of three scale-dependent nested domains where they adjust tortuosity to different environmental and behavioural constraints. At a small scale (ca. 100 m) they use a zigzag movement as they continuously adjust for optimal use of wind; at a medium scale (1-10 km), the movement shows changes in tortuosity consistent with food-searching behaviour; and at a large scale (greater than 10 km) the movement corresponds to commuting between patches and is probably influenced by large-scale weather systems. Our results demonstrate the possibility of identifying the hierarchical spatial scales at which long-ranging animals adjust their foraging behaviour, even in featureless environments such as oceans, and hence how to relate their movement patterns to environmental factors using an objective mathematical approach. PMID:12816652

  6. A novel pattern of leaf movement: the case of Capparis spinosa L.

    PubMed

    Levizou, Efi; Kyparissis, Aris

    2016-09-01

    A novel type of heliotropic leaf movement is presented for Capparis spinosa L., a summer perennial shrub of Mediterranean and arid ecosystems. In contrast to plants that demonstrate uniform diaheliotropic and/or paraheliotropic movement for all their foliage, the alternate leaves of C. spinosa follow different movement patterns according to their stem azimuth and the side of the stem that they come from (cluster). Additionally, leaf movement for each cluster may not be uniform throughout the day, showing diaheliotropic characteristics during half of the day and paraheliotropic characteristics during the rest of the day. In an attempt to reveal the adaptive significance of this differential movement pattern, the following hypotheses were tested: (i) increase of the intercepted solar radiation and photosynthesis, (ii) avoidance of photoinhibitory conditions, (iii) amelioration of water-use efficiency and (iv) adjustment of the leaf temperature microenvironment. No evidence was found in support of the first two hypotheses. A slight difference toward a better water use was found for the moving compared with immobilized leaves, in combination with a better cooling effect.

  7. Movement and ranging patterns of the Common Chaffinch in heterogeneous forest landscapes

    PubMed Central

    Kubiczek, Katrin; Böhm, Stefan M.; Wells, Konstans

    2014-01-01

    The partitioning of production forests into discretely managed forest stands confronts animals with diversity in forest attributes at scales from point-level tree assemblages to distinct forest patches and range-level forest cover. We have investigated the movement and ranging patterns of male Common Chaffinches, Fringilla coelebs, in heterogeneous forest production landscapes during spring and summer in south-western Germany. We radio-tracked a total of 15 adult males, each for up to six days, recording locations at 10-min intervals. We then performed point-level tree surveys at all tracking locations and classified forest stand attributes for the areal covering of birds’ ranges. Movement distances were shortest in beech forest stands and longer in spruce-mixed and non-spruce conifer stands. Movement distances increased with stand age in beech stands but not in others, an effect that was only detectable in a multilevel hierarchical model. We found negligible effects of point-level tree assemblages and temperature on movement distances. Daily range estimates were from 0.01 to 8.0 hectare (median of 0.86 ha) with no evident impact of forest attributes on ranging patterns but considerable intra-individual variation in range sizes over consecutive days. Most daily ranges covered more than one forest stand type. Our results show that forest management impacts the movement behaviour of chaffinches in heterogeneous production forest. Although point-level effects of movement distances are weak compared with stand-level effects in this study, the hierarchical organization of forest is an important aspect to consider when analysing fine-scale movement and might exert more differentiated effects on bird species that are more sensitive to habitat changes than the chaffinch. PMID:25024900

  8. Analysis of radionuclide concentrations and movement patterns of Hanford-site mule deer

    SciTech Connect

    Eberhardt, L.E.; Hanson, E.E.; Cadwell, L.L.

    1982-10-01

    From 1980 through 1982, the movements of 37 radio-collared mule deer (Odocoileus hemionus) were monitored for periods of 3 to 17 months on the Handord Site in southcentral Washington. The objectives were to compare radionuclide concentrations in deer residing near the 200 Area waste management sites with concentrations in deer occupying areas remote from waste management sites and to document movement patterns of Hanford Site deer with particular emphasis on offsite movements. Cesium-137 in deer muscle and liver and /sup 90/Sr concentrations in deer bone were statistically higher in deer living near the 200 Area than in control animals. During this study, the highest concentrations of /sup 137/Cs and /sup 90/Sr in 200 Area deer were in those individuals residing in or immediately adjacent to radiation zones. Cesium-137 and /sup 90/Sr concentrations were more variable in deer residing near the 200 Area than in control animals, where only background (fallout) levels were observed. Movement patterns of Hanford site deer were analyzed to determine home range size and usage. The average home range was 0.39 +- 27 km/sup 2/. In addition, ten (27%) of the monitored deer made offsite movements during the study period. While most of these movements were made in the spring and summer, some fall and winter movements were noted. It was estimated that approximately 8% (95% confidence interval is from 0 to 21%) of the Hanford deer herd is harvested each year. As a result of the low harvest rate, the Hanford deer herd appears to have a disproportionate number of older animals, with 24% of the 17 examined deer older than 10.5 years.

  9. Lateralization patterns of covert but not overt movements change with age: An EEG neurofeedback study.

    PubMed

    Zich, Catharina; Debener, Stefan; De Vos, Maarten; Frerichs, Stella; Maurer, Stefanie; Kranczioch, Cornelia

    2015-08-01

    The mental practice of movements has been suggested as a promising add-on therapy to facilitate motor recovery after stroke. In the case of mentally practised movements, electroencephalogram (EEG) can be utilized to provide feedback about an otherwise covert act. The main target group for such an intervention are elderly patients, though research so far is largely focused on young populations (<30 years). The present study therefore aimed to examine the influence of age on the neural correlates of covert movements (CMs) in a real-time EEG neurofeedback framework. CM-induced event-related desynchronization (ERD) was studied in young (mean age: 23.6 years) and elderly (mean age: 62.7 years) healthy adults. Participants performed covert and overt hand movements. CMs were based on kinesthetic motor imagery (MI) or quasi-movements (QM). Based on previous studies investigating QM in the mu frequency range (8-13Hz) QM were expected to result in more lateralized ERD% patterns and accordingly higher classification accuracies. Independent of CM strategy the elderly were characterized by a significantly reduced lateralization of ERD%, due to stronger ipsilateral ERD%, and in consequence, reduced classification accuracies. QM were generally perceived as more vivid, but no differences were evident between MI and QM in ERD% or classification accuracies. EEG feedback enhanced task-related activity independently of strategy and age. ERD% measures of overt and covert movements were strongly related in young adults, whereas in the elderly ERD% lateralization is dissociated. In summary, we did not find evidence in support of more pronounced ERD% lateralization patterns in QM. Our finding of a less lateralized activation pattern in the elderly is in accordance to previous research and with the idea that compensatory processes help to overcome neurodegenerative changes related to normal ageing. Importantly, it indicates that EEG neurofeedback studies should place more emphasis on the

  10. Path segmentation for beginners: an overview of current methods for detecting changes in animal movement patterns.

    PubMed

    Edelhoff, Hendrik; Signer, Johannes; Balkenhol, Niko

    2016-01-01

    Increased availability of high-resolution movement data has led to the development of numerous methods for studying changes in animal movement behavior. Path segmentation methods provide basics for detecting movement changes and the behavioral mechanisms driving them. However, available path segmentation methods differ vastly with respect to underlying statistical assumptions and output produced. Consequently, it is currently difficult for researchers new to path segmentation to gain an overview of the different methods, and choose one that is appropriate for their data and research questions. Here, we provide an overview of different methods for segmenting movement paths according to potential changes in underlying behavior. To structure our overview, we outline three broad types of research questions that are commonly addressed through path segmentation: 1) the quantitative description of movement patterns, 2) the detection of significant change-points, and 3) the identification of underlying processes or 'hidden states'. We discuss advantages and limitations of different approaches for addressing these research questions using path-level movement data, and present general guidelines for choosing methods based on data characteristics and questions. Our overview illustrates the large diversity of available path segmentation approaches, highlights the need for studies that compare the utility of different methods, and identifies opportunities for future developments in path-level data analysis.

  11. Generalized Pareto for Pattern-Oriented Random Walk Modelling of Organisms’ Movements

    PubMed Central

    Bertrand, Sophie; Joo, Rocío; Fablet, Ronan

    2015-01-01

    How organisms move and disperse is crucial to understand how population dynamics relates to the spatial heterogeneity of the environment. Random walk (RW) models are typical tools to describe movement patterns. Whether Lévy or alternative RW better describes forager movements is keenly debated. We get around this issue using the Generalized Pareto Distribution (GPD). GPD includes as specific cases Normal, exponential and power law distributions, which underlie Brownian, Poisson-like and Lévy walks respectively. Whereas previous studies typically confronted a limited set of candidate models, GPD lets the most likely RW model emerge from the data. We illustrate the wide applicability of the method using GPS-tracked seabird foraging movements and fishing vessel movements tracked by Vessel Monitoring System (VMS), both collected in the Peruvian pelagic ecosystem. The two parameters from the fitted GPD, a scale and a shape parameter, provide a synoptic characterization of the observed movement in terms of characteristic scale and diffusive property. They reveal and quantify the variability, among species and individuals, of the spatial strategies selected by predators foraging on a common prey field. The GPD parameters constitute relevant metrics for (1) providing a synthetic and pattern–oriented description of movement, (2) using top predators as ecosystem indicators and (3) studying the variability of spatial behaviour among species or among individuals with different personalities. PMID:26172045

  12. Path segmentation for beginners: an overview of current methods for detecting changes in animal movement patterns.

    PubMed

    Edelhoff, Hendrik; Signer, Johannes; Balkenhol, Niko

    2016-01-01

    Increased availability of high-resolution movement data has led to the development of numerous methods for studying changes in animal movement behavior. Path segmentation methods provide basics for detecting movement changes and the behavioral mechanisms driving them. However, available path segmentation methods differ vastly with respect to underlying statistical assumptions and output produced. Consequently, it is currently difficult for researchers new to path segmentation to gain an overview of the different methods, and choose one that is appropriate for their data and research questions. Here, we provide an overview of different methods for segmenting movement paths according to potential changes in underlying behavior. To structure our overview, we outline three broad types of research questions that are commonly addressed through path segmentation: 1) the quantitative description of movement patterns, 2) the detection of significant change-points, and 3) the identification of underlying processes or 'hidden states'. We discuss advantages and limitations of different approaches for addressing these research questions using path-level movement data, and present general guidelines for choosing methods based on data characteristics and questions. Our overview illustrates the large diversity of available path segmentation approaches, highlights the need for studies that compare the utility of different methods, and identifies opportunities for future developments in path-level data analysis. PMID:27595001

  13. Spatial distribution patterns and movements of Holothuria arguinensis in the Ria Formosa (Portugal)

    NASA Astrophysics Data System (ADS)

    Siegenthaler, Andjin; Cánovas, Fernando; González-Wangüemert, Mercedes

    2015-08-01

    Holothurian populations are under pressure worldwide because of increasing demand for beche-de-mer, mainly for Asian consumption. Importations to this area from new temperate fishing grounds provide economic opportunities but also raise concerns regarding future over-exploitation. Studies on the habitat preferences and movements of sea cucumbers are important for the management of sea cucumber stocks and sizing of no-take zones, but information on the ecology and behavior of temperate sea cucumbers is scarce. This study describes the small-scale distribution and movement patterns of Holothuria arguinensis in the intertidal zone of the Ria Formosa national park (Portugal). Mark/recapture studies were performed to record their movements over time on different habitats (sand and seagrass). H. arguinensis preferred seagrass habitats and did not show a size or life stage-related spatial segregation. Its density was 563 ind. ha- 1 and mean movement speed was 10 m per day. Movement speed did not differ between habitats and the direction of movement was offshore during the day and shoreward during the night. Median home range size was 35 m2 and overlap among home ranges was 84%. H. arguinensis' high abundance, close association with seagrass and easy catchability in the intertidal zone, indicate the importance of including intertidal lagoons in future studies on temperate sea cucumber ecology since those systems might require different management strategies than fully submerged habitats.

  14. In vitro analysis suggests that difference in cell movement during direct interaction can generate various pigment patterns in vivo.

    PubMed

    Yamanaka, Hiroaki; Kondo, Shigeru

    2014-02-01

    Pigment patterns of organisms have invoked strong interest from not only biologists but also, scientists in many other fields. Zebrafish is a useful model animal for studying the mechanism of pigment pattern formation. The zebrafish stripe pattern is primarily two types of pigment cells: melanophores and xanthophores. Previous studies have reported that interactions among these pigment cells are important for pattern formation. In the recent report, we found that the direct contact by xanthophores induces the membrane depolarization of melanophores. From analysis of jaguar mutants, it is suggested that the depolarization affects the movements of melanophores. To analyze the cell movement in detail, we established a unique in vitro system. It allowed us to find that WT xanthophores induced repulsive movement of melanophores through direct contact. The xanthophores also chased the melanophores. As a result, they showed run-and-chase movements. We also analyzed the cell movement of pigment cells from jaguar and leopard mutants, which have fuzzy stripes and spot patterns, respectively. jaguar cells showed inhibited run-and-chase movements, and leopard melanophores scarcely showed repulsive response. Furthermore, we paired mutant and WT cells and showed which of the melanophores and xanthophores have responsibility for the altered cell movements. These results suggested that there is a correspondence relationship between the cell movements and pigment patterns. The correspondence relationship highlighted the importance of the cell movements in the pattern formation and showed that our system is a quite useful system for future study in this field.

  15. Patterns of tongue and jaw movement in a cinefluorographic study of feeding in the macaque.

    PubMed

    Hiiemae, K M; Hayenga, S M; Reese, A

    1995-03-01

    feeding in macaques are more complex than those reported for non-primate mammals, as they change between successive jaw cycles. The changes observed during sequences, and between different foods, suggest that the effector systems involved are continuously modulated, and the jaw-movement profile during opening may be dependent on the pattern of tongue movement.

  16. [Somatosensory evoked potentials during natural and learned patterns of postural adjustment, accompanying limb movements in dogs].

    PubMed

    Gavrilenko, T; Frolov, A G; Ioffe, M E; Ganchev, G N; Aleksandrov, A V; Pavlova, O G

    2001-01-01

    A goal of the study was to investigate cortical reorganization corresponding to inhibition of innate motor patterns during motor learning. Functional changes in the sensorimotor cortex during learned rearrangement of the natural diagonal pattern of postural adjustment (PA) accompanying a hindlimb movement into a new one, the so-called unilateral pattern, were studied in dogs by testing somatosensory evoked potentials (SEP) in response to stimulation of a forelimb during PA immediately before the limb movement onset. During PA the latency and the amplitude of several SEP components decreased. In general, changes in SEP were less pronounced in the learned unilateral pattern of postural adjustment in comparison with the innate diagonal pattern, but the difference was significant only for some SEP components. The SEP late positivity in the learned postural pattern was replaced by a negativity. The SEP changes were similar independently of whether the test stimulus was applied on the forelimb loaded or unloaded during postural adjustment. The data suggest that changes in interrelations between different neuronal populations in the sensorimotor cortex during formation and realization of a learned motor program can be reflected in SEP changes.

  17. Dive and beak movement patterns in leatherback turtles Dermochelys coriacea during internesting intervals in French Guiana.

    PubMed

    Fossette, Sabrina; Gaspar, Philippe; Handrich, Yves; Le Maho, Yvon; Georges, Jean-Yves

    2008-03-01

    1. Investigating the foraging patterns of free-ranging species is essential to estimate energy/time budgets for assessing their real reproductive strategy. Leatherback turtles Dermochelys coriacea (Vandelli 1761), commonly considered as capital breeders, have been reported recently to prospect actively during the breeding season in French Guiana, Atlantic Ocean. In this study we investigate the possibility of this active behaviour being associated with foraging, by studying concurrently diving and beak movement patterns in gravid females equipped with IMASEN (Inter-MAndibular Angle SENsor). 2. Four turtles provided data for periods varying from 7.3 to 56.1 h while exhibiting continuous short and shallow benthic dives. Beak movement ('b-m') events occurred in 34% of the dives, on average 1.8 +/- 1.4 times per dive. These b-m events lasted between 1.5 and 20 s and occurred as isolated or grouped (two to five consecutive beak movements) events in 96.0 +/- 4.0% of the recorded cases, and to a lesser extent in series (> five consecutive beak movements). 3. Most b-m events occurred during wiggles at the bottom of U- and W-shaped dives and at the beginning and end of the bottom phase of the dives. W-shaped dives were associated most frequently with beak movements (65% of such dives) and in particular with grouped beak movements. 4. Previous studies proposed wiggles to be indicator of predatory activity, U- and W-shaped dives being putative foraging dives. Beak movements recorded in leatherbacks during the first hours of their internesting interval in French Guiana may be related to feeding attempts. 5. In French Guiana, leatherbacks show different mouth-opening patterns for different dive patterns, suggesting that they forage opportunistically on occasional prey, with up to 17% of the dives appearing to be successful feeding dives. 6. This study highlights the contrasted strategies adopted by gravid leatherbacks nesting on the Pacific coasts of Costa Rica, in the deep

  18. Characteristic visuomotor influences on eye-movement patterns to faces and other high level stimuli

    PubMed Central

    Arizpe, Joseph M.; Walsh, Vincent; Baker, Chris I.

    2015-01-01

    Eye-movement patterns are often utilized in studies of visual perception as indices of the specific information extracted to efficiently process a given stimulus during a given task. Our prior work, however, revealed that not only the stimulus and task influence eye-movements, but that visuomotor (start position) factors also robustly and characteristically influence eye-movement patterns to faces (Arizpe et al., 2012). Here we manipulated lateral starting side and distance from the midline of face and line-symmetrical control (butterfly) stimuli in order to further investigate the nature and generality of such visuomotor influences. First we found that increasing starting distance from midline (4°, 8°, 12°, and 16° visual angle) strongly and proportionately increased the distance of the first ordinal fixation from midline. We did not find influences of starting distance on subsequent fixations, however, suggesting that eye-movement plans are not strongly affected by starting distance following an initial orienting fixation. Further, we replicated our prior effect of starting side (left, right) to induce a spatially contralateral tendency of fixations after the first ordinal fixation. However, we also established that these visuomotor influences did not depend upon the predictability of the location of the upcoming stimulus, and were present not only for face stimuli but also for our control stimulus category (butterflies). We found a correspondence in overall left-lateralized fixation tendency between faces and butterflies. Finally, for faces, we found a relationship between left starting side (right sided fixation pattern tendency) and increased recognition performance, which likely reflects a cortical right hemisphere (left visual hemifield) advantage for face perception. These results further indicate the importance of considering and controlling for visuomotor influences in the design, analysis, and interpretation of eye-movement studies. PMID:26283982

  19. Classification of abnormal fundus autofluorescence patterns in the junctional zone of geographic atrophy in patients with age related macular degeneration

    PubMed Central

    Bindewald, A; Schmitz-Valckenberg, S; Jorzik, J J; Dolar-Szczasny, J; Sieber, H; Keilhauer, C; Weinberger, A W A; Dithmar, S; Pauleikhoff, D; Mansmann, U; Wolf, S; Holz, F G

    2005-01-01

    Aim: To describe and classify patterns of abnormal fundus autofluorescence (FAF) in the junctional zone of geographic atrophy (GA) in patients with age related macular degeneration. Methods: Digital FAF images were recorded in 164 eyes of 107 patients using a confocal scanning laser ophthalmoscope (cSLO; excitation 488 nm, detection above 500 nm) as part of a prospective multicentre natural history study (FAM Study). FAF images were obtained in accordance with a standardised protocol for digital image acquisition and generation of mean images after automated alignment. Results: Image quality was sufficient for classification of FAF patterns in 149 eyes (90.9%) with lens opacities being the most common reason for insufficient image quality. Abnormal FAF outside GA in 149 eyes was classified into four patterns: focal (12.1%), banded (12.8%), patchy (2.0%), and diffuse (57.0%), whereby 12.1% had normal background FAF in the junctional zone. In 4% there was no predominant pattern. The diffuse pattern was subdivided into four groups including reticular (4.7%), branching (27.5%), fine granular (18.1%), and fine granular with peripheral punctate spots (6.7%). Conclusions: Different phenotypic patterns of abnormal FAF in the junctional zone of GA can be identified with cSLO FAF imaging. These distinct patterns may reflect heterogeneity at a cellular and molecular level in contrast with a non-specific ageing process. A refined phenotypic classification may be helpful to identify prognostic determinants for the spread of atrophy and visual loss, for identification of genetic risk factors as well as for the design of future interventional trials. PMID:15965170

  20. Lateralization of brain activity pattern during unilateral movement in Parkinson's disease.

    PubMed

    Wu, Tao; Hou, Yanan; Hallett, Mark; Zhang, Jiarong; Chan, Piu

    2015-05-01

    We investigated the lateralization of brain activity pattern during performance of unilateral movement in drug-naïve Parkinson's disease (PD) patients with only right hemiparkinsonian symptoms. Functional MRI was obtained when the subjects performed strictly unilateral right hand movement. A laterality index was calculated to examine the lateralization. Patients had decreased activity in the left putamen and left supplementary motor area, but had increased activity in the right primary motor cortex, right premotor cortex, left postcentral gyrus, and bilateral cerebellum. The laterality index was significantly decreased in PD patients compared with controls (0.41 ± 0.14 vs. 0.84 ± 0.09). The connectivity from the left putamen to cortical motor regions and cerebellum was decreased, while the interactions between the cortical motor regions, cerebellum, and right putamen were increased. Our study demonstrates that in early PD, the lateralization of brain activity during unilateral movement is significantly reduced. The dysfunction of the striatum-cortical circuit, decreased transcallosal inhibition, and compensatory efforts from cortical motor regions, cerebellum, and the less affected striatum are likely reasons contributing to the reduced motor lateralization. The disruption of the lateralized brain activity pattern might be a reason underlying some motor deficits in PD, like mirror movements or impaired bilateral motor coordination. PMID:25644527

  1. Lateralization of brain activity pattern during unilateral movement in Parkinson's disease.

    PubMed

    Wu, Tao; Hou, Yanan; Hallett, Mark; Zhang, Jiarong; Chan, Piu

    2015-05-01

    We investigated the lateralization of brain activity pattern during performance of unilateral movement in drug-naïve Parkinson's disease (PD) patients with only right hemiparkinsonian symptoms. Functional MRI was obtained when the subjects performed strictly unilateral right hand movement. A laterality index was calculated to examine the lateralization. Patients had decreased activity in the left putamen and left supplementary motor area, but had increased activity in the right primary motor cortex, right premotor cortex, left postcentral gyrus, and bilateral cerebellum. The laterality index was significantly decreased in PD patients compared with controls (0.41 ± 0.14 vs. 0.84 ± 0.09). The connectivity from the left putamen to cortical motor regions and cerebellum was decreased, while the interactions between the cortical motor regions, cerebellum, and right putamen were increased. Our study demonstrates that in early PD, the lateralization of brain activity during unilateral movement is significantly reduced. The dysfunction of the striatum-cortical circuit, decreased transcallosal inhibition, and compensatory efforts from cortical motor regions, cerebellum, and the less affected striatum are likely reasons contributing to the reduced motor lateralization. The disruption of the lateralized brain activity pattern might be a reason underlying some motor deficits in PD, like mirror movements or impaired bilateral motor coordination.

  2. Patterns of movement for youth within an integrated continuum of residential services

    PubMed Central

    Huefner, Jonathan C.; James, Sigrid; Ringle, Jay; Thompson, Ronald W.; Daly, Daniel L.

    2013-01-01

    This study examined patterns of movement for youth receiving services within a continuum of intensive and restrictive residentially-based programs. Data were collected for 701 completed episodes of care within a three-program residential continuum of care over a 5 year period, and examined time within program, movement between programs, in-program disruptive behavior, and discharge status. Results showed that most youth either remained in a stable placement in the least restrictive of the programs, or followed a pattern of placements that systematically moved them from more restrictive to less restrictive settings. Of note, transitions from more restrictive to less restrictive programs correspond to deescalating levels of problem behavior; and over 80% of the youth were stepped down to either family-based or independent living situations at the time of departure. Findings support the notion that a continuum of intensive residential services can serve the needs of youth with significant emotional and behavioral needs. PMID:24273361

  3. Vertebral orientations and muscle activation patterns during controlled head movements in cats.

    PubMed

    Keshner, E A

    1994-01-01

    The focus of these experiments was to determine the relationships between head movement, neck muscle activation patterns, and the positions and movements of the cervical vertebrae. One standing cat and one prone cat were trained to produce voluntary sinusoidal movements of the head in the sagittal plane. Video-opaque markers were placed on the cervical vertebrae, and intramuscular patch electrodes implanted in four muscles of the head and neck. Cinefluoroscopic images of cervical vertebral motion and electromyographic responses were simultaneously recorded. Analysis of the spinal movement revealed that the two cats used different strategies to keep their heads aligned with the tracker. In the standing cat, vertebral motion described a more circular arc, compared to a forward diagonal in the prone cat. Intervertebral motion was limited, but more acute angles appeared between the vertebrae of the prone lying than of the standing animal. Data revealed that the central nervous system could control several axes of motion to keep the cervical spine matched to the moving stimulus. Phase relations between the sinusoidal motion of the vertebral column, peak activation of the neck muscles, and that of the stimulus were examined, and several different control strategies were observed both between and within animals. The results suggest that the central nervous system engages in multiple strategies of musculo-skeletal coordination to achieve a single movement outcome. PMID:8056075

  4. Lack of sex-specific movement patterns in an alien species at its invasion front - consequences for invasion speed.

    PubMed

    Herfindal, Ivar; Melis, Claudia; Åhlén, Per-Arne; Dahl, Fredrik

    2016-08-01

    Efficient targeting of actions to reduce the spread of invasive alien species relies on understanding the spatial, temporal, and individual variation of movement, in particular related to dispersal. Such patterns may differ between individuals at the invasion front compared to individuals in established and dense populations due to differences in environmental and ecological conditions such as abundance of conspecifics or sex-specific dispersal affecting the encounter rate of potential mates. We assessed seasonal and diurnal variation in movement pattern (step length and turning angle) of adult male and female raccoon dog at their invasion front in northern Sweden using data from Global Positioning System (GPS)-marked adult individuals and assessed whether male and female raccoon dog differed in their movement behavior. There were few consistent sex differences in movement. The rate of dispersal was rather similar over the months, suggesting that both male and female raccoon dog disperse during most of the year, but with higher speed during spring and summer. There were diurnal movement patterns in both sexes with more directional and faster movement during the dark hours. However, the short summer nights may limit such movement patterns, and long-distance displacement was best explained by fine-scale movement patterns from 18:00 to 05:00, rather than by movement patterns only from twilight and night. Simulation of dispersing raccoon dogs suggested a higher frequency of male-female encounters that were further away from the source population for the empirical data compared to a scenario with sex differences in movement pattern. The lack of sex differences in movement pattern at the invasion front results in an increased likelihood for reproductive events far from the source population. Animals outside the source population should be considered potential reproducing individuals, and a high effort to capture such individuals is needed throughout the year to prevent

  5. A spatiotemporal mining framework for abnormal association patterns in marine environments with a time series of remote sensing images

    NASA Astrophysics Data System (ADS)

    Xue, Cunjin; Song, Wanjiao; Qin, Lijuan; Dong, Qing; Wen, Xiaoyang

    2015-06-01

    A spatiotemporal mining framework is a novel tool for the analysis of marine association patterns using multiple remote sensing images. From data pretreatment, to algorithm design, to association rule mining and pattern visualization, this paper outlines a spatiotemporal mining framework for abnormal association patterns in marine environments, including pixel-based and object-based mining models. Within this framework, some key issues are also addressed. In the data pretreatment phase, we propose an algorithm for extracting abnormal objects or pixels over marine surfaces, and construct a mining transaction table with object-based and pixel-based strategies. In the mining algorithm phase, a recursion method to construct a direct association pattern tree is addressed with an asymmetric mutual information table, and a recursive mining algorithm to find frequent items. In the knowledge visualization phase, a "Dimension-Attributes" visualization framework is used to display spatiotemporal association patterns. Finally, spatiotemporal association patterns for marine environmental parameters in the Pacific Ocean are identified, and the results prove the effectiveness and the efficiency of the proposed mining framework.

  6. New insights into turbulent pedestrian movement pattern in crowd-quakes

    NASA Astrophysics Data System (ADS)

    Ma, J.; Song, W. G.; Lo, S. M.; Fang, Z. M.

    2013-02-01

    Video recordings right before the Love Parade disaster have been quantitatively analyzed to explore the bursts of unusual crowd movement patterns, crowd-quakes. The pedestrian movement pattern in this incident was special for the reason that it happened in a congested counter flow scenario, where stopped pedestrians were involved. No one was believed to have pushed others intentionally at the beginning, however, under this situation, the body contacts among the pedestrians still induced a force spread, which then led to velocity fluctuation. As indicated by the individual velocity-related features, the densely crowded pedestrian movement displayed turbulent flow features. Further analyzing the overall flow field, we also found that the pedestrian flow field shared typical patterns with turbulent fluid flow. As a result of the turbulent state, different clusters of pedestrians displayed different velocity features. Thus crowd pressure which took into account the velocity and density information was proved to be a good indicator of crowd disasters. Based on these essential features of pedestrian crowd-quakes, a minimal model, i.e., a pedestrian crowd-quake model, was established. Effects including pedestrian gait, stress conservation level and personal intention to escape were explored.

  7. Identification of cross-country skiing movement patterns using micro-sensors.

    PubMed

    Marsland, Finn; Lyons, Keith; Anson, Judith; Waddington, Gordon; Macintosh, Colin; Chapman, Dale

    2012-01-01

    This study investigated the potential of micro-sensors for use in the identification of the main movement patterns used in cross-country skiing. Data were collected from four elite international and four Australian athletes in Europe and in Australia using a MinimaxX™ unit containing accelerometer, gyroscope and GPS sensors. Athletes performed four skating techniques and three classical techniques on snow at moderate velocity. Data from a single micro-sensor unit positioned in the centre of the upper back was sufficient to visually identify cyclical movement patterns for each technique. The general patterns for each technique were identified clearly across all athletes while at the same time distinctive characteristics for individual athletes were observed. Differences in speed, snow condition and gradient of terrain were not controlled in this study and these factors could have an effect on the data patterns. Development of algorithms to process the micro-sensor data into kinematic measurements would provide coaches and scientists with a valuable performance analysis tool. Further research is needed to develop such algorithms and to determine whether the patterns are consistent across a range of different speeds, snow conditions and terrain, and for skiers of differing ability.

  8. Identification of Cross-Country Skiing Movement Patterns Using Micro-Sensors

    PubMed Central

    Marsland, Finn; Lyons, Keith; Anson, Judith; Waddington, Gordon; Macintosh, Colin; Chapman, Dale

    2012-01-01

    This study investigated the potential of micro-sensors for use in the identification of the main movement patterns used in cross-country skiing. Data were collected from four elite international and four Australian athletes in Europe and in Australia using a MinimaxX™ unit containing accelerometer, gyroscope and GPS sensors. Athletes performed four skating techniques and three classical techniques on snow at moderate velocity. Data from a single micro-sensor unit positioned in the centre of the upper back was sufficient to visually identify cyclical movement patterns for each technique. The general patterns for each technique were identified clearly across all athletes while at the same time distinctive characteristics for individual athletes were observed. Differences in speed, snow condition and gradient of terrain were not controlled in this study and these factors could have an effect on the data patterns. Development of algorithms to process the micro-sensor data into kinematic measurements would provide coaches and scientists with a valuable performance analysis tool. Further research is needed to develop such algorithms and to determine whether the patterns are consistent across a range of different speeds, snow conditions and terrain, and for skiers of differing ability. PMID:22666075

  9. Movement patterns and study area boundaries: Influences on survival estimation in capture-mark-recapture studies

    USGS Publications Warehouse

    Horton, G.E.; Letcher, B.H.

    2008-01-01

    The inability to account for the availability of individuals in the study area during capture-mark-recapture (CMR) studies and the resultant confounding of parameter estimates can make correct interpretation of CMR model parameter estimates difficult. Although important advances based on the Cormack-Jolly-Seber (CJS) model have resulted in estimators of true survival that work by unconfounding either death or recapture probability from availability for capture in the study area, these methods rely on the researcher's ability to select a method that is correctly matched to emigration patterns in the population. If incorrect assumptions regarding site fidelity (non-movement) are made, it may be difficult or impossible as well as costly to change the study design once the incorrect assumption is discovered. Subtleties in characteristics of movement (e.g. life history-dependent emigration, nomads vs territory holders) can lead to mixtures in the probability of being available for capture among members of the same population. The result of these mixtures may be only a partial unconfounding of emigration from other CMR model parameters. Biologically-based differences in individual movement can combine with constraints on study design to further complicate the problem. Because of the intricacies of movement and its interaction with other parameters in CMR models, quantification of and solutions to these problems are needed. Based on our work with stream-dwelling populations of Atlantic salmon Salmo salar, we used a simulation approach to evaluate existing CMR models under various mixtures of movement probabilities. The Barker joint data model provided unbiased estimates of true survival under all conditions tested. The CJS and robust design models provided similarly unbiased estimates of true survival but only when emigration information could be incorporated directly into individual encounter histories. For the robust design model, Markovian emigration (future

  10. Frequency and patterns of abnormality detected by iodine-123 amine emission CT after cerebral infarction

    SciTech Connect

    Brott, T.G.; Gelfand, M.J.; Williams, C.C.; Spilker, J.A.; Hertzberg, V.S.

    1986-03-01

    Single photon emission computed tomography (SPECT) was performed in 31 patients with cerebral infarction and 13 who had had transient ischemic attacks, using iodine-123-labeled N,N,N'-trimethyl-N'-(2-hydroxyl-3-methyl-5-iodobenzyl)-1,3-propanediamin e (I-123-HIPDM) as the radiopharmaceutical. SPECT scans were compared with computed tomographic (CT) scans. SPECT was as sensitive as CT in detecting cerebral infarction (94% vs. 84%). The abnormalities were larger on the SPECT scans than on the CT scans in 19 cases, equal in seven, and smaller in five (SPECT abnormalities greater than or equal to CT abnormalities in 86% of cases). Fifteen of 30 patients with hemispheric infarction had decreased perfusion (decreased uptake of I-123-HIPDM) to the cerebellar hemisphere contralateral to the cerebral hemisphere involved by the infarction (crossed cerebellar diaschisis). Nine of these 15 patients had major motor deficits, while only one of the 15 without crossed cerebellar diaschisis had a major motor deficit.

  11. Adaptable Neighbours: Movement Patterns of GPS-Collared Leopards in Human Dominated Landscapes in India

    PubMed Central

    Odden, Morten; Athreya, Vidya; Rattan, Sandeep; Linnell, John D. C.

    2014-01-01

    Understanding the nature of the interactions between humans and wildlife is of vital importance for conflict mitigation. We equipped five leopards with GPS-collars in Maharashtra (4) and Himachal Pradesh (1), India, to study movement patterns in human-dominated landscapes outside protected areas. An adult male and an adult female were both translocated 52 km, and exhibited extensive, and directional, post release movements (straight line movements: male  = 89 km in 37 days, female  = 45 km in 5 months), until they settled in home ranges of 42 km2 (male) and 65 km2 (female). The three other leopards, two adult females and a young male were released close to their capture sites and used small home ranges of 8 km2 (male), 11 km2 and 15 km2 (females). Movement patterns were markedly nocturnal, with hourly step lengths averaging 339±9.5 m (SE) during night and 60±4.1 m during day, and night locations were significantly closer to human settlements than day locations. However, more nocturnal movements were observed among those three living in the areas with high human population densities. These visited houses regularly at nighttime (20% of locations <25 m from houses), but rarely during day (<1%). One leopard living in a sparsely populated area avoided human settlements both day and night. The small home ranges of the leopards indicate that anthropogenic food resources may be plentiful although wild prey is absent. The study provides clear insights into the ability of leopards to live and move in landscapes that are extremely modified by human activity. PMID:25390067

  12. Quantifying positional and temporal movement patterns in professional rugby union using global positioning system.

    PubMed

    Jones, Marc R; West, Daniel J; Crewther, Blair T; Cook, Christian J; Kilduff, Liam P

    2015-01-01

    This study assessed the positional and temporal movement patterns of professional rugby union players during competition using global positioning system (GPS) units. GPS data were collected from 33 professional rugby players from 13 matches throughout the 2012-2013 season sampling at 10 Hz. Players wore GPS units from which information on distances, velocities, accelerations, exertion index, player load, contacts, sprinting and repeated high-intensity efforts (RHIE) were derived. Data files from players who played over 60 min (n = 112) were separated into five positional groups (tight and loose forwards; half, inside and outside backs) for match analysis. A further comparison of temporal changes in movement patterns was also performed using data files from those who played full games (n = 71). Significant positional differences were found for movement characteristics during performance (P < 0.05). Results demonstrate that inside and outside backs have greatest high-speed running demands; however, RHIE and contact demands are greatest in loose forwards during match play. Temporal analysis of all players displayed significant differences in player load, cruising and striding between halves, with measures of low- and high-intensity movement and acceleration/deceleration significantly declining throughout each half. Our data demonstrate significant positional differences for a number of key movement variables which provide a greater understanding of positional requirements of performance. This in turn may be used to develop progressive position-specific drills that elicit specific adaptations and provide objective measures of preparedness. Knowledge of performance changes may be used when developing drills and should be considered when monitoring and evaluating performance.

  13. Adaptable neighbours: movement patterns of GPS-collared leopards in human dominated landscapes in India.

    PubMed

    Odden, Morten; Athreya, Vidya; Rattan, Sandeep; Linnell, John D C

    2014-01-01

    Understanding the nature of the interactions between humans and wildlife is of vital importance for conflict mitigation. We equipped five leopards with GPS-collars in Maharashtra (4) and Himachal Pradesh (1), India, to study movement patterns in human-dominated landscapes outside protected areas. An adult male and an adult female were both translocated 52 km, and exhibited extensive, and directional, post release movements (straight line movements: male = 89 km in 37 days, female = 45 km in 5 months), until they settled in home ranges of 42 km2 (male) and 65 km2 (female). The three other leopards, two adult females and a young male were released close to their capture sites and used small home ranges of 8 km2 (male), 11 km2 and 15 km2 (females). Movement patterns were markedly nocturnal, with hourly step lengths averaging 339±9.5 m (SE) during night and 60±4.1 m during day, and night locations were significantly closer to human settlements than day locations. However, more nocturnal movements were observed among those three living in the areas with high human population densities. These visited houses regularly at nighttime (20% of locations <25 m from houses), but rarely during day (<1%). One leopard living in a sparsely populated area avoided human settlements both day and night. The small home ranges of the leopards indicate that anthropogenic food resources may be plentiful although wild prey is absent. The study provides clear insights into the ability of leopards to live and move in landscapes that are extremely modified by human activity.

  14. Spreading Photoparoxysmal EEG Response is Associated with an Abnormal Cortical Excitability Pattern

    ERIC Educational Resources Information Center

    Siniatchkin, Michael; Groppa, Sergey; Jerosch, Bettina; Muhle, Hiltrud; Kurth, Christoph; Shepherd, Alex J.; Siebner, Hartwig; Stephani, Ulrich

    2007-01-01

    Photosensitivity or photoparoxysmal response (PPR) is a highly heritable electroencephalographic trait characterized by an abnormal cortical response to intermittent photic stimulation (IPS). In PPR-positive individuals, IPS induces spikes, spike-waves or intermittent slow waves. The PPR may be restricted to posterior visual areas (i.e. local PPR…

  15. Effects of individual differences in verbal skills on eye-movement patterns during sentence reading

    PubMed Central

    Kuperman, Victor; Van Dyke, Julie A.

    2011-01-01

    This study is a large-scale exploration of the influence that individual reading skills exert on eye-movement behavior in sentence reading. Seventy one non-college-bound 16–24 year-old speakers of English completed a battery of 18 verbal and cognitive skill assessments, and read a series of sentences as their eye movements were monitored. Statistical analyses were performed to establish what tests of reading abilities were predictive of eye-movement patterns across this population and how strong the effects were. We found that individual scores in rapid automatized naming and word identification tests (i) were the only participant variables with reliable predictivity throughout the time-course of reading; (ii) elicited effects that superceded in magnitude the effects of established predictors like word length or frequency; and (iii) strongly modulated the influence of word length and frequency on fixation times. We discuss implications of our findings for testing reading ability, as well as for research of eye-movements in reading. PMID:21709808

  16. Variation in movement patterns of red drum (Sciaenops ocellatus) inferred from conventional tagging and ultrasonic telemetry

    USGS Publications Warehouse

    Bacheler, N.M.; Paramore, L.M.; Burdick, S.M.; Buckel, J.A.; Hightower, J.E.

    2009-01-01

    We used 25 years of conventional tagging data (n=6173 recoveries) and 3 years of ultrasonic telemetry data (n=105 transmitters deployed) to examine movement rates and directional preferences of four age classes of red drum (Sciaenops ocellatus) in estuarine and coastal waters of North Carolina. Movement rates of conventionally tagged red drum were dependent on the age, region, and season of tagging. Age-1 and age-2 red drum tagged along the coast generally moved along the coast, whereas fish tagged in oligohaline waters far from the coast were primarily recovered in coastal regions in fall months. Adult (age-4+) red drum moved from overwintering grounds on the continental shelf through inlets into Pamlico Sound in spring and summer months and departed in fall. Few tagged red drum were recovered in adjacent states (0.6% of all recoveries); however, some adult red drum migrated seasonally from overwintering grounds in coastal North Carolina northward to Virginia in spring, returning in fall. Age-2 transmittertracked red drum displayed seasonal emigration from a small tributary, but upstream and downstream movements within the tributary were correlated with fluctuating salinity regimes and not season. Large-scale conventional tagging and ultrasonic telemetry programs can provide valuable insights into the complex movement patterns of estuarine fish.

  17. Effects of individual differences in verbal skills on eye-movement patterns during sentence reading.

    PubMed

    Kuperman, Victor; Van Dyke, Julie A

    2011-07-01

    This study is a large-scale exploration of the influence that individual reading skills exert on eye-movement behavior in sentence reading. Seventy one non-college-bound 16-24 year-old speakers of English completed a battery of 18 verbal and cognitive skill assessments, and read a series of sentences as their eye movements were monitored. Statistical analyses were performed to establish what tests of reading abilities were predictive of eye-movement patterns across this population and how strong the effects were. We found that individual scores in rapid automatized naming and word identification tests (i) were the only participant variables with reliable predictivity throughout the time-course of reading; (ii) elicited effects that superceded in magnitude the effects of established predictors like word length or frequency; and (iii) strongly modulated the influence of word length and frequency on fixation times. We discuss implications of our findings for testing reading ability, as well as for research of eye-movements in reading.

  18. [Central Pattern Generators: Mechanisms of the Activity and Their Role in the Control of "Automatic" Movements].

    PubMed

    Arshavsky, I; Deliagina, T G; Orlovsky, G N

    2015-01-01

    Central pattern generators (CPGs) are a set of interconnected neurons capable of generating a basic pattern of motor output underlying "automatic" movements (breathing, locomotion, chewing, swallowing, and so on) in the absence of afferent signals from the executive motor apparatus. They can be divided into the constitutive CPGs active throughout the entire lifetime (respiratory CPGs) and conditional CPGs controlling episodic movements (locomotion, chewing, swallowing, and others). Since a motor output of CPGs is determined by their internal organization, the activities of the conditional CPGs are initiated by simple commands coming from higher centers. We describe the structural and functional organization of the locomotor CPGs in the marine mollusk Clione limacina, lamprey, frog embryo, and laboratory mammals (cat, mouse, and rat), CPGs controlling the respiratory and swallowing movements in mammals, and CPGs controlling discharges of the electric organ in the gymnotiform fish. It is shown that in all these cases, the generation of rhythmic motor output is based both on the endogenous (pacemaker) activity of specific groups of interneurons and on interneural interactions. These two interrelated mechanisms complement each other, ensuring the high reliability of CPG functionality. We discuss how the experience obtained in studying CPGs can be used to understand mechanisms of more complex functions of the brain, including its cognitive functions.

  19. The effects of binge-pattern alcohol consumption on orthodontic tooth movement

    PubMed Central

    de Araujo, Cristiano Miranda; Johann, Aline Cristina Batista Rodrigues; Camargo, Elisa Souza; Tanaka, Orlando Motohiro

    2014-01-01

    OBJECTIVE: This study aimed to assess tissue changes during orthodontic movement after binge-pattern ethanol 20% exposure. METHODS: Male Wistar rats (n = 54) were divided into two groups. The control group (CG) received 0.9% saline solution, while the experimental group (EG) received 20% ethanol in 0.9% saline solution (3 g/kg/day). On the 30th day, a force of 25 cN was applied with a nickel-titanium closed coil spring to move the maxillary right first molar mesially. The groups were further divided into three subgroups (2, 14 and 28 days). Tartrate-resistant acid phosphatase and picrosirius were used to assess bone resorption and neoformation, respectively. Data were compared by two-way ANOVA, Tukey's HSD, Games-Howell and chi-square test. Significance level was set at 5%. RESULTS: There was a decrease in the number of osteoclasts in EG at day 28. The percentage of collagen showed no interaction between group and time. CONCLUSION: Binge-pattern 20% ethanol promoted less bone resorption at the end of tooth movement, thereby suggesting delay in tooth movement. PMID:25628085

  20. Identification of abnormal motor cortex activation patterns in children with cerebral palsy by functional near-infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Khan, Bilal; Tian, Fenghua; Behbehani, Khosrow; Romero, Mario I.; Delgado, Mauricio R.; Clegg, Nancy J.; Smith, Linsley; Reid, Dahlia; Liu, Hanli; Alexandrakis, George

    2010-05-01

    We demonstrate the utility of functional near-infrared spectroscopy (fNIRS) as a tool for physicians to study cortical plasticity in children with cerebral palsy (CP). Motor cortex activation patterns were studied in five healthy children and five children with CP (8.4+/-2.3 years old in both groups) performing a finger-tapping protocol. Spatial (distance from center and area difference) and temporal (duration and time-to-peak) image metrics are proposed as potential biomarkers for differentiating abnormal cortical activation in children with CP from healthy pediatric controls. In addition, a similarity image-analysis concept is presented that unveils areas that have similar activation patterns as that of the maximum activation area, but are not discernible by visual inspection of standard activation images. Metrics derived from the images presenting areas of similarity are shown to be sensitive identifiers of abnormal activation patterns in children with CP. Importantly, the proposed similarity concept and related metrics may be applicable to other studies for the identification of cortical activation patterns by fNIRS.

  1. Adult-onset multiple acyl CoA dehydrogenation deficiency associated with an abnormal isoenzyme pattern of serum lactate dehydrogenase.

    PubMed

    Sugai, Fuminobu; Baba, Kousuke; Toyooka, Keiko; Liang, Wen-Chen; Nishino, Ichizo; Yamadera, Misaki; Sumi, Hisae; Fujimura, Harutoshi; Nishikawa, Yoshiro

    2012-02-01

    We report a case of a 37 year-old male with multiple acyl-CoA dehydrogenation deficiency (MADD). The patient had suffered from exercise intolerance in his hip and thigh muscles for one year. Then, restriction of carbohydrates for a diet made his symptoms rapidly deteriorate. Blood test revealed compound heterozygosity for two novel missense mutations in the electron transfer flavoprotein dehydrogenase gene (ETFDH), and an abnormal LDH isoenzyme pattern: LDH-1 (60.0%) and LDH-2 (26.0%) predominated with abnormally elevated LDH-1/LDH-2 ratio (2.3), compared with muscle-derived LDH-5 (4.0%). Oral riboflavin treatment significantly improved his exercise intolerance and the LDH profile: LDH-1 (34.4%), LDH-2 (34.9%), LDH-5 (6.9%) and LDH-1/LDH-2 ratio (1.0). The abnormal LDH isoenzyme pattern may be one feature of adult-onset MADD selectively affecting type I muscle fibers with relatively high LDH-1 content. PMID:21907580

  2. [Angiodysplasia of moya-moya type disclosed by choreic unvoluntary abnormal movements during oral contraception. Apropos of 2 cases].

    PubMed

    Pelletier, J; Cabanot, C; Lévrier, O; Thuillier, J N; Chérif, A A

    1997-07-01

    Two seventeen year-old women, developed acute onset left choreic movements following two months and two weeks use of oral contraceptives. Left hemiparesia appeared a few days later, while involuntary movements discontinued. Cranial CT scan and MRI showed bilateral ischemic lesion in the frontal region for the first case and isolated lesion in the right centrum ovale for the second. Angiography showed nearly complete obstruction of the terminal portion of the internal carotid artery with an outline Moya-Moya network. After discontinuing oral contraceptives, there has been no relapse of neurologic dysfunction for more than three years for the first case and twelve months for the second one. The role of perfusion insufficiency in limb-shaking carotid transient ischemic attack is discussed and the possible relations between oral contraceptives, chorea and angiographic features resembling Moya-Moya disease are evaluated. PMID:9684005

  3. A masculinized skeletomusculature is not necessary for male-typical patterns of food-protective movement.

    PubMed

    Field, Evelyn F; Watson, Neil V; Whishaw, Ian Q; Pellis, Sergio M

    2005-01-01

    Although sexual dimorphism in movement has been documented in rodents, the extent to which it relates to dimorphic neural control versus dimorphic body size/structure is unclear. We have shown previously that male and female rats are sexually dimorphic with regards to the lateral movements and hindpaw stepping they use to protect a food item. We addressed the question of whether this sexual dimorphism is due to sex differences in peripheral skeletomusculature or in the CNS by examining the movement composition used during dodging to protect a food item by tfm-affected males and their wild-type male (WTM) and female (WTF) controls. The tfm-affected male, while genetically male, develops internal testes that secrete testosterone, but is phenotypically female due to a failure of androgen receptor-mediated masculinization of the periphery. Masculinization of the CNS of tfm-affected males, however, is primarily accomplished by the actions of testosterone's aromatized metabolite estradiol acting via estrogen receptors. Thus the tfm-affected male provides an assay by which the relative contributions of the skeletomusculature or CNS to sex differences in movement organization can be addressed. We found that female wild-type animals were significantly different from both the tfm-affected and wild-type males. There were no significant differences in dodge patterns used by tfm-affected males and their wild-type male controls. This study provides evidence that the sex differences in dodging patterns are mediated primarily by CNS mechanisms and are not primarily dependent on a male- or female-typical skeletomusculature. PMID:15579265

  4. Larval dispersal and movement patterns of coral reef fishes, and implications for marine reserve network design.

    PubMed

    Green, Alison L; Maypa, Aileen P; Almany, Glenn R; Rhodes, Kevin L; Weeks, Rebecca; Abesamis, Rene A; Gleason, Mary G; Mumby, Peter J; White, Alan T

    2015-11-01

    Well-designed and effectively managed networks of marine reserves can be effective tools for both fisheries management and biodiversity conservation. Connectivity, the demographic linking of local populations through the dispersal of individuals as larvae, juveniles or adults, is a key ecological factor to consider in marine reserve design, since it has important implications for the persistence of metapopulations and their recovery from disturbance. For marine reserves to protect biodiversity and enhance populations of species in fished areas, they must be able to sustain focal species (particularly fishery species) within their boundaries, and be spaced such that they can function as mutually replenishing networks whilst providing recruitment subsidies to fished areas. Thus the configuration (size, spacing and location) of individual reserves within a network should be informed by larval dispersal and movement patterns of the species for which protection is required. In the past, empirical data regarding larval dispersal and movement patterns of adults and juveniles of many tropical marine species have been unavailable or inaccessible to practitioners responsible for marine reserve design. Recent empirical studies using new technologies have also provided fresh insights into movement patterns of many species and redefined our understanding of connectivity among populations through larval dispersal. Our review of movement patterns of 34 families (210 species) of coral reef fishes demonstrates that movement patterns (home ranges, ontogenetic shifts and spawning migrations) vary among and within species, and are influenced by a range of factors (e.g. size, sex, behaviour, density, habitat characteristics, season, tide and time of day). Some species move <0.1-0.5 km (e.g. damselfishes, butterflyfishes and angelfishes), <0.5-3 km (e.g. most parrotfishes, goatfishes and surgeonfishes) or 3-10 km (e.g. large parrotfishes and wrasses), while others move tens to hundreds

  5. Larval dispersal and movement patterns of coral reef fishes, and implications for marine reserve network design.

    PubMed

    Green, Alison L; Maypa, Aileen P; Almany, Glenn R; Rhodes, Kevin L; Weeks, Rebecca; Abesamis, Rene A; Gleason, Mary G; Mumby, Peter J; White, Alan T

    2015-11-01

    Well-designed and effectively managed networks of marine reserves can be effective tools for both fisheries management and biodiversity conservation. Connectivity, the demographic linking of local populations through the dispersal of individuals as larvae, juveniles or adults, is a key ecological factor to consider in marine reserve design, since it has important implications for the persistence of metapopulations and their recovery from disturbance. For marine reserves to protect biodiversity and enhance populations of species in fished areas, they must be able to sustain focal species (particularly fishery species) within their boundaries, and be spaced such that they can function as mutually replenishing networks whilst providing recruitment subsidies to fished areas. Thus the configuration (size, spacing and location) of individual reserves within a network should be informed by larval dispersal and movement patterns of the species for which protection is required. In the past, empirical data regarding larval dispersal and movement patterns of adults and juveniles of many tropical marine species have been unavailable or inaccessible to practitioners responsible for marine reserve design. Recent empirical studies using new technologies have also provided fresh insights into movement patterns of many species and redefined our understanding of connectivity among populations through larval dispersal. Our review of movement patterns of 34 families (210 species) of coral reef fishes demonstrates that movement patterns (home ranges, ontogenetic shifts and spawning migrations) vary among and within species, and are influenced by a range of factors (e.g. size, sex, behaviour, density, habitat characteristics, season, tide and time of day). Some species move <0.1-0.5 km (e.g. damselfishes, butterflyfishes and angelfishes), <0.5-3 km (e.g. most parrotfishes, goatfishes and surgeonfishes) or 3-10 km (e.g. large parrotfishes and wrasses), while others move tens to hundreds

  6. Perception and discrimination of movement and biological motion patterns in fish.

    PubMed

    Schluessel, V; Kortekamp, N; Cortes, J A Ortiz; Klein, A; Bleckmann, H

    2015-09-01

    Vision is of primary importance for many fish species, as is the recognition of movement. With the exception of one study, assessing the influence of conspecific movement on shoaling behaviour, the perception of biological motion in fish had not been studied in a cognitive context. The aim of the present study was therefore to assess the discrimination abilities of two teleost species in regard to simple and complex movement patterns of dots and objects, including biological motion patterns using point and point-light displays (PDs and PLDs). In two-alternative forced-choice experiments, in which choosing the designated positive stimulus was food-reinforced, fish were first tested in their ability to distinguish the video of a stationary black dot on a light background from the video of a moving black dot presented at different frequencies and amplitudes. While all fish succeeded in learning the task, performance declined with decreases in either or both parameters. In subsequent tests, cichlids and damselfish distinguished successfully between the videos of two dots moving at different speeds and amplitudes, between two moving dot patterns (sinus vs. expiring sinus) and between animated videos of two moving organisms (trout vs. eel). Transfer tests following the training of the latter showed that fish were unable to identify the positive stimulus (trout) by means of its PD alone, thereby indicating that the ability of humans to spontaneously recognize an organism based on its biological motion may not be present in fish. All participating individuals successfully discriminated between two PDs and two PLDs after a short period of training, indicating that biological motions presented in form of PLDs are perceived and can be distinguished. Results were the same for the presentation of dark dots on a light background and light dots on a dark background.

  7. Foraging ecology and movement patterns of jumbo squid (Dosidicus gigas) in the California Current System

    NASA Astrophysics Data System (ADS)

    Field, John C.; Elliger, Carl; Baltz, Ken; Gillespie, Graham E.; Gilly, William F.; Ruiz-Cooley, R. I.; Pearse, Devon; Stewart, Julia S.; Matsubu, William; Walker, William A.

    2013-10-01

    From 2002 to 2010, the jumbo squid (Dosidicus gigas) has been regularly encountered in large numbers throughout the California Current System (CCS). This species, usually found in subtropical waters, could affect coastal pelagic ecosystems and fisheries as both predator and prey. Neither the abundance of jumbo squid nor the optimal ocean conditions in which they flourish are well known. To understand better the potential impacts of this species on both commercial fisheries and on food-web structure we collected nearly 900 specimens from waters of the CCS, covering over 20° of latitude, over a range of depths and seasons. We used demographic information (size, sex, and maturity state) and analyzed stomach contents using morphological and molecular methods to best understand the foraging ecology of this species in different habitats of the CCS. Squid were found to consume a broad array of prey. Prey in offshore waters generally reflected the forage base reported in previous studies (mainly mesopelagic fishes and squids), whereas in more coastal waters (shelf, shelf break and slope habitats) squid foraged on a much broader mix that included substantial numbers of coastal pelagic fishes (Pacific herring and northern anchovy, as well as osmerids and salmonids in northern waters) and groundfish (Pacific hake, several species of rockfish and flatfish). We propose a seasonal movement pattern, based on size and maturity distributions along with qualitative patterns of presence or absence, and discuss the relevance of both the movement and distribution of jumbo squid over space and time. We find that jumbo squid are a generalist predator, which feeds primarily on small, pelagic or mesopelagic micronekton but also on larger fishes when they are available. We also conclude that interactions with and potential impacts on ecosystems likely vary over space and time, in response to both seasonal movement patterns and highly variable year-to-year abundance of the squid themselves.

  8. Using dynamic Brownian bridge movement modelling to measure temporal patterns of habitat selection.

    PubMed

    Byrne, Michael E; Clint McCoy, J; Hinton, Joseph W; Chamberlain, Michael J; Collier, Bret A

    2014-09-01

    Accurately describing animal space use is vital to understanding how wildlife use habitat. Improvements in GPS technology continue to facilitate collection of telemetry data at high spatial and temporal resolutions. Application of the recently introduced dynamic Brownian bridge movement model (dBBMM) to such data is promising as the method explicitly incorporates the behavioural heterogeneity of a movement path into the estimated utilization distribution (UD). Utilization distributions defining space use are normally estimated for time-scales ranging from weeks to months, obscuring much of the fine-scale information available from high-volume GPS data sets. By accounting for movement heterogeneity, the dBBMM provides a rigorous, behaviourally based estimate of space use between each set of relocations. Focusing on UDs generated between individual sets of locations allows us to quantify fine-scale circadian variation in habitat use. We used the dBBMM to estimate UDs bounding individual time steps for three terrestrial species with different life histories to illustrate how the method can be used to identify fine-scale variations in habitat use. We also demonstrate how dBBMMs can be used to characterize circadian patterns of habitat selection and link fine-scale patterns of habitat use to behaviour. We observed circadian patterns of habitat use that varied seasonally for a white-tailed deer (Odocoileus virginianus) and coyote (Canis latrans). We found seasonal patterns in selection by the white-tailed deer and were able to link use of conifer forests and agricultural fields to behavioural state of the coyote. Additionally, we were able to quantify the date in which a Rio Grande wild turkey (Meleagris gallopavo intermedia) initiated laying as well as when during the day, she was most likely to visit the nest site to deposit eggs. The ability to quantify circadian patterns of habitat use may have important implications for research and management of wildlife

  9. Identification of Abnormal System Noise Temperature Patterns in Deep Space Network Antennas Using Neural Network Trained Fuzzy Logic

    NASA Technical Reports Server (NTRS)

    Lu, Thomas; Pham, Timothy; Liao, Jason

    2011-01-01

    This paper presents the development of a fuzzy logic function trained by an artificial neural network to classify the system noise temperature (SNT) of antennas in the NASA Deep Space Network (DSN). The SNT data were classified into normal, marginal, and abnormal classes. The irregular SNT pattern was further correlated with link margin and weather data. A reasonably good correlation is detected among high SNT, low link margin and the effect of bad weather; however we also saw some unexpected non-correlations which merit further study in the future.

  10. How landscape dynamics link individual- to population-level movement patterns: A multispecies comparison of ungulate relocation data

    USGS Publications Warehouse

    Mueller, T.; Olson, K.A.; Dressler, G.; Leimgruber, P.; Fuller, T.K.; Nicolson, C.; Novaro, A.J.; Bolgeri, M.J.; Wattles, D.; DeStefano, S.; Calabrese, J.M.; Fagan, W.F.

    2011-01-01

    Aim To demonstrate how the interrelations of individual movements form large-scale population-level movement patterns and how these patterns are associated with the underlying landscape dynamics by comparing ungulate movements across species. Locations Arctic tundra in Alaska and Canada, temperate forests in Massachusetts, Patagonian Steppes in Argentina, Eastern Steppes in Mongolia. Methods We used relocation data from four ungulate species (barren-ground caribou, Mongolian gazelle, guanaco and moose) to examine individual movements and the interrelation of movements among individuals. We applied and developed a suite of spatial metrics that measure variation in movement among individuals as population dispersion, movement coordination and realized mobility. Taken together, these metrics allowed us to quantify and distinguish among different large-scale population-level movement patterns such as migration, range residency and nomadism. We then related the population-level movement patterns to the underlying landscape vegetation dynamics via long-term remote sensing measurements of the temporal variability, spatial variability and unpredictability of vegetation productivity. Results Moose, which remained in sedentary home ranges, and guanacos, which were partially migratory, exhibited relatively short annual movements associated with landscapes having very little broad-scale variability in vegetation. Caribou and gazelle performed extreme long-distance movements that were associated with broad-scale variability in vegetation productivity during the peak of the growing season. Caribou exhibited regular seasonal migration in which individuals were clustered for most of the year and exhibited coordinated movements. In contrast, gazelle were nomadic, as individuals were independently distributed and moved in an uncoordinated manner that relates to the comparatively unpredictable (yet broad-scale) vegetation dynamics of their landscape. Main conclusions We show how

  11. Running the gauntlet: regional movement patterns of Manta alfredi through a complex of parks and fisheries.

    PubMed

    Germanov, Elitza S; Marshall, Andrea D

    2014-01-01

    Manta rays (Genus Manta) are economically important for fisheries and tourism in Indonesia. These species have been listed by the International Union for the Conservation of Nature Red List as Vulnerable to extinction; therefore, human exploitation of manta rays must be regulated. A better understanding of the habitat use and movement patterns of manta rays in Indonesia is needed in order to employ effective conservation measures. To gain better insight into the movements of Manta alfredi we used 'Manta Matcher', an online database with an integrated automated matching algorithm, to compare photographs from 2,604 encounters of M. alfredi collected by recreational divers and dive operators throughout Indonesia over a nine-year period. This photographic comparison revealed that manta rays migrated between regional sanctuaries such as Nusa Penida, the Gili Islands, and the Komodo National Park (up to 450 km straight-line distance). The areas between these sanctuaries are heavily fished and trafficked by ships, and when manta rays travel through these regions they risk being fished and injured by ship strikes. These long-range manta ray movements suggest connectivity between M. alfredi populations in neighboring islands and raise concerns about the future management of regional populations. It is recommended that a national conservation strategy be developed to protect the remaining populations in the country.

  12. Movement patterns of juvenile whale sharks tagged at an aggregation site in the Red Sea.

    PubMed

    Berumen, Michael L; Braun, Camrin D; Cochran, Jesse E M; Skomal, Gregory B; Thorrold, Simon R

    2014-01-01

    Conservation efforts aimed at the whale shark, Rhincodon typus, remain limited by a lack of basic information on most aspects of its ecology, including global population structure, population sizes and movement patterns. Here we report on the movements of 47 Red Sea whale sharks fitted with three types of satellite transmitting tags from 2009-2011. Most of these sharks were tagged at a single aggregation site near Al-Lith, on the central coast of the Saudi Arabian Red Sea. Individuals encountered at this site were all juveniles based on size estimates ranging from 2.5-7 m total length with a sex ratio of approximately 1∶1. All other known aggregation sites for juvenile whale sharks are dominated by males. Results from tagging efforts showed that most individuals remained in the southern Red Sea and that some sharks returned to the same location in subsequent years. Diving data were recorded by 37 tags, revealing frequent deep dives to at least 500 m and as deep as 1360 m. The unique temperature-depth profiles of the Red Sea confirmed that several whale sharks moved out of the Red Sea while tagged. The wide-ranging horizontal movements of these individuals highlight the need for multinational, cooperative efforts to conserve R. typus populations in the Red Sea and Indian Ocean.

  13. Running the Gauntlet: Regional Movement Patterns of Manta alfredi through a Complex of Parks and Fisheries

    PubMed Central

    Germanov, Elitza S.; Marshall, Andrea D.

    2014-01-01

    Manta rays (Genus Manta) are economically important for fisheries and tourism in Indonesia. These species have been listed by the International Union for the Conservation of Nature Red List as Vulnerable to extinction; therefore, human exploitation of manta rays must be regulated. A better understanding of the habitat use and movement patterns of manta rays in Indonesia is needed in order to employ effective conservation measures. To gain better insight into the movements of Manta alfredi we used ‘Manta Matcher’, an online database with an integrated automated matching algorithm, to compare photographs from 2,604 encounters of M. alfredi collected by recreational divers and dive operators throughout Indonesia over a nine-year period. This photographic comparison revealed that manta rays migrated between regional sanctuaries such as Nusa Penida, the Gili Islands, and the Komodo National Park (up to 450 km straight-line distance). The areas between these sanctuaries are heavily fished and trafficked by ships, and when manta rays travel through these regions they risk being fished and injured by ship strikes. These long-range manta ray movements suggest connectivity between M. alfredi populations in neighboring islands and raise concerns about the future management of regional populations. It is recommended that a national conservation strategy be developed to protect the remaining populations in the country. PMID:25337865

  14. Running the gauntlet: regional movement patterns of Manta alfredi through a complex of parks and fisheries.

    PubMed

    Germanov, Elitza S; Marshall, Andrea D

    2014-01-01

    Manta rays (Genus Manta) are economically important for fisheries and tourism in Indonesia. These species have been listed by the International Union for the Conservation of Nature Red List as Vulnerable to extinction; therefore, human exploitation of manta rays must be regulated. A better understanding of the habitat use and movement patterns of manta rays in Indonesia is needed in order to employ effective conservation measures. To gain better insight into the movements of Manta alfredi we used 'Manta Matcher', an online database with an integrated automated matching algorithm, to compare photographs from 2,604 encounters of M. alfredi collected by recreational divers and dive operators throughout Indonesia over a nine-year period. This photographic comparison revealed that manta rays migrated between regional sanctuaries such as Nusa Penida, the Gili Islands, and the Komodo National Park (up to 450 km straight-line distance). The areas between these sanctuaries are heavily fished and trafficked by ships, and when manta rays travel through these regions they risk being fished and injured by ship strikes. These long-range manta ray movements suggest connectivity between M. alfredi populations in neighboring islands and raise concerns about the future management of regional populations. It is recommended that a national conservation strategy be developed to protect the remaining populations in the country. PMID:25337865

  15. How parasitism, stream substrate, and movement patterns mediate response to disturbance in the snail Elimia flava

    NASA Astrophysics Data System (ADS)

    Tomba, A. M.; Feminella, J. W.

    2005-05-01

    Snails in the genus Elimia are abundant in southeastern USA streams, and also serve as intermediate hosts to parasitic trematodes. Previous work indicated that high-flows decrease snail abundance and trematode prevalence, and others have shown substrate type and snail size affect likelihood of snail dislodgement. To investigate how parasitism, size, substrate, and snail behavior influenced dislodgement, we placed Elimia flava in artificial streams containing tile or gravel substrates, and then exposed them to progressively increasing flow velocities ( ~10, 40, 90 cm/s) for 5 minutes each. We recorded snail behavior and time to dislodgement, and then preserved snails to quantify their size and parasite load. Snails on tile dislodged significantly faster than snails on gravel, and snails with high parasite loads also dislodged faster than snails without parasites. Parasitism also appeared to affect movement patterns: snails showing predominantly downstream movement had higher parasite loads than those that did not. Behavior also affected dislodgement probability, as snails moving upstream or to the waterline remained on the substrate longer than snails not showing those behaviors. Parasitism, substrate composition, and snail movement are useful predictors of the likelihood of dislodgement, and parasitism and substrate may both increase snail vulnerability to flow disturbance.

  16. CrossFit athletes exhibit high symmetry of fundamental movement patterns. A cross-sectional study

    PubMed Central

    Tafuri, Silvio; Notarnicola, Angela; Monno, Antonello; Ferretti, Francesco; Moretti, Biagio

    2016-01-01

    Summary Background even if CrossFit training programs accounted actually more than 7500 gyms affiliated in the USA and more than 2000 in Europe and involved today more than 1 million of people, actually there were not several studies about the effect of the CrossFit on the health and sport performance. The aim of these research was to evaluate the performance in 7 fundamental movement patterns using a standardized methods, the Functional Movement Screen (FMS). Methods we enrolled three groups of athletes (age 17–40 years; >6 months of training programs): CrossFitters, body builders and professional weightlifters. FMS test was performed to all people enrolled. Scores of FMS test was examined comparing three groups. Results no differences in the three groups were showed in the mean score values of each test and in total score, except for shoulder mobility test (higher among CrossFitters) and trunk stability push-up test (higher among weightlifter). Agreement between the test performed on the two sides was higher in CrossFit groups for hurdle step (93.2%), in line lung (86%), rotary stability test (95.3%) and shoulder mobility (90.7%; p<0.001). Conclusions CrossFitters seem to have a high level of concordance in the scores achieved in bilateral test. CrossFit seems to produce marked symmetry in some fundamental movements compared to weightlifting and bodybuilding. PMID:27331045

  17. The Number of Trials Required to Obtain a Representative Movement Pattern During a Hurdle Hop Exercise.

    PubMed

    Gore, Shane J; Marshall, Brendan M; Franklyn-Miller, Andrew D; Falvey, Eanna C; Moran, Kieran A

    2016-06-01

    When reporting a subject's mean movement pattern, it is important to ensure that reported values are representative of the subject's typical movement. While previous studies have used the mean of 3 trials, scientific justification of this number is lacking. One approach is to determine statistically how many trials are required to achieve a representative mean. This study compared 4 methods of calculating the number of trials required in a hopping movement to achieve a representative mean. Fifteen males completed 15 trials of a lateral hurdle hop. Range of motion at the trunk, pelvis, hip, knee, and ankle, in addition to peak moments for the latter 3 joints were examined. The number of trials required was computed using a peak intraclass correlation coefficient method, sequential analysis with a bandwidth of acceptable variance in the mean, and a novel method based on the standard error of measurement (SEMind). The number of trials required across all variables ranged from 2 to 12 depending on method, joint, and anatomical plane. The authors advocate the SEMind method as it demonstrated fewer limitations than the other methods. Using the SEMind, the required number of trials for a representative mean during the lateral hurdle hop is 6. PMID:26667614

  18. The Number of Trials Required to Obtain a Representative Movement Pattern During a Hurdle Hop Exercise.

    PubMed

    Gore, Shane J; Marshall, Brendan M; Franklyn-Miller, Andrew D; Falvey, Eanna C; Moran, Kieran A

    2016-06-01

    When reporting a subject's mean movement pattern, it is important to ensure that reported values are representative of the subject's typical movement. While previous studies have used the mean of 3 trials, scientific justification of this number is lacking. One approach is to determine statistically how many trials are required to achieve a representative mean. This study compared 4 methods of calculating the number of trials required in a hopping movement to achieve a representative mean. Fifteen males completed 15 trials of a lateral hurdle hop. Range of motion at the trunk, pelvis, hip, knee, and ankle, in addition to peak moments for the latter 3 joints were examined. The number of trials required was computed using a peak intraclass correlation coefficient method, sequential analysis with a bandwidth of acceptable variance in the mean, and a novel method based on the standard error of measurement (SEMind). The number of trials required across all variables ranged from 2 to 12 depending on method, joint, and anatomical plane. The authors advocate the SEMind method as it demonstrated fewer limitations than the other methods. Using the SEMind, the required number of trials for a representative mean during the lateral hurdle hop is 6.

  19. Movement Patterns of Juvenile Whale Sharks Tagged at an Aggregation Site in the Red Sea

    PubMed Central

    Berumen, Michael L.; Braun, Camrin D.; Cochran, Jesse E. M.; Skomal, Gregory B.; Thorrold, Simon R.

    2014-01-01

    Conservation efforts aimed at the whale shark, Rhincodon typus, remain limited by a lack of basic information on most aspects of its ecology, including global population structure, population sizes and movement patterns. Here we report on the movements of 47 Red Sea whale sharks fitted with three types of satellite transmitting tags from 2009–2011. Most of these sharks were tagged at a single aggregation site near Al-Lith, on the central coast of the Saudi Arabian Red Sea. Individuals encountered at this site were all juveniles based on size estimates ranging from 2.5–7 m total length with a sex ratio of approximately 1∶1. All other known aggregation sites for juvenile whale sharks are dominated by males. Results from tagging efforts showed that most individuals remained in the southern Red Sea and that some sharks returned to the same location in subsequent years. Diving data were recorded by 37 tags, revealing frequent deep dives to at least 500 m and as deep as 1360 m. The unique temperature-depth profiles of the Red Sea confirmed that several whale sharks moved out of the Red Sea while tagged. The wide-ranging horizontal movements of these individuals highlight the need for multinational, cooperative efforts to conserve R. typus populations in the Red Sea and Indian Ocean. PMID:25076407

  20. Movement patterns, habitat use, and survival of Lahontan cutthroat trout in the Truckee River

    USGS Publications Warehouse

    Alexiades, Alexander V.; Peacock, Mary M.; Al-Chokhachy, Robert K.

    2012-01-01

    Habitat fragmentation, hybridization, and competition with nonnative salmonids are viewed as major threats to Lahontan cutthroat trout Oncorhynchus clarkii henshawi. Understanding Lahontan cutthroat trout behavior and survival is a necessary step in the reintroduction and establishment of naturally reproducing populations of Lahontan cutthroat trout. We used weekly radiotelemetry monitoring to examine movement patterns, habitat use, and apparent survival of 42 hatchery-reared Lahontan cutthroat trout in a 16.5-km stretch of the Truckee River, Nevada, across three reaches separated by barriers to upstream movement. We found differences in total movement distances and home range sizes of fish in different reaches within our study area. Fish used pool habitats more than fast water habitats in all reaches. Time of year, stream temperature, and fish standard length covariates had the strongest relationship with apparent survival. Monthly apparent survival was lowest in January, which coincided with the lowest flows and temperatures during the study period. Our results verify the mobility of Lahontan cutthroat trout and indicate that conditions during winter may limit the survival and reintroduction success in the portions of the Truckee River evaluated in this study.

  1. An extrasynaptic GABAergic signal modulates a pattern of forward movement in Caenorhabditis elegans

    PubMed Central

    Shen, Yu; Wen, Quan; Liu, He; Zhong, Connie; Qin, Yuqi; Harris, Gareth; Kawano, Taizo; Wu, Min; Xu, Tianqi; Samuel, Aravinthan DT; Zhang, Yun

    2016-01-01

    As a common neurotransmitter in the nervous system, γ-aminobutyric acid (GABA) modulates locomotory patterns in both vertebrates and invertebrates. However, the signaling mechanisms underlying the behavioral effects of GABAergic modulation are not completely understood. Here, we demonstrate that a GABAergic signal in C. elegans modulates the amplitude of undulatory head bending through extrasynaptic neurotransmission and conserved metabotropic receptors. We show that the GABAergic RME head motor neurons generate undulatory activity patterns that correlate with head bending and the activity of RME causally links with head bending amplitude. The undulatory activity of RME is regulated by a pair of cholinergic head motor neurons SMD, which facilitate head bending, and inhibits SMD to limit head bending. The extrasynaptic neurotransmission between SMD and RME provides a gain control system to set head bending amplitude to a value correlated with optimal efficiency of forward movement. DOI: http://dx.doi.org/10.7554/eLife.14197.001 PMID:27138642

  2. Disturbed Dreaming and the Instability of Sleep: Altered Nonrapid Eye Movement Sleep Microstructure in Individuals with Frequent Nightmares as Revealed by the Cyclic Alternating Pattern

    PubMed Central

    Simor, Péter; Bódizs, Róbert; Horváth, Klára; Ferri, Raffaele

    2013-01-01

    Study Objectives: Nightmares are disturbing mental experiences during sleep that usually result in abrupt awakenings. Frequent nightmares are associated with poor subjective sleep quality, and recent polysomnographic data suggest that nightmare sufferers exhibit impaired sleep continuity during nonrapid eye movement (NREM) sleep. Because disrupted sleep might be related to abnormal arousal processes, the goal of this study was to examine polysomnographic arousal-related activities in a group of nightmare sufferers and a healthy control group. Design: Sleep microstructure analysis was carried out by scoring the cyclic alternating pattern (CAP) in NREM sleep and the arousal index in rapid eye movement (REM) sleep on the second night of the polysomnographic examination. Setting: Hospital-based sleep research laboratory. Participants: There were 17 in the nightmare (NMs) group and 23 in the healthy control (CTLs) group. Interventions: N/A. Measurements and Results: The NMs group exhibited reduced amounts of CAP A1 subtype and increased CAP A2 and A3 subtypes, as well as longer duration of CAP A phases in comparison with CTLs. Moreover, these differences remained significant after controlling for the confounding factors of anxious and depressive symptoms. The absolute number and frequency of REM arousals did not differ significantly between the two groups. Conclusions: The results of our study indicate that NREM sleep microstructure is altered during nonsymptomatic nights of nightmares. Disrupted sleep in the NMs group seems to be related to abnormal arousal processes, specifically an imbalance in sleep-promoting and arousing mechanisms during sleep. Citation: Simor P; Bódizs R; Horváth K; Ferri R. Disturbed dreaming and the instability of sleep: altered nonrapid eye movement sleep microstructure in individuals with frequent nightmares as revealed by the cyclic alternating pattern. SLEEP 2013;36(3):413-419. PMID:23449753

  3. Movement of foraging Tundra Swans explained by spatial pattern in cryptic food densities.

    PubMed

    Klaassen, Raymond H G; Nolet, Bart A; Bankert, Daniëlle

    2006-09-01

    We tested whether Tundra Swans use information on the spatial distribution of cryptic food items (below ground Sago pondweed tubers) to shape their movement paths. In a continuous environment, swans create their own food patches by digging craters, which they exploit in several feeding bouts. Series of short (<1 m) intra-patch movements alternate with longer inter-patch movements (>1 m). Tuber biomass densities showed a positive spatial auto-correlation at a short distance (<3 m), but not at a larger distance (3-8 m). Based on the spatial pattern of the food distribution (which is assumed to be pre-harvest information for the swan) and the energy costs and benefits for different food densities at various distances, we calculated the optimal length of an inter-patch movement. A swan that moves to the patch with the highest gain rate was predicted to move to the adjacent patch (at 1 m) if the food density in the current patch had been high (>25 g/m2) and to a more distant patch (at 7-8 m) if the food density in the current patch had been low (<25 g/m2). This prediction was tested by measuring the response of swans to manipulated tuber densities. In accordance with our predictions, swans moved a long distance (>3 m) from a low-density patch and a short distance (<3 m) from a high-density patch. The quantitative agreement between prediction and observation was greater for swans feeding in pairs than for solitary swans. The result of this movement strategy is that swans visit high-density patches at a higher frequency than on offer and, consequently, achieve a 38% higher long-term gain rate. Swans also take advantage of spatial variance in food abundance by regulating the time in patches, staying longer and consuming more food from rich than from poor patches. We can conclude that the shape of the foraging path is a reflection of the spatial pattern in the distribution of tuber densities and can be understood from an optimal foraging perspective. PMID:16995625

  4. Movement of foraging Tundra Swans explained by spatial pattern in cryptic food densities.

    PubMed

    Klaassen, Raymond H G; Nolet, Bart A; Bankert, Daniëlle

    2006-09-01

    We tested whether Tundra Swans use information on the spatial distribution of cryptic food items (below ground Sago pondweed tubers) to shape their movement paths. In a continuous environment, swans create their own food patches by digging craters, which they exploit in several feeding bouts. Series of short (<1 m) intra-patch movements alternate with longer inter-patch movements (>1 m). Tuber biomass densities showed a positive spatial auto-correlation at a short distance (<3 m), but not at a larger distance (3-8 m). Based on the spatial pattern of the food distribution (which is assumed to be pre-harvest information for the swan) and the energy costs and benefits for different food densities at various distances, we calculated the optimal length of an inter-patch movement. A swan that moves to the patch with the highest gain rate was predicted to move to the adjacent patch (at 1 m) if the food density in the current patch had been high (>25 g/m2) and to a more distant patch (at 7-8 m) if the food density in the current patch had been low (<25 g/m2). This prediction was tested by measuring the response of swans to manipulated tuber densities. In accordance with our predictions, swans moved a long distance (>3 m) from a low-density patch and a short distance (<3 m) from a high-density patch. The quantitative agreement between prediction and observation was greater for swans feeding in pairs than for solitary swans. The result of this movement strategy is that swans visit high-density patches at a higher frequency than on offer and, consequently, achieve a 38% higher long-term gain rate. Swans also take advantage of spatial variance in food abundance by regulating the time in patches, staying longer and consuming more food from rich than from poor patches. We can conclude that the shape of the foraging path is a reflection of the spatial pattern in the distribution of tuber densities and can be understood from an optimal foraging perspective.

  5. Abnormal Ocular Movement With Executive Dysfunction and Personality Change in Subject With Thalamic Infarction: A Case Report

    PubMed Central

    Kim, Ee Jin; Kim, Myeong Ok; Kim, Chang Hwan; Joa, Kyung Lim

    2015-01-01

    The thalamus, located between the cerebrum and midbrain, is a nuclear complex connected to the cerebral cortex that influences motor skills, cognition, and mood. The thalamus is composed of 50-60 nuclei and can be divided into four areas according to vascular supply. In addition, it can be divided into five areas according to function. Many studies have reported on a thalamic infarction causing motor or sensory changes, but few have reported on behavioral and executive aspects of the ophthalmoplegia of the thalamus. This study reports a rare case of a paramedian thalamus infarction affecting the dorsomedial area of the thalamus, manifesting as oculomotor nerve palsy, an abnormal behavioral change, and executive dysfunction. This special case is presented with a review of the anatomical basis and function of the thalamus. PMID:26798620

  6. Abnormal movement of the arytenoid region during exercise presenting as exercise-induced asthma in an adolescent athlete.

    PubMed

    Bittleman, D B; Smith, R J; Weiler, J M

    1994-08-01

    A 16-year-old female basketball player presented with a 2 1/2-year history of exercise-induced severe dyspnea, stridor, and mild wheezing that did not respond to prophylactic treatment with beta-agonists and cromolyn. Spirometric data at rest were normal, but flow-volume loops during exercise suggested a variable extrathoracic obstruction. Laryngoscopic evaluation while the patient was riding an exercise bicycle demonstrated an abnormal motion of the arytenoid region causing obstruction of the airway during inspiration. The vocal cords moved normally. This patient demonstrates the capacity of supraglottic tissue to obstruct the airway during exercise as a cause for exercise-induced dyspnea and stridor. Patients with this disorder may be misdiagnosed as having exercise-induced asthma.

  7. Quantifying movement patterns for shark conservation at remote coral atolls in the Indian Ocean

    NASA Astrophysics Data System (ADS)

    Field, I. C.; Meekan, M. G.; Speed, C. W.; White, W.; Bradshaw, C. J. A.

    2011-03-01

    Grey reef sharks ( Carcharhinus amblyrhynchos) are apex predators found on many Indo-Pacific coral reefs, but little is known about their movement patterns and habitat requirements. We used acoustic telemetry to determine movements and habitat use of these sharks at the isolated Rowley Shoals atolls, 250 km off the coast of north-western Australia. We equipped 12 male and 14 female sharks ranging from 0.79 to 1.69 m in total length with transmitters that were detected by an array of 11 strategically placed receivers on two atoll reefs. Over 26,000 detections were recorded over the 325 days of receiver deployment. No sharks were observed to move between reefs. Receivers on the outer slopes of reefs provided nearly all (99%) of the detections. We found no differences in general attendance parameters due to size, sex or reef, except for maximum period of detection where larger sharks were detected over a longer period than smaller sharks. Male and female sharks were often detected at separate receivers at the outer slope habitat of one reef, suggesting sexual segregation, but this pattern did not occur at the second reef where males and females were detected at similar frequencies. We identified two patterns of daily behaviour: (1) sharks were present at the reef both day and night or (2) sharks spent more time in attendance during day than at night. Fast Fourier transforms identified 24-h cycles of attendance at the reef and a secondary peak of attendance at 12 h for most sharks, although no individuals shared the same attendance patterns. Our study provides baseline data that can be used to optimise the minimum area and habitat requirements for conservation of these apex predators.

  8. Space availability in confined sheep during pregnancy, effects in movement patterns and use of space.

    PubMed

    Averós, Xavier; Lorea, Areta; Beltrán de Heredia, Ignacia; Arranz, Josune; Ruiz, Roberto; Estevez, Inma

    2014-01-01

    Space availability is essential to grant the welfare of animals. To determine the effect of space availability on movement and space use in pregnant ewes (Ovis aries), 54 individuals were studied during the last 11 weeks of gestation. Three treatments were tested (1, 2, and 3 m2/ewe; 6 ewes/group). Ewes' positions were collected for 15 minutes using continuous scan samplings two days/week. Total and net distance, net/total distance ratio, maximum and minimum step length, movement activity, angular dispersion, nearest, furthest and mean neighbour distance, peripheral location ratio, and corrected peripheral location ratio were calculated. Restriction in space availability resulted in smaller total travelled distance, net to total distance ratio, maximum step length, and angular dispersion but higher movement activity at 1 m2/ewe as compared to 2 and 3 m2/ewe (P<0.01). On the other hand, nearest and furthest neighbour distances increased from 1 to 3 m2/ewe (P<0.001). Largest total distance, maximum and minimum step length, and movement activity, as well as lowest net/total distance ratio and angular dispersion were observed during the first weeks (P<0.05) while inter-individual distances increased through gestation. Results indicate that movement patterns and space use in ewes were clearly restricted by limitations of space availability to 1 m2/ewe. This reflected in shorter, more sinuous trajectories composed of shorter steps, lower inter-individual distances and higher movement activity potentially linked with higher restlessness levels. On the contrary, differences between 2 and 3 m2/ewe, for most variables indicate that increasing space availability from 2 to 3 m2/ewe would appear to have limited benefits, reflected mostly in a further increment in the inter-individual distances among group members. No major variations in spatial requirements were detected through gestation, except for slight increments in inter-individual distances and an initial adaptation

  9. Patterns of Gray Matter Abnormalities in Schizophrenia Based on an International Mega-analysis.

    PubMed

    Gupta, Cota Navin; Calhoun, Vince D; Rachakonda, Srinivas; Chen, Jiayu; Patel, Veena; Liu, Jingyu; Segall, Judith; Franke, Barbara; Zwiers, Marcel P; Arias-Vasquez, Alejandro; Buitelaar, Jan; Fisher, Simon E; Fernandez, Guillen; van Erp, Theo G M; Potkin, Steven; Ford, Judith; Mathalon, Daniel; McEwen, Sarah; Lee, Hyo Jong; Mueller, Bryon A; Greve, Douglas N; Andreassen, Ole; Agartz, Ingrid; Gollub, Randy L; Sponheim, Scott R; Ehrlich, Stefan; Wang, Lei; Pearlson, Godfrey; Glahn, David C; Sprooten, Emma; Mayer, Andrew R; Stephen, Julia; Jung, Rex E; Canive, Jose; Bustillo, Juan; Turner, Jessica A

    2015-09-01

    Analyses of gray matter concentration (GMC) deficits in patients with schizophrenia (Sz) have identified robust changes throughout the cortex. We assessed the relationships between diagnosis, overall symptom severity, and patterns of gray matter in the largest aggregated structural imaging dataset to date. We performed both source-based morphometry (SBM) and voxel-based morphometry (VBM) analyses on GMC images from 784 Sz and 936 controls (Ct) across 23 scanning sites in Europe and the United States. After correcting for age, gender, site, and diagnosis by site interactions, SBM analyses showed 9 patterns of diagnostic differences. They comprised separate cortical, subcortical, and cerebellar regions. Seven patterns showed greater GMC in Ct than Sz, while 2 (brainstem and cerebellum) showed greater GMC for Sz. The greatest GMC deficit was in a single pattern comprising regions in the superior temporal gyrus, inferior frontal gyrus, and medial frontal cortex, which replicated over analyses of data subsets. VBM analyses identified overall cortical GMC loss and one small cluster of increased GMC in Sz, which overlapped with the SBM brainstem component. We found no significant association between the component loadings and symptom severity in either analysis. This mega-analysis confirms that the commonly found GMC loss in Sz in the anterior temporal lobe, insula, and medial frontal lobe form a single, consistent spatial pattern even in such a diverse dataset. The separation of GMC loss into robust, repeatable spatial patterns across multiple datasets paves the way for the application of these methods to identify subtle genetic and clinical cohort effects.

  10. Residency times and patterns of movement of postbreeding dunlin on a subarctic staging area in Alaska

    USGS Publications Warehouse

    Warnock, Nils; Handel, Colleen M.; Gill, Robert E.; McCaffery, Brian J.

    2013-01-01

    Understanding how individuals use key resources is critical for effective conservation of a population. The Yukon-Kuskokwim Delta (YKD) in western Alaska is the most important postbreeding staging area for shorebirds in the subarctic North Pacific, yet little is known about movements of shorebirds there during the postbreeding period. To address this information gap, we studied residency times and patterns of movement of 17 adult and 17 juvenile radio-marked Dunlin (Calidris alpina) on the YKD between early August and early October 2005. Throughout this postbreeding period, during which Dunlin were molting, most birds were relocated within a 130 km radius of their capture site on the YKD, but three birds were relocated more than 600 km to the south at estuaries along the Alaska Peninsula. On average, juvenile Dunlin were relocated farther away from the banding site (median relocation distance = 36.3 km) than adult Dunlin (median relocation distance = 8.8 km). Post-capture, minimum lengths of stay by Dunlin on the YKD were not significantly different between juveniles (median = 19 days) and adults (median = 23 days), with some birds staging for more than 50 days. Body mass at time of capture was the best single variable explaining length of stay on the YKD, with average length of stay decreasing by 2.5 days per additional gram of body mass at time of capture. Conservation efforts for postbreeding shorebirds should consider patterns of resource use that may differ not only by age cohort but also by individual condition.

  11. Eye Movement Patterns in Natural Reading: A Comparison of Monolingual and Bilingual Reading of a Novel

    PubMed Central

    Cop, Uschi; Drieghe, Denis; Duyck, Wouter

    2015-01-01

    Introduction and Method This paper presents a corpus of sentence level eye movement parameters for unbalanced bilingual first language (L1) and second-language (L2) reading and monolingual reading of a complete novel (56 000 words). We present important sentence-level basic eye movement parameters of both bilingual and monolingual natural reading extracted from this large data corpus. Results and Conclusion Bilingual L2 reading patterns show longer sentence reading times (20%), more fixations (21%), shorter saccades (12%) and less word skipping (4.6%), than L1 reading patterns. Regression rates are the same for L1 and L2 reading. These results could indicate, analogous to a previous simulation with the E-Z reader model in the literature, that it is primarily the speeding up of lexical access that drives both L1 and L2 reading development. Bilingual L1 reading does not differ in any major way from monolingual reading. This contrasts with predictions made by the weaker links account, which predicts a bilingual disadvantage in language processing caused by divided exposure between languages. PMID:26287379

  12. Diel variation in feeding and movement patterns of juvenile Atlantic cod at offshore wind farms

    NASA Astrophysics Data System (ADS)

    Reubens, Jan T.; De Rijcke, Maarten; Degraer, Steven; Vincx, Magda

    2014-01-01

    Atlantic cod (Gadus morhua) is a commercially important fish species suffering from overexploitation in the North-East Atlantic. In recent years, their natural environment is being intensively altered by the construction of offshore wind farms in many coastal areas. These constructions form artificial reefs influencing local biodiversity and ecosystem functioning. It has been demonstrated that Atlantic cod is present in the vicinity of these constructions. However, empirical data concerning the diel activity and feeding behaviour of Atlantic cod in the vicinity of these artificial reefs is lacking. Atlantic cod has a flexible diel activity cycle linked to spatio-temporal variations in food availability and predation risk. In this study we integrated acoustic telemetry with stomach content analysis to quantify diel activity and evaluate diel feeding patterns at a windmill artificial reef (WAR) in the Belgian part of the North Sea. Atlantic cod exhibited crepuscular movements related to feeding activity; a 12 h cycle was found and the highest catch rates and stomach fullness were recorded close to sunset and sunrise. It is suggested that the observed diel movement pattern is related to the prey species community and to predation pressure. Foraging at low ambient light levels (i.e. at dusk and dawn) probably causes a trade-off between foraging success and reducing predation pressure. Fish did not leave the area in-between feeding periods. Hence other benefits (i.e. shelter against currents and predators) besides food availability stimulate the aggregation behaviour at the WARs.

  13. Arm position influences the activation patterns of trunk muscles during trunk range-of-motion movements.

    PubMed

    Siu, Aaron; Schinkel-Ivy, Alison; Drake, Janessa Dm

    2016-10-01

    To understand the activation patterns of the trunk musculature, it is also important to consider the implications of adjacent structures such as the upper limbs, and the muscles that act to move the arms. This study investigated the effects of arm positions on the activation patterns and co-activation of the trunk musculature and muscles that move the arm during trunk range-of-motion movements (maximum trunk axial twist, flexion, and lateral bend). Fifteen males and fifteen females, asymptomatic for low back pain, performed maximum trunk range-of-motion movements, with three arm positions for axial twist (loose, crossed, abducted) and two positions for flexion and lateral bend (loose, crossed). Electromyographical data were collected for eight muscles bilaterally, and activation signals were cross-correlated between trunk muscles and the muscles that move the arms (upper trapezius, latissimus dorsi). Results revealed consistently greater muscle co-activation (higher cross-correlation coefficients) between the trunk muscles and upper trapezius for the abducted arm position during maximum trunk axial twist, while results for the latissimus dorsi-trunk pairings were more dependent on the specific trunk muscles (either abdominal or back) and latissimus dorsi muscle (either right or left side), as well as the range-of-motion movement. The findings of this study contribute to the understanding of interactions between the upper limbs and trunk, and highlight the influence of arm positions on the trunk musculature. In addition, the comparison of the present results to those of individuals with back or shoulder conditions may ultimately aid in elucidating underlying mechanisms or contributing factors to those conditions.

  14. The Pattern, Geological Parameters and Distribution of Mass Movements triggered by Kashmir Earthquake 2005 in Northern Pakistan

    NASA Astrophysics Data System (ADS)

    Basharat, Muhammad; Rohn, Joachim; Baig, Shahid; Ehret, Dominik

    2010-05-01

    The Kashmir earthquake 2005 of magnitude 7.6 in Northern Pakistan triggered thousands of mass movements. These mass movements are primarily rock fall, debris fall and rock slide. The size of mass movements varies from few cubic meters to > 85 million cubic meters rock avalanches. The relationship between the active Muzaffarabad fault and mass movements shows that the concentration of mass movement is higher in hanging wall block then the footwall block. The mostly the mass movements are shallow. However the few mass movements are deep in nature. The general mass movement direction is related to southwest Himalayan thrust direction in the northeast Himalayas of Pakistan. The patterns of mass movements are concentrated close to epicenter, Main Boundary Thrust (MBT) and along the hanging wall block of the reactivated Muzaffarabad fault. The mass movements are concentrated within 14 Km wide zone of 40 Km long Muzaffarabad fault from Muzaffarabad to Chikar fault segment and 10 Km wide zone of MBT close to the epicentre. It was observed that mass movement failure generally followed 20˚-60˚ slope. The distribution of mass movements are greater in Murree Formation as compared to other formations such as Precambrian Hazara Formation, Muzaffarabad Formation, Paleocene, Eocene rock units, Panjal Formation, Tanwal Formation and granite gneisses exposed in the earthquake affected areas. The mass movements' distribution and field investigation show that these are the result of ground shaking, structural failure, hanging wall collapse, slope failure and lithological control. These parameters played the vital role during the triggering of these mass movements.

  15. Patterns of Gray Matter Abnormalities in Schizophrenia Based on an International Mega-analysis

    PubMed Central

    Gupta, Cota Navin; Calhoun, Vince D.; Rachakonda, Srinivas; Chen, Jiayu; Patel, Veena; Liu, Jingyu; Segall, Judith; Franke, Barbara; Zwiers, Marcel P.; Arias-Vasquez, Alejandro; Buitelaar, Jan; Fisher, Simon E.; Fernandez, Guillen; van Erp, Theo G. M.; Potkin, Steven; Ford, Judith; Mathalon, Daniel; McEwen, Sarah; Lee, Hyo Jong; Mueller, Bryon A.; Greve, Douglas N.; Andreassen, Ole; Agartz, Ingrid; Gollub, Randy L.; Sponheim, Scott R.; Ehrlich, Stefan; Wang, Lei; Pearlson, Godfrey; Glahn, David C.; Sprooten, Emma; Mayer, Andrew R.; Stephen, Julia; Jung, Rex E.; Canive, Jose; Bustillo, Juan; Turner, Jessica A.

    2015-01-01

    Analyses of gray matter concentration (GMC) deficits in patients with schizophrenia (Sz) have identified robust changes throughout the cortex. We assessed the relationships between diagnosis, overall symptom severity, and patterns of gray matter in the largest aggregated structural imaging dataset to date. We performed both source-based morphometry (SBM) and voxel-based morphometry (VBM) analyses on GMC images from 784 Sz and 936 controls (Ct) across 23 scanning sites in Europe and the United States. After correcting for age, gender, site, and diagnosis by site interactions, SBM analyses showed 9 patterns of diagnostic differences. They comprised separate cortical, subcortical, and cerebellar regions. Seven patterns showed greater GMC in Ct than Sz, while 2 (brainstem and cerebellum) showed greater GMC for Sz. The greatest GMC deficit was in a single pattern comprising regions in the superior temporal gyrus, inferior frontal gyrus, and medial frontal cortex, which replicated over analyses of data subsets. VBM analyses identified overall cortical GMC loss and one small cluster of increased GMC in Sz, which overlapped with the SBM brainstem component. We found no significant association between the component loadings and symptom severity in either analysis. This mega-analysis confirms that the commonly found GMC loss in Sz in the anterior temporal lobe, insula, and medial frontal lobe form a single, consistent spatial pattern even in such a diverse dataset. The separation of GMC loss into robust, repeatable spatial patterns across multiple datasets paves the way for the application of these methods to identify subtle genetic and clinical cohort effects. PMID:25548384

  16. Patterns of Gray Matter Abnormalities in Schizophrenia Based on an International Mega-analysis.

    PubMed

    Gupta, Cota Navin; Calhoun, Vince D; Rachakonda, Srinivas; Chen, Jiayu; Patel, Veena; Liu, Jingyu; Segall, Judith; Franke, Barbara; Zwiers, Marcel P; Arias-Vasquez, Alejandro; Buitelaar, Jan; Fisher, Simon E; Fernandez, Guillen; van Erp, Theo G M; Potkin, Steven; Ford, Judith; Mathalon, Daniel; McEwen, Sarah; Lee, Hyo Jong; Mueller, Bryon A; Greve, Douglas N; Andreassen, Ole; Agartz, Ingrid; Gollub, Randy L; Sponheim, Scott R; Ehrlich, Stefan; Wang, Lei; Pearlson, Godfrey; Glahn, David C; Sprooten, Emma; Mayer, Andrew R; Stephen, Julia; Jung, Rex E; Canive, Jose; Bustillo, Juan; Turner, Jessica A

    2015-09-01

    Analyses of gray matter concentration (GMC) deficits in patients with schizophrenia (Sz) have identified robust changes throughout the cortex. We assessed the relationships between diagnosis, overall symptom severity, and patterns of gray matter in the largest aggregated structural imaging dataset to date. We performed both source-based morphometry (SBM) and voxel-based morphometry (VBM) analyses on GMC images from 784 Sz and 936 controls (Ct) across 23 scanning sites in Europe and the United States. After correcting for age, gender, site, and diagnosis by site interactions, SBM analyses showed 9 patterns of diagnostic differences. They comprised separate cortical, subcortical, and cerebellar regions. Seven patterns showed greater GMC in Ct than Sz, while 2 (brainstem and cerebellum) showed greater GMC for Sz. The greatest GMC deficit was in a single pattern comprising regions in the superior temporal gyrus, inferior frontal gyrus, and medial frontal cortex, which replicated over analyses of data subsets. VBM analyses identified overall cortical GMC loss and one small cluster of increased GMC in Sz, which overlapped with the SBM brainstem component. We found no significant association between the component loadings and symptom severity in either analysis. This mega-analysis confirms that the commonly found GMC loss in Sz in the anterior temporal lobe, insula, and medial frontal lobe form a single, consistent spatial pattern even in such a diverse dataset. The separation of GMC loss into robust, repeatable spatial patterns across multiple datasets paves the way for the application of these methods to identify subtle genetic and clinical cohort effects. PMID:25548384

  17. Navigational Style Influences Eye Movement Pattern during Exploration and Learning of an Environmental Map

    PubMed Central

    Piccardi, Laura; De Luca, Maria; Nori, Raffaella; Palermo, Liana; Iachini, Fabiana; Guariglia, Cecilia

    2016-01-01

    During navigation people may adopt three different spatial styles (i.e., Landmark, Route, and Survey). Landmark style (LS) people are able to recall familiar landmarks but cannot combine them with directional information; Route style (RS) people connect landmarks to each other using egocentric information about direction; Survey style (SS) people use a map-like representation of the environment. SS individuals generally navigate better than LS and RS people. Fifty-one college students (20 LS; 17 RS, and 14 SS) took part in the experiment. The spatial cognitive style (SCS) was assessed by means of the SCS test; participants then had to learn a schematic map of a city, and after 5 min had to recall the path depicted on it. During the learning and delayed recall phases, eye-movements were recorded. Our intent was to investigate whether there is a peculiar way to explore an environmental map related to the individual’s spatial style. Results support the presence of differences in the strategy used by the three spatial styles for learning the path and its delayed recall. Specifically, LS individuals produced a greater number of fixations of short duration, while the opposite eye movement pattern characterized SS individuals. Moreover, SS individuals showed a more spread and comprehensive explorative pattern of the map, while LS individuals focused their exploration on the path and related targets. RS individuals showed a pattern of exploration at a level of proficiency between LS and SS individuals. We discuss the clinical and anatomical implications of our data. PMID:27445735

  18. Abnormal fMRI Activation Pattern during Story Listening in Individuals with Down Syndrome

    ERIC Educational Resources Information Center

    Reynolds Losin, Elizabeth A.; Rivera, Susan M.; O'Hare, Elizabeth D.; Sowell, Elizabeth R.; Pinter, Joseph D.

    2009-01-01

    Down syndrome is characterized by disproportionately severe impairments of speech and language, yet little is known about the neural underpinnings of these deficits. We compared fMRI activation patterns during passive story listening in 9 young adults with Down syndrome and 9 approximately age-matched, typically developing controls. The typically…

  19. Teachers' Knowledge of Normal and Abnormal Elimination Patterns in Elementary School Children

    ERIC Educational Resources Information Center

    Boyt, Margaret A.

    2005-01-01

    Dysfunctional elimination may be learned, to some degree. Because children spend nearly half of their waking hours at school, there is the potential for school to have a significant impact on their elimination patterns. Surveys were mailed to 1,000 randomly selected Iowa public elementary school teachers; 467 of the surveys were returned. Findings…

  20. Abnormal metabolic pattern associated with cognitive impairment in Parkinson's disease: a validation study.

    PubMed

    Meles, Sanne K; Tang, Chris C; Teune, Laura K; Dierckx, Rudi A; Dhawan, Vijay; Mattis, Paul J; Leenders, Klaus L; Eidelberg, David

    2015-09-01

    Cognitive deficits in Parkinson's disease (PD) have been associated with a specific metabolic covariance pattern. Although the expression of this PD cognition-related pattern (PDCP) correlates with neuropsychological performance, it is not known whether the PDCP topography is reproducible across PD populations. We therefore sought to identify a PDCP topography in a new sample comprised of 19 Dutch PD subjects. Network analysis of metabolic scans from these individuals revealed a significant PDCP that resembled the original network topography. Expression values for the new PDCP correlated (P=0.001) with executive dysfunction on the Frontal Assessment Battery (FAB). Subject scores for the new PDCP correlated (P<0.001) with corresponding values for the original pattern, which also correlated (P<0.005) with FAB scores in this patient group. For further validation, subject scores for the new PDCP were computed in an independent group of 86 American PD patients. In this cohort, subject scores for the new and original PDCP topographies were closely correlated (P<0.001); significant correlations between pattern expression and cognitive performance (P<0.05) were observed for both PDCP topographies. These findings suggest that the PDCP is a replicable imaging marker of PD cognitive dysfunction. PMID:26058693

  1. Curcumin prevents haloperidol-induced development of abnormal oro-facial movements: possible implications of Bcl-XL in its mechanism of action.

    PubMed

    Sookram, Christal; Tan, Mattea; Daya, Ritesh; Heffernan, Spencer; Mishra, Ram K

    2011-08-01

    Curcumin (Curcuma Longa Linn), the active component of turmeric, has been shown to be effective in ameliorating several stress and drug-induced disorders in rats and humans. However, it is unclear whether short term curcumin administration can prevent the abnormal oro-facial movements (AOFM) which develop following blockade of dopamine D2 receptors by antagonist such as Haloperidol. The objective of this study is to determine whether short term treatment with curcumin along with Haloperidol can prevent the development of AOFM in rats. Male Sprague Dawley rats were administered curcumin at 200 mg/kg, and Haloperidol at 2 mg/kg daily for 2 weeks, and AOFMs and locomotor activity were assessed at baseline, day 7 and day 14. By day 14, rats receiving concurrent curcumin administration had a significant reduction in the incidence of Haloperidol-induced AOFMs, but no change on the Haloperidol-induced hypolocomotion. There was no spiked increase in locomotor activity in absence of challenge with dopamine D2 receptor agonist. The exact mechanism by which curcumin attenuates AOFMs remains unknown, therefore, we performed a proteomic analysis of the striatal samples obtained from control and curcumin treated groups. A number of proteins were altered by curcumin, among them an antiapoptotic protein, Bcl-XL, was significantly upregulated. These results suggest that curcumin may be a promising treatment to prevent the development of AOFMs and further suggest some therapeutic value in the treatment of movement disorders. PMID:21218454

  2. Accuracy and reliability of GPS devices for measurement of movement patterns in confined spaces for court-based sports.

    PubMed

    Duffield, Rob; Reid, Machar; Baker, John; Spratford, Wayne

    2010-09-01

    The aim of this study was to assess the accuracy and reliability of global positioning system (GPS) measures of distance and speed, compared to a high-resolution motion analysis system, for confined movement patterns used in many court-based sports. A single male participant performed 10 repetitions of four respective drills replicating court-based movement patterns and six repetitions of a random movement drill that replicated tennis match-play movement patterns. Two 1Hz and two 5Hz GPS devices concurrently measured distance covered and speed of all court-based drills. A 22 camera VICON motion analysis system, operating at 100Hz, tracked the position of an 18mm reflective marker affixed to one of the GPS devices to provide the criterion movement data. Results indicated that both 1 and 5Hz GPS devices under reported distance covered as well as both mean and peak speed compared to the VICON system (P<0.05). The coefficient of variation for both GPS devices for distance and speed measures ranged between 4 and 25%. Further, the faster the speed and more repetitive the movement pattern (over a similar location), the greater the measurement error. The inter-unit reliability for distance and speed measures of both 1 and 5Hz systems for movements in confined spaces was generally low to moderate (r=0.10-0.70). In conclusion, for court-based sports or movements in confined spaces, GPS technology under reports distance covered and both mean and peak speed of movement.

  3. Home range use and movement patterns of non-native feral goats in a tropical island montane dry landscape

    USGS Publications Warehouse

    Chynoweth, Mark W.; Lepczyk, Christopher A.; Litton, Creighton M.; Hess, Steve; Kellner, James; Cordell, Susan

    2015-01-01

    Advances in wildlife telemetry and remote sensing technology facilitate studies of broad-scale movements of ungulates in relation to phenological shifts in vegetation. In tropical island dry landscapes, home range use and movements of non-native feral goats (Capra hircus) are largely unknown, yet this information is important to help guide the conservation and restoration of some of the world’s most critically endangered ecosystems. We hypothesized that feral goats would respond to resource pulses in vegetation by traveling to areas of recent green-up. To address this hypothesis, we fitted six male and seven female feral goats with Global Positioning System (GPS) collars equipped with an Argos satellite upload link to examine goat movements in relation to the plant phenology using the Normalized Difference Vegetation Index (NDVI). Movement patterns of 50% of males and 40% of females suggested conditional movement between non-overlapping home ranges throughout the year. A shift in NDVI values corresponded with movement between primary and secondary ranges of goats that exhibited long-distance movement, suggesting that vegetation phenology as captured by NDVI is a good indicator of the habitat and movement patterns of feral goats in tropical island dry landscapes. In the context of conservation and restoration of tropical island landscapes, the results of our study identify how non-native feral goats use resources across a broad landscape to sustain their populations and facilitate invasion of native plant communities.

  4. Home Range Use and Movement Patterns of Non-Native Feral Goats in a Tropical Island Montane Dry Landscape

    PubMed Central

    Chynoweth, Mark W.; Lepczyk, Christopher A.; Litton, Creighton M.; Hess, Steven C.; Kellner, James R.; Cordell, Susan

    2015-01-01

    Advances in wildlife telemetry and remote sensing technology facilitate studies of broad-scale movements of ungulates in relation to phenological shifts in vegetation. In tropical island dry landscapes, home range use and movements of non-native feral goats (Capra hircus) are largely unknown, yet this information is important to help guide the conservation and restoration of some of the world’s most critically endangered ecosystems. We hypothesized that feral goats would respond to resource pulses in vegetation by traveling to areas of recent green-up. To address this hypothesis, we fitted six male and seven female feral goats with Global Positioning System (GPS) collars equipped with an Argos satellite upload link to examine goat movements in relation to the plant phenology using the Normalized Difference Vegetation Index (NDVI). Movement patterns of 50% of males and 40% of females suggested conditional movement between non-overlapping home ranges throughout the year. A shift in NDVI values corresponded with movement between primary and secondary ranges of goats that exhibited long-distance movement, suggesting that vegetation phenology as captured by NDVI is a good indicator of the habitat and movement patterns of feral goats in tropical island dry landscapes. In the context of conservation and restoration of tropical island landscapes, the results of our study identify how non-native feral goats use resources across a broad landscape to sustain their populations and facilitate invasion of native plant communities. PMID:25807275

  5. Home range use and movement patterns of non-native feral goats in a tropical island montane dry landscape.

    PubMed

    Chynoweth, Mark W; Lepczyk, Christopher A; Litton, Creighton M; Hess, Steven C; Kellner, James R; Cordell, Susan

    2015-01-01

    Advances in wildlife telemetry and remote sensing technology facilitate studies of broad-scale movements of ungulates in relation to phenological shifts in vegetation. In tropical island dry landscapes, home range use and movements of non-native feral goats (Capra hircus) are largely unknown, yet this information is important to help guide the conservation and restoration of some of the world's most critically endangered ecosystems. We hypothesized that feral goats would respond to resource pulses in vegetation by traveling to areas of recent green-up. To address this hypothesis, we fitted six male and seven female feral goats with Global Positioning System (GPS) collars equipped with an Argos satellite upload link to examine goat movements in relation to the plant phenology using the Normalized Difference Vegetation Index (NDVI). Movement patterns of 50% of males and 40% of females suggested conditional movement between non-overlapping home ranges throughout the year. A shift in NDVI values corresponded with movement between primary and secondary ranges of goats that exhibited long-distance movement, suggesting that vegetation phenology as captured by NDVI is a good indicator of the habitat and movement patterns of feral goats in tropical island dry landscapes. In the context of conservation and restoration of tropical island landscapes, the results of our study identify how non-native feral goats use resources across a broad landscape to sustain their populations and facilitate invasion of native plant communities.

  6. Overturning conclusions of Lévy flight movement patterns by fishing boats and foraging animals.

    PubMed

    Edwards, Andrew M

    2011-06-01

    A surprisingly diverse variety of foragers have previously been concluded to exhibit movement patterns known as Lévy flights, a special type of random walk. These foragers range in size from microzooplankton in experiments to fishermen in the Pacific Ocean and the North Sea. The Lévy flight conclusion implies that all the foragers have similar scale-free movement patterns that can be described by a single dimensionless parameter, the exponent micro of a power-law (Pareto) distribution. However, the previous conclusions have been made using methods that have since been shown to be problematic: inaccurate techniques were used to estimate micro, and the power-law distribution was usually assumed to hold without testing any alternative hypotheses. Therefore, I address the open question of whether the previous data still support the Lévy flight hypothesis, and thus determine whether Lévy flights really are so ubiquitous in ecology. I present a comprehensive reanalysis of 17 data sets from seven previous studies for which Lévy flight behavior had been concluded, covering marine, terrestrial, and experimental systems from four continents. I use the modern likelihood and Akaike weights approach to test whether simple alternative models are more supported by the data than Lévy flights. The previously estimated values of the power-law exponent micro do not match those calculated here using the accurate likelihood approach, and almost all of them lie outside of the likelihood-based 95% confidence intervals. Furthermore, the original power-law Lévy flight model is overwhelmingly rejected for 16 out of the 17 data sets when tested against three other simple models. For one data set, the data are consistent with coming from a bounded power-law distribution (a truncated Lévy flight). For three other data sets, an exponential distribution corresponding to a simple Poisson process is suitable. Thus, Lévy flight movement patterns are not the common phenomena that was once

  7. Overturning conclusions of Lévy flight movement patterns by fishing boats and foraging animals.

    PubMed

    Edwards, Andrew M

    2011-06-01

    A surprisingly diverse variety of foragers have previously been concluded to exhibit movement patterns known as Lévy flights, a special type of random walk. These foragers range in size from microzooplankton in experiments to fishermen in the Pacific Ocean and the North Sea. The Lévy flight conclusion implies that all the foragers have similar scale-free movement patterns that can be described by a single dimensionless parameter, the exponent micro of a power-law (Pareto) distribution. However, the previous conclusions have been made using methods that have since been shown to be problematic: inaccurate techniques were used to estimate micro, and the power-law distribution was usually assumed to hold without testing any alternative hypotheses. Therefore, I address the open question of whether the previous data still support the Lévy flight hypothesis, and thus determine whether Lévy flights really are so ubiquitous in ecology. I present a comprehensive reanalysis of 17 data sets from seven previous studies for which Lévy flight behavior had been concluded, covering marine, terrestrial, and experimental systems from four continents. I use the modern likelihood and Akaike weights approach to test whether simple alternative models are more supported by the data than Lévy flights. The previously estimated values of the power-law exponent micro do not match those calculated here using the accurate likelihood approach, and almost all of them lie outside of the likelihood-based 95% confidence intervals. Furthermore, the original power-law Lévy flight model is overwhelmingly rejected for 16 out of the 17 data sets when tested against three other simple models. For one data set, the data are consistent with coming from a bounded power-law distribution (a truncated Lévy flight). For three other data sets, an exponential distribution corresponding to a simple Poisson process is suitable. Thus, Lévy flight movement patterns are not the common phenomena that was once

  8. Water movement monitoring in a boreal patterned fen peatland using an isotopic approach

    NASA Astrophysics Data System (ADS)

    Carrer, G.; Rousseau, A. N.; St-Hilaire, A.; Fossey, M.; Jutras, S.

    2011-12-01

    Patterned peatlands occupy a large portion of the Northen boreal region of Quebec, Canada. An obvious characteristic of peatlands is their great capacity to retain water. Indeed, a peatland may contain more than 70% of its volume in water. However, the rapid decrease of permeability with depth in peat soils suggests that a major part of the aquifer does not substantially contribute to the overall water movement and ensuing outflow. Given the current state of knowledge about these ecosystems, three questions can be formulated: (i) How does the water flow in patterned peatlands (piston flow, surface runoff)? (ii) Is there any mixing of water in the pools that may change the isotopic signal? (iii) Can the isotopic signal help identifying the origin of the water? To answer these questions, natural tracers (2H, 18O, DOC) and physical parameters (conductivity, temperature) are monitored in a patterned fen located in the Northern boreal region of Quebec. Preliminary results show that the summer flow is superficial and corresponds to a "piston flow"; and there is very little mixing of the water in the pools. However, because the isotopic signal is not uniform, it is difficult to separate the hydrograph and, thus, determine the various origins of the water.

  9. Spatial patterns of neuronal activity in rat cerebral cortex during non-rapid eye movement sleep.

    PubMed

    Wanger, Tim; Wetzel, Wolfram; Scheich, Henning; Ohl, Frank W; Goldschmidt, Jürgen

    2015-11-01

    It is commonly assumed that cortical activity in non-rapid eye movement sleep (NREMS) is spatially homogeneous on the mesoscopic scale. This is partly due to the limited observational scope of common metabolic or imaging methods in sleep. We used the recently developed technique of thallium-autometallography (TlAMG) to visualize mesoscopic patterns of activity in the sleeping cortex with single-cell resolution. We intravenously injected rats with the lipophilic chelate complex thallium diethyldithiocarbamate (TlDDC) during spontaneously occurring periods of NREMS and mapped the patterns of neuronal uptake of the potassium (K+) probe thallium (Tl+). Using this method, we show that cortical activity patterns are not spatially homogeneous during discrete 5-min episodes of NREMS in unrestrained rats-rather, they are complex and spatially diverse. Along with a relative predominance of infragranular layer activation, we find pronounced differences in metabolic activity of neighboring neuronal assemblies, an observation which lends support to the emerging paradigm that sleep is a distributed process with regulation on the local scale.

  10. Differential Annual Movement Patterns in a Migratory Species: Effects of Experience and Sexual Maturation

    PubMed Central

    Jorge, Paulo E.; Sowter, David; Marques, Paulo A. M.

    2011-01-01

    Some animals migrate long distances to exploit important seasonal food resources in the northern regions of the northern hemisphere, whilst avoiding winter starvation. Changes in the individual's age and navigational skills are likely to affect migration, which in turn influences the geographic distribution of individuals. Processes such as sexual maturation and navigational abilities are affected by age, and age is thus a key factor in understanding migration patterns and differences in distribution ranges. In the present study, we investigated the effects of age on the geographic distribution of a population of Lesser Black-backed Gulls Larus fuscus throughout its annual cycle, by analyzing a dataset of 19,096 records from 10,000 color-ringed gulls. In contrast to previous assumptions, the results showed that gulls were geographically segregated by age throughout the entire annual cycle, rather than showing a geographic age-related cline only in the wintering areas. This asymmetric distribution results from a reduction in the annual range of sexually mature gulls, and the differential distribution of mature and immature individuals (mature birds remained in more northern areas, compared to immature birds, throughout the annual cycle). Furthermore, although immature gulls travelled longer distances than adults, they initiated their fall migration with short movements, in contrast to adults that migrated using longer movements. The effects identified in this study explain the non-homogenous distribution of populations throughout the annual cycle, with wide implications for the development of effective human health policies and/or wildlife management strategies. PMID:21799853

  11. [Coordination patterns assessed by a continuous measure of joints coupling during upper limb repetitive movements].

    PubMed

    Draicchio, F; Silvetti, A; Ranavolo, A; Iavicoli, S

    2008-01-01

    We analyzed the coordination patterns between elbow, shoulder and trunk in a motor task consisting of reaching out, picking up a cylinder, and transporting it back by using the Dynamical Systems Theory and calculating the continuous relative phase (CRP), a continuous measure of the coupling between two interacting joints. We used an optoelectronic motion analysis system consisting of eight infra-red ray cameras to detect the movements of nine skin-mounted markers. We calculated the root square of the adjusted coefficient of determination, the coefficient of multiple correlation (CMC), in order to investigate the repeatability of the joints coordination. The data confirm that the CNS establishes both synergic (i.e. coupling between shoulder and trunk on the frontal plane) and hierarchical (i.e. coupling between elbow-shoulder-trunk on the horizontal plane) relationships among the available degrees of freedom to overcome the complexity due to motor redundancy. The present study describes a method to investigate the organization of the kinematic degrees of freedom during upper limb multi-joint motor tasks that can be useful to assess upper limb repetitive movements.

  12. Unraveling Markov Processes in Movement Patterns of Indicator Species in Response to Chemical Stressors

    NASA Astrophysics Data System (ADS)

    Nguyen, Tuyen Van; Liu, Yuedan; Jung, Il-Hyo; Chon, Tae-Soo; Lee, Sang-Hee

    Revealing biological responses of organisms in responding to environmental stressors is the critical issue in contemporary ecological sciences. Markov processes in behavioral data were unraveled by utilizing the hidden Markov model (HMM). Individual organisms of daphnia (Daphnia magna) and zebrafish (Danio rerio) were exposed to diazinon at low concentrations. The transition probability matrix (TPM) and the emission probability matrix (EPM) were accordingly estimated by training with the HMM and were verified before and after the treatments with 10-6 tolerance in 103 iterations. Structured property in behavioral changes was accordingly revealed to characterize dynamic processes in movement patterns. Parameters and sequences produced through the HMM training could be a suitable means of monitoring toxic chemicals in environment.

  13. Abnormal luteinizing hormone response patterns to synthetic gonadotrophin releasing hormone in patients with polycystic ovarian syndrome.

    PubMed

    Katz, M; Carr, P J

    1976-08-01

    Basal gonadotrophin and sex steroid levels and responses to an intravenous injection of 100 mug gonadotrophin releasing hormone (Gn-RH) have been studied in 15 patients with polycystic ovaries. Mean basal LH concentration was raised and an excessive, exaggerated and prolonged response was observed after Gn-RH treatment, but patients could further be subdivided into two functional groups on the basis of their basal LH values and LH response patterns. Evidence was also produced which suggested a breakdown in the negative feedback mechanism in these patients.

  14. Movement patterns in a partial migrant: a multi-event capture-recapture approach.

    PubMed

    Gourlay-Larour, Marie-Lucile; Pradel, Roger; Guillemain, Matthieu; Guitton, Jean-Sébastien; L'Hostis, Monique; Santin-Janin, Hugues; Caizergues, Alain

    2014-01-01

    Partial migration is a pervasive albeit poorly studied phenomenon by which some individuals of a population migrate while others are residents. It has tremendous consequences on seasonal variations of population size/structure and therefore management. Using a multi-event capture-mark-recapture/recovery (CMR) approach, we assessed seasonal site occupancy, survival and site fidelity of a partially migratory diving duck, the Common pochard (Aythya ferina), in an area potentially including both local breeders and winter visitors. The modelling exercise indeed discriminated two different categories of individuals. First, locally breeding females which had a probability of being present in our study area during winter of 0.41. Females of this category were found to be more faithful to their breeding site than males (breeding site fidelity probabilities of 1 and 0.11, respectively). The second category of birds were winter visitors, which included adults of both sexes, whose probability of being present in the study area during the breeding season was nil, and young of both sexes with a 0.11 probability of being present in the area during the breeding season. All wintering individuals, among which there was virtually no locally breeding male, displayed a high fidelity to our study area from one winter to the next (0.41-0.43). Estimated annual survival rates differed according to age (adults 0.69, young 0.56). For both age classes mortality was higher during late winter/early spring than during summer/early winter. Our study is among the first to show how and under which conditions the multi-event approach can be employed for investigating complex movement patterns encountered in partial migrants, providing a convenient tool for overcoming state uncertainty. It also shows why studying patterns of probability of individual presence/movements in partial migrants is a key towards understanding seasonal variations in numbers. PMID:24802936

  15. Incorporating movement patterns to improve survival estimates for juvenile bull trout

    USGS Publications Warehouse

    Bowerman, Tracy; Budy, Phaedra

    2012-01-01

    Populations of many fish species are sensitive to changes in vital rates during early life stages, but our understanding of the factors affecting growth, survival, and movement patterns is often extremely limited for juvenile fish. These critical information gaps are particularly evident for bull trout Salvelinus confluentus, a threatened Pacific Northwest char. We combined several active and passive mark–recapture and resight techniques to assess migration rates and estimate survival for juvenile bull trout (70–170 mm total length). We evaluated the relative performance of multiple survival estimation techniques by comparing results from a common Cormack–Jolly–Seber (CJS) model, the less widely used Barker model, and a simple return rate (an index of survival). Juvenile bull trout of all sizes emigrated from their natal habitat throughout the year, and thereafter migrated up to 50 km downstream. With the CJS model, high emigration rates led to an extreme underestimate of apparent survival, a combined estimate of site fidelity and survival. In contrast, the Barker model, which allows survival and emigration to be modeled as separate parameters, produced estimates of survival that were much less biased than the return rate. Estimates of age-class-specific annual survival from the Barker model based on all available data were 0.218±0.028 (estimate±SE) for age-1 bull trout and 0.231±0.065 for age-2 bull trout. This research demonstrates the importance of incorporating movement patterns into survival analyses, and we provide one of the first field-based estimates of juvenile bull trout annual survival in relatively pristine rearing conditions. These estimates can provide a baseline for comparison with future studies in more impacted systems and will help managers develop reliable stage-structured population models to evaluate future recovery strategies.

  16. Movement patterns in a partial migrant: a multi-event capture-recapture approach.

    PubMed

    Gourlay-Larour, Marie-Lucile; Pradel, Roger; Guillemain, Matthieu; Guitton, Jean-Sébastien; L'Hostis, Monique; Santin-Janin, Hugues; Caizergues, Alain

    2014-01-01

    Partial migration is a pervasive albeit poorly studied phenomenon by which some individuals of a population migrate while others are residents. It has tremendous consequences on seasonal variations of population size/structure and therefore management. Using a multi-event capture-mark-recapture/recovery (CMR) approach, we assessed seasonal site occupancy, survival and site fidelity of a partially migratory diving duck, the Common pochard (Aythya ferina), in an area potentially including both local breeders and winter visitors. The modelling exercise indeed discriminated two different categories of individuals. First, locally breeding females which had a probability of being present in our study area during winter of 0.41. Females of this category were found to be more faithful to their breeding site than males (breeding site fidelity probabilities of 1 and 0.11, respectively). The second category of birds were winter visitors, which included adults of both sexes, whose probability of being present in the study area during the breeding season was nil, and young of both sexes with a 0.11 probability of being present in the area during the breeding season. All wintering individuals, among which there was virtually no locally breeding male, displayed a high fidelity to our study area from one winter to the next (0.41-0.43). Estimated annual survival rates differed according to age (adults 0.69, young 0.56). For both age classes mortality was higher during late winter/early spring than during summer/early winter. Our study is among the first to show how and under which conditions the multi-event approach can be employed for investigating complex movement patterns encountered in partial migrants, providing a convenient tool for overcoming state uncertainty. It also shows why studying patterns of probability of individual presence/movements in partial migrants is a key towards understanding seasonal variations in numbers.

  17. Movement Patterns in a Partial Migrant: A Multi-Event Capture-Recapture Approach

    PubMed Central

    Gourlay-Larour, Marie-Lucile; Pradel, Roger; Guillemain, Matthieu; Guitton, Jean-Sébastien; L'Hostis, Monique; Santin-Janin, Hugues; Caizergues, Alain

    2014-01-01

    Partial migration is a pervasive albeit poorly studied phenomenon by which some individuals of a population migrate while others are residents. It has tremendous consequences on seasonal variations of population size/structure and therefore management. Using a multi-event capture-mark-recapture/recovery (CMR) approach, we assessed seasonal site occupancy, survival and site fidelity of a partially migratory diving duck, the Common pochard (Aythya ferina), in an area potentially including both local breeders and winter visitors. The modelling exercise indeed discriminated two different categories of individuals. First, locally breeding females which had a probability of being present in our study area during winter of 0.41. Females of this category were found to be more faithful to their breeding site than males (breeding site fidelity probabilities of 1 and 0.11, respectively). The second category of birds were winter visitors, which included adults of both sexes, whose probability of being present in the study area during the breeding season was nil, and young of both sexes with a 0.11 probability of being present in the area during the breeding season. All wintering individuals, among which there was virtually no locally breeding male, displayed a high fidelity to our study area from one winter to the next (0.41–0.43). Estimated annual survival rates differed according to age (adults 0.69, young 0.56). For both age classes mortality was higher during late winter/early spring than during summer/early winter. Our study is among the first to show how and under which conditions the multi-event approach can be employed for investigating complex movement patterns encountered in partial migrants, providing a convenient tool for overcoming state uncertainty. It also shows why studying patterns of probability of individual presence/movements in partial migrants is a key towards understanding seasonal variations in numbers. PMID:24802936

  18. Mice with Dab1 or Vldlr insufficiency exhibit abnormal neonatal vocalization patterns

    PubMed Central

    Fraley, E. R.; Burkett, Z. D.; Day, N. F.; Schwartz, B. A.; Phelps, P. E.; White, S. A.

    2016-01-01

    Genetic and epigenetic changes in components of the Reelin-signaling pathway (RELN, DAB1) are associated with autism spectrum disorder (ASD) risk. Social communication deficits are a key component of the ASD diagnostic criteria, but the underlying neurogenetic mechanisms remain unknown. Reln insufficient mice exhibit ASD-like behavioral phenotypes including altered neonatal vocalization patterns. Reelin affects multiple pathways including through the receptors, Very low-density lipoprotein receptor (Vldlr), Apolipoprotein receptor 2 (Apoer2), and intracellular signaling molecule Disabled-1 (Dab1). As Vldlr was previously implicated in avian vocalization, here we investigate vocalizations of neonatal mice with a reduction or absence of these components of the Reelin-signaling pathway. Mice with low or no Dab1 expression exhibited reduced calling rates, altered call-type usage, and differential vocal development trajectories. Mice lacking Vldlr expression also had altered call repertoires, and this effect was exacerbated by deficiency in Apoer2. Together with previous findings, these observations 1) solidify a role for Reelin in vocal communication of multiple species, 2) point to the canonical Reelin-signaling pathway as critical for development of normal neonatal calling patterns in mice, and 3) suggest that mutants in this pathway could be used as murine models for Reelin-associated vocal deficits in humans. PMID:27184477

  19. Spreading photoparoxysmal EEG response is associated with an abnormal cortical excitability pattern.

    PubMed

    Siniatchkin, Michael; Groppa, Sergey; Jerosch, Bettina; Muhle, Hiltrud; Kurth, Christoph; Shepherd, Alex J; Siebner, Hartwig; Stephani, Ulrich

    2007-01-01

    Photosensitivity or photoparoxysmal response (PPR) is a highly heritable electroencephalographic trait characterized by an abnormal cortical response to intermittent photic stimulation (IPS). In PPR-positive individuals, IPS induces spikes, spike-waves or intermittent slow waves. The PPR may be restricted to posterior visual areas (i.e. local PPR with occipital spikes only) or spread to anterior non-visual cortical regions (i.e. PPR with propagation). The mechanisms underlying the PPR and causing its spread remain to be clarified. In unmedicated PPR-positive individuals and PPR-negative control participants without any history of previous seizures, we used focal transcranial magnetic stimulation (TMS) to investigate the excitability of the visual or primary motor cortex (M1). In the first experiment [18 healthy control subjects (i.e. without PPR in electroencephalography: 6 females, mean age 26.5 +/- 7.34 years) and 17 healthy participants with PPR (7 females, mean age 25.18 +/- 12.2 years) were studied], occipital TMS was used to elicit phosphenes or to suppress the visual perception of letter trigrams. PPR-positive individuals with propagation had lower phosphene thresholds and steeper stimulus-response curves than individuals without PPR or with occipital spikes only. Occipital TMS also induced a stronger suppression of visual perception in PPR-positive subjects with propagation relative to subjects without PPR or with occipital spikes. In the second experiment, we applied TMS over the right M1 without concurrent IPS and measured the motor threshold, the stimulus response curve, and the duration of the cortical silent period (CSP) in PPR positive individuals with propagation and in PPR-negative control participants [15 right-handed healthy subjects without PPR (3 males, mean age 17.7 +/- 3.6 years) and 14 right-handed healthy individuals showing a PPR with propagation (3 males, mean age 17.4 +/- 3.9 years)]. PPR-positive individuals showed no changes in these

  20. How do cancer patients navigate the public information environment? Understanding patterns and motivations for movement among information sources.

    PubMed

    Nagler, Rebekah H; Romantan, Anca; Kelly, Bridget J; Stevens, Robin S; Gray, Stacy W; Hull, Shawnika J; Ramirez, A Susana; Hornik, Robert C

    2010-09-01

    Little is known about how patients move among information sources to fulfill unmet needs. We interviewed 43 breast, prostate, and colorectal cancer patients. Using a grounded theory approach, we identified patterns and motivations for movement among information sources. Overall, patients reported using one source (e.g., newspaper) followed by the use of another source (e.g., Internet), and five key motivations for such cross-source movement emerged. Patients' social networks often played a central role in this movement. Understanding how patients navigate an increasingly complex information environment may help clinicians and educators to guide patients to appropriate, high-quality sources.

  1. Disparity in population structuring of Southwestern Willow Flycatchers based on geographic distance, movement patterns, and genetic analyses.

    PubMed

    Stumpf, Katie J; Theimer, Tad C; McLeod, Mary Anne; Koronkiewicz, Thomas J

    2014-12-01

    Estimates of population connectivity often are based on demographic analysis of movements among subpopulations, but this approach may fail to detect rare migrants or overestimate the contribution of movements into populations when migrants fail to successfully reproduce. We compared movement data of endangered Southwestern Willow Flycatchers among isolated populations in Nevada and Arizona from 1997 to 2008 to genetic analyses of samples collected between 2004 and 2008 to determine the degree to which these two methods were concordant in their estimates of population structuring. Given that documented movements of 13 color-banded adults and 23 juveniles over 10 years indicated low rates of long-distance movements, we predicted that genetic analyses would show significant population structuring between a northern (Nevada) deme and a southern (Arizona) deme. We genotyped 93 adult individuals at seven microsatellite loci and used two Bayesian clustering programs, STRUCTURE and GENELAND, to predict population structure. Both clustering algorithms produced the same structuring pattern; a cluster containing birds breeding in Pahranagat National Wildlife Refuge, the northern-most Nevada site, and a cluster comprised of all other populations. These results highlight that estimates of subpopulation connectivity based on demographic analyses may differ from those based on genetics, suggesting either temporal changes in the pattern of movements, the importance of undetected movements, or differential contribution of migrants to the subpopulations they enter.

  2. Diel and seasonal movement pattern of the dusky grouper Epinephelus marginatus inside a marine reserve.

    PubMed

    Koeck, Barbara; Pastor, Jérémy; Saragoni, Gilles; Dalias, Nicolas; Payrot, Jérôme; Lenfant, Philippe

    2014-03-01

    Temporal movement patterns and spawning behaviour of the dusky grouper Epinephelus marginatus were investigated using depth and temperature sensors combined to acoustic telemetry. Results showed that these fish are year-round resident, remaining inside the fully protected area of the marine reserve of Cerbère-Banyuls (65 ha) and display a diurnal activity pattern. Records from depth sensors revealed that groupers range inside small, distinct, and individual territories. Individual variations in habitat depth are only visible on a seasonal scale, i.e., between the spawning season and the rest of the year. In fact, during summer months when the seawater temperature exceeded 20 °C, tagged groupers made vertical spawning migrations of 4-8 m in amplitude. These vertical migrations are characteristic of the reproductive behaviour of dusky groupers, during which they release their gametes. The results are notable for the implementation of management rules in marine protected areas, such as reduced navigation speed, boating or attendance during spawning season. PMID:24361257

  3. Interocular suppression patterns in binocularly abnormal observers using luminance- and contrast-modulated noise stimuli.

    PubMed

    Chima, Akash S; Formankiewicz, Monika A; Waugh, Sarah J

    2016-08-01

    In binocular viewing, images presented to the amblyopic eye are suppressed in the cortex to prevent confusion or diplopia. The present study measures depth and extent of interocular suppression across the central circular 24° visual field in observers with strabismus and microstrabismus. Visual stimuli were concentric rings of alternating polarity, each divided into sectors. Rings were defined by luminance (L), luminance-modulated noise (LM), or contrast-modulated noise (CM). They were viewed binocularly except for the tested ring, which was viewed dichoptically, so that the modulation of one sector presented to the weaker or amblyopic eye was adjusted to perceptually match the surrounding ring presented to the preferred eye. A two alternative forced-choice paradigm combined with a staircase procedure allowed for measurement of the point of subjective equality, or perceptual match. Depth of suppression was calculated as the difference between physical modulations presented to the two eyes at this point. Strabismic participants showed suppression deeper centrally than peripherally, and in one hemifield of the visual field more than the other. Suppression was deeper for L than LM, and CM than LM stimuli. Microstrabismic suppression was weaker than that of strabismics, central for L and LM stimuli, with suppression of CM stimuli being broader, deeper and more in one hemifield. Suppression depth was positively correlated with interocular visual acuity difference and stereoacuity reduction. Clinically, LM stimuli could be used for assessment of deeper amblyopes to assess suppression patterns, while more sensitive detection of mild suppression would be possible using CM stimuli.

  4. Interocular suppression patterns in binocularly abnormal observers using luminance- and contrast-modulated noise stimuli.

    PubMed

    Chima, Akash S; Formankiewicz, Monika A; Waugh, Sarah J

    2016-08-01

    In binocular viewing, images presented to the amblyopic eye are suppressed in the cortex to prevent confusion or diplopia. The present study measures depth and extent of interocular suppression across the central circular 24° visual field in observers with strabismus and microstrabismus. Visual stimuli were concentric rings of alternating polarity, each divided into sectors. Rings were defined by luminance (L), luminance-modulated noise (LM), or contrast-modulated noise (CM). They were viewed binocularly except for the tested ring, which was viewed dichoptically, so that the modulation of one sector presented to the weaker or amblyopic eye was adjusted to perceptually match the surrounding ring presented to the preferred eye. A two alternative forced-choice paradigm combined with a staircase procedure allowed for measurement of the point of subjective equality, or perceptual match. Depth of suppression was calculated as the difference between physical modulations presented to the two eyes at this point. Strabismic participants showed suppression deeper centrally than peripherally, and in one hemifield of the visual field more than the other. Suppression was deeper for L than LM, and CM than LM stimuli. Microstrabismic suppression was weaker than that of strabismics, central for L and LM stimuli, with suppression of CM stimuli being broader, deeper and more in one hemifield. Suppression depth was positively correlated with interocular visual acuity difference and stereoacuity reduction. Clinically, LM stimuli could be used for assessment of deeper amblyopes to assess suppression patterns, while more sensitive detection of mild suppression would be possible using CM stimuli. PMID:27580040

  5. A Comparison of Spatial and Movement Patterns between Sympatric Predators: Bull Sharks (Carcharhinus leucas) and Atlantic Tarpon (Megalops atlanticus)

    PubMed Central

    Hammerschlag, Neil; Luo, Jiangang; Irschick, Duncan J.; Ault, Jerald S.

    2012-01-01

    Background Predators can impact ecosystems through trophic cascades such that differential patterns in habitat use can lead to spatiotemporal variation in top down forcing on community dynamics. Thus, improved understanding of predator movements is important for evaluating the potential ecosystem effects of their declines. Methodology/Principal Findings We satellite-tagged an apex predator (bull sharks, Carcharhinus leucas) and a sympatric mesopredator (Atlantic tarpon, Megalops atlanticus) in southern Florida waters to describe their habitat use, abundance and movement patterns. We asked four questions: (1) How do the seasonal abundance patterns of bull sharks and tarpon compare? (2) How do the movement patterns of bull sharks and tarpon compare, and what proportion of time do their respective primary ranges overlap? (3) Do tarpon movement patterns (e.g., straight versus convoluted paths) and/or their rates of movement (ROM) differ in areas of low versus high bull shark abundance? and (4) Can any general conclusions be reached concerning whether tarpon may mitigate risk of predation by sharks when they are in areas of high bull shark abundance? Conclusions/Significance Despite similarities in diet, bull sharks and tarpon showed little overlap in habitat use. Bull shark abundance was high year-round, but peaked in winter; while tarpon abundance and fishery catches were highest in late spring. However, presence of the largest sharks (>230 cm) coincided with peak tarpon abundance. When moving over deep open waters (areas of high shark abundance and high food availability) tarpon maintained relatively high ROM in directed lines until reaching shallow structurally-complex areas. At such locations, tarpon exhibited slow tortuous movements over relatively long time periods indicative of foraging. Tarpon periodically concentrated up rivers, where tracked bull sharks were absent. We propose that tarpon trade-off energetic costs of both food assimilation and osmoregulation

  6. Population Characteristics and Seasonal Movement Patterns of the Rattlesnake Hills Elk Herd - Status Report 2000

    SciTech Connect

    Tiller, Brett L; Cadwell, Larry L; Zufelt, Rhett K; Turner, Scott D; Turner, Gerald K

    2000-10-10

    Wildlife biologists documented an isolated elk population in 1972 on the U.S. Department of Energy's (DOE) Hanford Site. Since then the herd has grown, exceeding 800 animals in 1999. Limited harvests on adjacent private lands have occurred since 1986. The large herd size coupled with limited annual harvest have increased concerns about private land crop damages, vehicle collisions, degradation of the native environment, and the herd's use of radiologically controlled areas on the Hanford Site. As a result, in 1999, a decision was made by the Washington Department of Fish and Wildlife (WDFW) (animal management), the U.S. Fish and Wildlife Service (USFWS) (land management), and DOE (landowner) to conduct a large-scale animal roundup to remove elk from the DOE-owned lands and relocate them to distant areas within Washington State. The interagency roundup and relocation occurred in spring 2000. This report presents the current status of the herd size and composition, annual removal estimates, and some limited seasonal area-use patterns by several radio-collared elk subsequent to the large-scale elk roundup. The elk herd maintained an approximate 25% annual increase until 2000. A large harvest offsite in 1999 coupled with the large-scale roundup in spring 2000 reduced herd size to the current estimate of 660 animals. As of August 2000, the herd consisted of 287 (43%) males, 282 (42%) females, and 91 (13%) calves. There has been a notable cycling of calf recruitment rates throughout the 1990s and in 2000. Elk home-range estimates revealed a substantial decrease in summer home ranges in 2000, presumably, in part, as a result of the summer 2000 Hanford Site wildfire. Movement analysis also determined that, as population size increased, so has the frequency and extent of the animals' offsite movements, particularly on private lands adjacent to the Hanford Site in both spring and summer seasons. The frequency and duration of movements by male elk onto the central portions of

  7. The Movement- and Load-Dependent Differences in the EMG Patterns of the Human Arm Muscles during Two-Joint Movements (A Preliminary Study)

    PubMed Central

    Tomiak, Tomasz; Abramovych, Tetiana I.; Gorkovenko, Andriy V.; Vereshchaka, Inna V.; Mishchenko, Viktor S.; Dornowski, Marcin; Kostyukov, Alexander I.

    2016-01-01

    Slow circular movements of the hand with a fixed wrist joint that were produced in a horizontal plane under visual guidance during conditions of action of the elastic load directed tangentially to the movement trajectory were studied. The positional dependencies of the averaged surface EMGs in the muscles of the elbow and shoulder joints were compared for four possible combinations in the directions of load and movements. The EMG intensities were largely correlated with the waves of the force moment computed for a corresponding joint in the framework of a simple geometrical model of the system: arm - experimental setup. At the same time, in some cases the averaged EMGs exit from the segments of the trajectory restricted by the force moment singular points (FMSPs), in which the moments exhibited altered signs. The EMG activities display clear differences for the eccentric and concentric zones of contraction that are separated by the joint angle singular points (JASPs), which present extreme at the joint angle traces. We assumed that the modeled patterns of FMSPs and JASPs may be applied for an analysis of the synergic interaction between the motor commands arriving at different muscles in arbitrary two-joint movements. PMID:27375496

  8. Real-Time Subject-Independent Pattern Classification of Overt and Covert Movements from fNIRS Signals.

    PubMed

    Robinson, Neethu; Zaidi, Ali Danish; Rana, Mohit; Prasad, Vinod A; Guan, Cuntai; Birbaumer, Niels; Sitaram, Ranganatha

    2016-01-01

    Recently, studies have reported the use of Near Infrared Spectroscopy (NIRS) for developing Brain-Computer Interface (BCI) by applying online pattern classification of brain states from subject-specific fNIRS signals. The purpose of the present study was to develop and test a real-time method for subject-specific and subject-independent classification of multi-channel fNIRS signals using support-vector machines (SVM), so as to determine its feasibility as an online neurofeedback system. Towards this goal, we used left versus right hand movement execution and movement imagery as study paradigms in a series of experiments. In the first two experiments, activations in the motor cortex during movement execution and movement imagery were used to develop subject-dependent models that obtained high classification accuracies thereby indicating the robustness of our classification method. In the third experiment, a generalized classifier-model was developed from the first two experimental data, which was then applied for subject-independent neurofeedback training. Application of this method in new participants showed mean classification accuracy of 63% for movement imagery tasks and 80% for movement execution tasks. These results, and their corresponding offline analysis reported in this study demonstrate that SVM based real-time subject-independent classification of fNIRS signals is feasible. This method has important applications in the field of hemodynamic BCIs, and neuro-rehabilitation where patients can be trained to learn spatio-temporal patterns of healthy brain activity. PMID:27467528

  9. Real-Time Subject-Independent Pattern Classification of Overt and Covert Movements from fNIRS Signals

    PubMed Central

    Rana, Mohit; Prasad, Vinod A.; Guan, Cuntai; Birbaumer, Niels; Sitaram, Ranganatha

    2016-01-01

    Recently, studies have reported the use of Near Infrared Spectroscopy (NIRS) for developing Brain–Computer Interface (BCI) by applying online pattern classification of brain states from subject-specific fNIRS signals. The purpose of the present study was to develop and test a real-time method for subject-specific and subject-independent classification of multi-channel fNIRS signals using support-vector machines (SVM), so as to determine its feasibility as an online neurofeedback system. Towards this goal, we used left versus right hand movement execution and movement imagery as study paradigms in a series of experiments. In the first two experiments, activations in the motor cortex during movement execution and movement imagery were used to develop subject-dependent models that obtained high classification accuracies thereby indicating the robustness of our classification method. In the third experiment, a generalized classifier-model was developed from the first two experimental data, which was then applied for subject-independent neurofeedback training. Application of this method in new participants showed mean classification accuracy of 63% for movement imagery tasks and 80% for movement execution tasks. These results, and their corresponding offline analysis reported in this study demonstrate that SVM based real-time subject-independent classification of fNIRS signals is feasible. This method has important applications in the field of hemodynamic BCIs, and neuro-rehabilitation where patients can be trained to learn spatio-temporal patterns of healthy brain activity. PMID:27467528

  10. Real-Time Subject-Independent Pattern Classification of Overt and Covert Movements from fNIRS Signals.

    PubMed

    Robinson, Neethu; Zaidi, Ali Danish; Rana, Mohit; Prasad, Vinod A; Guan, Cuntai; Birbaumer, Niels; Sitaram, Ranganatha

    2016-01-01

    Recently, studies have reported the use of Near Infrared Spectroscopy (NIRS) for developing Brain-Computer Interface (BCI) by applying online pattern classification of brain states from subject-specific fNIRS signals. The purpose of the present study was to develop and test a real-time method for subject-specific and subject-independent classification of multi-channel fNIRS signals using support-vector machines (SVM), so as to determine its feasibility as an online neurofeedback system. Towards this goal, we used left versus right hand movement execution and movement imagery as study paradigms in a series of experiments. In the first two experiments, activations in the motor cortex during movement execution and movement imagery were used to develop subject-dependent models that obtained high classification accuracies thereby indicating the robustness of our classification method. In the third experiment, a generalized classifier-model was developed from the first two experimental data, which was then applied for subject-independent neurofeedback training. Application of this method in new participants showed mean classification accuracy of 63% for movement imagery tasks and 80% for movement execution tasks. These results, and their corresponding offline analysis reported in this study demonstrate that SVM based real-time subject-independent classification of fNIRS signals is feasible. This method has important applications in the field of hemodynamic BCIs, and neuro-rehabilitation where patients can be trained to learn spatio-temporal patterns of healthy brain activity.

  11. Robotic guidance induces long-lasting changes in the movement pattern of a novel sport-specific motor task.

    PubMed

    Kümmel, Jakob; Kramer, Andreas; Gruber, Markus

    2014-12-01

    Facilitating the learning or relearning of motor tasks is one of the main goals of coaches, teachers and therapists. One promising way to achieve this goal is guiding the learner through the correct movement trajectory with the help of a robotic device. The aim of this study was to investigate if haptic guidance can induce long-lasting changes in the movement pattern of a complex sport-specific motor task. For this purpose, 31 subjects were assigned to one of three groups: EA (early angle, n=10), LA (late angle, n=11) and CON (control, n=10). EA and LA successfully completed five training sessions, which consisted of 50 robot-guided golf swings and 10 free swings each, whereas CON had no training. The EA group was guided through the movement with the wrist being bent early during backswing, whereas in the LA group it was bent late. The participants of EA and LA were not told about this difference in the movement patterns. To assess if the robot-guided training was successful in shaping the movement pattern, the timing of the wrist bending during the backswing in free swings was measured before (PRE), one day after (POST), and 7 days after (FUP) the five training sessions. The ANOVA (time×group×angle) showed that during POST and FUP, the participants of the EA group bent their wrist significantly earlier during the backswing than the other groups. Post-hoc analyses revealed that this interaction effect was mainly due to the differences in the wrist angle progression during the first 5° of the backswing. The robot-guided training was successful in shaping the movement pattern, and these changes persisted even after 7 days without further practice. This might have implications for the learning of complex motor tasks in general, as haptic guidance might quickly provide the beginner with an internal model of the correct movement pattern without having to direct the learner's attention towards the key points of the correct movement pattern. PMID:25238621

  12. Masticatory motor pattern in the koala (Phascolarctos cinereus): a comparison of jaw movements in marsupial and placental herbivores.

    PubMed

    Crompton, Alfred Walter; Owerkowicz, Tomasz; Skinner, Jayne

    2010-11-01

    Do closely related marsupial herbivores (Diprotodontia) conserve a common masticatory motor pattern or are motor patterns linked to the structure and function of the masticatory apparatus? We recorded the sequence and duration of activity of the individual jaw closing muscles during rhythmic chewing in koalas and then compared their motor pattern with that of their closest extant relatives, wombats, and their more distant marsupial relatives, macropodoids. These three lineages prove to have fundamentally different motor patterns and jaw movements during mastication. Each motor pattern represents independent modifications of an earlier motor pattern that was probably present in an ancestral diprotodontian. We show that koalas evolved a motor program that is in many aspects similar to that of placental herbivores with a fused mandibular symphysis (artiodactyls, perissodactyls, and higher primates) and almost identical to one artiodactyl, viz. alpacas. Anatomically, koalas are convergent on placental herbivores because they lost the inflected mandibular angle and large external part of the medial pterygoid muscle characteristic of other marsupials. We support the view that many different motor programs evolved for the control of transverse jaw movements, but identical motor programs for the control of transverse jaw movements can evolve independently in distantly related taxa. PMID:20683866

  13. Masticatory motor pattern in the koala (Phascolarctos cinereus): a comparison of jaw movements in marsupial and placental herbivores.

    PubMed

    Crompton, Alfred Walter; Owerkowicz, Tomasz; Skinner, Jayne

    2010-11-01

    Do closely related marsupial herbivores (Diprotodontia) conserve a common masticatory motor pattern or are motor patterns linked to the structure and function of the masticatory apparatus? We recorded the sequence and duration of activity of the individual jaw closing muscles during rhythmic chewing in koalas and then compared their motor pattern with that of their closest extant relatives, wombats, and their more distant marsupial relatives, macropodoids. These three lineages prove to have fundamentally different motor patterns and jaw movements during mastication. Each motor pattern represents independent modifications of an earlier motor pattern that was probably present in an ancestral diprotodontian. We show that koalas evolved a motor program that is in many aspects similar to that of placental herbivores with a fused mandibular symphysis (artiodactyls, perissodactyls, and higher primates) and almost identical to one artiodactyl, viz. alpacas. Anatomically, koalas are convergent on placental herbivores because they lost the inflected mandibular angle and large external part of the medial pterygoid muscle characteristic of other marsupials. We support the view that many different motor programs evolved for the control of transverse jaw movements, but identical motor programs for the control of transverse jaw movements can evolve independently in distantly related taxa.

  14. Bird-Borne Video-Cameras Show That Seabird Movement Patterns Relate to Previously Unrevealed Proximate Environment, Not Prey

    PubMed Central

    Tremblay, Yann; Thiebault, Andréa; Mullers, Ralf; Pistorius, Pierre

    2014-01-01

    The study of ecological and behavioral processes has been revolutionized in the last two decades with the rapid development of biologging-science. Recently, using image-capturing devices, some pilot studies demonstrated the potential of understanding marine vertebrate movement patterns in relation to their proximate, as opposed to remote sensed environmental contexts. Here, using miniaturized video cameras and GPS tracking recorders simultaneously, we show for the first time that information on the immediate visual surroundings of a foraging seabird, the Cape gannet, is fundamental in understanding the origins of its movement patterns. We found that movement patterns were related to specific stimuli which were mostly other predators such as gannets, dolphins or fishing boats. Contrary to a widely accepted idea, our data suggest that foraging seabirds are not directly looking for prey. Instead, they search for indicators of the presence of prey, the latter being targeted at the very last moment and at a very small scale. We demonstrate that movement patterns of foraging seabirds can be heavily driven by processes unobservable with conventional methodology. Except perhaps for large scale processes, local-enhancement seems to be the only ruling mechanism; this has profounds implications for ecosystem-based management of marine areas. PMID:24523892

  15. Terrestrial movement patterns of western pond turtles (Actinemys marmorata) in central California

    USGS Publications Warehouse

    Pilliod, David S.; Welty, Justin L.; Stafford, Robert

    2013-01-01

    We used radio telemetry to track the terrestrial movements and seasonal habitat use patterns of Western Pond Turtles (Actinemys marmorata) near two ponds in the Carrizo Plain Ecological Reserve, California, USA. We captured 93 turtles in September 2005 and, of these, we tagged three males and six females(weighing > 300 g) with external transmitters. Tagged turtles traveled from 255–1,096 m over the 448-day study, and we found none further than 343 m from ponds. All turtles moved away from the ponds as water levels receded in the fall, resulting in periods of terrestrial overwintering ranging from 10–30 weeks (74–202 d). We found no evidence for group migrations as turtles departed ponds over 2–8 week periods, moved in different directions from their ponds, and used different habitats. Turtles overwintered mainly in oak and chaparral vegetation communities, which constituted most of the local vegetation. We found overwintering turtles in a variety of microhabitats, but all turtles were on the surface with their carapace just visible amongst the duff layer. Turtles returned to ponds over several weeks, sometimes months after they refilled with winter rains. In the winter of 2006–2007, no turtles returned to terrestrial overwintering sites used the previous year. Most of the turtles we tracked spent over half of each year on land, demonstrating the importance of terrestrial habitats around these seasonal ponds. This pattern is similar to pond turtles living in streams (overwinter on land), as compared to permanent ponds (turtles often remain in water).

  16. Emotion modulates eye movement patterns and subsequent memory for the gist and details of movie scenes.

    PubMed

    Subramanian, Ramanathan; Shankar, Divya; Sebe, Nicu; Melcher, David

    2014-01-01

    A basic question in vision research regards where people look in complex scenes and how this influences their performance in various tasks. Previous studies with static images have demonstrated a close link between where people look and what they remember. Here, we examined the pattern of eye movements when participants watched neutral and emotional clips from Hollywood-style movies. Participants answered multiple-choice memory questions concerning visual and auditory scene details immediately upon viewing 1-min-long neutral or emotional movie clips. Fixations were more narrowly focused for emotional clips, and immediate memory for object details was worse compared to matched neutral scenes, implying preferential attention to emotional events. Although we found the expected correlation between where people looked and what they remembered for neutral clips, this relationship broke down for emotional clips. When participants were subsequently presented with key frames (static images) extracted from the movie clips such that presentation duration of the target objects (TOs) corresponding to the multiple-choice questions was matched and the earlier questions were repeated, more fixations were observed on the TOs, and memory performance also improved significantly, confirming that emotion modulates the relationship between gaze position and memory performance. Finally, in a long-term memory test, old/new recognition performance was significantly better for emotional scenes as compared to neutral scenes. Overall, these results are consistent with the hypothesis that emotional content draws eye fixations and strengthens memory for the scene gist while weakening encoding of peripheral scene details.

  17. Adaptation of lower limb movement patterns when maintaining performance in the presence of muscle fatigue.

    PubMed

    Mudie, Kurt L; Gupta, Amitabh; Green, Simon; Clothier, Peter J

    2016-08-01

    Adaptations in lower limb movement patterns were examined when performance was maintained during a fatiguing repetitive loading task. Forty recreationally active male and female participants performed single-leg hopping to volitional exhaustion at 2.2Hz to a submaximal height. Spatio-temporal characteristics, mechanical characteristics and variability of the knee-ankle and hip-knee joint couplings were determined at 20% increments during the duration of the hopping task. Variability of the knee-ankle and hip-knee couplings in the flexion/extension axis significantly increased during the loading and propulsion phases during the hopping task (p<0.05). Performance (vertical stiffness, hopping frequency and height) did not change significantly during the task (p>0.05), however foot contact time increased progressively during this task (p<0.05) and maximum hop height significantly decreased after the task (p<0.05). The observed increase in variability between adjoining lower limb segments demonstrated the ability of the neuromotor system to adapt and maintain performance even with the onset of fatigue. This finding highlights that during the performance of a rapid and repetitive loading activity, performance can be preserved when there is variability in the neuromotor system.

  18. Movement patterns of wintering lesser scaup in Grand Calumet River - Indiana Harbor Canal, Indiana

    USGS Publications Warehouse

    Custer, Christine M.; Custer, T.W.; Sparks, D.W.; Hines, Randy K.; Kochanny, C.O.

    1996-01-01

    Lesser scaup (Aythya affinis) winter in the Grand Calumet River-Indiana Harbor Canal (GCR-IHC) drainage into southern Lake Michigan, a polluted oasis in the highly urban and industrial corridor of northern Illinois and Indiana. The GCR-IHC is an important wintering area for lesser scaup in northwestern Indiana, especially after Lake Michigan freezes, because of the lack of other wildlife habitat in the area. We investigated the feeding and movement patterns of these wintering lesser scaup to better understand the ecological significance of this area to wintering waterfowl and to interpret contaminant levels in these lesser scaup. We implanted radio transmitters in 20 individuals in January 1994 and tracked them until early March 1994. Four lesser scaup disappeared and four died within the first 2 weeks after implantation; 12 lesser scaup remained in the GCR-IHC for the next 6-7 weeks. Individual radio-marked scaup (n = 12) were located in the GCR-IHC on an average of 62.2% (extreme values = 25-87%) of the searches. No radio-marked lesser scaup were located outside the GCR-IHC. Lesser scaup were feeding during 23% of the radio fixes.

  19. Movement and spawning migration patterns suggest small marine reserves can offer adequate protection for exploited emperorfishes

    NASA Astrophysics Data System (ADS)

    Taylor, B. M.; Mills, J. S.

    2013-12-01

    A critical feature of effective marine reserves is to be large enough to encompass home ranges of target species, thereby allowing a significant portion of the population to persist without the threat of exploitation. In this study, patterns of movement and home range for Lethrinus harak and Lethrinus obsoletus were quantified using an array of 33 acoustic receivers that covered approximately three quarters of Piti Marine Reserve in the Pacific island of Guam. This array was designed to ensure extensive overlap of receiver ranges throughout the study area. Eighteen individuals (12 L. harak and 6 L. obsoletus) were surgically implanted with ultrasonic transmitters and passively tracked for 4 months. Both species displayed high site fidelity and had relatively small home ranges. The home ranges of L. harak expanded with increasing body size. Feeding of fish by humans, which was common but restricted to a small area within the study site, had little effect on the distribution of the resident populations. L. harak made nightly spawning migrations within the reserve between full moon and last quarter moon of each lunar cycle, coinciding with a strong ebbing tide. Results indicate that even small reserves can include many individual home ranges of these emperorfishes and can protect spawning sites for L. harak. These species are heavily targeted in Guam, and there are major demographic differences between fished and protected sites. This study shows the potential for protected areas to sustain reproductive viability in exploited populations.

  20. Pattern of solute movement from snow into an upper Michigan stream

    USGS Publications Warehouse

    Stottlemyer, R.; Toczydlowski, D.

    1990-01-01

    Precipitation, snowpack, snowmelt, and streamwater samples were collected in a small gauged watershed draining into Lake Superior during winter 1987–88 to assess the importance of snowmelt pattern and meltwater pathways in the occurrence of solute pulses in streamwater. The snowpack along the south shore of Lake Superior can contain 50% of annual precipitation inputs and 38% of annual ionic inputs including moderate levels of strong acids. Throughout winter, thawed surface soils and small but steady snowpack moisture release promoted movement of snowpack solutes to surface mineral soils. Preferential elution of K+, NH4+, and H+ from the snowpack occurred with the initial thaw. Most ions exhibited pulses in snowmelt. Transport of snowpack solutes to the stream during snowmelt was through near-surface soil macropores and overland flow. For those ions with concentrations higher in the snowpack than in the premelt streamwater, K+, NH4+, and H+, the earliest snowmelt pulses had the greatest influence on streamwater chemistry. Unlike other portions of the region with resistant bedrock, the widespread presence of alkaline glacial till provides excess stream acid neutralization capacity (ANC) to buffer acidic inputs. Peak winter streamwater ANC reduction was caused principally by spring melt dilution of base cations and associated alkalinity, constant high SO42- levels, and an increase in NO3-. The maximum reduction in stream ANC was concurrent with overland flow. Relative to its snowmelt concentration, NO3- was highest in streamwater with some stream input likely the result of nitrification and N mineralization.

  1. Adaptation of lower limb movement patterns when maintaining performance in the presence of muscle fatigue.

    PubMed

    Mudie, Kurt L; Gupta, Amitabh; Green, Simon; Clothier, Peter J

    2016-08-01

    Adaptations in lower limb movement patterns were examined when performance was maintained during a fatiguing repetitive loading task. Forty recreationally active male and female participants performed single-leg hopping to volitional exhaustion at 2.2Hz to a submaximal height. Spatio-temporal characteristics, mechanical characteristics and variability of the knee-ankle and hip-knee joint couplings were determined at 20% increments during the duration of the hopping task. Variability of the knee-ankle and hip-knee couplings in the flexion/extension axis significantly increased during the loading and propulsion phases during the hopping task (p<0.05). Performance (vertical stiffness, hopping frequency and height) did not change significantly during the task (p>0.05), however foot contact time increased progressively during this task (p<0.05) and maximum hop height significantly decreased after the task (p<0.05). The observed increase in variability between adjoining lower limb segments demonstrated the ability of the neuromotor system to adapt and maintain performance even with the onset of fatigue. This finding highlights that during the performance of a rapid and repetitive loading activity, performance can be preserved when there is variability in the neuromotor system. PMID:27101562

  2. Movement patterns and physical strain during a novel, simulated cricket batting innings (BATEX).

    PubMed

    Houghton, Laurence; Dawson, Brian; Rubenson, Jonas; Tobin, Martin

    2011-05-01

    A simulated cricket batting innings was developed to replicate the physical demands of scoring a century during One-Day International cricket. The simulated innings requires running-between-the-wickets across six 5-over stages, each of 21 min duration. To validate whether the simulated batting innings is reflective of One-Day International batting, movement patterns were collected using a global positioning system (GPS) and compared with previous research. In addition, indicators of physical strain were recorded (heart rate, jump heights, sweat loss, tympanic temperature). Nine club cricketers (mean ± s: age 20 ± 3 years; body mass 79.5 ± 7.9 kg) performed the simulated innings outdoors. There was a moderate trend for distance covered in the simulated innings to be less than that during One-Day batting (2171 ± 157 vs. 2476 ± 631 m · h⁻¹; effect size = 0.78). This difference was largely explained by a strong trend for less distance covered walking in the simulated innings than in One-Day batting (1359 ± 157 vs. 1604 ± 438 m · h⁻¹; effect size = 1.61). However, there was a marked trend for distance covered both striding and sprinting to be greater in the simulated innings than in One-Day batting (effect size > 1.2). Practically, the simulated batting innings may be used for match-realistic physical training and as a research protocol to assess the demands of prolonged, high-intensity cricket batting.

  3. Do adult readers know how they read? Evidence from eye movement patterns and verbal reports.

    PubMed

    Hyönä, Jukka; Nurminen, Anna-Mari

    2006-02-01

    The present study was carried out to investigate individual differences in reading styles among competent adult readers and to examine whether readers are aware of their reading style. Individual reading strategies were studied by having the participants read a long expository text while their eye fixation patterns were registered. A cluster analysis was performed on the eye movement data to distinguish between different reading styles. The analysis revealed three types of readers that were coined, following Hyönä, Lorch, and Kaakinen (2002), fast linear readers, slow linear readers, and topic structure processors. Readers' procedural awareness of their reading behaviour was assessed by a questionnaire. The verbal reports obtained by the questionnaire were then correlated with the corresponding eye behaviour to investigate the extent to which the readers behave the way they report doing. The correlations showed that adult readers are well aware of their general reading speed and reasonably aware of their lookback and rereading behaviour. The amount of time spent looking back in text also correlated positively with the relative success in recalling the main points expressed in the text. It is concluded that systematic and extensive looking back in text is indicative of strategic behaviour. PMID:16464286

  4. The Relation between Reading Skills and Eye Movement Patterns in Adolescent Readers: Evidence from a Regular Orthography.

    PubMed

    Krieber, Magdalena; Bartl-Pokorny, Katrin D; Pokorny, Florian B; Einspieler, Christa; Langmann, Andrea; Körner, Christof; Falck-Ytter, Terje; Marschik, Peter B

    2016-01-01

    Over the past decades, the relation between reading skills and eye movement behavior has been well documented in English-speaking cohorts. As English and German differ substantially with regard to orthographic complexity (i.e. grapheme-phoneme correspondence), we aimed to delineate specific characteristics of how reading speed and reading comprehension interact with eye movements in typically developing German-speaking (Austrian) adolescents. Eye movements of 22 participants (14 females; mean age = 13;6 years;months) were tracked while they were performing three tasks, namely silently reading words, texts, and pseudowords. Their reading skills were determined by means of a standardized German reading speed and reading comprehension assessment (Lesegeschwindigkeits- und -verständnistest für Klassen 6-12). We found that (a) reading skills were associated with various eye movement parameters in each of the three reading tasks; (b) better reading skills were associated with an increased efficiency of eye movements, but were primarily linked to spatial reading parameters, such as the number of fixations per word, the total number of saccades and saccadic amplitudes; (c) reading speed was a more reliable predictor for eye movement parameters than reading comprehension; (d) eye movements were highly correlated across reading tasks, which indicates consistent reading performances. Contrary to findings in English-speaking cohorts, the reading skills neither consistently correlated with temporal eye movement parameters nor with the number or percentage of regressions made while performing any of the three reading tasks. These results indicate that, although reading skills are associated with eye movement patterns irrespective of language, the temporal and spatial characteristics of this association may vary with orthographic consistency.

  5. The Relation between Reading Skills and Eye Movement Patterns in Adolescent Readers: Evidence from a Regular Orthography.

    PubMed

    Krieber, Magdalena; Bartl-Pokorny, Katrin D; Pokorny, Florian B; Einspieler, Christa; Langmann, Andrea; Körner, Christof; Falck-Ytter, Terje; Marschik, Peter B

    2016-01-01

    Over the past decades, the relation between reading skills and eye movement behavior has been well documented in English-speaking cohorts. As English and German differ substantially with regard to orthographic complexity (i.e. grapheme-phoneme correspondence), we aimed to delineate specific characteristics of how reading speed and reading comprehension interact with eye movements in typically developing German-speaking (Austrian) adolescents. Eye movements of 22 participants (14 females; mean age = 13;6 years;months) were tracked while they were performing three tasks, namely silently reading words, texts, and pseudowords. Their reading skills were determined by means of a standardized German reading speed and reading comprehension assessment (Lesegeschwindigkeits- und -verständnistest für Klassen 6-12). We found that (a) reading skills were associated with various eye movement parameters in each of the three reading tasks; (b) better reading skills were associated with an increased efficiency of eye movements, but were primarily linked to spatial reading parameters, such as the number of fixations per word, the total number of saccades and saccadic amplitudes; (c) reading speed was a more reliable predictor for eye movement parameters than reading comprehension; (d) eye movements were highly correlated across reading tasks, which indicates consistent reading performances. Contrary to findings in English-speaking cohorts, the reading skills neither consistently correlated with temporal eye movement parameters nor with the number or percentage of regressions made while performing any of the three reading tasks. These results indicate that, although reading skills are associated with eye movement patterns irrespective of language, the temporal and spatial characteristics of this association may vary with orthographic consistency. PMID:26727255

  6. The Relation between Reading Skills and Eye Movement Patterns in Adolescent Readers: Evidence from a Regular Orthography

    PubMed Central

    Krieber, Magdalena; Bartl-Pokorny, Katrin D.; Pokorny, Florian B.; Einspieler, Christa; Langmann, Andrea; Körner, Christof; Falck-Ytter, Terje; Marschik, Peter B.

    2016-01-01

    Over the past decades, the relation between reading skills and eye movement behavior has been well documented in English-speaking cohorts. As English and German differ substantially with regard to orthographic complexity (i.e. grapheme-phoneme correspondence), we aimed to delineate specific characteristics of how reading speed and reading comprehension interact with eye movements in typically developing German-speaking (Austrian) adolescents. Eye movements of 22 participants (14 females; mean age = 13;6 years;months) were tracked while they were performing three tasks, namely silently reading words, texts, and pseudowords. Their reading skills were determined by means of a standardized German reading speed and reading comprehension assessment (Lesegeschwindigkeits- und -verständnistest für Klassen 6−12). We found that (a) reading skills were associated with various eye movement parameters in each of the three reading tasks; (b) better reading skills were associated with an increased efficiency of eye movements, but were primarily linked to spatial reading parameters, such as the number of fixations per word, the total number of saccades and saccadic amplitudes; (c) reading speed was a more reliable predictor for eye movement parameters than reading comprehension; (d) eye movements were highly correlated across reading tasks, which indicates consistent reading performances. Contrary to findings in English-speaking cohorts, the reading skills neither consistently correlated with temporal eye movement parameters nor with the number or percentage of regressions made while performing any of the three reading tasks. These results indicate that, although reading skills are associated with eye movement patterns irrespective of language, the temporal and spatial characteristics of this association may vary with orthographic consistency. PMID:26727255

  7. Fatigue-Induced Changes in Movement Pattern and Muscle Activity During Ballet Releve on Demi-Pointe.

    PubMed

    Lin, Cheng-Feng; Lee, Wan-Chin; Chen, Yi-An; Hsue, Bih-Jen

    2016-08-01

    Fatigue in ballet dancers may lead to injury, particularly in the lower extremities. However, few studies have investigated the effects of fatigue on ballet dancers' performance and movement patterns. Thus, the current study examines the effect of fatigue on the balance, movement pattern, and muscle activities of the lower extremities in ballet dancers. Twenty healthy, female ballet dancers performed releve on demi-pointe before and after fatigue. The trajectory of the whole body movement and the muscle activities of the major lower extremity muscles were recorded continuously during task performance. The results show that fatigue increases the medial-lateral center of mass (COM) displacement and hip and trunk motion, but decreases the COM velocity and ankle motion. Moreover, fatigue reduces the activities of the hamstrings and tibialis anterior, but increases that of the soleus. Finally, greater proximal hip and trunk motions are applied to compensate for the effects of fatigue, leading to a greater COM movement. Overall, the present findings show that fatigue results in impaired movement control and may therefore increase the risk of dance injury. PMID:26955753

  8. Fatigue-Induced Changes in Movement Pattern and Muscle Activity During Ballet Releve on Demi-Pointe.

    PubMed

    Lin, Cheng-Feng; Lee, Wan-Chin; Chen, Yi-An; Hsue, Bih-Jen

    2016-08-01

    Fatigue in ballet dancers may lead to injury, particularly in the lower extremities. However, few studies have investigated the effects of fatigue on ballet dancers' performance and movement patterns. Thus, the current study examines the effect of fatigue on the balance, movement pattern, and muscle activities of the lower extremities in ballet dancers. Twenty healthy, female ballet dancers performed releve on demi-pointe before and after fatigue. The trajectory of the whole body movement and the muscle activities of the major lower extremity muscles were recorded continuously during task performance. The results show that fatigue increases the medial-lateral center of mass (COM) displacement and hip and trunk motion, but decreases the COM velocity and ankle motion. Moreover, fatigue reduces the activities of the hamstrings and tibialis anterior, but increases that of the soleus. Finally, greater proximal hip and trunk motions are applied to compensate for the effects of fatigue, leading to a greater COM movement. Overall, the present findings show that fatigue results in impaired movement control and may therefore increase the risk of dance injury. PMID:27622498

  9. Identification of distinct movement patterns in Pacific leatherback turtle populations influenced by ocean conditions.

    PubMed

    Bailey, Helen; Benson, Scott R; Shillinger, George L; Bograd, Steven J; Dutton, Peter H; Eckert, Scott A; Morreale, Stephen J; Paladino, Frank V; Eguchi, Tomoharu; Foley, David G; Block, Barbara A; Piedra, Rotney; Hitipeuw, Creusa; Tapilatu, Ricardo F; Spotila, James R

    2012-04-01

    Interactions with fisheries are believed to be a major cause of mortality for adult leatherback turtles (Dermochelys coriacea), which is of particular concern in the Pacific Ocean, where they have been rapidly declining. In order to identify where these interactions are occurring and how they may be reduced, it is essential first to understand the movements and behavior of leatherback turtles. There are two regional nesting populations in the East Pacific (EP) and West Pacific (WP), comprising multiple nesting sites. We synthesized tracking data from the two populations and compared their movement patterns. A switching state-space model was applied to 135 Argos satellite tracks to account for observation error, and to distinguish between migratory and area-restricted search behaviors. The tracking data, from the largest leatherback data set ever assembled, indicated that there was a high degree of spatial segregation between EP and WP leatherbacks. Area-restricted search behavior mainly occurred in the southeast Pacific for the EP leatherbacks, whereas the WP leatherbacks had several different search areas in the California Current, central North Pacific, South China Sea, off eastern Indonesia, and off southeastern Australia. We also extracted remotely sensed oceanographic data and applied a generalized linear mixed model to determine if leatherbacks exhibited different behavior in relation to environmental variables. For the WP population, the probability of area-restricted search behavior was positively correlated with chlorophyll-a concentration. This response was less strong in the EP population, but these turtles had a higher probability of search behavior where there was greater Ekman upwelling, which may increase the transport of nutrients and consequently prey availability. These divergent responses to oceanographic conditions have implications for leatherback vulnerability to fisheries interactions and to the effects of climate change. The occurrence of

  10. Identification of distinct movement patterns in Pacific leatherback turtle populations influenced by ocean conditions.

    PubMed

    Bailey, Helen; Benson, Scott R; Shillinger, George L; Bograd, Steven J; Dutton, Peter H; Eckert, Scott A; Morreale, Stephen J; Paladino, Frank V; Eguchi, Tomoharu; Foley, David G; Block, Barbara A; Piedra, Rotney; Hitipeuw, Creusa; Tapilatu, Ricardo F; Spotila, James R

    2012-04-01

    Interactions with fisheries are believed to be a major cause of mortality for adult leatherback turtles (Dermochelys coriacea), which is of particular concern in the Pacific Ocean, where they have been rapidly declining. In order to identify where these interactions are occurring and how they may be reduced, it is essential first to understand the movements and behavior of leatherback turtles. There are two regional nesting populations in the East Pacific (EP) and West Pacific (WP), comprising multiple nesting sites. We synthesized tracking data from the two populations and compared their movement patterns. A switching state-space model was applied to 135 Argos satellite tracks to account for observation error, and to distinguish between migratory and area-restricted search behaviors. The tracking data, from the largest leatherback data set ever assembled, indicated that there was a high degree of spatial segregation between EP and WP leatherbacks. Area-restricted search behavior mainly occurred in the southeast Pacific for the EP leatherbacks, whereas the WP leatherbacks had several different search areas in the California Current, central North Pacific, South China Sea, off eastern Indonesia, and off southeastern Australia. We also extracted remotely sensed oceanographic data and applied a generalized linear mixed model to determine if leatherbacks exhibited different behavior in relation to environmental variables. For the WP population, the probability of area-restricted search behavior was positively correlated with chlorophyll-a concentration. This response was less strong in the EP population, but these turtles had a higher probability of search behavior where there was greater Ekman upwelling, which may increase the transport of nutrients and consequently prey availability. These divergent responses to oceanographic conditions have implications for leatherback vulnerability to fisheries interactions and to the effects of climate change. The occurrence of

  11. An investigation of the movement patterns and biosecurity practices on Thoroughbred and Standardbred stud farms in New Zealand.

    PubMed

    Rosanowski, S M; Cogger, N; Rogers, C W

    2013-02-01

    Utilising a face-to-face interview of stud managers, a survey was conducted to investigate the movement patterns around, and biosecurity practices on, Thoroughbred and Standardbred stud farms. Eligible stud farms (n=60) were identified from the 2009 Thoroughbred stallion register and 2009 Standardbred stallion register, and stud managers were asked to participate in the interview. In total, 27 stud managers agreed to participate in the study, and participating stud farms included 38% of Thoroughbred and 60% of Standardbred mares bred in 2009. All stud managers reported the movement of horses to and from their stud farm. The median number of movement events per year was 127 (interquartile range 83-300). The frequency of movement events from a stud farm was not associated with the breed of horse managed on the stud farm, however Thoroughbred horses travelled further than Standardbred horses during these movement events (P<0.001). The movement patterns of horses around stud farms showed a strong seasonality associated with the commercial breeding season of each breed. While 26 (96%) of stud managers reported having procedures in place for checking newly arriving horses, only 6 (22%) stud managers reported isolating horses on arrival as a standard protocol. The main reason for isolating horses on properties, where isolation was not a standard procedure, was in response to strangles outbreaks on other stud farms (n=10). Only 2 (7%) stud managers reported implementing visitor protocols, and these protocols only applied to visiting veterinarians, but not to farriers. These findings have important implications for the control of both endemic and exotic infectious disease outbreaks within the New Zealand breeding population as the high frequency of movement around stud farms, the high number of visitors to stud farms and the lack of effective biosecurity practices or visitor protocols will be critical factors in the spread of equine influenza during an outbreak.

  12. RGS4 is involved in the generation of abnormal involuntary movements in the unilateral 6-OHDA-lesioned rat model of Parkinson's disease.

    PubMed

    Ko, Wai Kin D; Martin-Negrier, Marie-Laure; Bezard, Erwan; Crossman, Alan R; Ravenscroft, Paula

    2014-10-01

    Regulators of G-protein signalling (RGS) proteins are implicated in striatal G-protein coupled receptor (GPCR) sensitisation in the pathophysiology of l-DOPA-induced abnormal involuntary movements (AIMs), also known as dyskinesia (LID), in Parkinson's disease (PD). In this study, we investigated RGS protein subtype 4 in the expression of AIMs in the unilateral 6-hydroxydopamine (6-OHDA)-lesioned rat model of LID. The effects of RGS4 antisense brain infusion on the behavioural and molecular correlates of l-DOPA priming in 6-OHDA-lesioned rats were assessed. In situ hybridisation revealed that repeated l-DOPA/benserazide treatment caused an elevation of RGS4 mRNA levels in the striatum, predominantly in the lateral regions. The increased expression of RGS4 mRNA in the rostral striatum was found to positively correlate with the behavioural (AIM scores) and molecular (pre-proenkephalin B, PPE-B expression) markers of LID. We found that suppressing the elevation of RGS4 mRNA in the striatum by continuous infusion of RGS4 antisense oligonucleotides, via implanted osmotic mini-pumps, during l-DOPA priming, reduced the induction of AIMs. Moreover, ex vivo analyses of the rostral dorsolateral striatum showed that RGS4 antisense infusion attenuated l-DOPA-induced elevations of PPE-B mRNA and dopamine-stimulated [(35)S]GTPγS binding, a marker used for measuring dopamine receptor super-sensitivity. Taken together, these data suggest that (i) RGS4 proteins play an important pathophysiological role in the development and expression of LID and (ii) suppressing the elevation of RGS4 mRNA levels in l-DOPA priming attenuates the associated pathological changes in LID, dampening its physiological expression. Thus, modulating RGS4 proteins could prove beneficial in the treatment of dyskinesia in PD.

  13. Applying Eye Movement Miscue Analysis to the Reading Patterns of Children with Language Impairment

    ERIC Educational Resources Information Center

    Nelson, Ryan L.; Damico, Jack S.; Smith, Sunny K.

    2008-01-01

    This paper presents a research report on an investigation into the reading eye movements of a bilingual 10-year, 10-month old girl with language impairment secondary to Downs Syndrome. Eye movement miscue analysis (Paulson, 2000) was employed to evaluate the visual sampling and oral productions of this child as she read from complete texts…

  14. Adult Movement Pattern and Habitat Preferences of the Maghribian Endemic Gomphus lucasii (Odonata: Gomphidae)

    PubMed Central

    Zebsa, Rabah; Khelifa, Rassim; Kahalerras, Amin

    2015-01-01

    The Algerian Cubtail (Gomphus lucasii Selys) (Odonata: Gomphidae) is a river-dwelling dragonfly and one of the least known gomphid in the Palearctic. A survey of the movement patterns and habitat requirements of adults was conducted in the largest currently known population, located in the Seybouse River (Northeast Algeria). Daily mark-release-resighting surveys along a 2.5 km stretch of the watercourse and within plots in terrestrial habitats were carried out; a total of 1,316 individuals were marked. The resighting rate along the watercourse was 8.13% and did not significantly vary with sex and age. Adult spatial distribution differed according to sex and age. Mature females were significantly further from the water than males. Mature males were observed not only along the watercourse but also far from the water, up to 450 m where reproductive pairs in copula were recorded. Preferred maturation and foraging sites were open grasslands and dense wheat fields. Philopatry to reproductive sites had a mean of 1.11%, while philopatry to emergence site was lower (0.4%) and noted only in males. The mean distance of natal dispersal (from emergence to reproductive areas) was 596.5 ± 4.94 m. The mean dispersal distance from one reproductive site to another was 180.97 ± 238.54 m. Both mature males and females preferred fast flowing water, but females were observed to oviposit in relatively small watercourses.

  15. Elite football on artificial turf versus natural grass: movement patterns, technical standards, and player impressions.

    PubMed

    Andersson, Helena; Ekblom, Björn; Krustrup, Peter

    2008-01-15

    The aim of the present study was to examine the movement patterns, ball skills, and the impressions of Swedish elite football players during competitive games on artificial turf and natural grass. Time - motion analyses (36 observations) and technical analyses (16 team observations) were performed and 72 male and 21 female players completed a questionnaire. No differences were observed between artificial turf and natural grass in terms of total distance covered (mean 10.19 km, s = 0.19 vs. 10.33 km, s = 0.23), high-intensity running (1.86 km, s = 0.10 vs. 1.87 km, s = 0.14), number of sprints (21, s = 1 vs. 22, s = 2), standing tackles (10, s = 1 vs. 11, s = 1) or headers per game (8, s = 1 vs. 8, s = 1), whereas there were fewer sliding tackles (P < 0.05) on artificial turf than natural grass (2.1, s = 0.5 vs. 4.3, s = 0.6). There were more short passes (218, s = 14 vs. 167, s = 12) and midfield-to-midfield passes (148, s = 11 vs. 107, s = 8) (both P < 0.05) on artificial turf than natural grass. On a scale of 0-10, where 0 = "better than", 5 = "equal to", and 10 = "worse than", the male players reported a negative overall impression (8.3, s = 0.2), poorer ball control (7.3, s = 0.3), and greater physical effort (7.2, s = 0.2) on artificial turf than natural grass. In conclusion, the running activities and technical standard were similar during games on artificial turf and natural grass. However, fewer sliding tackles and more short passes were performed during games on artificial turf. The observed change in playing style could partly explain the male players' negative impression of artificial turf.

  16. A comparison of the real-time controllability of pattern recognition to conventional myoelectric control for discrete and simultaneous movements.

    PubMed

    Young, Aaron J; Smith, Lauren H; Rouse, Elliott J; Hargrove, Levi J

    2014-01-10

    Myoelectric control has been used for decades to control powered upper limb prostheses. Conventional, amplitude-based control has been employed to control a single prosthesis degree of freedom (DOF) such as closing and opening of the hand. Within the last decade, new and advanced arm and hand prostheses have been constructed that are capable of actuating numerous DOFs. Pattern recognition control has been proposed to control a greater number of DOFs than conventional control, but has traditionally been limited to sequentially controlling DOFs one at a time. However, able-bodied individuals use multiple DOFs simultaneously, and it may be beneficial to provide amputees the ability to perform simultaneous movements. In this study, four amputees who had undergone targeted motor reinnervation (TMR) surgery with previous training using myoelectric prostheses were configured to use three control strategies: 1) conventional amplitude-based myoelectric control, 2) sequential (one-DOF) pattern recognition control, 3) simultaneous pattern recognition control. Simultaneous pattern recognition was enabled by having amputees train each simultaneous movement as a separate motion class. For tasks that required control over just one DOF, sequential pattern recognition based control performed the best with the lowest average completion times, completion rates and length error. For tasks that required control over 2 DOFs, the simultaneous pattern recognition controller performed the best with the lowest average completion times, completion rates and length error compared to the other control strategies. In the two strategies in which users could employ simultaneous movements (conventional and simultaneous pattern recognition), amputees chose to use simultaneous movements 78% of the time with simultaneous pattern recognition and 64% of the time with conventional control for tasks that required two DOF motions to reach the target. These results suggest that when amputees are given the

  17. Differences in Movement Pattern and Detectability between Males and Females Influence How Common Sampling Methods Estimate Sex Ratio

    PubMed Central

    Rodrigues, João Fabrício Mota; Coelho, Marco Túlio Pacheco

    2016-01-01

    Sampling the biodiversity is an essential step for conservation, and understanding the efficiency of sampling methods allows us to estimate the quality of our biodiversity data. Sex ratio is an important population characteristic, but until now, no study has evaluated how efficient are the sampling methods commonly used in biodiversity surveys in estimating the sex ratio of populations. We used a virtual ecologist approach to investigate whether active and passive capture methods are able to accurately sample a population’s sex ratio and whether differences in movement pattern and detectability between males and females produce biased estimates of sex-ratios when using these methods. Our simulation allowed the recognition of individuals, similar to mark-recapture studies. We found that differences in both movement patterns and detectability between males and females produce biased estimates of sex ratios. However, increasing the sampling effort or the number of sampling days improves the ability of passive or active capture methods to properly sample sex ratio. Thus, prior knowledge regarding movement patterns and detectability for species is important information to guide field studies aiming to understand sex ratio related patterns. PMID:27441554

  18. A mutual support mechanism through intercellular movement of CAPRICE and GLABRA3 can pattern the Arabidopsis root epidermis.

    PubMed

    Savage, Natasha Saint; Walker, Tom; Wieckowski, Yana; Schiefelbein, John; Dolan, Liam; Monk, Nicholas A M

    2008-09-23

    The patterning of the Arabidopsis root epidermis depends on a genetic regulatory network that operates both within and between cells. Genetic studies have identified a number of key components of this network, but a clear picture of the functional logic of the network is lacking. Here, we integrate existing genetic and biochemical data in a mathematical model that allows us to explore both the sufficiency of known network interactions and the extent to which additional assumptions about the model can account for wild-type and mutant data. Our model shows that an existing hypothesis concerning the autoregulation of WEREWOLF does not account fully for the expression patterns of components of the network. We confirm the lack of WEREWOLF autoregulation experimentally in transgenic plants. Rather, our modelling suggests that patterning depends on the movement of the CAPRICE and GLABRA3 transcriptional regulators between epidermal cells. Our combined modelling and experimental studies show that WEREWOLF autoregulation does not contribute to the initial patterning of epidermal cell fates in the Arabidopsis seedling root. In contrast to a patterning mechanism relying on local activation, we propose a mechanism based on lateral inhibition with feedback. The active intercellular movements of proteins that are central to our model underlie a mechanism for pattern formation in planar groups of cells that is centred on the mutual support of two cell fates rather than on local activation and lateral inhibition.

  19. Residential movement patterns of families of young children with chronic conditions in Ontario, Canada: a population-based cohort study

    PubMed Central

    2013-01-01

    Introduction Care giving for children with chronic diseases can lead to financial strain and compromised family well being. Little is known about whether these stresses lead to changes in residential movement patterns as they relate to income adequacy and proximity to care. Methods We compared the residential movement patterns and associated changes in neighbourhood income of children with mild to severe chronic diseases compared with those that are healthy. A cohort of infants born from 2002–2007 in Ontario, Canada was followed for 5 years and divided into those with single- or multiple- body system complex chronic conditions (CCCs); low birth weight (LBW); asthma/recurrent wheeze (A/RW) and the control group of otherwise healthy children. Results Of 598,716 children studied, 15,207 had a single CCC, 3,600 multiple CCCs, 33,206 LBW, 57,137 A/RW and 489,566 were healthy. Lowest income quintile children were most likely to move residence. Compared with healthy controls, chronic disease cohorts, apart from those with asthma, were more likely to be born in the lowest income quintile neighbourhood and to move. Among children who moved, all chronic disease cohorts were significantly more likely to move to a low income quintile neighborhood (adjusted odds ratios for all chronic disease cohorts of 1.1-1.2). There were no differences across cohorts in residential movement close to a children’s hospital. Conclusions Young children with chronic conditions, particularly those born in low income neighbourhoods, are more likely to move residence than other healthy young children. However, it does not seem that proximity to specialized care is driving this movement. Further research is required to determine if these movement patterns impact the ability of children with chronic conditions to secure health services. PMID:23962036

  20. A minimal limit-cycle model to profile movement patterns of individuals during agility drill performance: Effects of skill level.

    PubMed

    Mehdizadeh, Sina; Arshi, Ahmed Reza; Davids, Keith

    2015-06-01

    Identification of control strategies during agility performance is significant in understanding movement behavior. This study aimed at providing a fundamental mathematical model for describing the motion of participants during an agility drill and to determine whether skill level constrained model components. Motion patterns of two groups of skilled and unskilled participants (n=8 in each) during performance of a forward/backward agility drill modeled as limit-cycles. Participant movements were recorded by motion capture of a reflective marker attached to the sacrum of each individual. Graphical and regression analyses of movement kinematics in Hooke's plane, phase plane and velocity profile were performed to determine components of the models. Results showed that the models of both skilled and unskilled groups had terms from Duffing stiffness as well as Van der Pol damping oscillators. Data also indicated that the proposed models captured on average 97% of the variance for both skilled and unskilled groups. Findings from this study revealed the movement patterning associated with skilled and unskilled performance in a typical forward/backward agility drill which might be helpful for trainers and physiotherapists in enhancing agility. PMID:25828582

  1. Restoration of Central Programmed Movement Pattern by Temporal Electrical Stimulation-Assisted Training in Patients with Spinal Cerebellar Atrophy.

    PubMed

    Huang, Ying-Zu; Chang, Yao-Shun; Hsu, Miao-Ju; Wong, Alice M K; Chang, Ya-Ju

    2015-01-01

    Disrupted triphasic electromyography (EMG) patterns of agonist and antagonist muscle pairs during fast goal-directed movements have been found in patients with hypermetria. Since peripheral electrical stimulation (ES) and motor training may modulate motor cortical excitability through plasticity mechanisms, we aimed to investigate whether temporal ES-assisted movement training could influence premovement cortical excitability and alleviate hypermetria in patients with spinal cerebellar ataxia (SCA). The EMG of the agonist extensor carpi radialis muscle and antagonist flexor carpi radialis muscle, premovement motor evoked potentials (MEPs) of the flexor carpi radialis muscle, and the constant and variable errors of movements were assessed before and after 4 weeks of ES-assisted fast goal-directed wrist extension training in the training group and of general health education in the control group. After training, the premovement MEPs of the antagonist muscle were facilitated at 50 ms before the onset of movement. In addition, the EMG onset latency of the antagonist muscle shifted earlier and the constant error decreased significantly. In summary, temporal ES-assisted training alleviated hypermetria by restoring antagonist premovement and temporal triphasic EMG patterns in SCA patients. This technique may be applied to treat hypermetria in cerebellar disorders. (This trial is registered with NCT01983670.). PMID:26417459

  2. Assessment of Movement Patterns during Intubation between Novice and Experienced Providers Using Mobile Sensors: A Preliminary, Proof of Concept Study

    PubMed Central

    Carlson, Jestin N.; Das, Samarjit; Spring, Stephanie; Frisch, Adam; De la Torre, Fernando; Hodgins, Jessica

    2015-01-01

    Background. There are likely marked differences in endotracheal intubation (ETI) techniques between novice and experienced providers. We performed a proof of concept study to determine if portable motion technology could identify the motion components of ETI between novice and experienced providers. Methods. We recruited a sample of novice and experienced providers to perform ETIs on a cadaver. Their movements during ETI were recorded with inertial measurement units (IMUs) on the left wrist. The signals were assessed visually between novice and experienced providers to identify areas of differences at key steps during ETI. We then calculated spectral smoothness (SS), a quantitative measure inversely related to movement variability, for all ETI attempts. Results. We enrolled five novice and five experienced providers. When visually inspecting the data, we noted maximum variability when inserting the blade of the laryngoscope into the mouth and while visualizing the glottic opening. Novice providers also had greater overall variability in their movement patterns (SS novice 6.4 versus SS experienced 26.6). Conclusion. Portable IMUs can be used to detect differences in movement patterns between novice and experienced providers in cadavers. Future ETI educational efforts may utilize portable IMUs to help accelerate the learning curve of novice providers. PMID:26161417

  3. Restoration of Central Programmed Movement Pattern by Temporal Electrical Stimulation-Assisted Training in Patients with Spinal Cerebellar Atrophy.

    PubMed

    Huang, Ying-Zu; Chang, Yao-Shun; Hsu, Miao-Ju; Wong, Alice M K; Chang, Ya-Ju

    2015-01-01

    Disrupted triphasic electromyography (EMG) patterns of agonist and antagonist muscle pairs during fast goal-directed movements have been found in patients with hypermetria. Since peripheral electrical stimulation (ES) and motor training may modulate motor cortical excitability through plasticity mechanisms, we aimed to investigate whether temporal ES-assisted movement training could influence premovement cortical excitability and alleviate hypermetria in patients with spinal cerebellar ataxia (SCA). The EMG of the agonist extensor carpi radialis muscle and antagonist flexor carpi radialis muscle, premovement motor evoked potentials (MEPs) of the flexor carpi radialis muscle, and the constant and variable errors of movements were assessed before and after 4 weeks of ES-assisted fast goal-directed wrist extension training in the training group and of general health education in the control group. After training, the premovement MEPs of the antagonist muscle were facilitated at 50 ms before the onset of movement. In addition, the EMG onset latency of the antagonist muscle shifted earlier and the constant error decreased significantly. In summary, temporal ES-assisted training alleviated hypermetria by restoring antagonist premovement and temporal triphasic EMG patterns in SCA patients. This technique may be applied to treat hypermetria in cerebellar disorders. (This trial is registered with NCT01983670.).

  4. Patterns of white matter diffusivity abnormalities in Leber's hereditary optic neuropathy: a tract-based spatial statistics study.

    PubMed

    Milesi, Jacopo; Rocca, Maria A; Bianchi-Marzoli, Stefania; Petrolini, Melissa; Pagani, Elisabetta; Falini, Andrea; Comi, Giancarlo; Filippi, Massimo

    2012-09-01

    Leber's hereditary optic neuropathy (LHON) is a mitochondrial disease characterized by retinal ganglion cell degeneration and optic nerve atrophy, leading to a loss of central vision. The aim of this study was to explore the topographical pattern of damage to the brain white matter (WM) tracts from patients with chronic LHON using diffusion tensor (DT) MRI and tract-based spatial statistics (TBSS). Brain dual-echo and DT MRI scans were acquired from 13 patients with chronic LHON and 25 matched controls using a 3.0 T scanner. TBSS analysis was performed using the FMRIB's Diffusion Toolbox. A complete neuro-ophthalmologic examination, including standardized automated Humphrey perimetry as well as average and temporal peripapillary retinal nerve fiber layer thickness (PRNFL) measurements, was obtained in all patients. Mean average and temporal PRNFL thicknesses were decreased significantly in LHON patients. Compared to controls, TBSS analysis revealed significant diffusivity abnormalities in these patients, which were characterized by a decreased fractional anisotropy (FA) and an increased mean diffusivity and radial diffusivity, affecting exclusively the optic tracts and optic radiations (OR). In patients, a significant correlation was found between optic tract average FA and mean visual acuity (r = 0.57, p = 0.04). In LHON patients, DT MRI reveals a microstructural alteration of the WM along the entire visual pathways, with a sparing of the other main WM tracts of the brain. Damage to the OR may be secondary either to trans-synaptic degeneration, which in turn is due to neuroaxonal loss in the retina and optic nerve, or to local mitochondrial dysfunction.

  5. Reliability of clinician scoring of the landing error scoring system to assess jump-landing movement patterns.

    PubMed

    Markbreiter, Jessica G; Sagon, Bronson K; Valovich McLeod, Tamara C; Welch, Cailee E

    2015-05-01

    Clinical Scenario: An individual's movement patterns while landing from a jump can predispose him or her to lower-extremity injury, if performed improperly. The Landing Error Scoring System (LESS) is a clinical tool to assess jump-landing biomechanics as an individual jumps forward from a box. Improper movement patterns, which could predispose an individual to lower-extremity injuries, are scored as errors. However, because of the subjective nature of scoring errors during the task, the consistency and reliability of scoring the task are important. Since the LESS is a newer assessment tool, it is important to understand its reliability. Focused Clinical Question: Are clinicians reliable at scoring the LESS to assess jump-landing biomechanics of physically active individuals? PMID:25203628

  6. Spatial patterns and movements of red king and Tanner crabs: Implications for the design of marine protected areas

    USGS Publications Warehouse

    Taggart, S.J.; Mondragon, J.; Andrews, A.G.; Nielsen, J.K.

    2008-01-01

    Most examples of positive population responses to marine protected areas (MPAs) have been documented for tropical reef species with very small home ranges; the utility of MPAs for commercially harvested temperate species that have large movement patterns remains poorly tested. We measured the distribution and abundance of red king Paralithodes camtschaticus and Tanner Chionoecetes bairdi crabs inside and outside of MPAs in Glacier Bay National Park, Alaska, USA. By tagging a sub-sample of crabs with sonic tags, we estimated the movement of adult crabs from one of the MPAs (Muir Inlet) into the central portion of Glacier Bay where fishing still occurs. Tanner crabs and red king crabs moved similar average distances per day, although Tanner crabs had a higher transfer out of the Muir Inlet MPA into the central bay. Tanner crab movements were characterized by large variation among individual crabs, both in distance and direction traveled, while red king crabs migrated seasonally between 2 specific areas. Although Tanner crabs exhibited relatively large movements, distribution and abundance data suggest that they may be restricted at large spatial scales by habitat barriers. MPAs that are effective at protecting king and especially Tanner crab brood stock from fishing mortality will likely need to be larger than is typical of MPAs worldwide. However, by incorporating information on the seasonal movements of red king crabs and the location of habitat barriers for Tanner crabs, MPAs could likely be designed that would effectively protect adults from fishing mortality. ?? Inter-Research 2008.

  7. Dietary intake, food pattern, and abnormal blood glucose status of middle-aged adults: a cross-sectional community-based study in Myanmar

    PubMed Central

    Hlaing, Hlaing Hlaing; Liabsuetrakul, Tippawan

    2016-01-01

    Background Lifestyle changes, particularly dietary intake, had resulted in increasing trends of type-2 diabetes mellitus worldwide. However, dietary intake is diverse across country contexts. This study aimed to compare the dietary intake, food patterns, and blood glucose among middle-aged adults living in urban and suburban areas in Mandalay city, Myanmar, and explore their relationships. Methods A cross-sectional community-based study was conducted during June–November 2014. Adults aged 35–64 were randomly selected and requested to record all food they ate in a 4-day diary. Fasting and 2-hour postprandial blood glucose values were measured over two consecutive days. Dietary intakes were calculated in terms of energy, macronutrients, glycemic index, and glycemic load, and food patterns were identified by factor analysis. The relationships between food pattern, dietary intake, and blood glucose were assessed. Results Of 440 participants, dietary intake between urban and suburban residents was significantly different. Six food patterns were identified. There was no difference in fasting and 2-hour postprandial blood glucose between urban and suburban residents, but a strong correlation between fasting blood glucose and 2-hour postprandial blood glucose was found (correlation coefficient=0.8). Identification of abnormal blood glucose status using original fasting and converted 2-hour postprandial values showed substantial agreement (prevalence-adjusted bias-adjusted Kappa=0.8). Relationships between food patterns and blood glucose or abnormal blood glucose status were not found. Conclusion Food patterns were associated with dietary intake, not with abnormal blood glucose status. Two-hour postprandial blood glucose was highly correlated with fasting blood glucose and may be used for identifying abnormal blood glucose status. PMID:27150795

  8. Effects of Individual Differences in Verbal Skills on Eye-Movement Patterns during Sentence Reading

    ERIC Educational Resources Information Center

    Kuperman, Victor; Van Dyke, Julie A.

    2011-01-01

    This study is a large-scale exploration of the influence that individual reading skills exert on eye-movement behavior in sentence reading. Seventy-one non-college-bound 16-24 year-old speakers of English completed a battery of 18 verbal and cognitive skill assessments, and read a series of sentences as their eye-movements were monitored.…

  9. Do sleep abnormalities and misaligned sleep/circadian rhythm patterns represent early clinical characteristics for developing psychosis in high risk populations?

    PubMed

    Zanini, Marcio; Castro, Juliana; Coelho, Fernando Morgadinho; Bittencourt, Lia; Bressan, Rodrigo A; Tufik, Sergio; Brietzke, Elisa

    2013-12-01

    Sleep architecture changes, such as slow-wave sleep (SWS) percentage variations and reductions in latency and density of rapid eye movement (REM), are found in most patients with schizophrenia and are considered to be an important part of the pathophysiology of the disorder. In addition to these sleep parameters changes, disruptions in sleep homeostasis and the sleep/circadian rhythm also occur in these patients. Sleep/circadian rhythm abnormalities negatively affect neocortical plasticity and cognition and often precede the diagnosis of the illness. Thus, it has been suggested that the sleep/circadian rhythm might be involved in the pathophysiology of psychosis. Recent advances in the identification of individuals at a high risk for developing schizophrenia allow us to investigate several neurobiological processes involved in the development of psychosis. In this article, we review the current evidence of the effects of sleep parameter abnormalities, disruptions in sleep homeostasis and misalignments of sleep circadian rhythm on the early stages of schizophrenia. In addition, we discuss the preliminary evidence of sleep and circadian rhythm abnormalities during the prodromal stages of psychosis and propose that these abnormalities can be explored as potential predictors, as an adjunct to clinical diagnosis, of developing a psychotic disorder in at risk populations.

  10. Comparing movement patterns of satellite-tagged male and female polar bears

    USGS Publications Warehouse

    Amstrup, Steven C.; Durner, G.M.; McDonald, T.L.; Mulcahy, D.M.; Garner, G.W.

    2001-01-01

    Satellite radiotelemetry has provided great insights into the movements and behaviors of polar bears (Ursus maritimus). The diameter of the neck of adult male polar bears exceeds that of their head, however, and radio collars slip off. This has limited collection of movement information to that from radio-collared females. To overcome this difficulty and gather information about their movements, we surgically implanted satellite radio transmitters into 7 male polar bears during 1996 and 1997. We compared movements of implanted males with those of 104 adult females radio-collared between 1985 and 1995. Transmitters were implanted under the skin on the midline of the top of the neck and were equipped with percutaneous antennae. Implanted transmitters operated for up to 161 days providing 3217 satellite relocations. While transmitting, radios implanted in males provided a larger proportion of the highest quality category of position fixes than was obtained from radio-collared females. However, all implanted radios ceased transmitting before reaching their projected life-span. The abrupt termination of transmission from implanted radios suggested mechanical rather than electronic failure. Mean rates of short-term movement for males (1.18 km/h) were lower than for solitary females, females with cubs, and females with yearlings (1.70, 1.84, and 1.95 km/h, respectively). Net geographic movements from the beginning to the end of each month were comparable for males (mean = 135 km) and females (mean = 114, 152, and 168 km). Mean azimuths of these net movements also appeared to be similar. Monthly activity-area sizes for males (mean = 8541 km2) were comparable to those for females (mean = 3698, 9397, and 10 585 km2) during the time period of comparison. In contrast to the other movement measures, males traveled longer mean distances (387 km) each month than did females (217, 289, and 302 km). Movements of males, it appears, were more directed than those of females, but males

  11. Low relative error in consumer-grade GPS units make them ideal for measuring small-scale animal movement patterns

    PubMed Central

    Severns, Paul M.

    2015-01-01

    Consumer-grade GPS units are a staple of modern field ecology, but the relatively large error radii reported by manufacturers (up to 10 m) ostensibly precludes their utility in measuring fine-scale movement of small animals such as insects. Here we demonstrate that for data collected at fine spatio-temporal scales, these devices can produce exceptionally accurate data on step-length and movement patterns of small animals. With an understanding of the properties of GPS error and how it arises, it is possible, using a simple field protocol, to use consumer grade GPS units to collect step-length data for the movement of small animals that introduces a median error as small as 11 cm. These small error rates were measured in controlled observations of real butterfly movement. Similar conclusions were reached using a ground-truth test track prepared with a field tape and compass and subsequently measured 20 times using the same methodology as the butterfly tracking. Median error in the ground-truth track was slightly higher than the field data, mostly between 20 and 30 cm, but even for the smallest ground-truth step (70 cm), this is still a signal-to-noise ratio of 3:1, and for steps of 3 m or more, the ratio is greater than 10:1. Such small errors relative to the movements being measured make these inexpensive units useful for measuring insect and other small animal movements on small to intermediate scales with budgets orders of magnitude lower than survey-grade units used in past studies. As an additional advantage, these units are simpler to operate, and insect or other small animal trackways can be collected more quickly than either survey-grade units or more traditional ruler/gird approaches. PMID:26312190

  12. Passive acoustic telemetry reveals highly variable home range and movement patterns among unicornfish within a marine reserve

    NASA Astrophysics Data System (ADS)

    Marshell, A.; Mills, J. S.; Rhodes, K. L.; McIlwain, J.

    2011-09-01

    Marine reserves are the primary management tool for Guam's reef fish fishery. While a build-up of fish biomass has occurred inside reserve boundaries, it is unknown whether reserve size matches the scale of movement of target species. Using passive acoustic telemetry, we quantified movement patterns and home range size of two heavily exploited unicornfish Naso unicornis and Naso lituratus. Fifteen fish ( N. unicornis: n = 7; N. lituratus: n = 4 male, n = 4 female) were fitted with internal acoustic tags and tracked continuously over four months within a remote acoustic receiver array located in a decade-old marine reserve. This approach provided robust estimates of unicornfish movement patterns and home range size. The mean home range of 3.2 ha for N. unicornis was almost ten times larger than that previously recorded from a three-week tracking study of the species in Hawaii. While N. lituratus were smaller in body size, their mean home range (6.8 ha) was over twice that of N. unicornis. Both species displayed strong site fidelity, particularly during nocturnal and crepuscular periods. Although there was some overlap, individual movement patterns and home range size were highly variable within species and between sexes. N. unicornis home range increased with body size, and only the three largest fish home ranges extended into the deeper outer reef slope beyond the shallow reef flat. Both Naso species favoured habitat dominated by corals. Some individuals made predictable daily crepuscular migrations between different locations or habitat types. There was no evidence of significant spillover from the marine reserve into adjacent fished areas. Strong site fidelity coupled with negligible spillover suggests that small-scale reserves, with natural habitat boundaries to emigration, are effective in protecting localized unicornfish populations.

  13. Correlated biased random walk with latency in one and two dimensions: Asserting patterned and unpredictable movement

    NASA Astrophysics Data System (ADS)

    Rodriguez-Horta, E.; Estevez-Rams, E.; Lora-Serrano, R.; Fernández, B. Aragón

    2016-09-01

    The correlated biased random walk with latency in one and two dimensions is discussed with regard to the portion of irreducible random movement and structured movement. It is shown how a quantitative analysis can be carried out by using computational mechanics. The stochastic matrix for both dynamics are reported. Latency introduces new states in the finite state machine description of the system in both dimensions, allowing for a full nearest neighbor coordination in the two dimensional case. Complexity analysis is used to characterize the movement, independently of the set of control parameters, making it suitable for the discussion of other random walk models. The complexity map of the system dynamics is reported for the two dimensional case.

  14. Movement patterns of Antillean manatees in Chetumal Bay (Mexico) and coastal Belize: A challenge for regional conservation

    USGS Publications Warehouse

    Castelblanco-Martínez, Delma Nataly; Padilla-Saldivar, J.; Hernández-Arana, Héctor Abuid; Slone, D.H.; Reid, J.P.; Morales-Vela, B.

    2013-01-01

    Information from 15 satellite-tracked Antillean manatees (Trichechus manatus manatus) was analyzed in order to assess individual movements, home ranges, and high-use areas for conservation decisions. Manatees were captured in Chetumal Bay, Mexico, and tagged with Argos-monitored satellite transmitters. Location of the manatees and physical characteristics were assessed to describe habitat properties. Most manatees traveled to freshwater sources. The Maximum Area Size (MAS) for each manatee was determined using the observation-area method. Additional kernel densities of 95% home range and 50% Center of Activity (COA) were also calculated, with manatees having 1–3 COAs. Manatees exhibited two different movement patterns: remaining in Chetumal Bay, and long-distance (up to 240 km in 89 d). The residence time in Chetumal Bay was higher for females (89.6% of time) than for males (72.0%), but the daily travel rate (0.4–0.5 km/d) was similar for both sexes. Most of the COAs fell within Natural Protected Areas (NPA). However, manatees also travel for long distances into unprotected areas, where they face uncontrolled boat traffic, fishing activities, and habitat loss. Conservation of movement corridors may promote long-distance movements and facilitate genetic exchange.

  15. Environmental influences on patterns of vertical movement and site fidelity of grey reef sharks (Carcharhinus amblyrhynchos) at aggregation sites.

    PubMed

    Vianna, Gabriel M S; Meekan, Mark G; Meeuwig, Jessica J; Speed, Conrad W

    2013-01-01

    We used acoustic telemetry to describe the patterns of vertical movement, site fidelity and residency of grey reef sharks (Carcharhinus amblyrhynchos) on the outer slope of coral reefs in Palau, Micronesia, over a period of two years and nine months. We tagged 39 sharks (mostly adult females) of which 31 were detected regularly throughout the study. Sharks displayed strong inter-annual residency with greater attendance at monitored sites during summer than winter months. More individuals were detected during the day than at night. Mean depths of tagged sharks increased from 35 m in winter to 60 m in spring following an increase in water temperature at 60 m, with maximum mean depths attained when water temperatures at 60 m stabilised around 29°C. Sharks descended to greater depths and used a wider range of depths around the time of the full moon. There were also crepuscular cycles in mean depth, with sharks moving into shallower waters at dawn and dusk each day. We suggest that daily, lunar and seasonal cycles in vertical movement and residency are strategies for optimising both energetic budgets and foraging behaviour. Cyclical patterns of movement in response to environmental variables might affect the susceptibility of reef sharks to fishing, a consideration that should be taken into account in the implementation of conservation strategies.

  16. Structural and Dynamical Patterns on Online Social Networks: The Spanish May 15th Movement as a Case Study

    PubMed Central

    Borge-Holthoefer, Javier; Rivero, Alejandro; García, Iñigo; Cauhé, Elisa; Ferrer, Alfredo; Ferrer, Darío; Francos, David; Iñiguez, David; Pérez, María Pilar; Ruiz, Gonzalo; Sanz, Francisco; Serrano, Fermín; Viñas, Cristina; Tarancón, Alfonso; Moreno, Yamir

    2011-01-01

    The number of people using online social networks in their everyday life is continuously growing at a pace never saw before. This new kind of communication has an enormous impact on opinions, cultural trends, information spreading and even in the commercial success of new products. More importantly, social online networks have revealed as a fundamental organizing mechanism in recent country-wide social movements. In this paper, we provide a quantitative analysis of the structural and dynamical patterns emerging from the activity of an online social network around the ongoing May 15th (15M) movement in Spain. Our network is made up by users that exchanged tweets in a time period of one month, which includes the birth and stabilization of the 15M movement. We characterize in depth the growth of such dynamical network and find that it is scale-free with communities at the mesoscale. We also find that its dynamics exhibits typical features of critical systems such as robustness and power-law distributions for several quantities. Remarkably, we report that the patterns characterizing the spreading dynamics are asymmetric, giving rise to a clear distinction between information sources and sinks. Our study represents a first step towards the use of data from online social media to comprehend modern societal dynamics. PMID:21886834

  17. Environmental influences on patterns of vertical movement and site fidelity of grey reef sharks (Carcharhinus amblyrhynchos) at aggregation sites.

    PubMed

    Vianna, Gabriel M S; Meekan, Mark G; Meeuwig, Jessica J; Speed, Conrad W

    2013-01-01

    We used acoustic telemetry to describe the patterns of vertical movement, site fidelity and residency of grey reef sharks (Carcharhinus amblyrhynchos) on the outer slope of coral reefs in Palau, Micronesia, over a period of two years and nine months. We tagged 39 sharks (mostly adult females) of which 31 were detected regularly throughout the study. Sharks displayed strong inter-annual residency with greater attendance at monitored sites during summer than winter months. More individuals were detected during the day than at night. Mean depths of tagged sharks increased from 35 m in winter to 60 m in spring following an increase in water temperature at 60 m, with maximum mean depths attained when water temperatures at 60 m stabilised around 29°C. Sharks descended to greater depths and used a wider range of depths around the time of the full moon. There were also crepuscular cycles in mean depth, with sharks moving into shallower waters at dawn and dusk each day. We suggest that daily, lunar and seasonal cycles in vertical movement and residency are strategies for optimising both energetic budgets and foraging behaviour. Cyclical patterns of movement in response to environmental variables might affect the susceptibility of reef sharks to fishing, a consideration that should be taken into account in the implementation of conservation strategies. PMID:23593193

  18. Environmental Influences on Patterns of Vertical Movement and Site Fidelity of Grey Reef Sharks (Carcharhinus amblyrhynchos) at Aggregation Sites

    PubMed Central

    Vianna, Gabriel M. S.; Meekan, Mark G.; Meeuwig, Jessica J.; Speed, Conrad W.

    2013-01-01

    We used acoustic telemetry to describe the patterns of vertical movement, site fidelity and residency of grey reef sharks (Carcharhinus amblyrhynchos) on the outer slope of coral reefs in Palau, Micronesia, over a period of two years and nine months. We tagged 39 sharks (mostly adult females) of which 31 were detected regularly throughout the study. Sharks displayed strong inter-annual residency with greater attendance at monitored sites during summer than winter months. More individuals were detected during the day than at night. Mean depths of tagged sharks increased from 35 m in winter to 60 m in spring following an increase in water temperature at 60 m, with maximum mean depths attained when water temperatures at 60 m stabilised around 29°C. Sharks descended to greater depths and used a wider range of depths around the time of the full moon. There were also crepuscular cycles in mean depth, with sharks moving into shallower waters at dawn and dusk each day. We suggest that daily, lunar and seasonal cycles in vertical movement and residency are strategies for optimising both energetic budgets and foraging behaviour. Cyclical patterns of movement in response to environmental variables might affect the susceptibility of reef sharks to fishing, a consideration that should be taken into account in the implementation of conservation strategies. PMID:23593193

  19. Microarray analysis of microRNA expression patterns in the semen of infertile men with semen abnormalities.

    PubMed

    Liu, Te; Cheng, Weiwei; Gao, Yongtao; Wang, Hui; Liu, Zhixue

    2012-09-01

    MicroRNAs (miRNAs) play a crucial role in tissue development and the pathology of many diseases, however, the effects and roles of miRNAs in the development of semen abnormalities in infertile males have not yet been investigated. In this study, we analyzed and compared the miRNA expression profiles of abnormal semen from 86 infertile males with normal semen from 86 healthy males using an miRNA microarray. In total, 52 miRNAs were differentially expressed between the abnormal semen of infertile males and the normal semen of healthy males. The differential expression of selected miRNAs was validated by real time qRT-PCR and northern blotting: miR-574-5p, miR-297, miR-122, miR-1275, miR-373, miR-185 and miR-193b were upregulated (fold change>1.5, p<0.001) and miR-100, miR-512-3p, miR-16, miR-19b, miR-23b and miR-26a were downregulated (fold change<0.667, p<0.001) in the semen of infertile males with semen abnormalities. In conclusion, this study provides new insights into specific miRNAs that are associated with semen abnormalities in infertile males.

  20. 3. Mass Movements, Erosion Patterns and Sediment Transport along the Sutlej River (NW-Himalaya)

    NASA Astrophysics Data System (ADS)

    Bookhagen, B.; Thiede, R. C.; Strecker, M. R.

    2003-04-01

    The spatial and temporal distribution of mass movements in active orogens can provide valuable insights into the relation between sedimentation and erosion processes. In areas of high relief, hillslope processes dominate surface geomorphology and can lead to the damming of rivers and formation of lakes upstream. These basins provide a record of natural climatic variations along the river profile and divide the regions in different sedimentational and erosional compartments. To characterize the variations, digital elevation models were used for quantitative analysis of topography, basin-fill volume, and active channel gradients. High-resolution spatial data (digitized 1:25,000 to 1:100,000 topographic maps) and ASTER-derived digital elevation models (DEM) were processed to analyze topography. Combined with geological field measurements and observations we could distinguish erosional patterns within several study areas in the NW Himalayas. Precipitation data were derived from calibrated passive microwave satellite data (SSMI), providing information on a 10 year time series at sufficient spatial resolution (12.5 km2). Modern sediment flux and transport, discharge, geomorphic field observations including river width and slope define the boundary conditions for surface erosion calculations. The Sutlej Valley (32N, 78E) in NW India is dominated by the antecedent Sutlej River, the third-largest river in the Himalayas. It flows perpendicular through the orogen and cuts through all major geologic units of the Tethyan Himalaya, High and Lesser Himalayan Crystallines, and Lower Himalayan units. The geomorphologic changes across thrust faults bounding these units provide valuable insights into the evolution of the orogen. Tectonically active sectors of the orogen are manifested by pronounced knickpoints in longitudinal river profiles that cross active thrust faults. In contrast to other parts of the Himalayas, no (re-) activation of the MCT and STDS can be seen in the

  1. Eye-Movement Patterns Are Associated with Communicative Competence in Autistic Spectrum Disorders

    ERIC Educational Resources Information Center

    Norbury, Courtenay Frazier; Brock, Jon; Cragg, Lucy; Einav, Shiri; Griffiths, Helen; Nation, Kate

    2009-01-01

    Background: Investigations using eye-tracking have reported reduced fixations to salient social cues such as eyes when participants with autism spectrum disorders (ASD) view social scenes. However, these studies have not distinguished different cognitive phenotypes. Methods: The eye-movements of 28 teenagers with ASD and 18 typically developing…

  2. Respiratory Movement Patterns during Vocalizations at 7 and 11 Months of Age

    ERIC Educational Resources Information Center

    Reilly, Kevin J.; Moore, Christopher A.

    2009-01-01

    Purpose: The present investigation was designed to study the modulation of abdomen and rib cage movements during vocalization over a period of development associated with rapid decreases in the compliance of the chest wall. Method: Rib cage and abdominal kinematics were recorded during spontaneous vocalizations in 7- and 11-month old infants.…

  3. Visual Data Mining: An Exploratory Approach to Analyzing Temporal Patterns of Eye Movements

    ERIC Educational Resources Information Center

    Yu, Chen; Yurovsky, Daniel; Xu, Tian

    2012-01-01

    Infant eye movements are an important behavioral resource to understand early human development and learning. But the complexity and amount of gaze data recorded from state-of-the-art eye-tracking systems also pose a challenge: how does one make sense of such dense data? Toward this goal, this article describes an interactive approach based on…

  4. Pigment cell movement is not required for generation of Turing patterns in zebrafish skin

    PubMed Central

    Bullara, D.; De Decker, Y.

    2015-01-01

    The zebrafish is a model organism for pattern formation in vertebrates. Understanding what drives the formation of its coloured skin motifs could reveal pivotal to comprehend the mechanisms behind morphogenesis. The motifs look and behave like reaction–diffusion Turing patterns, but the nature of the underlying physico-chemical processes is very different, and the origin of the patterns is still unclear. Here we propose a minimal model for such pattern formation based on a regulatory mechanism deduced from experimental observations. This model is able to produce patterns with intrinsic wavelength, closely resembling the experimental ones. We mathematically prove that their origin is a Turing bifurcation occurring despite the absence of cell motion, through an effect that we call differential growth. This mechanism is qualitatively different from the reaction–diffusion originally proposed by Turing, although they both generate the short-range activation and the long-range inhibition required to form Turing patterns. PMID:25959141

  5. Pigment cell movement is not required for generation of Turing patterns in zebrafish skin

    NASA Astrophysics Data System (ADS)

    Bullara, D.; de Decker, Y.

    2015-05-01

    The zebrafish is a model organism for pattern formation in vertebrates. Understanding what drives the formation of its coloured skin motifs could reveal pivotal to comprehend the mechanisms behind morphogenesis. The motifs look and behave like reaction-diffusion Turing patterns, but the nature of the underlying physico-chemical processes is very different, and the origin of the patterns is still unclear. Here we propose a minimal model for such pattern formation based on a regulatory mechanism deduced from experimental observations. This model is able to produce patterns with intrinsic wavelength, closely resembling the experimental ones. We mathematically prove that their origin is a Turing bifurcation occurring despite the absence of cell motion, through an effect that we call differential growth. This mechanism is qualitatively different from the reaction-diffusion originally proposed by Turing, although they both generate the short-range activation and the long-range inhibition required to form Turing patterns.

  6. Stable isotopes in barnacles as a tool to understand green sea turtle (Chelonia mydas) regional movement patterns

    NASA Astrophysics Data System (ADS)

    Detjen, M.; Sterling, E.; Gómez, A.

    2015-12-01

    Sea turtles are migratory animals that travel long distances between their feeding and breeding grounds. Traditional methods for researching sea turtle migratory behavior have important disadvantages, and the development of alternatives would enhance our ability to monitor and manage these globally endangered species. Here we report on the isotope signatures in green sea-turtle (Chelonia mydas) barnacles (Platylepas sp.) and discuss their potential relevance as tools with which to study green sea turtle migration and habitat use patterns. We analyzed oxygen (δ18O) and carbon (δ13C) isotope ratios in barnacle calcite layers from specimens collected from green turtles captured at the Palmyra Atoll National Wildlife Refuge (PANWR) in the central Pacific. Carbon isotopes were not informative in this study. However, the oxygen isotope results suggest likely regional movement patterns when mapped onto a predictive oxygen isotope map of the Pacific. Barnacle proxies could therefore complement other methods in understanding regional movement patterns, informing more effective conservation policy that takes into account connectivity between populations.

  7. Stable isotopes in barnacles as a tool to understand green sea turtle (Chelonia mydas) regional movement patterns

    NASA Astrophysics Data System (ADS)

    Detjen, M.; Sterling, E.; Gómez, A.

    2015-03-01

    Sea turtles are migratory animals that travel long distances between their feeding and breeding grounds. Traditional methods for researching sea turtle migratory behavior have important disadvantages, and the development of alternatives would enhance our ability to monitor and manage these globally endangered species. Here we report on the isotope signatures in green sea turtle (Chelonia mydas) barnacles (Platylepas sp.) and discuss their potential relevance as tools with which to study green sea turtle migration and habitat use patterns. We analyzed oxygen (δ18O) and carbon (δ13C) isotope ratios in barnacle calcite layers from specimens collected from green turtles captured at the Palmyra Atoll National Wildlife Refuge (PANWR) in the Central Pacific. Carbon isotopes were not informative in this study. However, the oxygen isotope results suggest likely regional movement patterns when mapped onto a predictive oxygen isotope map of the Pacific. Barnacle proxies could therefore complement other methods in understanding regional movement patterns, informing more effective conservation policy that takes into account connectivity between populations.

  8. [The stability of complete dentures in the construction of functional movement patterns].

    PubMed

    Landeck, E

    1978-07-01

    In a cross-sectional study involving 185 full denture wearers, the stability of upper and lower dentures was determined by means of active test movements according to Herbst. The percentages of instable dentures and their confidence intervals were calculated. It was found that all sections of upper full dentures can be regarded as equal with regard to stability, whereas the sections of lower full dentures showed considerable differences. Finally, practice-relevant conclusions are drawn from the results of the present study.

  9. Three-year movement patterns of adult desert tortoises at Yucca Mountain

    SciTech Connect

    Holt, E.A.; Rautenstrauch, K.R.

    1995-12-31

    We studied the home-range size and site fidelity of adult desert tortoises (Gopherus agassizii) at Yucca Mountain, Nevada, during 1992-1994. Of 67 adult tortoises monitored at Yucca Mountain during this period, we evaluated the movements of 22 female and 16 male radiomarked tortoises that were located >50 times during each of the 1992, 1993, and 1994 activity seasons. We measured annual and three-year home range sizes by either 100% minimum convex polygon (MCP) or by 95% cluster.

  10. Relationships between spatial patterns of colonic pressure and individual movements of content.

    PubMed

    Cook, I J; Furukawa, Y; Panagopoulos, V; Collins, P J; Dent, J

    2000-02-01

    The aim of this study was to examine the relationship between colonic pressure waves and movement of content. In 11 healthy subjects, pressures were recorded at 10-cm intervals from cecum to rectum for 32 h. In six subjects, transit was simultaneously measured for 8 h after direct cecal instillation of 1.5 mCi of (99m)Tc sulfur colloid. Thirty-two percent of isotope movements were related to nonpropagating activity and twenty-eight percent to propagating sequences. The extent of isotope movement related to propagating sequences (25.1 +/- 2.1 cm) was greater than that due to nonpropagating activity (12.8 +/- 0.7 cm; P = 0.0001). Propagating sequences originated significantly more frequently (P = 0.004) and propagated further (P = 0.0006) in the proximal compared with the distal colon. Only 36% of propagating sequences were propulsive of content, and compared with nonpropulsive sequences, these propagated further (41 +/- 6 vs. 27 +/- 2 cm; P < 0.05) and had a higher probability of originating proximally (P = 0.0003), a higher pressure wave amplitude (50 +/- 5 vs. 34 +/- 4 mmHg; P = 0.0001), and slower velocity (2.2 +/- 0.3 vs. 3.6 +/- 0.47 cm/s; P = 0.02). We conclude that most movements of colonic content are related to pressure waves. There is marked regional variation in the prevalence, velocity, and extent of propagation of propagating pressure wave sequences, which are an important mechanism for transporting content over long distances. The effectiveness of transport by a propagating sequence is influenced by its site of origin, amplitude, and velocity.

  11. The eye of the beholder: Can patterns in eye movement reveal aptitudes for spatial reasoning?

    PubMed

    Roach, Victoria A; Fraser, Graham M; Kryklywy, James H; Mitchell, Derek G V; Wilson, Timothy D

    2016-07-01

    Mental rotation ability (MRA) is linked to academic success in the spatially complex Science, Technology, Engineering, Medicine, and Mathematics (STEMM) disciplines, and anatomical sciences. Mental rotation literature suggests that MRA may manifest in the movement of the eyes. Quantification of eye movement data may serve to distinguish MRA across individuals, and serve as a consideration when designing visualizations for instruction. It is hypothesized that high-MRA individuals will demonstrate fewer eye fixations, conduct shorter average fixation durations (AFD), and demonstrate shorter response times, than low-MRA individuals. Additionally, individuals with different levels of MRA will attend to different features of the block-figures presented in the electronic mental rotations test (EMRT). All participants (n = 23) completed the EMRT while metrics of eye movement were collected. The test required participants view pairs of three-dimensional (3D) shapes, and identify if the pair is rotated but identical, or two different structures. Temporal analysis revealed no significant correlations between response time, average fixation durations, or number of fixations and mental rotation ability. Further analysis of within-participant variability yielded a significant correlation for response time variability, but no correlation between AFD variability and variability in the number of fixations. Additional analysis of salience revealed that during problem solving, individuals of differing MRA attended to different features of the block images; suggesting that eye movements directed at salient features may contribute to differences in mental rotations ability, and may ultimately serve to predict success in anatomy. Anat Sci Educ 9: 357-366. © 2015 American Association of Anatomists. PMID:26599398

  12. The Daily Movement Pattern and Fulfilment of Physical Activity Recommendations in Swedish Middle-Aged Adults: The SCAPIS Pilot Study.

    PubMed

    Ekblom-Bak, Elin; Olsson, Gustav; Ekblom, Örjan; Ekblom, Björn; Bergström, Göran; Börjesson, Mats

    2015-01-01

    Different aspects of the daily movement pattern--sitting, light intensity physical activity, and moderate- and vigorous intensity physical activity--have each independently been associated with health and longevity. Previous knowledge of the amount and distribution of these aspects in the general Swedish population, as well as the fulfilment rate of physical activity recommendations, mainly relies on self-reported data. More detailed data assessed with objective methods is needed. The aim of the study was to present descriptive data on the daily movement pattern in a middle-aged Swedish population assessed by hip-worn accelerometers. The cohort consisted of 948 participants (51% women), aged 50 to 64 years, from the Swedish CArdioPulmonary bioImage pilot Study. In the total sample, 60.5% of accelerometer wear time was spent sitting, 35.2% in light physical activity and 3.9% in moderate- and vigorous physical activity. Men and participants with high educational level spent a larger proportion of time sitting, compared to women and participants with low educational level. Men and participants with a high educational level spent more time, and the oldest age-group spent less time, in moderate- and vigorous physical activity. Only 7.1% of the study population met the current national physical activity recommendations, with no gender, age or education level differences. Assessment of all three components of the daily movement pattern is of high clinical relevance and should be included in future research. As the fulfilment of national physical activity recommendations is very low and sitting time is very high in our middle-aged population, the great challenge remains to enhance the implementation of methods to increase the level of physical activity in this population.

  13. Spatiotemporal patterns, annual baseline and movement-related incidence of Streptococcus agalactiae infection in Danish dairy herds: 2000-2009.

    PubMed

    Mweu, Marshal M; Nielsen, Søren S; Halasa, Tariq; Toft, Nils

    2014-02-01

    Several decades after the inception of the five-point plan for the control of contagious mastitis pathogens, Streptococcus agalactiae (S. agalactiae) persists as a fundamental threat to the dairy industry in many countries. A better understanding of the relative importance of within- and between-herd sources of new herd infections coupled with the spatiotemporal distribution of the infection, may aid in effective targeting of control efforts. Thus, the objectives of this study were: (1) to describe the spatiotemporal patterns of infection with S. agalactiae in the population of Danish dairy herds from 2000 to 2009 and (2) to estimate the annual herd-level baseline and movement-related incidence risks of S. agalactiae infection over the 10-year period. The analysis involved registry data on bacteriological culture of all bulk tank milk samples collected as part of the mandatory Danish S. agalactiae surveillance scheme as well as live cattle movements into dairy herds during the specified 10-year period. The results indicated that the predicted risk of a herd becoming infected with S. agalactiae varied spatiotemporally; the risk being more homogeneous and higher in the period after 2005. Additionally, the annual baseline risks yielded significant yet distinctive patterns before and after 2005 - the risk of infection being higher in the latter phase. On the contrary, the annual movement-related risks revealed a non-significant pattern over the 10-year period. There was neither evidence for spatial clustering of cases relative to the population of herds at risk nor spatial dependency between herds. Nevertheless, the results signal a need to beef up within-herd biosecurity in order to reduce the risk of new herd infections. PMID:24269038

  14. Movement patterns of Brook Trout in a restored coastal stream system in southern Massachusetts

    USGS Publications Warehouse

    Snook, Erin L.; Letcher, Benjamin H.; Dubreuil, Todd L.; Zydlewski, Joseph; O'Donnell, Matthew J.; Whiteley, Andrew R.; Hurley, Stephen T.; Danylchuk, Andy J.

    2016-01-01

    Coastal Brook Trout (Salvelinus fontinalis) populations are found from northern Canada to New England. The extent of anadromy generally decreases with latitude, but the ecology and movements of more southern populations are poorly understood. We conducted a 33-month acoustic telemetry study of Brook Trout in Red Brook, MA, and adjacent Buttermilk Bay (marine system) using 16 fixed acoustic receivers and surgically implanting acoustic transmitters in 84 individuals. Tagged Brook Trout used the stream, estuary (50% of individuals) and bay (10% of individuals). Movements into full sea water were brief when occurring. GAMM models revealed that transitions between habitat areas occurred most often in spring and fall. Environmental data suggest that use of the saline environment is limited by summer temperatures in the bay. Movements may also be related to moon phase. Compared to more northern coastal populations of Brook Trout, the Red Brook population appears to be less anadromous overall, yet the estuarine segment of the system may have considerable ecological importance as a food resource.

  15. Regional movement patterns of a small-bodied shark revealed by stable-isotope analysis.

    PubMed

    Munroe, S E M; Heupel, M R; Fisk, A T; Logan, M; Simpfendorfer, C A

    2015-05-01

    This study used stable-isotope analysis to define the nearshore regional residency and movements of the small-bodied Australian sharpnose shark Rhizoprionodon taylori. Plasma and muscle δ(13) C and δ(15) N of R. taylori were collected from across five embayments and compared with values of seagrass and plankton from each bay. Linear distances between adjacent bays ranged from 30 to 150 km. There was a positive geographic correlation between R. taylori tissue and environmental δ(13) C values. Populations with the highest tissue δ(15) N were collected from bays that had the highest environmental δ(15) N values. These results suggest that R. taylori did not forage more than 100 km away from their capture location within 6 months to 1 year. The successful application of isotope analysis to define R. taylori movement demonstrates that this technique may be used in addition to traditional methods to study the movement of sharks, even within similar habitats across regionally small spatial scales (<100 km). PMID:25846994

  16. Action Recognition and Movement Direction Discrimination Tasks Are Associated with Different Adaptation Patterns.

    PubMed

    de la Rosa, Stephan; Ekramnia, Mina; Bülthoff, Heinrich H

    2016-01-01

    The ability to discriminate between different actions is essential for action recognition and social interactions. Surprisingly previous research has often probed action recognition mechanisms with tasks that did not require participants to discriminate between actions, e.g., left-right direction discrimination tasks. It is not known to what degree visual processes in direction discrimination tasks are also involved in the discrimination of actions, e.g., when telling apart a handshake from a high-five. Here, we examined whether action discrimination is influenced by movement direction and whether direction discrimination depends on the type of action. We used an action adaptation paradigm to target action and direction discrimination specific visual processes. In separate conditions participants visually adapted to forward and backward moving handshake and high-five actions. Participants subsequently categorized either the action or the movement direction of an ambiguous action. The results showed that direction discrimination adaptation effects were modulated by the type of action but action discrimination adaptation effects were unaffected by movement direction. These results suggest that action discrimination and direction categorization rely on partly different visual information. We propose that action discrimination tasks should be considered for the exploration of visual action recognition mechanisms.

  17. Abnormal Fatty Acid Pattern in the Superior Temporal Gyrus Distinguishes Bipolar Disorder from Major Depression and Schizophrenia and Resembles Multiple Sclerosis

    PubMed Central

    McNamara, Robert K.; Rider, Therese; Jandacek, Ronald; Tso, Patrick

    2014-01-01

    This study investigated the fatty acid composition of the postmortem superior temporal gyrus (STG), a cortical region implicated in emotional processing, from normal controls (n=15) and patients with bipolar disorder (BD, n=15), major depressive disorder (MDD, n=15), and schizophrenia (SZ, n=15). For comparative purposes, STG fatty acid composition was determined in a separate cohort of multiple sclerosis patients (MS, n=15) and normal controls (n=15). Compared with controls, patients with BD, but not MDD or SZ, exhibited abnormal elevations in the saturated fatty acids (SFA) palmitic acid (16:0), stearic acid (18:0), the polyunsaturated fatty acids (PUFA) linoleic acid (18:2n-6), arachidonic acid (20:4n-6), and docosahexaenoic acid (22:6n-3), and reductions in the monounsaturated fatty acid (MUFA) oleic acid (18:1n-9). The total MUFA/SFA and 18:1/18:0 ratios were lower in the STG of BD patients and were inversely correlated with total PUFA composition. MS patients exhibited a pattern of fatty acid abnormalities similar to that observed in BD patients including elevated PUFA and a lower 18:1/18:0 ratio. Collectively, these data demonstrate that BD patients exhibit a pattern of fatty acid abnormalities in the STG that is not observed in MDD and SZ patients and closely resembles MS patients. PMID:24439517

  18. Texture analysis of collagen second-harmonic generation images based on local difference local binary pattern and wavelets differentiates human skin abnormal scars from normal scars

    NASA Astrophysics Data System (ADS)

    Liu, Yao; Zhu, Xiaoqin; Huang, Zufang; Cai, Jianyong; Chen, Rong; Xiong, Shuyuan; Chen, Guannan; Zeng, Haishan

    2015-01-01

    Quantitative methods for noninvasive diagnosis of scars are a challenging issue in medicine. This work aims to implement a texture analysis method for quantitatively discriminating abnormal scars from normal scars based on second-harmonic generation (SHG) images. A local difference local binary pattern (LD-LBP) operator combined with a wavelet transform was explored to extract diagnosis features from scar SHG images that were related to the alteration in collagen morphology. Based on the quantitative parameters including the homogeneity, directional and coarse features in SHG images, the scar collagen SHG images were classified into normal or abnormal scars by a support vector machine classifier in a leave-one-out cross-validation procedure. Our experiments and data analyses demonstrated apparent differences between normal and abnormal scars in terms of their morphological structure of collagen. By comparing with gray level co-occurrence matrix, wavelet transform, and combined basic local binary pattern and wavelet transform with respect to the accuracy and receiver operating characteristic analysis, the method proposed herein was demonstrated to achieve higher accuracy and more reliable classification of SHG images. This result indicated that the extracted texture features with the proposed method were effective in the classification of scars. It could provide assistance for physicians in the diagnostic process.

  19. Eye movements and visuoverbal descriptions exhibit heterogeneous and dissociated patterns before and after prismatic adaptation in unilateral spatial neglect.

    PubMed

    Datié, A-M; Paysant, J; Destainville, S; Sagez, A; Beis, J-M; André, J-M

    2006-07-01

    This prospective study examined the effects of prismatic adaptation on visual exploration strategies in patients with left unilateral spatial neglect (USN). Photo-oculographic gaze recordings were obtained, as the subjects (28 brain-damaged; 15 control) performed a free visual exploration task before and after a session of prismatic adaptation. (i) Before prismatic adaptation, the pattern of visual exploration described two subgroups of patients (symmetrical exploration of hemispaces - similar to the control subjects, deficient exploration of left hemispace). Twelve of 20 patients failed to describe significant elements in the left part of the displayed image. Several visuoverbal patterns were observed, some dissociating visual exploration and verbal description. (ii) Immediately after prismatic adaptation, patients with asymmetrical visual exploration presented a significant increase in the number of point fixations and saccades in the left hemispace. Patients with symmetrical exploration presented the opposite pattern. Improved pattern of visual exploration contrasted with an absence of improved verbal description. Eye movements and visuoverbal descriptions exhibit heterogeneous and dissociated patterns before and after prismatic adaptation. This results demonstrate that prismatic adaptation has no effect in certain patients, suggesting that therapeutic indications and evaluation of prismatic test results should take into consideration the heterogeneous nature of USN.

  20. The movements made by performers in a skilled quartet: a distinctive pattern, and the function that it serves.

    PubMed

    Glowinski, Donald; Mancini, Maurizio; Cowie, Roddy; Camurri, Antonio; Chiorri, Carlo; Doherty, Cian

    2013-01-01

    When people perform a task as part of a joint action, their behavior is not the same as it would be if they were performing the same task alone, since it has to be adapted to facilitate shared understanding (or sometimes to prevent it). Joint performance of music offers a test bed for ecologically valid investigations of the way non-verbal behavior facilitates joint action. Here we compare the expressive movement of violinists when playing in solo and ensemble conditions. The first violinists of two string quartets (SQs), professional and student, were asked to play the same musical fragments in a solo condition and with the quartet. Synchronized multimodal recordings were created from the performances, using a specially developed software platform. Different patterns of head movement were observed. By quantifying them using an appropriate measure of entropy, we showed that head movements are more predictable in the quartet scenario. Rater evaluations showed that the change does not, as might be assumed, entail markedly reduced expression. They showed some ability to discriminate between solo and ensemble performances, but did not distinguish them in terms of emotional content or expressiveness. The data raise provocative questions about joint action in realistically complex scenarios. PMID:24312065

  1. The movements made by performers in a skilled quartet: a distinctive pattern, and the function that it serves

    PubMed Central

    Glowinski, Donald; Mancini, Maurizio; Cowie, Roddy; Camurri, Antonio; Chiorri, Carlo; Doherty, Cian

    2013-01-01

    When people perform a task as part of a joint action, their behavior is not the same as it would be if they were performing the same task alone, since it has to be adapted to facilitate shared understanding (or sometimes to prevent it). Joint performance of music offers a test bed for ecologically valid investigations of the way non-verbal behavior facilitates joint action. Here we compare the expressive movement of violinists when playing in solo and ensemble conditions. The first violinists of two string quartets (SQs), professional and student, were asked to play the same musical fragments in a solo condition and with the quartet. Synchronized multimodal recordings were created from the performances, using a specially developed software platform. Different patterns of head movement were observed. By quantifying them using an appropriate measure of entropy, we showed that head movements are more predictable in the quartet scenario. Rater evaluations showed that the change does not, as might be assumed, entail markedly reduced expression. They showed some ability to discriminate between solo and ensemble performances, but did not distinguish them in terms of emotional content or expressiveness. The data raise provocative questions about joint action in realistically complex scenarios. PMID:24312065

  2. Movement patterns and population characteristics of the Karner blue butterfly (Lycaeides melissa samuelis) at Indiana Dunes National Lakeshore

    USGS Publications Warehouse

    Knutson, Randy L.; Kwilosz, John R.; Grundel, Ralph

    1999-01-01

    We conducted a three-year mark-release-recapture study of the endangered Karner blue butterfly (Lycaeides melissa samuelis Nabokov) at Indiana Dunes National Lakeshore to describe the butterfly's movement patterns and to assess seasonal changes in the Karner blue's population structure. Estimated mean Karner blue adult life span was less than 3.5 days. Populations exhibited protandry and about a 2:1 male:female sex ratio at population peak within a brood. Ranges, or maximum distances moved by individual butterflies, were typically less than 100 m. Maximum ranges were less than 1 km. These distances are similar to those reported for other lycaenid butterflies and from other studies of the Karner blue in the midwestern United States. At two sites, fewer than 2% of adults had ranges greater than 300 m, while at a third site 4.3% of adults had ranges greater than 300 m. Given typical subpopulation sizes these movement percentages suggest that few adults per generation will move between subpopulations separated by more than 300 m. Movement of individuals between subpopulation sites is important for maintaining genetic diversity within a metapopulation and for recolonizing areas following local extinctions. Therefore, prudent conservation planning should aim for a landscape with habitat patches suitable for Karner blue butterfly occupancy separated by less than 300 m.

  3. Where Do Livestock Guardian Dogs Go? Movement Patterns of Free-Ranging Maremma Sheepdogs

    PubMed Central

    van Bommel, Linda; Johnson, Chris N.

    2014-01-01

    In many parts of the world, livestock guardian dogs (LGDs) are a relatively new and increasingly popular method for controlling the impact of wild predators on livestock. On large grazing properties in Australia, LGDs are often allowed to range freely over large areas, with minimal supervision by their owners. How they behave in this situation is mostly unknown. We fitted free-ranging Maremma sheepdogs with GPS tracking collars on three properties in Victoria, Australia; on two properties, four sheep were also fitted with GPS collars. We investigated how much time the Maremmas spent with their livestock, how far they moved outside the ranges of their stock, and tested whether they use their ranges sequentially, which is an effective way of maintaining a presence over a large area. The 95% kernel isopleth of the Maremmas ranged between 31 and 1161 ha, the 50% kernel isopleth ranged between 4 and 252 ha. Maremmas spent on average 90% of their time in sheep paddocks. Movements away from sheep occurred mostly at night, and were characterised by high-speed travel on relatively straight paths, similar to the change in activity at the edge of their range. Maremmas used different parts of their range sequentially, similar to sheep, and had a distinct early morning and late afternoon peak in activity. Our results show that while free-ranging LGDs spend the majority of their time with livestock, movements away from stock do occur. These movements could be important in allowing the dogs to maintain large territories, and could increase the effectiveness of livestock protection. Allowing LGDs to range freely can therefore be a useful management decision, but property size has to be large enough to accommodate the large areas that the dogs use. PMID:25353319

  4. Individual variation in ontogenetic niche shifts in habitat use and movement patterns of a large estuarine predator (Carcharhinus leucas).

    PubMed

    Matich, Philip; Heithaus, Michael R

    2015-06-01

    Ontogenetic niche shifts are common among animals, yet most studies only investigate niche shifts at the population level, which may overlook considerable differences among individuals in the timing and dynamics of these shifts. Such divergent behaviors within size-/age-classes have important implications for the roles a population-and specific age-classes-play in their respective ecosystem(s). Using acoustic telemetry, we tracked the movements of juvenile bull sharks in the Shark River Estuary of Everglades National Park, Florida, and found that sharks increased their use of marine microhabitats with age to take advantage of more abundant resources, but continued to use freshwater and estuarine microhabitats as refuges from marine predators. Within this population-level ontogenetic niche shift, however, movement patterns varied among individual sharks, with 47 % of sharks exhibiting condition-dependent habitat use and 53 % appearing risk-averse regardless of body condition. Among sharks older than age 0, fifty percent made regular movements between adjacent regions of the estuary, while the other half made less predictable movements that often featured long-term residence in specific regions. Individual differences were apparently shaped by both intrinsic and extrinsic factors, including individual responses to food-risk trade-offs and body condition. These differences appear to develop early in the lives of bull sharks, and persist throughout their residencies in nursery habitats. The widespread occurrence of intraspecific variation in behavior among mobile taxa suggests it is important in shaping population dynamics of at least some species, and elucidating the contexts and timing in which it develops and persists is important for understanding its role within communities. PMID:25669454

  5. Individual variation in ontogenetic niche shifts in habitat use and movement patterns of a large estuarine predator (Carcharhinus leucas).

    PubMed

    Matich, Philip; Heithaus, Michael R

    2015-06-01

    Ontogenetic niche shifts are common among animals, yet most studies only investigate niche shifts at the population level, which may overlook considerable differences among individuals in the timing and dynamics of these shifts. Such divergent behaviors within size-/age-classes have important implications for the roles a population-and specific age-classes-play in their respective ecosystem(s). Using acoustic telemetry, we tracked the movements of juvenile bull sharks in the Shark River Estuary of Everglades National Park, Florida, and found that sharks increased their use of marine microhabitats with age to take advantage of more abundant resources, but continued to use freshwater and estuarine microhabitats as refuges from marine predators. Within this population-level ontogenetic niche shift, however, movement patterns varied among individual sharks, with 47 % of sharks exhibiting condition-dependent habitat use and 53 % appearing risk-averse regardless of body condition. Among sharks older than age 0, fifty percent made regular movements between adjacent regions of the estuary, while the other half made less predictable movements that often featured long-term residence in specific regions. Individual differences were apparently shaped by both intrinsic and extrinsic factors, including individual responses to food-risk trade-offs and body condition. These differences appear to develop early in the lives of bull sharks, and persist throughout their residencies in nursery habitats. The widespread occurrence of intraspecific variation in behavior among mobile taxa suggests it is important in shaping population dynamics of at least some species, and elucidating the contexts and timing in which it develops and persists is important for understanding its role within communities.

  6. [Stereotypic movements].

    PubMed

    Fernández-Alvarez, E

    2003-02-01

    Stereotypic movements are repetitive patterns of movement with certain peculiar features that make them especially interesting. Their physiopathology and their relationship with the neurobehavioural disorders they are frequently associated with are unknown. In this paper our aim is to offer a simple analysis of their dominant characteristics, their differentiation from other processes and a hypothesis of the properties of stereotypic movements, which could all set the foundations for research work into their physiopathology.

  7. Movement patterns of rural and suburban white-tailed deer in Massachusetts

    USGS Publications Warehouse

    Gaughan, C.R.; DeStefano, S.

    2005-01-01

    We used satellite land cover data and the program FRAGSTATS toquantify land cover types and calculate the amount of forest edge available in suburban and rural regions of northeastern and northwestern Massachusetts. Cover categories included forest cover, open canopy vegetation, and non-deer habitat. We calculated all edge segments where forest cover abutted open canopy cover. Our open canopy vegetation category was calculated both with and without low intensity suburban development. We then compared these findings to movement data from 53 (13 males, 40 females) adult radio-marked white-tailed deerOdocoileus virginianusmonitored biweekly and diurnally from January 2001 to January 2003. The range of movements of suburban deer in eastern Massachusetts showed no difference to that of suburban deer in western Massachusetts (P = 0.7). However, the ranges for suburban deer in both eastern and western Massachusetts were 10 times less than those of deer in rural western Massachusetts (P = 0.001).Our findings suggest that landscape configuration, as described by the amount and distribution of edge due to suburban development, which is related to the amount and distribution of resources such as food and cover, affects migratory behavior of white-tailed deer, allowsdeer to have smaller ranges, and contributes to high deer densities.Inclusion of suburban edge in habitat models will increase our understanding of deer-habitat relationships for management of deer in urbanizing environments. ?? 2005 Springer Science + Business Media, Inc.

  8. Residency and movement patterns of Arctic charr Salvelinus alpinus relative to major estuaries.

    PubMed

    Spares, A D; Stokesbury, M J W; Dadswell, M J; O'Dor, R K; Dick, T A

    2015-06-01

    Estuarine residency and marine movements of 43 anadromous Arctic charr Salvelinus alpinus (mean ± s.d. fork length = 523 ± 97 mm) were examined using acoustic tracking in inner Frobisher Bay (IFB; 63° N; 68° W), Canada, from July to September 2008 and 2009. A mean ± s.d. migration duration of 63 ± 7 days occurred from late June to early September. Detected S. alpinus were either continuously (maximum 34 days) or intermittently present in estuarine zones, on average residing approximately one third of time tracked and returning once every 9 days. Significantly higher estuarine residency during the final 15 migration days suggested that a transition phase may occur prior to freshwater re-entry. Low travel rates during flood tide suggested individuals staged before accessing intertidal and estuarine zones. Although the two main estuaries were c. 22 km apart, 19% of tagged individuals used both. Individuals remained relatively close to freshwater overwintering systems, although late-migration inter-estuarine movements may have indicated natal homing. Approximately half of the individuals exhibited extra-estuarine travel, mostly during mid-migration, but remained within 3 km of shore ranging < 30 km straight line distance (SLD) of either estuary. It was concluded that IFB S. alpinus (1) spent a significant portion of their migration within or adjacent to the estuaries and (2) had a restricted marine distribution within 30 km SLD of the river mouths.

  9. Breeding pond selection and movement patterns by eastern spadefoot toads (Scaphiopus holbrookii) in relation to weather and edaphic conditions.

    SciTech Connect

    Cathryn H. Greenberg; George W. Tanner

    2004-08-31

    Cathryn H. Greenberg and George W. Tanner. 2004. Breeding pond selection and movement patterns by eastern spadefoot toads (Scaphiopus holbrookii) in relation to weather and edaphic conditions. J. Herp. 38(4):569-577. Abstract: Eastern Spadefoot Toads (Scaphiopus holbrookii) require fish-free, isolated, ephemeral ponds for breeding but otherwise inhabit the surrounding uplands, commonly xeric longleaf pine (Pinus palustris) wiregrass (Aristida beyrichiana). Hence both pond and upland conditions can potentially affect their breeding biology, and population persistence. Hardwood invasion due to fire suppression in sandhills could alter upland and pond suitability by higher hardwood density and increased transpiration. In this paper we explore breeding and neonatal emigration movements in relation to weather, hydrological conditions of ponds, and surrounding upland matrices. We use 9 years of data from continuous monitoring with drift fences and pitfall traps at 8 ephemeral ponds in 2 upland matrices: regularly-burned, savanna-like sandhills (n = 4), and hardwood-invaded sandhills (n = 4). Neither adult nor neonate captures differed between ponds within the 2 upland matrices, suggesting that they are tolerant of upland heterogeneity created by fire frequency. Explosive breeding occurred during 9 periods and in all seasons; adults were captured rarely otherwise. At a landscape-level rainfall, maximum change in barometric pressure, and an interaction between those 2 variables were significant predictors of explosive breeding. At a pond-level, rainfall, change in pond depth during the month prior to breeding, and days since a pond was last dry were significant predictors of adult captures. Transformation date, rather than weather, was associated with neonatal emigrations, which usually were complete within a week. Movement by first-captured adults and neonates was directional, but adult emigrations were apparently not always toward their origin. Our results suggest that

  10. [Trapped in the body - lived experience and coping of individuals having Parkinson and their relatives with changed movement pattern caused by the disease].

    PubMed

    Kohler, Myrta; Saxer, Susi; Fringer, André; Hantikainen, Virpi

    2014-06-01

    People with Parkinson's disease suffer from various symptoms. Changed movement patterns frequently represent the prevailing symptom experience and influence the everyday life of the affected persons and their relatives. This qualitative study explores how persons with Parkinson's disease and their relatives experience the changed movement patterns and how they manage the consequential problems in their daily life. Eight persons with Parkinson's disease and six partners were interviewed. The interviews were analysed by means of content analysis according to Mayring. The qualitative analysis resulted in two main categories: "effects on the changed movement patterns on everyday life" and "coping skills for dealing with changed movement patterns". The experience of the affected person can be characterised by "being trapped in the body" as well as by a constantly slowing down daily life. The coping strategies are diverse, but all respondents seek to maintain mobility. Partners naturally support the affected persons and take over many tasks. This is associated with elevated distress and the feeling of having to be permanently present. Various coping strategies have to be promoted and included in daily care for people with Parkinson's disease. Consideration of the individual experience of the changed movement patterns is very important in the development of strategies and also the support of the affected persons and relatives that they can keep up with their movements.

  11. Migration patterns, use of stopover areas, and austral summer movements of swainson's hawks

    USGS Publications Warehouse

    Kochert, M.N.; Fuller, M.R.; Schueck, L.S.; Bond, L.; Bechard, M.J.; Woodbridge, B.; Holroyd, G.L.; Martell, M.S.; Banasch, U.

    2011-01-01

    From 1995 to 1998, we tracked movements of adult Swainson's Hawks (Buteo swainsoni), using satellite telemetry to characterize migration, important stopover areas, and movements in the austral summer. We tagged 46 hawks from July to September on their nesting grounds in seven U.S. states and two Canadian provinces. Swainson's Hawks followed three basic routes south on a broad front, converged along the east coast of central Mexico, and followed a concentrated corridor to a communal area in central Argentina for the austral summer. North of 20?? N, southward and northward tracks differed little for individuals from east of the continental divide but differed greatly (up to 1700 km) for individuals from west of the continental divide. Hawks left the breeding grounds mid-August to mid-October; departure dates did not differ by location, year, or sex. Southbound migration lasted 42 to 98 days, northbound migration 51 to 82 days. Southbound, 36% of the Swainson's Hawks departed the nesting grounds nearly 3 weeks earlier than the other radio-marked hawks and made stopovers 9.0-26.0 days long in seven separate areas, mainly in the southern Great Plains, southern Arizona and New Mexico, and northcentral Mexico. The birds stayed in their nonbreeding range for 76 to 128 days. All used a core area in central Argentina within 23% of the 738 800-km2 austral summer range, where they frequently moved long distances (up to 1600 km). Conservation of Swainson's Hawks must be an international effort that considers habitats used during nesting and non-nesting seasons, including migration stopovers. Copyright ?? The Cooper Ornithological Society 2011.

  12. Migration patterns, use of stopover areas, and austral summer movements of Swainson's hawks

    USGS Publications Warehouse

    Kocher, Michael N.; Fuller, Mark R.; Schueck, Linda S.; Bond, Laura; Bechard, Marc J.; Woodbridge, Brian; Holroyd, Geoff L.; Martell, Mark S.; Banasch, Ursula

    2011-01-01

    from 1995 to 1998, we tracked movements of adult Swainson's Hawks (Buteo swainsoni), using satellite telemetry to characterize migration, important stopover areas, and movements in the austral summer. we tagged 46 hawks from July to September on their nesting grounds in seven U.S. states and two Canadian provinces. Swainson's Hawks followed three basic routes south on a broad front, converged along the east coast of cen-tral Mexico, and followed a concentrated corridor to a communal area in central Argentina for the austral summer. North of 20° N, southward and northward tracks differed little for individuals from east of the continental divide but differed greatly (up to 1700 km) for individuals from west of the continental divide. Hawks left the breeding grounds mid-August to mid-October; departure dates did not differ by location, year, or sex. Southbound migra-tion lasted 42 to 98 days, northbound migration 51 to 82 days. Southbound, 36% of the Swainson's Hawks departed the nesting grounds nearly 3 weeks earlier than the other radio-marked hawks and made stopovers 9.0–26.0 days long in seven separate areas, mainly in the southern great Plains, southern Arizona and New Mexico, and north-central Mexico. The birds stayed in their nonbreeding range for 76 to 128 days. All used a core area in central Ar-gentina within 23% of the 738 800-km2 austral summer range, where they frequently moved long distances (up to 1600 km). Conservation of Swainson's Hawks must be an international effort that considers habitats used during nesting and non-nesting seasons, including migration stopovers.

  13. MIGRATION PATTERNS, USE OF STOPOVER AREAS, AND AUSTRAL SUMMER MOVEMENTS OF SWAINSON’S HAWKS

    PubMed Central

    Kochert, Michael N.; Fuller, Mark R.; Schueck, Linda S.; Bond, Laura; Bechard, Marc J.; Woodbridge, Brian; Holroyd, Geoff; Martell, Mark; Banasch, Ursula

    2015-01-01

    From 1995–1998, we tracked movements of adult Swainson’s Hawks (Buteo swainsoni) using satellite telemetry to characterize migration, important stopover areas, and austral summer movements. We tagged 46 hawks from July - September on their nesting grounds in seven U.S. states and two Canadian provinces. Swainson’s Hawks basically followed three routes south on a broad front, converged along the east coast of central Mexico, and followed a concentrated corridor to a communal austral summer area in central Argentina. North of 20° N, southward and northward tracks differed little for individuals from east of the Continental Divide but differed greatly (up to 1700 km) for individuals from west of the Continental Divide. Hawks left the breeding grounds mid-August to mid-October; departure dates did not differ by location, year, or sex. South migration lasted 42 to 98 days, and north migration took 51 to 82 days. On south migration, 36% of the Swainson’s Hawks departed the nesting grounds nearly 3 weeks earlier than the other radio marked hawks and made stopovers 9.0 – 26.0 days long in seven separate areas, mainly in the southern Great Plains, southern Arizona and New Mexico, and north-central Mexico. The austral period lasted 76 to 128 days. All Swainson’s Hawks used a core area in central Argentina within 23% of the 738800 km2 austral summer range where they frequently moved long distances (up to 1600 km). Conservation of Swainson’s Hawks must be an international effort that considers habitats used during nesting and non-nesting seasons including migration stopovers. PMID:26380528

  14. Allowing Learners to Choose: Self-Controlled Practice Schedules for Learning Multiple Movement Patterns

    ERIC Educational Resources Information Center

    Wu, Will F. W.; Magill, Richard A.

    2011-01-01

    For this study, we investigated the effects of self-controlled practice on learning multiple motor skills. Thirty participants were randomly assigned to self-control or yoked conditions. Participants learned a three-keystroke pattern with three different relative time structures. Those in the self-control group chose one of three relative time…

  15. DNA methylation patterns in tissues from mid-gestation bovine foetuses produced by somatic cell nuclear transfer show subtle abnormalities in nuclear reprogramming

    PubMed Central

    2010-01-01

    Background Cloning of cattle by somatic cell nuclear transfer (SCNT) is associated with a high incidence of pregnancy failure characterized by abnormal placental and foetal development. These abnormalities are thought to be due, in part, to incomplete re-setting of the epigenetic state of DNA in the donor somatic cell nucleus to a state that is capable of driving embryonic and foetal development to completion. Here, we tested the hypothesis that DNA methylation patterns were not appropriately established during nuclear reprogramming following SCNT. A panel of imprinted, non-imprinted genes and satellite repeat sequences was examined in tissues collected from viable and failing mid-gestation SCNT foetuses and compared with similar tissues from gestation-matched normal foetuses generated by artificial insemination (AI). Results Most of the genomic regions examined in tissues from viable and failing SCNT foetuses had DNA methylation patterns similar to those in comparable tissues from AI controls. However, statistically significant differences were found between SCNT and AI at specific CpG sites in some regions of the genome, particularly those associated with SNRPN and KCNQ1OT1, which tended to be hypomethylated in SCNT tissues. There was a high degree of variation between individuals in methylation levels at almost every CpG site in these two regions, even in AI controls. In other genomic regions, methylation levels at specific CpG sites were tightly controlled with little variation between individuals. Only one site (HAND1) showed a tissue-specific pattern of DNA methylation. Overall, DNA methylation patterns in tissues of failing foetuses were similar to apparently viable SCNT foetuses, although there were individuals showing extreme deviant patterns. Conclusion These results show that SCNT foetuses that had developed to mid-gestation had largely undergone nuclear reprogramming and that the epigenetic signature at this stage was not a good predictor of whether the

  16. Loading patterns and jaw movements during mastication in Macaca fascicularis: a bone-strain, electromyographic, and cineradiographic analysis.

    PubMed

    Hylander, W L; Johnson, K R; Crompton, A W

    1987-03-01

    Rosette strain gage, electromyography (EMG), and cineradiographic techniques were used to analyze loading patterns and jaw movements during mastication in Macaca fascicularis. The cineradiographic data indicate that macaques generally swallow frequently throughout a chewing sequence, and these swallows are intercalated into a chewing cycle towards the end of a power stroke. The bone strain and jaw movement data indicate that during vigorous mastication the transition between fast close and the power stroke is correlated with a sharp increase in masticatory force, and they also show that in most instances the jaws of macaques are maximally loaded prior to maximum intercuspation, i.e. during phase I (buccal phase) occlusal movements. Moreover, these data indicate that loads during phase II (lingual phase) occlusal movements are ordinarily relatively small. The bone strain data also suggest that the duration of unloading of the jaw during the power stroke of mastication is largely a function of the relaxation time of the jaw adductors. This interpretation is based on the finding that the duration from 100% peak strain to 50% peak strain during unloading closely approximates the half-relaxation time of whole adductor jaw muscles of macaques. The EMG data of the masseter and medial pterygoid muscles have important implications for understanding both the biomechanics of the power stroke and the external forces responsible for the "wishboning" effect that takes place along the mandibular symphysis and corpus during the power stroke of mastication. Although both medial pterygoid muscles reach maximum EMG activity during the power stroke, the activity of the working-side medial pterygoid peaks after the balancing-side medial pterygoid. Associated with the simultaneous increase of force of the working-side medial pterygoid and the decrease of force of the balancing-side medial pterygoid is the persistently high level of EMG activity of the balancing-side deep masseter

  17. The ontogeny of feeding kinematics in a giant salamander Cryptobranchus alleganiensis: Does current function or phylogenetic relatedness predict the scaling patterns of movement?

    PubMed

    Deban, Stephen M; O'Reilly, James C

    2005-01-01

    Studies of the scaling of feeding movements in vertebrates have included three species that display both near-geometric growth and isometry of kinematic variables. These scaling characteristics allow one to examine the "pure" relationship of growth and movement. Despite similar growth patterns, the feeding movements of toads (Bufo) slow down more with increasing body size than those of bass (Micropterus), and sharks (Ginglymostoma). This variation might be due to major differences in the mechanism of prey capture; the bass and sharks use suction to capture prey in water, while the toad uses tongue prehension to capture prey on land. To investigate whether or not these different scaling patterns are correlated with differences in feeding mechanics, we examined the ontogenetic scaling of prey capture movements in the hellbender salamander (Cryptobranchus alleganiensis), which also has near-geometric growth. The hellbender suction feeds in the same general manner as the teleosts and shark, but is much more closely related to the toad. The feeding movements of the hellbender scale more similarly to the feeding movements of toads than to those of fishes or sharks, indicating that phylogenetic relatedness rather than biomechanical similarity predicts ontogenetic scaling patterns of movement. PMID:16351963

  18. Pattern Formation in Populations with Density-Dependent Movement and Two Interaction Scales

    PubMed Central

    Martínez-García, Ricardo; Murgui, Clara; Hernández-García, Emilio; López, Cristóbal

    2015-01-01

    We study the spatial patterns formed by a system of interacting particles where the mobility of any individual is determined by the population crowding at two different spatial scales. In this way we model the behavior of some biological organisms (like mussels) that tend to cluster at short ranges as a defensive strategy, and strongly disperse if there is a high population pressure at large ranges for optimizing foraging. We perform stochastic simulations of a particle-level model of the system, and derive and analyze a continuous density description (a nonlinear diffusion equation). In both cases we show that this interplay of scale-dependent-behaviors gives rise to a rich formation of spatial patterns ranging from labyrinths to periodic cluster arrangements. In most cases these clusters have the very peculiar appearance of ring-like structures, i.e., organisms arranging in the perimeter of the clusters, which we discuss in detail. PMID:26147351

  19. Movement patterns and trajectories of ovigerous blue crabs Callinectes sapidus during the spawning migration

    NASA Astrophysics Data System (ADS)

    Carr, Sarah D.; Tankersley, Richard A.; Hench, James L.; Forward, Richard B.; Luettich, Richard A.

    2004-08-01

    Female blue crabs ( Callinectes sapidus Rathbun) migrate from low salinity estuarine regions to high salinity regions near the ocean to release larvae. During this migration, ovigerous females use ebb-tide transport, a vertical migratory behavior in which they ascend into the water column during ebb tides, to move seaward to larval release areas. In order to determine the relationship of ebb-tide vertical migrations to local currents and the influence of these vertical migrations on the horizontal transport of blue crabs in the estuary, ovigerous females with mature embryos (˜1-3 days from hatching) were tracked near Beaufort Inlet, North Carolina (USA), in July and August 2001 and 2002. Crabs were tagged and tracked using ultrasonic telemetry, and currents near the crabs were measured simultaneously with a shipboard acoustic Doppler current profiler. During the two seasons, eight crabs were successfully tracked for periods ranging from 3.9-37.0 h and for distances ranging from 1.9-10.6 km. All crabs migrated seaward during the tracking periods. Crabs moved episodically during all tidal phases with periods of movement on the order of minutes to an hour. They moved with local currents in terms of both speed and direction during ebb tides, consistent with ebb-tide transport, and moved down-estuary (seaward) in opposition to local currents during flood tides. The percentage of time that crabs were active was higher during night ebb tides than during day ebb tides or flood tides and increased with increasing ebb-tide current speed. Mean migratory speeds were 0.11, 0.04, 0.08 and 0.02 m s -1 during night ebb, night flood, day ebb and day flood tides, respectively, and net migratory speeds were on the order of 5 km day -1. Due to the episodic nature of the crabs' movements, the total distances that crabs traveled during ebb tides ranged from 10-40% of the distances that passive particles could have traveled under the same conditions.

  20. Movement patterns and the conservation of amphibians breeding in small, temporary wetlands

    USGS Publications Warehouse

    Dodd, C.K.; Cade, B.S.

    1998-01-01

    Many amphibians breed in water but live most of their lives in terrestrial habitats. Little is known, however, about the spatial distribution of these habitats or of the distances and directions amphibians move to reach breeding sites. The amphibian community at a small, temporary pond in northcentral Florida was monitored for 5 years. Based on captures and recaptures of more than 2500 striped newts (Notophthalmus perstriatus) and 5700 eastern narrow-mouthed toads (Gastrophryne carolinensis), we tabulated the angles of orientation that these amphibians entered and exited the pond basin. Our results showed that movements of these species between the pond and terrestrial habitats were nonrandom in orientation, but that narrow corridors did not appear to be used. Differences between the species likely reflect differences in habitat preferences, whereas intraspecific differences among years and between the sexes likely reflect variation among individuals. For terrestrial buffer zones to be effective at conserving pond-breeding amphibian communities, they need both a distance and a directional component. The determination of a directional component may be obscured if studies are carried out over a short time span. Conservation efforts for wetland-breeding amphibians that concentrate solely on the wetland likely will fail without consideration of the adjacent terrestrial habitat.

  1. Movement patterns in leiopelmatid frogs: Insights into the locomotor repertoire of basal anurans.

    PubMed

    Reilly, Stephen; Essner, Richard; Wren, Sally; Easton, Luke; Bishop, Phillip J

    2015-12-01

    Movements and locomotor behaviour were studied in the most basal living frog family (Leiopelmatidae: Ascaphus+Leiopelmatidae), which includes two stream-dwelling species and several that have transitioned into terrestrial niches. These cryptic frogs remain immobile over 99.6% of the time above ground as they sit in wait of prey and only rarely use jumping to escape. Walking is their primary mode of locomotion. The two stream species, which are separated by deep time and extreme geographic distance, have nearly identical behavioural repertoires and locomotor performance, which included occasional jumping as a means to change foraging positions. The terrestrial species, one of which has become semi-arboreal, rarely jump in nature and rely on chemical and postural antipredator behaviours to avoid predation. If early frogs resembled leiopelmatids, they were not well versed in jumping. Locomotor behaviour and performance of leiopelmatid frogs do not support the hypothesis that frog jumping originally evolved primarily as a means to rapidly escape into water. Given the basal position of the leiopelmatids, the locomotor strategy of these cryptic, cold-adapted, belly-flopping anurans that usually walk may represent a successful initial step in the evolution of saltatorial locomotion in frogs.

  2. Eye movements reveal distinct encoding patterns for number and cumulative surface area in random dot arrays

    PubMed Central

    Odic, Darko; Halberda, Justin

    2015-01-01

    Humans can quickly and intuitively represent the number of objects in a scene using visual evidence through the Approximate Number System (ANS). But the computations that support the encoding of visual number—the transformation from the retinal input into ANS representations—remain controversial. Two types of number encoding theories have been proposed: those arguing that number is encoded through a dedicated, enumeration computation, and those arguing that visual number is inferred from nonnumber specific visual features, such as surface area, density, convex hull, etc. Here, we attempt to adjudicate between these two theories by testing participants on both a number and a cumulative area task while also tracking their eye-movements. We hypothesize that if approximate number and surface area depend on distinct encoding computations, saccadic signatures should be distinct for the two tasks, even if the visual stimuli are identical. Consistent with this hypothesis, we find that discriminating number versus cumulative area modulates both where participants look (i.e., participants spend more time looking at the more numerous set in the number task and the larger set in the cumulative area task), and how participants look (i.e., cumulative area encoding shows fewer, longer saccades, while number encoding shows many short saccades and many switches between targets). We further identify several saccadic signatures that are associated with task difficulty and correct versus incorrect trials for both dimensions. These results suggest distinct encoding algorithms for number and cumulative area extraction, and thereby distinct representations of these dimensions. PMID:26575191

  3. Seasonal Movement Patterns and Long-Range Dispersal of Asian Citrus Psyllid in Florida Citrus.

    PubMed

    Lewis-Rosenblum, Hannah; Martini, Xavier; Tiwari, Siddharth; Stelinski, Lukasz L

    2015-02-01

    The Asian citrus psyllid, Diaphorina citri Kuwayama, is the vector of the bacterial pathogen, Candidatus Liberibacter asiaticus, which is the causal agent of huanglongbing (HLB) in the United States. Both short-range and long-range dispersal of D. citri adults affect the spread of HLB; however, little is known about the long-range dispersal capabilities of D. citri in the field or the seasonality of flight behavior. In the present study, an in situ protein marking technique was used to determine the dispersal of D. citri by trapping marked adults under natural field conditions. D. citri movement from abandoned citrus groves to adjacent managed citrus groves was greatest during the spring and summer months and decreased significantly during the colder months (September-March). D. citri were able to traverse potential geographic barriers such as roads and fallow fields. In an experiment conducted to determine long-range dispersal capacity in the absence of severe weather events, D. citri were able to disperse at least 2 km within 12 d. Wind direction was not correlated with the number of marked psyllids captured, indicating substantial flight capability by D. citri. Finally, the number of marked psyllids captured increased with the density of emerging young leaves on surrounding trees. The results confirm that abandoned citrus groves in Florida serve as reservoirs for D. citri, which can disperse across long distances despite geographical barriers. PMID:26470097

  4. Seasonal Movement Patterns and Long-Range Dispersal of Asian Citrus Psyllid in Florida Citrus.

    PubMed

    Lewis-Rosenblum, Hannah; Martini, Xavier; Tiwari, Siddharth; Stelinski, Lukasz L

    2015-02-01

    The Asian citrus psyllid, Diaphorina citri Kuwayama, is the vector of the bacterial pathogen, Candidatus Liberibacter asiaticus, which is the causal agent of huanglongbing (HLB) in the United States. Both short-range and long-range dispersal of D. citri adults affect the spread of HLB; however, little is known about the long-range dispersal capabilities of D. citri in the field or the seasonality of flight behavior. In the present study, an in situ protein marking technique was used to determine the dispersal of D. citri by trapping marked adults under natural field conditions. D. citri movement from abandoned citrus groves to adjacent managed citrus groves was greatest during the spring and summer months and decreased significantly during the colder months (September-March). D. citri were able to traverse potential geographic barriers such as roads and fallow fields. In an experiment conducted to determine long-range dispersal capacity in the absence of severe weather events, D. citri were able to disperse at least 2 km within 12 d. Wind direction was not correlated with the number of marked psyllids captured, indicating substantial flight capability by D. citri. Finally, the number of marked psyllids captured increased with the density of emerging young leaves on surrounding trees. The results confirm that abandoned citrus groves in Florida serve as reservoirs for D. citri, which can disperse across long distances despite geographical barriers.

  5. Movement patterns in leiopelmatid frogs: Insights into the locomotor repertoire of basal anurans.

    PubMed

    Reilly, Stephen; Essner, Richard; Wren, Sally; Easton, Luke; Bishop, Phillip J

    2015-12-01

    Movements and locomotor behaviour were studied in the most basal living frog family (Leiopelmatidae: Ascaphus+Leiopelmatidae), which includes two stream-dwelling species and several that have transitioned into terrestrial niches. These cryptic frogs remain immobile over 99.6% of the time above ground as they sit in wait of prey and only rarely use jumping to escape. Walking is their primary mode of locomotion. The two stream species, which are separated by deep time and extreme geographic distance, have nearly identical behavioural repertoires and locomotor performance, which included occasional jumping as a means to change foraging positions. The terrestrial species, one of which has become semi-arboreal, rarely jump in nature and rely on chemical and postural antipredator behaviours to avoid predation. If early frogs resembled leiopelmatids, they were not well versed in jumping. Locomotor behaviour and performance of leiopelmatid frogs do not support the hypothesis that frog jumping originally evolved primarily as a means to rapidly escape into water. Given the basal position of the leiopelmatids, the locomotor strategy of these cryptic, cold-adapted, belly-flopping anurans that usually walk may represent a successful initial step in the evolution of saltatorial locomotion in frogs. PMID:26449314

  6. Supplemental Feeding for Ecotourism Reverses Diel Activity and Alters Movement Patterns and Spatial Distribution of the Southern Stingray, Dasyatis americana

    PubMed Central

    Corcoran, Mark J.; Wetherbee, Bradley M.; Shivji, Mahmood S.; Potenski, Matthew D.; Chapman, Demian D.; Harvey, Guy M.

    2013-01-01

    Southern stingrays, Dasyatis americana, have been provided supplemental food in ecotourism operations at Stingray City Sandbar (SCS), Grand Cayman since 1986, with this site becoming one of the world’s most famous and heavily visited marine wildlife interaction venues. Given expansion of marine wildlife interactive tourism worldwide, there are questions about the effects of such activities on the focal species and their ecosystems. We used a combination of acoustic telemetry and tag-recapture efforts to test the hypothesis that human-sourced supplemental feeding has altered stingray activity patterns and habitat use at SCS relative to wild animals at control sites. Secondarily, we also qualitatively estimated the population size of stingrays supporting this major ecotourism venue. Tag-recapture data indicated that a population of at least 164 stingrays, over 80% female, utilized the small area at SCS for prolonged periods of time. Examination of comparative movements of mature female stingrays at SCS and control sites revealed strong differences between the two groups: The fed animals demonstrated a notable inversion of diel activity, being constantly active during the day with little movement at night compared to the nocturnally active wild stingrays; The fed stingrays utilized significantly (p<0.05) smaller 24 hour activity spaces compared to wild conspecifics, staying in close proximity to the ecotourism site; Fed stingrays showed a high degree of overlap in their core activity spaces compared to wild stingrays which were largely solitary in the spaces utilized (72% vs. 3% overlap respectively). Supplemental feeding has strikingly altered movement behavior and spatial distribution of the stingrays, and generated an atypically high density of animals at SCS which could have downstream fitness costs for individuals and potentially broader ecosystem effects. These findings should help environmental managers plan mitigating measures for existing operations, and

  7. Movement patterns of Bar-headed Geese Anser indicus during breeding and post-breeding periods at Qinghai Lake, China

    USGS Publications Warehouse

    Cui, P.; Hou, Y.; Tang, M.; Zhang, H.; Zhou, Y.; Yin, Z.; Li, T.; Guo, S.; Xing, Z.; He, Y.; Prosser, D.J.; Newman, S.H.; Takekawa, J.Y.; Yan, B.; Lei, F.

    2011-01-01

    The highly pathogenic avian influenza (HPAI) H5N1 outbreak at Qinghai Lake, China, in 2005 caused the death of over 6,000 migratory birds, half of which were Bar-headed Geese Anser indicus. Understanding the movements of this species may inform monitoring of outbreak risks for HPAI viruses; thus, we investigated the movement patterns of 29 Bar-headed Geese at Qinghai Lake, China during 2007 and 2008 by using high resolution GPS satellite telemetry. We described the movements and distribution of marked Bar-headed Geese during the pre-nesting, nesting, and moulting periods. Of 21 Bar-headed Geese with complete transmission records, 3 moved to other areas during the nesting period: 2 to Jianghe wetland (50 km northwest of Qinghai Lake) and 1 to Cuolongka Lake (220 km northwest of Qinghai Lake) during the nesting period. We identified nesting attempts of 7 of the marked geese at Qinghai Lake. Four completed successful nesting attempts according to our rules of judgment for the breeding status, and 2 geese lost broods soon after hatching (hereafter referred to as unsuccessful breeders). Of 18 geese present at Qinghai Lake during the nesting period, 9 (6 non-breeders, 2 successful breeders and 1 unsuccessful breeder) remained at Qinghai Lake during the moulting period; and 9 (5 non-breeders, 4 unsuccessful breeders) left Qinghai Lake for moulting. Kuhai Lake, Donggeicuona Lake, Alake Lake, Zhaling-Eling Lake area and Huangheyuan wetland area were used as moulting sites. Geese that moulted at Qinghai Lake, Cuolongka Lake, Kuhai Lake, Donggeicuona Lake and Alake Lake also moved to Zhaling-Eling Lake area or Huangheyuan wetland area and stayed there for several days prior to autumn migration. Mean home range and core area estimates did not differ significantly by sex, year and between breeders and non-breeders. ?? 2010 Dt. Ornithologen-Gesellschaft e.V.

  8. Movement patterns of Bar-headed Geese Anser indicus during breeding and post-breeding periods at Qinghai Lake, China

    USGS Publications Warehouse

    Cui, Peng; Hou, Yuansheng; Tang, Mingjie; Zhang, Haiting; Zuohua, Yuanchun; Yin, Zuohua; Li, Tianxian; Guo, Shan; Xing, Zhi; He, Yubang; Prosser, Diann J.; Newman, Scott H.; Takekawa, John Y.; Yan, Baoping; Lei, Fumin

    2011-01-01

    The highly pathogenic avian influenza (HPAI) H5N1 outbreak at Qinghai Lake, China, in 2005 caused the death of over 6,000 migratory birds, half of which were Bar-headed Geese Anser indicus. Understanding the movements of this species may inform monitoring of outbreak risks for HPAI viruses; thus, we investigated the movement patterns of 29 Bar-headed Geese at Qinghai Lake, China during 2007 and 2008 by using high resolution GPS satellite telemetry. We described the movements and distribution of marked Bar-headed Geese during the pre-nesting, nesting, and moulting periods. Of 21 Bar-headed Geese with complete transmission records, 3 moved to other areas during the nesting period: 2 to Jianghe wetland (50 km northwest of Qinghai Lake) and 1 to Cuolongka Lake (220 km northwest of Qinghai Lake) during the nesting period. We identified nesting attempts of 7 of the marked geese at Qinghai Lake. Four completed successful nesting attempts according to our rules of judgment for the breeding status, and 2 geese lost broods soon after hatching (hereafter referred to as unsuccessful breeders). Of 18 geese present at Qinghai Lake during the nesting period, 9 (6 non-breeders, 2 successful breeders and 1 unsuccessful breeder) remained at Qinghai Lake during the moulting period; and 9 (5 non-breeders, 4 unsuccessful breeders) left Qinghai Lake for moulting. Kuhai Lake, Donggeicuona Lake, Alake Lake, Zhaling-Eling Lake area and Huangheyuan wetland area were used as moulting sites. Geese that moulted at Qinghai Lake, Cuolongka Lake, Kuhai Lake, Donggeicuona Lake and Alake Lake also moved to Zhaling-Eling Lake area or Huangheyuan wetland area and stayed there for several days prior to autumn migration. Mean home range and core area estimates did not differ significantly by sex, year and between breeders and non-breeders.

  9. Supplemental feeding for ecotourism reverses diel activity and alters movement patterns and spatial distribution of the southern stingray, Dasyatis americana.

    PubMed

    Corcoran, Mark J; Wetherbee, Bradley M; Shivji, Mahmood S; Potenski, Matthew D; Chapman, Demian D; Harvey, Guy M

    2013-01-01

    Southern stingrays, Dasyatis americana, have been provided supplemental food in ecotourism operations at Stingray City Sandbar (SCS), Grand Cayman since 1986, with this site becoming one of the world's most famous and heavily visited marine wildlife interaction venues. Given expansion of marine wildlife interactive tourism worldwide, there are questions about the effects of such activities on the focal species and their ecosystems. We used a combination of acoustic telemetry and tag-recapture efforts to test the hypothesis that human-sourced supplemental feeding has altered stingray activity patterns and habitat use at SCS relative to wild animals at control sites. Secondarily, we also qualitatively estimated the population size of stingrays supporting this major ecotourism venue. Tag-recapture data indicated that a population of at least 164 stingrays, over 80% female, utilized the small area at SCS for prolonged periods of time. Examination of comparative movements of mature female stingrays at SCS and control sites revealed strong differences between the two groups: The fed animals demonstrated a notable inversion of diel activity, being constantly active during the day with little movement at night compared to the nocturnally active wild stingrays; The fed stingrays utilized significantly (p<0.05) smaller 24 hour activity spaces compared to wild conspecifics, staying in close proximity to the ecotourism site; Fed stingrays showed a high degree of overlap in their core activity spaces compared to wild stingrays which were largely solitary in the spaces utilized (72% vs. 3% overlap respectively). Supplemental feeding has strikingly altered movement behavior and spatial distribution of the stingrays, and generated an atypically high density of animals at SCS which could have downstream fitness costs for individuals and potentially broader ecosystem effects. These findings should help environmental managers plan mitigating measures for existing operations, and

  10. Supplemental feeding for ecotourism reverses diel activity and alters movement patterns and spatial distribution of the southern stingray, Dasyatis americana.

    PubMed

    Corcoran, Mark J; Wetherbee, Bradley M; Shivji, Mahmood S; Potenski, Matthew D; Chapman, Demian D; Harvey, Guy M

    2013-01-01

    Southern stingrays, Dasyatis americana, have been provided supplemental food in ecotourism operations at Stingray City Sandbar (SCS), Grand Cayman since 1986, with this site becoming one of the world's most famous and heavily visited marine wildlife interaction venues. Given expansion of marine wildlife interactive tourism worldwide, there are questions about the effects of such activities on the focal species and their ecosystems. We used a combination of acoustic telemetry and tag-recapture efforts to test the hypothesis that human-sourced supplemental feeding has altered stingray activity patterns and habitat use at SCS relative to wild animals at control sites. Secondarily, we also qualitatively estimated the population size of stingrays supporting this major ecotourism venue. Tag-recapture data indicated that a population of at least 164 stingrays, over 80% female, utilized the small area at SCS for prolonged periods of time. Examination of comparative movements of mature female stingrays at SCS and control sites revealed strong differences between the two groups: The fed animals demonstrated a notable inversion of diel activity, being constantly active during the day with little movement at night compared to the nocturnally active wild stingrays; The fed stingrays utilized significantly (p<0.05) smaller 24 hour activity spaces compared to wild conspecifics, staying in close proximity to the ecotourism site; Fed stingrays showed a high degree of overlap in their core activity spaces compared to wild stingrays which were largely solitary in the spaces utilized (72% vs. 3% overlap respectively). Supplemental feeding has strikingly altered movement behavior and spatial distribution of the stingrays, and generated an atypically high density of animals at SCS which could have downstream fitness costs for individuals and potentially broader ecosystem effects. These findings should help environmental managers plan mitigating measures for existing operations, and

  11. Relations among physical activity patterns, lifestyle activities, and fundamental movement skills for Finnish students in grade 7.

    PubMed

    Jaakkola, Timo; Kalaja, Sami; Liukkonen, Jarmo; Jutila, Ari; Virtanen, Petri; Watt, Anthony

    2009-02-01

    To investigate the relations among leisure time physical activity and in sport clubs, lifestyle activities, and the locomotor, balance manipulative skills of Grade 7 students participating in Finnish physical education at a secondary school in central Finland completed self-report questionnaires on their physical activity patterns at leisure time and during sport club participation, and time spent watching television and using the computer and other electronic media. Locomotor skills were analyzed by the leaping test, balance skills by the flamingo standing test, and manipulative skills by the accuracy throwing test. Analysis indicated physical activity in sport clubs positively explained scores on balance and locomotor tests but not on accuracy of throwing. Leisure time physical activity and lifestyle activities were not statistically significant predictors of performance on any movement skill tests. Girls scored higher on the static balance skill and boys higher on the throwing task. Overall, physical activity in sport clubs was more strongly associated with performance on the fundamental movement tasks than was physical activity during leisure. PMID:19425451

  12. Patterns of spatio-temporal correlations in the neural activity of the cat motor cortex during trained forelimb movements.

    PubMed

    Ghosh, Soumya; Putrino, David; Burro, Bianca; Ring, Alexander

    2009-06-01

    In order to study how neurons in the primary motor cortex (MI) are dynamically linked together during skilled movement, we recorded simultaneously from many cortical neurons in cats trained to perform a reaching and retrieval task using their forelimbs. Analysis of task-related spike activity in the MI of the hemisphere contralateral to the reaching forelimb (in identified forelimb or hindlimb representations) recorded through chronically implanted microwires, was followed by pairwise evaluation of temporally correlated activity in these neurons during task performance using shuffle corrected cross-correlograms. Over many months of recording, a variety of task-related modulations of neural activities were observed in individual efferent zones. Positively correlated activity (mainly narrow peaks at zero or short latencies) was seen during task performance frequently between neurons recorded within the forelimb representation of MI, rarely within the hindlimb area of MI, and never between forelimb and hindlimb areas. Correlated activity was frequently observed between neurons with different patterns of task-related activity or preferential activity during different task elements (reaching, feeding, etc.), and located in efferent zones with dissimilar representation as defined by intracortical microstimulation. The observed synchronization of action potentials among selected but functionally varied groups of MI neurons possibly reflects dynamic recruitment of network connections between efferent zones during skilled movement.

  13. Movement patterns of armado, Pterodoras granulosus, in the Paraná River Basin

    USGS Publications Warehouse

    Makrakis, M.C.; Miranda, L.E.; Makrakis, S.; Fernandez, D.R.; Garcia, J.O.; Dias, J.H.P.

    2007-01-01

    We studied the migratory behaviour of armado, Pterodoras granulosus, in the Paraná River Basin of Brazil, Paraguay and Argentina, during 1997–2005. This species invaded the Upper Paraná River after upstream dispersal was facilitated when Itaipu Reservoir inundated a natural barrier. Fish were tagged (N = 8051) in the mainstems of the Yacyreta and Itaipu reservoirs, bays of major tributaries, the Paraná River floodplain above Itaipu Reservoir, and below dams. In all, 420 fish were recaptured of which 61% moved away from the release area. Fish moved a maximum of 215 km (mean 42), and at a maximum rate of 9.4 km·day−1 (mean 0.6). Of the 256 armados that moved away from the release site, 145 moved upstream towards unimpounded stretches of the Paraná River and 111 moved downstream into the reservoir and bays of its tributaries (maximum 150 km). Based on the observed migratory movements, we suspect that most of the reproductive output originates in tributaries to the reservoirs. The ability of this species to expand its range presents a conundrum by pitting fishery management interests against conservation needs. Maintenance of the important armado fisheries depends on the ability of the species to migrate freely to use spawning and nursery areas in reservoir tributaries and floodplains. However, its ability to migrate long distances can allow this non-native species the opportunity to invade most of the Upper Paraná River.

  14. Space Use and Movement Patterns in a Semi-Free-Ranging Herd of European Bison (Bison bonasus).

    PubMed

    Ramos, Amandine; Petit, Odile; Longour, Patrice; Pasquaretta, Cristian; Sueur, Cédric

    2016-01-01

    The successful reintroduction and restocking of the European Bison demands a reliable knowledge of the biology of this species. Yet little is known to date about the European bison, and empirical data remains insufficient to set up a reliable plan ensuring the reintroduction, maintenance and survival of populations in habitats that have been largely modified by human activity. Studies of the ecology, social behaviour and management of bison are therefore crucial to the conservation of this species and its cohabitation with humans. To meet these challenges, we focused on movement patterns and space use in a semi-free-ranging herd of European bison living in the Réserve Biologique des Monts-d'Azur (France). Bison spend over 80% of their time foraging and resting; foraging mainly occurs around the artificial feeding sites (i.e., hay racks) or in meadows. The time of day and the presence of snow have no influence on the time budget allocated to each activity. Animals, however, spend more time at the food racks in winter. Bison also spend most of their time in small groups of individuals, confirming the occurrence of both fission-fusion dynamics and sexual segregation in this species. Bison seem to follow a Lévy walk pattern of movement, which is probably related to the geographical distribution and size of food patches in the reserve. The conclusions of this study provide a better understanding of the sociality, life habits and habitat use of bison, and also describe how the provision of hay affects all these behaviours. These results could be useful in the development of tools to select the most suitable habitats for the reintroduction, management and conservation of bison populations. PMID:26841107

  15. Space Use and Movement Patterns in a Semi-Free-Ranging Herd of European Bison (Bison bonasus)

    PubMed Central

    Ramos, Amandine; Petit, Odile; Longour, Patrice; Pasquaretta, Cristian; Sueur, Cédric

    2016-01-01

    The successful reintroduction and restocking of the European Bison demands a reliable knowledge of the biology of this species. Yet little is known to date about the European bison, and empirical data remains insufficient to set up a reliable plan ensuring the reintroduction, maintenance and survival of populations in habitats that have been largely modified by human activity. Studies of the ecology, social behaviour and management of bison are therefore crucial to the conservation of this species and its cohabitation with humans. To meet these challenges, we focused on movement patterns and space use in a semi-free-ranging herd of European bison living in the Réserve Biologique des Monts-d’Azur (France). Bison spend over 80% of their time foraging and resting; foraging mainly occurs around the artificial feeding sites (i.e., hay racks) or in meadows. The time of day and the presence of snow have no influence on the time budget allocated to each activity. Animals, however, spend more time at the food racks in winter. Bison also spend most of their time in small groups of individuals, confirming the occurrence of both fission-fusion dynamics and sexual segregation in this species. Bison seem to follow a Lévy walk pattern of movement, which is probably related to the geographical distribution and size of food patches in the reserve. The conclusions of this study provide a better understanding of the sociality, life habits and habitat use of bison, and also describe how the provision of hay affects all these behaviours. These results could be useful in the development of tools to select the most suitable habitats for the reintroduction, management and conservation of bison populations. PMID:26841107

  16. Space Use and Movement Patterns in a Semi-Free-Ranging Herd of European Bison (Bison bonasus).

    PubMed

    Ramos, Amandine; Petit, Odile; Longour, Patrice; Pasquaretta, Cristian; Sueur, Cédric

    2016-01-01

    The successful reintroduction and restocking of the European Bison demands a reliable knowledge of the biology of this species. Yet little is known to date about the European bison, and empirical data remains insufficient to set up a reliable plan ensuring the reintroduction, maintenance and survival of populations in habitats that have been largely modified by human activity. Studies of the ecology, social behaviour and management of bison are therefore crucial to the conservation of this species and its cohabitation with humans. To meet these challenges, we focused on movement patterns and space use in a semi-free-ranging herd of European bison living in the Réserve Biologique des Monts-d'Azur (France). Bison spend over 80% of their time foraging and resting; foraging mainly occurs around the artificial feeding sites (i.e., hay racks) or in meadows. The time of day and the presence of snow have no influence on the time budget allocated to each activity. Animals, however, spend more time at the food racks in winter. Bison also spend most of their time in small groups of individuals, confirming the occurrence of both fission-fusion dynamics and sexual segregation in this species. Bison seem to follow a Lévy walk pattern of movement, which is probably related to the geographical distribution and size of food patches in the reserve. The conclusions of this study provide a better understanding of the sociality, life habits and habitat use of bison, and also describe how the provision of hay affects all these behaviours. These results could be useful in the development of tools to select the most suitable habitats for the reintroduction, management and conservation of bison populations.

  17. Freshwater movement patterns by juvenile Pacific salmon Oncorhynchus spp. before they migrate to the ocean: Oh the places you'll go!

    PubMed

    Shrimpton, J M; Warren, K D; Todd, N L; McRae, C J; Glova, G J; Telmer, K H; Clarke, A D

    2014-10-01

    Juvenile movement patterns for coho salmon Oncorhynchus kisutch and Chinook salmon Oncorhynchus tshawytscha from two large interior rivers of British Columbia, Canada, were examined. Otoliths from post-spawned fishes were collected on spawning grounds and elemental signatures were determined through transects from sectioned otoliths using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS). Large variations in otolith elemental signatures were found during the freshwater life stage indicative of movement downstream to rivers and tributaries that differed in elemental signature. This study highlights that downstream movements occur before migration to the ocean during the parr-smolt transformation. Extensive downstream movements of parr appear to be a successful life-history strategy based on variations observed in the otolith elemental signatures of spawners. Movements downstream in parr and the remarkable homing ability of adults also suggest that imprinting to natal streams must occur prior to the parr-smolt transformation. PMID:25053226

  18. Processing of surface EMG through pattern recognition techniques aimed at classifying shoulder joint movements.

    PubMed

    Rivela, Diletta; Scannella, Alessia; Pavan, Esteban E; Frigo, Carlo A; Belluco, Paolo; Gini, Giuseppina

    2015-01-01

    Artificial arms for shoulder disarticulation need a high number of degrees of freedom to be controlled. In order to control a prosthetic shoulder joint, an intention detection system based on surface electromyography (sEMG) pattern recognition methods was proposed and experimentally investigated. Signals from eight trunk muscles that are generally preserved after shoulder disarticulation were recorded from a group of eight normal subjects in nine shoulder positions. After data segmentation, four different features were extracted (sample entropy, cepstral coefficients of the 4th order, root mean square and waveform length) and classified by means of linear discriminant analysis. The classification accuracy was 92.1% and this performance reached 97.9% after reducing the positions considered to five classes. To reduce the computational cost, the two channels with the least discriminating information were neglected yielding to a classification accuracy diminished by just 4.08%. PMID:26736704

  19. Water movement through blanket peat is dominated by a complicated pattern of near-surface flows

    NASA Astrophysics Data System (ADS)

    Turner, Ed; Baird, Andy; Billett, Mike; Chapman, Pippa; Dinsmore, Kerry; Holden, Joseph

    2015-04-01

    Blanket peatland formation and functioning depend strongly on hydrology. Omitting the potential for pipe flow, the acrotelm-catotelm model is still widely held to apply to blanket peatlands. In the model, water flow through the peat profile is dominated by near-surface flow in the acrotelm, whereas water movement below the level of (near) permanent saturation (the catotelm) is characterised by very low hydraulic conductivity (K). Whilst some work has been done on characterising Kat different depths in blanket peatlands, very little is known about near-surface K, particularly with respect to how it varies between microforms and over fine spatial scales. We undertook a detailed investigation of near-surface (0 - 12 cm) and deeper (30 and 50 cm) K at a blanket peatland site in the Flow Country in Scotland (UK). Near-surface Kof peat samples taken across a range of microforms was measured vertically (Kv) and horizontally (Kh) in the laboratory using a new 'split cylinder' method (n = 48 excluding repeat tests). K30 (n = 20) andK50 (n = 20) were estimated in situ using the piezometer or seepage-tube method. To help our interpretation of the near-surface K measurements we recorded the vegetation cover from where the peat samples were taken and characterised each peat sample in terms of its plant macrofossil assemblage and dry bulk density. We found that Kvand Khwere highly variable between microforms in the near-surface samples, ranging over two orders of magnitude (0.489 - 0.003 cm s-1). Kernel density plots show that Kvwas most commonly in the region of ~0.03 cm s-1 at 0 - 6 cm, and ~0.015 cm s-1 at 6 - 12 cm, whereas Kh was ~0.05 and ~0.001 cm s-1 respectively. These data reveal a high degree of absolute variability and anisotropy in K over small scales. The deeper K30and K50 values were typically an order of magnitude or more lower than the near-surface K, and were less variable between test locations with the exception of poorly humified Sphagnum-dominated peat

  20. Time-based user-movement pattern analysis from location-based social network data

    NASA Astrophysics Data System (ADS)

    Chuan, Huey Ling; Kulkumjon, Isaraporn; Dangi, Surbhi

    2013-01-01

    Virtual social interactions play an increasingly important role in the discovery of places with digital recommendations. Our hypothesis is that people define the character of a city by the type of places they frequent. With a brief description of our dataset, anomalies and observations about the data, this paper delves into three distinct approaches to visualize the dataset addressing our two goals of: 1. Arriving at a time-based region specific recommendation logic for different types of users classified by the places they frequent. 2. Analyzing the behaviors of users that check-in in groups of two or more people. The study revealed that distinct patterns exist for people that are residents of the city and for people who are short-term visitors to the city. The frequency of visits, however, is both dependent on the time of the day as well as the urban area itself (e.g. eateries, offices, local attractions). The observations can be extended for application in food and travel recommendation engines as well as for research in urban analytics, smart cities and town planning.

  1. Patterns of eating and movement that best maintain reduction in overweight.

    PubMed

    Booth, D A; Blair, A J; Lewis, V J; Baek, S H

    2004-12-01

    Two studies of the influences of specific patterns of eating and exercising behaviour on body weight in English Midlands women were re-analysed using correlations as the measure of effect size. As predicted from computational modelling of hunger-sating mechanisms, avoiding energy-containing drinks and foods at the ends of and between meals was the behaviour most influencing year-long weight loss. However, although eating between meals is often called snacking, the term 'snack' appeared to be too ambiguous in this culture for its use in helping efforts to control weight. Avoidance of particular sorts of fat-rich foods was also associated with longer-term weight loss. Attempts at severe restriction of intake at mealtimes were associated with weight loss during a period of intensive dieting, but did not contribute to maintenance of that weight reduction. Using diet formulae to attain rapid weight loss was associated with significant weight gain over a year. These results support the suggestion that the first line of defence against weight gain is avoiding all sources of energy during drink breaks, with personally relevant advice on lower fat versions of particular foods also being important. Continued neglect of the behaviour-specific correlational approach to gaining evidence for less fattening habits does nothing to slow the rise in obesity.

  2. Patterns of eating and movement that best maintain reduction in overweight.

    PubMed

    Booth, D A; Blair, A J; Lewis, V J; Baek, S H

    2004-12-01

    Two studies of the influences of specific patterns of eating and exercising behaviour on body weight in English Midlands women were re-analysed using correlations as the measure of effect size. As predicted from computational modelling of hunger-sating mechanisms, avoiding energy-containing drinks and foods at the ends of and between meals was the behaviour most influencing year-long weight loss. However, although eating between meals is often called snacking, the term 'snack' appeared to be too ambiguous in this culture for its use in helping efforts to control weight. Avoidance of particular sorts of fat-rich foods was also associated with longer-term weight loss. Attempts at severe restriction of intake at mealtimes were associated with weight loss during a period of intensive dieting, but did not contribute to maintenance of that weight reduction. Using diet formulae to attain rapid weight loss was associated with significant weight gain over a year. These results support the suggestion that the first line of defence against weight gain is avoiding all sources of energy during drink breaks, with personally relevant advice on lower fat versions of particular foods also being important. Continued neglect of the behaviour-specific correlational approach to gaining evidence for less fattening habits does nothing to slow the rise in obesity. PMID:15527930

  3. Movement Patterns for a Critically Endangered Species, the Leatherback Turtle (Dermochelys coriacea), Linked to Foraging Success and Population Status

    PubMed Central

    Bailey, Helen; Fossette, Sabrina; Bograd, Steven J.; Shillinger, George L.; Swithenbank, Alan M.; Georges, Jean-Yves; Gaspar, Philippe; Strömberg, K. H. Patrik; Paladino, Frank V.; Spotila, James R.; Block, Barbara A.; Hays, Graeme C.

    2012-01-01

    Foraging success for pelagic vertebrates may be revealed by horizontal and vertical movement patterns. We show markedly different patterns for leatherback turtles in the North Atlantic versus Eastern Pacific, which feed on gelatinous zooplankton that are only occasionally found in high densities. In the Atlantic, travel speed was characterized by two modes, indicative of high foraging success at low speeds (<15 km d−1) and transit at high speeds (20–45 km d−1). Only a single mode was evident in the Pacific, which occurred at speeds of 21 km d−1 indicative of transit. The mean dive depth was more variable in relation to latitude but closer to the mean annual depth of the thermocline and nutricline for North Atlantic than Eastern Pacific turtles. The most parsimonious explanation for these findings is that Eastern Pacific turtles rarely achieve high foraging success. This is the first support for foraging behaviour differences between populations of this critically endangered species and suggests that longer periods searching for prey may be hindering population recovery in the Pacific while aiding population maintenance in the Atlantic. PMID:22615767

  4. Movement patterns for a critically endangered species, the leatherback turtle (Dermochelys coriacea), linked to foraging success and population status.

    PubMed

    Bailey, Helen; Fossette, Sabrina; Bograd, Steven J; Shillinger, George L; Swithenbank, Alan M; Georges, Jean-Yves; Gaspar, Philippe; Strömberg, K H Patrik; Paladino, Frank V; Spotila, James R; Block, Barbara A; Hays, Graeme C

    2012-01-01

    Foraging success for pelagic vertebrates may be revealed by horizontal and vertical movement patterns. We show markedly different patterns for leatherback turtles in the North Atlantic versus Eastern Pacific, which feed on gelatinous zooplankton that are only occasionally found in high densities. In the Atlantic, travel speed was characterized by two modes, indicative of high foraging success at low speeds (<15 km d(-1)) and transit at high speeds (20-45 km d(-1)). Only a single mode was evident in the Pacific, which occurred at speeds of 21 km d(-1) indicative of transit. The mean dive depth was more variable in relation to latitude but closer to the mean annual depth of the thermocline and nutricline for North Atlantic than Eastern Pacific turtles. The most parsimonious explanation for these findings is that Eastern Pacific turtles rarely achieve high foraging success. This is the first support for foraging behaviour differences between populations of this critically endangered species and suggests that longer periods searching for prey may be hindering population recovery in the Pacific while aiding population maintenance in the Atlantic. PMID:22615767

  5. Histopathological pattern of gonads in cases of sex abnormalities in dogs: An attempt of morphological evaluation involving potential for neoplasia.

    PubMed

    Dzimira, Stanislaw; Nizanski, Wojciech; Ochota, Malgorzata; Madej, Janusz A

    2015-10-01

    Disturbances in sex differentiation (DSD - disorder of sexual development) may result from disturbances in sex chromosomes or a disturbed development of gonads, or from genotypic disturbances. The objective of this article is to describe the histological structure of gonads in dogs showing sexual disturbances and a case of a cancer resembling gonadoblastoma in one of the animals. Among the 10 examined dogs with disturbances of sex development only a single case of a gonadoblastoma was observed. In animals with sex disturbances, similarly to humans, there exists a potential tendency for neoplastic lesions in dysgenetic gonads. As a rule, its frequency in population is confined due to the early procedure of castration of non-breeding dogs. In the present study dogs demonstrated phenotypical traits of bitches with developmental anomalies such as hyperplastic clitoris with vestigial os penis (baculum), or abnormalities in the location and structure of the vulva. The material for the study included canine gonads of various breeds, sampled from phenotypical bitches, aged 7 months to 4 years - patients of the Department of Reproduction and Clinic of Farm Animals, Faculty of Veterinary Medicine, University of Environmental and Life Sciences in Wroclaw (Poland) in years 2006-2013. The organs were surgically removed from the abdomen and sent for histopathological examination for the purpose of determining their histological structure. The 10 examined cases of altered gonads included 6 bilateral cases of testes (60%), 2 cases of bilateral ovotestis (20%), one case of co-manifestation of testis and ovotestis (10%), and a single case of a testis and a neoplastically altered gonad (gonadoblastoma) (10%).

  6. Aberrant gene expression patterns in placentomes are associated with phenotypically normal and abnormal cattle cloned by somatic cell nuclear transfer.

    PubMed

    Everts, Robin E; Chavatte-Palmer, Pascale; Razzak, Anthony; Hue, Isabelle; Green, Cheryl A; Oliveira, Rosane; Vignon, Xavier; Rodriguez-Zas, Sandra L; Tian, X Cindy; Yang, Xiangzhong; Renard, Jean-Paul; Lewin, Harris A

    2008-03-14

    Transcription profiling of placentomes derived from somatic cell nuclear transfer (SCNT, n = 20), in vitro fertilization (IVF, n = 9), and artificial insemination (AI, n = 9) at or near term development was performed to better understand why SCNT and IVF often result in placental defects, hydrops, and large offspring syndrome (LOS). Multivariate analysis of variance was used to distinguish the effects of SCNT, IVF, and AI on gene expression, taking into account the effects of parturition (term or preterm), sex of fetus, breed of dam, breed of fetus, and pathological finding in the offspring (hydrops, normal, or other abnormalities). Differential expression of 20 physiologically important genes was confirmed with quantitative PCR. The largest effect on placentome gene expression was attributable to whether placentas were collected at term or preterm (i.e., whether the collection was because of disease or to obtain stage-matched controls) followed by placentome source (AI, IVF, or SCNT). Gene expression in SCNT placentomes was dramatically different from AI (n = 336 genes; 276 >2-fold) and from IVF (n = 733 genes; 162 >2-fold) placentomes. Functional analysis of differentially expressed genes (DEG) showed that IVF has significant effects on genes associated with cellular metabolism. In contrast, DEG associated with SCNT are involved in multiple pathways, including cell cycle, cell death, and gene expression. Many DEG were shared between the gene lists for IVF and SCNT comparisons, suggesting that common pathways are affected by the embryo culture methods used for IVF and SCNT. However, the many unique gene functions and pathways affected by SCNT suggest that cloned fetuses may be starved and accumulating toxic wastes due to placental insufficiency caused by reprogramming errors. Many of these genes are candidates for hydrops and LOS.

  7. Congenital mirror movements.

    PubMed Central

    Schott, G D; Wyke, M A

    1981-01-01

    In this report are described seven patients assessed clinically and neuropsychologically in whom mirror movements affecting predominantly the hands occurred as a congenital disorder. These mirror movements, representing a specific type of abnormal synkinesia, may arise as a hereditary condition, in the presence of a recognisable underlying neurological abnormality, and sporadically, and the seven patients provide more or less satisfactory examples of each of these three groups. Despite the apparent uniformity of the disorder, the heterogeneity and variability may be marked, examples in some of our patients including the pronounced increase in tone that developed with arm movement, and the capacity for modulation of the associated movement by alteration of neck position and bio-feedback. Various possible mechanisms are considered; these include impaired cerebral inhibition of unwanted movements, and functioning of abnormal motor pathways. Emphasis has been placed on the putative role of the direct, crossed corticomotoneurone pathways and on the unilateral and bilateral cerebral events that precede movement. PMID:7288446

  8. Source Water Flow Pathways In Forested, Mountain, Headwater Streams: A Link Between Sediment Movement Patterns And Stream Water Chemistry.

    NASA Astrophysics Data System (ADS)

    Martin, S.; Conklin, M. H.; Liu, F.

    2015-12-01

    Three years of continuous and discrete sediment and water quality data, from four forested, mountain, headwater catchments in the Sierra Nevada, is used to identify water sources, determine the importance of sub-surface flow pathways, detect any changes in source waters due to seasonal variation or drought, and link flow pathways with observed patterns of in-channel sediment movement within the study watersheds. Patterns in stream chemistry and turbidity point to infiltration as the dominant flow pathway within these catchments. Data support a flow pathway conceptual model in which precipitation water infiltrates into the shallow or deeper subsurface, increasing the hydraulic head of the water table and pushing pre-event water into the stream ahead of event water. Study catchments contain perennial streams and are characterized by a Mediterranean climate with a distinct wet and dry season. Sites are located in the rain-snow transition zone with snow making up 40 to 60 percent of average annual precipitation. Barring human disturbances such as logging/grazing (compaction) or fire (hydrophobicity), catchment soils have high infiltration capacities. Springs and seeps maintain baseflow during the summer low-flow season, and shifting chemical signals within the streams indicate the increased importance of sub-surface water sources during drought years. End-member mixing analysis was conducted to identify possible water end members. Turbidity hysteresis patterns described by previous studies show in-channel sources are dominant for discharge events year round, and there is no difference in fine sediment delivery to streams with or without a soil protecting layer of snow on the land surface. The dominance of sub-surface water sources and evidence for infiltration flow fits with turbidity data, as little material is reaching the stream due to erosive overland flow. An understanding of flow pathways provides a foundation for sustainable land use management in forested

  9. Wintering ecology of sympatric subspecies of Sandhill Crane: Correlations between body size, site fidelity, and movement patterns

    USGS Publications Warehouse

    Ivey, Gary L.; Dugger, Bruce D.; Herziger, Caroline P.; Casazza, Michael L.; Fleskes, Joseph P.

    2015-01-01

    Body size is known to correlate with many aspects of life history in birds, and this knowledge can be used to manage and conserve bird species. However, few studies have compared the wintering ecology of sympatric subspecies that vary significantly in body size. We used radiotelemetry to examine the relationship between body size and site fidelity, movements, and home range in 2 subspecies of Sandhill Crane (Grus canadensis) wintering in the Sacramento–San Joaquin Delta of California, USA. Both subspecies showed high interannual return rates to the Delta study area, but Greater Sandhill Cranes (G. c. tabida) showed stronger within-winter fidelity to landscapes in our study region and to roost complexes within landscapes than did Lesser Sandhill Cranes (G. c. canadensis). Foraging flights from roost sites were shorter for G. c. tabida than for G. c. canadensis (1.9 ± 0.01 km vs. 4.5 ± 0.01 km, respectively) and, consequently, the mean size of 95% fixed-kernel winter home ranges was an order of magnitude smaller for G. c. tabida than for G. c. canadensis (1.9 ± 0.4 km2 vs. 21.9 ± 1.9 km2, respectively). Strong site fidelity indicates that conservation planning to manage for adequate food resources around traditional roost sites can be effective for meeting the habitat needs of these cranes, but the scale of conservation efforts should differ by subspecies. Analysis of movement patterns suggests that conservation planners and managers should consider all habitats within 5 km of a known G. c. tabida roost and within 10 km of a G. c. canadensis roost when planning for habitat management, mitigation, acquisition, and easements.

  10. Expression of ERα and PR in Various Morphological Patterns of Abnormal Uterine Bleeding-Endometrial causes in Reproductive Age Group

    PubMed Central

    Singh, Pallavi; Chaurasia, Amrita; Dhingra, Vishal; Misra, Vatsala

    2016-01-01

    Introduction Abnormal Uterine Bleeding (AUB) is most common gynaecological problem but its management is not well defined. So FIGO/PALMCOEIN classification was developed to provide clear management options as treatment is different in PALM and AUB-E group. FIGO/PALM-COEIN classification and immunohistochemistry with ERα and PR expression in AUB-E group will be helpful in management of these patients, thus preventing surgical interventions. Aim To study histomorphological classification according to FIGO/PALM-COEIN classification in patients presenting with AUB into PALM and AUB-E group. To study the receptor expression of ERα and PR in AUB-E group. Materials and Methods This cross sectional study was performed in patients presenting with AUB in reproductive age group (15-45 years). Six hundred endometrial specimens were stained with H&E for histolomorphological examination and classified as per FIGO/PALM-COEIN classification of AUB in non-gravid women in reproductive age group. Fifty endometrial biopsies were of pregnancy and pregnancy related complications and were excluded from study. A total of 550 samples were evaluated in present study. IHC for quantification of ERα and PR expression was carried out in AUB-E (100) cases and control group endometrium (20) cases due to technical constraints. Statistical Analysis Unpaired student t-test was performed. p-value ≤ 0.05 was taken as critical level of significance. Results Endometrial (58.19%) (AUB-E) causes were most common cause of AUB. Most common morphology was AUB-E (Proliferative endometrium), AUB-L (Leiomyoma) and AUB-E (Secretory endometrium) respectively. Statistically significant expression of ERα and PR was found in AUB-E endometrium as compared to control group endometrium. In Non secretory/Proliferative endometrium AUB-E group. Proliferative endometrium and hyperplasia without atypia had significant expression of ERα and PR in glands and stroma when compared with proliferative phase control group

  11. Morphological abnormalities among lampreys

    USGS Publications Warehouse

    Manion, Patrick J.

    1967-01-01

    The experimental control of the sea lamprey (Petromyzon marinus) in the Great Lakes has required the collection of thousands of lampreys. Representatives of each life stage of the four species of the Lake Superior basin were examined for structural abnormalities. The most common aberration was the presence of additional tails. The accessory tails were always postanal and smaller than the normal tail. The point of origin varied; the extra tails occurred on dorsal, ventral, or lateral surfaces. Some of the extra tails were misshaped and curled, but others were normal in shape and pigment pattern. Other abnormalities in larval sea lampreys were malformed or twisted tails and bodies. The cause of the structural abnormalities is unknown. The presence of extra caudal fins could be genetically controlled, or be due to partial amputation or injury followed by abnormal regeneration. Few if any lampreys with structural abnormalities live to sexual maturity.

  12. Abnormal N-glycosylation pattern for brain nucleotide pyrophosphatase-5 (NPP-5) in Mecp2-mutant murine models of Rett syndrome.

    PubMed

    Cortelazzo, Alessio; De Felice, Claudio; Guerranti, Roberto; Signorini, Cinzia; Leoncini, Silvia; Pecorelli, Alessandra; Scalabrì, Francesco; Madonna, Michele; Filosa, Stefania; Della Giovampaola, Cinzia; Capone, Antonietta; Durand, Thierry; Mirasole, Cristiana; Zolla, Lello; Valacchi, Giuseppe; Ciccoli, Lucia; Guy, Jacky; D'Esposito, Maurizio; Hayek, Joussef

    2016-04-01

    Neurological disorders can be associated with protein glycosylation abnormalities. Rett syndrome is a devastating genetic brain disorder, mainly caused by de novo loss-of-function mutations in the methyl-CpG binding protein 2 (MECP2) gene. Although its pathogenesis appears to be closely associated with a redox imbalance, no information on glycosylation is available. Glycoprotein detection strategies (i.e., lectin-blotting) were applied to identify target glycosylation changes in the whole brain of Mecp2 mutant murine models of the disease. Remarkable glycosylation pattern changes for a peculiar 50kDa protein, i.e., the N-linked brain nucleotide pyrophosphatase-5 were evidenced, with decreased N-glycosylation in the presymptomatic and symptomatic mutant mice. Glycosylation changes were rescued by selected brain Mecp2 reactivation. Our findings indicate that there is a causal link between the amount of Mecp2 and the N-glycosylation of NPP-5.

  13. Meiotic abnormalities

    SciTech Connect

    1993-12-31

    Chapter 19, describes meiotic abnormalities. These include nondisjunction of autosomes and sex chromosomes, genetic and environmental causes of nondisjunction, misdivision of the centromere, chromosomally abnormal human sperm, male infertility, parental age, and origin of diploid gametes. 57 refs., 2 figs., 1 tab.

  14. Use of social network analysis to characterize the pattern of animal movements in the initial phases of the 2001 foot and mouth disease (FMD) epidemic in the UK.

    PubMed

    Ortiz-Pelaez, A; Pfeiffer, D U; Soares-Magalhães, R J; Guitian, F J

    2006-09-15

    Aggregated movement data do not take into account the relative position of the units within a higher-level structure. Social network analysis (SNA) and graph theory provide a tool to organise and analyse relational data overcoming the limitations of standard methods where the position of individuals/observations does not affect the result of the analysis. Some recorded movements of cattle and sheep during the initial phase of the 2001 foot and mouth disease (FMD) outbreak in the UK, before the ban on animal movements was imposed, are analysed descriptively using SNA. With the data available, a directed dichotomized network with 653 nodes and 797 arches was analysed. Most of the 10 nodes with the highest betweenness (3 farms, 4 markets and 3 dealers) were identified as key players in the initial spread of the infection. Three groups of nodes with distinctive proportion of k < or = 2 neighbours would result in three different theoretical outbreak dimensions assuming that the infection is only disseminated by the movements included in the network: no spread, spread up to 7% and around 25%. There are three hierarchical clusters with 308, 215 and 130 nodes, respectively. Farms in cluster 1 appear to be more similar in their movement patterns to non-farm holdings than to farms in clusters 2 and 3. Relative betweenness, k-neighbours and structural equivalence using hierarchical clustering were able to identify key actors in the evolution of the initial phases of the FMD outbreak such as markets, dealers and farms with atypical movement patterns. Holdings with high betweenness, large number of k < or = 2 neighbours and with movement pattern as in cluster 1 should be targeted in disease control activities once primary actors like markets, dealers and slaughter houses have been contained. PMID:16769142

  15. Uneven large-scale movement patterns in wild and reintroduced pre-adult bearded vultures: conservation implications.

    PubMed

    Margalida, Antoni; Carrete, Martina; Hegglin, Daniel; Serrano, David; Arenas, Rafael; Donázar, José A

    2013-01-01

    After the quasi-extinction of much of the European vertebrate megafauna during the last few centuries, many reintroduction projects seek to restore decimated populations. However, the future of numerous species depends on the management scenarios of metapopulations where the flow of individuals can be critical to ensure their viability. This is the case of the bearded vulture Gypaetus barbatus, an Old World, large body-sized and long-lived scavenger living in mountain ranges. Although persecution in Western Europe restrained it to the Pyrenees, the species is nowadays present in other mountains thanks to reintroduction projects. We examined the movement patterns of pre-adult non-breeding individuals born in the wild population of the Pyrenees (n = 9) and in the reintroduced populations of the Alps (n = 24) and Andalusia (n = 13). Most birds were equipped with GPS-GSM radio transmitters, which allowed accurate determination of individual dispersal patterns. Two estimators were considered: i) step length (i.e., the distance travelled per day by each individual, calculated considering only successive days); and ii) total dispersal distance (i.e., the distance travelled between each mean daily location and the point of release). Both dispersal estimators showed a positive relationship with age but were also highly dependent on the source population, birds in Andalusia and Alps moving farther than in Pyrenees. Future research should confirm if differences in dispersal distances are the rule, in which case the dynamics of future populations would be strongly influenced. In summary, our findings highlight that inter-population differences can affect the flow of individuals among patches (a key aspect to ensure the viability of the European metapopulation of the endangered bearded vulture), and thus should be taken into account when planning reintroduction programs. This result also raises questions about whether similar scenarios may occur in other restoration

  16. Uneven large-scale movement patterns in wild and reintroduced pre-adult bearded vultures: conservation implications.

    PubMed

    Margalida, Antoni; Carrete, Martina; Hegglin, Daniel; Serrano, David; Arenas, Rafael; Donázar, José A

    2013-01-01

    After the quasi-extinction of much of the European vertebrate megafauna during the last few centuries, many reintroduction projects seek to restore decimated populations. However, the future of numerous species depends on the management scenarios of metapopulations where the flow of individuals can be critical to ensure their viability. This is the case of the bearded vulture Gypaetus barbatus, an Old World, large body-sized and long-lived scavenger living in mountain ranges. Although persecution in Western Europe restrained it to the Pyrenees, the species is nowadays present in other mountains thanks to reintroduction projects. We examined the movement patterns of pre-adult non-breeding individuals born in the wild population of the Pyrenees (n = 9) and in the reintroduced populations of the Alps (n = 24) and Andalusia (n = 13). Most birds were equipped with GPS-GSM radio transmitters, which allowed accurate determination of individual dispersal patterns. Two estimators were considered: i) step length (i.e., the distance travelled per day by each individual, calculated considering only successive days); and ii) total dispersal distance (i.e., the distance travelled between each mean daily location and the point of release). Both dispersal estimators showed a positive relationship with age but were also highly dependent on the source population, birds in Andalusia and Alps moving farther than in Pyrenees. Future research should confirm if differences in dispersal distances are the rule, in which case the dynamics of future populations would be strongly influenced. In summary, our findings highlight that inter-population differences can affect the flow of individuals among patches (a key aspect to ensure the viability of the European metapopulation of the endangered bearded vulture), and thus should be taken into account when planning reintroduction programs. This result also raises questions about whether similar scenarios may occur in other restoration

  17. The Use of Satellite Tags to Redefine Movement Patterns of Spiny Dogfish (Squalus acanthias) along the U.S. East Coast: Implications for Fisheries Management

    PubMed Central

    Carlson, Amy E.; Hoffmayer, Eric R.; Tribuzio, Cindy A.; Sulikowski, James A.

    2014-01-01

    Spiny dogfish (Squalus acanthias) are assumed to be a highly migratory species, making habitual north-south migrations throughout their northwestern Atlantic United States (U.S.) range. Also assumed to be a benthic species, spiny dogfish stock structure is estimated through Northeast Fisheries Science Center (NEFSC) bottom-trawl surveys. Recent anomalies in population trends, including a recent four-fold increase in estimated spawning stock biomass, suggest alternative movement patterns could exist for this shark species. To obtain a better understanding of the horizontal and vertical movement dynamics of this species, Microwave Telemetry pop-up satellite archival X-Tags were attached to forty adult spiny dogfish at the northern (Gulf of Maine) and southern (North Carolina) extents of their core U.S. geographic range. Reconstructed geolocation tracks ranging in lengths from two to 12 months suggest that the seasonal migration patterns appear to be local in nature to each respective northern and southern deployment site, differing from previously published migration paradigms. Differences in distance and direction traveled between seasonal geolocations possibly indicate separate migratory patterns between groups. Kernel utilization distribution models also suggest strong separate core home ranges. Significant differences in seasonal temperature and depths between the two regions further substantiate the possibility of separate regional movement patterns between the two groups. Vertical utilization also suggests distinct diel patterns and that this species may not utilize the benthos as previously thought, potentially decreasing availability to benthic gear. PMID:25068584

  18. The use of satellite tags to redefine movement patterns of spiny dogfish (Squalus acanthias) along the U.S. east coast: implications for fisheries management.

    PubMed

    Carlson, Amy E; Hoffmayer, Eric R; Tribuzio, Cindy A; Sulikowski, James A

    2014-01-01

    Spiny dogfish (Squalus acanthias) are assumed to be a highly migratory species, making habitual north-south migrations throughout their northwestern Atlantic United States (U.S.) range. Also assumed to be a benthic species, spiny dogfish stock structure is estimated through Northeast Fisheries Science Center (NEFSC) bottom-trawl surveys. Recent anomalies in population trends, including a recent four-fold increase in estimated spawning stock biomass, suggest alternative movement patterns could exist for this shark species. To obtain a better understanding of the horizontal and vertical movement dynamics of this species, Microwave Telemetry pop-up satellite archival X-Tags were attached to forty adult spiny dogfish at the northern (Gulf of Maine) and southern (North Carolina) extents of their core U.S. geographic range. Reconstructed geolocation tracks ranging in lengths from two to 12 months suggest that the seasonal migration patterns appear to be local in nature to each respective northern and southern deployment site, differing from previously published migration paradigms. Differences in distance and direction traveled between seasonal geolocations possibly indicate separate migratory patterns between groups. Kernel utilization distribution models also suggest strong separate core home ranges. Significant differences in seasonal temperature and depths between the two regions further substantiate the possibility of separate regional movement patterns between the two groups. Vertical utilization also suggests distinct diel patterns and that this species may not utilize the benthos as previously thought, potentially decreasing availability to benthic gear.

  19. Multi-channel EEG signal feature extraction and pattern recognition on horizontal mental imagination task of 1-D cursor movement for brain computer interface.

    PubMed

    Serdar Bascil, M; Tesneli, Ahmet Y; Temurtas, Feyzullah

    2015-06-01

    Brain computer interfaces (BCIs), based on multi-channel electroencephalogram (EEG) signal processing convert brain signal activities to machine control commands. It provides new communication way with a computer by extracting electroencephalographic activity. This paper, deals with feature extraction and classification of horizontal mental task pattern on 1-D cursor movement from EEG signals. The hemispherical power changes are computed and compared on alpha & beta frequencies and horizontal cursor control extracted with only mental imagination of cursor movements. In the first stage, features are extracted with the well-known average signal power or power difference (alpha and beta) method. Principal component analysis is used for reducing feature dimensions. All features are classified and the mental task patterns are recognized by three neural network classifiers which learning vector quantization, multilayer neural network and probabilistic neural network due to obtaining acceptable good results and using successfully in pattern recognition via k-fold cross validation technique.

  20. Craniofacial Abnormalities

    MedlinePlus

    ... of the skull and face. Craniofacial abnormalities are birth defects of the face or head. Some, like cleft ... palate, are among the most common of all birth defects. Others are very rare. Most of them affect ...

  1. Chromosome Abnormalities

    MedlinePlus

    ... decade, newer techniques have been developed that allow scientists and doctors to screen for chromosomal abnormalities without using a microscope. These newer methods compare the patient's DNA to a normal DNA ...

  2. Walking abnormalities

    MedlinePlus

    ... include: Arthritis of the leg or foot joints Conversion disorder (a psychological disorder) Foot problems (such as a ... injuries. For an abnormal gait that occurs with conversion disorder, counseling and support from family members are strongly ...

  3. Nail abnormalities

    MedlinePlus

    Beau's lines; Fingernail abnormalities; Spoon nails; Onycholysis; Leukonychia; Koilonychia; Brittle nails ... Just like the skin, the fingernails tell a lot about your health: ... the fingernail. These lines can occur after illness, injury to ...

  4. Eye-Head Coordination Abnormalities in Schizophrenia

    PubMed Central

    Schwab, Simon; Würmle, Othmar; Razavi, Nadja; Müri, René M.; Altorfer, Andreas

    2013-01-01

    Background Eye-movement abnormalities in schizophrenia are a well-established phenomenon that has been observed in many studies. In such studies, visual targets are usually presented in the center of the visual field, and the subject's head remains fixed. However, in every-day life, targets may also appear in the periphery. This study is among the first to investigate eye and head movements in schizophrenia by presenting targets in the periphery of the visual field. Methodology/Principal Findings Two different visual recognition tasks, color recognition and Landolt orientation tasks, were presented at the periphery (at a visual angle of 55° from the center of the field of view). Each subject viewed 96 trials, and all eye and head movements were simultaneously recorded using video-based oculography and magnetic motion tracking of the head. Data from 14 patients with schizophrenia and 14 controls were considered. The patients had similar saccadic latencies in both tasks, whereas controls had shorter saccadic latencies in the Landolt task. Patients performed more head movements, and had increased eye-head offsets during combined eye-head shifts than controls. Conclusions/Significance Patients with schizophrenia may not be able to adapt to the two different tasks to the same extent as controls, as seen by the former's task-specific saccadic latency pattern. This can be interpreted as a specific oculomotoric attentional dysfunction and may support the hypothesis that schizophrenia patients have difficulties determining the relevance of stimuli. Patients may also show an uneconomic over-performance of head-movements, which is possibly caused by alterations in frontal executive function that impair the inhibition of head shifts. In addition, a model was created explaining 93% of the variance of the response times as a function of eye and head amplitude, which was only observed in the controls, indicating abnormal eye-head coordination in patients with schizophrenia. PMID

  5. Movement Patterns of American Shad Transported Upstream of Dams on The Roanoke River, North Carolina and Virginia

    USGS Publications Warehouse

    Harris, Julianne E.; Hightower, J.E.

    2011-01-01

    American shad Alosa sapidissima are in decline throughout much of their native range as a result of overfishing, pollution, and habitat alteration in coastal rivers where they spawn. One approach to restoration in regulated rivers is to provide access to historical spawning habitat above dams through a trap-and-transport program. We examined the initial survival, movement patterns, spawning, and downstream passage of sonic-tagged adult American shad transported to reservoir and riverine habitats upstream of hydroelectric dams on the Roanoke River, North Carolina and Virginia, during 2007–2009. Average survival to release in 2007–2008 was 85%, but survival decreased with increasing water temperature. Some tagged fish released in reservoirs migrated upstream to rivers; however, most meandered back and forth within the reservoir. A higher percentage of fish migrated through a smaller (8,215-ha) than a larger (20,234-ha) reservoir, suggesting that the population-level effects of transport may depend on upper basin characteristics. Transported American shad spent little time in upper basin rivers but were there when temperatures were appropriate for spawning. No American shad eggs were collected during weekly plankton sampling in upper basin rivers. The estimated initial survival of sonic-tagged American shad after downstream passage through each dam was 71–100%; however, only 1% of the detected fish migrated downstream through all three dams and many were relocated just upstream of a dam late in the season. Although adult American shad were successfully transported to upstream habitats in the Roanoke River basin, under present conditions transported individuals may have reduced effective fecundity and postspawning survival compared with nontransported fish that spawn in the lower Roanoke River.

  6. Multiscale patterns of movement in fragmented landscapes and consequences on demography of the snail kite in Florida

    USGS Publications Warehouse

    Martin, J.; Nichols, J.D.; Kitchens, W.M.; Hines, J.E.

    2006-01-01

    1. Habitat loss and fragmentation are major factors affecting vertebrate populations. A major effect of these habitat alterations is that they reduce movement of organisms. Despite the accepted importance of movement in driving the dynamics of many natural populations, movement of vertebrates in fragmented landscapes have seldom been estimated with robust statistical methods. 2. We estimated movement probabilities of snail kites Rosthramus sociabilis within the remaining wetlands in Florida. Using both radio-telemetry and banding information, we used a multistate modelling approach to estimate transition probabilities at two temporal scales (month; year) and multiple spatial scales. We examined kite movement among wetlands altered by three different levels of fragmentation: among wetlands separated by small physical barriers (e.g. road); among wetlands separated by moderate amount of matrix ( 15 km). 3. Kites moved extensively among contiguous wetlands (movement probability 0?29 per month), but significantly less among isolated wetlands (movement probability 0?10 per month). 4. Kites showed high levels of annual site fidelity to most isolated wetlands (probability ranged from 0?72 to 0?95 per year). 5. We tested the effects of patch size and interpatch distance on movement. Our modelling indicated an effect of both distance and patch size on juveniles' movement (but not adult) when examining movements among fragments. 6. Only a small proportion of kites escaped a regional drought by moving to refugia (wetlands less affected by drought). Many individuals died after the drought. During drought adult survival dropped by 16% while juvenile survival dropped by 86% (possibly because juveniles were less likely to reach refugia). 7. We hypothesize that fragmentation may decrease kite's resistance to drought by restricting exploratory behaviour.

  7. Multiscale patterns of movement in fragmented landscapes and consequences on demography of the snail kite in Florida.

    PubMed

    Martin, Julien; Nichols, James D; Kitchens, Wiley M; Hines, James E

    2006-03-01

    1. Habitat loss and fragmentation are major factors affecting vertebrate populations. A major effect of these habitat alterations is that they reduce movement of organisms. Despite the accepted importance of movement in driving the dynamics of many natural populations, movement of vertebrates in fragmented landscapes have seldom been estimated with robust statistical methods. 2. We estimated movement probabilities of snail kites Rosthramus sociabilis within the remaining wetlands in Florida. Using both radio-telemetry and banding information, we used a multistate modelling approach to estimate transition probabilities at two temporal scales (month; year) and multiple spatial scales. We examined kite movement among wetlands altered by three different levels of fragmentation: among wetlands separated by small physical barriers (e.g. road); among wetlands separated by moderate amount of matrix (< 5 km); and among wetlands separated by extensive matrix areas (> 15 km). 3. Kites moved extensively among contiguous wetlands (movement probability 0.29 per month), but significantly less among isolated wetlands (movement probability 0.10 per month). 4. Kites showed high levels of annual site fidelity to most isolated wetlands (probability ranged from 0.72 to 0.95 per year). 5. We tested the effects of patch size and interpatch distance on movement. Our modelling indicated an effect of both distance and patch size on juveniles' movement (but not adult) when examining movements among fragments. 6. Only a small proportion of kites escaped a regional drought by moving to refugia (wetlands less affected by drought). Many individuals died after the drought. During drought adult survival dropped by 16% while juvenile survival dropped by 86% (possibly because juveniles were less likely to reach refugia). 7. We hypothesize that fragmentation may decrease kite's resistance to drought by restricting exploratory behaviour.

  8. Space-Use Patterns of the Asiatic Wild Ass (Equus hemionus): Complementary Insights from Displacement, Recursion Movement and Habitat Selection Analyses.

    PubMed

    Giotto, Nina; Gerard, Jean-François; Ziv, Alon; Bouskila, Amos; Bar-David, Shirli

    2015-01-01

    The way in which animals move and use the landscape is influenced by the spatial distribution of resources, and is of importance when considering species conservation. We aimed at exploring how landscape-related factors affect a large herbivore's space-use patterns by using a combined approach, integrating movement (displacement and recursions) and habitat selection analyses. We studied the endangered Asiatic wild ass (Equus hemionus) in the Negev Desert, Israel, using GPS monitoring and direct observation. We found that the main landscape-related factors affecting the species' space-use patterns, on a daily and seasonal basis, were vegetation cover, water sources and topography. Two main habitat types were selected: high-elevation sites during the day (specific microclimate: windy on warm summer days) and streambed surroundings during the night (coupled with high vegetation when the animals were active in summer). Distribution of recursion times (duration between visits) revealed a 24-hour periodicity, a pattern that could be widespread among large herbivores. Characterizing frequently revisited sites suggested that recursion movements were mainly driven by a few landscape features (water sources, vegetation patches, high-elevation points), but also by social factors, such as territoriality, which should be further explored. This study provided complementary insights into the space-use patterns of E. hemionus. Understanding of the species' space-use patterns, at both large and fine spatial scale, is required for developing appropriate conservation protocols. Our approach could be further applied for studying the space-use patterns of other species in heterogeneous landscapes.

  9. Intra-population variation in activity ranges, diel patterns, movement rates, and habitat use of American alligators in a subtropical estuary

    USGS Publications Warehouse

    Rosenblatt, Adam E.; Heithaus, Michael R.; Mazzotti, Frank M; Cherkiss, Michael S.; Jeffery, Brian M.

    2013-01-01

    Movement and habitat use patterns are fundamental components of the behaviors of mobile animals and help determine the scale and types of interactions they have with their environments. These behaviors are especially important to quantify for top predators because they can have strong effects on lower trophic levels as well as the wider ecosystem. Many studies of top predator movement and habitat use focus on general population level trends, which may overlook important intra-population variation in behaviors that now appear to be common. In an effort to better understand the prevalence of intrapopulation variation in top predator movement behaviors and the potential effects of such variation on ecosystem dynamics, we examined the movement and habitat use patterns of a population of adult American alligators (Alligator mississippiensis) in a subtropical estuary for nearly four years. We found that alligators exhibited divergent behaviors with respect to activity ranges, movement rates, and habitat use, and that individualized behaviors were stable over multiple years. We also found that the variations across the three behavioral metrics were correlated such that consistent behavioral types emerged, specifically more exploratory individuals and more sedentary individuals. Our study demonstrates that top predator populations can be characterized by high degrees of intra-population variation in terms of movement and habitat use behaviors that could lead to individuals filling different ecological roles in the same ecosystem. By extension, one-size-fits-all ecosystem and species-specific conservation and management strategies that do not account for potential intra-population variation in top predator behaviors may not produce the desired outcomes in all cases.

  10. Intra-population variation in activity ranges, diel patterns, movement rates, and habitat use of American alligators in a subtropical estuary

    NASA Astrophysics Data System (ADS)

    Rosenblatt, Adam E.; Heithaus, Michael R.; Mazzotti, Frank J.; Cherkiss, Michael; Jeffery, Brian M.

    2013-12-01

    Movement and habitat use patterns are fundamental components of the behaviors of mobile animals and help determine the scale and types of interactions they have with their environments. These behaviors are especially important to quantify for top predators because they can have strong effects on lower trophic levels as well as the wider ecosystem. Many studies of top predator movement and habitat use focus on general population level trends, which may overlook important intra-population variation in behaviors that now appear to be common. In an effort to better understand the prevalence of intra-population variation in top predator movement behaviors and the potential effects of such variation on ecosystem dynamics, we examined the movement and habitat use patterns of a population of adult American alligators (Alligator mississippiensis) in a subtropical estuary for nearly four years. We found that alligators exhibited divergent behaviors with respect to activity ranges, movement rates, and habitat use, and that individualized behaviors were stable over multiple years. We also found that the variations across the three behavioral metrics were correlated such that consistent behavioral types emerged, specifically more exploratory individuals and more sedentary individuals. Our study demonstrates that top predator populations can be characterized by high degrees of intra-population variation in terms of movement and habitat use behaviors that could lead to individuals filling different ecological roles in the same ecosystem. By extension, one-size-fits-all ecosystem and species-specific conservation and management strategies that do not account for potential intra-population variation in top predator behaviors may not produce the desired outcomes in all cases.

  11. The internal auditory clock: what can evoked potentials reveal about the analysis of temporal sound patterns, and abnormal states of consciousness?

    PubMed

    Jones, S J

    2002-09-01

    internal "clocks"? Abnormal mismatch potentials may provide a manifestation of a disordered auditory time-sense, sometimes being abolished in comatose patients while the C-potentials and similar responses to the onset of tones are preserved. Both C- and M-potentials were usually found to be preserved, however, in patients who had emerged from coma and were capable of discriminating sounds. Substantially intact responses were also recorded from three patients who were functionally in a "vegetative" state. The C- and M-potentials were once again dissociated in a group of patients with multiple sclerosis, only the mismatch potentials being found to be significantly delayed. This subclinical impairment of a memory-based process responsible for the detection of change in temporal sound patterns may be related to defects in other memory domains such as working memory. PMID:12448181

  12. Abnormal movement of tropomyosin and response of myosin heads and actin during the ATPase cycle caused by the Arg167His, Arg167Gly and Lys168Glu mutations in TPM1 gene.

    PubMed

    Borovikov, Yurii S; Rysev, Nikita A; Chernev, Aleksey A; Avrova, Stanislava V; Karpicheva, Olga E; Borys, Danuta; Śliwińska, Małgorzata; Moraczewska, Joanna

    2016-09-15

    Amino acid substitutions: Arg167His, Arg167Gly and Lys168Glu, located in a consensus actin-binding site of the striated muscle tropomyosin Tpm1.1 (TM), were used to investigate mechanisms of the thin filament regulation. The azimuthal movement of TM strands on the actin filament and the responses of the myosin heads and actin subunits during the ATPase cycle were studied using fluorescence polarization of muscle fibres. The recombinant wild-type and mutant TMs labelled with 5-IAF, 1,5-IAEDANS-labelled S1and FITC-phalloidin F-actin were incorporated into the ghost muscle fibres to acquire information on the orientation of the probes relative to the fibre axis. The substitutions Arg167Gly and Lys168Glu shifted TM strands into the actin filament centre, whereas Arg167His moved TM towards the periphery of the filament. In the presence of Arg167Gly-TM and Lys168Glu-TM the fraction of actin monomers that were switched on and the number of the myosin heads strongly bound to F-actin were abnormally high even under conditions close to relaxation. In contrast, Arg167His-TM decreased the fraction of switched on actin and reduced the formation of strongly bound myosin heads throughout the ATPase cycle. We concluded that the altered TM-actin contacts destabilized the thin filament and affected the actin-myosin interactions.

  13. Abnormal movement of tropomyosin and response of myosin heads and actin during the ATPase cycle caused by the Arg167His, Arg167Gly and Lys168Glu mutations in TPM1 gene.

    PubMed

    Borovikov, Yurii S; Rysev, Nikita A; Chernev, Aleksey A; Avrova, Stanislava V; Karpicheva, Olga E; Borys, Danuta; Śliwińska, Małgorzata; Moraczewska, Joanna

    2016-09-15

    Amino acid substitutions: Arg167His, Arg167Gly and Lys168Glu, located in a consensus actin-binding site of the striated muscle tropomyosin Tpm1.1 (TM), were used to investigate mechanisms of the thin filament regulation. The azimuthal movement of TM strands on the actin filament and the responses of the myosin heads and actin subunits during the ATPase cycle were studied using fluorescence polarization of muscle fibres. The recombinant wild-type and mutant TMs labelled with 5-IAF, 1,5-IAEDANS-labelled S1and FITC-phalloidin F-actin were incorporated into the ghost muscle fibres to acquire information on the orientation of the probes relative to the fibre axis. The substitutions Arg167Gly and Lys168Glu shifted TM strands into the actin filament centre, whereas Arg167His moved TM towards the periphery of the filament. In the presence of Arg167Gly-TM and Lys168Glu-TM the fraction of actin monomers that were switched on and the number of the myosin heads strongly bound to F-actin were abnormally high even under conditions close to relaxation. In contrast, Arg167His-TM decreased the fraction of switched on actin and reduced the formation of strongly bound myosin heads throughout the ATPase cycle. We concluded that the altered TM-actin contacts destabilized the thin filament and affected the actin-myosin interactions. PMID:27480605

  14. Detecting eye movement abnormalities from concussion.

    PubMed

    Maruta, Jun; Ghajar, Jamshid

    2014-01-01

    An attention-based biomarker may be useful for concussion screening. A key role of attention is to generate time-based expectancies of specific sensory information, and it is postulated that postconcussion cognitive impairments and symptoms may stem from a primary deficit in this predictive timing mechanism. There is a close relationship between gaze and attention, but in addressing predictive timing, there is a need for an appropriate testing paradigm and methods to quantify oculomotor anomalies. We have utilized a continuous predictive visual tracking paradigm because human visual tracking requires predicting the temporal course of a stimulus and dynamically synchronizing the required action with the stimulus. We have shown that concussion patients often show disrupted gaze-target synchronization characterized by large gaze position error variability and overall phase advancement. Various attention components interact with visual tracking, and thus there is a possibility that different neurological and physiological conditions produce identifiable visual tracking characteristics. Analyzing neuromotor functions, specifically oculomotor synchronization, can provide a fast, accurate, and reliable assessment of cognitive functions.

  15. Exploiting Human Resource Requirements to Infer Human Movement Patterns for Use in Modelling Disease Transmission Systems: An Example from Eastern Province, Zambia.

    PubMed

    Alderton, Simon; Noble, Jason; Schaten, Kathrin; Welburn, Susan C; Atkinson, Peter M

    2015-01-01

    In this research, an agent-based model (ABM) was developed to generate human movement routes between homes and water resources in a rural setting, given commonly available geospatial datasets on population distribution, land cover and landscape resources. ABMs are an object-oriented computational approach to modelling a system, focusing on the interactions of autonomous agents, and aiming to assess the impact of these agents and their interactions on the system as a whole. An A* pathfinding algorithm was implemented to produce walking routes, given data on the terrain in the area. A* is an extension of Dijkstra's algorithm with an enhanced time performance through the use of heuristics. In this example, it was possible to impute daily activity movement patterns to the water resource for all villages in a 75 km long study transect across the Luangwa Valley, Zambia, and the simulated human movements were statistically similar to empirical observations on travel times to the water resource (Chi-squared, 95% confidence interval). This indicates that it is possible to produce realistic data regarding human movements without costly measurement as is commonly achieved, for example, through GPS, or retrospective or real-time diaries. The approach is transferable between different geographical locations, and the product can be useful in providing an insight into human movement patterns, and therefore has use in many human exposure-related applications, specifically epidemiological research in rural areas, where spatial heterogeneity in the disease landscape, and space-time proximity of individuals, can play a crucial role in disease spread.

  16. Exploiting Human Resource Requirements to Infer Human Movement Patterns for Use in Modelling Disease Transmission Systems: An Example from Eastern Province, Zambia.

    PubMed

    Alderton, Simon; Noble, Jason; Schaten, Kathrin; Welburn, Susan C; Atkinson, Peter M

    2015-01-01

    In this research, an agent-based model (ABM) was developed to generate human movement routes between homes and water resources in a rural setting, given commonly available geospatial datasets on population distribution, land cover and landscape resources. ABMs are an object-oriented computational approach to modelling a system, focusing on the interactions of autonomous agents, and aiming to assess the impact of these agents and their interactions on the system as a whole. An A* pathfinding algorithm was implemented to produce walking routes, given data on the terrain in the area. A* is an extension of Dijkstra's algorithm with an enhanced time performance through the use of heuristics. In this example, it was possible to impute daily activity movement patterns to the water resource for all villages in a 75 km long study transect across the Luangwa Valley, Zambia, and the simulated human movements were statistically similar to empirical observations on travel times to the water resource (Chi-squared, 95% confidence interval). This indicates that it is possible to produce realistic data regarding human movements without costly measurement as is commonly achieved, for example, through GPS, or retrospective or real-time diaries. The approach is transferable between different geographical locations, and the product can be useful in providing an insight into human movement patterns, and therefore has use in many human exposure-related applications, specifically epidemiological research in rural areas, where spatial heterogeneity in the disease landscape, and space-time proximity of individuals, can play a crucial role in disease spread. PMID:26421926

  17. Exploiting Human Resource Requirements to Infer Human Movement Patterns for Use in Modelling Disease Transmission Systems: An Example from Eastern Province, Zambia

    PubMed Central

    Alderton, Simon; Noble, Jason; Schaten, Kathrin; Welburn, Susan C.; Atkinson, Peter M.

    2015-01-01

    In this research, an agent-based model (ABM) was developed to generate human movement routes between homes and water resources in a rural setting, given commonly available geospatial datasets on population distribution, land cover and landscape resources. ABMs are an object-oriented computational approach to modelling a system, focusing on the interactions of autonomous agents, and aiming to assess the impact of these agents and their interactions on the system as a whole. An A* pathfinding algorithm was implemented to produce walking routes, given data on the terrain in the area. A* is an extension of Dijkstra’s algorithm with an enhanced time performance through the use of heuristics. In this example, it was possible to impute daily activity movement patterns to the water resource for all villages in a 75 km long study transect across the Luangwa Valley, Zambia, and the simulated human movements were statistically similar to empirical observations on travel times to the water resource (Chi-squared, 95% confidence interval). This indicates that it is possible to produce realistic data regarding human movements without costly measurement as is commonly achieved, for example, through GPS, or retrospective or real-time diaries. The approach is transferable between different geographical locations, and the product can be useful in providing an insight into human movement patterns, and therefore has use in many human exposure-related applications, specifically epidemiological research in rural areas, where spatial heterogeneity in the disease landscape, and space-time proximity of individuals, can play a crucial role in disease spread. PMID:26421926

  18. Haem degradation in abnormal haemoglobins.

    PubMed Central

    Brown, S B; Docherty, J C

    1978-01-01

    The coupled oxidation of certain abnormal haemoglobins leads to different bile-pigment isomer distributions from that of normal haemoglobin. The isomer pattern may be correlated with the structure of the abnormal haemoglobin in the neighbourhood of the haem pocket. This is support for haem degradation by an intramolecular reaction. PMID:708385

  19. Decoding sequential finger movements from preparatory activity in higher-order motor regions: a functional magnetic resonance imaging multi-voxel pattern analysis.

    PubMed

    Nambu, Isao; Hagura, Nobuhiro; Hirose, Satoshi; Wada, Yasuhiro; Kawato, Mitsuo; Naito, Eiichi

    2015-11-01

    Performing a complex sequential finger movement requires the temporally well-ordered organization of individual finger movements. Previous behavioural studies have suggested that the brain prepares a whole sequence of movements as a single set, rather than the movements of individual fingers. However, direct neuroimaging support for this hypothesis is lacking and, assuming it to be true, it remains unclear which brain regions represent the information of a prepared sequence. Here, we measured brain activity with functional magnetic resonance imaging while 14 right-handed healthy participants performed two types of well-learned sequential finger movements with their right hands. Using multi-voxel pattern analysis, we examined whether the types of the forthcoming sequence could be predicted from the preparatory activities of nine regions of interest, which included the motor, somatosensory and posterior parietal regions in each hemisphere, bilateral visual cortices, cerebellum and basal ganglia. We found that, during preparation, the activity of the contralateral motor regions could predict which of the two sequences would be executed. Further detailed analysis revealed that the contralateral dorsal premotor cortex and supplementary motor area were the key areas that contributed to the prediction consistently across participants. These contrasted with results from execution-related brain activity where a performed sequence was successfully predicted from the activities in the broad cortical sensory-motor network, including the bilateral motor, parietal and ipsilateral somatosensory cortices. Our study supports the hypothesis that temporary well-organized sequences of movements are represented as a set in the brain, and that preparatory activity in higher-order motor regions represents information about upcoming motor actions.

  20. Abundance, behavior, and movement patterns of western gray whales in relation to a 3-D seismic survey, Northeast Sakhalin Island, Russia.

    PubMed

    Gailey, Glenn; Würsig, Bernd; McDonald, Trent L

    2007-11-01

    A geophysical seismic survey was conducted in the summer of 2001 off the northeastern coast of Sakhalin Island, Russia. The area of seismic exploration was immediately adjacent to the Piltun feeding grounds of the endangered western gray whale (Eschrichtius robustus). This study investigates relative abundance, behavior, and movement patterns of gray whales in relation to occurrence and proximity to the seismic survey by employing scan sampling, focal follow, and theodolite tracking methodologies. These data were analyzed in relation to temporal, environmental, and seismic related variables to evaluate potential disturbance reactions of gray whales to the seismic survey. The relative numbers of whales and pods recorded from five shore-based stations were not significantly different during periods when seismic surveys were occurring compared to periods when no seismic surveys were occurring and to the post-seismic period. Univariate analyses indicated no significant statistical correlation between seismic survey variables and any of the eleven movement and behavior variables. Multiple regression analyses indicated that, after accounting for temporal and environmental variables, 6 of 11 movement and behavior variables (linearity, acceleration, mean direction, blows per surfacing, and surface-dive blow rate) were not significantly associated with seismic survey variables, and 5 of 11 variables (leg speed, reorientation rate, distance-from-shore, blow interval, and dive time) were significantly associated with seismic survey variables. In summary, after accounting for environmental variables, no correlation was found between seismic survey variables and the linearity of whale movements, changes in whale swimming speed between theodolite fixes, mean direction of whale movement, mean number of whale exhalations per minute at the surface, mean time at the surface, and mean number of exhalations per minute during a whales surface-to-dive cycle. In contrast, at higher

  1. Prevalence and pattern of abnormal myocardial perfusion in patients with isolated coronary artery ectasia: study by 99mTc-sestamibi radionuclide scintigraphy.

    PubMed

    Ismail, Ahmed M; Rayan, Mona; Adel, Amr; Demerdash, Salah; Atef, Mohamed; Abdallah, Mohamed; Nammas, Wail

    2014-02-01

    We explored the prevalence and pattern of abnormal myocardial perfusion in patients with isolated coronary artery ectasia (CAE), as demonstrated by (99m)Tc-sestamibi scintigraphy. Prospectively, we enrolled 35 patients with angiographically documented CAE and no significant coronary obstruction, who underwent elective coronary angiography. Patients underwent Stress-rest (99m)Tc-sestamibi scintigraphy within 4 days of coronary angiography. They were divided into 2 groups: group I: with normal perfusion scan; and group II: with reversible perfusion defects. The mean age was 49.6 ± 6.9 years; 34 (97.1 %) were males. Seventy-nine (75.2 %) arteries were affected by CAE. Among 79 arteries affected by CAE, affection was diffuse in 37 (46.8 %). Thirteen (37.1 %) patients had normal perfusion scan (group I), whereas 22 (62.9 %) had reversible perfusion defects (group II). Among 22 patients with reversible perfusion defects, 20 (90.9 %) had mild and 2 (9.1 %) had moderate ischemia. Among 49 myocardial segments with reversible perfusion defects, 22 (44.9 %) were basal, 18 (36.7 %) mid-, and 9 (18.4 %) apical segments. Diffuse CAE was significantly more prevalent in group II versus group I, in all 3 major coronary arteries (p < 0.05 for all). In patients with isolated CAE who underwent elective coronary angiography, reversible perfusion defects demonstrated by (99m)Tc-sestamibi scintigraphy were rather prevalent, mostly mild, more likely to affect the basal and mid-segments of the myocardium, and more frequently associated with diffuse ectasia.

  2. The division abnormally delayed (dally) gene: a putative integral membrane proteoglycan required for cell division patterning during postembryonic development of the nervous system in Drosophila.

    PubMed

    Nakato, H; Futch, T A; Selleck, S B

    1995-11-01

    We have devised a genetic screen to obtain mutants affecting cell division patterning in the developing central nervous system of Drosophila. The division abnormally delayed (dally) locus was identified using a combination of "enhancer trap" and behavioral screening methods. The ordered cell cycle progression of lamina precursor cells, which generate synaptic target neurons for photoreceptors, is disrupted in dally mutants. The first of two lamina precursor cell divisions shows a delayed entry into mitosis. The second division, one that is triggered by an intercellular signal from photoreceptor axons, fails to take place. Similar to lamina precursors, cells that generate the ommatidia of the adult eye show two synchronized divisions found along the morphogenetic furrow in the eye disc and the first division cycle in dally mutants displays a delayed progression into M phase like that found in the first lamina precursor cell division. dally mutations also affect viability and produce morphological defects in several adult tissues, including the eye, antenna, wing and genitalia. Sequencing of a dally cDNA reveals a potential open reading frame of 626 amino acids with homology to a family of Glypican-related integral membrane proteoglycans. These heparan sulfate-containing proteins are attached to the external leaflet of the plasma membrane via a glycosylphosphatidylinositol linkage. Heparan sulfate proteoglycans may serve as co-receptors for a variety of secreted proteins including fibroblast growth factor, vascular endothelial growth factor, hepatocyte growth factor and members of the Wnt, TGF-beta and Hedgehog families. The cell division defects found in dally mutants implicate the Glypican group of integral membrane proteoglycans in the control of cell division during development.

  3. Analogies Solving by Individuals with and without Intellectual Disability: Different Cognitive Patterns as Indicated by Eye Movements

    ERIC Educational Resources Information Center

    Vakil, Eli; Lifshitz, Hefziba; Tzuriel, David; Weiss, Izhak; Arzuoan, Yossi

    2011-01-01

    Eighteen adults with intellectual disability (ID) and 20 children with typical development (TD) matched for cognitive level, participated in this study. Participants solved perceptual and conceptual analogies (from the Conceptual and Perceptual Analogical Modifiability Test-CPAM) while having their eye movements monitored. As predicted, the…

  4. The Reliability of Classification Decisions for the Furtado-Gallagher Computerized Observational Movement Pattern Assessment System--FG-COMPASS

    ERIC Educational Resources Information Center

    Furtado, Ovande, Jr.; Gallagher, Jere D.

    2012-01-01

    Mastery of fundamental movement skills (FMS) is an important factor in preventing weight gain and increasing physical activity. To master FMS, performance evaluation is necessary. In this study, we investigated the reliability of a new observational assessment tool. In Phase I, 110 video clips of children performing five locomotor, and six…

  5. Space-Use Patterns of the Asiatic Wild Ass (Equus hemionus): Complementary Insights from Displacement, Recursion Movement and Habitat Selection Analyses

    PubMed Central

    Giotto, Nina; Gerard, Jean-François; Ziv, Alon; Bouskila, Amos; Bar-David, Shirli

    2015-01-01

    The way in which animals move and use the landscape is influenced by the spatial distribution of resources, and is of importance when considering species conservation. We aimed at exploring how landscape-related factors affect a large herbivore’s space-use patterns by using a combined approach, integrating movement (displacement and recursions) and habitat selection analyses. We studied the endangered Asiatic wild ass (Equus hemionus) in the Negev Desert, Israel, using GPS monitoring and direct observation. We found that the main landscape-related factors affecting the species’ space-use patterns, on a daily and seasonal basis, were vegetation cover, water sources and topography. Two main habitat types were selected: high-elevation sites during the day (specific microclimate: windy on warm summer days) and streambed surroundings during the night (coupled with high vegetation when the animals were active in summer). Distribution of recursion times (duration between visits) revealed a 24-hour periodicity, a pattern that could be widespread among large herbivores. Characterizing frequently revisited sites suggested that recursion movements were mainly driven by a few landscape features (water sources, vegetation patches, high-elevation points), but also by social factors, such as territoriality, which should be further explored. This study provided complementary insights into the space-use patterns of E. hemionus. Understanding of the species’ space-use patterns, at both large and fine spatial scale, is required for developing appropriate conservation protocols. Our approach could be further applied for studying the space-use patterns of other species in heterogeneous landscapes. PMID:26630393

  6. Space-Use Patterns of the Asiatic Wild Ass (Equus hemionus): Complementary Insights from Displacement, Recursion Movement and Habitat Selection Analyses.

    PubMed

    Giotto, Nina; Gerard, Jean-François; Ziv, Alon; Bouskila, Amos; Bar-David, Shirli

    2015-01-01

    The way in which animals move and use the landscape is influenced by the spatial distribution of resources, and is of importance when considering species conservation. We aimed at exploring how landscape-related factors affect a large herbivore's space-use patterns by using a combined approach, integrating movement (displacement and recursions) and habitat selection analyses. We studied the endangered Asiatic wild ass (Equus hemionus) in the Negev Desert, Israel, using GPS monitoring and direct observation. We found that the main landscape-related factors affecting the species' space-use patterns, on a daily and seasonal basis, were vegetation cover, water sources and topography. Two main habitat types were selected: high-elevation sites during the day (specific microclimate: windy on warm summer days) and streambed surroundings during the night (coupled with high vegetation when the animals were active in summer). Distribution of recursion times (duration between visits) revealed a 24-hour periodicity, a pattern that could be widespread among large herbivores. Characterizing frequently revisited sites suggested that recursion movements were mainly driven by a few landscape features (water sources, vegetation patches, high-elevation points), but also by social factors, such as territoriality, which should be further explored. This study provided complementary insights into the space-use patterns of E. hemionus. Understanding of the species' space-use patterns, at both large and fine spatial scale, is required for developing appropriate conservation protocols. Our approach could be further applied for studying the space-use patterns of other species in heterogeneous landscapes. PMID:26630393

  7. Automatically Characterizing Sensory-Motor Patterns Underlying Reach-to-Grasp Movements on a Physical Depth Inversion Illusion.

    PubMed

    Nguyen, Jillian; Majmudar, Ushma V; Ravaliya, Jay H; Papathomas, Thomas V; Torres, Elizabeth B

    2015-01-01

    Recently, movement variability has been of great interest to motor control physiologists as it constitutes a physical, quantifiable form of sensory feedback to aid in planning, updating, and executing complex actions. In marked contrast, the psychological and psychiatric arenas mainly rely on verbal descriptions and interpretations of behavior via observation. Consequently, a large gap exists between the body's manifestations of mental states and their descriptions, creating a disembodied approach in the psychological and neural sciences: contributions of the peripheral nervous system to central control, executive functions, and decision-making processes are poorly understood. How do we shift from a psychological, theorizing approach to characterize complex behaviors more objectively? We introduce a novel, objective, statistical framework, and visuomotor control paradigm to help characterize the stochastic signatures of minute fluctuations in overt movements during a visuomotor task. We also quantify a new class of covert movements that spontaneously occur without instruction. These are largely beneath awareness, but inevitably present in all behaviors. The inclusion of these motions in our analyses introduces a new paradigm in sensory-motor integration. As it turns out, these movements, often overlooked as motor noise, contain valuable information that contributes to the emergence of different kinesthetic percepts. We apply these new methods to help better understand perception-action loops. To investigate how perceptual inputs affect reach behavior, we use a depth inversion illusion (DII): the same physical stimulus produces two distinct depth percepts that are nearly orthogonal, enabling a robust comparison of competing percepts. We find that the moment-by-moment empirically estimated motor output variability can inform us of the participants' perceptual states, detecting physiologically relevant signals from the peripheral nervous system that reveal internal

  8. Automatically Characterizing Sensory-Motor Patterns Underlying Reach-to-Grasp Movements on a Physical Depth Inversion Illusion

    PubMed Central

    Nguyen, Jillian; Majmudar, Ushma V.; Ravaliya, Jay H.; Papathomas, Thomas V.; Torres, Elizabeth B.

    2016-01-01

    Recently, movement variability has been of great interest to motor control physiologists as it constitutes a physical, quantifiable form of sensory feedback to aid in planning, updating, and executing complex actions. In marked contrast, the psychological and psychiatric arenas mainly rely on verbal descriptions and interpretations of behavior via observation. Consequently, a large gap exists between the body's manifestations of mental states and their descriptions, creating a disembodied approach in the psychological and neural sciences: contributions of the peripheral nervous system to central control, executive functions, and decision-making processes are poorly understood. How do we shift from a psychological, theorizing approach to characterize complex behaviors more objectively? We introduce a novel, objective, statistical framework, and visuomotor control paradigm to help characterize the stochastic signatures of minute fluctuations in overt movements during a visuomotor task. We also quantify a new class of covert movements that spontaneously occur without instruction. These are largely beneath awareness, but inevitably present in all behaviors. The inclusion of these motions in our analyses introduces a new paradigm in sensory-motor integration. As it turns out, these movements, often overlooked as motor noise, contain valuable information that contributes to the emergence of different kinesthetic percepts. We apply these new methods to help better understand perception-action loops. To investigate how perceptual inputs affect reach behavior, we use a depth inversion illusion (DII): the same physical stimulus produces two distinct depth percepts that are nearly orthogonal, enabling a robust comparison of competing percepts. We find that the moment-by-moment empirically estimated motor output variability can inform us of the participants' perceptual states, detecting physiologically relevant signals from the peripheral nervous system that reveal internal

  9. Modulations of eye movement patterns by spatial filtering during the learning and testing phases of an old/new face recognition task.

    PubMed

    Lemieux, Chantal L; Collin, Charles A; Nelson, Elizabeth A

    2015-02-01

    In two experiments, we examined the effects of varying the spatial frequency (SF) content of face images on eye movements during the learning and testing phases of an old/new recognition task. At both learning and testing, participants were presented with face stimuli band-pass filtered to 11 different SF bands, as well as an unfiltered baseline condition. We found that eye movements varied significantly as a function of SF. Specifically, the frequency of transitions between facial features showed a band-pass pattern, with more transitions for middle-band faces (≈5-20 cycles/face) than for low-band (≈<5 cpf) or high-band (≈>20 cpf) ones. These findings were similar for the learning and testing phases. The distributions of transitions across facial features were similar for the middle-band, high-band, and unfiltered faces, showing a concentration on the eyes and mouth; conversely, low-band faces elicited mostly transitions involving the nose and nasion. The eye movement patterns elicited by low, middle, and high bands are similar to those previous researchers have suggested reflect holistic, configural, and featural processing, respectively. More generally, our results are compatible with the hypotheses that eye movements are functional, and that the visual system makes flexible use of visuospatial information in face processing. Finally, our finding that only middle spatial frequencies yielded the same number and distribution of fixations as unfiltered faces adds more evidence to the idea that these frequencies are especially important for face recognition, and reveals a possible mediator for the superior performance that they elicit.

  10. Diffusion Tensor Imaging in Movement Disorders: Review of Major Patterns and Correlation with Normal Brainstem/cerebellar White Matter.

    PubMed

    Reimão, S; Morgado, C; Neto, L; Ferreira, J; Coelho, M; Rosa, M; Campos, J

    2011-05-15

    The authors reviewed the diffusion tensor imaging (DTI) and tractography (DTT) of the normal brainstem and cerebellar white matter in normal volunteers, correlating it with structural magnetic resonance (MR) imaging and DTI data obtained in patients evaluated in our institution with movement disorders, including multisystem atrophy (MSA), spinocerebellar ataxia (SCA), progressive supra-nuclear palsy (PSP) and idiopathic Parkinson's disease (PD). DTI and tractography data demonstrated major white-matter fibers within the brain stem and cerebellum, including cortico-spinal tracts, transverse pontine fibers, medial lemniscus and cerebellar peduncles. Visualization of selective degeneration of these individual fibre tracts with DTI, in our cases, added qualitative data to the differential diagnosis of movement disorders. PMID:24059605

  11. Thinking like a duck: fall lake use and movement patterns of juvenile ring-necked ducks before migration.

    PubMed

    Roy, Charlotte L; Fieberg, John; Scharenbroich, Christopher; Herwig, Christine M

    2014-01-01

    The post-fledging period is one of the least studied portions of the annual cycle in waterfowl. Yet, recruitment into the breeding population requires that young birds have sufficient resources to survive this period. We used radio-telemetry and generalized estimating equations to examine support for four hypotheses regarding the drivers of landscape scale habitat use and movements made by juvenile ring-necked ducks between the pre-fledging period and departure for migration. Our response variables included the probability of movement, distances moved, and use of different lake types: brood-rearing lakes, staging lakes, and lakes with low potential for disturbance. Birds increased their use of staging areas and lakes with low potential for disturbance (i.e., without houses or boat accesses, >100 m from roads, or big lakes with areas where birds could sit undisturbed) throughout the fall, but these changes began before the start of the hunting season and their trajectory was not changed by the onset of hunting. Males and females moved similar distances and had similar probabilities of movements each week. However, females were more likely than males to use brood-rearing lakes later in the fall. Our findings suggest juvenile ring-necked ducks require different lake types throughout the fall, and managing solely for breeding habitat will be insufficient for meeting needs during the post-fledging period. Maintaining areas with low potential for disturbance and areas suitable for staging will ensure that ring-necked ducks have access to habitat throughout the fall.

  12. Thinking Like a Duck: Fall Lake Use and Movement Patterns of Juvenile Ring-Necked Ducks before Migration

    PubMed Central

    Roy, Charlotte L.; Fieberg, John; Scharenbroich, Christopher; Herwig, Christine M.

    2014-01-01

    The post-fledging period is one of the least studied portions of the annual cycle in waterfowl. Yet, recruitment into the breeding population requires that young birds have sufficient resources to survive this period. We used radio-telemetry and generalized estimating equations to examine support for four hypotheses regarding the drivers of landscape scale habitat use and movements made by juvenile ring-necked ducks between the pre-fledging period and departure for migration. Our response variables included the probability of movement, distances moved, and use of different lake types: brood-rearing lakes, staging lakes, and lakes with low potential for disturbance. Birds increased their use of staging areas and lakes with low potential for disturbance (i.e., without houses or boat accesses, >100 m from roads, or big lakes with areas where birds could sit undisturbed) throughout the fall, but these changes began before the start of the hunting season and their trajectory was not changed by the onset of hunting. Males and females moved similar distances and had similar probabilities of movements each week. However, females were more likely than males to use brood-rearing lakes later in the fall. Our findings suggest juvenile ring-necked ducks require different lake types throughout the fall, and managing solely for breeding habitat will be insufficient for meeting needs during the post-fledging period. Maintaining areas with low potential for disturbance and areas suitable for staging will ensure that ring-necked ducks have access to habitat throughout the fall. PMID:24551123

  13. Horizontal movements, migration patterns, and population structure of whale sharks in the Gulf of Mexico and northwestern Caribbean sea.

    PubMed

    Hueter, Robert E; Tyminski, John P; de la Parra, Rafael

    2013-01-01

    Whale sharks, Rhincodon typus, aggregate by the hundreds in a summer feeding area off the northeastern Yucatan Peninsula, Mexico, where the Gulf of Mexico meets the Caribbean Sea. The aggregation remains in the nutrient-rich waters off Isla Holbox, Isla Contoy and Isla Mujeres, Quintana Roo for several months in the summer and then dissipates between August and October. Little has been known about where these sharks come from or migrate to after they disperse. From 2003-2012, we used conventional visual tags, photo-identification, and satellite tags to characterize the basic population structure and large-scale horizontal movements of whale sharks that come to this feeding area off Mexico. The aggregation comprised sharks ranging 2.5-10.0 m in total length and included juveniles, subadults, and adults of both sexes, with a male-biased sex ratio (72%). Individual sharks remained in the area for an estimated mean duration of 24-33 days with maximum residency up to about 6 months as determined by photo-identification. After leaving the feeding area the sharks showed horizontal movements in multiple directions throughout the Gulf of Mexico basin, the northwestern Caribbean Sea, and the Straits of Florida. Returns of individual sharks to the Quintana Roo feeding area in subsequent years were common, with some animals returning for six consecutive years. One female shark with an estimated total length of 7.5 m moved at least 7,213 km in 150 days, traveling through the northern Caribbean Sea and across the equator to the South Atlantic Ocean where her satellite tag popped up near the Mid-Atlantic Ridge. We hypothesize this journey to the open waters of the Mid-Atlantic was for reproductive purposes but alternative explanations are considered. The broad movements of whale sharks across multiple political boundaries corroborates genetics data supporting gene flow between geographically distinct areas and underscores the need for management and conservation strategies for

  14. Long-distance movement of Cauliflower mosaic virus and host defence responses in Arabidopsis follow a predictable pattern that is determined by the leaf orthostichy.

    PubMed

    Roberts, Karen; Love, Andrew J; Laval, Valérie; Laird, Janet; Tomos, A Deri; Hooks, Mark A; Milner, Joel J

    2007-01-01

    Long-distance virus transport takes place through the vascular system and is dependent on the movement of photoassimilates. Here, patterns of symptom development, virus movement and gene expression were analysed in Arabidopsis following inoculation with Cauliflower mosaic virus (CaMV) on a single leaf. Virus accumulation and expression of markers for the salicylic acid (SA) and ethylene/jasmonate (Et/JA) defence pathways, PR-1 and PDF1.2, were analysed on a leaf-by-leaf basis by real-time reverse transcription polymerase chain reaction (qRT-PCR). Virus spread followed a strictly defined pattern identical to that of a source-sink relationship. This was exploited to study differences between local and systemic defence responses in a developmental and spatial manner. In infected plants, PR-1 transcripts accumulated primarily but not exclusively in leaves with a direct vascular connection to the inoculated leaf. Abundances fell significantly as virus accumulated. By contrast, PDF1.2 transcripts were significantly lower than in controls in all leaves at early stages of infection, but recovered as virus accumulated. Virus and PR-1 transcript abundances are negatively correlated, and SA- and Et/JA-mediated signalling of gene expression occurs independently of the presence of virus. Although SA-dependent signalling responses were mainly linked to the orthostichy, Et/JA-dependent responses were independent of vascular connections. PMID:17688586

  15. Strontium isotope investigation of ungulate movement patterns on the Pleistocene Paleo-Agulhas Plain of the Greater Cape Floristic Region, South Africa

    NASA Astrophysics Data System (ADS)

    Copeland, Sandi R.; Cawthra, Hayley C.; Fisher, Erich C.; Lee-Thorp, Julia A.; Cowling, Richard M.; le Roux, Petrus J.; Hodgkins, Jamie; Marean, Curtis W.

    2016-06-01

    Middle Stone Age sites located within the Greater Cape Floristic Region on the South African southern coast have material culture with early evidence for key modern human behaviors such as projectile weaponry, large animal hunting, and symbolic behavior. In order to interpret how and why these changes evolved, it is necessary to understand their ecological context as it has direct relevance to foraging behavior. During periods of lowered sea level, a largely flat and vast expanse of land existed south of the modern coastline, but it is now submerged by higher sea levels. This exposed area, the Paleo-Agulhas Plain, likely created an ecological context unlike anything in the region today, as evidenced by fossil assemblages dominated by migratory ungulates. One hypothesis is that the Paleo-Agulhas Plain supported a migration ecosystem of large grazers driven by summer rainfall, producing palatable forage during summer in the east, and winter rainfall, producing palatable forage during winter in the west. Alternatively, ungulates may have been moving from the coastal plain in the south to the interior north of the Cape Fold Mountains, as observed for elephants in historic times. In this study, we assess ungulate movement patterns with inter- and intra-tooth enamel samples for strontium isotopes in fossil fauna from Pinnacle Point sites PP13B and PP30. To accomplish our goals we created a bioavailable 87Sr/86Sr isoscape for the region by collecting plants at 171 sampling sites and developing a geospatial model. The strontium isotope results indicate that ungulates spent most of their time on the Paleo-Agulhas Plain and avoided dissected plain, foothill, and mountain habitats located more than about 15 km north of the modern coastline. The results clearly exclude a north-south (coastal-interior) movement or migration pattern, and cannot falsify the east-west movements hypothesized in the south coast migration ecosystem hypothesis.

  16. Patterns of pulmonary perfusion scans in normal subjects. IV. The prevalence of abnormal scans in smokers 30 to 49 years of age

    SciTech Connect

    Fedullo, P.F.; Kapitan, K.S.; Brewer, N.S.; Ashburn, W.L.; Hartman, M.T.; Moser, K.M.

    1989-05-01

    The usefulness of ventilation-perfusion scans in the diagnosis of pulmonary embolism is limited by the wide range of pulmonary diseases that are associated with abnormal scans, and by the largely undetermined prevalence of abnormal scans in persons without cardiopulmonary disease. In prior studies, we found perfusion defects to be rarely present in young persons and in older nonsmokers. To determine if normal older smokers have a higher prevalence of abnormal ventilation and perfusion scans, we performed six-view /sup 99m/Tc perfusion (Q) scans and /sup 133/Xe ventilation (V) scans in 40 subjects 30 to 49 yr of age who had no known cardiopulmonary disease. Each subject had undergone a history, physical examination, electrocardiogram, spirometry, and posteroanterior chest roentgenogram prior to scanning. All V and Q scans were interpreted blindly and independently by two experienced readers. No subject demonstrated a lobar or segmental defect on two views. One subject had a matched subsegmental defect, and one subject had delayed washout from a subsegmental area of the right upper lobe during V scanning, with a normal Q scan. We conclude that abnormal V and Q scans are uncommon among normal smokers 30 to 49 yr of age.

  17. Horizontal Movements, Migration Patterns, and Population Structure of Whale Sharks in the Gulf of Mexico and Northwestern Caribbean Sea

    PubMed Central

    Hueter, Robert E.; Tyminski, John P.; de la Parra, Rafael

    2013-01-01

    Whale sharks, Rhincodon typus, aggregate by the hundreds in a summer feeding area off the northeastern Yucatan Peninsula, Mexico, where the Gulf of Mexico meets the Caribbean Sea. The aggregation remains in the nutrient-rich waters off Isla Holbox, Isla Contoy and Isla Mujeres, Quintana Roo for several months in the summer and then dissipates between August and October. Little has been known about where these sharks come from or migrate to after they disperse. From 2003–2012, we used conventional visual tags, photo-identification, and satellite tags to characterize the basic population structure and large-scale horizontal movements of whale sharks that come to this feeding area off Mexico. The aggregation comprised sharks ranging 2.5–10.0 m in total length and included juveniles, subadults, and adults of both sexes, with a male-biased sex ratio (72%). Individual sharks remained in the area for an estimated mean duration of 24–33 days with maximum residency up to about 6 months as determined by photo-identification. After leaving the feeding area the sharks showed horizontal movements in multiple directions throughout the Gulf of Mexico basin, the northwestern Caribbean Sea, and the Straits of Florida. Returns of individual sharks to the Quintana Roo feeding area in subsequent years were common, with some animals returning for six consecutive years. One female shark with an estimated total length of 7.5 m moved at least 7,213 km in 150 days, traveling through the northern Caribbean Sea and across the equator to the South Atlantic Ocean where her satellite tag popped up near the Mid-Atlantic Ridge. We hypothesize this journey to the open waters of the Mid-Atlantic was for reproductive purposes but alternative explanations are considered. The broad movements of whale sharks across multiple political boundaries corroborates genetics data supporting gene flow between geographically distinct areas and underscores the need for management and conservation strategies

  18. Computational cell model based on autonomous cell movement regulated by cell-cell signalling successfully recapitulates the "inside and outside" pattern of cell sorting

    PubMed Central

    Maeda, Takuya T; Ajioka, Itsuki; Nakajima, Kazunori

    2007-01-01

    Background Development of multicellular organisms proceeds from a single fertilized egg as the combined effect of countless numbers of cellular interactions among highly dynamic cells. Since at least a reminiscent pattern of morphogenesis can be recapitulated in a reproducible manner in reaggregation cultures of dissociated embryonic cells, which is known as cell sorting, the cells themselves must possess some autonomous cell behaviors that assure specific and reproducible self-organization. Understanding of this self-organized dynamics of heterogeneous cell population seems to require some novel approaches so that the approaches bridge a gap between molecular events and morphogenesis in developmental and cell biology. A conceptual cell model in a computer may answer that purpose. We constructed a dynamical cell model based on autonomous cell behaviors, including cell shape, growth, division, adhesion, transformation, and motility as well as cell-cell signaling. The model gives some insights about what cellular behaviors make an appropriate global pattern of the cell population. Results We applied the model to "inside and outside" pattern of cell-sorting, in which two different embryonic cell types within a randomly mixed aggregate are sorted so that one cell type tends to gather in the central region of the aggregate and the other cell type surrounds the first cell type. Our model can modify the above cell behaviors by varying parameters related to them. We explored various parameter sets with which the "inside and outside" pattern could be achieved. The simulation results suggested that direction of cell movement responding to its neighborhood and the cell's mobility are important for this specific rearrangement. Conclusion We constructed an in silico cell model that mimics autonomous cell behaviors and applied it to cell sorting, which is a simple and appropriate phenomenon exhibiting self-organization of cell population. The model could predict directional cell

  19. NUP98/JARID1A is a novel recurrent abnormality in pediatric acute megakaryoblastic leukemia with a distinct HOX gene expression pattern.

    PubMed

    de Rooij, J D E; Hollink, I H I M; Arentsen-Peters, S T C J M; van Galen, J F; Berna Beverloo, H; Baruchel, A; Trka, J; Reinhardt, D; Sonneveld, E; Zimmermann, M; Alonzo, T A; Pieters, R; Meshinchi, S; van den Heuvel-Eibrink, M M; Zwaan, C Michel

    2013-12-01

    Cytogenetic abnormalities and early response to treatment are the main prognostic factors in acute myeloid leukemia (AML). Recently, NUP98/NSD1 (t(5; 11)(q35; p15)), a cytogenetically cryptic fusion, was described as recurrent event in AML, characterized by dismal prognosis and HOXA/B gene overexpression. Using split-signal fluorescence in situ hybridization, other NUP98-rearranged pediatric AML cases were identified, including several acute megakaryoblastic leukemia (AMKL) cases with a cytogenetically cryptic fusion of NUP98 to JARID1A (t(11;15)(p15;q35)). In this study we screened 105 pediatric AMKL cases to analyze the frequency of NUP98/JARID1A and other recurrent genetic abnormalities. NUP98/JARID1A was identified in 11/105 patients (10.5%). Other abnormalities consisted of RBM15/MKL1 (n=16), CBFA2T3/GLIS2 (n=13) and MLL-rearrangements (n=13). Comparing NUP98/JARID1A-positive patients with other pediatric AMKL patients, no significant differences in sex, age and white blood cell count were found. NUP98/JARID1A was not an independent prognostic factor for 5-year overall (probability of overall survival (pOS)) or event-free survival (probability of event-free survival (pEFS)), although the 5-year pOS for the entire AMKL cohort was poor (42 ± 6%). Cases with RBM15/MLK1 fared significantly better in terms of pOS and pEFS, although this was not independent from other risk factors in multivariate analysis. NUP98/JARID1A cases were characterized by HOXA/B gene overexpression, which is a potential druggable pathway. In conclusion, NUP98/JARID1A is a novel recurrent genetic abnormality in pediatric AMKL.

  20. Correlation dimension of collective versus individual pedestrian movement patterns in crowd-quakes: A case-study

    NASA Astrophysics Data System (ADS)

    Lian, Liping; Song, Weiguo; Ma, Jian; Telesca, Luciano

    2016-06-01

    Video recording right before the Love Parade, Duisburg (Germany) crowd-quake, occurred on 24 July 2010, has been analysed in order to investigate the spatial properties of the crowd (collective case) and those of the single pedestrians in the crowd (individual case). The Grassberger-Procaccia correlation dimension, well known to be able to distinguish patterns in spatial point processes, was used. Our results for this case-study reveal that crowd and single pedestrians are characterized by different spatial behaviour: the whole crowd behaves as a quasi-homogeneous spatial point process through time, with an averaged correlation dimension of about 1.92; while the single pedestrians show a quite large variation of correlation dimensions indicating different spatial patterns, ranging from clustered to quasi-homogeneous.

  1. Identification of the Plant for Upright Stance in Humans: Multiple Movement Patterns From a Single Neural Strategy

    PubMed Central

    Kiemel, Tim; Elahi, Alexander J.; Jeka, John J.

    2008-01-01

    We determined properties of the plant during human upright stance using a closed-loop system identification method originally applied to human postural control by another group. To identify the plant, which was operationally defined as the mapping from muscle activation (rectified EMG signals) to body segment angles, we rotated the visual scene about the axis through the subject's ankles using a sum-of-sines stimulus signal. Because EMG signals from ankle muscles and from hip and lower trunk muscles showed similar responses to the visual perturbation across frequency, we combined EMG signals from all recorded muscles into a single plant input. Body kinematics were described by the trunk and leg angles in the sagittal plane. The phase responses of both angles to visual scene angle were similar at low frequencies and approached a difference of ∼150° at higher frequencies. Therefore we considered leg and trunk angles as separate plant outputs. We modeled the plant with a two-joint (ankle and hip) model of the body, a second-order low-pass filter from EMG activity to active joint torques, and intrinsic stiffness and damping at both joints. The results indicated that the in-phase (ankle) pattern was neurally generated, whereas the out-of-phase pattern was caused by plant dynamics. Thus a single neural strategy leads to multiple kinematic patterns. Moreover, estimated intrinsic stiffness in the model was insufficient to stabilize the plant. PMID:18829854

  2. Age-Related Differences in Vehicle Control and Eye Movement Patterns at Intersections: Older and Middle-Aged Drivers

    PubMed Central

    Yamani, Yusuke; Horrey, William J.; Liang, Yulan; Fisher, Donald L.

    2016-01-01

    Older drivers are at increased risk of intersection crashes. Previous work found that older drivers execute less frequent glances for detecting potential threats at intersections than middle-aged drivers. Yet, earlier work has also shown that an active training program doubled the frequency of these glances among older drivers, suggesting that these effects are not necessarily due to age-related functional declines. In light of findings, the current study sought to explore the ability of older drivers to coordinate their head and eye movements while simultaneously steering the vehicle as well as their glance behavior at intersections. In a driving simulator, older (M = 76 yrs) and middle-aged (M = 58 yrs) drivers completed different driving tasks: (1) travelling straight on a highway while scanning for peripheral information (a visual search task) and (2) navigating intersections with areas potential hazard. The results replicate that the older drivers did not execute glances for potential threats to the sides when turning at intersections as frequently as the middle-aged drivers. Furthermore, the results demonstrate costs of performing two concurrent tasks, highway driving and visual search task on the side displays: the older drivers performed more poorly on the visual search task and needed to correct their steering positions more compared to the middle-aged counterparts. The findings are consistent with the predictions and discussed in terms of a decoupling hypothesis, providing an account for the effects of the active training program. PMID:27736887

  3. Quantifying patterns of dynamics in eye movement to measure goodness in organization of design elements in interior architecture

    NASA Astrophysics Data System (ADS)

    Mirkia, Hasti; Sangari, Arash; Nelson, Mark; Assadi, Amir H.

    2013-03-01

    Architecture brings together diverse elements to enhance the observer's measure of esthetics and the convenience of functionality. Architects often conceptualize synthesis of design elements to invoke the observer's sense of harmony and positive affect. How does an observer's brain respond to harmony of design in interior spaces? One implicit consideration by architects is the role of guided visual attention by observers while navigating indoors. Prior visual experience of natural scenes provides the perceptual basis for Gestalt of design elements. In contrast, Gestalt of organization in design varies according to the architect's decision. We outline a quantitative theory to measure the success in utilizing the observer's psychological factors to achieve the desired positive affect. We outline a unified framework for perception of geometry and motion in interior spaces, which integrates affective and cognitive aspects of human vision in the context of anthropocentric interior design. The affective criteria are derived from contemporary theories of interior design. Our contribution is to demonstrate that the neural computations in an observer's eye movement could be used to elucidate harmony in perception of form, space and motion, thus a measure of goodness of interior design. Through mathematical modeling, we argue the plausibility of the relevant hypotheses.

  4. Spectral feature extraction of EEG signals and pattern recognition during mental tasks of 2-D cursor movements for BCI using SVM and ANN.

    PubMed

    Bascil, M Serdar; Tesneli, Ahmet Y; Temurtas, Feyzullah

    2016-09-01

    Brain computer interface (BCI) is a new communication way between man and machine. It identifies mental task patterns stored in electroencephalogram (EEG). So, it extracts brain electrical activities recorded by EEG and transforms them machine control commands. The main goal of BCI is to make available assistive environmental devices for paralyzed people such as computers and makes their life easier. This study deals with feature extraction and mental task pattern recognition on 2-D cursor control from EEG as offline analysis approach. The hemispherical power density changes are computed and compared on alpha-beta frequency bands with only mental imagination of cursor movements. First of all, power spectral density (PSD) features of EEG signals are extracted and high dimensional data reduced by principle component analysis (PCA) and independent component analysis (ICA) which are statistical algorithms. In the last stage, all features are classified with two types of support vector machine (SVM) which are linear and least squares (LS-SVM) and three different artificial neural network (ANN) structures which are learning vector quantization (LVQ), multilayer neural network (MLNN) and probabilistic neural network (PNN) and mental task patterns are successfully identified via k-fold cross validation technique. PMID:27376723

  5. Spectral feature extraction of EEG signals and pattern recognition during mental tasks of 2-D cursor movements for BCI using SVM and ANN.

    PubMed

    Bascil, M Serdar; Tesneli, Ahmet Y; Temurtas, Feyzullah

    2016-09-01

    Brain computer interface (BCI) is a new communication way between man and machine. It identifies mental task patterns stored in electroencephalogram (EEG). So, it extracts brain electrical activities recorded by EEG and transforms them machine control commands. The main goal of BCI is to make available assistive environmental devices for paralyzed people such as computers and makes their life easier. This study deals with feature extraction and mental task pattern recognition on 2-D cursor control from EEG as offline analysis approach. The hemispherical power density changes are computed and compared on alpha-beta frequency bands with only mental imagination of cursor movements. First of all, power spectral density (PSD) features of EEG signals are extracted and high dimensional data reduced by principle component analysis (PCA) and independent component analysis (ICA) which are statistical algorithms. In the last stage, all features are classified with two types of support vector machine (SVM) which are linear and least squares (LS-SVM) and three different artificial neural network (ANN) structures which are learning vector quantization (LVQ), multilayer neural network (MLNN) and probabilistic neural network (PNN) and mental task patterns are successfully identified via k-fold cross validation technique.

  6. Properties of saccade-related neurons in the cat superior colliculus: patterns of movement fields and discharge timing.

    PubMed

    Kang, I; Lee, C

    2000-03-01

    The discharge characteristics of saccade-related neurons in the superior colliculi (SC) of trained cats were investigated in order to understand the involvement of the SC in dynamic control of saccades. In particular, two aspects of saccade-related collicular activity in relation to visually guided saccades were quantitatively analyzed: the bounded pattern of amplitude tuning and the timing of neural activity in relation to saccade offset. In order to determine whether the amplitude tuning of SC cells is bounded or unbounded, we characterized it with a quantitative index, the unbounded-field (UF) index. Analysis of the characteristics of the distribution of this index, including the absence of unbounded fields for cells within the central 10 degrees, suggested that all cells form a single class and that apparent unbounded amplitude tuning is an artifact occurring when the range of gaze shift is truncated by restraining the head. This interpretation is supported by the results of a computer simulation based on truncation of gaze-shift range that closely replicated the experimental data. Analyses of relative location of peak motor activity in the spatial and temporal dimensions revealed that the peak discharge was more closely linked to the midpoint of the saccade than to the offset of saccade, regardless of the pattern of amplitude tuning. These results do not support the proposal advanced by the moving-hill hypothesis: the bounded pattern of amplitude tuning is inconsistent with rostral migration of the activity locus during execution of a saccade, and the relative location of the peak motor activity is inconsistent with the idea that the SC activity encodes dynamic motor error (the difference between desired and current gaze directions).

  7. Influence of different substrate moistures on wood consumption and movement patterns of Microcerotermes crassus and Coptotermes gestroi (Blattodea: Termitidae, Rhinotermitidae).

    PubMed

    Wong, Nellie; Lee, Chow-Yang

    2010-04-01

    Moisture is an important physical factor for the survival of termites. The effects of different moisture levels (0, 5, 10, 15, 20, and 25%) of a sand substrate on the behavior of laboratory groups of Microcerotermes crassus Snyder and Coptotermes gestroi (Wasmann) (Blattodea: Termitidae: Rhinotermitidae) were evaluated. Moisture content of sand affected wood consumption and influenced termite distribution across a moisture gradient for M. crassus. Changing the moisture parameters affected the location preference of C. gestroi, but the effect on wood consumption was not significant. Nonetheless, M. crassus and C. gestroi showed a similar distribution pattern of association with particular moisture levels.

  8. Demography and movement patterns of leopard sharks (Triakis semifasciata) aggregating near the head of a submarine canyon along the open coast of southern California, USA

    USGS Publications Warehouse

    Nosal, D.C.; Cartamil, D.C.; Long, J.W.; Luhrmann, M.; Wegner, N.C.; Graham, J.B.

    2013-01-01

    The demography, spatial distribution, and movement patterns of leopard sharks (Triakis semifasciata) aggregating near the head of a submarine canyon in La Jolla, California, USA, were investigated to resolve the causal explanations for this and similar shark aggregations. All sharks sampled from the aggregation site (n=140) were sexually mature and 97.1 % were female. Aerial photographs taken during tethered balloon surveys revealed high densities of milling sharks of up to 5470 sharks ha-1. Eight sharks were each tagged with a continuous acoustic transmitter and manually tracked without interruption for up to 48 h. Sharks exhibited strong site-fidelity and were generally confined to a divergence (shadow) zone of low wave energy, which results from wave refraction over the steep bathymetric contours of the submarine canyon. Within this divergence zone, the movements of sharks were strongly localized over the seismically active Rose Canyon Fault. Tracked sharks spent most of their time in shallow water (≤2 m for 71.0 % and ≤10 m for 95.9 % of time), with some dispersing to deeper (max: 53.9 m) and cooler (min: 12.7 °C) water after sunset, subsequently returning by sunrise. These findings suggest multiple functions of this aggregation and that the mechanism controlling its formation, maintenance, and dissolution is complex and rooted in the sharks' variable response to numerous confounding environmental factors.

  9. Evaluation of Fish Movements, Migration Patterns, and Population Abundance with Streamwidth PIT Tag Interrogation Systems, Final Report 2002.

    SciTech Connect

    Zydlewski, Gayle; Winter, Christiane; McClanahan, Dee

    2003-02-01

    Two remote Streamwidth PIT tag Interrogation systems (SPIs) were operated continuously for over one year to test the feasibility of these systems for generating movement, migration, survival and smolt production estimates for salmonids. A total of 1,588 juvenile (< 100 mm FL) naturally produced salmonids (7 coho salmon, 482 cutthroat trout, and 1,099 steelhead) were PIT tagged above the upstream-most SPI (9 sites approximately 1 linear km each) in Fall 2001. Age at tagging for wild caught cutthroat and steelhead was 1 year. SPIs were operating before any PIT tagged fish were released in the creek. Over 390,000 detections were recorded from October 2001 to 31 July 2002. Efficiencies were site dependent, but overall detection efficiency for the creek was 97% with 95% confidence intervals of 91-100%. PIT tag detection efficiency ranged from 55-100% depending on the SPI and varied throughout the year with average efficiencies of 73% and 89%. SPI efficiency of PIT tag detection was not completely dependent on electronics noise levels or environmental conditions. Fish from all tagging locations were detected at the SPIs. Steelhead and cutthroat trout were primarily detected moving in the Spring (April-June) coincident with the anticipated smolt migration. Steelhead were also detected moving past SPIs at lower numbers in the Fall and Winter. Travel time between SPIs (downstream movement) was highly dependent on time of year. Travel time in the Spring was significantly faster (34.4 {+-} 7.0 hours) for all species than during any other time of year (763.1 {+-} 267.0 hours). Steelhead and cutthroat migrating in the Spring were the same age as those that did not migrate in the Spring. Peak of steelhead migration recorded at the two SPIs was 5/11 and 5/12 and the peak in the screw trap was recorded on 5/17. Steelhead smolt production estimates using SPIs (3,802 with 95% confidence intervals of 3,440 - 4,245) was similar to those using more standard screw trap methods

  10. Evaluation of Fish Movements, Migration Patterns and Populations Abundance with Streamwidth PIT Tag Interrogation Systems, Final Report 2002.

    SciTech Connect

    Zydlewski, Gayle B.; Casey, Sean

    2003-02-01

    Two remote Streamwidth PIT tag Interrogation systems (SPIs) were operated continuously for over one year to test the feasibility of these systems for generating movement, migration, survival and smolt production estimates for salmonids. A total of 1,588 juvenile (< 100 mm FL) naturally produced salmonids (7 coho salmon, 482 cutthroat trout, and 1,099 steelhead) were PIT tagged above the upstream-most SPI (9 sites approximately 1 linear km each) in Fall 2001. Age at tagging for wild caught cutthroat and steelhead was 1 year. SPIs were operating before any PIT tagged fish were released in the creek. Over 390,000 detections were recorded from October 2001 to 31 July 2002. Efficiencies were site dependent, but overall detection efficiency for the creek was 97% with 95% confidence intervals of 91-100%. PIT tag detection efficiency ranged from 55-100% depending on the SPI and varied throughout the year with average efficiencies of 73% and 89%. SPI efficiency of PIT tag detection was not completely dependent on electronics noise levels or environmental conditions. Fish from all tagging locations were detected at the SPIs. Steelhead and cutthroat trout were primarily detected moving in the Spring (April-June) coincident with the anticipated smolt migration. Steelhead were also detected moving past SPIs at lower numbers in the Fall and Winter. Travel time between SPIs (downstream movement) was highly dependent on time of year. Travel time in the Spring was significantly faster (34.4 {+-} 7.0 hours) for all species than during any other time of year (763.1 {+-} 267.0 hours). Steelhead and cutthroat migrating in the Spring were the same age as those that did not migrate in the Spring. Peak of steelhead migration recorded at the two SPIs was 5/11 and 5/12 and the peak in the screw trap was recorded on 5/17. Steelhead smolt production estimates using SPIs (3,802 with 95% confidence intervals of 3,440-4,245) was similar to those using more standard screw trap methods

  11. Differential Movement Patterns of Juvenile Tengmalms Owls (Aegolius funereus) during the Post-Fledging Dependence Period in Two Years with Contrasting Prey Abundance

    PubMed Central

    Kouba, Marek; Bartoš, Luděk; Štastný, Karel

    2013-01-01

    Fledgling behaviour and movement patterns throughout the post-fledging dependence period (PFDP), especially in relation to changing environmental conditions, have been rarely studied, despite the fact that this period is recognized as of crucial significance in terms of high mortality of juveniles. The PFDP can extend over quite a protracted period, particularly in birds of prey, and a knowledge of the movement patterns of individuals is fundamental for understanding mechanisms underlying survival, habitat use and dispersion. We radiotracked 39 fledglings of the Tengmalm’s owl (Aegolius funereus) in two years with different availability of prey: 2010 (n = 29) and 2011 (n = 10) and obtained 1455 daily locations. Fledglings reached independence on average in 45 days after fledging in 2010 (n = 22) and 57 days in 2011 (n = 6). Within years, the most important measures influencing the distance moved from the nest box were age of fledglings and number of surviving siblings present. Individual home range size and duration of PFDP in particular were dependent on maximal number of siblings seen outside the nest box. In the season with low prey availability fledglings were observed at greater distances from the nest box than in the year with higher prey availability (mean distance: 350 m in 2010 and 650 m in 2011) and occupied larger home ranges (mean: 30.3 ha in 2010 and 57.7 ha in 2011). The main factor causing these differences between years was probably the different availability of prey in these two years, affecting breeding success and post-fledging survivorship of the Tengmalm’s owls. PMID:23843981

  12. Differential movement patterns of juvenile Tengmalms owls (Aegolius funereus) during the post-fledging dependence period in two years with contrasting prey abundance.

    PubMed

    Kouba, Marek; Bartoš, Luděk; Štastný, Karel

    2013-01-01

    Fledgling behaviour and movement patterns throughout the post-fledging dependence period (PFDP), especially in relation to changing environmental conditions, have been rarely studied, despite the fact that this period is recognized as of crucial significance in terms of high mortality of juveniles. The PFDP can extend over quite a protracted period, particularly in birds of prey, and a knowledge of the movement patterns of individuals is fundamental for understanding mechanisms underlying survival, habitat use and dispersion. We radiotracked 39 fledglings of the Tengmalm's owl (Aegolius funereus) in two years with different availability of prey: 2010 (n = 29) and 2011 (n = 10) and obtained 1455 daily locations. Fledglings reached independence on average in 45 days after fledging in 2010 (n = 22) and 57 days in 2011 (n = 6). Within years, the most important measures influencing the distance moved from the nest box were age of fledglings and number of surviving siblings present. Individual home range size and duration of PFDP in particular were dependent on maximal number of siblings seen outside the nest box. In the season with low prey availability fledglings were observed at greater distances from the nest box than in the year with higher prey availability (mean distance: 350 m in 2010 and 650 m in 2011) and occupied larger home ranges (mean: 30.3 ha in 2010 and 57.7 ha in 2011). The main factor causing these differences between years was probably the different availability of prey in these two years, affecting breeding success and post-fledging survivorship of the Tengmalm's owls. PMID:23843981

  13. Determination of air movement in stored grain as a factor in dynamic dispersion and distribution patterns of gaseous pesticides (fumigants).

    PubMed

    Berck, B

    1975-05-01

    The new research reported herein was motivated by variations in distribution-persistence patterns of fumigant residues (BERCK, 1974). The current developmental program is still underway. In the meantime, measurement of picoliter amounts of SF6 in air by GC equipped with a Ni63 EC detector has been proven useful over an airflow range of 10(-4) to 50 mph, representing a factor of 500,000 in differences in air velocity. Diverse applications have been outlined herein. This is the first case on record where measurement of unassisted airflow in the interstitial air of stored grain has been successfully executed, and which enabled determination of airflow speeds in the range of 0.5 to 7.5 times 10(-4) mph (=3 to 45 inches per hour).

  14. Historical collections reveal patterns of diffusion of sweet potato in Oceania obscured by modern plant movements and recombination.

    PubMed

    Roullier, Caroline; Benoit, Laure; McKey, Doyle B; Lebot, Vincent

    2013-02-01

    The history of sweet potato in the Pacific has long been an enigma. Archaeological, linguistic, and ethnobotanical data suggest that prehistoric human-mediated dispersal events contributed to the distribution in Oceania of this American domesticate. According to the "tripartite hypothesis," sweet potato was introduced into Oceania from South America in pre-Columbian times and was then later newly introduced, and diffused widely across the Pacific, by Europeans via two historically documented routes from Mexico and the Caribbean. Although sweet potato is the most convincing example of putative pre-Columbian connections between human occupants of Polynesia and South America, the search for genetic evidence of pre-Columbian dispersal of sweet potato into Oceania has been inconclusive. Our study attempts to fill this gap. Using complementary sets of markers (chloroplast and nuclear microsatellites) and both modern and herbarium samples, we test the tripartite hypothesis. Our results provide strong support for prehistoric transfer(s) of sweet potato from South America (Peru-Ecuador region) into Polynesia. Our results also document a temporal shift in the pattern of distribution of genetic variation in sweet potato in Oceania. Later reintroductions, accompanied by recombination between distinct sweet potato gene pools, have reshuffled the crop's initial genetic base, obscuring primary patterns of diffusion and, at the same time, giving rise to an impressive number of local variants. Moreover, our study shows that phenotypes, names, and neutral genes do not necessarily share completely parallel evolutionary histories. Multidisciplinary approaches, thus, appear necessary for accurate reconstruction of the intertwined histories of plants and humans.

  15. Movement Patterns and Residency of the Critically Endangered Horseshoe Crab Tachypleus tridentatus in a Semi-Enclosed Bay Determined Using Acoustic Telemetry.

    PubMed

    Wada, Toshifumi; Mitsushio, Takahiro; Inoue, Shinya; Koike, Hiroko; Kawabe, Ryo

    2016-01-01

    The horseshoe crab Tachypleus tridentatus is critically endangered in Japan due to rapidly decreasing numbers resulting from the loss of tidal flats and sandy beaches, and the deterioration of coastal environments. We monitored the year-round migratory patterns and residency of this species in a coastal embayment at Tsuyazaki, Japan, using acoustic telemetry. Total 20 adult crabs (15 males and 5 females) were tagged with ultrasonic transmitters and tracked during two periods (2006-2008; n = 10 and 2007-2009; n = 10). Adult crabs were more active during periods of higher water temperatures and their activity peaked in July, during the spawning period. Water temperature appeared to be one of the key factors influencing the movement patterns for the species. Moreover, the crabs tended to be more active at night than in the day. The nocturnal activity pattern was clearly evident before and during the reproductive period (May-August). Tracking data also showed that one pair-bond was maintained for a maximum of 17 days after the pair-bonded female had spawned. Overall, 11 males (73% of 15 individuals) remained in the bay area over winter, whereas three females (60% of 5 individuals) overwintered outside of the bay. Telemetry data showed that over 60% (13 of 20) of tagged crabs overwintered within the bay where there are sandy beaches, mudflats, and scattered seagrass beds. This year-round residence by adult T. tridentatus in the bay area identifies it as a critical habitat for the management of this species, regardless of life-stage. Not only is it a comprehensive management strategy that effectively reflects this species' habitat use patterns but also its implementation, such as the establishment of a protected area, would contribute to its conservation.

  16. Movement Patterns and Residency of the Critically Endangered Horseshoe Crab Tachypleus tridentatus in a Semi-Enclosed Bay Determined Using Acoustic Telemetry

    PubMed Central

    Wada, Toshifumi; Mitsushio, Takahiro; Inoue, Shinya; Koike, Hiroko; Kawabe, Ryo

    2016-01-01

    The horseshoe crab Tachypleus tridentatus is critically endangered in Japan due to rapidly decreasing numbers resulting from the loss of tidal flats and sandy beaches, and the deterioration of coastal environments. We monitored the year-round migratory patterns and residency of this species in a coastal embayment at Tsuyazaki, Japan, using acoustic telemetry. Total 20 adult crabs (15 males and 5 females) were tagged with ultrasonic transmitters and tracked during two periods (2006–2008; n = 10 and 2007–2009; n = 10). Adult crabs were more active during periods of higher water temperatures and their activity peaked in July, during the spawning period. Water temperature appeared to be one of the key factors influencing the movement patterns for the species. Moreover, the crabs tended to be more active at night than in the day. The nocturnal activity pattern was clearly evident before and during the reproductive period (May–August). Tracking data also showed that one pair-bond was maintained for a maximum of 17 days after the pair-bonded female had spawned. Overall, 11 males (73% of 15 individuals) remained in the bay area over winter, whereas three females (60% of 5 individuals) overwintered outside of the bay. Telemetry data showed that over 60% (13 of 20) of tagged crabs overwintered within the bay where there are sandy beaches, mudflats, and scattered seagrass beds. This year-round residence by adult T. tridentatus in the bay area identifies it as a critical habitat for the management of this species, regardless of life-stage. Not only is it a comprehensive management strategy that effectively reflects this species’ habitat use patterns but also its implementation, such as the establishment of a protected area, would contribute to its conservation. PMID:26863205

  17. Movement Patterns and Residency of the Critically Endangered Horseshoe Crab Tachypleus tridentatus in a Semi-Enclosed Bay Determined Using Acoustic Telemetry.

    PubMed

    Wada, Toshifumi; Mitsushio, Takahiro; Inoue, Shinya; Koike, Hiroko; Kawabe, Ryo

    2016-01-01

    The horseshoe crab Tachypleus tridentatus is critically endangered in Japan due to rapidly decreasing numbers resulting from the loss of tidal flats and sandy beaches, and the deterioration of coastal environments. We monitored the year-round migratory patterns and residency of this species in a coastal embayment at Tsuyazaki, Japan, using acoustic telemetry. Total 20 adult crabs (15 males and 5 females) were tagged with ultrasonic transmitters and tracked during two periods (2006-2008; n = 10 and 2007-2009; n = 10). Adult crabs were more active during periods of higher water temperatures and their activity peaked in July, during the spawning period. Water temperature appeared to be one of the key factors influencing the movement patterns for the species. Moreover, the crabs tended to be more active at night than in the day. The nocturnal activity pattern was clearly evident before and during the reproductive period (May-August). Tracking data also showed that one pair-bond was maintained for a maximum of 17 days after the pair-bonded female had spawned. Overall, 11 males (73% of 15 individuals) remained in the bay area over winter, whereas three females (60% of 5 individuals) overwintered outside of the bay. Telemetry data showed that over 60% (13 of 20) of tagged crabs overwintered within the bay where there are sandy beaches, mudflats, and scattered seagrass beds. This year-round residence by adult T. tridentatus in the bay area identifies it as a critical habitat for the management of this species, regardless of life-stage. Not only is it a comprehensive management strategy that effectively reflects this species' habitat use patterns but also its implementation, such as the establishment of a protected area, would contribute to its conservation. PMID:26863205

  18. Abnormalities of CSF flow patterns in the cerebral aqueduct in treatment-resistant late-life depression: a potential biomarker of microvascular angiopathy.

    PubMed

    Naish, Josephine H; Baldwin, Robert C; Patankar, Tufail; Jeffries, Suzanne; Burns, Alistair S; Taylor, Christopher J; Waterton, John C; Jackson, Alan

    2006-09-01

    There is growing evidence that microvascular angiopathy (MVA) plays an important role in the development of dementia and affective disorders in older people. At currently available image resolutions it is not possible to image directly the vascular changes associated with MVA, but the effects on blood and cerebrospinal fluid (CSF) flow may be detectable. The aim of this study was to investigate a potential biomarker for MVA based on MRI of abnormalities in CSF flow. Since there is considerable indirect evidence that treatment resistance in late-onset depressive disorder is related to MVA, we assessed the method in a group of 22 normal volunteers and 29 patients with responsive (N=21) or treatment-resistant (N=8) late-onset depressive disorder. Single-slice quantified phase-contrast (PC) images of cerebral blood and CSF flow were collected at 15 points over a cardiac cycle, and the resulting flow curves were parameterized. Significant differences in the CSF flow (width of systolic flow peak and diastolic flow volume, both P<0.01) through the cerebral aqueduct were observed for the group of treatment-resistant patients when compared to age matched controls. No significant difference was observed for a group of 21 patients with treatment-responsive depression. The findings support the hypothesis that MR measurement of CSF flow abnormalities provides a biomarker of MVA, and thus could have application in a wide range of age-related diseases.

  19. Movement Disorders

    MedlinePlus

    ... want them to. If you have a movement disorder, you experience these kinds of impaired movement. Dyskinesia ... and is a common symptom of many movement disorders. Tremors are a type of dyskinesia. Nerve diseases ...

  20. Habitat use and movement patterns of Northern Pintails during spring in northern Japan: the importance of agricultural lands

    USGS Publications Warehouse

    Yamaguchi, Noriyuki M.; Hupp, Jerry W.; Flint, Paul L.; Pearce, John M.; Shigeta, Yusuke; Shimada, Tetsuo; Hiraoka, Emiko N.; Higuchi, Hiroyoshi

    2012-01-01

    From 2006 to 2009, we marked 198 Northern Pintails (Anas acuta) with satellite transmitters on their wintering areas in Japan to study their migration routes and habitat use in spring staging areas. We hypothesized that the distribution of pintails during spring staging was influenced by patterns of land use and expected that the most frequently used areas would have more agricultural habitat than lesser-used areas. We obtained 3031 daily locations from 163 migrant pintails marked with satellite transmitters and identified 524 stopover sites. Based on a fixed kernel home range analysis of stopover utilization distribution (UD), core staging areas (areas within the 50% UD) were identified in northern Honshu and western Hokkaido, and were used by 71% of marked pintails. Core staging areas had a greater proportion of rice fields than peripheral (51–95% UD) and rarely used (outside the 95% UD) staging areas. Stopover sites also contained more rice fields and other agricultural land than were available at regional scales, indicating that pintails selected rice and other agricultural habitats at regional and local scales. Pintails remained at spring staging areas an average of 51 d. Prolonged staging in agricultural habitats of northern Japan was likely necessary for pintails to prepare for transoceanic migration to Arctic nesting areas in eastern Russia.

  1. Vertical Movements and Patterns in Diving Behavior of Whale Sharks as Revealed by Pop-Up Satellite Tags in the Eastern Gulf of Mexico

    PubMed Central

    Tyminski, John P.; de la Parra-Venegas, Rafael; González Cano, Jaime; Hueter, Robert E.

    2015-01-01

    The whale shark (Rhincodon typus) is a wide-ranging, filter-feeding species typically observed at or near the surface. This shark’s sub-surface habits and behaviors have only begun to be revealed in recent years through the use of archival and satellite tagging technology. We attached pop-up satellite archival transmitting tags to 35 whale sharks in the southeastern Gulf of Mexico off the Yucatan Peninsula from 2003–2012 and three tags to whale sharks in the northeastern Gulf off Florida in 2010, to examine these sharks’ long-term movement patterns and gain insight into the underlying factors influencing their vertical habitat selection. Archived data were received from 31 tags deployed on sharks of both sexes with total lengths of 5.5–9 m. Nine of these tags were physically recovered facilitating a detailed long-term view into the sharks’ vertical movements. Whale sharks feeding inshore on fish eggs off the northeast Yucatan Peninsula demonstrated reverse diel vertical migration, with extended periods of surface swimming beginning at sunrise followed by an abrupt change in the mid-afternoon to regular vertical oscillations, a pattern that continued overnight. When in oceanic waters, sharks spent about 95% of their time within epipelagic depths (<200 m) but regularly undertook very deep (“extreme”) dives (>500 m) that largely occurred during daytime or twilight hours (max. depth recorded 1,928 m), had V-shaped depth-time profiles, and comprised more rapid descents (0.68 m sec-1) than ascents (0.50 m sec-1). Nearly half of these extreme dives had descent profiles with brief but conspicuous changes in vertical direction at a mean depth of 475 m. We hypothesize these stutter steps represent foraging events within the deep scattering layer, however, the extreme dives may have additional functions. Overall, our results demonstrate complex and dynamic patterns of habitat utilization for R. typus that appear to be in response to changing biotic and abiotic

  2. Vertical Movements and Patterns in Diving Behavior of Whale Sharks as Revealed by Pop-Up Satellite Tags in the Eastern Gulf of Mexico.

    PubMed

    Tyminski, John P; de la Parra-Venegas, Rafael; González Cano, Jaime; Hueter, Robert E

    2015-01-01

    The whale shark (Rhincodon typus) is a wide-ranging, filter-feeding species typically observed at or near the surface. This shark's sub-surface habits and behaviors have only begun to be revealed in recent years through the use of archival and satellite tagging technology. We attached pop-up satellite archival transmitting tags to 35 whale sharks in the southeastern Gulf of Mexico off the Yucatan Peninsula from 2003-2012 and three tags to whale sharks in the northeastern Gulf off Florida in 2010, to examine these sharks' long-term movement patterns and gain insight into the underlying factors influencing their vertical habitat selection. Archived data were received from 31 tags deployed on sharks of both sexes with total lengths of 5.5-9 m. Nine of these tags were physically recovered facilitating a detailed long-term view into the sharks' vertical movements. Whale sharks feeding inshore on fish eggs off the northeast Yucatan Peninsula demonstrated reverse diel vertical migration, with extended periods of surface swimming beginning at sunrise followed by an abrupt change in the mid-afternoon to regular vertical oscillations, a pattern that continued overnight. When in oceanic waters, sharks spent about 95% of their time within epipelagic depths (<200 m) but regularly undertook very deep ("extreme") dives (>500 m) that largely occurred during daytime or twilight hours (max. depth recorded 1,928 m), had V-shaped depth-time profiles, and comprised more rapid descents (0.68 m sec-1) than ascents (0.50 m sec-1). Nearly half of these extreme dives had descent profiles with brief but conspicuous changes in vertical direction at a mean depth of 475 m. We hypothesize these stutter steps represent foraging events within the deep scattering layer, however, the extreme dives may have additional functions. Overall, our results demonstrate complex and dynamic patterns of habitat utilization for R. typus that appear to be in response to changing biotic and abiotic conditions

  3. Joint-Angle Coordination Patterns Ensure Stabilization of a Body-Plus-Tool System in Point-to-Point Movements with a Rod

    PubMed Central

    Valk, Tim A.; Mouton, Leonora J.; Bongers, Raoul M.

    2016-01-01

    When performing a goal-directed action with a tool, it is generally assumed that the point of control of the action system is displaced from the hand to the tool, implying that body and tool function as one system. Studies of how actions with tools are performed have been limited to studying either end-effector kinematics or joint-angle coordination patterns. Because joint-angle coordination patterns affect end-effector kinematics, the current study examined them together, with the aim of revealing how body and tool function as one system. Seated participants made point-to-point movements with their index finger, and with rods of 10, 20, and 30 cm attached to their index finger. Start point and target were presented on a table in front of them, and in half of the conditions a participant displacement compensated for rod length. Results revealed that the kinematics of the rod's tip showed higher peak velocity, longer deceleration time, and more curvature with longer rods. End-effector movements were more curved in the horizontal plane when participants were not displaced. Joint-angle trajectories were similar across rod lengths when participants were displaced, whereas more extreme joint-angles were used with longer rods when participants were not displaced. Furthermore, in every condition the end-effector was stabilized to a similar extent; both variability in joint-angle coordination patterns that affected end-effector position and variability that did not affect end-effector position increased in a similar way vis-à-vis rod length. Moreover, the increase was higher in those conditions, in which participants were not displaced. This suggests that during tool use, body and tool are united in a single system so as to stabilize the end-effector kinematics in a similar way that is independent of tool length. In addition, the properties of the actual trajectory of the end-effector, as well as the actual joint-angles used, depend on the length of the tool and the

  4. Vertical Movements and Patterns in Diving Behavior of Whale Sharks as Revealed by Pop-Up Satellite Tags in the Eastern Gulf of Mexico.

    PubMed

    Tyminski, John P; de la Parra-Venegas, Rafael; González Cano, Jaime; Hueter, Robert E

    2015-01-01

    The whale shark (Rhincodon typus) is a wide-ranging, filter-feeding species typically observed at or near the surface. This shark's sub-surface habits and behaviors have only begun to be revealed in recent years through the use of archival and satellite tagging technology. We attached pop-up satellite archival transmitting tags to 35 whale sharks in the southeastern Gulf of Mexico off the Yucatan Peninsula from 2003-2012 and three tags to whale sharks in the northeastern Gulf off Florida in 2010, to examine these sharks' long-term movement patterns and gain insight into the underlying factors influencing their vertical habitat selection. Archived data were received from 31 tags deployed on sharks of both sexes with total lengths of 5.5-9 m. Nine of these tags were physically recovered facilitating a detailed long-term view into the sharks' vertical movements. Whale sharks feeding inshore on fish eggs off the northeast Yucatan Peninsula demonstrated reverse diel vertical migration, with extended periods of surface swimming beginning at sunrise followed by an abrupt change in the mid-afternoon to regular vertical oscillations, a pattern that continued overnight. When in oceanic waters, sharks spent about 95% of their time within epipelagic depths (<200 m) but regularly undertook very deep ("extreme") dives (>500 m) that largely occurred during daytime or twilight hours (max. depth recorded 1,928 m), had V-shaped depth-time profiles, and comprised more rapid descents (0.68 m sec-1) than ascents (0.50 m sec-1). Nearly half of these extreme dives had descent profiles with brief but conspicuous changes in vertical direction at a mean depth of 475 m. We hypothesize these stutter steps represent foraging events within the deep scattering layer, however, the extreme dives may have additional functions. Overall, our results demonstrate complex and dynamic patterns of habitat utilization for R. typus that appear to be in response to changing biotic and abiotic conditions

  5. Home range, movement, and distribution patterns of the threatened dragonfly Sympetrum depressiusculum (Odonata: Libellulidae): a thousand times greater territory to protect?

    PubMed

    Dolný, Aleš; Harabiš, Filip; Mižičová, Hana

    2014-01-01

    Dragonflies are good indicators of environmental health and biodiversity. Most studies addressing dragonfly ecology have focused on the importance of aquatic habitats, while the value of surrounding terrestrial habitats has often been overlooked. However, species associated with temporary aquatic habitats must persist in terrestrial environments for long periods. Little is known about the importance of terrestrial habitat patches for dragonflies, or about other factors that initiate or influence dispersal behaviour. The aim of this study was to reveal the relationship between population dynamics of the threatened dragonfly species Sympetrum depressiusculum at its natal site and its dispersal behaviour or routine movements within its terrestrial home range. We used a mark-release-recapture method (marking 2,881 adults) and exuviae collection with the Jolly-Seber model and generalized linear models to analyse seasonal and spatial patterns of routine movement in a heterogeneous Central European landscape. Our results show that utilisation of terrestrial habitat patches by adult dragonflies is not random and may be relatively long term (approximately 3 mo). Adult dragonflies were present only in areas with dense vegetation that provided sufficient resources; the insects were absent from active agricultural patches (p = 0.019). These findings demonstrate that even a species tightly linked to its natal site utilises an area that is several orders of magnitude larger than the natal site. Therefore, negative trends in the occurrence of various dragonfly species may be associated not only with disturbances to their aquatic habitats, but also with changes in the surrounding terrestrial landscape. PMID:25006671

  6. Regional Patterns of Elevated Alpha and High-Frequency Electroencephalographic Activity during Nonrapid Eye Movement Sleep in Chronic Insomnia: A Pilot Study

    PubMed Central

    Riedner, Brady A.; Goldstein, Michael R.; Plante, David T.; Rumble, Meredith E.; Ferrarelli, Fabio; Tononi, Giulio; Benca, Ruth M.

    2016-01-01

    Study Objectives: To examine nonrapid eye movement (NREM) sleep in insomnia using high-density electroencephalography (EEG). Methods: All-night sleep recordings with 256 channel high-density EEG were analyzed for 8 insomnia subjects (5 females) and 8 sex and age-matched controls without sleep complaints. Spectral analyses were conducted using unpaired t-tests and topographical differences between groups were assessed using statistical non-parametric mapping. Five minute segments of deep NREM sleep were further analyzed using sLORETA cortical source imaging. Results: The initial topographic analysis of all-night NREM sleep EEG revealed that insomnia subjects had more high-frequency EEG activity (> 16 Hz) compared to good sleeping controls and that the difference between groups was widespread across the scalp. In addition, the analysis also showed that there was a more circumscribed difference in theta (4–8 Hz) and alpha (8–12 Hz) power bands between groups. When deep NREM sleep (N3) was examined separately, the high-frequency difference between groups diminished, whereas the higher regional alpha activity in insomnia subjects persisted. Source imaging analysis demonstrated that sensory and sensorimotor cortical areas consistently exhibited elevated levels of alpha activity during deep NREM sleep in insomnia subjects relative to good sleeping controls. Conclusions: These results suggest that even during the deepest stage of sleep, sensory and sensorimotor areas in insomnia subjects may still be relatively active compared to control subjects and to the rest of the sleeping brain. Citation: Riedner BA, Goldstein MR, Plante DT, Rumble ME, Ferrarelli F, Tononi G, Benca RM. Regional patterns of elevated alpha and high-frequency electroencephalographic activity during nonrapid eye movement sleep in chronic insomnia: a pilot study. SLEEP 2016;39(4):801–812. PMID:26943465

  7. Differential Patterns of Abnormal Activity and Connectivity in the Amygdala-Prefrontal Circuitry in Bipolar-I and Bipolar-NOS Youth

    ERIC Educational Resources Information Center

    Ladouceur, Cecile D.; Farchione, Tiffany; Diwadkar, Vaibhav; Pruitt, Patrick; Radwan, Jacqueline; Axelson, David A.; Birmaher, Boris; Phillips, Mary L.

    2011-01-01

    Objective: The functioning of neural systems supporting emotion processing and regulation in youth with bipolar disorder not otherwise specified (BP-NOS) remains poorly understood. We sought to examine patterns of activity and connectivity in youth with BP-NOS relative to youth with bipolar disorder type I (BP-I) and healthy controls (HC). Method:…

  8. Patterns of soil carbon and nitrogen in relation to soil movement under different land uses in mountain farmland fields (South Central Pyrenees)

    NASA Astrophysics Data System (ADS)

    Navas, A.; Gaspar, L.; López-Vicente, M.; Machín, J.

    2009-04-01

    Cultivation on mountain landscapes has been identified as a main factor triggering soil erosion. The loss of soil particles and its redistribution across the landscape is associated to that of soil nutrients. Patterns of soil erosion and of the transport and redistribution of soil particles appear to be closely linked to that of carbon in soils. In this work the redistribution of total organic carbon and nitrogen and that of soil particles is analysed in different geomorphic parts of mountain farmland fields. A southern orientated hillslope in the Central Spanish Pyrenees was selected as representative of main land uses. In the region, farmland abandonment during the last decades affects 74 % of its surface and therefore patterns of soil and nutrient losses in the fields are affected by land abandonments and tillage. A set of cultivated and abandoned fields with different ages of land abandonment, slope gradients and length were selected to conduct this study. In each of the fields, sampling was carried out in different parts of the slope to assess the pattern of particle size distribution and of total organic carbon (TOC) and total nitrogen (TN). Other general soil properties analysed: pH, EC and carbonate contents provided supplementary information for better understanding soil and nutrient redistribution patterns. In addition, information provided by a previous research using fallout caesium 137 was used to document soil movement in these fields. At the bottom slope of the fields significant increases in the sand percentage occurs whereas the clay contents decrease slightly. This could be due to the export of the finest fractions with high runoff in spite that fields are surrounded with stone walls as well as to some clay leaching in the soil profile, as suggested by the lowest values of EC at the bottom of the slope. The results indicate that in general TOC increases from the crest to the bottom slope of the fields. Percentages of TOC increases range from 5 to

  9. Ecological Impacts of the Cerro Grande Fire: Predicting Elk Movement and Distribution Patterns in Response to Vegetative Recovery through Simulation Modeling October 2005

    SciTech Connect

    Rupp, Susan P.

    2005-10-01

    In May 2000, the Cerro Grande Fire burned approximately 17,200 ha in north-central New Mexico as the result of an escaped prescribed burn initiated by Bandelier National Monument. The interaction of large-scale fires, vegetation, and elk is an important management issue, but few studies have addressed the ecological implications of vegetative succession and landscape heterogeneity on ungulate populations following large-scale disturbance events. Primary objectives of this research were to identify elk movement pathways on local and landscape scales, to determine environmental factors that influence elk movement, and to evaluate movement and distribution patterns in relation to spatial and temporal aspects of the Cerro Grande Fire. Data collection and assimilation reflect the collaborative efforts of National Park Service, U.S. Forest Service, and Department of Energy (Los Alamos National Laboratory) personnel. Geographic positioning system (GPS) collars were used to track 54 elk over a period of 3+ years and locational data were incorporated into a multi-layered geographic information system (GIS) for analysis. Preliminary tests of GPS collar accuracy indicated a strong effect of 2D fixes on position acquisition rates (PARs) depending on time of day and season of year. Slope, aspect, elevation, and land cover type affected dilution of precision (DOP) values for both 2D and 3D fixes, although significant relationships varied from positive to negative making it difficult to delineate the mechanism behind significant responses. Two-dimensional fixes accounted for 34% of all successfully acquired locations and may affect results in which those data were used. Overall position acquisition rate was 93.3% and mean DOP values were consistently in the range of 4.0 to 6.0 leading to the conclusion collar accuracy was acceptable for modeling purposes. SAVANNA, a spatially explicit, process-oriented ecosystem model, was used to simulate successional dynamics. Inputs to the

  10. Repeated stress-induced expression pattern alterations of the hippocampal chloride transporters KCC2 and NKCC1 associated with behavioral abnormalities in female mice.

    PubMed

    Tsukahara, Takao; Masuhara, Masaaki; Iwai, Haruki; Sonomura, Takahiro; Sato, Tomoaki

    2015-09-11

    The balance of cation-chloride co-transporters, particularly KCC2 and NKCC1, is critical for GABAergic inhibitory signaling. However, KCC2/NKCC1 balance is disrupted in many neurodegenerative diseases. Moreover, correlations between chronic stress, KCC2 and NKCC1 in the hippocampus remain poorly understood. Despite the fact that emotional disorders in humans are far more prevalent in women, there have been relatively few studies about female subjects. Here we investigated behaviors and expression patterns of KCC2 and NKCC1 in the hippocampi of female mice under chronic stress. Repeated stress (RS) was induced in experimental mice by repeated forced water administration. Then, expression patterns of GABAergic signaling molecules were identified by immunohistochemical analysis and performance was assessed using several behavioral tests. The results of semi-quantitative analysis showed that RS decreased KCC2 expression and increased NKCC1 expression in membranes of granular and pyramidal cells in the hippocampus. The novel object recognition (NOR) test and sociability test revealed that RS induced cognitive and sociability deficits, whereas RS increased the time spent in the open arms of the elevated plus maze test and induced attention deficits in other tests. In summary, RS induced alterations in membrane KCC2/NKCC1 balance in the hippocampus of female mice, which may contribute to GABAergic disinhibition associated with cognitional, sociability and attention deficits. PMID:26239662

  11. Sensory aspects of movement disorders

    PubMed Central

    Patel, Neepa; Jankovic, Joseph; Hallett, Mark

    2016-01-01

    Movement disorders, which include disorders such as Parkinson’s disease, dystonia, Tourette’s syndrome, restless legs syndrome, and akathisia, have traditionally been considered to be disorders of impaired motor control resulting predominantly from dysfunction of the basal ganglia. This notion has been revised largely because of increasing recognition of associated behavioural, psychiatric, autonomic, and other non-motor symptoms. The sensory aspects of movement disorders include intrinsic sensory abnormalities and the effects of external sensory input on the underlying motor abnormality. The basal ganglia, cerebellum, thalamus, and their connections, coupled with altered sensory input, seem to play a key part in abnormal sensorimotor integration. However, more investigation into the phenomenology and physiological basis of sensory abnormalities, and about the role of the basal ganglia, cerebellum, and related structures in somatosensory processing, and its effect on motor control, is needed. PMID:24331796

  12. Up-regulation of the mammalian target of rapamycin complex 1 subunit Raptor by aldosterone induces abnormal pulmonary artery smooth muscle cell survival patterns to promote pulmonary arterial hypertension.

    PubMed

    Aghamohammadzadeh, Reza; Zhang, Ying-Yi; Stephens, Thomas E; Arons, Elena; Zaman, Paula; Polach, Kevin J; Matar, Majed; Yung, Lai-Ming; Yu, Paul B; Bowman, Frederick P; Opotowsky, Alexander R; Waxman, Aaron B; Loscalzo, Joseph; Leopold, Jane A; Maron, Bradley A

    2016-07-01

    Activation of the mammalian target of rapamycin complex 1 (mTORC1) subunit Raptor induces cell growth and is a downstream target of Akt. Elevated levels of aldosterone activate Akt, and, in pulmonary arterial hypertension (PAH), correlate with pulmonary arteriole thickening, which suggests that mTORC1 regulation by aldosterone may mediate adverse pulmonary vascular remodeling. We hypothesized that aldosterone-Raptor signaling induces abnormal pulmonary artery smooth muscle cell (PASMC) survival patterns to promote PAH. Remodeled pulmonary arterioles from SU-5416/hypoxia-PAH rats and monocrotaline-PAH rats with hyperaldosteronism expressed increased levels of the Raptor target, p70S6K, which provided a basis for investigating aldosterone-Raptor signaling in human PASMCs. Aldosterone (10(-9) to 10(-7) M) increased Akt/mTOR/Raptor to activate p70S6K and increase proliferation, viability, and apoptosis resistance in PASMCs. In PASMCs transfected with Raptor-small interfering RNA or treated with spironolactone/eplerenone, aldosterone or pulmonary arterial plasma from patients with PAH failed to increase p70S6K activation or to induce cell survival in vitro Optimal inhibition of pulmonary arteriole Raptor was achieved by treatment with Staramine-monomethoxy polyethylene glycol that was formulated with Raptor-small interfering RNA plus spironolactone in vivo, which decreased arteriole muscularization and pulmonary hypertension in 2 experimental animal models of PAH in vivo Up-regulation of mTORC1 by aldosterone is a cri