Brain structural network topological alterations of the left prefrontal and limbic cortex in psychogenic erectile dysfunction.

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Chen, Jianhuai; Chen, Yun; Gao, Qingqiang; Chen, Guotao; Dai, Yutian; Yao, Zhijian; Lu, Qing

2018-05-01

Despite increasing understanding of the cerebral functional changes and structural abnormalities in erectile dysfunction, alterations in the topological organization of brain networks underlying psychogenic erectile dysfunction remain unclear. Here, based on the diffusion tensor image data of 25 patients and 26 healthy controls, we investigated the topological organization of brain structural networks and its correlations with the clinical variables using the graph theoretical analysis. Patients displayed a preserved overall small-world organization and exhibited a less connectivity strength in the left inferior frontal gyrus, amygdale and the right inferior temporal gyrus. Moreover, an abnormal hub pattern was observed in patients, which might disturb the information interactions of the remaining brain network. Additionally, the clustering coefficient of the left hippocampus was positively correlated with the duration of patients and the normalized betweenness centrality of the right anterior cingulate gyrus and the left calcarine fissure were negatively correlated with the sum scores of the 17-item Hamilton Depression Rating Scale. These findings suggested that the damaged white matter and the abnormal hub distribution of the left prefrontal and limbic cortex might contribute to the pathogenesis of psychogenic erectile dysfunction and provided new insights into the understanding of the pathophysiological mechanisms of psychogenic erectile dysfunction.

Corticosterone release in oxytocin gene deletion mice following exposure to psychogenic versus non-psychogenic stress.

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Amico, Janet A; Cai, Hou-ming; Vollmer, Regis R

2008-09-19

Both anxiety-related behavior [J.A. Amico, R.C. Mantella, R.R. Vollmer, X. Li, Anxiety and stress responses in female oxytocin deficient mice, J. Neuroendocrinol. 16 (2004) 1-6; R.C. Mantella, R.R. Vollmer, X. Li, J.A. Amico, Female oxytocin-deficient mice display enhanced anxiety-related behavior, Endocrinology 144 (2003) 2291-2296] and the release of corticosterone following a psychogenic stress such as exposure to platform shaker was greater in female [J.A. Amico, R.C. Mantella, R.R. Vollmer, X. Li, Anxiety and stress responses in female oxytocin deficient mice, J. Neuroendocrinol. 16 (2004) 1-6; R.C. Mantella, R.R. Vollmer, L. Rinaman, X. Li, J.A. Amico, Enhanced corticosterone concentrations and attenuated Fos expression in the medial amygdala of female oxytocin knockout mice exposed to psychogenic stress, Am. J. Physiol. Regul. Integr. Comp. Physiol. 287 (2004) R1494-R1504], but not male [R.C. Mantella, R.R. Vollmer, J.A. Amico, Corticosterone release is heightened in food or water deprived oxytocin deficient male mice, Brain Res. 1058 (2005) 56-61], oxytocin gene deletion (OTKO) mice compared to wild type (WT) cohorts. In the present study we exposed OTKO and WT female mice to another psychogenic stress, inserting a rectal probe to record body temperature followed by brief confinement in a metabolic cage, and measured plasma corticosterone following the stress. OTKO mice released more corticosterone than WT mice (Pstress. In contrast, if OTKO and WT female and male mice were administered insulin-induced hypoglycemia, an acute physical stress, corticosterone release was not different between genotypes. The absence of central OT signaling pathways in female mice heightens the neuroendocrine (e.g., corticosterone) response to psychogenic stress, but not to the physical stress of insulin-induced hypoglycemia.

[Different lay etiologic attributions of psychogenically ill probrands from an epidemiologic field study].

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Thebaldi, B; Franz, M; Schellberg, D; Schepank, H

1996-01-01

The correlation between causal attributions of symptoms and sociodemographic, psychometric and clinical variables among psychogenic impaired persons is investigated in this paper. 114 individuals, who had presented psychogenic symptoms in the last year, were selected from the representative sample of the Mannheim Cohort Study. Two extreme groups have been identified through one Scale of Disease Conception: one with a somatogenic (n = 80) and the other with a psychogenic conception (n = 34). Female, younger and well educated individuals predominate in the group with psychogenic conception. In FPI the group with psychogenic conception is characterized by high depressivity, emotional lability, aggressivity, inhibition, irritability, anxiety and frankness. The diagnosis psychoneurose (ICD) is also more frequent in this group. The psychic impairment is more severe in the group with psychogenic conception (Impairment Score). Subjects of the group with psychogenic conception utilized psychotherapeutic services more frequently. In the logistical regression the variables agecohort, the FPIdimensions "Sociability" and "Inhibition", the number of psychic and physical symptoms in the last year and the BSS-subscale "psychic impairment" prove to be relevant in the estimate of relative risk for the type of causal explanation for symptoms.

Coping Strategies and IQ in Psychogenic Movement Disorders and Paralysis

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van Beilen, M.; Griffioen, Brecht T.; Leenders, Klaus L.

2009-01-01

Inadequate coping strategies may cause some patients to develop psychogenic symptoms in periods of stress. This may be more prominent in patients with lower intelligence levels. Twenty-six patients with psychogenic neurological disorders (PND) were tested for coping abilities and intelligence and

[Functional (psychogenic) vertigo].

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Diukova, G M; Zamergrad, M V; Golubev, V L; Adilova, S M; Makarov, S A

Psychogenic (functional) vertigo is in second place by frequency after benign positional paroxysmal vertigo. It is often difficult to make the diagnosis, diagnostic program is expensive and traditional treatment often is not effective. This literature review covers current concepts on the terminology, clinical signs, pathogenesis and treatment approaches with regard to functional vertigo. Special attention is given to cerebral mechanisms of the pathogenesis including cognitive aspects.

[Epidemiologic findings on the spontaneous long-term course of psychogenic disease over 10 years].

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Franz, M; Schepank, H; Reister, G; Schellberg, D

1994-01-01

207 individuals were selected from a random sample of the adult urban population of Mannheim according to the criterion of medium psychogenic impairment (high-risk population) and investigated three times between 1979 and 1991 with regard to prevalence and severity of psychogenic disorders. In contrast to clinical investigations, the present data render statements on the spontaneous course of psychogenic disorders in the general population. The existing psychogenic impairment was determined by means of various operationalizations (symptomatology, ICD-diagnoses, severity of impairment). The available data indicate a high stability of psychogenic impairment in the spontaneous course. Group statistically the severity of impairment even increases in the long term course. However, different subtypes of course in the investigated high-risk population can be identified by a cluster analysis.

Sight and blindness in the same person: Gating in the visual system.

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Strasburger, Hans; Waldvogel, Bruno

2015-12-01

We present the case of a patient having dissociative identity disorder (DID) who-after 15 years of misdiagnosed cortical blindness--step-by-step regained sight during psychotherapeutic treatment. At first only a few personality states regained vision whereas others remained blind. This could be confirmed by electrophysiological measurement, in which visual evoked potentials (VEPs) were absent in the blind personality states but were normal and stable in the seeing states. A switch between these states could happen within seconds. We assume a top-down modulation of activity in the primary visual pathway as a neural basis of such psychogenic blindness, possibly at the level of the thalamus. VEPs therefore do not allow separating psychogenic blindness from organic disruption of the visual pathway. In summary, psychogenic blindness seems to suppress visual information at an early neural stage. © 2015 The Institute of Psychology, Chinese Academy of Sciences and Wiley Publishing Asia Pty Ltd.

Psychogenic Urinary Retention in Children: A Case Report

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Kong-Sang Wan

2010-10-01

Full Text Available Psychogenic urinary retention occurs relatively infrequently in children and is less common than in adults. The influence of psychogenic factors on voiding generally results in an irritative syndrome, but rarely in urinary retention. A definitive diagnosis is established by excluding other pathological conditions. Evaluation includes urine culture, renal echography, spine magnetic resonance imaging, voiding cysto-urethrography, intravenous pyelography, and uroflowmetry. Here, we report on a 6-year-old girl with a 1-month history of voiding difficulty. Urology studies, including urine culture, revealed Escherichia coli, which was not present in preadmission urine cultures. Renal ultrasound and radiological images showed no gross abnormalities or vesicoureteral reflux, but uroflowmetry showed a low flow rate with residual urine. The results of imaging studies and pediatric psychiatric consultation led to a diagnosis of psychogenic urinary retention combined with urinary tract infection. Urinary rehabilitation included intermittent catheterization, bladder training, and supportive psychotherapy, after which the patient recovered and was discharged.

Psychogenic Low-Back Pain and Hysterical Paralysis in Adolescence.

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Kanchiku, Tsukasa; Suzuki, Hidenori; Imajo, Yasuaki; Yoshida, Yuichiro; Nishida, Norihiro; Taguchi, Toshihiko

2017-10-01

A retrospective review. The purpose of this study was to investigate the clinical outcomes in adolescents diagnosed with psychogenic low-back pain and hysterical paralysis and to evaluate the efficacy of differential diagnosis methods. The incidence of low-back pain in adolescence is similar to that in adults, but the causes of low-back pain are difficult to determine in most cases. For these patients, a definitive diagnosis of psychogenic low-back pain and hysterical paralysis as well as adequate treatment are clinically important to avoid unnecessary surgical treatment. Eleven patients (3 males and 8 females; mean age, 16.5 years; range, 13-19 y) diagnosed with psychogenic low-back pain and hysterical paralysis were followed up for 2-10.25 years (mean, 4.67 y). Nonorganic signs were observed in almost all patients. For the purpose of excluding organic disorders, the thiopentone pain study was used in patients who complained mainly of pain, and motor evoked potentials using transcranial magnetic stimulation were measured in patients experiencing primarily muscle weakness. The psychiatric diagnosis was neurosis in 9 patients, whereas it was psychosomatic disorder in 2 patients. Conservative treatment, such as physiotherapy, was performed, and at the final follow-up evaluation, outcomes were regarded as excellent in 7 patients and good in 4 patients. The prognosis of psychogenic low-back pain and hysterical paralysis in adolescence is relatively good. However, it is important to understand the characteristics of psychogenic low-back pain and hysterical paralysis in childhood and young adulthood and to perform accurate diagnosis by screening for nonorganic signs and excluding organic disorders by using the thiopentone pain study and motor evoked potentials obtained using transcranial magnetic stimulation.

Misclassification of Patients with Spinocerebellar Ataxia as having Psychogenic Postural Instability based on Computerized Dynamic Posturography

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Susan J Herdman

2011-04-01

Full Text Available Specific criteria have been developed based on computerized dynamic posturography (CDP to assist clinicians in identifying patients with psychogenic balance problems1-4. Patients with known Spinocerebellar Ataxia (SCA meet several of the criteria for psychogenic balance problem and risk being misclassified as having imbalance of psychogenic origin. However, our research shows that patients with SCA may be distinguished from patients with psychogenic balance problems in several ways. We compared test performance on CDP and the observation of specific behaviors that are associated with psychogenic balance problems in patients with SCA (n = 43 and patients with known psychogenic balance problems (n = 40. Chi square analysis was used to determine if there were significant differences between the groups for the frequency of each criterion for psychogenic CDP and Observed Behaviors. Level of significance was Bonferroni corrected for multiple comparisons. Sensitivity, specificity, and positive likelihood ratios were calculated for each criterion. Hierarchical cluster analysis was used to examine whether the two patient groups demonstrated similar groupings of criteria. Comparison of the results of these analyses identified two criteria that were significantly more frequent in the Psychogenic group than in the SCA group: Regular Periodicity of sway and Circular Sway. Sensitivity, specificity and positive likelihood ratios identified two additional criteria, Inconsistent Motor Responses and Large lateral Sway that also seem to suggest a psychogenic component to a person’s imbalance. Prospective studies are needed to validate the usefulness of these findings.

Psychogenic Equinovarus Caused by Dislocation of the Chopart Joint Complex

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Ichiro Tonogai

2018-01-01

Full Text Available Patients with conversion disorder (CD present with weakness or unexplained movement disorder that may evolve from inciting psychological events, but presentation with rigid deformity is rare. Only one case of CD presenting as foot deformity with atraumatic rigid psychogenic equinovarus has been reported previously. Here we describe a rare case of psychogenic equinovarus in a physically healthy 10-year-old boy. He had noticed left equinovarus deformity upon waking abruptly but had no history of preceding trauma and no relevant medical history. Computed tomography (CT images revealed dislocation of the left Chopart joint complex, but clinical examination did not suggest an organic neurologic disorder. On further history taking, he reported that he was under psychological stress because of being required to play baseball against his will. When he was given permission to withdraw from this stressful situation, the equinovarus improved without the need for surgical invention. This report highlights the importance of early and accurate diagnosis of psychogenic equinovarus, so that unnecessary surgery can be avoided. This is the first report of psychogenic equinovarus caused by dislocation of the Chopart joint complex that was confirmed with CT.

Validating visual disturbance types and classes used for forest soil monitoring protocols

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D. S. Page-Dumroese; A. M. Abbott; M. P. Curran; M. F. Jurgensen

2012-01-01

We describe several methods for validating visual soil disturbance classes used during forest soil monitoring after specific management operations. Site-specific vegetative, soil, and hydrologic responses to soil disturbance are needed to identify sensitive and resilient soil properties and processes; therefore, validation of ecosystem responses can provide information...

Psychogenic dysphonia: diversity of clinical and vocal manifestations in a case series

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Regina Helena Garcia Martins

2014-12-01

Full Text Available Introduction: Psychogenic dysphonia is a functional disorder with variable clinical manifestations. Objective: To assess the clinical and vocal characteristics of patients with psychogenic dysphonia in a case series. Methods: The study included 28 adult patients with psychogenic dysphonia, evaluated at a University hospital in the last ten years. Assessed variables included gender, age, occupation, vocal symptoms, vocal characteristics, and videolaryngostroboscopic findings. Results: 28 patients (26 women and 2 men were assessed. Their occupations included: housekeeper (n = 17, teacher (n = 4, salesclerk (n = 4, nurse (n = 1, retired (n = 1, and psychologist (n = 1. Sudden symptom onset was reported by 16 patients and progressive symptom onset was reported by 12; intermittent evolution was reported by 15; symptom duration longer than three months was reported by 21 patients. Videolaryngostroboscopy showed only functional disorders; no patient had structural lesions or changes in vocal fold mobility. Conversion aphonia, skeletal muscle tension, and intermittent voicing were the most frequent vocal emission manifestation forms. Conclusions: In this case series of patients with psychogenic dysphonia, the most frequent form of clinical presentation was conversion aphonia, followed by musculoskeletal tension and intermittent voicing. The clinical and vocal aspects of 28 patients with psychogenic dysphonia, as well as the particularities of each case, are discussed.

[The influence of cognitive-behavioral therapy on the P300 potential in children with psychogenic nonepileptic seizures and tension headache].

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Stolarska-Weryńska, Urszula; Steczkowska, Małgorzata; Kaciński, Marek

2016-01-01

Explaining associations between neurophysiological and neuropsychological parameteres in children and improving the measurement methods would lead to a better understanding of the pathogenesis and course of psychosomatic disease. Goal: clinical assessment of the efficacy of cognitive-behavioral therapy in the treatment of psychogenic no- nepileptic seizures and tension type headaches in children. Determining the influence of cognitive behavioral therapy on the cognitive P300 potential and whether P300 parameters in children correlate with neuropsychological parameters. 20 children with nonepileptic psychogenic seizures and 30 children with tension type headaches, aged 11.3 - 17.11 years. The final diagnosis was made in the Paediatric Neurology Clinic. The P300 examination was performed before/after therapy, with/without hyperventilation. A fixed structure therapy was implemented (10 sessions, 90 minutes each), during two weeks of hospitalization or in an outpatient clinic (9 children with tension type headache). The psychological assessment comprised of temperament questionnaires, auditory and visual memory trials, executive function and attention trials, and in some cases also intelligence testing. More significant correlations were found in children with psychogenic seizures: attention parameters correlated negatively with reaction time, and this correlation tended to fade in the second examination, after psychotherapy. In children with tension type headache a statistically insignificant tendency was found of a positive correlation between those parameters. Medium P300 parameteres in this group were better. In 17/20 of children with psychogenic seizures a clinical improvement was observed, in 3 children the symptoms persisted in a 6 month follow up, but of a lower frequency. In 11/27 of chil- dren with tension headache the symptoms persisted, also with a lower frequency. cognitive-behavioral therapy is effective in the reduction of symptoms in many cases of

Functional MR imaging of psychogenic amnesia: a case report

International Nuclear Information System (INIS)

Yang, Jong Chul; Jeong, Gwang Woo; Lee, Moo Suk; Kang, Heoung Keun; Eun, Sung Jong; Lee, Yo Han; Kim, Yong Ku

2005-01-01

We present here a case in which functional MR imaging (fMRI) was done for a patient who developed retrograde psychogenic amnesia for a four year period of her life history after a severe stressful event. We performed the fMRI study for a face recognition task using stimulation with three kinds of face photographs: recognizable familiar faces, unrecognizable friends' faces due to the psychogenic amnesia, and unfamiliar control faces. Different activation patterns between the recognizable faces and unrecognizable faces were found in the limbic area, and especially in the amygdala and hippocampus

Functional MR imaging of psychogenic amnesia: a case report

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Yang, Jong Chul; Jeong, Gwang Woo; Lee, Moo Suk; Kang, Heoung Keun; Eun, Sung Jong; Lee, Yo Han [Chonnam National Univeristy Hospital, Chonnam National University Medical School, Kwangju (Korea, Republic of); Kim, Yong Ku [Korea University Ansan Hospital, Ansan (Korea, Republic of)

2005-09-15

We present here a case in which functional MR imaging (fMRI) was done for a patient who developed retrograde psychogenic amnesia for a four year period of her life history after a severe stressful event. We performed the fMRI study for a face recognition task using stimulation with three kinds of face photographs: recognizable familiar faces, unrecognizable friends' faces due to the psychogenic amnesia, and unfamiliar control faces. Different activation patterns between the recognizable faces and unrecognizable faces were found in the limbic area, and especially in the amygdala and hippocampus.

Conversion disorder and mass psychogenic illness in child neurology.

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Mink, Jonathan W

2013-11-01

A common problem faced by neurologists is the existence of disorders that present with neurological symptoms but do not have identifiable neurological bases. Conversion disorder is the most common of these disorders. In some situations, members of a cohesive social group will develop the same or similar symptoms. This review discusses conversion disorder in children, with an emphasis on function movement disorders. It also reviews a recent occurrence of mass psychogenic illness in New York State with discussion of the key features of mass psychogenic illness. © 2013 New York Academy of Sciences.

Psychogenic dysphonia: diversity of clinical and vocal manifestations in a case series.

Science.gov (United States)

Martins, Regina Helena Garcia; Tavares, Elaine Lara Mendes; Ranalli, Paula Ferreira; Branco, Anete; Pessin, Adriana Bueno Benito

2014-01-01

Psychogenic dysphonia is a functional disorder with variable clinical manifestations. To assess the clinical and vocal characteristics of patients with psychogenic dysphonia in a case series. The study included 28 adult patients with psychogenic dysphonia, evaluated at a University hospital in the last ten years. Assessed variables included gender, age, occupation, vocal symptoms, vocal characteristics, and videolaryngostroboscopic findings. 28 patients (26 women and 2 men) were assessed. Their occupations included: housekeeper (n=17), teacher (n=4), salesclerk (n=4), nurse (n=1), retired (n=1), and psychologist (n=1). Sudden symptom onset was reported by 16 patients and progressive symptom onset was reported by 12; intermittent evolution was reported by 15; symptom duration longer than three months was reported by 21 patients. Videolaryngostroboscopy showed only functional disorders; no patient had structural lesions or changes in vocal fold mobility. Conversion aphonia, skeletal muscle tension, and intermittent voicing were the most frequent vocal emission manifestation forms. In this case series of patients with psychogenic dysphonia, the most frequent form of clinical presentation was conversion aphonia, followed by musculoskeletal tension and intermittent voicing. The clinical and vocal aspects of 28 patients with psychogenic dysphonia, as well as the particularities of each case, are discussed. Copyright © 2014 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

Review: Psychogenic Aspect of Pain & Coceptualization of Psychogenic Pain in Children

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Ali Reza Jazayeri

2004-06-01

Full Text Available Pain is the sensory and emotional experience of discomfort whiehis usually associated with actual or threatened physical damsge or irritation . Virtvally all people experience pain at all ages. Children also experience pain from the moment of birth through childhood years. Underestaning pain in children is very important , because of treatment implication and its influence in child physical and psychological development . Experienced researchers have found that pain is a concequence of emotional disorder which is observed in some patients . in many cases we have seen that a patient says to his / her clinician that she has no pain because there is no evidence of somatic disease. Dicomfont involved in psychogenic pain seems to resort primerly from psychological process. Many of physicion are familiar with unpleasant and avoidant concequences of these distortions . In these cases , it s better for us to agree with patients , experience of pain and not to prob somatic risk factors and their mechanism all the time. The researches hove recognized that psychological factors cam cause pain which is named psychogenic pain. It means that the cause of pain has psychological roots , versus organic pain which is related to discomfort is caused by tissue damage . In this study , theorical , psychological , psychoanalytical and psycho social approaches and personality characteristics description related to pain and the relations among these approaches in this area have been studied . Also, the perception of pain among children with different gender have been probed

Clinico-psychological analysis of systematic (vestibular and nonsystematic (psychogenic vertigo, therapy optimization

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Elena Mikhailovna Illarionova

2011-01-01

Full Text Available Objective: to study the clinical and psychoemotional characteristics in patients with systematic and nonsystematic vertigo and to optimize therapy. Patients and methods. The clinical features were analyzed in 25 patients with systematic vertigo and 25 patients with psychogenic vertigo. Their psychoemotional sphere was studied using the Beck depression inventory, the Spielberger-hanin personality- and situation-related anxiety inventory, and the vestibular inventory. Results. There were statistically significant clinical differences and a higher degree of anxiety-depressive disorders in the patients with psychogenic vertigo. Drug therapy in combination with stabilometric platform exercises based on the biological feedback principle was stated to be effective in patients with different types of vertigo, in those with psychogenic dizziness in particular.

Effect of lunar phase on frequency of psychogenic nonepileptic events in the EMU.

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Bolen, Robert D; Campbell, Zeke; Dennis, William A; Koontz, Elizabeth H; Pritchard, Paul B

2016-06-01

Studies of the effect of a full moon on seizures have yielded mixed results, despite a continuing prevailing belief regarding the association of lunar phase with human behavior. The potential effect of a full moon on psychogenic nonepileptic events has not been as well studied, despite what anecdotal accounts from most epilepsy monitoring unit (EMU) staff would suggest. We obtained the dates and times of all events from patients diagnosed with psychogenic nonepileptic events discharged from our EMU over a two-year period. The events were then plotted on a 29.5-day lunar calendar. Events were also broken down into lunar quarters for statistical analysis. We found a statistically significant increase in psychogenic nonepileptic events during the new moon quarter in our EMU during our studied timeframe. Our results are not concordant with the results of a similarly designed past study, raising the possibility that psychogenic nonepileptic events are not influenced by lunar phase. Copyright © 2016 Elsevier Inc. All rights reserved.

Characterizing head motion in three planes during combined visual and base of support disturbances in healthy and visually sensitive subjects.

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Keshner, E A; Dhaher, Y

2008-07-01

Multiplanar environmental motion could generate head instability, particularly if the visual surround moves in planes orthogonal to a physical disturbance. We combined sagittal plane surface translations with visual field disturbances in 12 healthy (29-31 years) and 3 visually sensitive (27-57 years) adults. Center of pressure (COP), peak head angles, and RMS values of head motion were calculated and a three-dimensional model of joint motion was developed to examine gross head motion in three planes. We found that subjects standing quietly in front of a visual scene translating in the sagittal plane produced significantly greater (pplane of platform motion significantly increased (phistory of vestibular disorder produced large, delayed compensatory head motion. Orthogonal head motions were significantly greater in visually sensitive than in healthy subjects in the dark (pplanes orthogonal to the direction of a physical perturbation. These results suggest that the mechanisms controlling head orientation in space are distinct from those that control trunk orientation in space. These behaviors would have been missed if only COP data were considered. Data suggest that rehabilitation training can be enhanced by combining visual and mechanical perturbation paradigms.

Modification of Anxious Behavior after Psychogenic Trauma and Treatment with Galanin Receptor Antagonist.

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Lyudyno, V I; Tsikunov, S G; Abdurasulova, I N; Kusov, A G; Klimenko, V M

2015-07-01

Effects of blockage of central galanin receptors on anxiety manifestations were studied in rats with psychogenic trauma. Psychogenic trauma was modeled by exposure of a group of rats to the situation when the partner was killed by a predator. Antagonist of galanin receptors was intranasally administered before stress exposure. Animal behavior was evaluated using the elevated-plus maze test, free exploratory paradigm, and open-field test. Psychogenic trauma was followed by an increase in anxiety level and appearance of agitated behavior. Blockage of galanin receptors aggravated behavioral impairment, which manifested in the pathological anxious reactions - manifestations of hypervigilance and hyperawareness. The results suggest that endogenous pool of galanin is involved into prevention of excessive CNS response to stressful stimuli typical of posttraumatic stress disorder.

Psychogenic fever in a patient with small cell lung cancer: a case report

International Nuclear Information System (INIS)

Xu, Mengdan; Zhang, Xiaoye; Xu, Zhaoguo; Cui, Guoyuan; Yu, Li; Qi, Xiaoying; Lin, Jia; Liu, Yan

2015-01-01

Fever is common in malignant tumors. We report an exceptional case of psychogenic fever in a patient with small cell lung cancer. This is the first case report of psychogenic fever in a patient with small cell lung cancer. A 61-year-old Chinese man diagnosed with small cell carcinoma on June 30, 2012, came to our department with a complaint of fever lasting more than 1 month. He had undergone chemoradiotherapy for lung cancer 6 months previously. After admission, his body temperature fluctuated in the range of 37 °C to 39 °C. Somatic symptoms associated with anxiety were obvious. A 24-item Hamilton Anxiety Scale was used to assess the patient’s condition. A score of 32 confirmed a diagnosis of severe anxiety. After a week of antianxiety treatment, the patient’s temperature returned to normal. Psychogenic fever is common in cancer patients and deserves more attention. Patients with psychogenic fever must be distinguished from patients with infectious fever (including neutropenic fever), and tumor fever. Additionally, antianxiety or antidepression treatment should be provided. A concern is that continual anxiety may adversely affect anticancer therapy

[Psychogenic purpura with hematuria and sexual pain disorder: a case report].

Science.gov (United States)

Ozyildirim, Ilker; Yücel, Başak; Aktan, Melih

2010-01-01

Psychogenic purpura (Gardner-Diamond syndrome) is the occurrence and spontaneous recurrence of painful ecchymosis following emotional stress and minor trauma. Although the exact mechanism of this syndrome remains unknown, apart from skin lesions, different types of hemorrhaging have been reported, such as epistaxis, gastrointestinal bleeding, and bleeding from the ear canals and eyes. We report a psychogenic purpura case that presented with hematuria in addition to skin lesions. Based on the psychiatric evaluation she was diagnosed with major depressive disorder, generalized anxiety disorder, and obsessive-compulsive disorder. Additionally, sexual pain disorder accompanied these disorders. With the help of antidepressant and supportive psychotherapy, the patient's ecchymosis and bleeding disappeared. During 8 months of follow-up the symptoms did not return. Vaginismus has not been reported in patients with psychogenic purpura. The presence of vaginismus, which is seen more frequently in eastern cultures and is thought to be related to sociocultural determinants, suggests that some cultural factors may be common to both psychogenic purpura and vaginismus. The aim of this case report was to call attention to a syndrome that is rarely seen and diagnosed, and to discuss its relationship to psychosocial factors. This syndrome should be considered in the differential diagnosis of not only ecchymotic lesions, but also various types of bleeding, including hematuria. Despite the fact that its etiology and treatment are not clearly understood, it should be noted that psychological factors play a role in this disease and therefore, psychopharmacological and psychotherapeutic approaches can be effective.

Shell Shock: Psychogenic Gait and Other Movement Disorders - A Film Review

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Mariana Moscovich

2013-04-01

Full Text Available Background: The psychological pressure on soldiers during World War I (WWI and other military conflicts has resulted in many reported cases of psychogenic gait as well as other movement disorders. In this paper, psychogenic movement disorders captured in the WWI film footage "War Neuroses" is reanalyzed. Methods: Two movement disorders specialists re-examined film images of 21 WWI patients with various and presumed psychogenic manifestations, pre- and post treatment. The film was recorded by Arthur Hurst, a general physician with an interest in neurology. Results: All 21 subjects were males, and all presented with symptoms relating to war trauma or a psychological stressor (e.g., being buried, shrapnel wounds, concussion, or trench fever. The most common presenting feature was a gait disorder, either pure or mixed with another movement disorder (15, followed by retrograde amnesia (2, abnormal postures (pure dystonia (1, facial spasm (1, head tremor (1, "hyperthyroidism-hyperadrenalism" (1. Nineteen patients received treatment, and the treatment was identified in nine cases. In most cases, treatment was short and patients improved almost immediately. Occupational therapy was the most common treatment. Other effective methods were hypnosis (1, relaxation (1, passive movements (2, and probable "persuasion and re-education" (6. Discussion: The high success rate in treating psychogenic disorders in Hurst's film would be considered impressive by modern standards, and has raised doubt in recent years as to whether parts of the film were staged and/or acted.

Psychogenic fever: how psychological stress affects body temperature in the clinical population.

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Oka, Takakazu

2015-01-01

Psychogenic fever is a stress-related, psychosomatic disease especially seen in young women. Some patients develop extremely high core body temperature (Tc) (up to 41°C) when they are exposed to emotional events, whereas others show persistent low-grade high Tc (37-38°C) during situations of chronic stress. The mechanism for psychogenic fever is not yet fully understood. However, clinical case reports demonstrate that psychogenic fever is not attenuated by antipyretic drugs, but by psychotropic drugs that display anxiolytic and sedative properties, or by resolving patients' difficulties via natural means or psychotherapy. Animal studies have demonstrated that psychological stress increases Tc via mechanisms distinct from infectious fever (which requires proinflammatory mediators) and that the sympathetic nervous system, particularly β3-adrenoceptor-mediated non-shivering thermogenesis in brown adipose tissue, plays an important role in the development of psychological stress-induced hyperthermia. Acute psychological stress induces a transient, monophasic increase in Tc. In contrast, repeated stress induces anticipatory hyperthermia, reduces diurnal changes in Tc, or slightly increases Tc throughout the day. Chronically stressed animals also display an enhanced hyperthermic response to a novel stress, while past fearful experiences induce conditioned hyperthermia to the fear context. The high Tc that psychogenic fever patients develop may be a complex of these diverse kinds of hyperthermic responses.

Factitious psychogenic nonepileptic paroxysmal episodes

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Alissa Romano

2014-01-01

Full Text Available Mistaking psychogenic nonepileptic paroxysmal episodes (PNEPEs for epileptic seizures (ES is potentially dangerous, and certain features should alert physicians to a possible PNEPE diagnosis. Psychogenic nonepileptic paroxysmal episodes due to factitious seizures carry particularly high risks of morbidity or mortality from nonindicated emergency treatment and, often, high costs in wasted medical treatment expenditures. We report a case of a 28-year-old man with PNEPEs that were misdiagnosed as ES. The patient had been on four antiseizure medications (ASMs with therapeutic serum levels and had had multiple intubations in the past for uncontrolled episodes. He had no episodes for two days of continuous video-EEG monitoring. He then disconnected his EEG cables and had an episode of generalized stiffening and cyanosis, followed by jerking and profuse bleeding from the mouth. The manifestations were unusually similar to those of ES, except that he was clearly startled by spraying water on his face, while he was stiff in all extremities and unresponsive. There were indications that he had sucked blood from his central venous catheter to expel through his mouth during his PNEPEs while consciously holding his breath. Normal video-EEG monitoring; the patient's volitional and deceptive acts to fabricate the appearance of illness, despite pain and personal endangerment; and the absence of reward other than remaining in a sick role were all consistent with a diagnosis of factitious disorder.

Psychological therapy for psychogenic amnesia: Successful treatment in a single case study.

Science.gov (United States)

Cassel, Anneli; Humphreys, Kate

2016-01-01

Psychogenic amnesia is widely understood to be a memory impairment of psychological origin that occurs as a response to severe stress. However, there is a paucity of evidence regarding the effectiveness of psychological therapy approaches in the treatment of this disorder. The current article describes a single case, "Ben", who was treated with formulation-driven psychological therapy using techniques drawn from cognitive behavioural therapy (CBT) and acceptance and commitment therapy (ACT) for psychogenic amnesia. Before treatment, Ben exhibited isolated retrograde and anterograde memory impairments. He received 12 therapy sessions that targeted experiential avoidance followed by two review sessions, six weeks and five months later. Ben's retrograde and anterograde memory impairments improved following therapy to return to within the "average" to "superior" ranges, which were maintained at follow-up. Further experimental single case study designs and larger group studies are required to advance the understanding of the effectiveness and efficacy of psychological therapy for psychogenic amnesia.

[A Case of Psychogenic Tremor during Awake Craniotomy].

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Kujirai, Kazumasa; Kamata, Kotoe; Uno, Toshihiro; Hamada, Keiko; Ozaki, Makoto

2016-01-01

A 31-year-old woman with a left frontal and parietal brain tumor underwent awake craniotomy. Propofol/remifentanil general anesthesia was induced. Following craniotomy, anesthetic administrations ceased. The level of consciousness was sufficient and she was not agitated. However, the patient complained of nausea 70 minutes into the awake phase. Considering the adverse effects of antiemetics and the upcoming surgical strategy, we did not give any medications. Nausea disappeared spontaneously while the operation was suspended. When surgical intervention extended to the left caudate nucleus, involuntary movement, classified as a tremor, with 5-6 Hz frequency, abruptly occurred on her left forearm. The patient showed emotional distress. Tremor appeared on her right forearm and subsequently spread to her lower extremities. Intravenous midazolam and fentanyl could not reduce her psychological stress. Since the tremor disturbed microscopic observation, general anesthesia was induced. Consequently, the tremor disappeared and did not recur. Based on the anatomical ground and the medication status, her involuntary movement was diagnosed as psychogenic tremor. Various factors can induce involuntary movements. In fact, intraoperative management of nausea and vomiting takes priority during awake craniotomy, but we should be reminded that some antiemetics potentially induce involuntary movement that could be caused by surgery around basal ganglia.

Non-psychogenic polydipsia in 45-year-old man with primary hyperparathyroidism and recurrent bilateral nephrolithiasis

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Rahmat Cahyanur

2012-11-01

Full Text Available Non-psychogenic polydipsia with hyponatremia is a rare clinical presentation. Primary hyperparathyroidism is a disorder of calcium, phosphate, and bone metabolism caused by increased level of parathyroid hormone (PTH. It is estimated the incidence of primary hyperparathyroidism are 21.6 per 100,000 person a year. This case report describe a 45-year-old man presented with non-psychogenic polydipsia. This patient drank a lot of water out of the fear of recurrent kidney stones. He had history of recurrent nephrolithiasis with hypercalcemia. We investigate further the cause of hypercalcemia and we diagnosed primary hyperparathryoidism as the cause. (Med J Indones. 2012;21:230-4Keywords: Hyponatremia, non-psychogenic polydipsia, primary hyperparathyroidism

Parameter-Based Assessment of Disturbed and Intact Components of Visual Attention in Children with Developmental Dyslexia

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Bogon, Johanna; Finke, Kathrin; Schulte-Körne, Gerd; Müller, Hermann J.; Schneider, Werner X.; Stenneken, Prisca

2014-01-01

People with developmental dyslexia (DD) have been shown to be impaired in tasks that require the processing of multiple visual elements in parallel. It has been suggested that this deficit originates from disturbed visual attentional functions. The parameter-based assessment of visual attention based on Bundesen's (1990) theory of visual…

Emperor Napoleon Bonaparte: did he have seizures? Psychogenic or epileptic or both?

Science.gov (United States)

Hughes, John R

2003-12-01

Napoleon Bonaparte was a general in the French army at 24 years of age, later conquering most of Europe. He was one of the greatest military geniuses the world has ever known, but also an extremely intelligent individual. Did he have seizures? The evidence shows that he had both psychogenic and epileptic attacks. The psychogenic attacks were likely related to the tremendous stress in his life, and the epileptic seizures were the result of chronic uremia from a severe urethral stricture caused by gonorrhea that was transmitted from his wife, Empress Josephine.

Use of fiberoptic endoscopic evaluation of swallowing (FEES) in the management of psychogenic dysphagia in children.

Science.gov (United States)

Thottam, Prasad John; Silva, Rodrigo C; McLevy, Jennifer D; Simons, Jeffrey P; Mehta, Deepak K

2015-02-01

To describe the use of fiberoptic endoscopic evaluation of swallowing (FEES) as an adjunct in the management of children presenting with psychogenic dysphagia, defined as food avoidance and excessive fear of eating without identifiable anatomic or functional swallowing abnormalities. Case series of patients presenting to the otolaryngology clinic of a tertiary pediatric teaching hospital between 2007 and 2008 that were evaluated and managed with the utilization of FEES. The outcomes measured were age, gender, duration of symptoms, findings of FEES, additional work-up and resolution of symptoms at follow-up. Five patients (4 males, 1 female) with ages ranging from 5 to 13 years old (mean=8.6). The median duration of symptoms before presentation was 3 weeks. Four families described refusal of solids starting after choking episode and variable estimated weight loss (mean 2.8kg). One child presented with vague complaints of intermittent odynophagia and food refusal. Fiberoptic endoscopic evaluation of swallowing was performed on all patients. No abnormalities of the oropharyngeal swallow were appreciated. Additional management included different combinations of modified barium swallow study, esophagastroduodenoscopy (EGD), upper GI series, antibiotics, and psychotherapy. Mean follow-up with clinic visit was 4.2 months. Three of the five children reported complete resolution of symptoms after FEES at follow-up visit. Fiberoptic endoscopic evaluation of swallowing can be a useful management tool in children with psychogenic dysphagia as it provides direct visualization of the oropharyngeal swallowing mechanism. This can be used to provide visual reassure and biofeedback to patients and parents. Additional workup should be decided on an individual basis. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

[Indicators and factors of influence on the long-term follow-up of psychogenic diseases--a comparison of extreme groups].

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Franz, M; Schellberg, D; Schepank, H

1995-02-01

The present investigation aimed at the identification of possible indicators of course, predictors, and etiologically relevant factors of psychogenic diseases. According to their complaints a sample of probands suffering from psychogenic impairment of medium degree (n = 240) was chosen out of a representative sample of an urban adult population (n = 528). This procedure should ensure a relatively high intraindividual variance of course of the criterion, since a sufficient variability of course seems improbable with chronic and severe psychogenic impaired or stabile healthy probands. Within 10 years the sample was investigated three times by psychodynamically trained physicians and psychologists. By means of cluster analysis the sample was subdivided in different types of course of psychogenic impairment. Both extreme types of course-the probands who showed the most positive and the most negative spontaneous longterm course-were investigated univariately and by means of a multivariate discriminant analysis with regard to potentially course determining variables. It became obvious that personality variables and conditions of early childhood considerably influenced the spontaneous longterm course of psychogenic impairment.

Recognition of psychogenic non-epileptic seizures: a curable neurophobia?

LENUS (Irish Health Repository)

O'Sullivan, S S

2013-02-01

Diagnosing psychogenic non-epileptic seizures (PNES) remains challenging. The majority of \\'PNES status\\' cases are likely to be seen in the emergency department or similar non-specialised units, where patients are initially assessed and managed by physicians of varying expertise in neurology.

Psychogenic chemical sensitivity: psychogenic pseudoseizures elicited by provocation challenges with fragrances.

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Staudenmayer, H; Kramer, R E

1999-08-01

A middle-aged woman with a 10-year history of disability attributed to chemical sensitivities complained that exposure to specific fragrances immediately elicited seizures. Video-EEG monitoring was performed in a hospital neurodiagnostic laboratory during provocative challenge studies employing fragrances identified by the patient as reliably inducing symptoms. The baseline clinical EEG was normal. Immediately after each provocation with air deodorant and perfume, she consistently showed both generalized tonic/clonic and multifocal myoclonic jerking, at times was nonresponsive, spoke with slurred speech, and complained of right-sided paralysis and lethargy. None of these events were associated with any EEG abnormalities. Psychological assessment (MMPI-2, MCMI-II) revealed personality traits that predisposed her to somatization and beliefs about environmental sensitivities. The convulsions were a manifestation of psychogenic pseudoseizures that had been iatrogenically reinforced.

Comprehensive Management of Psychogenic Dysphonia: A Case Illustration

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Sudhir, Paulomi M.; Chandra, Prabha S.; Shivashankar, N.; Yamini, B. K.

2009-01-01

Psychogenic dysphonia refers to the loss of voice, in the absence of apparent structural or neurological pathology. It is a disorder seen more often in women and is usually associated with significant life events and emotional difficulties that may lead to conflict over speaking. Therapeutic interventions in voice disorders recommend the adoption…

Metabolic Hyperactivity of the Medial Posterior Parietal Lobes in Psychogenic Tremor

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Peter Hedera

2012-05-01

Full Text Available Background: The pathophysiology of psychogenic movement disorders, including psychogenic tremor (PT, is only emerging. Case Report: This is a single case report of a patient who met diagnostic criteria for PT. He underwent positron emission tomography (PET of brain with 18F-deoxyglucose at resting state. His PET study showed symmetrically increased 18F-deoxyglucose uptake in both posterior medial parietal lobes. There was no corresponding abnormality on structural imaging. Discussion: Hypermetabolism of the medial aspects of posterior parietal lobes bilaterally may reflect abnormal activity of sensory integration that is important in the pathogenesis of PT. This further supports the idea that non-organic movement disorders may be associated with detectable functional brain abnormalities.

Psychogenic nonepileptic seizures and chronic pain: a retrospective case-controlled study.

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Gazzola, Deana M; Carlson, Chad; Rugino, Angela; Hirsch, Scott; Starner, Karen; Devinsky, Orrin

2012-12-01

Psychogenic nonepileptic seizures (PNES) can be challenging to diagnose, but certain clinical features can help to distinguish PNES from epileptic seizures. The purpose of this study is to assess chronic pain and prescribed pain medication use in PNES patients. A case-controlled, retrospective analysis was performed examining pain medication use in 85 PNES patients versus an active control group of 85 patients with idiopathic generalized epilepsy (IGE). Chronic pain was more frequent among PNES patients (N=40) than active controls (N=10) (pseizures raises the possibility of PNES. Among patients with PNES and chronic pain, a psychogenic etiology for pain and non-opiate pain management strategies should be considered. Copyright © 2012 Elsevier Inc. All rights reserved.

Psychogenic Polydipsia: The Result, or Cause of, Deteriorating Psychotic Symptoms? A Case Report of the Consequences of Water Intoxication

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Melissa Gill

2015-01-01

Full Text Available Water intoxication is a rare condition characterised by overconsumption of water. It can occur in athletes engaging in endurance sports, users of MDMA (ecstasy, and patients receiving total parenteral nutrition. This case outlines water intoxication in a patient with psychogenic polydipsia. When the kidney’s capacity to compensate for exaggerated water intake is exceeded, hypotonic hyperhydration results. Consequences can involve headaches, behavioural changes, muscular weakness, twitching, vomiting, confusion, irritability, drowsiness, and seizures. Cerebral oedema can lead to brain damage and eventual death. In this case, psychogenic polydipsia led to significant hyponatraemia, cerebral oedema, and tonic-clonic seizures. Differential diagnoses for hyponatraemia are outlined. The aetiology of psychogenic polydipsia is uncertain, but postulated hypotheses are explored. Psychogenic polydipsia occurs in up 20% of psychiatric patients and this case serves to remind us to be cognizant of water overconsumption.

Psychogenic urine retention during doping controls

DEFF Research Database (Denmark)

Elbe, Anne-Marie; Schlegel, Marius M.; Brand, Ralf

2012-01-01

relation to recovery, performance, and self-perception of professionalism and athletic excellence. Furthermore, a scale developed especially for the close description and measurement of PURD is presented. A questionnaire was used for measuring paruresis. The results are based on two online and one paper...... and pencil study involving 222 German-speaking athletes from various sports. The results indicate that 60% of these athletes have experienced psychogenic urine retention during doping controls, with only 39% of them showing symptoms of paruresis. PURD impacts athlete recovery and self-perception...

Basal hypercortisolism and trauma in patients with psychogenic nonepileptic seizures

NARCIS (Netherlands)

Bakvis, P.; Spinhoven, P.; Giltay, E.J.; Kuyk, J.; Edelbroek, P.M.; Zitman, F.G.; Roelofs, K.

2010-01-01

Purpose: Several studies have indicated that psychogenic nonepileptic seizures (PNES) are associated with psychological trauma, but only a few studies have examined the associations with neurobiologic stress systems, such as the hypothalamus-pituitary-adrenal (HPA) axis and its end-product cortisol.

Distonia psicogênica: relato de dois casos Psychogenic dystonia: report of two cases

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ANTONIO PEDRO VARGAS

2000-06-01

Full Text Available Desordens de movimento raramente podem ser devidas a distúrbios psiquiátricos. A distonia psicogênica caracteriza-se pela inconsistência dos achados, presença de fatores precipitantes, manifestar-se inicialmente nos membros inferiores, associar-se a dor, a outros movimentos anormais incaracterísticos e a somatizações múltiplas. Descrevemos duas pacientes com diagnóstico de distonia psicogênica clinicamente estabelecida. Paciente 1, feminina, apresentou episódio súbito de perda de força dos quatro membros, evoluiu com distonia nos pés, laterocolo alternante, tremor generalizado, irregular, e hipertonia dos membros inferiores que desapareciam a distração; a avaliação psicológica evidenciou depressão, hipocondria, transtorno obsessivo. Paciente 2, feminina, há nove anos começou a ter tremor irregular nos membros inferiores, que desaparecia com a distração, e distonia no pé esquerdo associada a dor; progressivamente perdeu a marcha; a avaliação psicológica revelou comportamento infantilizado, com baixa tolerância a frustração, impulsividade e auto-agressão. Os exames complementares de ambas não mostraram alterações e a resposta ao tratamento farmacológico foi nula. Distonia raramente é de origem psicogênica. A inconstância e a incongruência com o quadro clássico, associadas a outras somatizações ou a distúrbios psiquiátricos, sugerem o diagnóstico.Movement disorders have rarely been the result of psychiatric disturbances. Psychogenic dystonia is caracterized by inconsistent findings, a known precipitant factor, onset in legs, pain , multiple somatizations and incongruent association with other movement disorders. We report two patients with clinically established psychogenic dystonia. Patient 1: a female that presented sudden loss of strength in her four limbs; she developed feet dystonia, alternant laterocollis, generalized and irregular tremor, and limb hypertonia that disappeared with distraction

Psychogenic Foreign Accent Syndrome: a new case

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Stefanie eKeulen

2016-04-01

Full Text Available This paper presents the case of a 33-year-old, right-handed, French-speaking Belgian lady who was involved in a car accident as a pedestrian. Six months after the incident she developed a German/Flemish-like accent. The patient’s medical history, the onset of the FAS and the possible psychological causes of the accent change are analyzed. Relevant neuropsychological, neurolinguistic and psychodiagnostic test results are presented and discussed. The psychodiagnostic interview and testing will receive special attention, because these have been underreported in previous FAS case reports. Furthermore, an accent rating experiment was carried out in order to assess the foreign quality of the patient’s speech. Pre- and post-morbid spontaneous speech samples were analyzed phonetically to identify the pronunciation characteristics associated with this type of FAS. Several findings were considered essential in the diagnosis of psychogenic FAS: the psychological assessments as well as the clinical interview confirmed the presence of psychological problems, while neurological damage was excluded by means of repeated neuroimaging and neurological examinations. The type and nature of the speech symptoms and the accent fluctuations associated with the patient's psychological state cannot be explained by a neurological disorder. Moreover, the indifference of the patient towards her condition may also suggest a psychogenic etiology, as the opposite is usually observed in neurogenic FAS patients.

Escitalopram for Psychogenic Nausea and Vomiting: A Report of Two Cases

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Wen-Yu Hsu

2011-01-01

Full Text Available Psychogenic nausea and vomiting is defined as vomiting without any obvious organic pathology or vomiting with a psychological etiology. The treatment for such a condition is a challenge in clinical practice. The first patient was a 46-year-old married factory worker who was repeatedly hospitalized for recurring bouts of nausea and vomiting. After consultation, she was diagnosed with major depressive disorder. The frequency of nausea and vomiting decreased after treatment with daily doses of 10–20 mg escitalopram. The second patient was a 37-year-old married teacher who had bouts of nausea and vomiting and was also hospitalized repeatedly. She was diagnosed with mixed anxiety–depressive disorder. After treatment with 10 mg/day escitalopram, her episodes of nausea and vomiting decreased. Escitalopram may be an effective treatment for psychogenic nausea and vomiting associated with depression.

A psychogenic dystonia perfect responsive to antidepressant treatment.

OpenAIRE

Volkan Solmaz; Durdane Aksoy; Betul Cevik; Semiha Gulsum Kurt; Elmas Pekdas; Sema inanir

2014-01-01

After ruling out of organic causes, movement disorders are named as psychogenic movement disorders, it can mimic perfectly Organic movement disorders, but with a good history, clinical observations and detailed examination is very helpful in the diagnosis of this disease. In here we will present a 15 years old male patient, he was complaining of urinary incontinence at night, emerging dystonic posture especially in crowded environments, eating, and during activities that require attention, fo...

Psychogenic Stress in Hospitalized Dogs: Cross Species Comparisons, Implications for Health Care, and the Challenges of Evaluation

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Jessica P. Hekman

2014-06-01

Full Text Available Evidence to support the existence of health consequences of psychogenic stress has been documented across a range of domestic species. A general understanding of methods of recognition and means of mitigation of psychogenic stress in hospitalized animals is arguably an important feature of the continuing efforts of clinicians to improve the well-being and health of dogs and other veterinary patients. The intent of this review is to describe, in a variety of species: the physiology of the stress syndrome, with particular attention to the hypothalamic-pituitary-adrenal axis; causes and characteristics of psychogenic stress; mechanisms and sequelae of stress-induced immune dysfunction; and other adverse effects of stress on health outcomes. Following that, we describe general aspects of the measurement of stress and the role of physiological measures and behavioral signals that may predict stress in hospitalized animals, specifically focusing on dogs.

The Dancing Manias: Psychogenic Illness as a Social Phenomenon.

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Lanska, Douglas J

2018-01-01

The dancing mania erupted in the 14th century in the wake of the Black Death, and recurred for centuries in central Europe - particularly Germany, the Netherlands, and Belgium - finally abating in the early 17th century. The term "dancing mania" was derived from "choreomania," a concatenation of choros (dance) and mania (madness). A variant, tarantism, was prevalent in southern Italy from the 15th to the 17th centuries, and was attributed at the time to bites from the tarantula spider. Affected individuals participated in continuous, prolonged, erratic, often frenzied and sometimes erotic, dancing. In the 14th century, the dancing mania was linked to a corruption of the festival of St. John's Day by ancient pagan customs, but by the 16th century it was commonly considered an ordeal sent by a saint, or a punishment from God for people's sins. Consequently, during outbreaks in the 14th and 15th centuries, the dancing mania was considered an issue for magistrates and priests, not physicians, even though the disorder proved intractable to decrees and exorcisms. However, in the 16th century Paracelsus discounted the idea that the saints caused or interceded in the cure of the dancing mania; he instead suggested a psychogenic or malingered etiology, and this reformulation brought the dancing mania within the purview of physicians. Paracelsus advocated various mystical, psychological, and pharmacological approaches, depending on the presumptive etiologic factors with individual patients. Only music provided any relief for tarantism. Later authors suggested that the dancing mania was a mass stress-induced psychosis, a mass psychogenic illness, a culturally determined form of ritualized behavior, a manifestation of religious ecstasy, or even the result of food poisoning caused by the toxic and psychoactive chemical products of ergot fungi. In reality, dancing manias did not have a single cause, but component causes likely included psychogenic illness, malingering, and

Rethinking the Psychogenic Model of Complex Regional Pain Syndrome: Somatoform Disorders and Complex Regional Pain Syndrome

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Hill, Renee J.; Chopra, Pradeep; Richardi, Toni

2012-01-01

Abstract Explaining the etiology of Complex Regional Pain Syndrome (CRPS) from the psychogenic model is exceedingly unsophisticated, because neurocognitive deficits, neuroanatomical abnormalities, and distortions in cognitive mapping are features of CRPS pathology. More importantly, many people who have developed CRPS have no history of mental illness. The psychogenic model offers comfort to physicians and mental health practitioners (MHPs) who have difficulty understanding pain maintained by newly uncovered neuro inflammatory processes. With increased education about CRPS through a biopsychosocial perspective, both physicians and MHPs can better diagnose, treat, and manage CRPS symptomatology. PMID:24223338

Trauma, stress, and preconscious threat processing in patients with psychogenic nonepileptic seizures

NARCIS (Netherlands)

Bakvis, P.; Roelofs, K.; Kuyk, J.; Edelbroek, P.M.; Swinkels, W.A.M.; Spinhoven, P.

2009-01-01

Psychogenic nonepileptic seizures (PNES) have long been considered as paroxysmal dissociative symptoms characterized by an alteration of attentional functions caused by severe stress or trauma. Although interpersonal trauma is common in PNES, the proposed relation between trauma and attentional

[Psychogenic paroxysmal disorders in children].

Science.gov (United States)

Mulas, F; Morant, A

Paroxystic psychic disorders which imitate organic disorders of the nervous system may have peripheral effects, present as changes in level of consciousness or appear as paroxystic behaviour changes. The types of crises of psychological origin are: tantrums, panic attacks, crises of psychopathic rage, onanism or masturbation, epileptic pseudocrises or pseudoconvulsions and Munchausen's syndrome. In general psychic crises are not frequent in infancy: tantrums are commoner in small children and the other conditions usually occur after puberty or during adolescence. The anamnesis is the most important factor in the correct diagnosis of psychogenic paroxystic disorders. Complementary studies are done in doubtful cases, to rule out different pathological processes which might be causing the paroxystic disorder. Amongst these investigations, we emphasize the importance of the video-EEG for differential diagnosis of paroxystic disorders in children.

Mass Psychogenic Illness: Demography and Symptom Profile of an Episode

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Binoy Krishna Tarafder

2016-01-01

Full Text Available Background. Mass psychogenic illness has been a recurrent phenomenon in Bangladesh over recent times. Objectives. This study was aimed at investigating the demographic characteristics and symptom profile of an outbreak of mass psychogenic illness occurring in a girls’ high school. Methods and Materials. In 14 April 2013, a total of 93 students of a girls’ high school suddenly developed various symptoms following intake of tiffin cake which resulted in panic and hospital admission. A descriptive, cross-sectional observational survey was done to define various characteristics of the outbreak. Results. No organic explanation for the reported illnesses was found. 93 female students were included who were hospitalized during the incident. Trigger factor was found in 98% of students. Most of the students were 13 years old. Average interval between exposure to the trigger and onset of symptoms was 151.5 minutes. Commonest symptoms were abdominal pain (83%, headache (73%, chest pain (69%, body ache (63%, nausea (69%, and generalized weakness and fatigue (61%. Hospital stay following the incident was about 12 hours on average. Conclusion. To avoid unnecessary panic in the community a prompt, coordinated response is important in resolving widespread community anxiety surrounding these episodes.

Mass Psychogenic Illness: Demography and Symptom Profile of an Episode

Science.gov (United States)

Tarafder, Binoy Krishna; Khan, Mohammad Ashik Imran; Islam, Md. Tanvir; Mahmud, Sheikh Abdullah Al; Sarker, Md. Humayun Kabir; Faruq, Imtiaz; Miah, Md. Titu; Arafat, S. M. Yasir

2016-01-01

Background. Mass psychogenic illness has been a recurrent phenomenon in Bangladesh over recent times. Objectives. This study was aimed at investigating the demographic characteristics and symptom profile of an outbreak of mass psychogenic illness occurring in a girls' high school. Methods and Materials. In 14 April 2013, a total of 93 students of a girls' high school suddenly developed various symptoms following intake of tiffin cake which resulted in panic and hospital admission. A descriptive, cross-sectional observational survey was done to define various characteristics of the outbreak. Results. No organic explanation for the reported illnesses was found. 93 female students were included who were hospitalized during the incident. Trigger factor was found in 98% of students. Most of the students were 13 years old. Average interval between exposure to the trigger and onset of symptoms was 151.5 minutes. Commonest symptoms were abdominal pain (83%), headache (73%), chest pain (69%), body ache (63%), nausea (69%), and generalized weakness and fatigue (61%). Hospital stay following the incident was about 12 hours on average. Conclusion. To avoid unnecessary panic in the community a prompt, coordinated response is important in resolving widespread community anxiety surrounding these episodes. PMID:27294104

Psychogenic Explanations of Physical Illness: Time to Examine the Evidence.

Science.gov (United States)

Wilshire, Carolyn E; Ward, Tony

2016-09-01

In some patients with chronic physical complaints, detailed examination fails to reveal a well-recognized underlying disease process. In this situation, the physician may suspect a psychological cause. In this review, we critically evaluated the evidence for this causal claim, focusing on complaints presenting as neurological disorders. There were four main conclusions. First, patients with these complaints frequently exhibit psychopathology but not consistently more often than patients with a comparable "organic" diagnosis, so a causal role cannot be inferred. Second, these patients report a high incidence of adverse life experiences, but again, there is insufficient evidence to indicate a causal role for any particular type of experience. Third, although psychogenic illnesses are believed to be more responsive to psychological interventions than comparable "organic" illnesses, there is currently no evidence to support this claim. Finally, recent evidence suggests that biological and physical factors play a much greater causal role in these illnesses than previously believed. We conclude that there is currently little evidential support for psychogenic theories of illness in the neurological domain. In future research, researchers need to take a wider view concerning the etiology of these illnesses. © The Author(s) 2016.

Vulnerability to psychogenic non-epileptic seizures is linked to low neuropeptide Y levels

DEFF Research Database (Denmark)

Winterdahl, Michael; Miani, Alessandro; Vercoe, Moana

2017-01-01

Psychogenic non-epileptic seizures (PNES) is a conversion disorder that reflects underlying psychological distress. Female patients with PNES often present with a history of prolonged stressors, especially sexual abuse. In the current study, we studied the relationship between neuropeptide Y (NPY...

Brain networks during free viewing of complex erotic movie: new insights on psychogenic erectile dysfunction.

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Nicoletta Cera

Full Text Available Psychogenic erectile dysfunction (ED is defined as a male sexual dysfunction characterized by a persistent or recurrent inability to attain adequate penile erection due predominantly or exclusively to psychological or interpersonal factors. Previous fMRI studies were based on the common occurrence in the male sexual behaviour represented by the sexual arousal and penile erection related to viewing of erotic movies. However, there is no experimental evidence of altered brain networks in psychogenic ED patients (EDp. Some studies showed that fMRI activity collected during non sexual movie viewing can be analyzed in a reliable manner with independent component analysis (ICA and that the resulting brain networks are consistent with previous resting state neuroimaging studies. In the present study, we investigated the modification of the brain networks in EDp compared to healthy controls (HC, using whole-brain fMRI during free viewing of an erotic video clip. Sixteen EDp and nineteen HC were recruited after RigiScan evaluation, psychiatric, and general medical evaluations. The performed ICA showed that visual network (VN, default-mode network (DMN, fronto-parietal network (FPN and salience network (SN were spatially consistent across EDp and HC. However, between-group differences in functional connectivity were observed in the DMN and in the SN. In the DMN, EDp showed decreased connectivity values in the inferior parietal lobes, posterior cingulate cortex and medial prefrontal cortex, whereas in the SN decreased and increased connectivity was observed in the right insula and in the anterior cingulate cortex respectively. The decreased levels of intrinsic functional connectivity principally involved the subsystem of DMN relevant for the self relevant mental simulation that concerns remembering of past experiences, thinking to the future and conceiving the viewpoint of the other's actions. Moreover, the between group differences in the SN nodes

Brain networks during free viewing of complex erotic movie: new insights on psychogenic erectile dysfunction.

Science.gov (United States)

Cera, Nicoletta; Di Pierro, Ezio Domenico; Ferretti, Antonio; Tartaro, Armando; Romani, Gian Luca; Perrucci, Mauro Gianni

2014-01-01

Psychogenic erectile dysfunction (ED) is defined as a male sexual dysfunction characterized by a persistent or recurrent inability to attain adequate penile erection due predominantly or exclusively to psychological or interpersonal factors. Previous fMRI studies were based on the common occurrence in the male sexual behaviour represented by the sexual arousal and penile erection related to viewing of erotic movies. However, there is no experimental evidence of altered brain networks in psychogenic ED patients (EDp). Some studies showed that fMRI activity collected during non sexual movie viewing can be analyzed in a reliable manner with independent component analysis (ICA) and that the resulting brain networks are consistent with previous resting state neuroimaging studies. In the present study, we investigated the modification of the brain networks in EDp compared to healthy controls (HC), using whole-brain fMRI during free viewing of an erotic video clip. Sixteen EDp and nineteen HC were recruited after RigiScan evaluation, psychiatric, and general medical evaluations. The performed ICA showed that visual network (VN), default-mode network (DMN), fronto-parietal network (FPN) and salience network (SN) were spatially consistent across EDp and HC. However, between-group differences in functional connectivity were observed in the DMN and in the SN. In the DMN, EDp showed decreased connectivity values in the inferior parietal lobes, posterior cingulate cortex and medial prefrontal cortex, whereas in the SN decreased and increased connectivity was observed in the right insula and in the anterior cingulate cortex respectively. The decreased levels of intrinsic functional connectivity principally involved the subsystem of DMN relevant for the self relevant mental simulation that concerns remembering of past experiences, thinking to the future and conceiving the viewpoint of the other's actions. Moreover, the between group differences in the SN nodes suggested a

Mass psychogenic illness after vaccination.

Science.gov (United States)

Clements, C John

2003-01-01

When vaccines are administered to groups, the physical reactions of the recipients may be similar, causing a form of mass reaction, the mechanism for which is the same as that for mass reactions from other causes. These phenomena have been categorised as mass psychogenic illness (MPI), and have been defined as the collective occurrence of a constellation of symptoms suggestive of organic illness but without an identified cause in a group of people with shared beliefs about the cause of the symptom(s). A review of the literature shows that such outbreaks have been reported in differing cultural and environmental settings including developing and industrialised countries, in the work place, on public transport, in schools, and the military. The perceived threats have been against agents such as food poisoning, fire and toxic gases. Whatever the place or perceived threat, the response seems to be similar. The symptoms generally included headache, dizziness, weakness, and loss of consciousness. Once under way, MPIs are not easy to stop. Incidents reported in the literature show that they can quickly gather momentum and can be amplified by the press who disseminate information rapidly, escalating the events. Management of such mass events can be extremely difficult. Should the public health official in charge continue to try and determine the cause, or should this person call off the entire investigation? It is suggested here that once vaccines are identified as a probable cause of the phenomenon, a dismissive approach may actually be harmful. Unless the spokesperson has already earned a high level of trust, the public are not likely to be convinced easily that nothing was wrong with the vaccine until it has been tested. An increased awareness of MPIs on the part of organisers of future mass vaccination campaigns seems appropriate. Immunisation managers should be aware that mass immunisation campaigns could generate such mass reactions. It is therefore essential that

Clinical Features of Pregnancy-associated Retinal and Choroidal Diseases Causing Acute Visual Disturbance.

Science.gov (United States)

Park, Young Joo; Park, Kyu Hyung; Woo, Se Joon

2017-08-01

To report clinical features of patients with retinal and choroidal diseases presenting with acute visual disturbance during pregnancy. In this retrospective case series, patients who developed acute visual loss during pregnancy (including puerperium) and visited a tertiary hospital from July 2007 to June 2015, were recruited by searching electronic medical records. Patients were categorized according to the cause of visual loss. Clinical features and required diagnostic modalities were analyzed in the retinal and choroidal disease group. Acute visual loss occurred in 147 patients; 49 (38.9%) were classified into the retinal and choroidal group. The diagnoses included central serous chorioretinopathy (22.4%), hypertensive retinopathy with or without pre-eclampsia (22.4%), retinal tear with or without retinal detachment (18.4%), diabetic retinopathy progression (10.2%), Vogt-Koyanagi-Harada disease (4.1%), retinal artery occlusion (4.1%), multiple evanescent white dot syndrome (4.1%), and others (14.3%). Visual symptoms first appeared at gestational age 25.9 ± 10.3 weeks. The initial best-corrected visual acuity (BCVA) was 0.27 ± 0.39 logarithm of the minimum angle of resolution (logMAR); the final BCVA after delivery improved to 0.13 ± 0.35 logMAR. Serious visual deterioration (BCVA worth than 20 / 200) developed in two patients. Differential diagnoses were established with characteristic fundus and spectral-domain optical coherence tomography findings in all cases. In pregnant women with acute visual loss, retinal and choroidal diseases are common and could be vision threatening. Physicians should be aware of pregnancy-associated retinal and choroidal diseases and their clinical features. The differential diagnosis can be established with non-invasive techniques. © 2017 The Korean Ophthalmological Society

Thermogenic and psychogenic recruitment of human eccrine sweat glands: Variations between glabrous and non-glabrous skin surfaces.

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Machado-Moreira, Christiano A; Taylor, Nigel A S

2017-04-01

Human eccrine sweat-gland recruitment and secretion rates were investigated from the glabrous (volar) and non-glabrous hand surfaces during psychogenic (mental arithmetic) and thermogenic stimuli (mild hyperthermia). It was hypothesised that these treatments would activate glands from both skin surfaces, with the non-thermal stimulus increasing secretion rates primarily by recruiting more sweat glands. Ten healthy men participated in two seated, resting trials in temperate conditions (25-26°C). Trials commenced under normothermic conditions during which the first psychogenic stress was applied. That was followed by passive heating (0.5°C mean body temperature elevation) and thermal clamping, with a second cognitive challenge then applied. Sudomotor activity was evaluated from both hands, with colourimetry used to identify activated sweat glands, skin conductance to determine the onset of precursor sweating and ventilated sweat capsules to measure rates of discharged sweating. From glandular activation and sweat rate data, sweat-gland outputs were derived. These psychogenic and thermogenic stimuli activated sweat glands from both the glabrous and non-glabrous skin surfaces, with the former dominating at the glabrous skin and the latter at the non-glabrous surface. Indeed, those stimuli individually accounted for ~90% of the site-specific maximal number of activated sweat glands observed when both stimuli were simultaneously applied. During the normothermic psychological stimulation, sweating from the glabrous surface was elevated via a 185% increase in the number of activated glands within the first 60s. The hypothetical mechanism for this response may involve the serial activation of additional eccrine sweat glands during the progressive evolution of psychogenic sweating. Copyright © 2017 Elsevier Ltd. All rights reserved.

[P300 potential in chldren with psychogenic nonepileptic events and tension headache].

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Steczkowska, Małgorzata; Stolarska-Weryńska, Urszula; Fiederer, Krystyna; Kaciński, Marek

2016-01-01

Psychotherapy is being used as the primary treatment in nonepileptic psychogenic seizures and tension headaches in children. Children's intelectual functioning is related to certain endogenous neurophysiological parameters. The goal of this study was to establish whether the endogenous potential P300 is different in children with nonepileptic psychogenic events and with tension headaches, and whether it changes under the influence of the cognitive-behavioral psychotherapy. The study included a group of 47 children: 20 with nonepileptic psychogenic seizures (18 girls and 2 boys), aged 11.09-17.11 years, and 27 children with tension headache (25 girls and 2 boys), aged 10.11-17.11 years. The P300 potential was induced using an auditory stimulus. The reaction time, the amount of mistakes and the percentage of attention focus was measured in all children. All children attended 8-10 psychotherapy sessions. The P300 potential was registered before and after the course of therapy, and additionally in both cycles also after a 3 minutes hyperventilation. Medium P300 parameters were closer to normal in the group of children with tension headaches rather than in the group with nonepileptic seizures. The shorter was the reaction time in the first measurement, the higher the attention score and the shorter the reaction time in the second measurement - this was visible in the results of children with nonepileptic seizures, in contrast to children with tension headaches. The use of hyperventilation caused a noticeable extension of the reaction time in the P300 measurement, with other components unchanged (mistake count and percentage of attention focus). The endogenous potential P300 does vary, although on a statistically insignificant level, in groups of children with tension headaches and nonepileptic seizures.

Early Motor Unit Disease Masquerading as Psychogenic Breathy Dysphonia: A Clinical Case Presentation

Science.gov (United States)

Aronson, Arnold E.

1971-01-01

Presented is a study of a 20-year-old girl with mild, breathy dysphonia, previously diagnosed as psychogenic. In actuality, her voice change was a sign of early myasthenia gravis. It is pointed out that voice changes can be a first and only sign of early neurologic disease. (Author/KW)

Diffuse malignant lymphoma type B with optic chiasm infiltration, visual disturbances, hypopituitarism, hyperprolactinaemia and diabetes insipidus. Case report and literature review

International Nuclear Information System (INIS)

Bolanowski, M.; Kuliszkiewicz-Janus, M.; Sokolska, V.

2006-01-01

The case is reported of a 55-year-old man with diffuse malignant lymphoma type B associated with transient optic chiasm infiltration and visual disturbances but with persistent hypopituitarism, hyperprolactinaemia and diabetes insipidus. The patient was administered chemotherapy and radiotherapy. Repeated MR and CT scans showed optic chiasm infiltration, which disappeared in the course of the chemotherapy but then recurred, changed its appearance and finally disappeared again. In the meantime visual disturbances occurred and disappeared during the therapy. Hypopituitarism, diabetes insipidus and hyperprolactinaemia were diagnosed and replacement therapy was administered. Later on abdominal pain occurred, and a CT scan revealed bilateral kidney masses and enlarged retroperitoneal lymph nodes. These were diffuse malignant lymphoma with regional lymphonodulitis in histology. Finally, hydrothorax and hydroretroperitoneum were diagnosed. The patient died as a result of systemic complications of the disease. The length of survival time documented following the hypothalamochiasmatic infiltration and diagnosis of lymphoma makes the case an unusual one for patients with CNS lymphoma. Hormonal disturbances accompanying the suprasellar region infiltration are very important from the practical point of view. (author)

Cognitive-behavioral therapy for psychogenic nonepileptic seizures

Science.gov (United States)

Goldstein, L.H.; Chalder, T.; Chigwedere, C.; Khondoker, M.R.; Moriarty, J.; Toone, B.K.; Mellers, J.D.C.

2010-01-01

Objective: To compare cognitive-behavioral therapy (CBT) and standard medical care (SMC) as treatments for psychogenic nonepileptic seizures (PNES). Methods: Our randomized controlled trial (RCT) compared CBT with SMC in an outpatient neuropsychiatric setting. Sixty-six PNES patients were randomized to either CBT (plus SMC) or SMC alone, scheduled to occur over 4 months. PNES diagnosis was established by video-EEG telemetry for most patients. Exclusion criteria included comorbid history of epilepsy, <2 PNES/month, and IQ <70. The primary outcome was seizure frequency at end of treatment and at 6-month follow-up. Secondary outcomes included 3 months of seizure freedom at 6-month follow-up, measures of psychosocial functioning, health service use, and employment. Results: In an intention-to-treat analysis, seizure reduction following CBT was superior at treatment end (group × time interaction p < 0.0001; large to medium effect sizes). At follow-up, the CBT group tended to be more likely to have experienced 3 months of seizure freedom (odds ratio 3.125, p = 0.086). Both groups improved in some health service use measures and on the Work and Social Adjustment Scale. Mood and employment status showed no change. Conclusions: Our findings suggest that cognitive-behavioral therapy is more effective than standard medical care alone in reducing seizure frequency in PNES patients. Classification of evidence: This study provides Class III evidence that CBT in addition to SMC, as compared to SMC alone, significantly reduces seizure frequency in patients with PNES (change in median monthly seizure frequency: baseline to 6 months follow-up, CBT group, 12 to 1.5; SMC alone group, 8 to 5). GLOSSARY AED = antiepileptic drug; CBT = cognitive-behavioral therapy; CI = confidence interval; DSM-IV = Diagnostic and Statistical Manual of Mental Disorders, 4th edition; HADS = Hospital Anxiety and Depression Scale; IQR = interquartile range; ITT = intention-to-treat; OR = odds ratio; PNES

Functional (psychogenic) stereotypies.

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Baizabal-Carvallo, José Fidel; Jankovic, Joseph

2017-07-01

Functional (psychogenic) movement disorders (FMDs) may present with a broad spectrum of phenomenology including stereotypic movements. We aimed to characterize the phenomenology of functional stereotypies and compare these features with those observed in 65 patients with tardive dyskinesia (TD). From a cohort of 184 patients with FMDs, we identified 19 (10.3%) with functional stereotypies (FS). There were 15 women and 4 men, with a mean age at onset of 38.6 ± 17.4 years. Among the patients with FS, there were 9 (47%) with orolingual dyskinesia/stereotypy, 9 (47%) with limb stereotypies, 6 (32%) with trunk stereotypies, and 2 (11%) with respiratory dyskinesia as part of orofacial-laryngeal-trunk stereotypy. These patients showed signs commonly seen in FMDs such as sudden onset (84%), prominent distractibility (58%), and periods of unexplained improvement (84%) that were not reported in patients with TD. Besides a much lower frequency of exposure to potential offending drugs, patients with FS differed from those with classic TD by a younger age at onset, lack of self-biting, uncommon chewing movements, more frequent lingual movements without mouth dyskinesia, and associated functional tremor and abnormal speech. Lack of self-biting showed the highest sensitivity (1.0) and abnormal speech showed the highest specificity (0.9) for the diagnosis of functional orolingual dyskinesia. FS represent part of the clinical spectrum of FMDs. Clinical and demographic features are helpful in distinguishing patients with FS from those with TD.

Psychogenic stuttering and other acquired nonorganic speech and language abnormalities.

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Binder, Laurence M; Spector, Jack; Youngjohn, James R

2012-08-01

Three cases are presented of peculiar speech and language abnormalities that were evaluated in the context of personal injury lawsuit or workers compensation claims of brain dysfunction after mild traumatic brain injuries. Neuropsychological measures of effort and motivation showed evidence of suboptimal motivation or outright malingering. The speech and language abnormalities of these cases probably were not consistent with neurogenic features of dysfluent speech including stuttering or aphasia. We propose that severe dysfluency or language abnormalities persisting after a single, uncomplicated, mild traumatic brain injury are unusual and should elicit suspicion of a psychogenic origin.

Disturbance of visual search by stimulating to posterior parietal cortex in the brain using transcranial magnetic stimulation

Science.gov (United States)

Iramina, Keiji; Ge, Sheng; Hyodo, Akira; Hayami, Takehito; Ueno, Shoogo

2009-04-01

In this study, we applied a transcranial magnetic stimulation (TMS) to investigate the temporal aspect for the functional processing of visual attention. Although it has been known that right posterior parietal cortex (PPC) in the brain has a role in certain visual search tasks, there is little knowledge about the temporal aspect of this area. Three visual search tasks that have different difficulties of task execution individually were carried out. These three visual search tasks are the "easy feature task," the "hard feature task," and the "conjunction task." To investigate the temporal aspect of the PPC involved in the visual search, we applied various stimulus onset asynchronies (SOAs) and measured the reaction time of the visual search. The magnetic stimulation was applied on the right PPC or the left PPC by the figure-eight coil. The results show that the reaction times of the hard feature task are longer than those of the easy feature task. When SOA=150 ms, compared with no-TMS condition, there was a significant increase in target-present reaction time when TMS pulses were applied. We considered that the right PPC was involved in the visual search at about SOA=150 ms after visual stimulus presentation. The magnetic stimulation to the right PPC disturbed the processing of the visual search. However, the magnetic stimulation to the left PPC gives no effect on the processing of the visual search.

Blindness and visual impairment in opera.

Science.gov (United States)

Aydin, Pinar; Ritch, Robert; O'Dwyer, John

2018-01-01

The performing arts mirror the human condition. This study sought to analyze the reasons for inclusion of visually impaired characters in opera, the cause of the blindness or near blindness, and the dramatic purpose of the blindness in the storyline. We reviewed operas from the 18 th century to 2010 and included all characters with ocular problems. We classified the cause of each character's ocular problem (organic, nonorganic, and other) in relation to the thematic setting of the opera: biblical and mythical, blind beggars or blind musicians, historical (real or fictional characters), and contemporary or futuristic. Cases of blindness in 55 characters (2 as a choir) from 38 operas were detected over 3 centuries of repertoire: 11 had trauma-related visual impairment, 5 had congenital blindness, 18 had visual impairment of unknown cause, 9 had psychogenic or malingering blindness, and 12 were symbolic or miracle-related. One opera featured an ophthalmologist curing a patient. The research illustrates that visual impairment was frequently used as an artistic device to enhance the intent and situate an opera in its time.

"The Barking Girl": A Case Report of Psychogenic Cough in a Child with a Review of Literature.

Science.gov (United States)

Jakati, Praveen Kumar; Naskar, Subrata; Khanna, Anisha

2017-01-01

A 9-year-old girl presented with 2-month history of continuous coughing; despite detailed evaluation, no organic cause was found. Considering the provisional diagnosis of a psychogenic cough, she was advised for psychiatry consultation. After a psychological assessment, she was found to have comorbid anxiety (Screen for Child Anxiety Related Disorders score- 25) along with punitive parenting and sibling rivalry issues. She was initially treated with parental psychoeducation, play therapy, and behavior therapy. Since she did not show expected progress with the treatment, low-dose escitalopram was started along with the ongoing therapy, considering her anxiety. There was a significant improvement in her symptoms in 1-month follow-up. She maintained improvement during further follow-ups. This case illustrates the need to identify and treat comorbid psychiatric issues in the management of a psychogenic cough.

Acupuncture therapy: mechanism of action, efficacy, and safety: a potential intervention for psychogenic disorders?

Science.gov (United States)

2014-01-01

Scientific bases for the mechanism of action of acupuncture in the treatment of pain and the pathogenic mechanism of acupuncture points are briefly summarized. The efficacy and safety of acupuncture therapy is discussed based on the results of German clinical trials. A conclusion on the role for acupuncture in the treatment of psychogenic disorders could not be reached. PMID:24444292

Attention in Parkinson’s Disease Mimicking Suggestion in Psychogenic Movement Disorder

Directory of Open Access Journals (Sweden)

Jong Sam Baik

2012-10-01

Full Text Available The various reported psychogenic movement disorders (PMDs include tremor, dystonia, myoclonus, gait disorder, Parkinsonism, tics, and chorea. Although it is not easy to diagnose PMDs, several features such as distractibility, entrainment, suggestion and placebo trial are quite helpful to diagnose. Especially, distractibility or suggestion is a good tool to do in outpatient clinic easily. We describe a patient with parkinsonian features which were improved by internal suggestion to focusing attention. Initially, we suspected her diagnosis as PMDs; however she was confirmed with organic Parkinson’s disease later.

A visual test based on a freeware software for quantifying and displaying night-vision disturbances: study in subjects after alcohol consumption.

Science.gov (United States)

Castro, José J; Ortiz, Carolina; Pozo, Antonio M; Anera, Rosario G; Soler, Margarita

2014-05-07

In this work, we propose the Halo test, a simple visual test based on a freeware software for quantifying and displaying night-vision disturbances perceived by subjects under different experimental conditions, more precisely studying the influence of the alcohol consumption on visual function. In the Halo test, viewed on a monitor, the subject's task consists of detecting luminous peripheral stimuli around a central high-luminance stimulus over a dark background. The test, performed by subjects before and after consuming alcoholic drinks, which deteriorate visual performance, evaluates the influence that alcohol consumption exerts on the visual-discrimination capacity under low illumination conditions. Measurements were made monocularly and binocularly. Pupil size was also measured in both conditions (pre/post). Additionally, we used a double-pass device to measure objectively the optical-quality of the eye and corroborate the results from the Halo test. We found a significant deterioration of the discrimination capacity after alcohol consumption, indicating that the higher the breath-alcohol content, the greater the deterioration of the visual-discrimination capacity. After alcohol intake, the graphical results showed a greater area of undetected peripheral stimuli around the central high-luminance stimulus. An enlargement of the pupil was also observed and the optical quality of the eye was deteriorated after alcohol consumption. A greater influence of halos and other night-vision disturbances were reported with the Halo test after alcohol consumption. The Halo freeware software constitutes a positive contribution for evaluating nighttime visual performance in clinical applications, such as reported here, but also in patients after refractive surgery (where halos are present) or for monitoring (time course) some ocular pathologies under pharmacological treatment.

“The Barking Girl”: A Case Report of Psychogenic Cough in a Child with a Review of Literature

Science.gov (United States)

Jakati, Praveen Kumar; Naskar, Subrata; Khanna, Anisha

2017-01-01

A 9-year-old girl presented with 2-month history of continuous coughing; despite detailed evaluation, no organic cause was found. Considering the provisional diagnosis of a psychogenic cough, she was advised for psychiatry consultation. After a psychological assessment, she was found to have comorbid anxiety (Screen for Child Anxiety Related Disorders score- 25) along with punitive parenting and sibling rivalry issues. She was initially treated with parental psychoeducation, play therapy, and behavior therapy. Since she did not show expected progress with the treatment, low-dose escitalopram was started along with the ongoing therapy, considering her anxiety. There was a significant improvement in her symptoms in 1-month follow-up. She maintained improvement during further follow-ups. This case illustrates the need to identify and treat comorbid psychiatric issues in the management of a psychogenic cough. PMID:28852260

Which patients with epilepsy are at risk for psychogenic nonepileptic seizures (PNES)? A multicenter case-control study

NARCIS (Netherlands)

Wissel, Benjamin D.; Dwivedi, Alok K.; Gaston, Tyler E.; Rodriguez-Porcel, Federico J.; Aljaafari, Danah; Hopp, Jennifer L.; Krumholz, Allan; van der Salm, Sandra M. A.; Andrade, Danielle M.; Borlot, Felippe; Moseley, Brian D.; Cavitt, Jennifer L.; Williams, Stevie; Stone, Jon; LaFrance, W. Curt; Szaflarski, Jerzy P.; Espay, Alberto J.

2016-01-01

We sought to examine the clinical and electrographic differences between patients with combined epileptic (ES) and psychogenic nonepileptic seizures (PNES) and age- and gender-matched patients with ES-only and PNES-only. Data from 138 patients (105 women [77%]), including 46 with PNES/ES

Emotional stimuli-provoked seizures potentially misdiagnosed as psychogenic non-epileptic attacks: A case of temporal lobe epilepsy with amygdala enlargement

Directory of Open Access Journals (Sweden)

Hidetaka Tamune

Full Text Available The association between emotional stimuli and temporal lobe epilepsy (TLE is largely unknown. Here, we report the case of a depressed, 50-year-old female complaining of episodes of a “spaced out” experience precipitated by emotional stimuli. Psychogenic non-epileptic attacks were suspected. However, video-EEG coupled with emotional stimuli-provoked procedures and MRI findings of amygdala enlargement, led to the diagnosis of left TLE. Accurate diagnosis and explanation improved her subjective depression and seizure frequency. This case demonstrated that emotional stimuli can provoke seizures in TLE and suggested the involvement of the enlarged amygdala and the modulation of emotion-related neural circuits. Keywords: Video-EEG, Psychogenic non-epileptic attacks, Temporal lobe epilepsy, Amygdala enlargement, Reflex seizure, Provoked seizure

Cerebral Activity Changes in Different Traditional Chinese Medicine Patterns of Psychogenic Erectile Dysfunction Patients

OpenAIRE

Liu, Qi; Zhang, Peihai; Pan, Junjie; Li, Zhengjie; Liu, Jixin; Li, Guangsen; Qin, Wei; You, Yaodong; Yu, Xujun; Sun, Jinbo; Dong, Minghao; Gong, Qiyong; Guo, Jun; Chang, Degui

2015-01-01

Background. Pattern differentiation is the foundation of traditional Chinese medicine (TCM) treatment for erectile dysfunction (ED). This study aims to investigate the differences in cerebral activity in ED patients with different TCM patterns. Methods. 27 psychogenic ED patients and 27 healthy subjects (HS) were enrolled in this study. Each participant underwent an fMRI scan in resting state. The fractional amplitude of low-frequency fluctuation (fALFF) was used to detect the brain activity ...

Advantageous Use of Hypnosis in a Case of Psychogenic Vomiting.

Science.gov (United States)

Chandrashekhar, Roopa

2016-04-01

This case study describes in detail the role of hypnosis in treatment of a case of psychogenic vomiting. The patient, a 60-yearold woman, had been suffering for 9 months from episodes of vomiting which resulted in weight loss, dehydration, and hypokalemia. She was a conscientious woman with high standards of behavior, which did not allow an expression of the extreme hostility she felt toward her daughter-in-law. Hypnotherapeutic sessions reduced her anxiety, restored her sleep, improved mood, and helped deepen rapport, all of which created the ideal setting for Gestalt's empty chair technique. Integrating hypnosis greatly enhanced the quality of the empty chair dialogue, which by bringing about a shift in the patient's emotions from hostility to sympathy, facilitated recovery.

Ethical dilemmas in pediatric and adolescent psychogenic nonepileptic seizures.

Science.gov (United States)

Cole, Cristie M; Falcone, Tatiana; Caplan, Rochelle; Timmons-Mitchell, Jane; Jares, Kristine; Ford, Paul J

2014-08-01

To date, only a very narrow window of ethical dilemmas in psychogenic nonepileptic seizures (PNES) has been explored. Numerous distinct ethical dilemmas arise in diagnosing and treating pediatric and adolescent patients with PNESs. Important ethical values at stake include trust, transparency, confidentiality, professionalism, autonomy of all stakeholders, and justice. In order to further elucidate the ethical challenges in caring for this population, an ethical analysis of the special challenges faced in four specific domains is undertaken: (1) conducting and communicating a diagnosis of PNESs, (2) advising patients about full transparency and disclosure to community including patients' peers, (3) responding to requests to continue antiepileptic drugs, and (4) managing challenges arising from school policy and procedure. An analysis of these ethical issues is essential for the advancement of best care practices that promote the overall well-being of patients and their families. Copyright © 2014 Elsevier Inc. All rights reserved.

Transient epileptic amnesia differentiated from psychogenic "fugue": neuropsychological, EEG, and PET findings.

Science.gov (United States)

Kopelman, M D; Panayiotopoulos, C P; Lewis, P

1994-08-01

A patient had repeated episodes of transient loss of memory, which had been attributed to psychogenic causes. Preservation of his sense of personal identity and the presence of repetitive questioning indicated an organic basis, however, and the multiplicity of the attacks and their brief duration suggested an epileptic aetiology. Although three standard EEGs, CT and MRI were all normal, two sleep EEGs confirmed bilateral foci in the temporal lobes. The attacks responded to an anticonvulsant. A fluoro-deoxyglucose PET scan, performed a few months after the most recent attack, was normal. The patient also had impaired anterograde memory that persisted six months after recovery from the acute attacks.

A systematic review of suggestive seizure induction for the diagnosis of psychogenic nonepileptic seizures.

Science.gov (United States)

Popkirov, Stoyan; Grönheit, Wenke; Wellmer, Jörg

2015-09-01

Suggestive seizure induction is a widely used method for diagnosing psychogenic nonepileptic seizures (PNES). Despite seven decades of multidisciplinary research, however, there is still no unified protocol, no definitive agreement on the ethical framework and no consensus on diagnostic utility. This systematic review surveys the evidence at hand and addresses clinically relevant aspects of suggestive seizure induction. In addition to its use for facilitating the diagnostic process, its mechanism of action and utility in elucidating the psychopathology of PNES will be discussed. Copyright © 2015 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

Confirming psychogenic nonepileptic seizures with video-EEG: sex matters.

Science.gov (United States)

Noe, Katherine H; Grade, Madeline; Stonnington, Cynthia M; Driver-Dunckley, Erika; Locke, Dona E C

2012-03-01

The influence of gender on psychogenic nonepileptic seizures (PNES) diagnosis was examined retrospectively in 439 subjects undergoing video-EEG (vEEG) for spell classification, of whom 142 women and 42 men had confirmed PNES. The epileptologist's predicted diagnosis was correct in 72% overall. Confirmed epilepsy was correctly predicted in 94% men and 88% women. In contrast, confirmed PNES was accurately predicted in 86% women versus 61% men (p=0.003). Sex-based differences in likelihood of an indeterminate admission were not observed for predicted epilepsy or physiologic events, but were for predicted PNES (39% men, 12% women, p=0.0002). More frequent failure to record spells in men than women with predicted PNES was not explained by spell frequency, duration of monitoring, age, medication use, or personality profile. PNES are not only less common in men, but also more challenging to recognize in the clinic, and even when suspected more difficult to confirm with vEEG. Copyright © 2012 Elsevier Inc. All rights reserved.

Astasia-Abasia and Ganser syndrome in a preadolescent girl: A case report

Directory of Open Access Journals (Sweden)

Stanković Miodrag

2015-01-01

Full Text Available Introduction. Astasia is the inability to maintain an upright body position without assistance in the absence of motor weakness or sensory loss. Abasia is described as the inability to walk or as uncoordinated walking, while preserving mobility of the lower limbs. Ganser syndrome is described as a dissociative disorder characterized by approximate answers, somatic conversion symptoms, clouding of consciousness, as well as visual and auditory pseudohallucinations. The aim of this study is to present a case that seemed like a combination of neurological and internal disturbances, but actually represented a psychogenic disorder. Case Outline. This paper presents the case of a 13-year-old patient with the first manifestation of the inability to walk and stand. Medical history, diagnostic instruments and differential diagnostic methods have been presented in detail. The clinical manifestation was initially interpreted as a neurological disorder. However, after the application of diagnostic procedures and a change in family circumstances, the patient was diagnosed with a psychogenic movement disorder, astasia-abasia, with progressive clinical presentation that included dissociative psychotic reactions (Ganser syndrome. Differential diagnosis as well as the elements of the therapeutic approach have been discussed. Conclusion. Presenting a case of psychogenic astasia-abasia in children contributes to a better understanding and differentiating between conditions with a clinical presentation of signs and symptoms dealt with by other branches of medicine.

Conversion disorder as psychogenic nonepileptic seizures in suspected cancer: a case report.

Science.gov (United States)

Jimenez, Xavier F; Sharma, Jennifer S; Dar, Syma A

2014-01-01

Psychogenic nonepileptic seizures (PNES), a form of conversion disorder, are paroxysmal episodes resembling epilepsy while lacking electrographic correlation. The phenomenon has rarely been reported in elderly patients and has not been associated with a new-onset medical diagnosis. We present the case of an 81-year-old female with no past psychiatric or traumatic history who developed PNES within the context of a new, suspected cancer. To our knowledge, this is the first such reported case of a suspected cancer (or otherwise medical) diagnosis contributing directly and temporally to the development of PNES. Discussion of involved psychosocial variables follows the vignette, and a brief review of relevant literature is offered. Copyright © 2014 Elsevier Inc. All rights reserved.

Are psychogenic non-epileptic seizures just another symptom of conversion disorder?

Science.gov (United States)

Kanaan, Richard A A; Duncan, Roderick; Goldstein, Laura H; Jankovic, Joseph; Cavanna, Andrea E

2017-05-01

Psychogenic non-epileptic seizures (PNES) are classified with other functional neurological symptoms as 'Conversion Disorder', but there are reasons to wonder whether this symptomatology constitutes a distinct entity. We reviewed the literature comparing PNES with other functional neurological symptoms. We find eight studies that directly examined this question. Though all but one found significant differences-notably in presenting age, trauma history, and dissociation-they were divided on whether these differences represented an important distinction. We argue that the aetiological and mechanistic distinctions they support, particularly when bolstered by additional data, give reason to sustain a separation between these conditions. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

A positive diagnosis of functional (psychogenic) tics.

Science.gov (United States)

Demartini, B; Ricciardi, L; Parees, I; Ganos, C; Bhatia, K P; Edwards, M J

2015-03-01

Functional tics, also called psychogenic tics or pseudo-tics, are difficult to diagnose because of the lack of diagnostic criteria and their clinical similarities to organic tics. The aim of the present study was to report a case series of patients with documented functional tics and to describe their clinical characteristics, risk factors and psychiatric comorbidity. Also clinical tips are suggested which might help the differential diagnosis in clinical practice. Eleven patients (mean age at onset 37.2, SD 13.5; three females) were included with a documented or clinically established diagnosis of functional tics, according to consultant neurologists who have specific expertise in functional movement disorders or in tic disorders. Adult onset, absent family history of tics, inability to suppress the movements, lack of premonitory sensations, absence of pali-, echo- and copro-phenomena, presence of blocking tics, the lack of the typical rostrocaudal tic distribution and the coexistence of other functional movement disorders were common in our patients. Our data suggest that functional tics can be differentiated from organic tics on clinical grounds, although it is also accepted that this distinction can be difficult in certain cases. Clinical clues from history and examination described here might help to identify patients with functional tics. © 2014 EAN.

Visual stimulation facilitates penile responses to vibration in men with and without erectile disorder

NARCIS (Netherlands)

Janssen, E.; Everaerd, W.; van Lunsen, R. H.; Oerlemans, S.

1994-01-01

This study compared reflexogenic and psychogenic penile responses in men with and without erectile disorder. It was hypothesized that men with psychogenic erectile dysfunction respond minimally to vibrotactile stimulation. An enhancement of penile responses was expected when vibration was combined

[Psychogenic tics: clinical characteristics and prevalence].

Science.gov (United States)

Janik, Piotr; Milanowski, Lukasz; Szejko, Natalia

2014-01-01

Clinical characteristics and the prevalence of psychogenic tics (PT) METHODS: 268 consecutively examined patients aged 4 to 54 years (221 men, 47 females; 134 children, 134 adults) with tic phenotype: Gilles de la Tourette syndrome (GTS, n = 255), chronic motor tics (n = 6), chronic vocal tics (n= 1), transient tics (n = 1), tics unclassified (n = 2), PT (n= 5) were analyzed. The diagnosis of tic disorders was made on the DSM-IV-TR criteria and mental disorders by psychiatrists. PT were found in 5 patients (1.9%), aged 17 to 51 years, four men and one woman. The phenotype included vocalizations and complex movements. In none of the patients simple motor facial tics, inability to tic suppress, unchanging clinical pattern, peak severity from the beginning of the disease, lack of concern about the disease were present. The absence of premonitory urges, regression in unexpected positions, and the presence of atypical for GTS mental disorders were found in two persons. PT occurred in three persons in whom organic tics were present in childhood. Pharmacological treatment and psychotherapy were unsuccessful. In two persons spontaneous resolution occurred, in two patients the tics persist, in one person the course of PT is unknown. PT are rare and may occur in patients with organic tics. The most typical features of PT are: early onset in adulthood, lack of simple motor tics, inability to tic suppress. The diagnosis is established if a few atypical symptoms for organic tics occur.

Developing Tests of Visual Dependency

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Kindrat, Alexandra N.

2011-01-01

Astronauts develop neural adaptive responses to microgravity during space flight. Consequently these adaptive responses cause maladaptive disturbances in balance and gait function when astronauts return to Earth and are re-exposed to gravity. Current research in the Neuroscience Laboratories at NASA-JSC is focused on understanding how exposure to space flight produces post-flight disturbances in balance and gait control and developing training programs designed to facilitate the rapid recovery of functional mobility after space flight. In concert with these disturbances, astronauts also often report an increase in their visual dependency during space flight. To better understand this phenomenon, studies were conducted with specially designed training programs focusing on visual dependency with the aim to understand and enhance subjects ability to rapidly adapt to novel sensory situations. The Rod and Frame test (RFT) was used first to assess an individual s visual dependency, using a variety of testing techniques. Once assessed, subjects were asked to perform two novel tasks under transformation (both the Pegboard and Cube Construction tasks). Results indicate that head position cues and initial visual test conditions had no effect on an individual s visual dependency scores. Subjects were also able to adapt to the manual tasks after several trials. Individual visual dependency correlated with ability to adapt manual to a novel visual distortion only for the cube task. Subjects with higher visual dependency showed decreased ability to adapt to this task. Ultimately, it was revealed that the RFT may serve as an effective prediction tool to produce individualized adaptability training prescriptions that target the specific sensory profile of each crewmember.

Identifying seizure clusters in patients with psychogenic nonepileptic seizures.

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Baird, Grayson L; Harlow, Lisa L; Machan, Jason T; Thomas, Dave; LaFrance, W C

2017-08-01

The present study explored how seizure clusters may be defined for those with psychogenic nonepileptic seizures (PNES), a topic for which there is a paucity of literature. The sample was drawn from a multisite randomized clinical trial for PNES; seizure data are from participants' seizure diaries. Three possible cluster definitions were examined: 1) common clinical definition, where ≥3 seizures in a day is considered a cluster, along with two novel statistical definitions, where ≥3 seizures in a day are considered a cluster if the observed number of seizures statistically exceeds what would be expected relative to a patient's: 1) average seizure rate prior to the trial, 2) observed seizure rate for the previous seven days. Prevalence of clusters was 62-68% depending on cluster definition used, and occurrence rate of clusters was 6-19% depending on cluster definition. Based on these data, clusters seem to be common in patients with PNES, and more research is needed to identify if clusters are related to triggers and outcomes. Copyright © 2017 Elsevier Inc. All rights reserved.

A comparison of personality disorder characteristics of patients with nonepileptic psychogenic pseudoseizures with those of patients with epilepsy.

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Harden, Cynthia L; Jovine, Luydmilla; Burgut, Fadime T; Carey, Bridget T; Nikolov, Blagovest G; Ferrando, Stephen J

2009-03-01

We sought to determine the type of personality disorder cluster associated with patients with nonepileptic psychogenic seizures (NES) compared with that of patients with epileptic seizures (ES). Consecutive adult patients admitted for video/EEG monitoring found to have NES were compared with a simultaneously admitted patient with confirmed epilepsy. Personality was assessed using the Structured Clinical Interview for DSM-IV-TR Axis II Personality Disorders. Personality disorders were then divided into personality clusters described in the DSM-IV-TR: A = paranoid, schizotypal, schizoid; B = borderline, histrionic, antisocial, narcissistic; or C = avoidant, dependent, obsessive-compulsive. Thirteen of 16 patients with NES and 12 of 16 patients with ES met criteria for personality disorders. Patients with NES were more likely to meet criteria for a personality disorder in Cluster A or B, compared with patients with ES, who were more likely to have Cluster C personality disorders (chi(2) test, P=0.007). We propose that the personality traits of patients with NES contribute to the development of nonepileptic psychogenic seizures. However, the large proportion of patients with ES with Cluster C personality disorders was unexpected, and further, for the patients with epilepsy, the direction of the association of their personality traits with the development of epilepsy is unknown.

Time Trends in Murray's Psychogenic Needs over Three Decades in Swedish 75-Year-Olds.

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Billstedt, Eva; Waern, Margda; Falk, Hanna; Duberstein, Paul; Östling, Svante; Hällström, Tore; Skoog, Ingmar

2017-01-01

While time trends in personality traits have been suggested in younger cohorts, little is known regarding this issue in older adults. To test for birth cohort changes in psychogenic needs according to Murray's theory of personality in two birth cohorts of 75-year-olds born 1901-1902 and 1930. Two population-based birth cohorts were examined at the age of 75 years in 1976-1977 and in 2005-2006. Psychogenic needs according to Murray were measured with the Cesarec-Marke Personality Schedule (CMPS), a Swedish version of the Edwards Personal Preference Schedule. Scores on the CMPS subscales (achievement, affiliation, aggression, defence of status, guilt feelings, dominance, exhibition, autonomy, nurturance, order, succorance, and acquiescence) were compared between cohorts. Achievement, exhibition, dominance, aggression, affiliation, and succorance scores were higher, and order and acquiescence scores lower, in the more recent birth cohort of 75-year-olds. Women scored lower than men on exhibition and dominance, and higher on defence of status, guilt feelings, affiliation, nurturance, and succorance. Interaction effects between cohort and sex were found for achievement (women scored lower than men in 1976-1977 but not in 2005-2006), order (the lower scores in 2005-2006 were more accentuated among men), and acquiescence (increased in men and decreased in women). The later-born birth cohort scored higher on self-centred traits, such as more dominant, competitive, and exhibitive traits as well as the need to be taken care of and have friends around, but it scored lower on the need for order. The gap between men and women regarding achievement decreased, possibly reflecting women's more prominent role in society. © 2016 S. Karger AG, Basel.

Psychogenic nonepileptic seizures in patients with surgically treated temporal lobe epilepsy: Presurgical and de novo postsurgical occurrence.

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González Otárula, Karina A; Tan, Yee-Leng; Dubeau, François; Correa, José A; Chang, Edward; Hall, Jeffery A; Knowlton, Robert C; Kobayashi, Eliane

2017-10-01

Whether occurring before or after an epilepsy surgery, psychogenic nonepileptic seizures (PNES) impact treatment options and quality of life of patients with epilepsy. We investigated the frequency of pre- and postsurgical PNES, and the postsurgical Engel and psychiatric outcomes in patients with drug-resistant temporal lobe epilepsy (TLE). We reviewed 278 patients with mean age at surgery of 37.1±12.4years. Postsurgical follow-up information was available in 220 patients, with average follow-up of 4years. Nine patients (9/278 or 3.2%) had presurgical documented PNES. Eight patients (8/220 or 3.6%) developed de novo PNES after surgery. Pre- and postsurgery psychiatric comorbidities were similar to the patients without PNES. After surgery, in the group with presurgical PNES, five patients were seizure-free, and three presented persistent PNES. In the group with de novo postsurgery PNES, 62.5% had Engel II-IV, and 37.5% had Engel I. All presented PNES at last follow-up. Presurgical video-EEG monitoring is crucial in the diagnosis of coexisting PNES. Patients presenting presurgical PNES and drug-resistant TLE should not be denied surgery based on this comorbidity, as they can have good postsurgical epilepsy and psychiatric outcomes. Psychogenic nonepileptic seizures may appear after TLE surgery in a low but noteworthy proportion of patients regardless of the Engel outcome. Copyright © 2017 Elsevier Inc. All rights reserved.

Attractive Flicker--Guiding Attention in Dynamic Narrative Visualizations.

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Waldner, Manuela; Le Muzic, Mathieu; Bernhard, Matthias; Purgathofer, Werner; Viola, Ivan

2014-12-01

Focus+context techniques provide visual guidance in visualizations by giving strong visual prominence to elements of interest while the context is suppressed. However, finding a visual feature to enhance for the focus to pop out from its context in a large dynamic scene, while leading to minimal visual deformation and subjective disturbance, is challenging. This paper proposes Attractive Flicker, a novel technique for visual guidance in dynamic narrative visualizations. We first show that flicker is a strong visual attractor in the entire visual field, without distorting, suppressing, or adding any scene elements. The novel aspect of our Attractive Flicker technique is that it consists of two signal stages: The first "orientation stage" is a short but intensive flicker stimulus to attract the attention to elements of interest. Subsequently, the intensive flicker is reduced to a minimally disturbing luminance oscillation ("engagement stage") as visual support to keep track of the focus elements. To find a good trade-off between attraction effectiveness and subjective annoyance caused by flicker, we conducted two perceptual studies to find suitable signal parameters. We showcase Attractive Flicker with the parameters obtained from the perceptual statistics in a study of molecular interactions. With Attractive Flicker, users were able to easily follow the narrative of the visualization on a large display, while the flickering of focus elements was not disturbing when observing the context.

Map showing areas of visible land disturbances caused by two military training operations in the Mojave Desert, California

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Prose, D.V.

1986-01-01

This map shows areas that retain visible land disturbances produced during two military armored-vehicle training operations in the Mojave Desert, California. The map documents the lasting visual effects these operations have on this arid region and provides a data base for monitoring changes in the extent of visual disturbances in the future.

Psychogenic and neural visual-cue response in PD dopamine dysregulation syndrome.

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Loane, Clare; Wu, Kit; O'Sullivan, Sean S; Lawrence, Andrew D; Woodhead, Zoe; Lees, Andrew J; Piccini, Paola; Politis, Marios

2015-11-01

Dopamine dysregulation syndrome (DDS) in Parkinson's disease (PD) patients refers to the compulsive use of dopaminergic replacement therapy and has serious psycho-social consequences. Mechanisms underlying DDS are not clear although has been linked to dysfunctional brain reward networks. With fMRI, we investigate behavioral and neural response to drug-cues in six PD DDS patients and 12 PD control patients in both the ON and OFF medication state. Behavioral measures of liking, wanting and subjectively 'feeling ON medication' were also collected. Behaviorally, PD DDS patients feel less ON and want their drugs more at baseline compared to PD controls. Following drug-cue exposure, PD DDS patients feel significantly more ON medication, which correlates with significant increases in reward related regions. The results demonstrate that exposure to drug-cues increases the subjective feeling of being 'ON' medication which corresponds to dysfunctional activation in reward related regions in PD DDS patients. These findings should be extended in future studies. Visual stimuli being sufficient to elicit behavioral response through neuroadaptations could have direct implications to the management of addictive behavior. Copyright © 2015 Elsevier Ltd. All rights reserved.

Psychogenic seizures and frontal disconnection: EEG synchronisation study.

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Knyazeva, Maria G; Jalili, Mahdi; Frackowiak, Richard S; Rossetti, Andrea O

2011-05-01

Psychogenic non-epileptic seizures (PNES) are paroxysmal events that, in contrast to epileptic seizures, are related to psychological causes without the presence of epileptiform EEG changes. Recent models suggest a multifactorial basis for PNES. A potentially paramount, but currently poorly understood factor is the interplay between psychiatric features and a specific vulnerability of the brain leading to a clinical picture that resembles epilepsy. Hypothesising that functional cerebral network abnormalities may predispose to the clinical phenotype, the authors undertook a characterisation of the functional connectivity in PNES patients. The authors analysed the whole-head surface topography of multivariate phase synchronisation (MPS) in interictal high-density EEG of 13 PNES patients as compared with 13 age- and sex-matched controls. MPS mapping reduces the wealth of dynamic data obtained from high-density EEG to easily readable synchronisation maps, which provide an unbiased overview of any changes in functional connectivity associated with distributed cortical abnormalities. The authors computed MPS maps for both Laplacian and common-average-reference EEGs. In a between-group comparison, only patchy, non-uniform changes in MPS survived conservative statistical testing. However, against the background of these unimpressive group results, the authors found widespread inverse correlations between individual PNES frequency and MPS within the prefrontal and parietal cortices. PNES appears to be associated with decreased prefrontal and parietal synchronisation, possibly reflecting dysfunction of networks within these regions.

Antidepressant treatment outcomes of psychogenic movement disorder.

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Voon, Valerie; Lang, Anthony E

2005-12-01

Psychogenic movement disorder (PMD) is a subtype of conversion disorder. We describe the outcomes of a series of PMD patients following antidepressant treatment. Twenty-three outpatients with chronic PMD, diagnosed using Fahn and Williams' criteria, underwent psychiatric assessment. The patients were referred for assessment and management from January 2003 to July 2004. Fifteen agreed to be treated with antidepressants. Patients received citalopram or paroxetine; those who did not respond after 4 weeks of taking an optimal dose were switched to venlafaxine. Concurrently, 3 had supportive psychotherapy, and 1 had family intervention. Assessments included the DSM-IV-based Mini-International Neuropsychiatric Interview and scales measuring depression, anxiety, and motor and global severity. Eighteen patients (78%) had at least 1 Axis I diagnosis in addition to the somatoform diagnosis, and 3 (13%) had somatization disorder. Five (22%) had previous psychiatric contact. Nine (39%) had previously been treated with antidepressants, but only 4 (17%) had adequate trials. No significant differences existed in patient characteristics between treated and untreated groups. Among treated patients, Montgomery-Asberg Depression Rating Scale scores improved from baseline (p hypochondriasis, somatization disorder, or probable factitious disorder/malingering, of whom none improved. All of the patients with primary conversion disorder had a current or previous depressive or anxiety disorder compared with 40% (N = 2) of the patients with additional somatoform diagnoses. Our preliminary findings suggest that chronic PMD with primary conversion symptoms and with recent or current depression or anxiety may respond to antidepressants. Further well-designed studies, now under way, are required to confirm these findings.

Postural Orthostatic Tachycardia With Chronic Fatigue After HPV Vaccination as Part of the “Autoimmune/Auto-inflammatory Syndrome Induced by Adjuvants”

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Lucija Tomljenovic PhD

2014-03-01

Full Text Available We report the case of a 14-year-old girl who developed postural orthostatic tachycardia syndrome (POTS with chronic fatigue 2 months following Gardasil vaccination. The patient suffered from persistent headaches, dizziness, recurrent syncope, poor motor coordination, weakness, fatigue, myalgias, numbness, tachycardia, dyspnea, visual disturbances, phonophobia, cognitive impairment, insomnia, gastrointestinal disturbances, and a weight loss of 20 pounds. The psychiatric evaluation ruled out the possibility that her symptoms were psychogenic or related to anxiety disorders. Furthermore, the patient tested positive for ANA (1:1280, lupus anticoagulant, and antiphospholipid. On clinical examination she presented livedo reticularis and was diagnosed with Raynaud’s syndrome. This case fulfills the criteria for the autoimmune/auto-inflammatory syndrome induced by adjuvants (ASIA. Because human papillomavirus vaccination is universally recommended to teenagers and because POTS frequently results in long-term disabilities (as was the case in our patient, a thorough follow-up of patients who present with relevant complaints after vaccination is strongly recommended.

Neuropsychiatric Disturbances and Hypopituitarism After Traumatic Brain Injury in an Elderly Man

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Yi-Cheng Chang

2006-01-01

Full Text Available Neuropsychiatric or cognitive disturbances are common complications after traumatic brain injury. They are commonly regarded as irreversible sequelae of organic brain injuries. We report a case of hypopituitarism in a 77-year-old man who presented with long-term neuropsychiatric disturbances, including cognitive impairment, disturbed sleep patterns, personality change, loss of affect, and visual and auditory hallucinations after a traumatic subdural hemorrhage. The treatment response to hormone replacement therapy was nearly complete. Hypopituitarism is rarely considered in patients who sustain traumatic brain injury and the neuropsychiatric manifestations of posttraumatic hypopituitarism have rarely been reported. This case highlights the importance of hypopituitarism as a potential reversible cause of neuropsychiatric disturbances after traumatic brain injury.

Rating scale for psychogenic nonepileptic seizures: scale development and clinimetric testing.

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Cianci, Vittoria; Ferlazzo, Edoardo; Condino, Francesca; Mauvais, Hélène Somma; Farnarier, Guy; Labate, Angelo; Latella, Maria Adele; Gasparini, Sara; Branca, Damiano; Pucci, Franco; Vazzana, Francesco; Gambardella, Antonio; Aguglia, Umberto

2011-06-01

Our aim was to develop a clinimetric scale evaluating motor phenomena, associated features, and severity of psychogenic nonepileptic seizures (PNES). Sixty video/EEG-recorded PNES induced by suggestion maneuvers were evaluated. We examined the relationship between results from this scale and results from the Clinical Global Impression (CGI) scale to validate this technique. Interrater reliabilities of the PNES scale for three raters were analyzed using the AC1 statistic, Kendall's coefficient of concordance (KCC), and intraclass correlation coefficients (ICCs). The relationship between the CGI and PNES scales was evaluated with Spearman correlations. The AC1 statistic demonstrated good interrater reliability for each phenomenon analyzed (tremor/oscillation, tonic; clonic/jerking, hypermotor/agitation, atonic/akinetic, automatisms, associated features). KCC and the ICC showed moderate interrater agreement for phenomenology, associated phenomena, and total PNES scores. Spearman's correlation of mean CGI score with mean total PNES score was 0.69 (Pscale described here accurately evaluates the phenomenology of PNES and could be used to assess and compare subgroups of patients with PNES. Copyright © 2011 Elsevier Inc. All rights reserved.

Disturbance of visual functions as a result of temporary blinding from low power lasers

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Reidenbach, Hans-Dieter

2010-04-01

exposure durations texp from 0.25 s up to 10 s was found. The inability to read due to the disturbance produced by afterimages lasts for about 20 s even if the exposure is not more than 0.25 s from a laser with about 0.8 mW optical output power. In addition to the physiological effects of temporary blinding the psychological glare was determined as a function of the angle between line of sight and beam direction. It was found that already at output powers below 30 μW of a He-Nelaser the subjects reported intense glare effects and felt uncomfortable due to the high brightness. Instead of the standard visual acuity measurement used by eye care professionals, a reading test on a computer monitor was applied after laser irradiation. In this case two different lasers were used as a dazzling light source, one with a wavelength of 632.8 nm and the other with 532 nm. The maximum applied optical power in a 7-mm aperture, which is equivalent to the pupil diameter of a dark adapted eye, was 0.783 mW. The exposure durations were chosen as 0.25 s, 0.5 s, 1 s, 5 s, and 20 s.

Refractive Lens Exchange with Multifocal Intraocular Lens for Treatment of Chronic Intermittent Spasm of the Near Reflex

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Guy Sallet

2017-12-01

Full Text Available We report the case of an emmetropic 32-year-old female with decreased uncorrected visual acuity and diplopia due to intermittent episodes of spasm of the near reflex. Neurologic, general, and ophthalmic examination could not find an organic cause. Attempts at spontaneous recovery, psychogenic therapy, and cycloplegic therapy were unsuccessful and the symptoms persisted for almost 5 years, leading to psychogenic distress. Final treatment with refractive lens exchange and implantation of a toric trifocal intraocular lens resolved the spasm of the near reflex, resulting in an uncorrected distance and near visual acuity of 20/20.

Severe psychogenic tremor of both wrists in a 13-year-old girl treated successfully with a customized wrist brace: a case report

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Schafflhuber Caroline

2011-04-01

Full Text Available Abstract Introduction Psychogenic movement disorders in childhood have been little researched. As there are few courses of treatment which have been evaluated, further examination and case studies about the treatment and clinical course of this rare occurrence of severe psychogenic tremor in childhood and adolescence are much needed. Case presentation A 13-year-old Caucasian girl with tremor in both wrists, severe enough to prevent her from attending school, was sent to our hospital. After a complete neurological and psychiatric examination, in-patient child-psychotherapeutic treatment was started, with careful consideration given to both chronic and acute stress factors which constitute her performance and exam anxiety in school as well as the girl's parents' conflicted relationship. With the aid of a customized wrist brace our patient was able to go to school and write despite the presence of a marked tremor, which in turn reduced her avoidance behavior and exam anxiety. By the end of her in-patient treatment, the tremor was still noticeable, but markedly reduced in severity (reduction 80%. Two weeks after she was discharged from hospital, the tremor had completely disappeared. Conclusion After careful clinical diagnostics, this kind of dissociative disorder should be treated appropriately with age-adapted cognitive-behavioral therapy to achieve positive and lasting benefits.

Neuropsychological analysis of a typewriting disturbance following cerebral damage.

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Boyle, M; Canter, G J

1987-01-01

Following a left CVA, a skilled professional typist sustained a disturbance of typing disproportionate to her handwriting disturbance. Typing errors were predominantly of the sequencing type, with spatial errors much less frequent, suggesting that the impairment was based on a relatively early (premotor) stage of processing. Depriving the subject of visual feedback during handwriting greatly increased her error rate. Similarly, interfering with auditory feedback during speech substantially reduced her self-correction of speech errors. These findings suggested that impaired ability to utilize somesthetic information--probably caused by the subject's parietal lobe lesion--may have been the basis of the typing disorder.

Cognitive-analytical therapy for a patient with functional neurological symptom disorder-conversion disorder (psychogenic myopia: A case study

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Hamid Nasiri

2015-01-01

Full Text Available Functional neurological symptom disorder commonly presents with symptoms and defects of sensory and motor functions. Therefore, it is often mistaken for a medical condition. It is well known that functional neurological symptom disorder more often caused by psychological factors. There are three main approaches namely analytical, cognitive and biological to manage conversion disorder. Any of such approaches can be applied through short-term treatment programs. In this case, study a 12-year-old boy with the diagnosed functional neurological symptom disorder (psychogenic myopia was put under a cognitive-analytical treatment. The outcome of this treatment modality was proved successful.

Cognitive-analytical therapy for a patient with functional neurological symptom disorder-conversion disorder (psychogenic myopia): A case study.

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Nasiri, Hamid; Ebrahimi, Amrollah; Zahed, Arash; Arab, Mostafa; Samouei, Rahele

2015-05-01

Functional neurological symptom disorder commonly presents with symptoms and defects of sensory and motor functions. Therefore, it is often mistaken for a medical condition. It is well known that functional neurological symptom disorder more often caused by psychological factors. There are three main approaches namely analytical, cognitive and biological to manage conversion disorder. Any of such approaches can be applied through short-term treatment programs. In this case, study a 12-year-old boy with the diagnosed functional neurological symptom disorder (psychogenic myopia) was put under a cognitive-analytical treatment. The outcome of this treatment modality was proved successful.

Software applications to three-dimensional visualization of forest landscapes -- A case study demontrating the use of visual nature studio (VNS) in visualizing fire spread in forest landscapes

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Brian J. Williams; Bo Song; Chou Chiao-Ying; Thomas M. Williams; John Hom

2010-01-01

Three-dimensional (3D) visualization is a useful tool that depicts virtual forest landscapes on computer. Previous studies in visualization have required high end computer hardware and specialized technical skills. A virtual forest landscape can be used to show different effects of disturbances and management scenarios on a computer, which allows observation of forest...

Management of visual disturbances in albinism: a case report

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Omar Rokiah

2012-09-01

Full Text Available Abstract Introduction A number of vision defects have been reported in association with albinism, such as photophobia, nystagmus and astigmatism. In many cases only prescription sunglasses are prescribed. In this report, the effectiveness of low-vision rehabilitation in albinism, which included prescription of multiple visual aids, is discussed. Case presentation We present the case of a 21-year-old Asian woman with albinism and associated vision defects. Her problems were blurring of distant vision, glare and her dissatisfaction with her current auto-focus spectacle-mounted telescope device, which she reported as being heavy as well as cosmetically unacceptable. We describe how low-vision rehabilitation using multiple visual aids, namely spectacles, special iris-tinted contact lenses with clear pupils, and bi-level telemicroscopic apparatus devices improved her quality of life. Subsequent to rehabilitation our patient is happier and continues to use the visual aids. Conclusions Contact lenses with a special iris tint and clear pupil area are useful aids to reduce the glare experienced by albinos. Bi-level telemicroscopic apparatus telemicroscopes fitted onto our patient’s prescription spectacles were cosmetically acceptable and able to improve her distance vision. As a result these low-vision rehabilitation approaches improved the quality of life of our albino patient.

Treatment decision for occipital arteriovenous malformations (AVMs) to achieve hemorrhagic control while maximizing visual preservation: Our experience and review of literature.

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Yang, Wuyang; Porras, Jose L; Philadelphia, Eunice; Law, Jody; Garzon-Muvdi, Tomas; Caplan, Justin M; Colby, Geoffrey P; Coon, Alexander L; Tamargo, Rafael J; Huang, Judy

2018-02-01

Despite concern of hemorrhagic risk, patients with occipital AVMs are at significant risk for visual disturbances after treatment. We aim to characterize the hemorrhage risk and visual disturbance in occipital AVMs patients from our experience and literature review. We performed retrospective review of occipital AVM patients seen at our institution from 1990 to 2015. Patient characteristics were compared using multivariable logistic regression with follow-up visual disturbance as the outcome. We also systematically reviewed the PubMed database for English literature describing occipital AVMs (with exclusion of case reports). Ninety-seven patients satisfied inclusion criteria for our study. Mean age was 34.9 ± 16.4 years, with 50.5% male. Thirty-one (32.0%) presented with hemorrhage, and 32 (33.0%) presented with visual disturbance. Average AVM size was 4.0 ± 2.5 cm. Twenty-five (25.8%) were conservatively managed, 13 (13.4%) underwent surgery, and the rest were managed by radiosurgery (52.6%) or embolization (8.2%), with an obliteration rate of 38.9% in treated patients. During average follow-up of 5.4 years, 6 patients (6.7%) hemorrhaged yielding an annual hemorrhage rate of 1.2% for all patients, and 0.0% for surgically-treated patients. Thirty-seven (38.3%) patients experienced visual disturbance in some capacity, nineteen (21.1%) had de novo visual disturbance, fourteen of which were surgically treated patients (19.4%). Multivariable analysis reveals visual disturbance at presentation (p = .012) and microsurgery (p = .047) are significantly predictors of follow-up visual disturbance. While hemorrhage control remains the primary goal of AVM treatment, visual preservation in occipital AVMs is also a major concern. Recommending patients for microsurgery should be weighed carefully and individualized as it bears the highest risk of visual field disturbance despite most optimal hemorrhage control. Copyright © 2017 Elsevier Ltd. All rights

The impact of psychological testing on the patients suffering from stomatopyrosis.

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Pokupec, Josipa Sanja Gruden; Gruden, Zdenka; Gruden, Vladimir

2011-12-01

Stomatopyrosis is commonly associated with stressful situations, which implies the importance of psychological conditions of the patients with this symptom. Patients suffering from burning mouth syndrome suffered from some psychical disturbances as well. The fact that depression and anxiety are closely connected with stomatopyrosis has been scientifically confirmed. The data which systematically led to this conclusion suggest the possibility of the existence of a psychogenic disturbance as an aetiological factor which leads to stomatopyrosis. Research which might be conducted in order to relate psychogenic disturbances with stomatopyrosis by means of various drugs and procedures, might provide an insight into the relatedness of these factors, which would enable us to treat the cause and not the consequence. This research has been directed towards establishing this "relatedness" by means of psychopharmatics and psychotherapy, and has been confirmed by means of psychological depression and anxiety tests. The research has been conducted on 120 respondents suffering from stomatopyrosis, who were also, as previously diagnosed, suffering from a psychical disturbance. The respondents were divided into 4 groups. Each group contained 30 respondents suffering from stomatopyrosis as the basic symptom, but with different psychogenic disturbances. These groups were: 1) antidepressants, 2) anxiolytics, 3) autogenic training and 4) control group. A detailed clinical and psychiatric check-up was conducted before the treatment started, and was repeated several times in different intervals: after a month, after two months and after four months. Respondents are still undergoing a therapy. Subjective assessment of the intensity of the burning sensation was obtained according to Visual analogue scale and two psychological questionnaires (depression test and anxiety test). Conclusion is: 1) Antidepressants and anxiolytic drugs have a prominent role in the treatment of stomatopyrosis

An analysis of quality of life (QOL) in patients with epilepsy and comorbid psychogenic nonepileptic seizures (PNES) after vagus nerve stimulation (VNS).

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Vivas, Andrew C; Reitano, Christian J; Waseem, Hena; Benbadis, Selim R; Vale, Fernando L

2017-08-01

Patients with epilepsy (PWE) may suffer from comorbid psychogenic nonepileptic seizures (PNES). The efficacy of vagus nerve stimulation (VNS) in the treatment of epilepsy and depression is established, however the impact on PNES is unknown. Since many patients with PNES have comorbid depression, we explored the impact on quality of life (QOL) that VNS has on PWE and PNES. The video electroencephalogram (vEEG) of all patients who underwent VNS at our institution was reviewed. Patients diagnosed with both psychogenic seizures and epileptic seizures on their vEEG were included in this study. These patients were contacted, and given a QOLIE-31 survey to assess their quality of life after VNS. Patients also completed a separate survey created by our group to categorize the quartile of their improvement. Pre-operative psychiatric disease was retrospectively reviewed. From a period of 2001 to 2016, 518 patients underwent placement of VNS for drug resistant epilepsy (DRE) at our institution. In total, 16 patients were diagnosed with both epilepsy and PNES. 11/16 patients responded to our questionnaire and survey. 9 out of 11 patients felt that their epileptic seizures had improved after VNS, while 7 of the 11 patients felt that their psychogenic episodes had improved. 2(28.6%), 1 (14.3%), and 4 (57.1%) of participants said their PNES improved by 25-50%, 50-75%, and 75-100%, respectively. 3(27.3%), 3 (27.3%), 1 (9.1%), and 4 (36.4%) of the participants said their epileptic seizures improved by 0-25%, 25-50%, 50-75%, and 75-100%, respectively. The average overall score for quality of life for the study participants was found to be 51 (±8) out of 100. Patients with epilepsy and comorbid PNES may benefit from VNS. It is unclear whether the benefit is conferred strictly from decreased epileptic seizure burden. The possible effect on PNES may be related to the known effect of VNS on depression. Further studies are necessary to elucidate the role of VNS in the treatment of PNES

Proposal for best practice in the use of video-EEG when psychogenic non-epileptic seizures are a possible diagnosis

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Kimberley Whitehead

Full Text Available The gold-standard for the diagnosis of psychogenic non-epileptic seizures (PNES is capturing an attack with typical semiology and lack of epileptic ictal discharges on video-EEG. Despite the importance of this diagnostic test, lack of standardisation has resulted in a wide variety of protocols and reporting practices. The goal of this review is to provide an overview of research findings on the diagnostic video-EEG procedure, in both the adult and paediatric literature. We discuss how uncertainties about the ethical use of suggestion can be resolved, and consider what constitutes best clinical practice. We stress the importance of ictal observation and assessment and consider how diagnostically useful information is best obtained. We also discuss the optimal format of video-EEG reports; and of highlighting features with high sensitivity and specificity to reduce the risk of miscommunication. We suggest that over-interpretation of the interictal EEG, and the failure to recognise differences between typical epileptic and nonepileptic seizure manifestations are the greatest pitfalls in neurophysiological assessment of patients with PNES. Meanwhile, under-recognition of semiological pointers towards frontal lobe seizures and of the absence of epileptiform ictal EEG patterns during some epileptic seizure types (especially some seizures not associated with loss of awareness, may lead to erroneous PNES diagnoses. We propose that a standardised approach to the video-EEG examination and the subsequent written report will facilitate a clear communication of its import, improving diagnostic certainty and thereby promoting appropriate patient management. Keywords: Psychogenic nonepileptic seizures, Nonepileptic attack disorder, Suggestion, EEG

Psychogenic non-epileptic seizures and psychoanalytical treatment: results

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Niraldo de Oliveira Santos

2014-12-01

Full Text Available Background: the occurrence of psychogenic non-epileptic seizures (PNES is estimated to be between 2 to 33 cases in every 100,000 inhabitants. The number of patients with PNES reaches 19% of those treated as epileptics. Patients with PNES are treated as if they had intractable epilepsy, with unsatisfactory results even after medication treatment is used to its maximum. The aim of this study is to present the effects of individual psychoanalytical treatment in patients with PNES, assessing its impact in the evolution of the clinical picture and its association with sex, time of disease, social, psychological and professional harm, as well as going through with treatment. Methods: The case base was composed of 37 patients with PNES. The diagnosis was reached with video-EEG monitoring. Psychoanalytical treatment was carried out through 12 months of weekly sessions timed for around 50-minutes each, in a total of 48 individual sessions. Results: This study found a high rate of success in the treatment of PNES patients. 29.7% (n=11 of patients had cessation or cure of symptoms and 51.4% (n=19 had a decrease in the number of episodes. There is an association between cessation or decrease in the number of episodes and sex (p<0.01, religion (p<0.01 and concluding treatment (p<0.01. Conclusion: Individual psychoanalytical treatment applied to patients with PNES is considered effective and can be an essential form of assistance for the reduction or cessation of episodes.

Wake behind circular cylinder excited by spanwise periodic disturbances

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Sasaki, Yudai; Uchida, Iwami; Sakakibara, Jun

2017-11-01

We experimentally investigated the influence of flow control of the wake behind a circular cylinder excited by temporal periodic disturbances with spanwise phase variations using plasma actuators, motivated by reducing drag forces by suppressing development of large scale vortices. Plasma actuators were segmented in the spanwise direction, phase differences were given to adjacent electrodes. This experiment was conducted at Re =8000 and the wake was visualized by PIV. Compared to without forcing, when the phase difference is 180° and non-dimensional forcing frequency is higher than approximately 1.0, small vortices induced by periodic disturbance emerged in the free shear layer and the drag forces decreased.

Planum sphenoidale meningioma leading to visual disturbance.

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Lutwak, Nancy; Dill, Curt; Wieczorek, Rosemary

2011-08-31

A 60-year-old male presented with complaints of dizziness, which worsened with fatigue and a sense his balance was 'off'. Initial physical examination was negative and the laboratory testing was unremarkable. Within weeks, the patient developed bilateral visual field deficits. MRI revealed an extra-axial mass which extended into the pituitary fossa and caused compression of the pituitary gland. The pituitary stalk was displaced posteriorly and the optic chiasm was compressed with displacement superiorly and posteriorly. The patient underwent a surgical resection. Diabetes insipidus developed postoperatively requiring a vasopressin drip. He also developed hypopituitarism after the resection with hypothyroidism, hypoadrenalism and hypogonadism. The patient requires testosterone, levothyroxine and hydrocortisone replacement and has mild residual bitemporal hemianopsia.

SUCCES AT SCHOOL IN VISUALLY IMPAIRED CHILDREN

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Stanika DIKIC

1998-04-01

Full Text Available The research included 200 visually impaired children of primary school during the period from 1992 to 1996. By means of adequate instruments we have tested the relation between the success at school of partially seeing children and hyperkinetic behavior, active and passive vocabulary richness, visuo-motoric coordination and the maturity of handwriting. Besides the already known factors (intellectual level, specific learning disturbances, emotional and neurotic disturbances, cultural deprivation, the success in class depends very much on the intensity of hyperkinetic behavior as well as its features: unstable attention, impulsiveness and hyperactivity. Visual-motor coordination eye-hand and the maturity of handwriting have a strong influence on their success at school.

Psychogenic non-epileptic seizures: our video-EEG experience.

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Nežádal, Tomáš; Hovorka, Jiří; Herman, Erik; Němcová, Iveta; Bajaček, Michal; Stichová, Eva

2011-09-01

The aim of our study was to assess the number of psychogenic non-epileptic seizures (PNES) in our patients with a refractory seizure disorder, to determine the 'typical' PNES semiology using video-EEG monitoring and describe other PNES parameters. We evaluated prospectively 596 patients with pharmacoresistant seizures. All these patients underwent continuous video-EEG monitoring. In consenting patients, we used suggestive seizure provocation. We assessed seizure semiology, interictal EEG, brain MRI, psychiatric co-morbidities, personality profiles, and seizure outcome. In the sample of 596 monitored patients, we detected 111 (19.3%) patients with PNES. Of the 111 patients with PNES, 86.5% had spontaneous and 76.5% had provoked seizures. The five most typical symptoms were: initially closed eyelids (67.6%), rapid tremor (47.7%), asynchronous limb movement (37.8%), preictal pseudosleep (33.3%), and side-to-side head movement (32.4%). Interictal EEG was rated as abnormal in 46.2% and with epileptiform abnormality in 9%. Brain MRI was abnormal in 32 (28.8%) patients. Personality disorders (46.8%), anxiety (39.6%), and depression (12.6%) were the most frequent additional psychiatric co-morbidities. PNES outcome after at least 2 years is reported; 22.5% patients was seizure-free; one-third had markedly reduced seizure frequency. We have not seen any negative impact of the provocative testing on the seizure outcome. Video-EEG monitoring with suggestive seizure provocation supported by clinical psychiatric and psychological evaluation significantly contributes to the correct PNES diagnosis, while interictal EEG and brain MRI are frequently abnormal. Symptoms typical for PNES, as opposed to epileptic seizures, could be distinguished.

Clinical study of the visual field defects caused by occipital lobe lesions.

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Ogawa, Katsuhiko; Ishikawa, Hiroshi; Suzuki, Yutaka; Oishi, Minoru; Kamei, Satoshi

2014-01-01

The central visual field is projected to the region from the occipital tip to the posterior portion of the medial area in the striate cortex. However, central visual field disturbances have not been compared with the location of the lesions in the striate cortex. Thirteen patients with visual field defects caused by partial involvement of the striate cortex were enrolled. The lesions were classified according to their location into the anterior portion, the posterior portion of the medial area, and the occipital tip. Visual field defects were examined by the Goldmann perimetry, the Humphrey perimetry and the auto-plot tangent screen. We defined a defect within the central 10° of vision as a central visual field disturbance. The visual field defects in 13 patients were compared with the location of their lesions in the striate cortex. The medial area was involved in 7 patients with no involvement of the occipital tip. In 2 of them, peripheral homonymous hemianopia without central visual field disturbance was shown, and their lesions were located only in the anterior portion. One patient with a lesion in the posterior portion alone showed incomplete central homonymous hemianopia. Three of 4 patients with lesions located in both the anterior and posterior portions of the medial area showed incomplete central homonymous hemianopia and peripheral homonymous hemianopia. The occipital tip was involved in 6 patients. Five of them had small lesions in the occipital tip alone and showed complete central homonymous hemianopia or quadrantanopia. The other patient with a lesion in the lateral posterior portion and bilateral occipital tip lesions showed bilateral slight peripheral visual field disturbance in addition to complete central homonymous hemianopia on both sides. Lesions in the posterior portion of the medial area as well as the occipital tip caused central visual field disturbance in our study, as indicated in previous reports. Central homonymous hemianopia tended to

Disturbance hydrology: Preparing for an increasingly disturbed future

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Mirus, Benjamin B.; Ebel, Brian A.; Mohr, Christian H.; Zegre, Nicolas

2017-01-01

This special issue is the result of several fruitful conference sessions on disturbance hydrology, which started at the 2013 AGU Fall Meeting in San Francisco and have continued every year since. The stimulating presentations and discussions surrounding those sessions have focused on understanding both the disruption of hydrologic functioning following discrete disturbances, as well as the subsequent recovery or change within the affected watershed system. Whereas some hydrologic disturbances are directly linked to anthropogenic activities, such as resource extraction, the contributions to this special issue focus primarily on those with indirect or less pronounced human involvement, such as bark-beetle infestation, wildfire, and other natural hazards. However, human activities are enhancing the severity and frequency of these seemingly natural disturbances, thereby contributing to acute hydrologic problems and hazards. Major research challenges for our increasingly disturbed planet include the lack of continuous pre- and post-disturbance monitoring, hydrologic impacts that vary spatially and temporally based on environmental and hydroclimatic conditions, and the preponderance of overlapping or compounding disturbance sequences. In addition, a conceptual framework for characterizing commonalities and differences among hydrologic disturbances is still in its infancy. In this introduction to the special issue, we advance the fusion of concepts and terminology from ecology and hydrology to begin filling this gap. We briefly explore some preliminary approaches for comparing different disturbances and their hydrologic impacts, which provides a starting point for further dialogue and research progress.

Disturbing forest disturbances

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Volney, W.J.A.; Hirsch, K.G. [Natural Resources Canada, Canadian Forest Service, Northern Forestry Centre, Edmonton, AB (Canada)

2005-10-01

This paper described the role that disturbances play in maintaining the ecological integrity of Canadian boreal forests. Potential adaptation options to address the challenges that these disturbances present were also examined. Many forest ecosystems need fire for regeneration, while other forests rely on a cool, wet disintegration process driven by insects and commensal fungi feeding on trees to effect renewal. While there are characteristic natural, temporal and spatial patterns to these disturbances, recent work has demonstrated that the disturbances are being perturbed by climatic change that has been compounded by anthropogenic disturbances in forests. Fire influences species composition and age structure, regulates forest insects and diseases, affects nutrient cycling and energy fluxes, and maintains the productivity of different habitats. Longer fire seasons as a result of climatic change will lead to higher intensity fires that may more easily evade initial attacks and become problematic. Fire regimes elevated beyond the range of natural variation will have a dramatic effect on the regional distribution and functioning of forest ecosystems and pose a threat to the safety and prosperity of people. While it was acknowledged that if insect outbreaks were to be controlled on the entire forest estate, the productivity represented by dead wood would be lost, it was suggested that insects such as the forest tent caterpillar and the spruce bud worm may also pose a greater threat as the climate gets warmer and drier. Together with fungal associates, saproxylic arthropods are active in nutrient cycling and ultimately determine the fertility of forest sites. It was suggested that the production of an age class structure and forest mosaic would render the forest landscape less vulnerable to the more negative aspects of climate change on vegetation response. It was concluded that novel management design paradigms are needed to successfully reduce the risk from threats

Changes in Mothers' Experiences of Receiving an Autism Diagnosis: A Contextualized Case Study

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Hornstein, Shana

2011-01-01

Autism has a unique history. The definition has broadened and changed over time, from an emotional disturbance with psychogenic origins to a neurodevelopmental disability with suspected environmental and genetic origins. Diagnosis occurs later than children born with obvious disabilities such as cerebral palsy or Down syndrome, but earlier than…

Regulation of emotions in psychogenic nonepileptic seizures.

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Urbanek, Monika; Harvey, Martin; McGowan, John; Agrawal, Niruj

2014-08-01

Despite the long history of psychogenic nonepileptic seizures (PNES), relatively little is known about the mechanisms that cause and maintain this condition. Emerging research evidence suggests that patients with PNES might have difficulties in regulating their emotions. However, much remains to be learned about the nature of these difficulties and the emotional responses of individuals with PNES. This study aimed to gain a detailed understanding of emotion regulation processes in patients with PNES by examining differences between patients with PNES and a healthy control group with regard to intensity of emotional reactions, understanding of one's emotional experience, beliefs about emotions, and managing emotions by controlling emotional expression. A cross-sectional design was used to compare the group with PNES (n=56) and the healthy control group (n=88) on a range of self-report measures. Participants with a diagnosis of PNES reported significantly poorer understanding of their emotions, more negative beliefs about emotions, and a greater tendency to control emotional expression compared to the control group. While intensity of emotions did not discriminate between the groups, poor understanding and negative beliefs about emotions were found to be significant predictors of PNES, even after controlling for age, education level, and emotional distress. Furthermore, the presence of some emotion regulation difficulties was associated with self-reported seizure severity. The results of this study are largely consistent with previous literature and provide evidence for difficulties in emotion regulation in patients with PNES. However, this research goes further in bringing together different aspects of emotion regulation, including beliefs about emotions, which have not been examined before. As far as it is known, this is the first study to suggest that levels of alexithymia in a population with PNES are positively associated with self-reported seizure severity. The

Psychogenic or neurogenic origin of agrammatism and foreign accent syndrome in a bipolar patient: a case report

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Fossard Marion

2007-01-01

Full Text Available Abstract Background Foreign accent syndrome (FAS is a rare speech disorder characterized by the appearance of a new accent, different from the speaker's native language and perceived as foreign by the speaker and the listener. In most of the reported cases, FAS follows stroke but has also been found following traumatic brain injury, cerebral haemorrhage and multiple sclerosis. In very few cases, FAS was reported in patients presenting with psychiatric disorders but the link between this condition and FAS was confirmed in only one case. Case presentation In this report, we present the case of FG, a bipolar patient presenting with language disorders characterized by a foreign accent and agrammatism, initially categorized as being of psychogenic origin. The patient had an extensive neuropsychological and language evaluation as well as brain imaging exams. In addition to FAS and agrammatism, FG also showed a working memory deficit and executive dysfunction. Moreover, these clinical signs were related to altered cerebral activity on an FDG-PET scan that showed diffuse hypometabolism in the frontal, parietal and temporal lobes bilaterally as well as a focal deficit in the area of the anterior left temporal lobe. When compared to the MRI, these deficits were related to asymmetric atrophy, which was retrospectively seen in the left temporal and frontal opercular/insular region without a focal lesion. Discussion To our knowledge, FG is the first case of FAS imaged with an 18F-FDG-PET scan. The nature and type of neuropsychological and linguistic deficits, supported by neuroimaging data, exclude a neurotoxic or neurodegenerative origin for this patient's clinical manifestations. For similar reasons, a psychogenic etiology is also highly improbable. Conclusion To account for the FAS and agrammatism in FG, various explanations have been ruled out. Because of the focal deficit seen on the brain imaging, involving the left insular and anterior temporal cortex

Psychogenic or neurogenic origin of agrammatism and foreign accent syndrome in a bipolar patient: a case report.

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Poulin, Stéphane; Macoir, Joël; Paquet, Nancy; Fossard, Marion; Gagnon, Louis

2007-01-04

Foreign accent syndrome (FAS) is a rare speech disorder characterized by the appearance of a new accent, different from the speaker's native language and perceived as foreign by the speaker and the listener. In most of the reported cases, FAS follows stroke but has also been found following traumatic brain injury, cerebral haemorrhage and multiple sclerosis. In very few cases, FAS was reported in patients presenting with psychiatric disorders but the link between this condition and FAS was confirmed in only one case. In this report, we present the case of FG, a bipolar patient presenting with language disorders characterized by a foreign accent and agrammatism, initially categorized as being of psychogenic origin. The patient had an extensive neuropsychological and language evaluation as well as brain imaging exams. In addition to FAS and agrammatism, FG also showed a working memory deficit and executive dysfunction. Moreover, these clinical signs were related to altered cerebral activity on an FDG-PET scan that showed diffuse hypometabolism in the frontal, parietal and temporal lobes bilaterally as well as a focal deficit in the area of the anterior left temporal lobe. When compared to the MRI, these deficits were related to asymmetric atrophy, which was retrospectively seen in the left temporal and frontal opercular/insular region without a focal lesion. To our knowledge, FG is the first case of FAS imaged with an 18F-FDG-PET scan. The nature and type of neuropsychological and linguistic deficits, supported by neuroimaging data, exclude a neurotoxic or neurodegenerative origin for this patient's clinical manifestations. For similar reasons, a psychogenic etiology is also highly improbable. To account for the FAS and agrammatism in FG, various explanations have been ruled out. Because of the focal deficit seen on the brain imaging, involving the left insular and anterior temporal cortex, two brain regions frequently involved in aphasic syndrome but also in FAS, a

Application of a naturalistic psychogenic stressor in periadolescent mice: effect on serum corticosterone levels differs by strain but not sex

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Klein Laura C

2010-06-01

Full Text Available Abstract Background As a first step in determining whether psychogenic stressors might be incorporated into periadolescent mouse models of stress, we evaluated whether a commonly used psychogenic stressor, exposure to red fox urine, alters serum corticosterone levels in periadolescent C57BL/6J and DBA/2J mice. Findings In a 1-day experiment, forty-eight 38-day-old C57BL/6J (N = 12 males; N = 12 females and DBA/2J (N = 12 males; N = 12 females mice were exposed to 10-min of red fox urine via cotton ball (N = 12 C57BL/6J mice; N = 12 DBA/2J mice or to a non-saturated cotton ball (N = 12 C57BL/6J mice; N = 12 DBA/2J mice. All mice were sacrificed 15-min after cotton ball exposure and serum was collected for corticosterone assessment. Overall, there was a main effect for strain such that C57BL/6J male and female mice displayed higher corticosterone levels than did male and female DBA/2J mice. There were no main effects for sex or odor exposure. However, there was a significant strain by odor exposure interaction, whereby, within odor-exposed mice, DBA/2J mice displayed lower corticosterone levels (ng/mL compared to C57BL/6J mice, regardless of sex. Further, among DBA/2J mice, predator odor exposure reduced corticosterone levels compared to no odor exposure. Conclusions Findings indicate that mouse strain, but not sex, may play an important role in the efficacy of a predator odor among periadolescent mice.

Disturbance Hydrology: Preparing for an Increasingly Disturbed Future

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Mirus, Benjamin B.; Ebel, Brian A.; Mohr, Christian H.; Zegre, Nicolas

2017-12-01

This special issue is the result of several fruitful conference sessions on disturbance hydrology, which started at the 2013 AGU Fall Meeting in San Francisco and have continued every year since. The stimulating presentations and discussions surrounding those sessions have focused on understanding both the disruption of hydrologic functioning following discrete disturbances, as well as the subsequent recovery or change within the affected watershed system. Whereas some hydrologic disturbances are directly linked to anthropogenic activities, such as resource extraction, the contributions to this special issue focus primarily on those with indirect or less pronounced human involvement, such as bark-beetle infestation, wildfire, and other natural hazards. However, human activities are enhancing the severity and frequency of these seemingly natural disturbances, thereby contributing to acute hydrologic problems and hazards. Major research challenges for our increasingly disturbed planet include the lack of continuous pre and postdisturbance monitoring, hydrologic impacts that vary spatially and temporally based on environmental and hydroclimatic conditions, and the preponderance of overlapping or compounding disturbance sequences. In addition, a conceptual framework for characterizing commonalities and differences among hydrologic disturbances is still in its infancy. In this introduction to the special issue, we advance the fusion of concepts and terminology from ecology and hydrology to begin filling this gap. We briefly explore some preliminary approaches for comparing different disturbances and their hydrologic impacts, which provides a starting point for further dialogue and research progress.

Basal hypercortisolism and trauma in patients with psychogenic nonepileptic seizures.

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Bakvis, Patricia; Spinhoven, Philip; Giltay, Erik J; Kuyk, Jarl; Edelbroek, Peter M; Zitman, Frans G; Roelofs, Karin

2010-05-01

Several studies have indicated that psychogenic nonepileptic seizures (PNES) are associated with psychological trauma, but only a few studies have examined the associations with neurobiologic stress systems, such as the hypothalamus-pituitary-adrenal (HPA) axis and its end-product cortisol. We tested several relevant HPA-axis functions in patients with PNES and related them to trauma history. Cortisol awakening curve, basal diurnal cortisol, and negative cortisol feedback (using a 1 mg dexamethasone suppression test) were examined in 18 patients with PNES and 19 matched healthy controls (HCs) using saliva cortisol sampling on two consecutive days at 19 time points. Concomitant sympathetic nervous system (SNS) activity was assessed by analyzing saliva alpha-amylase (sAA). Patients with PNES showed significantly increased basal diurnal cortisol levels compared to HCs. This effect was driven mainly by patients reporting sexual trauma who showed a trend toward higher cortisol levels as compared to patients without a sexual trauma report. Importantly, the increased basal diurnal cortisol levels in patients were not explained by depression, medication, or smoking, or by current seizures or group differences in SNS activity. This is the first study showing that basal hypercortisolism in patients with PNES is independent of the acute occurrence of seizures. In addition, basal hypercortisolism was more pronounced in traumatized patients with PNES as compared to nontraumatized patients with PNES. These findings suggest that HPA-axis activity provides a significant neurobiologic marker for PNES.

Visual dysfunction in Parkinson’s disease

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Weil, Rimona S.; Schrag, Anette E.; Warren, Jason D.; Crutch, Sebastian J.; Lees, Andrew J.; Morris, Huw R.

2016-01-01

Patients with Parkinson’s disease have a number of specific visual disturbances. These include changes in colour vision and contrast sensitivity and difficulties with complex visual tasks such as mental rotation and emotion recognition. We review changes in visual function at each stage of visual processing from retinal deficits, including contrast sensitivity and colour vision deficits to higher cortical processing impairments such as object and motion processing and neglect. We consider changes in visual function in patients with common Parkinson’s disease-associated genetic mutations including GBA and LRRK2. We discuss the association between visual deficits and clinical features of Parkinson’s disease such as rapid eye movement sleep behavioural disorder and the postural instability and gait disorder phenotype. We review the link between abnormal visual function and visual hallucinations, considering current models for mechanisms of visual hallucinations. Finally, we discuss the role of visuo-perceptual testing as a biomarker of disease and predictor of dementia in Parkinson’s disease. PMID:27412389

Predictive Validity And Usefulness Of Visual Scanning Task In Hiv ...

African Journals Online (AJOL)

The visual scanning task is a useful screening tool for brain damage in HIV/AIDS by inference from impairment of visual information processing and disturbances in perceptual mental strategies. There is progressive neuro-cognitive decline as the disease worsens. Keywords: brain, cognition, HIV/AIDS, predictive validity, ...

Clinical characteristics and outcome of patients diagnosed with psychogenic nonepileptic seizures: a 5-year review.

LENUS (Irish Health Repository)

O'Sullivan, S S

2012-02-03

OBJECTIVE: The goal of this article was to describe the clinical characteristics and outcomes of patients diagnosed with psychogenic nonepileptic seizures (PNES). METHODS: We conducted a retrospective review of patients diagnosed with PNES in a 5-year period. RESULTS: Fifty patients with PNES were identified, giving an estimated incidence of 0.91\\/100,000 per annum. Thirty-eight were included for review, 15 of whom were male (39%). Eighteen patients had been diagnosed with epilepsy as well as PNES (47%). We demonstrated a gender difference in our patients, with males having higher seizure frequencies, more antiepileptic drug use, and a longer interval before diagnosis of PNES. Females were diagnosed with other conversion disorders more often than males. Impaired social function was observed in PNES, as was resistance to psychological interventions with a subsequent poor response to treatments. CONCLUSIONS: PNES remains a difficult condition to treat, and may affect males in proportions higher than those described in previous studies.

Cerebral Activity Changes in Different Traditional Chinese Medicine Patterns of Psychogenic Erectile Dysfunction Patients.

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Liu, Qi; Zhang, Peihai; Pan, Junjie; Li, Zhengjie; Liu, Jixin; Li, Guangsen; Qin, Wei; You, Yaodong; Yu, Xujun; Sun, Jinbo; Dong, Minghao; Gong, Qiyong; Guo, Jun; Chang, Degui

2015-01-01

Background. Pattern differentiation is the foundation of traditional Chinese medicine (TCM) treatment for erectile dysfunction (ED). This study aims to investigate the differences in cerebral activity in ED patients with different TCM patterns. Methods. 27 psychogenic ED patients and 27 healthy subjects (HS) were enrolled in this study. Each participant underwent an fMRI scan in resting state. The fractional amplitude of low-frequency fluctuation (fALFF) was used to detect the brain activity changes in ED patients with different patterns. Results. Compared to HS, ED patients showed an increased cerebral activity in bilateral cerebellum, insula, globus pallidus, parahippocampal gyrus, orbitofrontal cortex (OFC), and middle cingulate cortex (MCC). Compared to the patients with liver-qi stagnation and spleen deficiency pattern (LSSDP), the patients with kidney-yang deficiency pattern (KDP) showed an increased activity in bilateral brainstem, cerebellum, hippocampus, and the right insula, thalamus, MCC, and a decreased activity in bilateral putamen, medial frontal gyrus, temporal pole, and the right caudate nucleus, OFC, anterior cingulate cortex, and posterior cingulate cortex (P emotion-related regions, including prefrontal cortex and cingulated cortex.

Transience after disturbance: Obligate species recovery dynamics depend on disturbance duration.

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Singer, Alexander; Johst, Karin

2017-06-01

After a disturbance event, population recovery becomes an important species response that drives ecosystem dynamics. Yet, it is unclear how interspecific interactions impact species recovery from a disturbance and which role the disturbance duration (pulse or press) plays. Here, we analytically derive conditions that govern the transient recovery dynamics from disturbance of a host and its obligately dependent partner in a two-species metapopulation model. We find that, after disturbance, species recovery dynamics depend on the species' role (i.e. host or obligately dependent species) as well as the duration of disturbance. Host recovery starts immediately after the disturbance. In contrast, for obligate species, recovery depends on disturbance duration. After press disturbance, which allows dynamics to equilibrate during disturbance, obligate species immediately start to recover. Yet, after pulse disturbance, obligate species continue declining although their hosts have already begun to increase. Effectively, obligate species recovery is delayed until a necessary host threshold occupancy is reached. Obligates' delayed recovery arises solely from interspecific interactions independent of dispersal limitations, which contests previous explanations. Delayed recovery exerts a two-fold negative effect, because populations continue declining to even smaller population sizes and the phase of increased risk from demographic stochastic extinction in small populations is prolonged. We argue that delayed recovery and its determinants -species interactions and disturbance duration - have to be considered in biodiversity management. Copyright © 2017 Elsevier Inc. All rights reserved.

Sensory Disturbances, but Not Motor Disturbances, Induced by Sensorimotor Conflicts Are Increased in the Presence of Acute Pain

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Clémentine Brun

2017-07-01

Full Text Available Incongruence between our motor intention and the sensory feedback of the action (sensorimotor conflict induces abnormalities in sensory perception in various chronic pain populations, and to a lesser extent in pain-free individuals. The aim of this study was to simultaneously investigate sensory and motor disturbances evoked by sensorimotor conflicts, as well as to assess how they are influenced by the presence of acute pain. It was hypothesized that both sensory and motor disturbances would be increased in presence of pain, which would suggest that pain makes body representations less robust. Thirty healthy participants realized cyclic asymmetric movements of flexion-extension with both upper limbs in a robotized system combined to a 2D virtual environment. The virtual environment provided a visual feedback (VF about movements that was either congruent or incongruent, while the robotized system precisely measured motor performance (characterized by bilateral amplitude asymmetry and medio-lateral drift. Changes in sensory perception were assessed with a questionnaire after each trial. The effect of pain (induced with capsaicin was compared to three control conditions (no somatosensory stimulation, tactile distraction and proprioceptive masking. Results showed that while both sensory and motor disturbances were induced by sensorimotor conflicts, only sensory disturbances were enhanced during pain condition comparatively to the three control conditions. This increase did not statistically differ across VF conditions (congruent or incongruent. Interestingly however, the types of sensations evoked by the conflict in the presence of pain (changes in intensity of pain or discomfort, changes in temperature or impression of a missing limb were different than those evoked by the conflict alone (loss of control, peculiarity and the perception of having an extra limb. Finally, results showed no relationship between the amount of motor and sensory

Visual complications following irradiation for pituitary adenomas and craniopharyngiomas

International Nuclear Information System (INIS)

Harris, J.R.; Levene, M.B.

1976-01-01

Of 55 patients with pituitary adenomas or craniopharyngiomas treated with irradiation, a retrospective study revealed that 5 sustained a visual loss compatible with radiation damage to the optic nerve. No patient who received less than 250 rads/day fractions showed such visual loss. Within the range of total dosages used in this series, total dose was not an important determinant of this complication. The time to occurrence of visual disturbance ranged from 5 to 34 months following therapy

Influence of visual observational conditions on tongue motor learning

DEFF Research Database (Denmark)

Kothari, Mohit; Liu, Xuimei; Baad-Hansen, Lene

2016-01-01

To investigate the impact of visual observational conditions on performance during a standardized tongue-protrusion training (TPT) task and to evaluate subject-based reports of helpfulness, disturbance, pain, and fatigue due to the observational conditions on 0-10 numerical rating scales. Forty...... regarding the level of disturbance, pain or fatigue. Self-observation of tongue-training facilitated behavioral aspects of tongue motor learning compared with model-observation but not compared with control....

Semiology of psychogenic nonepileptic seizures: An international cross-cultural study.

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Asadi-Pooya, Ali A; Valente, Kette; Alessi, Ruda; Tinker, Jennifer

2017-10-01

We compared the semiology of psychogenic nonepileptic seizures (PNES) between patients from the USA and Brazil. This international cross-cultural comparative study may expand understanding of PNES across the borders. We retrospectively investigated all patients with PNES admitted to one epilepsy center in the USA and one in Brazil. We classified their seizures into four classes: generalized motor, akinetic, focal motor, and subjective symptoms. All patients were interviewed by an epileptologist in both countries and were administered psychological assessment measures, including questions about PNES risk factors. For the statistical analyses, we compared patients from the two nations. Eighty-nine patients (49 from the USA and 40 from Brazil) were studied. Patients from the two countries were not significantly different with regard to sex and age, but patients from Brazil had earlier age at onset (26years vs. 34years; P=0.004) and a significantly greater delay in diagnosis (9.9years vs. 5.6years; P=0.001). Some characteristics of PNES were different between the two groups; patients from the USA had generally more seizure types and more often reported subjective seizures (55% in the USA vs. 10% in Brazil; P=0.0001). Clinical and historical characteristics of the patients were not significantly different. Delay in diagnosis of PNES may represent a major factor in resource-limited countries. Large multicenter cross-cultural studies may reveal subtle but significant cross-cultural differences with respect to the semiological, clinical, and historical aspects of PNES; however, patients with PNES share more similarities than differences. Copyright © 2017 Elsevier Inc. All rights reserved.

Pain, Sleep Disturbance, and Quality of Life Among Palestinian Patients Diagnosed with Cancer.

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Dreidi, Mu'taz M; Hamdan-Mansour, Ayman M

2016-12-01

The objective of this descriptive study is to explore the relationships between pain, sleep disturbance, and quality of life among Palestinian patients diagnosed with cancer in the West Bank. A cross-sectional, descriptive-correlational design was used to collect data from 184 patients with cancer. The quality of life questionnaire, visual analogue pain scale, and physical health status were used in data collection. The results showed that the mean score for pain was 5, the best functioning was for cognitive scale (M = 75, SD = 29), the worst symptoms experienced by patients was appetite loss (M = 47, SD = 35), a moderate global health status (M = 53, SD = 27), and the mean for sleep disturbance was 43 (SD = 35). Pain and sleep disturbance showed high negative correlations with functional scales of quality of life and positive with symptom scales. The findings showed that the co-occurrence of pain and sleep disturbance was negatively correlated with quality of life (QoL) and positively with symptom scales. The regression analysis revealed that pain and sleep disturbance accounted for a significant proportion of variance in the QoL (p quality among Palestinian patients with cancer.

Evolution Of The Cloud Field And Wind Structure Of Ntb Disturbance

Science.gov (United States)

Barrado-Izagirre, Naiara; Pérez-Hoyos, S.; García-Melendo, E.; Sánchez-Lavega, A.

2009-09-01

The banded visual aspect of cloud patterns in Jupiter hides markedly turbulent areas visible in high resolution images. The North Temperate Belt (NTB) at 21° N planetocentric latitude where the most intense Jovian jet resides (with speeds of 160 - 180 m/s) is a region of particular interest because it is known to suffer almost every 15 years an eruption or disturbance which dramatically changes its appearance. This phenomenon is known as NTB Disturbance (NTBD). The last one of such disturbances happened in 2007 and was captured by the Hubble Space Telescope and with lower resolution by the "International Outer Planet Watch” (IOPW) network [Sánchez-Lavega et al., 2008. Depth of a strong Jovian jet from a planetary-scale disturbance driven by storms, Nature 451.]. In this work we make use of these observations to characterize the morphology of the disturbed cloud field in the wake of the plumes which originated the perturbation. This is done mostly in terms of the brightness spectral distribution in order to characterize the typical spatial frequency of the perturbation and its wavy and turbulent nature. In addition we make a comparison of the jet profile in the NTB just after the disturbance ended (June 2007) with one obtained year later (July 2008). It shows that a change occurred in its anticyclonic side producing a reinforced westward jet at 17°N with a speed change of 30 m/s. Acknowledgments: This work has been funded by Spanish MEC AYA2006-07735 with FEDER support and Grupos Gobierno Vasco IT-464-07

Detection of transient disturbing signals on PC boards

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S. Korte

2008-05-01

Full Text Available This paper shows a possibility to visualize signal propagation in electronic circuits. Instead of using various galvanic measurement points all over the circuit, a test method is shown which measures the radiated field of the printed circuit board. By use of a 2-dimensional positionable field probe it is possible to get an overview over the signals running on the different parts of the PCB. In order to measure transient disturbing signals and distinguish them from normal device operation, problems of probe design and triggering need to be discussed.

The opinion of the general practitioner toward clinical management of patients with psychogenic nonepileptic seizures.

LENUS (Irish Health Repository)

O'Sullivan, S S

2012-02-03

OBJECTIVE: The purpose of this work was to assess the opinion of general practitioners (GPs) regarding the diagnosis of psychogenic nonepileptic seizures (PNES) and the role they feel they should play in the management of the disorder. METHODS: Patients with PNES were identified from hospital records. Seizure and patient characteristics were recorded. Their GPs were surveyed regarding their understanding of the diagnosis and ongoing management of PNES. RESULTS: Twenty-three patients were identified over a 3-year period as having been diagnosed with PNES. Sixty-five percent of GPs agreed with the diagnosis, and when asked to grade their understanding of the diagnosis (poor = 1, excellent = 10), the mean score was 5.7 (+\\/-SD 2.3). Thirty-five percent of GPs felt psychological input was of benefit to their patients. Fifty-two percent of GPs felt comfortable following up these patients, either with or without neurology outpatient services. CONCLUSIONS: PNES remains a difficult disease to manage. There is a high level of uncertainty regarding the optimum management of PNES among primary care physicians, for which further education is needed.

Number of patient-reported allergies helps distinguish epilepsy from psychogenic nonepileptic seizures.

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Robbins, Nathaniel M; Larimer, Phillip; Bourgeois, James A; Lowenstein, Daniel H

2016-02-01

Psychogenic nonepileptic seizures (PNES) are relatively common, accounting for 5-40% of visits to tertiary epilepsy centers. Inpatient video-electroencephalogram (vEEG) monitoring is the gold standard for diagnosis, but additional positive predictive tools are necessary given vEEG's relatively scarce availability. In this study, we investigated if the number of patient-reported allergies distinguishes between PNES and epilepsy. Excessive allergy-reporting, like PNES, may reflect somatization. Using electronic medical records, ICD-9 codes, and text-identification algorithms to search EEG reports, we identified 905 cases of confirmed PNES and 5187 controls with epilepsy but no PNES. Patients with PNES averaged more self-reported allergies than patients with epilepsy alone (1.93 vs. 1.00, pallergies, each additional allergy linearly increased the percentage of patients with PNES by 2.98% (R(2)=0.71) such that with ≥12 allergies, 12/28 patients (42.8%) had PNES compared to 349/3368 (11.6%) of the population with no allergies (odds ratio=6.49). This relationship remained unchanged with logistic regression analysis. We conclude that long allergy lists may help identify patients with PNES. We hypothesize that a tendency to inaccurately self-report allergies reflects a maladaptive externalization of psychologic distress and that a similar mechanism may be responsible for PNES in some patients with somatic symptom disorder. Copyright © 2015 Elsevier Inc. All rights reserved.

Clinical spectrum of psychogenic non epileptic seizures in children; an observational study.

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Madaan, Priyanka; Gulati, Sheffali; Chakrabarty, Biswaroop; Sapra, Savita; Sagar, Rajesh; Mohammad, Akbar; Pandey, R M; Tripathi, Manjari

2018-07-01

The current study was designed to analyze the clinical spectrum of Psychogenic non-epileptic seizures (PNES) in children. Children aged 6-16years with clinically suspected PNES, confirmed by short-term VEEG (STVEEG{video electroencephalogram}) and induction were classified as per Seneviratne classification. Stressors, associated co morbidities, Verbal IQ (Intelligence Quotient) and behavioral abnormalities were assessed using HTP(House tree person) test, DSM IV (Diagnostic and statistical manual of mental disorders) TR criteria, MISIC (Malin intelligence scale for Indian children) and CBCL (Child behaviour checklist). Eighty children with PNES {45 boys; mean age: 10.5 (±1.6) years} were enrolled. Median delay in diagnosis was 5 months {IQR(interquartile range)- 0.5 to 48 months}) and 45% patients were already on AEDs (antiepileptic drugs). Commonest semiology was dialeptic (42.5%), followed by mixed (28.8%), motor (15%) and nonepileptic aura (13.8%). Family stressors were the commonest followed by school related issues. The most common psychiatric comorbidity was adjustment disorder. Somatic complaints were observed in 50% children. Dialeptic PNES is commonest in children. In resource constrained settings, STVEEG along with induction is a reliable method to diagnose PNES. A comprehensive assessment protocol (including assessment of stressors) is needed for holistic management of pediatric PNES. Copyright © 2018 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

Sleep disturbance relates to neuropsychological functioning in late-life depression.

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Naismith, Sharon L; Rogers, Naomi L; Lewis, Simon J G; Terpening, Zoë; Ip, Tony; Diamond, Keri; Norrie, Louisa; Hickie, Ian B

2011-07-01

Sleep-wake disturbance in older people is a risk factor for depression onset and recurrence. The aim of this study was to determine if objective sleep-wake disturbance in late-life depression relates to neuropsychological functioning. Forty-four older patients with a lifetime history of major depression and 22 control participants underwent psychiatric, medical and neuropsychological assessments. Participants completed self-report sleep measures, sleep diaries and wore wrist actigraphy for two weeks. Outcome measures included sleep latency, the number and duration of nocturnal awakenings and the overall sleep efficiency. Patients with depression had a greater duration of nocturnal awakenings and poorer sleep efficiency, in comparison to control participants. Sleep disturbance in patients was associated with greater depression severity and later ages of depression onset. It also related to poorer psychomotor speed, poorer verbal and visual learning, poorer semantic fluency as well as poorer performance on tests of executive functioning. These relationships largely remained significant after controlling for depression and estimated apnoea severity. This sample had only mild levels of depression severity and results require replication in patients with moderate to severe depression. The inclusion of polysomnography and circadian markers would be useful to delineate the specific features of sleep-wake disturbance that are critical to cognitive performance. Sleep-wake disturbance in older patients with depression is related to neuropsychological functioning and to later ages of illness onset. This study suggests that common neurobiological changes may underpin these disease features, which may, in turn, warrant early identification and management. Copyright © 2011 Elsevier B.V. All rights reserved.

Analysis of AVS-penogram in 3000 impotent patients

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Minn, Young Guy; Choi, Hyung Ki [Yonsei University College of Medicine, Seoul (Korea, Republic of)

1994-09-01

Audio visual simulation penogram(AVS-penogram) is used as a screening method for evaluation of erectile dysfunction. In this study, 3000 patients were evaluated from Dec. 1986 to Dec. 1992 and finally diagnosed by comprehensive diagnostic methods. The patients were classified according to AVS-penogram curves into 4 types and correlated with the patient`s final diagnosis. For 800 patients who were evaluated with combined AVS-penogram and NPT monitoring, compatibility ratios between psychogenic and organic group were compared. After correlating each of the curve type with the patients and comparing erotic and nocturnal erection, following results were obtained. 1. The mean age of the patients was 41.25 years. 2. The overall rate of final diagnosis were 57.5%, 14.3%, 8.9% in psychogenic, arteriogenic and veogenic impotence. 3. Type I group was proved as psychogenic impotence in 87% of the patients. 4. Type IIA group was proved as organic impotence in 79% of the patients and most of them had neurogenic and arteriogenic impotence. 5. Type IIB group was proved as psychogenic impotence in 51%, organic impotence in 49% of the patients. Among the organic impotence group, most of them had arteriogenic, venogenic and neurogenic impotence. The difference of both group was statically insignificant. 6. Type IIC group was proved as psychogenic impotence in 39%, organic impotence in 61% of the patients. Further studies are needed for sub-classification of both groups. 7. The compatibility ratio of the AVS-penogram and NPTM was 85.9% in psychogenic group with normal finding in both tests and 44.7% in organic group with abnormal finding in both tests. In conclusion, AVS-penogram is a primary diagnostic method in screening impotent patients and type I is regarded as psychogenic impotence. In Type IIB and IIC, sub-classification of curve type is needed for differential diagnosis between psychogenic and organic impotence. (Abstract Truncated)

Sleep disturbance and neurocognitive function during the recovery from a sport-related concussion in adolescents.

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Kostyun, Regina O; Milewski, Matthew D; Hafeez, Imran

2015-03-01

Sleep disturbances are a hallmark sign after a sport-related concussion (SRC). Poor sleep has been shown to adversely affect baseline neurocognitive test scores, but it is not comprehensively understood how neurocognitive function is affected by disrupted sleep during recovery from a concussion. To identify the correlation between adolescent athletes' neurocognitive function and their self-reported sleep quantity and sleep disturbance symptoms during recovery from SRC. Cross-sectional study; Level of evidence, 3. Immediate Post-Concussion Assessment and Cognition Testing (ImPACT) data were retrospectively collected for 545 adolescent athletes treated for SRC at a sports medicine concussion clinic. Patients were stratified into groups based on 2 criteria: self-reported sleep duration and self-reported sleep disturbance symptoms during postinjury ImPACT testing. Sleep duration was classified as short (9 hours). Sleep disturbance symptoms were self-reported as part of the Post-Concussion Symptom Scale (PCSS) as either sleeping less than normal, sleeping more than normal, or having trouble falling asleep. One-way analyses of variance were conducted to examine the effects that sleep duration as well as self-reported sleep disturbance symptoms had on composite scores. A total of 1067 ImPACT tests were analyzed: test 1, 545; test 2, 380; and test 3, 142. Sleeping fewer than 7 hours the night before testing correlated with higher PCSS scores (P sleeping longer than 9 hours correlated with worse visual memory (P = .01), visual motor speed (P sleep disturbance symptoms, patients demonstrated worse composite scores during ImPACT testing when they self-reported sleeping more than normal (ImPACT test 1: verbal memory, P sleep had been disrupted. Adolescent patients who perceive that their sleep is somehow disrupted after SRC may report a greater number of concussion symptoms during their recovery. In addition, the study results suggest that sleeping more than normal may

Efficacy and complications of radiotherapy of anterior visual pathway tumors

International Nuclear Information System (INIS)

Capo, H.; Kupersmith, M.J.

1991-01-01

A progressive disturbance in visual acuity or visual field, along with an unexplained optic nerve atrophy, suggests the possibility of a tumor. Tumors that frequently affect the anterior visual pathway include primary optic nerve sheath meningiomas, intracranial meningiomas, optic gliomas, pituitary tumors, and craniopharyngiomas. The location of these tumors sometimes prohibits a complete surgical excision that might jeopardize the visual system. Radiation therapy, however, can be beneficial in these cases. This article reviews the indications for radiotherapy of tumors that involve the anterior visual pathway, along with the possible complications. Cases that present the effect of radiation therapy and radiation damage are presented.131 references

Neurologic complications of electrolyte disturbances and acid-base balance.

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Espay, Alberto J

2014-01-01

Electrolyte and acid-base disturbances are common occurrences in daily clinical practice. Although these abnormalities can be readily ascertained from routine laboratory findings, only specific clinical correlates may attest as to their significance. Among a wide phenotypic spectrum, acute electrolyte and acid-base disturbances may affect the peripheral nervous system as arreflexic weakness (hypermagnesemia, hyperkalemia, and hypophosphatemia), the central nervous system as epileptic encephalopathies (hypomagnesemia, dysnatremias, and hypocalcemia), or both as a mixture of encephalopathy and weakness or paresthesias (hypocalcemia, alkalosis). Disabling complications may develop not only when these derangements are overlooked and left untreated (e.g., visual loss from intracranial hypertension in respiratory or metabolic acidosis; quadriplegia with respiratory insufficiency in hypermagnesemia) but also when they are inappropriately managed (e.g., central pontine myelinolisis when rapidly correcting hyponatremia; cardiac arrhythmias when aggressively correcting hypo- or hyperkalemia). Therefore prompt identification of the specific neurometabolic syndromes is critical to correct the causative electrolyte or acid-base disturbances and prevent permanent central or peripheral nervous system injury. This chapter reviews the pathophysiology, clinical investigations, clinical phenotypes, and current management strategies in disorders resulting from alterations in the plasma concentration of sodium, potassium, calcium, magnesium, and phosphorus as well as from acidemia and alkalemia. © 2014 Elsevier B.V. All rights reserved.

Written accounts of living with psychogenic nonepileptic seizures: A thematic analysis.

Science.gov (United States)

Rawlings, Gregg H; Brown, Ian; Stone, Brendan; Reuber, Markus

2017-08-01

Qualitative studies examining lived experiences of psychogenic nonepileptic seizures (PNES) have predominantly relied on datasets collected using clinical or research interviews. This study pursued a different approach by investigating individuals' written accounts of their condition. Participants (n=19) were recruited from membership-led organisations for individuals living with seizures and from a United Kingdom hospital. Participants were instructed to produce four pieces of writing: 1) about their thoughts and feelings about their condition; 2) a letter to their condition; 3) a letter to their younger self; and 4) about a personal value. All writings were analysed using thematic analysis. Six main-themes emerged from the data. Theme 1: 'living with PNES' demonstrated that all participants presented the condition as having a debilitating effect. Theme 2: 'Emotions' revealed that individuals were struggling with anxiety, low mood and self-worth. Theme 3: 'Seizure symptoms' showed variability was a prominent feature in the description of ictal events. Theme 4: 'Treatment and outcomes' demonstrated that individual's perception of diagnosis and therapy differed greatly. Theme 5: 'Causation and development' revealed that the majority of participants spontaneously reported experiencing a traumatic event in the past. Theme 6: 'Lack of understanding' by themselves, the public and healthcare professionals appeared to pose considerable challenges to participants. Qualitative research has an important role to play for improving our understanding of PNES. The findings contribute to the literature by highlighting the nature of stigma that people with PNES experience, and also their proneness to demonstrate problems with self-worth. Copyright © 2017 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

Increased odds and predictive rates of MMPI-2-RF scale elevations in patients with psychogenic non-epileptic seizures and observed sex differences.

Science.gov (United States)

Del Bene, Victor A; Arce Rentería, Miguel; Maiman, Moshe; Slugh, Mitch; Gazzola, Deana M; Nadkarni, Siddhartha S; Barr, William B

2017-07-01

The Minnesota Multiphasic Personality Inventory-2-Restructured Form (MMPI-2-RF) is a self-report instrument, previously shown to differentiate patients with epileptic seizures (ES) and psychogenic non-epileptic seizures (PNES). At present, the odds of MMPI-2-RF scale elevations in PNES patients, as well as the diagnostic predictive value of such scale elevations, remain largely unexplored. This can be of clinical utility, particularly when a diagnosis is uncertain. After looking at mean group differences, we applied contingency table derived odds ratios to a sample of ES (n=92) and PNES (n=77) patients from a video EEG (vEEG) monitoring unit. We also looked at the positive and negative predictive values (PPV, NPV), as well as the false discovery rate (FDR) and false omission rate (FOR) for scales found to have increased odds of elevation in PNES patients. This was completed for the overall sample, as well as the sample stratified by sex. The odds of elevations related to somatic concerns, negative mood, and suicidal ideation in the PNES sample ranged from 2 to 5 times more likely. Female PNES patients had 3-6 times greater odds of such scale elevations, while male PNES patients had odds of 5-15 times more likely. PPV rates ranged from 53.66% to 84.62%, while NPV rates ranged from 47.52% to 90.91%. FDR across scales ranged from 15.38% to 50%, while the FOR ranged from 9.09% to 52.47%. Consistent with prior research, PNES patients have greater odds of MMPI-2-RF scale elevations, particularly related to somatic concerns and mood disturbance. Female PNES patients endorsed greater emotional distress, including endorsement of suicide related items. Elevations of these scales could aid in differentiating PNES from ES patients, although caution is warranted due to the possibility of both false positives and the incorrect omissions of PNES cases. Copyright © 2017 Elsevier Inc. All rights reserved.

Socialization characteristics in patients with psychogenic nonepileptic seizures (PNES).

Science.gov (United States)

Vaidya-Mathur, Urmi; Myers, Lorna; Laban-Grant, Olgica; Lancman, Marcelo; Lancman, Martin; Jones, Jace

2016-03-01

The purpose of this study was to describe social behaviors and preferences in adults with psychogenic nonepileptic seizures (PNES) including self-reported use of various socialization mediums (face-to-face and indirect communication) as well as perceived social barriers. One hundred forty-one consecutive patients with a diagnosis of PNES that was later confirmed through inpatient video-EEG monitoring were administered a questionnaire on the day of their first outpatient appointment. The questionnaire was designed to assess preferences in socialization practices, frequency of interpersonal contact, use of social media, and perceived barriers to socialization. The survey was developed to gain a better understanding of the socialization behaviors and preferences of our patients for the future development of customized activities in our wellness program. Contrary to prevalent assumptions that patients with PNES tend to be socially isolated, our responders reported that they were in fact quite socially connected (72.2% reported daily communication with friends and family via telephone, 68.54% saw relatives in person weekly, 65.28% saw friends weekly, and 51.2% reported using the computer daily to socialize). Facebook was the preferred online social media. Indoor/solitary activities were most common with 57.44% stating that they watch TV/read/use the computer. The primary barriers to socialization that respondents endorsed were driving prohibition and medication side effects. Respondents expressed the greatest interest in online support groups or educational programs (29.46%), office-based support groups (28.57%), and volunteering (23.21%). Although it has been speculated that social isolation is a significant problem for patients with PNES, considerable participation in social activities was reported. Characteristics of socialization practices may be more nuanced than first believed. When addressing therapeutic interventions with this group of patients in the future, it

Cerebral Activity Changes in Different Traditional Chinese Medicine Patterns of Psychogenic Erectile Dysfunction Patients

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Qi Liu

2015-01-01

Full Text Available Background. Pattern differentiation is the foundation of traditional Chinese medicine (TCM treatment for erectile dysfunction (ED. This study aims to investigate the differences in cerebral activity in ED patients with different TCM patterns. Methods. 27 psychogenic ED patients and 27 healthy subjects (HS were enrolled in this study. Each participant underwent an fMRI scan in resting state. The fractional amplitude of low-frequency fluctuation (fALFF was used to detect the brain activity changes in ED patients with different patterns. Results. Compared to HS, ED patients showed an increased cerebral activity in bilateral cerebellum, insula, globus pallidus, parahippocampal gyrus, orbitofrontal cortex (OFC, and middle cingulate cortex (MCC. Compared to the patients with liver-qi stagnation and spleen deficiency pattern (LSSDP, the patients with kidney-yang deficiency pattern (KDP showed an increased activity in bilateral brainstem, cerebellum, hippocampus, and the right insula, thalamus, MCC, and a decreased activity in bilateral putamen, medial frontal gyrus, temporal pole, and the right caudate nucleus, OFC, anterior cingulate cortex, and posterior cingulate cortex (P<0.005. Conclusions. The ED patients with different TCM patterns showed different brain activities. The differences in cerebral activity between LSSDP and KDP were mainly in the emotion-related regions, including prefrontal cortex and cingulated cortex.

Visual stimulation, {sup 1}H MR spectroscopy and fMRI of the human visual pathways

Energy Technology Data Exchange (ETDEWEB)

Boucard, Christine C.; Cornelissen, Frans W. [University of Groningen, Laboratory for Experimental Ophthalmology, Postbus 30001, Groningen (Netherlands); University of Groningen, BCN Neuro-imaging Center, Postbus 196, Groningen (Netherlands); Mostert, Jop P.; Keyser, Jacques De [University Hospital Groningen, Department of Neurology, Groningen (Netherlands); Oudkerk, Matthijs; Sijens, Paul E. [University Hospital Groningen, Department of Radiology, Groningen (Netherlands)

2005-01-01

The purpose was to assess changes in lactate content and other brain metabolites under visual stimulation in optical chiasm, optic radiations and occipital cortex using multiple voxel MR spectroscopy (MRS). {sup 1}H chemical shift imaging (CSI) examinations of transverse planes centered to include the above structures were performed in four subjects at an echo time of 135 ms. Functional MRI (fMRI) was used to confirm the presence of activity in the visual cortex during the visual stimulation. Spectral maps of optical chiasm were of poor quality due to field disturbances caused by nearby large blood vessels and/or eye movements. The optic radiations and the occipital lobe did not show any significant MR spectral change upon visual stimulation, i.e., the peak areas of inositol, choline, creatine, glutamate and N-acetylaspartate were not affected. Reproducible lactate signals were not observed. fMRI confirmed the presence of strong activations in stimulated visual cortex. Prolonged visual stimulation did not cause significant changes in MR spectra. Any signal observed near the 1.33 ppm resonance frequency of the lactate methyl-group was artifactual, originating from lipid signals from outside the volume of interest (VOI). Previous claims about changes in lactate levels in the visual cortex upon visual stimulation may have been based on such erroneous observations. (orig.)

Activation of lateral geniculate nucleus and primary visual cortex as detected by functional magnetic resonance imaging in normal subjects and in patients with visual disturbance

Energy Technology Data Exchange (ETDEWEB)

Miki, Atsushi [Niigata Univ. (Japan). Graduate School of Medical and Dental Sciences

2002-12-01

Functional magnetic resonance imaging (fMRI) during visual stimulation can detect regional cerebral blood flow changes that reflect neural activity in the lateral geniculate nucleus and primary visual cortex, which are major relay points in the human afferent visual system. FMRI has been used in the clinical evaluation of visual disorders such as homonymous hemianopia and unilateral eye diseases (optic neuritis, amblyopia, and so on). Future development in the data acquisition and data analysis may facilitate the use of fMRI for the management of patients with visual deficits and understanding of the visual disorders. (author)

Activation of lateral geniculate nucleus and primary visual cortex as detected by functional magnetic resonance imaging in normal subjects and in patients with visual disturbance

International Nuclear Information System (INIS)

Miki, Atsushi

2002-01-01

Functional magnetic resonance imaging (fMRI) during visual stimulation can detect regional cerebral blood flow changes that reflect neural activity in the lateral geniculate nucleus and primary visual cortex, which are major relay points in the human afferent visual system. FMRI has been used in the clinical evaluation of visual disorders such as homonymous hemianopia and unilateral eye diseases (optic neuritis, amblyopia, and so on). Future development in the data acquisition and data analysis may facilitate the use of fMRI for the management of patients with visual deficits and understanding of the visual disorders. (author)

Visual Hallucinations Due to Rivastigmine Transdermal Patch Application in Alzheimer's Disease; The First Case Report

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Yıldız Değirmenci

2016-12-01

Full Text Available Rivastigmine is a well-known dual acting acetylcholinesterase and butyrylcholinesterase inhibitor, which is effective on behavioral and psychiatric symptoms including hallucinations, as well as cognitive symptoms of dementia. The most common adverse effects of rivastigmine related to cholinergic stimulation in brain and peripheral tissues are gastrointestinal, cardiorespiratory, extrapyramidal, genitourinary, musculoskeletal symptoms, sleep disturbances, and skin irritations with the transdermal patch form in particular. Despite to the previous reports revealing the improving effects of the drug on hallucinations, we presented a-80 year old women with Alzheimer's disease suffering from visual hallucinations whose complaints began with rivastigmine treatment. Since the patient had recent memory disturbance without any behavioral and/or psychiatric symptoms before rivastigmine administration, and visual hallucinations disappeared with the discontinuation of the drug, visual hallucinations were attributed to rivastigmine.

Disturbance observer-based L1 robust tracking control for hypersonic vehicles with T-S disturbance modeling

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Yang Yi

2016-11-01

Full Text Available This article concerns a disturbance observer-based L1 robust anti-disturbance tracking algorithm for the longitudinal models of hypersonic flight vehicles with different kinds of unknown disturbances. On one hand, by applying T-S fuzzy models to represent those modeled disturbances, a disturbance observer relying on T-S disturbance models can be constructed to track the dynamics of exogenous disturbances. On the other hand, L1 index is introduced to analyze the attenuation performance of disturbance for those unmodeled disturbances. By utilizing the existing convex optimization algorithm, a disturbance observer-based proportional-integral-controlled input is proposed such that the stability of hypersonic flight vehicles can be ensured and the tracking error for velocity and altitude in hypersonic flight vehicle models can converge to equilibrium point. Furthermore, the satisfactory disturbance rejection and attenuation with L1 index can be obtained simultaneously. Simulation results on hypersonic flight vehicle models can reflect the feasibility and effectiveness of the proposed control algorithm.

[Symptoms and lesion localization in visual agnosia].

Science.gov (United States)

Suzuki, Kyoko

2004-11-01

There are two cortical visual processing streams, the ventral and dorsal stream. The ventral visual stream plays the major role in constructing our perceptual representation of the visual world and the objects within it. Disturbance of visual processing at any stage of the ventral stream could result in impairment of visual recognition. Thus we need systematic investigations to diagnose visual agnosia and its type. Two types of category-selective visual agnosia, prosopagnosia and landmark agnosia, are different from others in that patients could recognize a face as a face and buildings as buildings, but could not identify an individual person or building. Neuronal bases of prosopagnosia and landmark agnosia are distinct. Importance of the right fusiform gyrus for face recognition was confirmed by both clinical and neuroimaging studies. Landmark agnosia is related to lesions in the right parahippocampal gyrus. Enlarged lesions including both the right fusiform and parahippocampal gyri can result in prosopagnosia and landmark agnosia at the same time. Category non-selective visual agnosia is related to bilateral occipito-temporal lesions, which is in agreement with the results of neuroimaging studies that revealed activation of the bilateral occipito-temporal during object recognition tasks.

Perceptions of natural disturbance in Tatra National Park, Poland

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Švajda Juraj

2016-06-01

Full Text Available Since the last decades, natural disturbances in forests including protected areas have intensified. They have the potential to impact visual quality and safety of visitors as well as spread beyond protected area boundaries. While economic and ecological impacts are well studied, there is still a lack of work focused on human dimensions and social aspects. This study examines visitor perceptions towards bark beetle infestation in Tatra National Park, Poland. The findings, based on visitor surveys collected during the summer of 2014, indicate the significance of different factors influencing visitor attitudes towards the bark beetle. Age of visitors and importance of the bark beetle issue for them (based on subjective ratings of importance of bark beetle issue for respondents are the most prominent variables. Also place of origin and environmental worldview were recognized as significantly important variables in accordance with similar studies. Results suggest management implications for park authorities including public relations and environmental education in order to increase knowledge and support for natural disturbance and ecological integrity policies in the national park.

The pattern of complaints about Australian wind farms does not match the establishment and distribution of turbines: support for the psychogenic, 'communicated disease' hypothesis.

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Chapman, Simon; St George, Alexis; Waller, Karen; Cakic, Vince

2013-01-01

With often florid allegations about health problems arising from wind turbine exposure now widespread, nocebo effects potentially confound any future investigation of turbine health impact. Historical audits of health complaints are therefore important. We test 4 hypotheses relevant to psychogenic explanations of the variable timing and distribution of health and noise complaints about wind farms in Australia. All Australian wind farms (51 with 1634 turbines) operating 1993-2012. Records of complaints about noise or health from residents living near 51 Australian wind farms were obtained from all wind farm companies, and corroborated with complaints in submissions to 3 government public enquiries and news media records and court affidavits. These are expressed as proportions of estimated populations residing within 5 km of wind farms. There are large historical and geographical variations in wind farm complaints. 33/51 (64.7%) of Australian wind farms including 18/34 (52.9%) with turbine size >1 MW have never been subject to noise or health complaints. These 33 farms have an estimated 21,633 residents within 5 km and have operated complaint-free for a cumulative 267 years. Western Australia and Tasmania have seen no complaints. 129 individuals across Australia (1 in 254 residents) appear to have ever complained, with 94 (73%) being residents near 6 wind farms targeted by anti wind farm groups. The large majority 116/129(90%) of complainants made their first complaint after 2009 when anti wind farm groups began to add health concerns to their wider opposition. In the preceding years, health or noise complaints were rare despite large and small-turbine wind farms having operated for many years. The reported historical and geographical variations in complaints are consistent with psychogenic hypotheses that expressed health problems are "communicated diseases" with nocebo effects likely to play an important role in the aetiology of complaints.

MRI of optic tract lesions: Review and correlation with visual field defects

International Nuclear Information System (INIS)

Fadzli, F.; Ramli, N.; Ramli, N.M.

2013-01-01

Visual field defects are a conglomerate of patterns of visual impairment derived from diseases affecting the optic nerve as it extends from the globe to the visual cortex. They are complex signs requiring perimetry or visual confrontation for delineation and are associated with diverse aetiologies. This review considers the chiasmatic and post-chiasmatic causes of visual disturbances, with an emphasis on magnetic resonance imaging (MRI) techniques. Newer MRI sequences are considered, such as diffusion-tensor imaging. MRI images are correlated with perimetric findings in order to demonstrate localization of lesions in the visual pathway. This may serve as a valuable reference tool to clinicians and radiologists in the early diagnostic process of differentiating causes of various visual field defects in daily practice

Role of biomarkers in differentiating new-onset seizures from psychogenic nonepileptic seizures

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Mahendra Javali

2017-01-01

Full Text Available Introduction: Review of literature revealed very limited studies considering a combination of serum prolactin (PRL and serum creatine kinase (CK as markers for differentiating epileptic and psychogenic nonepileptic seizures (PNES. Therefore, in the present study, we analyzed the role of serum PRL and serum CK, individually and in combination. Methodology: This prospective study was conducted in a tertiary care medical teaching hospital over a period of 18 months. Patients aged over 15 years suspected to have new-onset seizures presenting within 5 h of ictus were included in this study. CK, serum PRL was measured at 0–1, 1–3, and 3–5 h after seizures. Results: Hundred subjects were studied for the role of serum PRL and serum CK in differentiating epileptic and PNES. The mean age was 42.24 years with a male:female ratio of 1.27:1. All patients of generalized tonic–clonic seizures (GTCS, who presented within 1 h, had elevated PRL, whereas 75% of patients with partial seizures had elevated PRL within 1 h of presentation. Nearly 91.66% of patients with GTCS who presented within 1 h had elevated CPK, whereas 70% of patients with partial seizures had elevated CPK. None of the patients diagnosed with PNES showed rise in either of the markers. Conclusion: In the present study, none of the patients with PNES showed raise in either serum PRL or CK. However, there was no correlation between the types of seizure and PRL or serum CK levels.

Disturbance rejection performance analyses of closed loop control systems by reference to disturbance ratio.

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Alagoz, Baris Baykant; Deniz, Furkan Nur; Keles, Cemal; Tan, Nusret

2015-03-01

This study investigates disturbance rejection capacity of closed loop control systems by means of reference to disturbance ratio (RDR). The RDR analysis calculates the ratio of reference signal energy to disturbance signal energy at the system output and provides a quantitative evaluation of disturbance rejection performance of control systems on the bases of communication channel limitations. Essentially, RDR provides a straightforward analytical method for the comparison and improvement of implicit disturbance rejection capacity of closed loop control systems. Theoretical analyses demonstrate us that RDR of the negative feedback closed loop control systems are determined by energy spectral density of controller transfer function. In this manner, authors derived design criteria for specifications of disturbance rejection performances of PID and fractional order PID (FOPID) controller structures. RDR spectra are calculated for investigation of frequency dependence of disturbance rejection capacity and spectral RDR analyses are carried out for PID and FOPID controllers. For the validation of theoretical results, simulation examples are presented. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

[Nursing Experience of Using Mirror Visual Feedback for a Schizophrenia Patient With Visual Hallucinations].

Science.gov (United States)

Lan, Shu-Ling; Chen, Yu-Chi; Chang, Hsiu-Ju

2018-06-01

The aim of this paper was to describe the nursing application of mirror visual feedback in a patient suffering from long-term visual hallucinations. The intervention period was from May 15th to October 19th, 2015. Using the five facets of psychiatric nursing assessment, several health problems were observed, including disturbed sensory perceptions (prominent visual hallucinations) and poor self-care (e.g. limited abilities to self-bathe and put on clothing). Furthermore, "caregiver role strain" due to the related intense care burden was noted. After building up a therapeutic interpersonal relationship, the technique of brain plasticity and mirror visual feedback were performed using multiple nursing care methods in order to help the patient suppress her visual hallucinations by enhancing a different visual stimulus. We also taught her how to cope with visual hallucinations in a proper manner. The frequency and content of visual hallucinations were recorded to evaluate the effects of management. The therapeutic plan was formulated together with the patient in order to boost her self-confidence, and a behavior contract was implemented in order to improve her personal hygiene. In addition, psychoeducation on disease-related topics was provided to the patient's family, and they were encouraged to attend relevant therapeutic activities. As a result, her family became less passive and negative and more engaged in and positive about her future. The crisis of "caregiver role strain" was successfully resolved. The current experience is hoped to serve as a model for enhancing communication and cooperation between family and staff in similar medical settings.

Geometric Hypergraph Learning for Visual Tracking

OpenAIRE

Du, Dawei; Qi, Honggang; Wen, Longyin; Tian, Qi; Huang, Qingming; Lyu, Siwei

2016-01-01

Graph based representation is widely used in visual tracking field by finding correct correspondences between target parts in consecutive frames. However, most graph based trackers consider pairwise geometric relations between local parts. They do not make full use of the target's intrinsic structure, thereby making the representation easily disturbed by errors in pairwise affinities when large deformation and occlusion occur. In this paper, we propose a geometric hypergraph learning based tr...

Mapping of forest disturbance magnitudes across the US National Forest System

Science.gov (United States)

Hernandez, A. J.; Healey, S. P.; Ramsey, R. D.; McGinty, C.; Garrard, C.; Lu, N.; Huang, C.

2013-12-01

A precise record in conjunction with ongoing monitoring of carbon pools constitutes essentials inputs for the continuous modernization of an ever- dynamic science such as climate change. This is particularly important in forested ecosystems for which accurate field archives are available and can be used in combination with historic satellite imagery to obtain spatially explicit estimates of several indicators that can be used in the assessment of said carbon pools. Many forest disturbance processes limit storage of carbon in forested ecosystems and thereby reduce those systems' capacity to mitigate changes in the global climate system. A component of the US National Forest System's (NFS) comprehensive plan for carbon monitoring includes accounting for mapped disturbances, such as fires, harvests, and insect activity. A long-term time series of maps that show the timing, extent, type, and magnitude of disturbances going back to 1990 has been prepared for the United States Forest Service (USFS) Northern Region, and is currently under preparation for the rest of the NFS regions covering more than 75 million hectares. Our mapping approach starts with an automated initial detection of annual disturbances using imagery captured within the growing season from the Landsat archive. Through a meticulous process, the initial detections are then visually inspected, manually corrected and labeled using various USFS ancillary datasets and Google Earth high-resolution historic imagery. We prepared multitemporal models of percent canopy cover and live tree carbon (T/ha) that were calibrated with extensive (in excess of 2000 locations) field data from the US Forest Service Forest Inventory and Analysis program (FIA). The models were then applied to all the years of the radiometrically corrected and normalized Landsat time series in order to provide annual spatially explicit estimates of the magnitude of change in terms of these two attributes. Our results provide objective, widely

Disturbance recording system

International Nuclear Information System (INIS)

Chandra, A.K.; Deshpande, S.V.; Mayya, A.; Vaidya, U.W.; Premraj, M.K.; Patil, N.B.

1994-01-01

A computerized system for disturbance monitoring, recording and display has been developed for use in nuclear power plants and is versatile enough to be used where ever a large number of parameters need to be recorded, e.g. conventional power plants, chemical industry etc. The Disturbance Recording System (DRS) has been designed to continuously monitor a process plant and record crucial parameters. The DRS provides a centralized facility to monitor and continuously record 64 process parameters scanned every 1 sec for 5 days. The system also provides facility for storage of 64 parameters scanned every 200 msec during 2 minutes prior to and 3 minutes after a disturbance. In addition the system can initiate, on demand, the recording of 8 parameters at a fast rate of every 5 msec for a period of 5 sec. and thus act as a visicorder. All this data is recorded in non-volatile memory and can be displayed, printed/plotted and used for subsequent analysis. Since data can be stored densely on floppy disks, the volume of space required for archival storage is also low. As a disturbance recorder, the DRS allows the operator to view the state of the plant prior to occurrence of the disturbance and helps in identifying the root cause. (author). 10 refs., 7 figs

Detecting Landscape Disturbance at the Nasca Lines Using SAR Data Collected from Airborne and Satellite Platforms

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Douglas C. Comer

2017-10-01

Full Text Available We used synthetic aperture radar (SAR data collected over Peru’s Lines and Geoglyphs of the Nasca and Palpa World Heritage Site to detect and measure landscape disturbance threatening world-renowned archaeological features and ecosystems. We employed algorithms to calculate correlations between pairs of SAR returns, collected at different times, and generate correlation images. Landscape disturbances even on the scale of pedestrian travel are discernible in correlation images generated from airborne, L-band SAR. Correlation images derived from C-band SAR data collected by the European Space Agency’s Sentinel-1 satellites also provide detailed landscape change information. Because the two Sentinel-1 satellites together have a repeat pass interval that can be as short as six days, products derived from their data can not only provide information on the location and degree of ground disturbance, but also identify a time window of about one to three weeks during which disturbance must have occurred. For Sentinel-1, this does not depend on collecting data in fine-beam modes, which generally sacrifice the size of the area covered for a higher spatial resolution. We also report on pixel value stretching for a visual analysis of SAR data, quantitative assessment of landscape disturbance, and statistical testing for significant landscape change.

Visual pathways involvement in children with acute viral encephalitis

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Voitenkov Vladislav Borisovich

2013-10-01

Full Text Available AIM: To investigate extent and nature of visual pathways involvement in children with acute viral encephalitis. METHODS: Thirty patients(age 5-12 yearswith acute viral encephalitis underwent visual evoked potentials(VEPinvestigation within 12 days from the appearance of the first signs of disease. Latency and amplitude of P100 peak were compared with normative data and between patients with varicella and tick-borne encephalitis. RESULTS: There were no significant differences between children with these two forms of encephalitis. In the whole group in 40% of the cases signs of the visual cortex dysfunction(P100 amplitude loweringand mild slowing of the conductivity along the visual pathways(P100 latency lengtheningwere seen. In 3% of the cases retrobulbar optic neuritis was diagnosed. CONCLUSION:The results indicate that visual pathway have good endurance to the viral encephalitis anatomically, but functionally visual cortex is quite vulnerable towards general disturbances caused by this kind of illness.

Long-term visual outcome after microsurgical removal of occipital lobe cavernomas.

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Kivelev, Juri; Koskela, Elina; Setälä, Kirsi; Niemelä, Mika; Hernesniemi, Juha

2012-08-01

Cavernomas in the occipital lobe are relatively rare. Because of the proximity to the visual cortex and incoming subcortical tracts, microsurgical removal of occipital cavernomas may be associated with a risk of visual field defects. The goal of the study was to analyze long-term outcome after operative treatment of occipital cavernomas with special emphasis on visual outcome. Of the 390 consecutive patients with cavernomas who were treated at Helsinki University Central Hospital between 1980 and 2011, 19 (5%) had occipital cavernomas. Sixteen patients (4%) were surgically treated and are included in this study. The median age was 39 years (range 3-59 years). Seven patients (56%) suffered from hemorrhage preoperatively, 5 (31%) presented with visual field deficits, 11 (69%) suffered from seizures, and 4 (25%) had multiple cavernomas. Surgery was indicated for progressive neurological deterioration. The median follow-up after surgery was 5.25 years (range 0.5-14 years). All patients underwent thorough neuroophthalmological assessment to determine visual outcome after surgery. Visual fields were classified as normal, mild homonymous visual field loss (not disturbing the patient, driving allowed), moderate homonymous visual field loss (disturbing the patient, driving prohibited), and severe visual field loss (total homonymous hemianopia or total homonymous quadrantanopia). At the last follow-up, 4 patients (25%) had normal visual fields, 6 (38%) had a mild visual field deficit, 1 (6%) complained of moderate visual field impairment, and 5 (31%) had severe homonymous visual field loss. Cavernomas seated deeper than 2 cm from the pial surface carried a 4.4-fold risk of postoperative visual field deficit relative to superficial ones (p = 0.034). Six (55%) of the 11 patients presenting with seizures were seizure-free postoperatively. Eleven (69%) of 16 patients had no disability during the long-term follow-up. Surgical removal of occipital cavernomas may carry a

Positron emission tomography in patients with psychogenic non-epileptic seizures

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McGonigal A

2016-04-01

Full Text Available Aileen McGonigal,1–3 Marie Arthuis,3 Jean-Arthur Micoulaud-Franchi,4,5 Fabrice Bartolomei,1–3 Eric Guedj6–8 1Institut de Neurosciences des Systèmes, INSERM UMR 1106, Marseille, France; 2Aix Marseille University, Faculty of Medicine, Marseille, France; 3Clinical Neurophysiology Department, Timone Hospital, Marseille, France; 4Department of Functional Investigation of the Nervous System, Sleep Clinic, Bordeaux University Hospital, Bordeaux, France; 5USR CNRS 3413, University of Bordeaux, France; 6Biophysics and Nuclear Medicine Department, Timone Hospital, Marseille, France; 7Aix-Marseille University, CERIMED, Marseille, France; 8Aix-Marseille University, CNRS, UMR7289, INT, Marseille, FranceWe have read with interest the recent review entitled “Uncovering the etiology of conversion disorder: insights from functional neuroimaging” by Maryam Ejareh dar and Richard AA Kanaan,1 published in Neuropsychiatric Disease and Treatment. Our paper on resting state brain metabolism measured by positron emission tomography (PET was included and discussed.2 We were most surprised to see that the authors of the review seem to have misunderstood the findings of our study, which concerned patients with psychogenic non-epileptic seizures (PNES. The authors state that the 16 patients included in our study “were later found to have PNES with comorbid epilepsy”. This is incorrect, since our study included only patients with PNES in whom comorbid epilepsy was excluded. This crucial point is indeed detailed in the Methods section of our article and clearly stated in the abstract: “in all patients, the diagnosis was subsequently confirmed to be PNES with no coexisting epilepsy.” It is thus on the basis of incorrect understanding of our results that Drs Ejareh dar and Kanaan discuss the possible significance of hypometabolism in the anterior cingulate region described in our paper, and erroneously suggest that interpretation of PET findings is

Patients' and neurologists' perception of epilepsy and psychogenic nonepileptic seizures.

Science.gov (United States)

Whitehead, Kimberley; Kandler, Rosalind; Reuber, Markus

2013-04-01

Although differences in illness perceptions between neurologists and patients with epilepsy or psychogenic nonepileptic seizures (PNES) are likely to be clinically relevant, this is the first study to attempt a direct comparison. In addition, this study compares the illness perceptions of patients with epilepsy with those of patients with PNES. Thirty-four patients with epilepsy, 40 patients with PNES, and 45 neurologists were recruited. All patient participants completed versions of the illness perception questionnaire revised (IPQ-R) adapted for epileptic or nonepileptic seizure disorders, single-item symptom attribution question (SAQ), Hospital Anxiety and Depression Scale (HADS), Quality of Life in Epilepsy-31 (QOLIE-31), and Liverpool Seizure Severity Scale (LSSS). Participating neurologists completed two versions of the IPQ-R and two SAQs for epileptic and nonepileptic seizure disorders. Differences in illness perceptions between patients with epilepsy and patients with PNES were minor compared to those between patients with either seizure disorder and neurologists. Neurologists considered both seizure disorders more treatable and more amenable to personal control than did the patients themselves. Neurologists had much more polarized views of the etiology of both conditions; whereas patients mostly considered the causes of their seizure disorders as partially "physical" and partially "psychological," neurologists perceived epilepsy as an essentially "physical" and PNES as a clearly "psychological" problem. There are considerable differences between the illness perceptions of patients with seizure disorders and their doctors, which could represent barriers to successful clinical management. In particular, a discrepancy between neurologists' and patients' beliefs about the personal control that patients may be able to exert over PNES could contribute to the confusion or anger some patients report after the diagnosis has been explained to them. Furthermore

Defining Disturbance for Microbial Ecology.

Science.gov (United States)

Plante, Craig J

2017-08-01

Disturbance can profoundly modify the structure of natural communities. However, microbial ecologists' concept of "disturbance" has often deviated from conventional practice. Definitions (or implicit usage) have frequently included climate change and other forms of chronic environmental stress, which contradict the macrobiologist's notion of disturbance as a discrete event that removes biomass. Physical constraints and disparate biological characteristics were compared to ask whether disturbances fundamentally differ in microbial and macroorganismal communities. A definition of "disturbance" for microbial ecologists is proposed that distinguishes from "stress" and other competing terms, and that is in accord with definitions accepted by plant and animal ecologists.

Visual dysfunction, neurodegenerative diseases, and aging.

Science.gov (United States)

Jackson, Gregory R; Owsley, Cynthia

2003-08-01

The four most common sight-threatening conditions in older adults in North America are cataract, ARM, glaucoma, and diabetic retinopathy. Even in their moderate stages, these conditions cause visual sensory impairments and reductions in health-related quality of life, including difficulties in daily tasks and psychosocial problems. Many older adults are free from these conditions, yet still experience a variety of visual perceptual problems resulting from aging-related changes in the optics of the eye and degeneration of the visual neural pathways. These problems consist of impairments in visual acuity, contrast sensitivity, color discrimination, temporal sensitivity, motion perception, peripheral visual field sensitivity, and visual processing speed. PD causes a progressive loss of dopaminergic cells predominantly in the retina and possibly in other areas of the visual system. This retinal dopamine deficiency produces selective spatial-temporal abnormalities in retinal ganglion cell function, probably arising from altered receptive field organization in the PD retina. The cortical degeneration characteristics of AD, including neurofibrillary tangles and neuritic plaques, also are present in the visual cortical areas, especially in the visual association areas. The most prominent electrophysiologic change in AD is a delay in the P2 component of the flash VEP. Deficits in higher-order visual abilities typically are compromised in AD, including problems with visual attention, perceiving structure from motion, visual memory, visual learning, reading, and object and face perception. There have been reports of a visual variant of AD in which these types of visual problems are the initial and most prominent signs of the disease. Visual sensory impairments (e.g., contrast sensitivity or achromatopsia) also have been reported but are believed more reflective of cortical disturbances than of AD-associated optic neuropathy.

The Effectiveness of Simulator Motion in the Transfer of Performance on a Tracking Task Is Influenced by Vision and Motion Disturbance Cues.

Science.gov (United States)

Grundy, John G; Nazar, Stefan; O'Malley, Shannon; Mohrenshildt, Martin V; Shedden, Judith M

2016-06-01

To examine the importance of platform motion to the transfer of performance in motion simulators. The importance of platform motion in simulators for pilot training is strongly debated. We hypothesized that the type of motion (e.g., disturbance) contributes significantly to performance differences. Participants used a joystick to perform a target tracking task in a pod on top of a MOOG Stewart motion platform. Five conditions compared training without motion, with correlated motion, with disturbance motion, with disturbance motion isolated to the visual display, and with both correlated and disturbance motion. The test condition involved the full motion model with both correlated and disturbance motion. We analyzed speed and accuracy across training and test as well as strategic differences in joystick control. Training with disturbance cues produced critical behavioral differences compared to training without disturbance; motion itself was less important. Incorporation of disturbance cues is a potentially important source of variance between studies that do or do not show a benefit of motion platforms in the transfer of performance in simulators. Potential applications of this research include the assessment of the importance of motion platforms in flight simulators, with a focus on the efficacy of incorporating disturbance cues during training. © 2016, Human Factors and Ergonomics Society.

Disturbing, Disordered or Disturbed? Perspectives on the Definition of Problem Behavior in Educational Settings.

Science.gov (United States)

Wood, Frank H., Ed.; Lakin, K. Charlie, Ed.

The book contains five papers presented at a 1979 topical conference on the definition of emotional disturbance and behavioral disorders in educational settings. The first paper, by F. Wood, is titled "Defining Disturbing, Disordered, and Disturbed Behavior." Topics covered include ambivalence about defining deviant behavior by special educators,…

On disturbed time continuity in schizophrenia: an elementary impairment in visual perception?

Directory of Open Access Journals (Sweden)

Anne eGiersch

2013-05-01

Full Text Available Schizophrenia is associated with a series of visual perception impairments, which might impact on the patients’ every day life and be related to clinical symptoms. However, the heterogeneity of the visual disorders make it a challenge to understand both the mechanisms and the consequences of these impairments, i.e. the way patients experience the outer world. Based on earlier psychiatry literature, we argue that issues regarding time might shed a new light on the disorders observed in patients with schizophrenia. We will briefly review the mechanisms involved in the sense of time continuity and clinical evidence that they are impaired in patients with schizophrenia. We will then summarize a recent experimental approach regarding the coding of time-event structure in time, namely the ability to discriminate between simultaneous and asynchronous events. The use of an original method of analysis allowed us to distinguish between explicit and implicit judgements of synchrony. We showed that for SOAs below 20 ms neither patients nor controls fuse events in time. On the contrary subjects distinguish events at an implicit level even when judging them as synchronous. In addition, the implicit responses of patients and controls differ qualitatively. It is as if controls always put more weight on the last occurred event, whereas patients have a difficulty to follow events in time at an implicit level. In patients, there is a clear dissociation between results at short and large asynchronies, that suggest selective mechanisms for the implicit coding of time-event structure. These results might explain the disruption of the sense of time continuity in patients. We argue that this line of research might also help us to better understand the mechanisms of the visual impairments in patients and how they see their environment.

Sleep Disturbances in Neurodevelopmental Disorders.

Science.gov (United States)

Robinson-Shelton, Althea; Malow, Beth A

2016-01-01

Sleep disturbances are extremely prevalent in children with neurodevelopmental disorders compared to typically developing children. The diagnostic criteria for many neurodevelopmental disorders include sleep disturbances. Sleep disturbance in this population is often multifactorial and caused by the interplay of genetic, neurobiological and environmental overlap. These disturbances often present either as insomnia or hypersomnia. Different sleep disorders present with these complaints and based on the clinical history and findings from diagnostic tests, an appropriate diagnosis can be made. This review aims to provide an overview of causes, diagnosis, and treatment of sleep disturbances in neurodevelopmental disorders that present primarily with symptoms of hypersomnia and/or insomnia.

Phantom eye syndrome: types of visual hallucinations and related phenomena

DEFF Research Database (Denmark)

Roed Rasmussen, Marie Louise; Prause, Jan U; Johnson, Martin

2009-01-01

most often white or colored light, as a continuous sharp light or as moving dots. The most frequent triggers were darkness, closing of the eyes, fatigue, and psychological stress; 54% of patients had the experience more than once a week. Ten patients were so visually disturbed that it interfered...

Diagnosing psychogenic nonepileptic seizures: Video-EEG monitoring, suggestive seizure induction and diagnostic certainty.

Science.gov (United States)

Popkirov, Stoyan; Jungilligens, Johannes; Grönheit, Wenke; Wellmer, Jörg

2017-08-01

Psychogenic nonepileptic seizures (PNES) can remain undiagnosed for many years, leading to unnecessary medication and delayed treatment. A recent report by the International League Against Epilepsy Nonepileptic Seizures Task Force recommends a staged approach to the diagnosis of PNES (LaFrance, et al., 2013). We aimed to investigate its practical utility, and to apply the proposed classification to evaluate the role of long-term video-EEG monitoring (VEEG) and suggestive seizure induction (SSI) in PNES workup. Using electronic medical records, 122 inpatients (mean age 36.0±12.9years; 68% women) who received the diagnosis of PNES at our epilepsy center during a 4.3-year time period were included. There was an 82.8% agreement between diagnostic certainty documented at discharge and that assigned retroactively using the Task Force recommendations. In a minority of cases, having used the Task Force criteria could have encouraged the clinicians to give more certain diagnoses, exemplifying the Task Force report's utility. Both VEEG and SSI were effective at supporting high level diagnostic certainty. Interestingly, about one in four patients (26.2%) had a non-diagnostic ("negative") VEEG but a positive SSI. On average, this subgroup did not have significantly shorter mean VEEG recording times than VEEG-positive patients. However, VEEG-negative/SSI-positive patients had a significantly lower habitual seizure frequency than their counterparts. This finding emphasizes the utility of SSI in ascertaining the diagnosis of PNES in patients who do not have a spontaneous habitual event during VEEG due to, for example, low seizure frequency. Copyright © 2017 Elsevier Inc. All rights reserved.

The intermediate disturbance hypothesis applies to tropical forests, but disturbance contributes little to tree diversity.

Science.gov (United States)

Bongers, Frans; Poorter, Lourens; Hawthorne, William D; Sheil, Douglas

2009-08-01

The intermediate disturbance hypothesis (IDH) predicts local species diversity to be maximal at an intermediate level of disturbance. Developed to explain species maintenance and diversity patterns in species-rich ecosystems such as tropical forests, tests of IDH in tropical forest remain scarce, small-scale and contentious. We use an unprecedented large-scale dataset (2504 one-hectare plots and 331,567 trees) to examine whether IDH explains tree diversity variation within wet, moist and dry tropical forests, and we analyse the underlying mechanism by determining responses within functional species groups. We find that disturbance explains more variation in diversity of dry than wet tropical forests. Pioneer species numbers increase with disturbance, shade-tolerant species decrease and intermediate species are indifferent. While diversity indeed peaks at intermediate disturbance levels little variation is explained outside dry forests, and disturbance is less important for species richness patterns in wet tropical rain forests than previously thought.

[Objective assessment of disorders of visual perception following unilateral vestibular loss. Studies of the so-called Dandy symptom].

Science.gov (United States)

Stoll, W; Werner, F; Kauffmann, G

1991-02-01

Visual ability and compensatory eye movements during defined vertical oscillation were investigated in 20 patients with unilateral lesions of labyrinthine function and in 20 normal subjects. Oscillation frequencies were performed at the rate of 1 to 1.5 Hz with an amplitude of 5 cm, comparative to head locomotions of a running person. In synchronism with this, the visual function was tested with Landolt rings. Patients complaining of subjective visual disturbance during walking and running, also presented a measurable blur of vision under test conditions. In addition, eye movements were recorded and classified into three types. However, these eye movements showed no relation to gaze function. Our results suggest that the otolith-ocular reflex may participate in adjusting the vertical eye position during vertical stimulations at low frequencies. The effect of visual disturbances in patients with labyrinthine lesions is explained by the "efference-copy" initially described by von Holst. The efference-copy is responsible for the neutralisation of provoked retinal perceptions.

Intertidal soft-sediment community does not respond to disturbance as postulated by the intermediate disturbance hypothesis

Science.gov (United States)

Gerwing, Travis G.; Allen Gerwing, Alyssa M.; Macdonald, Tara; Cox, Kieran; Juanes, Francis; Dudas, Sarah E.

2017-11-01

The Intermediate Disturbance Hypothesis (IDH) predicts that disturbances of an intermediate frequency or intensity will maximize community biodiversity/richness. Once almost universally accepted, controversy now surrounds this hypothesis, and there have even been calls for its abandonment. Therefore, we experimentally evaluated if an infaunal community along the north coast of British Columbia, Canada, would respond to disturbances as predicted by the IDH. The characteristics of this soft-sediment intertidal mudflat (productivity, species pool, population growth rate) maximized our chances of finding evidence to support the IDH. More specifically, we tested if intermediate severities and frequencies of disturbance maximized infaunal community richness by mechanically disturbing sediment, and varying the intensity (0%, 25%, 50%, 75%, and 100% of the surface area of a plot disturbed) and frequency of sediment disturbance (never, once, twice, and every week during a four week period). No effect of frequency or intensity of sediment disturbance on community richness was observed. Further, none of our experimental treatments were statistically different than the controls. This is likely due to the subtle difference between successional stages in this soft-sediment habitat (difference of less than one taxa between treatments). Therefore, in habitats whose productivity, regional species pool, and population growth rates would otherwise suggest a response to disturbances as predicted by the IDH, minor differences between successional stages may result in richness patterns that deviate from those predicted by the IDH.

Climate change and forest disturbances

Science.gov (United States)

Virginia H. Dale; Linda A. Joyce; Steve McNulty; Ronald P. Neilson; Matthew P. Ayres; Michael D. Flannigan; Paul J. Hanson; Lloyd C. Irland; Ariel E. Lugo; Chris J. Peterson; Daniel Simberloff; Frederick J. Swanson; Brian J. Stocks; Michael Wotton

2001-01-01

This article examines how eight disturbances influence forest structure, composition, and function, and how climate change may influence the severity, frequency, and magnitude of disturbances to forests. We focus on examples from the United States, although these influences occur worldwide. We also consider options for coping with disturbance under changing climate....

MULTIDISCIPLINARY APPROACH TO THE CORRECTION OF ACCOMMODATION REFRACTION DISORDERS IN VISUALLY INTENSIVE LABOR PERSONS

Directory of Open Access Journals (Sweden)

I. G. Ovechkin

2015-01-01

Full Text Available Increased load on the visual analyzer of an operator, increase in everyday visual performance, universal introduction of information displaying on cathode-ray tubes result in temporary and stable visual disturbances. Accommodative refractive apparatus of an eye is one of the key points of application of visually intensive labor. Work associated with permanent eyestrain overloads oculomotor and accommodative apparatus thus provoking myopic shift, increase in dynamic refraction, exophoric or esophoric shift of initial visual equilibrium. Accommodation disorders are accompanied by changes in ciliary muscle blood supply, abnormalities of vegetative segment regulation, parasympathetic brain vascular dystonia due to the decreased tonus of sympathetic nervous system. Evaluation of certain kind of activity in terms of ergonomics includes examination of visual status and visual working capacity, development of visual professiograms and vision standards for certain professions, justification of methods and tools of visual work optimization. Visual disturbances in operators developing in the course of visually intensive occupational work should be considered from the viewpoint of traditional accommodation and refraction disorders as well as functional manifestations of general fatigue or thoracic cervical spine dysfunction. Symptoms of accommodative asthenopia can be regarded as a functional manifestation of general fatigue syndrome or functional neurosis. Development of multidisciplinary approach to the correction of accommodation refraction disorders in visually intensive labor persons is of scientific urgency and practical reasonability. There is a long-felt need in additional attraction of different specialists who use in their work physical factors for accommodative asthenopia correction. Development of multidisciplinary approach to accommodation refraction disorder correction in visually intensive labor persons is based on syndromic pathogenic

Body representation disturbances in visual perception and affordance perception persist in eating disorder patients after completing treatment

NARCIS (Netherlands)

Engel, Manja M; Keizer, Anouk

2017-01-01

Body image disturbances (BID) are a key feature of eating disorders (ED). Clinical experience shows that BID exists in patients who Completed their Eating Disorder Treatment (CEDT), however studies concerning BID in CEDT patients are often limited to cognition and affect, measured by interviews and

Visual and non-visual motion information processing during pursuit eye tracking in schizophrenia and bipolar disorder.

Science.gov (United States)

Trillenberg, Peter; Sprenger, Andreas; Talamo, Silke; Herold, Kirsten; Helmchen, Christoph; Verleger, Rolf; Lencer, Rebekka

2017-04-01

Despite many reports on visual processing deficits in psychotic disorders, studies are needed on the integration of visual and non-visual components of eye movement control to improve the understanding of sensorimotor information processing in these disorders. Non-visual inputs to eye movement control include prediction of future target velocity from extrapolation of past visual target movement and anticipation of future target movements. It is unclear whether non-visual input is impaired in patients with schizophrenia. We recorded smooth pursuit eye movements in 21 patients with schizophrenia spectrum disorder, 22 patients with bipolar disorder, and 24 controls. In a foveo-fugal ramp task, the target was either continuously visible or was blanked during movement. We determined peak gain (measuring overall performance), initial eye acceleration (measuring visually driven pursuit), deceleration after target extinction (measuring prediction), eye velocity drifts before onset of target visibility (measuring anticipation), and residual gain during blanking intervals (measuring anticipation and prediction). In both patient groups, initial eye acceleration was decreased and the ability to adjust eye acceleration to increasing target acceleration was impaired. In contrast, neither deceleration nor eye drift velocity was reduced in patients, implying unimpaired non-visual contributions to pursuit drive. Disturbances of eye movement control in psychotic disorders appear to be a consequence of deficits in sensorimotor transformation rather than a pure failure in adding cognitive contributions to pursuit drive in higher-order cortical circuits. More generally, this deficit might reflect a fundamental imbalance between processing external input and acting according to internal preferences.

Dissociative Disturbance in Hangul-Hanja Reading after a Left Posterior Occipital Lesion

Directory of Open Access Journals (Sweden)

Key-Chung Park

2008-01-01

Full Text Available Since the Korean language has two distinct writing systems, phonogram (Hangul and ideogram (Hanja: Chinese characters, alexia can present with dissociative disturbances in reading between the two systems. A 74-year-old right-handed man presented with a prominent reading impairment in Hangul with agraphia of both Hangul and Hanja after a left posterior occipital- parietal lesion. He could not recognize single syllable words and nonwords in Hangul, and visual errors were predominant in both Hanja reading and the Korean Boston Naming Test. In addition, he had difficulties in visuoperceptual tests including Judgment of Line Orientation, Hierarchical Navon figures, and complex picture scanning. These findings are consistent with the hypothesis that Hangul reading impairment results from a general visual perceptual deficit. However, this assumption cannot explain why performance on visually complex Hanja was better than performance on visually simple Hanja in our patient. In addition, the patient did not demonstrate higher accuracy on Hanja characters with fewer strokes than on words with more strokes. Thus, we speculate that the left posterior occipital area may be specialized for Hangul letter identification in this patient. This case demonstrates that Hangul-Hanja reading dissociation impairment can occur after occipital-parietal lesions.

Analysis of disturbance

International Nuclear Information System (INIS)

Ciala-Wein, H.; Stegmaier, W.

1977-12-01

The analyses of disturbances are the supposition for the development of processes and plants. They are very important in the field of nuclear testing plants. In this report are described the possibilities to register the circumstances of the disturbance in a pilot waste processing facility and a computer programme to interpret them. This is a first scheme and it will be necessary to complete it. (orig.) [de

Disturbance of a rare seabird by ship-based tourism in a marine protected area

Science.gov (United States)

Marcella, Timothy K.; Gende, Scott M.; Roby, Daniel D.; Allignol, Arthur

2017-01-01

Managers of marine protected areas (MPAs) must often seek ways to allow for visitation while minimizing impacts to the resources they are intended to protect. Using shipboard observers, we quantified the “zone of disturbance” for Kittlitz’s and marbled murrelets (Brachyramphus brevirostris and B. marmoratus) exposed to large cruise ships traveling through Glacier Bay National Park, one of the largest MPAs in North America. In the upper reaches of Glacier Bay, where Kittlitz’s murrelets predominated, binary logistic regression models predicted that 61% of all murrelets within 850 m perpendicular distance of a cruise ship were disturbed (defined as flushing or diving), whereas in the lower reaches, where marbled murrelets predominated, this percentage increased to 72%. Using survival analysis, murrelets in both reaches were found to react at greater distances when ships approached indirectly, presumably because of the ship’s larger profile, suggesting murrelets responded to visual rather than audio cues. No management-relevant covariates (e.g., ship velocity, route distance from shore) were found to be important predictors of disturbance, as distance from ship to murrelet accounted for > 90% of the explained variation in murrelet response. Utilizing previously published murrelet density estimates from Glacier Bay, and applying an average empirical disturbance probability (68%) out to 850 m from a cruise ship’s typical route, we estimated that a minimum of 9.8–19.6% of all murrelets in Glacier Bay are disturbed per ship entry. Whether these disturbance levels are inconsistent with Park management objectives, which include conserving wildlife as well as providing opportunities for visitation, depends in large part on whether disturbance events caused by cruise ships have impacts on murrelet fitness, which remains uncertain.

Disturbed prepulse inhibition in patients with schizophrenia is consequential to dysfunction of selective attention.

Science.gov (United States)

Scholes, Kirsty E; Martin-Iverson, Mathew T

2010-03-01

Controversy exists as to the cause of disturbed prepulse inhibition (PPI) in patients with schizophrenia. This study aimed to clarify the nature of PPI in schizophrenia using improved methodology. Startle and PPI were measured in 44 patients with schizophrenia and 32 controls across a range of startling stimulus intensities under two conditions, one while participants were attending to the auditory stimuli (ATTEND condition) and one while participants completed a visual task in order to ensure they were ignoring the auditory stimuli (IGNORE condition). Patients showed reduced PPI of R(MAX) (reflex capacity) and increased PPI of Hillslope (reflex efficacy) only under the INGORE condition, and failed to show the same pattern of attentional modulation of the reflex parameters as controls. In conclusion, disturbed PPI in schizophrenia appears to result from deficits in selective attention, rather than from preattentive dysfunction.

Motion of the two-control airplane in rectilinear flight after initial disturbances with introduction of controls following an exponential law

Science.gov (United States)

Klemin, Alexander

1937-01-01

An airplane in steady rectilinear flight was assumed to experience an initial disturbance in rolling or yawing velocity. The equations of motion were solved to see if it was possible to hasten recovery of a stable airplane or to secure recovery of an unstable airplane by the application of a single lateral control following an exponential law. The sample computations indicate that, for initial disturbances complex in character, it would be difficult to secure correlation with any type of exponential control. The possibility is visualized that the two-control operation may seriously impair the ability to hasten recovery or counteract instability.

ENHANCED NITROGEN IN MORPHOLOGICALLY DISTURBED BLUE COMPACT GALAXIES AT 0.20 < z < 0.35: PROBING GALAXY MERGING FEATURES

Energy Technology Data Exchange (ETDEWEB)

Chung, Jiwon; Rey, Soo-Chang; Yeom, Bum-Suk; Yi, Wonhyeong [Department of Astronomy and Space Science, Chungnam National University, Daejeon 305-764 (Korea, Republic of); Sung, Eon-Chang; Kyeong, Jaemann [Korea Astronomy and Space Science Institute, Daejeon 305-348 (Korea, Republic of); Humphrey, Andrew, E-mail: jiwon@cnu.ac.kr, E-mail: screy@cnu.ac.kr [Centro de Astrofisica da Universidade do Porto, Rua das Estrelas, 4150-762, Porto (Portugal)

2013-04-10

We present a study of correlations between the elemental abundances and galaxy morphologies of 91 blue compact galaxies (BCGs) at z = 0.20-0.35 with Sloan Digital Sky Survey (SDSS) DR7 data. We classify the morphologies of the galaxies as either ''disturbed'' or ''undisturbed'' by visual inspection of the SDSS images, and using the Gini coefficient and M{sub 20}. We derive oxygen and nitrogen abundances using the T{sub e} method. We find that a substantial fraction of BCGs with disturbed morphologies, indicative of merger remnants, show relatively high N/O and low O/H abundance ratios. The majority of the disturbed BCGs exhibit higher N/O values at a given O/H value compared to the morphologically undisturbed galaxies, implying more efficient nitrogen enrichment in disturbed BCGs. We detect Wolf-Rayet (WR) features in only a handful of the disturbed BCGs, which appears to contradict the idea that WR stars are responsible for high nitrogen abundance. Combining these results with Galaxy Evolution Explorer GR6 ultraviolet (UV) data, we find that the majority of the disturbed BCGs show systematically lower values of the H{alpha} to near-UV star formation rate ratio. The equivalent width of the H{beta} emission line is also systematically lower in the disturbed BCGs. Based on these results, we infer that disturbed BCGs have undergone star formation over relatively longer timescales, resulting in a more continuous enrichment of nitrogen. We suggest that this correlation between morphology and chemical abundances in BCGs is due to a difference in their recent star formation histories.

Image-Based Visual Servoing for Robotic Systems: A Nonlinear Lyapunov-Based Control Approach

International Nuclear Information System (INIS)

Dixon, Warren

2004-01-01

There is significant motivation to provide robotic systems with improved autonomy as a means to significantly accelerate deactivation and decommissioning (DandD) operations while also reducing the associated costs, removing human operators from hazardous environments, and reducing the required burden and skill of human operators. To achieve improved autonomy, this project focused on the basic science challenges leading to the development of visual servo controllers. The challenge in developing these controllers is that a camera provides 2-dimensional image information about the 3-dimensional Euclidean-space through a perspective (range dependent) projection that can be corrupted by uncertainty in the camera calibration matrix and by disturbances such as nonlinear radial distortion. Disturbances in this relationship (i.e., corruption in the sensor information) propagate erroneous information to the feedback controller of the robot, leading to potentially unpredictable task execution. This research project focused on the development of a visual servo control methodology that targets compensating for disturbances in the camera model (i.e., camera calibration and the recovery of range information) as a means to achieve predictable response by the robotic system operating in unstructured environments. The fundamental idea is to use nonlinear Lyapunov-based techniques along with photogrammetry methods to overcome the complex control issues and alleviate many of the restrictive assumptions that impact current robotic applications. The outcome of this control methodology is a plug-and-play visual servoing control module that can be utilized in conjunction with current technology such as feature recognition and extraction to enable robotic systems with the capabilities of increased accuracy, autonomy, and robustness, with a larger field of view (and hence a larger workspace). The developed methodology has been reported in numerous peer-reviewed publications and the

Automated attribution of remotely-sensed ecological disturbances using spatial and temporal characteristics of common disturbance classes.

Science.gov (United States)

Cooper, L. A.; Ballantyne, A.

2017-12-01

Forest disturbances are critical components of ecosystems. Knowledge of their prevalence and impacts is necessary to accurately describe forest health and ecosystem services through time. While there are currently several methods available to identify and describe forest disturbances, especially those which occur in North America, the process remains inefficient and inaccessible in many parts of the world. Here, we introduce a preliminary approach to streamline and automate both the detection and attribution of forest disturbances. We use a combination of the Breaks for Additive Season and Trend (BFAST) detection algorithm to detect disturbances in combination with supervised and unsupervised classification algorithms to attribute the detections to disturbance classes. Both spatial and temporal disturbance characteristics are derived and utilized for the goal of automating the disturbance attribution process. The resulting preliminary algorithm is applied to up-scaled (100m) Landsat data for several different ecosystems in North America, with varying success. Our results indicate that supervised classification is more reliable than unsupervised classification, but that limited training data are required for a region. Future work will improve the algorithm through refining and validating at sites within North America before applying this approach globally.

Sleep Disturbances in Mood Disorders.

Science.gov (United States)

Rumble, Meredith E; White, Kaitlin Hanley; Benca, Ruth M

2015-12-01

The article provides an overview of common and differentiating self-reported and objective sleep disturbances seen in mood-disordered populations. The importance of considering sleep disturbances in the context of mood disorders is emphasized, because a large body of evidence supports the notion that sleep disturbances are a risk factor for onset, exacerbation, and relapse of mood disorders. In addition, potential mechanisms for sleep disturbance in depression, other primary sleep disorders that often occur with mood disorders, effects of antidepressant and mood-stabilizing drugs on sleep, and the adjunctive effect of treating sleep in patients with mood disorders are discussed. Copyright © 2015 Elsevier Inc. All rights reserved.

The Pattern of Complaints about Australian Wind Farms Does Not Match the Establishment and Distribution of Turbines: Support for the Psychogenic, ‘Communicated Disease’ Hypothesis

Science.gov (United States)

Chapman, Simon; St. George, Alexis; Waller, Karen; Cakic, Vince

2013-01-01

Background and Objectives With often florid allegations about health problems arising from wind turbine exposure now widespread, nocebo effects potentially confound any future investigation of turbine health impact. Historical audits of health complaints are therefore important. We test 4 hypotheses relevant to psychogenic explanations of the variable timing and distribution of health and noise complaints about wind farms in Australia. Setting All Australian wind farms (51 with 1634 turbines) operating 1993–2012. Methods Records of complaints about noise or health from residents living near 51 Australian wind farms were obtained from all wind farm companies, and corroborated with complaints in submissions to 3 government public enquiries and news media records and court affidavits. These are expressed as proportions of estimated populations residing within 5 km of wind farms. Results There are large historical and geographical variations in wind farm complaints. 33/51 (64.7%) of Australian wind farms including 18/34 (52.9%) with turbine size >1 MW have never been subject to noise or health complaints. These 33 farms have an estimated 21,633 residents within 5 km and have operated complaint-free for a cumulative 267 years. Western Australia and Tasmania have seen no complaints. 129 individuals across Australia (1 in 254 residents) appear to have ever complained, with 94 (73%) being residents near 6 wind farms targeted by anti wind farm groups. The large majority 116/129(90%) of complainants made their first complaint after 2009 when anti wind farm groups began to add health concerns to their wider opposition. In the preceding years, health or noise complaints were rare despite large and small-turbine wind farms having operated for many years. Conclusions The reported historical and geographical variations in complaints are consistent with psychogenic hypotheses that expressed health problems are “communicated diseases” with nocebo effects likely to play an

Forest Disturbance Across the Conterminous United States from 1985-2012: The Emerging Dominance of Forest Decline

Science.gov (United States)

Cohen, Warren B.; Yang, Zhiqiang; Stehman, Stephen; Schroeder, Todd; Bell, David M.; Masek, Jeffrey; Huang, Chengquan; Meigs, Garrett W.

2015-01-01

Evidence of shifting dominance among major forest disturbance agent classes regionally to globally has been emerging in the literature. For example, climate-related stress and secondary stressors on forests (e.g., insect and disease, fire) have dramatically increased since the turn of the century globally, while harvest rates in the western US and elsewhere have declined. For shifts to be quantified, accurate historical forest disturbance estimates are required as a baseline for examining current trends. We report annual disturbance rates (with uncertainties) in the aggregate and by major change causal agent class for the conterminous US and five geographic subregions between 1985 and 2012. Results are based on human interpretations of Landsat time series from a probability sample of 7200 plots (30 m) distributed throughout the study area. Forest disturbance information was recorded with a Landsat time series visualization and data collection tool that incorporates ancillary high-resolution data. National rates of disturbance varied between 1.5% and 4.5% of forest area per year, with trends being strongly affected by shifting dominance among specific disturbance agent influences at the regional scale. Throughout the time series, national harvest disturbance rates varied between one and two percent, and were largely a function of harvest in the more heavily forested regions of the US (Mountain West, Northeast, and Southeast). During the first part of the time series, national disturbance rates largely reflected trends in harvest disturbance. Beginning in the mid-90s, forest decline-related disturbances associated with diminishing forest health (e.g., physiological stress leading to tree canopy cover loss, increases in tree mortality above background levels), especially in the Mountain West and Lowland West regions of the US, increased dramatically. Consequently, national disturbance rates greatly increased by 2000, and remained high for much of the decade. Decline

Impact of wind turbine sound on annoyance, self-reported sleep disturbance and psychological distress.

Science.gov (United States)

Bakker, R H; Pedersen, E; van den Berg, G P; Stewart, R E; Lok, W; Bouma, J

2012-05-15

The present government in the Netherlands intends to realize a substantial growth of wind energy before 2020, both onshore and offshore. Wind turbines, when positioned in the neighborhood of residents may cause visual annoyance and noise annoyance. Studies on other environmental sound sources, such as railway, road traffic, industry and aircraft noise show that (long-term) exposure to sound can have negative effects other than annoyance from noise. This study aims to elucidate the relation between exposure to the sound of wind turbines and annoyance, self-reported sleep disturbance and psychological distress of people that live in their vicinity. Data were gathered by questionnaire that was sent by mail to a representative sample of residents of the Netherlands living in the vicinity of wind turbines A dose-response relationship was found between immission levels of wind turbine sound and selfreported noise annoyance. Sound exposure was also related to sleep disturbance and psychological distress among those who reported that they could hear the sound, however not directly but with noise annoyance acting as a mediator. Respondents living in areas with other background sounds were less affected than respondents in quiet areas. People living in the vicinity of wind turbines are at risk of being annoyed by the noise, an adverse effect in itself. Noise annoyance in turn could lead to sleep disturbance and psychological distress. No direct effects of wind turbine noise on sleep disturbance or psychological stress has been demonstrated, which means that residents, who do not hear the sound, or do not feel disturbed, are not adversely affected. Copyright © 2012 Elsevier B.V. All rights reserved.

Disturbance Decoupling of Switched Linear Systems

NARCIS (Netherlands)

Yurtseven, E.; Heemels, W.P.M.H.; Camlibel, M.K.

2010-01-01

In this paper we consider disturbance decoupling problems for switched linear systems. We will provide necessary and sufficient conditions for three different versions of disturbance decoupling, which differ based on which signals are considered to be the disturbance. In the first version the

Disturbances in equilibrium function after major earthquake.

Science.gov (United States)

Honma, Motoyasu; Endo, Nobutaka; Osada, Yoshihisa; Kim, Yoshiharu; Kuriyama, Kenichi

2012-01-01

Major earthquakes were followed by a large number of aftershocks and significant outbreaks of dizziness occurred over a large area. However it is unclear why major earthquake causes dizziness. We conducted an intergroup trial on equilibrium dysfunction and psychological states associated with equilibrium dysfunction in individuals exposed to repetitive aftershocks versus those who were rarely exposed. Greater equilibrium dysfunction was observed in the aftershock-exposed group under conditions without visual compensation. Equilibrium dysfunction in the aftershock-exposed group appears to have arisen from disturbance of the inner ear, as well as individual vulnerability to state anxiety enhanced by repetitive exposure to aftershocks. We indicate potential effects of autonomic stress on equilibrium function after major earthquake. Our findings may contribute to risk management of psychological and physical health after major earthquakes with aftershocks, and allow development of a new empirical approach to disaster care after such events.

Perceptual accent rating and attribution in psychogenic FAS: some further evidence challenging Whitaker’s operational definition.

Directory of Open Access Journals (Sweden)

Stefanie eKeulen

2016-03-01

Full Text Available A 40-year-old, non-aphasic, right-handed, and polyglot (L1: French, L2: Dutch, L3: English woman with a 12 year history of addiction to opiates and psychoactive substances, and clear psychiatric problems, presented with a foreign accent of sudden onset in L1. Speech evolved towards a mostly fluent output, despite a stutter-like behavior and a marked grammatical output disorder. The psychogenic etiology of the accent foreignness was construed based upon the patient’s complex medical history, and psychodiagnostic, neuropsychological, and neurolinguistic assessments. The presence of a foreign accent was affirmed by a perceptual accent rating and attribution experiment. It is argued that this patient provides additional evidence demonstrating the outdatedness of Whitaker’s (1982 definition of Foreign Accent Syndrome, as only one of the four operational criteria was unequivocally applicable to our patient: her accent foreignness was not only recognized by her relatives and the medical staff, but also by a group of native French-speaking laymen. However, our patient defied the three remaining criteria, as central nervous system damage could not conclusively be demonstrated, psychodiagnostic assessment raised the hypothesis of a conversion disorder, and the patient was a polyglot whose newly gained accent was associated with a range of foreign languages, which exceeded the ones she spoke.

Patients with epilepsy and patients with psychogenic non-epileptic seizures: video-EEG, clinical and neuropsychological evaluation.

Science.gov (United States)

Turner, Katherine; Piazzini, Ada; Chiesa, Valentina; Barbieri, Valentina; Vignoli, Aglaia; Gardella, Elena; Tisi, Giuseppe; Scarone, Silvio; Canevini, Maria Paola; Gambini, Orsola

2011-11-01

The incidence of psychogenic non-epileptic seizures (PNES) is 4.9/100,000/year and it is estimated that about 20-30% of patients referred to tertiary care epilepsy centers for refractory seizures have both epilepsy and PNES. The purpose of our study is to evaluate psychiatric disorders and neuropsychological functions among patients with PNES, patients with epilepsy associated with PNES and patients with epilepsy. We evaluated 66 consecutive in-patients with video-EEG recordings: 21 patients with epilepsy, 22 patients with PNES and 10 patients with epilepsy associated with PNES; 13 patients were excluded (8 because of mental retardation and 5 because they did not present seizures or PNES during the recording period). All patients with PNES had a psychiatric diagnosis (100%) vs. 52% of patients with epilepsy. Cluster B personality disorders were more common in patients with PNES. We observed fewer mood and anxiety disorders in patients with PNES compared with those with epilepsy. We did not find statistically significant differences in neuropsychological profiles among the 3 patient groups. This study can help to contribute to a better understanding of the impact of PNES manifestations, in addition to the occurrence of seizures, in order to provide patients with more appropriate clinical, psychological and social care. Copyright © 2011 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

Disturbance analysis in nuclear power plants

International Nuclear Information System (INIS)

Sillamaa, M.A.

Disturbance analysis is any systematic procedure that helps an operator determine what has failed. This paper describes the typical information currently provided in CANDU power plants to help the operator respond to a disturbance. It presents a simplified model of how an operator could get into trouble, and briefly reviews development work on computerized disturbance analysis systems for nuclear power plants being done in various countries including Canada. Disturbance analysis systems promise to be useful tools in helping operators improve their response to complex situations. However, the originality and complexity of the work for a disturbance analysis system and the need to develop operator confidence and management support require a 'walk before you run' approach

Functional network connectivity underlying food processing: disturbed salience and visual processing in overweight and obese adults.

Science.gov (United States)

Kullmann, Stephanie; Pape, Anna-Antonia; Heni, Martin; Ketterer, Caroline; Schick, Fritz; Häring, Hans-Ulrich; Fritsche, Andreas; Preissl, Hubert; Veit, Ralf

2013-05-01

In order to adequately explore the neurobiological basis of eating behavior of humans and their changes with body weight, interactions between brain areas or networks need to be investigated. In the current functional magnetic resonance imaging study, we examined the modulating effects of stimulus category (food vs. nonfood), caloric content of food, and body weight on the time course and functional connectivity of 5 brain networks by means of independent component analysis in healthy lean and overweight/obese adults. These functional networks included motor sensory, default-mode, extrastriate visual, temporal visual association, and salience networks. We found an extensive modulation elicited by food stimuli in the 2 visual and salience networks, with a dissociable pattern in the time course and functional connectivity between lean and overweight/obese subjects. Specifically, only in lean subjects, the temporal visual association network was modulated by the stimulus category and the salience network by caloric content, whereas overweight and obese subjects showed a generalized augmented response in the salience network. Furthermore, overweight/obese subjects showed changes in functional connectivity in networks important for object recognition, motivational salience, and executive control. These alterations could potentially lead to top-down deficiencies driving the overconsumption of food in the obese population.

Visual body perception in anorexia nervosa.

Science.gov (United States)

Urgesi, Cosimo; Fornasari, Livia; Perini, Laura; Canalaz, Francesca; Cremaschi, Silvana; Faleschini, Laura; Balestrieri, Matteo; Fabbro, Franco; Aglioti, Salvatore Maria; Brambilla, Paolo

2012-05-01

Disturbance of body perception is a central aspect of anorexia nervosa (AN) and several neuroimaging studies have documented structural and functional alterations of occipito-temporal cortices involved in visual body processing. However, it is unclear whether these perceptual deficits involve more basic aspects of others' body perception. A consecutive sample of 15 adolescent patients with AN were compared with a group of 15 age- and gender-matched controls in delayed matching to sample tasks requiring the visual discrimination of the form or of the action of others' body. Patients showed better visual discrimination performance than controls in detail-based processing of body forms but not of body actions, which positively correlated with their increased tendency to convert a signal of punishment into a signal of reinforcement (higher persistence scores). The paradoxical advantage of patients with AN in detail-based body processing may be associated to their tendency to routinely explore body parts as a consequence of their obsessive worries about body appearance. Copyright © 2012 Wiley Periodicals, Inc.

The Disturbing Student and the Judicial Process

Science.gov (United States)

Ragle, John D.; Paine, Gage E.

2009-01-01

The Assessment-Intervention of Student Problems (AISP) model is a useful tool for preparing student affairs professionals to assess the problems of disturbed, disturbing, or disturbed/disturbing students and to make appropriate referrals. It is particularly useful because it emphasizes the necessity of developing an integrated system for this…

Implications of recurrent disturbance for genetic diversity.

Science.gov (United States)

Davies, Ian D; Cary, Geoffrey J; Landguth, Erin L; Lindenmayer, David B; Banks, Sam C

2016-02-01

Exploring interactions between ecological disturbance, species' abundances and community composition provides critical insights for ecological dynamics. While disturbance is also potentially an important driver of landscape genetic patterns, the mechanisms by which these patterns may arise by selective and neutral processes are not well-understood. We used simulation to evaluate the relative importance of disturbance regime components, and their interaction with demographic and dispersal processes, on the distribution of genetic diversity across landscapes. We investigated genetic impacts of variation in key components of disturbance regimes and spatial patterns that are likely to respond to climate change and land management, including disturbance size, frequency, and severity. The influence of disturbance was mediated by dispersal distance and, to a limited extent, by birth rate. Nevertheless, all three disturbance regime components strongly influenced spatial and temporal patterns of genetic diversity within subpopulations, and were associated with changes in genetic structure. Furthermore, disturbance-induced changes in temporal population dynamics and the spatial distribution of populations across the landscape resulted in disrupted isolation by distance patterns among populations. Our results show that forecast changes in disturbance regimes have the potential to cause major changes to the distribution of genetic diversity within and among populations. We highlight likely scenarios under which future changes to disturbance size, severity, or frequency will have the strongest impacts on population genetic patterns. In addition, our results have implications for the inference of biological processes from genetic data, because the effects of dispersal on genetic patterns were strongly mediated by disturbance regimes.

Is Developmental Dyslexia Modality Specific? A Visual-Auditory Comparison of Italian Dyslexics

Science.gov (United States)

Marinelli, Chiara Valeria; Angelelli, Paola; Di Filippo, Gloria; Zoccolotti, Pierluigi

2011-01-01

Although developmental dyslexia is often referred to as a cross-modal disturbance, tests of different modalities using the same stimuli are lacking. We compared the performance of 23 children with dyslexia and 42 chronologically matched control readers on reading versus repetition tasks and visual versus auditory lexical decision using the same…

Identification of Individuals with Serious Emotional Disturbance Using the Draw a Person: Screening Procedure for Emotional Disturbance.

Science.gov (United States)

McNeish, Timothy J.; Naglieri, Jack A.

1993-01-01

Regular education students (n=81) and students with serious emotional disturbance (n=81,) were matched on age (7-13), gender, race, and intelligence. They completed drawings which were scored using the "Draw a Person: Screening Procedure for Emotional Disturbance." Students with emotional disturbance scored significantly higher than did…

Sleep disturbances in Parkinsonism.

Science.gov (United States)

Askenasy, J J M

2003-02-01

The present article is meant to suggest an approach to the guidelines for the therapy of sleep disturbances in Parkinson's Disease (PD) patients.The factors affecting the quality of life in PD patients are depression, sleep disturbances and dependence. A large review of the literature on sleep disturbances in PD patients, provided the basis for the following classification of the sleep-arousal disturbances in PD patients. We suggest a model based on 3 steps in the treatment of sleep disturbances in PD patients. This model allowing the patient, the spouse or the caregiver a quiet sleep at night, may postpone the retirement and the institutionalization of the PD patient. I. Correct diagnosis of sleep disorders based on detailed anamnesis of the patient and of the spouse or of the caregiver. One week recording on a symptom diary (log) by the patient or the caregiver. Correct diagnosis of sleep disorders co morbidities. Selection of the most appropriate sleep test among: polysomnography (PSG), multiple sleep latency test (MSLT), multiple wake latency test (MWLT), Epworth Sleepiness Scale, actigraphy or video-PSG. II. The nonspecific therapeutic approach consists in: a) Checking the sleep effect on motor performance, is it beneficial, worse or neutral. b) Psycho-physical assistance. c) Dopaminergic adjustment is necessary owing to the progression of the nigrostriatal degeneration and the increased sensitivity of the terminals, which alter the normal modulator mechanisms of the motor centers in PD patients. Among the many neurotransmitters of the nigro-striatal pathway one can distinguish two with a major influence on REM and NonREM sleep. REM sleep corresponds to an increased cholinergic receptor activity and a decreased dopaminergic activity. This is the reason why REM sleep deprivation by suppressing cholinergic receptor activity ameliorates PD motor symptoms. L-Dopa and its agonists by suppressing cholinergic receptors suppress REM sleep. The permanent adjustment

Effect of neodymium:YAG laser capsulotomy on visual function in patients with posterior capsule opacification and good visual acuity.

Science.gov (United States)

Yotsukura, Erisa; Torii, Hidemasa; Saiki, Megumi; Negishi, Kazuno; Tsubota, Kazuo

2016-03-01

To evaluate the effect of neodymium:YAG (Nd:YAG) laser capsulotomy on the visual function in patients with posterior capsule opacification (PCO) and good visual acuity. Keio University Hospital, Tokyo, Japan. Observational case series. Eyes were evaluated that had previous cataract surgery with a clinical diagnosis of PCO requiring Nd:YAG laser capsulotomy regardless of a good corrected distance visual acuity (CDVA) (at least 20/20). The CDVA, 10% low contrast visual acuity (LCVA), wavefront aberrations from the 3rd to 6th order, and retinal straylight were measured before and after Nd:YAG laser capsulotomy. The study included 16 eyes of 16 patients (10 men, 6 women; mean age 69.5 years ± 9.3 [SD]). The mean CDVA, LCVA, and straylight after Nd:YAG laser capsulotomy improved significantly (P The root mean square (RMS) of the 3rd Zernike coefficients (S3) and the RMS of the total higher-order aberrations (HOAs) from the 3rd to 6th order decreased significantly after capsulotomy (P The straylight correlated significantly with the total HOAs (r = 0.727, P = .002) and S3 (r = 0.748, P = .001) before capsulotomy. Subjective symptoms resolved after capsulotomy in all cases. Neodymium:YAG laser capsulotomy enabled a significant improvement in visual function even in patients with PCO with good visual acuity. Straylight measurements might be useful to determine the indications for Nd:YAG laser capsulotomy when patients report visual disturbances without decreased visual acuity. Copyright © 2016 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Lingual and fusiform gyri in visual processing: a clinico-pathologic study of superior altitudinal hemianopia.

OpenAIRE

Bogousslavsky, J; Miklossy, J; Deruaz, J P; Assal, G; Regli, F

1987-01-01

A macular-sparing superior altitudinal hemianopia with no visuo-psychic disturbance, except impaired visual learning, was associated with bilateral ischaemic necrosis of the lingual gyrus and only partial involvement of the fusiform gyrus on the left side. It is suggested that bilateral destruction of the lingual gyrus alone is not sufficient to affect complex visual processing. The fusiform gyrus probably has a critical role in colour integration, visuo-spatial processing, facial recognition...

Latitudinal profile of the ionospheric disturbance dynamo magnetic signature: comparison with the DP2 magnetic disturbance

Directory of Open Access Journals (Sweden)

K. Z. Zaka

2009-09-01

Full Text Available During magnetic storms, the auroral electrojets intensification affects the thermospheric circulation on a global scale. This process which leads to electric field and current disturbance at middle and low latitudes, on the quiet day after the end of a storm, has been attributed to the ionospheric disturbance dynamo (Ddyn. The magnetic field disturbance observed as a result of this process is the reduction of the H component amplitude in the equatorial region which constitutes the main characteristic of the ionospheric disturbance dynamo process, associated with a westward electric current flow. The latitudinal profile of the Ddyn disturbance dynamo magnetic signature exhibits an eastward current at mid latitudes and a westward one at low latitudes with a substantial amplification at the magnetic equator. Such current flow reveals an "anti-Sq" system established between the mid latitudes and the equatorial region and opposes the normal Sq current vortex. However, the localization of the eastward current and consequently the position and the extent of the "anti-Sq" current vortex changes from one storm to another. Indeed, for a strong magnetic storm, the eastward current is well established at mid latitudes about 45° N and for a weak magnetic storm, the eastward current is established toward the high latitudes (about 60° N, near the Joule heating region, resulting in a large "anti-Sq" current cell. The latitudinal profile of the Ddyn disturbance as well as the magnetic disturbance DP2 generated by the mechanism of prompt penetration of the magnetospheric convection electric field in general, show a weak disturbance at the low latitudes with a substantial amplification at the magnetic equator. Due to the intensity of the storm, the magnitude of the DP2 appears higher than the Ddyn over the American and Asian sector contrary to the African sector.

Resources or landmarks: which factors drive homing success in Tetragonula carbonaria foraging in natural and disturbed landscapes?

Science.gov (United States)

Leonhardt, Sara D; Kaluza, Benjamin F; Wallace, Helen; Heard, Tim A

2016-10-01

To date, no study has investigated how landscape structural (visual) alterations affect navigation and thus homing success in stingless bees. We addressed this question in the Australian stingless bee Tetragonula carbonaria by performing marking, release and re-capture experiments in landscapes differing in habitat homogeneity (i.e., the proportion of elongated ground features typically considered prominent visual landmarks). We investigated how landscape affected the proportion of bees and nectar foragers returning to their hives as well as the earliest time bees and foragers returned. Undisturbed landscapes with few landmarks (that are conspicuous to the human eye) and large proportions of vegetation cover (natural forests) were classified visually/structurally homogeneous, and disturbed landscapes with many landmarks and fragmented or no extensive vegetation cover (gardens and plantations) visually/structurally heterogeneous. We found that proportions of successfully returning nectar foragers and earliest times first bees and foragers returned did not differ between landscapes. However, most bees returned in the visually/structurally most (forest) and least (garden) homogeneous landscape, suggesting that they use other than elongated ground features for navigation and that return speed is primarily driven by resource availability in a landscape.

Conservation of wildlife populations: factoring in incremental disturbance.

Science.gov (United States)

Stewart, Abbie; Komers, Petr E

2017-06-01

Progressive anthropogenic disturbance can alter ecosystem organization potentially causing shifts from one stable state to another. This potential for ecosystem shifts must be considered when establishing targets and objectives for conservation. We ask whether a predator-prey system response to incremental anthropogenic disturbance might shift along a disturbance gradient and, if it does, whether any disturbance thresholds are evident for this system. Development of linear corridors in forested areas increases wolf predation effectiveness, while high density of development provides a safe-haven for their prey. If wolves limit moose population growth, then wolves and moose should respond inversely to land cover disturbance. Using general linear model analysis, we test how the rate of change in moose ( Alces alces ) density and wolf ( Canis lupus ) harvest density are influenced by the rate of change in land cover and proportion of land cover disturbed within a 300,000 km 2 area in the boreal forest of Alberta, Canada. Using logistic regression, we test how the direction of change in moose density is influenced by measures of land cover change. In response to incremental land cover disturbance, moose declines occurred where 43% of land cover was disturbed and wolf density declined. Wolves and moose appeared to respond inversely to incremental disturbance with the balance between moose decline and wolf increase shifting at about 43% of land cover disturbed. Conservation decisions require quantification of disturbance rates and their relationships to predator-prey systems because ecosystem responses to anthropogenic disturbance shift across disturbance gradients.

Comparison of visual outcomes and subjective visual quality after bilateral implantation of a diffractive trifocal intraocular lens and blended implantation of apodized diffractive bifocal intraocular lenses

Directory of Open Access Journals (Sweden)

Gundersen KG

2016-05-01

Full Text Available Kjell G Gundersen,1 Rick Potvin21IFocus Øyeklinikk AS, Haugesund, Norway; 2Science in Vision, Akron, NY, USAPurpose: To compare the visual acuity (VA and quality of vision between bilateral implantation of a trifocal intraocular lens (IOL and blended bifocal IOLs with an intermediate add in the dominant eye and a near add in the nondominant eye.Patients and methods: Patients with either trifocal or blended bifocal IOLs implanted were recruited after surgery. Subjects returned for a single diagnostic visit between 3 and 24 months after surgery. VA was tested at various distances, including low-contrast acuity and acuity at their preferred reading distance. A binocular defocus curve was obtained, and subjective visual function and quality of vision were evaluated.Results: Twenty-five trifocal subjects and 30 blended bifocal subjects were enrolled. There were no significant differences in low-contrast acuity, preferred reading distance, or acuity at that reading distance. Binocular vision at 4 m, 60 cm, and 40 cm was not statistically significantly different. The trifocal provided statistically significantly better visual acuity (P<0.05 at vergences from -0.5 to -1.5 D (from 2 m to 67 cm viewing distance, P<0.05. There was no statistically significant difference in the near vision subscale scores of the 39-question National Eye Institute Visual Function Questionnaire or the overall scores of the Quality of Vision questionnaire, though significantly more trifocal subjects reported that the observed visual disturbances were “bothersome” (P<0.05.Conclusion: Both lens modalities provided subjects with excellent binocular near and distance vision, with similar low rates of visual disturbances and good reported functional vision. The trifocal IOL provided significantly better intermediate VA in the viewing distance range of 2 m to 67 cm, corresponding to viewing things such as a car dashboard or grocery shelf. VA was similar between groups at

Pain and other symptoms of CRPS can be increased by ambiguous visual stimuli--an exploratory study.

Science.gov (United States)

Hall, Jane; Harrison, Simon; Cohen, Helen; McCabe, Candida S; Harris, N; Blake, David R

2011-01-01

Visual disturbance, visuo-spatial difficulties, and exacerbations of pain associated with these, have been reported by some patients with Complex Regional Pain Syndrome (CRPS). We investigated the hypothesis that some visual stimuli (i.e. those which produce ambiguous perceptions) can induce pain and other somatic sensations in people with CRPS. Thirty patients with CRPS, 33 with rheumatology conditions and 45 healthy controls viewed two images: a bistable spatial image and a control image. For each image participants recorded the frequency of percept change in 1 min and reported any changes in somatosensation. 73% of patients with CRPS reported increases in pain and/or sensory disturbances including changes in perception of the affected limb, temperature and weight changes and feelings of disorientation after viewing the bistable image. Additionally, 13% of the CRPS group responded with striking worsening of their symptoms which necessitated task cessation. Subjects in the control groups did not report pain increases or somatic sensations. It is possible to worsen the pain suffered in CRPS, and to produce other somatic sensations, by means of a visual stimulus alone. This is a newly described finding. As a clinical and research tool, the experimental method provides a means to generate and exacerbate somaesthetic disturbances, including pain, without moving the affected limb and causing nociceptive interference. This may be particularly useful for brain imaging studies. Copyright © 2010 European Federation of International Association for the Study of Pain Chapters. Published by Elsevier Ltd. All rights reserved.

Concepts and Challenges in Disturbance Hydrology

Science.gov (United States)

Ebel, B. A.; Mirus, B. B.

2016-12-01

Landscape disturbances are increasing, often promoted and enhanced by climate shifts and human activities. Insect infestations, wildfires, earthquakes, urban development, forest harvest, mineral and petroleum resource extraction, and hurricanes are common landscape disturbances that can have profound hydrologic consequences. These cause relatively abrupt changes in the landscape, which alter local processes on plots and hillslopes in addition to coarser-scale processes across watersheds through cross-scale interactions. Shifts in soil properties and cover of vegetation and leaf litter change the water storage or buffering capacity as well as the hydrologic functional connectivity across multiple scales. These changes increase the risk of catastrophic flooding, erosion, and mass movements that degrade water resources, ecosystem services, and protection from hydrologically driven natural hazards. Although it is imperative that we understand the hydrologic effects of these disturbances, several major barriers exist. Four challenges are: (i) overlapping disturbances in space and time with unknown recovery trajectories, (ii) a paucity of long-term recovery records (>5 years duration), (iii) inefficacy of traditional modeling and parameterization approaches, and (iv) lack of pre-disturbance characterization. Examples of these challenges will be presented along with proposed opportunities for improved mechanistic understanding of processes and thresholds in disturbance hydrology.

Nonunity gain minimal-disturbance measurement

DEFF Research Database (Denmark)

Sabuncu, Metin; Mišta, L.; Fiurášek, J.

2007-01-01

We propose and experimentally demonstrate an optimal nonunity gain Gaussian scheme for partial measurement of an unknown coherent state that causes minimal disturbance of the state. The information gain and the state disturbance are quantified by the noise added to the measurement outcomes...

Influence of disturbance on temperate forest productivity

Science.gov (United States)

Peters, Emily B.; Wythers, Kirk R.; Bradford, John B.; Reich, Peter B.

2013-01-01

Climate, tree species traits, and soil fertility are key controls on forest productivity. However, in most forest ecosystems, natural and human disturbances, such as wind throw, fire, and harvest, can also exert important and lasting direct and indirect influence over productivity. We used an ecosystem model, PnET-CN, to examine how disturbance type, intensity, and frequency influence net primary production (NPP) across a range of forest types from Minnesota and Wisconsin, USA. We assessed the importance of past disturbances on NPP, net N mineralization, foliar N, and leaf area index at 107 forest stands of differing types (aspen, jack pine, northern hardwood, black spruce) and disturbance history (fire, harvest) by comparing model simulations with observations. The model reasonably predicted differences among forest types in productivity, foliar N, leaf area index, and net N mineralization. Model simulations that included past disturbances minimally improved predictions compared to simulations without disturbance, suggesting the legacy of past disturbances played a minor role in influencing current forest productivity rates. Modeled NPP was more sensitive to the intensity of soil removal during a disturbance than the fraction of stand mortality or wood removal. Increasing crown fire frequency resulted in lower NPP, particularly for conifer forest types with longer leaf life spans and longer recovery times. These findings suggest that, over long time periods, moderate frequency disturbances are a relatively less important control on productivity than climate, soil, and species traits.

Finding disturbances in on-farm biogas production.

Science.gov (United States)

Antonio, Pereira-Querol Marco; Laura, Seppänen

2012-01-01

When implementing innovations, disturbances are very likely to take place. Disturbances are undesirable because they can lead to unwanted outcomes, such as economic losses and work overload to workers. However, they can be powerful opportunities for learning and re-designing innovations. Here, we will present activity theoretical tools for analyzing disturbances in a way that they could be used as learning opportunities. We illustrate the proposed tools by analyzing a disturbance that took place during the implementation of a project of biogas production. By interpreting the disturbance process with a network of activity systems, we found that on-farm disturbances were formed as ruptures, innovations and asynchronies originated in other activity systems. This finding suggests that disturbances are outcomes of the functioning of networks, rather than simple results of failure of individuals or technical devices. The proposed tools could be used in interventions to help practitioners and ergonomists to recognize the systemic and networked nature of problems, and therefore, realize that they may require the collaboration of actors from different activities. In this sense, disturbances may be turned into opportunities for learning and developing innovations. We conclude by discussing how the method could be used in ergonomic design and intervention.

Sleep disturbances and glucose homeostasis

NARCIS (Netherlands)

Barf, R. Paulien; Scheurink, Anton J.W.

2011-01-01

Sleep disturbances, induced by either lifestyle, shift work or sleeping disorders, have become more prevalent in our 24/7 Western society. Sleep disturbances are associated with impaired health including metabolic diseases such as obesity and type 2 diabetes. The question remains whether there is a

Modelling natural disturbances in forest ecosystems: a review

OpenAIRE

Seidl, Rupert; Fernandes, Paulo M.; Fonseca, Teresa F.; Gillet, François; Jönsson, Anna Maria; Merganičová, Katarína; Netherer, Sigrid; Arpaci, Alexander; Bontemps, Jean-Daniel; Bugmann, Harald

2011-01-01

Natural disturbances play a key role in ecosystem dynamics and are important factors for sustainable forest ecosystem management. Quantitative models are frequently employed to tackle the complexities associated with disturbance processes. Here we review the wide variety of approaches to modelling natural disturbances in forest ecosystems, addressing the full spectrum of disturbance modelling from single events to integrated disturbance regimes. We applied a general, process-based framework f...

The seam visual tracking method for large structures

Science.gov (United States)

Bi, Qilin; Jiang, Xiaomin; Liu, Xiaoguang; Cheng, Taobo; Zhu, Yulong

2017-10-01

In this paper, a compact and flexible weld visual tracking method is proposed. Firstly, there was the interference between the visual device and the work-piece to be welded when visual tracking height cannot change. a kind of weld vision system with compact structure and tracking height is researched. Secondly, according to analyze the relative spatial pose between the camera, the laser and the work-piece to be welded and study with the theory of relative geometric imaging, The mathematical model between image feature parameters and three-dimensional trajectory of the assembly gap to be welded is established. Thirdly, the visual imaging parameters of line structured light are optimized by experiment of the weld structure of the weld. Fourth, the interference that line structure light will be scatters at the bright area of metal and the area of surface scratches will be bright is exited in the imaging. These disturbances seriously affect the computational efficiency. The algorithm based on the human eye visual attention mechanism is used to extract the weld characteristics efficiently and stably. Finally, in the experiment, It is verified that the compact and flexible weld tracking method has the tracking accuracy of 0.5mm in the tracking of large structural parts. It is a wide range of industrial application prospects.

The intermediate disturbance hypothesis applies to tropical forests, but disturbance contributes little to tree diversity

NARCIS (Netherlands)

Bongers, F.; Poorter, L.; Hawthorne, W.D.; Sheil, D.

2009-01-01

The intermediate disturbance hypothesis (IDH) predicts local species diversity to be maximal at an intermediate level of disturbance. Developed to explain species maintenance and diversity patterns in species-rich ecosystems such as tropical forests, tests of IDH in tropical forest remain scarce,

Relative impact of previous disturbance history on the likelihood of additional disturbance in the Northern United States Forest Service USFS Region

Science.gov (United States)

Hernandez, A. J.

2015-12-01

The Landsat archive is increasingly being used to detect trends in the occurrence of forest disturbance. Beyond information about the amount of area affected, forest managers need to know if and how disturbance regimes change. The National Forest System (NFS) has developed a comprehensive plan for carbon monitoring that requires a detailed temporal mapping of forest disturbances across 75 million hectares. A long-term annual time series that shows the timing, extent, and type of disturbance beginning in 1990 and ending in 2011 has been prepared for several USFS Regions, including the Northern Region. Our mapping starts with an automated detection of annual disturbances using a time series of historical Landsat imagery. Automated detections are meticulously inspected, corrected and labeled using various USFS ancillary datasets. The resulting maps of verified disturbance show the timing and types are fires, harvests, insect activity, disease, and abiotic (wind, drought, avalanche) damage. Also, the magnitude of each change event is modeled in terms of the proportion of canopy cover lost. The sequence of disturbances for every pixel since 1990 has been consistently mapped and is available across the entirety of NFS. Our datasets contain sufficient information to describe the frequency of stand replacement, as well as how often disturbance results in only a partial loss of canopy. This information provides empirical insight into how an initial disturbance may predispose a stand to further disturbance, and it also show a climatic signal in the occurrence of processes such as fire and insect epidemics. Thus, we have the information to model the likelihood of occurrence of certain disturbances after a given event (i.e. if we have a fire in the past what does that do to the likelihood of occurrence of insects in the future). Here, we explore if previous disturbance history is a reliable predictor of additional disturbance in the future and we present results of applying

Visual impact of overhead power transmission lines and dielectric and corona effects constraints on insulation coordination

International Nuclear Information System (INIS)

Deponti, F.; Fini, G.P.; Porrino, A.; Rosa, F.

1992-06-01

In assessing overhead power transmission line design and planning criteria for the optimization of visual impact, safety and the reduction of electro magnetic disturbance effects, this paper reviews the research findings of ENEL, the Italian Electricity Board. The on-going research activities involve theoretical calculations and laboratory performance tests to determine the best compact configurations for 380 kV lines. The parameters under examination include: insulator spacing, sizing and salt fog resistivity; allowable overvoltages; maximum line length; behaviour in lightning conditions; radio and acoustics disturbances

Visual binding abilities in the initial and advanced stages of schizophrenia

DEFF Research Database (Denmark)

Parnas, J; Vianin, P; Saebye, D

2001-01-01

OBJECTIVE: The study tests the hypothesis that intramodal visual binding is disturbed in schizophrenia and should be detectable in all illness stages as a stable trait marker. METHOD: Three groups of patients (rehospitalized chronic schizophrenic, first admitted schizophrenic and schizotypal...... patients believed to be suffering from a pre-schizophrenic prodrome) and a group of normal control subjects were tested on three tasks targeting visual 'binding' abilities (Muller-Lyer's illusion and two figure detection tasks) in addition to control parameters such as reaction time, visual selective...... attention, Raven's test and two conventional cortical tasks of spatial working memory (SWM) and a global local test. RESULTS: Chronic patients had a decreased performance on the binding tests. Unexpectedly, the prodromal group exhibited an enhanced Gestalt extraction on these tests compared both...

Disturbance History,Spatial Variability, and Patterns of Biodiversity

Science.gov (United States)

Bendix, J.; Wiley, J. J.; Commons, M.

2012-12-01

The intermediate disturbance hypothesis predicts that species diversity will be maximized in environments experiencing intermediate intensity disturbance, after an intermediate timespan. Because many landscapes comprise mosaics with complex disturbance histories, the theory implies that each patch in those mosaics should have a distinct level of diversity reflecting combined impact of the magnitude of disturbance and the time since it occurred. We modeled the changing patterns of species richness across a landscape experiencing varied scenarios of simulated disturbance. Model outputs show that individual landscape patches have highly variable species richness through time, with the details reflecting the timing, intensity and sequence of their disturbance history. When the results are mapped across the landscape, the resulting temporal and spatial complexity illustrates both the contingent nature of diversity and the danger of generalizing about the impacts of disturbance.

The interplay between climate change, forests, and disturbances

Science.gov (United States)

Virginia H. Dale; Linda A. Joyce; Steve McNulty; Ronald P. Neilson

2000-01-01

Climate change affects forests both directly and indirectly through disturbances. Disturbances are a natural and integral part of forest ecosystems, and climate change can alter these natural interactions. When disturbances exceed their natural range of variation, the change in forest structure and function may be extreme. Each disturbance affects forests differently....

Temporal and spatial evolution characteristics of disturbance wave in a hypersonic boundary layer due to single-frequency entropy disturbance.

Science.gov (United States)

Wang, Zhenqing; Tang, Xiaojun; Lv, Hongqing; Shi, Jianqiang

2014-01-01

By using a high-order accurate finite difference scheme, direct numerical simulation of hypersonic flow over an 8° half-wedge-angle blunt wedge under freestream single-frequency entropy disturbance is conducted; the generation and the temporal and spatial nonlinear evolution of boundary layer disturbance waves are investigated. Results show that, under the freestream single-frequency entropy disturbance, the entropy state of boundary layer is changed sharply and the disturbance waves within a certain frequency range are induced in the boundary layer. Furthermore, the amplitudes of disturbance waves in the period phase are larger than that in the response phase and ablation phase and the frequency range in the boundary layer in the period phase is narrower than that in these two phases. In addition, the mode competition, dominant mode transformation, and disturbance energy transfer exist among different modes both in temporal and in spatial evolution. The mode competition changes the characteristics of nonlinear evolution of the unstable waves in the boundary layer. The development of the most unstable mode along streamwise relies more on the motivation of disturbance waves in the upstream than that of other modes on this motivation.

Natural disturbance impacts on Canada's forest carbon budget

International Nuclear Information System (INIS)

Kurz, W.

2004-01-01

Wildfire and insect outbreaks are major determinants of forest dynamics in Canada, transferring carbon within the ecosystem, releasing carbon into the atmosphere and influencing post-disturbance carbon dynamics. This paper discusses the impacts of global climate change on natural disturbances. Higher temperatures and drier conditions are likely to increase burned areas in Canada and will also increase the impacts of insects, allowing for an expanded range and stressing their host species. Long-term changes in disturbance regimes have already affected Canada's forest age-class structure. Statistics of lower disturbance periods and carbon production were compared with periods of higher disturbance. Scenario analyses were conducted for the period of 1996 to 2032, assuming that annual insect and fire disturbance rates in timber-productive forests were 20 per cent higher and carbon production 20 per cent lower than base scenarios using average disturbance rates. It was concluded that these conditions could cause carbon stocks in Canada's forests to decline. The future carbon balance of Canada's forests will be affected by the rate of natural and human-induced disturbances. 4 refs

Recovery of lotic macroinvertebrate communities from disturbance

Science.gov (United States)

Wallace, J. Bruce

1990-09-01

Ecosystem disturbances produce changes in macrobenthic community structure (abundances, biomass, and production) that persist for a few weeks to many decades. Examples of disturbances with extremely long-term effects on benthic communities include contamination by persistent toxic agents, physical changes in habitats, and altered energy inputs. Stream size, retention, and local geomorphology may ameliorate the influence of disturbances on invertebrates. Disturbances can alter food webs and may select for favorable genotypes (e.g., insecticidal resistance). Introductions of pesticides into lotic ecosystems, which do not result in major physical changes within habitats, illustrate several factors that influence invertebrate recovery time from disturbance. These include: (1) magnitude of original contamination, toxicity, and extent of continued use; (2) spatial scale of the disturbance; (3) persistence of the pesticide; (4) timing of the contamination in relation to the life history stages of the organisms; (5) vagility of populations influenced by pesticides; and (6) position within the drainage network. The ability of macroinvertebrates to recolonize denuded stream habitats may vary greatly depending on regional life histories, dispersal abilities, and position within the stream network (e.g., headwaters vs larger rivers). Although downstream drift is the most frequently cited mechanism of invertebrate recolonization following disturbance in middle- and larger-order streams, evidence is presented that shows aerial recolonization to be potentially important in headwater streams. There is an apparent stochastic element operating for aerial recolonization, depending on the timing of disturbance and flight periods of various taxa. Available evidence indicates that recolonization of invertebrate taxa without an aerial adult stage requires longer periods of time than for those that possess winged, terrestrial adult stages (i.e., most insects). Innovative, manipulative

LSD Flashbacks - The Appearance of New Visual Imagery Not Experienced During Initial Intoxication: Two Case Reports.

Science.gov (United States)

G Lerner, Arturo; Goodman, Craig; Rudinski, Dmitri; Lev-Ran, Shaul

2014-01-01

A side effect associated with the use of synthetic hallucinogens such as lysergic acid diethylamide-(LSD) is the partial or total recurrence of perceptual disturbances which previously appeared during intoxication, despite absence of recent use. These are commonly referred to as "flashbacks" or Hallucinogen Persisting Perception Disorder (HPPD). Here we present two cases of patients with a prior history of LSD use who turned to psychiatric consultation following brief episodes of HPPD. Surprisingly, in both cases new visual imagery appeared during episodes of flashbacks which was not experienced during primary LSD use. Both subjects reported the ability to discern between LSD-associated visual disturbances and new visual imagery. This phenomenon did not cause functional impairment and in both cases caused gradual concern due to its persistence. Both patients refused medical treatment and continued psychiatric follow-up. At one year follow-up both patients reported almost complete spontaneous remission. To the best of our knowledge these are the first reported cases of LSD-related benign flashbacks in which new imagery is experienced. Reasons for this reversible and apparently harmless side effect are proposed. Conclusions from case reports should be taken with caution.

Computer aided analysis of disturbances

International Nuclear Information System (INIS)

Baldeweg, F.; Lindner, A.

1986-01-01

Computer aided analysis of disturbances and the prevention of failures (diagnosis and therapy control) in technological plants belong to the most important tasks of process control. Research in this field is very intensive due to increasing requirements to security and economy of process control and due to a remarkable increase of the efficiency of digital electronics. This publication concerns with analysis of disturbances in complex technological plants, especially in so called high risk processes. The presentation emphasizes theoretical concept of diagnosis and therapy control, modelling of the disturbance behaviour of the technological process and the man-machine-communication integrating artificial intelligence methods, e.g., expert system approach. Application is given for nuclear power plants. (author)

Hydrological disturbance diminishes predator control in wetlands.

Science.gov (United States)

Dorn, Nathan J; Cook, Mark I

2015-11-01

Effects of predators on prey populations can be especially strong in aquatic ecosystems, but disturbances may mediate the strength of predator limitation and even allow outbreaks of some prey populations. In a two-year study we investigated the numerical responses of crayfish (Procambarus fallax) and small fishes (Poeciliidae and Fundulidae) to a brief hydrological disturbance in replicated freshwater wetlands with an experimental drying and large predatory fish reduction. The experiment and an in situ predation assay tested the component of the consumer stress model positing that disturbances release prey from predator limitation. In the disturbed wetlands, abundances of large predatory fish were seasonally reduced, similar to dynamics in the Everglades (southern Florida). Densities of small fish were unaffected by the disturbance, but crayfish densities, which were similar across all wetlands before drying, increased almost threefold in the year after the disturbance. Upon re-flooding, juvenile crayfish survival was inversely related to the abundance of large fish across wetlands, but we found no evidence for enhanced algal food quality. At a larger landscape scale (500 km2 of the Everglades), crayfish densities over eight years were positively correlated with the severity of local dry disturbances (up to 99 days dry) during the preceding dry season. In contrast, densities of small-bodied fishes in the same wetlands were seasonally depressed by dry disturbances. The results from our experimental wetland drought and the observations of crayfish densities in the Everglades represent a large-scale example of prey population release following a hydrological disturbance in a freshwater ecosystem. The conditions producing crayfish pulses in the Everglades appear consistent with the mechanics of the consumer stress model, and we suggest crayfish pulses may influence the number of nesting wading birds in the Everglades.

Sleep disturbances after non-cardiac surgery

DEFF Research Database (Denmark)

Rosenberg, Jacob

2001-01-01

. The sleep disturbances seem to be related to the magnitude of trauma and thereby to the surgical stress response and/or post-operative opioid administration. Post-operative sleep disturbances may contribute to the development of early post-operative fatigue, episodic hypoxaemia, haemodynamic instability......After major non-cardiac surgery sleep pattern is usually disturbed with initial suppression of rapid eye movement sleep with a subsequent rebound during the first post-operative week. Deep sleep is also suppressed for several days after the operation and subjective sleep quality is impaired...... and altered mental status, all with a potential negative effect on post-operative outcome. Minimizing surgical trauma and avoiding or minimizing use of opioids for pain relief may prevent or reduce post-operative sleep disturbances. Post-operative sleep pattern represents an important research field, since...

Information-disturbance tradeoff in quantum measurements

International Nuclear Information System (INIS)

Maccone, Lorenzo

2006-01-01

We present a simple information-disturbance tradeoff relation valid for any general measurement apparatus: The disturbance between input and output states is lower bounded by the information the apparatus provides in distinguishing these two states

Neuropsychiatry of complex visual hallucinations.

Science.gov (United States)

Mocellin, Ramon; Walterfang, Mark; Velakoulis, Dennis

2006-09-01

To describe the phenomenology and pathophysiology of complex visual hallucinations (CVH) in various organic states, in particular Charles Bonnet syndrome and peduncular hallucinosis. Three cases of CVH in the setting of pontine infarction, thalamic infarction and temporoparietal epileptiform activity are presented and the available psychiatric, neurological and biological literature on the structures of the central nervous system involved in producing hallucinatory states is reviewed. Complex visual hallucinations can arise from a variety of processes involving the retinogeniculocalcarine tract, or ascending brainstem modulatory structures. The cortical activity responsible for hallucinations results from altered or reduced input into these regions, or a loss of ascending inhibition of their afferent pathways. A significant degree of overlaps exists between the concepts of Charles Bonnet syndrome and peduncular hallucinosis. The fluidity of these eponymous syndromes reduces their validity and meaning, and may result in an inappropriate attribution of the underlying pathology. An understanding of how differing pathologies may produce CVH allows for the appropriate tailoring of treatment, depending on the site and nature of the lesion and content of perceptual disturbance.

Clinical Features of Psychogenic Voice Disorder and the Efficiency of Voice Therapy and Psychological Evaluation.

Science.gov (United States)

Tezcaner, Zahide Çiler; Gökmen, Muhammed Fatih; Yıldırım, Sibel; Dursun, Gürsel

2017-11-06

The aim of this study was to define the clinical features of psychogenic voice disorder (PVD) and explore the treatment efficiency of voice therapy and psychological evaluation. Fifty-eight patients who received treatment following the PVD diagnosis and had no organic or other functional voice disorders were assessed retrospectively based on laryngoscopic examinations and subjective and objective assessments. Epidemiological characteristics, accompanying organic and psychological disorders, preferred methods of treatment, and previous treatment outcomes were examined for each patient. A comparison was made based on voice disorders and responses to treatment between patients who received psychotherapy and patients who did not. Participants in this study comprised 58 patients, 10 male and 48 female. Voice therapy was applied in all patients, 54 (93.1%) of whom had improvement in their voice. Although all patients were advised to undergo psychological assessment, only 60.3% (35/58) of them underwent psychological assessment. No statistically significant difference was found between patients who did receive psychological support concerning their treatment responses and patients who did not. Relapse occurred in 14.7% (5/34) of the patients who applied for psychological assessment and in 50% (10/20) of those who did not. There was a statistically significant difference in relapse rates, which was higher among patients who did not receive psychological support (P therapy is an efficient treatment method for PVD. However, in the long-term follow-up, relapse of the disease is observed to be higher among patients who failed to follow up on the recommendation for psychological assessment. Copyright © 2017 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

Four-level time decomposition quasi-static power flow and successive disturbances analysis. [Power system disturbances

Energy Technology Data Exchange (ETDEWEB)

Jovanovic, S M [Nikola Tesla Inst., Belgrade (YU)

1990-01-01

This paper presents a model and an appropriate numerical procedure for a four-level time decomposition quasi-static power flow and successive disturbances analysis of power systems. The analysis consists of the sequential computation of the zero, primary, secondary and tertiary quasi-static states and of the estimation of successive structural disturbances during the 1200 s dynamics after a structural disturbance. The model is developed by detailed inspection of the time decomposition characteristics of automatic protection and control devices. Adequate speed of the numerical procedure is attained by a specific application of the inversion matrix lemma and the decoupled model constant coefficient matrices. The four-level time decomposition quasi-static method is intended for security and emergency analysis. (author).

SPEECH VISUALIZATION SISTEM AS A BASIS FOR SPEECH TRAINING AND COMMUNICATION AIDS

Directory of Open Access Journals (Sweden)

Oliana KRSTEVA

1997-09-01

Full Text Available One receives much more information through a visual sense than through a tactile one. However, most visual aids for hearing-impaired persons are not wearable because it is difficult to make them compact and it is not a best way to mask always their vision.Generally it is difficult to get the integrated patterns by a single mathematical transform of signals, such as a Foruier transform. In order to obtain the integrated pattern speech parameters should be carefully extracted by an analysis according as each parameter, and a visual pattern, which can intuitively be understood by anyone, must be synthesized from them. Successful integration of speech parameters will never disturb understanding of individual features, so that the system can be used for speech training and communication.

Microgravity Disturbance Predictions in the Combustion Integrated Rack

Science.gov (United States)

Just, M.; Grodsinsky, Carlos M.

2002-01-01

This paper will focus on the approach used to characterize microgravity disturbances in the Combustion Integrated Rack (CIR), currently scheduled for launch to the International Space Station (ISS) in 2005. Microgravity experiments contained within the CIR are extremely sensitive to vibratory and transient disturbances originating on-board and off-board the rack. Therefore, several techniques are implemented to isolate the critical science locations from external vibration. A combined testing and analysis approach is utilized to predict the resulting microgravity levels at the critical science location. The major topics to be addressed are: 1) CIR Vibration Isolation Approaches, 2) Disturbance Sources and Characterization, 3) Microgravity Predictive Modeling, 4) Science Microgravity Requirements, 6) Microgravity Control, and 7) On-Orbit Disturbance Measurement. The CIR is using the Passive Rack Isolation System (PaRIS) to isolate the rack from offboard rack disturbances. By utilizing this system, CIR is connected to the U.S. Lab module structure by either 13 or 14 umbilical lines and 8 spring / damper isolators. Some on-board CIR disturbers are locally isolated by grommets or wire ropes. CIR's environmental and science on board support equipment such as air circulation fans, pumps, water flow, air flow, solenoid valves, and computer hard drives cause disturbances within the rack. These disturbers along with the rack structure must be characterized to predict whether the on-orbit vibration levels during experimentation exceed the specified science microgravity vibration level requirements. Both vibratory and transient disturbance conditions are addressed. Disturbance levels/analytical inputs are obtained for each individual disturber in a "free floating" condition in the Glenn Research Center (GRC) Microgravity Emissions Lab (MEL). Flight spare hardware is tested on an Orbital Replacement Unit (ORU) basis. Based on test and analysis, maximum disturbance level

Sleep-wake disturbances after traumatic brain injury.

Science.gov (United States)

Ouellet, Marie-Christine; Beaulieu-Bonneau, Simon; Morin, Charles M

2015-07-01

Sleep-wake disturbances are extremely common after a traumatic brain injury (TBI). The most common disturbances are insomnia (difficulties falling or staying asleep), increased sleep need, and excessive daytime sleepiness that can be due to the TBI or other sleep disorders associated with TBI, such as sleep-related breathing disorder or post-traumatic hypersomnia. Sleep-wake disturbances can have a major effect on functional outcomes and on the recovery process after TBI. These negative effects can exacerbate other common sequelae of TBI-such as fatigue, pain, cognitive impairments, and psychological disorders (eg, depression and anxiety). Sleep-wake disturbances associated with TBI warrant treatment. Although evidence specific to patients with TBI is still scarce, cognitive-behavioural therapy and medication could prove helpful to alleviate sleep-wake disturbances in patients with a TBI. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Storm Time Evolution of the Ionospheric Disturbance Plasma Drifts

Science.gov (United States)

Zhang, Ruilong; Liu, Libo; Le, Huijun; Chen, Yiding; Kuai, Jiawei

2017-11-01

In this paper, we use the C/NOFS and ROCSAT-1 satellites observations to analyze the storm time evolution of the disturbance plasma drifts in a 24 h local time scale during three magnetic storms driven by long-lasting southward IMF Bz. The disturbance plasma drifts during the three storms present some common features in the periods dominated by the disturbance dynamo. The newly formed disturbance plasma drifts are upward and westward at night, and downward and eastward during daytime. Further, the disturbance plasma drifts are gradually evolved to present significant local time shifts. The westward disturbance plasma drifts gradually migrate from nightside to dayside. Meanwhile, the dayside downward disturbance plasma drifts become enhanced and shift to later local time. The local time shifts in disturbance plasma drifts are suggested to be mainly attributed to the evolution of the disturbance winds. The strong disturbance winds arisen around midnight can constantly corotate to later local time. At dayside the westward and equatorward disturbance winds can drive the F region dynamo to produce the poleward and westward polarization electric fields (or the westward and downward disturbance drifts). The present results indicate that the disturbance winds corotated to later local time can affect the local time features of the disturbance dynamo electric field.

Managing Sleep Disturbances in Cirrhosis

Directory of Open Access Journals (Sweden)

Xun Zhao

2016-01-01

Full Text Available Sleep disturbances, particularly daytime sleepiness and insomnia, are common problems reported by patients suffering from liver cirrhosis. Poor sleep negatively impacts patients’ quality of life and cognitive functions and increases mortality. Although sleep disturbances can be an early sign of hepatic encephalopathy (HE, many patients without HE still complain of poor quality sleep. The pathophysiology of these disturbances is not fully understood but is believed to be linked to impaired hepatic melatonin metabolism. This paper provides an overview for the clinician of common comorbidities contributing to poor sleep in patients with liver disease, mainly restless leg syndrome and obstructive sleep apnea. It discusses nondrug and pharmacologic treatment options in these patients, such as the use of light therapy and histamine (H1 blockers.

Disturbance alters local-regional richness relationships in appalachian forests

Science.gov (United States)

Belote, R.T.; Sanders, N.J.; Jones, R.H.

2009-01-01

Whether biological diversity within communities is limited by local interactions or regional species pools remains an important question in ecology. In this paper, we investigate how an experimentally applied tree-harvesting disturbance gradient influenced local-regional richness relationships. Plant species richness was measured at three spatial scales (2 ha = regional; 576 m2 and 1 m2 = local) on three occasions (one year pre-disturbance, one year post-disturbance, and 10 years post-disturbance) across five disturbance treatments (uncut control through clearcut) replicated throughout the southern Appalachian Mountains, USA. We investigated whether species richness in 576-m2 plots and 1-m2 subplots depended on species richness in 2-ha experimental units and whether this relationship changed through time before and after canopy disturbance. We found that, before disturbance, the relationship between local and regional richness was weak or nonexistent. One year after disturbance local richness was a positive function of regional richness, because local sites were colonized from the regional species pool. Ten years after disturbance, the positive relationship persisted, but the slope had decreased by half. These results suggest that disturbance can set the stage for strong influences of regional species pools on local community assembly in temperate forests. However, as time since disturbance increases, local controls on community assembly decouple the relationships between regional and local diversity. ?? 2009 by the Ecological Society of America.

Comparative evaluation of audio and audio - tactile methods to improve oral hygiene status of visually impaired school children

OpenAIRE

R Krishnakumar; Swarna Swathi Silla; Sugumaran K Durai; Mohan Govindarajan; Syed Shaheed Ahamed; Logeshwari Mathivanan

2016-01-01

Background: Visually impaired children are unable to maintain good oral hygiene, as their tactile abilities are often underdeveloped owing to their visual disturbances. Conventional brushing techniques are often poorly comprehended by these children and hence, it was decided to evaluate the effectiveness of audio and audio-tactile methods in improving the oral hygiene of these children. Objective: To evaluate and compare the effectiveness of audio and audio-tactile methods in improving oral h...

Visual outcome after endoscopic third ventriculostomy for hydrocephalus.

Science.gov (United States)

Jung, Ji-Ho; Chai, Yong-Hyun; Jung, Shin; Kim, In-Young; Jang, Woo-Youl; Moon, Kyung-Sub; Kim, Seul-Kee; Chong, Sangjoon; Kim, Seung-Ki; Jung, Tae-Young

2018-02-01

Hydrocephalus-related symptoms are mostly improved after successful endoscopic third ventriculostomy (ETV). However, visual symptoms can be different. This study was focused on visual symptoms. We analyzed the magnetic resonance images (MRI) of the orbit and visual outcomes. From August 2006 to November 2016, 50 patients with hydrocephalus underwent ETV. The male-to-female ratio was 33:17, and the median age was 61 years (range, 5-74 years). There were 18 pediatric and 32 adult patients. Abnormal orbital MRI findings included prominent subarachnoid space around the optic nerves and vertical tortuosity of the optic nerves. We retrospectively analyzed clinical symptoms, causes of hydrocephalus, ETV success score (ETVSS), ETV success rate, ETV complications, orbital MRI findings, and visual impairment score (VIS). The median duration of follow-up was 59 months (range, 3-113 months). The most common symptoms were headache, vomiting, and gait disturbance. Visual symptoms were found in 6 patients (12%). The most common causes of hydrocephalus were posterior fossa tumor in 13 patients, pineal tumor in 12, aqueductal stenosis in 8, thalamic malignant glioma in 7, and tectal glioma in 4. ETVSS was 70 in 3 patients, 80 in 34 patients, and 90 in 13 patients. ETV success rate was 80%. ETVSS 70 showed the trend in short-term survival compared to ETVSS 90 and 80. ETV complications included epidural hematoma requiring operation in one patient, transient hemiparesis in two patients, and infection in two patients. Preoperative abnormal orbital MRI findings were found in 18 patients and postoperative findings in 7 patients. Four of six patients with visual symptoms had abnormal MR findings. Three patients did not show VIS improvement, including two with severe visual symptoms. Patients with severe visual impairment were found to have bad outcomes. The visual symptoms related with increased intracranial pressure should be carefully monitored and controlled to improve outcomes.

Design of disturbances control model at automotive company

Science.gov (United States)

Marie, I. A.; Sari, D. K.; Astuti, P.; Teorema, M.

2017-12-01

The discussion was conducted at PT. XYZ which produces automotive components and motorcycle products. The company produced X123 type cylinder head which is a motor vehicle forming component. The disturbances in the production system has affected the company performance in achieving the target of Key Performance Indicator (KPI). Currently, the determination of the percentage of safety stock of cylinder head products is not in accordance to the control limits set by the company (60% - 80%), and tends to exceed the control limits that cause increasing the inventory wastage in the company. This study aims to identify the production system disturbances that occurs in the production process of manufacturing components of X123 type cylinder head products and design the control model of disturbance to obtain control action and determine the safety stock policy in accordance with the needs of the company. The design stage has been done based on the Disturbance Control Model which already existing and customized with the company need in controlling the production system disturbances at the company. The design of the disturbances control model consists of sub-model of the risk level of the disturbance, sub-model of action status, sub-model action control of the disturbance, and sub-model of determining the safety stock. The model can assist the automotive company in taking the decision to perform the disturbances control action in production system cylinder head while controlling the percentage of the safety stock.

Characterizing sleeping habits and disturbances among Saudi adults.

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Al-Tannir, Mohamad; Kobrosly, Samer Y; Al-Badr, Ahmad H; Salloum, Nourhan A; Altannir, Youssef M

2016-12-01

To characterize sleeping habits, assess sleep disturbance prevalence, and identify associated factors among Saudi adults.  Methods: A total of 1720 adults were approached for this observational cross-sectional study between October 2014 and March 2015. The study took place in Riyadh, the capital of Saudi Arabia. We used a questionnaire to describe sleeping characteristics in relation to existing chronic diseases, smoking status, obesity, daily performance and sociodemographic variables. Results: The response rate was 79.6% (1369 participants), 61.6% have or may have sleeping disturbances of which 18.6% claimed either slowed or stopped breathing during sleep. Women reported a higher prevalence of sleep disturbances (65.2%). Feeling tired was significantly associated with sleep disturbance (49% versus 19.7%) (p greater than 0.001). Approximately 78.4% of those with sleep disturbance significantly believed that their ability to perform daily tasks is affected (p=0.005). Moreover, smoking and obesity were significantly associated with sleep disturbances (p less than 0.01). Participants with asthma, hypertension, chronic heart disease, and diabetes mellitus reported significantly more sleeping disturbance (p=0.016 to p=0.001). Conclusions: Sleep disturbances are associated with obesity, smoking, chronic health conditions, and lower performance among  Saudi adults.

Interaction of historical and nonhistorical disturbances maintains native plant communities.

Science.gov (United States)

Davies, K W; Svejcar, T J; Bates, J D

2009-09-01

Historical disturbance regimes are often considered a critical element in maintaining native plant communities. However, the response of plant communities to disturbance may be fundamentally altered as a consequence of invasive plants, climate change, or prior disturbances. The appropriateness of historical disturbance patterns under modern conditions and the interactions among disturbances are issues that ecologists must address to protect and restore native plant communities. We evaluated the response of Artemisia tridentata ssp. wyomingensis (Beetle & A. Young) S.L. Welsh plant communities to their historical disturbance regime compared to other disturbance regimes. The historical disturbance regime of these plant communities was periodic fires with minimal grazing by large herbivores. We also investigated the influence of prior disturbance (grazing) on the response of these communities to subsequent disturbance (burning). Treatments were: (1) ungrazed (livestock grazing excluded since 1936) and unburned, (2) grazed and unburned, (3) ungrazed and burned (burned in 1993), and (4) grazed and burned. The ungrazed-burned treatment emulated the historical disturbance regime. Vegetation cover, density, and biomass production were measured the 12th, 13th, and 14th year post-burning. Prior to burning the presence of Bromus tectorum L., an exotic annual grass, was minimal (resilience to more severe disturbances. Modern deviations from historical conditions can alter ecosystem response to disturbances, thus restoring the historical disturbance regime may not be an appropriate strategy for all ecosystems.

300 Area Disturbance Report

Energy Technology Data Exchange (ETDEWEB)

LL Hale; MK Wright; NA Cadoret

1999-01-07

The objective of this study was to define areas of previous disturbance in the 300 Area of the U.S. Department of Energy (DOE) Hanford Site to eliminate these areas from the cultural resource review process, reduce cultural resource monitoring costs, and allow cultural resource specialists to focus on areas where subsurface disturbance is minimal or nonexistent. Research into available sources suggests that impacts from excavations have been significant wherever the following construction activities have occurred: building basements and pits, waste ponds, burial grounds, trenches, installation of subsurface pipelines, power poles, water hydrants, and well construction. Beyond the areas just mentioned, substrates in the' 300 Area consist of a complex, multidimen- sional mosaic composed of undisturbed stratigraphy, backfill, and disturbed sediments; Four Geographic Information System (GIS) maps were created to display known areas of disturbance in the 300 Area. These maps contain information gleaned from a variety of sources, but the primary sources include the Hanford GIS database system, engineer drawings, and historic maps. In addition to these maps, several assumptions can be made about areas of disturbance in the 300 Area as a result of this study: o o Buried pipelines are not always located where they are mapped. As a result, cultural resource monitors or specialists should not depend on maps depicting subsurface pipelines for accurate locations of previous disturbance. Temporary roads built in the early 1940s were placed on layers of sand and gravel 8 to 12 in. thick. Given this information, it is likely that substrates beneath these early roads are only minimally disturbed. Building foundations ranged from concrete slabs no more than 6 to 8 in. thick to deeply excavated pits and basements. Buildings constructed with slab foundations are more numerous than may be expected, and minimally disturbed substrates may be expected in these locations. Historic

Implicit and explicit self-esteem discrepancies in people with psychogenic nonepileptic seizures.

Science.gov (United States)

Dimaro, Lian V; Roberts, Nicole A; Moghaddam, Nima G; Dawson, David L; Brown, Ian; Reuber, Markus

2015-05-01

Self-esteem (SE), or one's sense of competence and worth, is reduced in many mental and physical disorders. Low SE is associated with perceived stigma and disability and poor treatment outcomes. The present study examined implicit and explicit SE (automatic and deliberate views about the self) in people with epilepsy and people with psychogenic nonepileptic seizures (PNESs). Discrepancies between implicit SE and explicit SE have been found to correlate with psychological distress in disorders often associated with PNESs but are relatively unexplored in PNESs. We hypothesized that, compared with epilepsy, PNESs would be associated with lower self-reported SE and greater discrepancies between implicit SE and explicit SE. Thirty adults with PNESs, 25 adults with epilepsy, and 31 controls without a history of seizures were asked to complete the Rosenberg Self-esteem Scale as a measure of explicit SE and an Implicit Relational Assessment Procedure as a measure of implicit SE. The State-Trait Anxiety Inventory and Patient Health Questionnaire-15 (a somatic symptom inventory) were also administered. We found significant group differences in explicit (p<0.001) but not implicit SE. Patients with PNESs reported lower SE than the other groups. No group differences were found in implicit SE. Implicit-explicit SE discrepancies were larger in the group with PNESs than in the other groups (p<0.001). Higher frequency of PNESs (but not epileptic seizures) was associated with lower explicit SE (rs=-.83, p<0.01) and greater SE discrepancies (i.e., lower explicit relative to implicit SE; rs=.65, p<0.01). These relationships remained significant when controlling for anxiety and somatization. Patients with PNESs had lower explicit SE than those with epilepsy or healthy controls. In keeping with our expectations, there were greater discrepancies between implicit SE and explicit SE among patients with PNESs than in the other groups. Our results, including the strong relationship between

Implications of advanced warning messages on eliminating sun glare disturbances at signalized intersections

Directory of Open Access Journals (Sweden)

Qing Li

2016-08-01

Full Text Available Due to sun glare disturbances, drivers encounter fatal threats on roadways, particularly at signalized intersections. Many studies have attempted to develop applicable solutions, such as avoiding sun positions, applying road geometric re-directions, and wearing anti-glare glasses. None of these strategies have fully solved the problem. As one of the “Connected Vehicle” practices proposed by the U.S. Department of Transportation, advanced warning messages (AWMs are capable of providing wireless information about traffic controls. AWM acts as a supplement to conventional signs and signals, which can be blocked by obstacles or natural disturbances, such as sun glare. The drivers' smart advisory system (DSAS can provide drivers with AWM. Using a driving simulator this research explores the effects of DSAS messages on driving behaviors under sun glare disturbance. Statistical analyses were applied to assess (1 the negative impacts of sun glare, (2 the compensation of the DSAS AWM to sun glare effects, and (3 the improvement in driving performance due to DSAS AWM. Four performance indexes were measured, including (1 half kinetic energy speed, (2 mean approach speed, (3 brake response time, and (4 braking distance. The effects of the socio-demographic factors, such as gender, age, educational background, and driving experience were also studied. The analytical results illustrate that the DSAS can compensate for reduced visibility due to sun glare and improve driving performance to a normal visual situation, particularly for left turn and through movement.

The reciprocal associations between identity disturbance, relationship disturbance, and suicidal ideation among Chinese adolescents: A three-wave cross-lag study.

Science.gov (United States)

Ren, Yaxuan; Zhang, Xu; You, Jianing; Jiang, Yongqiang; Lin, Min-Pei; Leung, Freedom

2017-12-18

Adolescence is a developmental period associated with a heightened risk for suicidal ideation. During this phase of life, individuals tend to focus on both intrapersonal self and interpersonal relationships. Thus, it is of much significance to understand the roles of intrapersonal and interpersonal factors in the development of suicidal ideation among adolescents. The present study examined the reciprocal associations between identity disturbance, relationship disturbance, and suicidal ideation by using a three-wave cross-lag model in a sample of adolescents. A number of 3,600 Chinese adolescents (56.6% females, mean age = 14.58 years) completed questionnaires assessing the three main study variables as well as depressive symptoms, anxiety, and suicidal attempts three times at 6-month intervals. After controlling for gender, age, depressive symptoms, anxiety, and suicidal attempts, relationship disturbance significantly predicted suicidal ideation over time, and vice versa. Suicidal ideation significantly predicted identity disturbance over time, but not vice versa. We also found the mediating effect of relationship disturbance in the path from identity disturbance to suicidal ideation. The results suggested the important role of previous relationship disturbance in predicting later suicidal ideation. Theoretical and clinical implications of these findings were discussed. © 2017 Wiley Periodicals, Inc.

Depression Disturbs Germany

Institute of Scientific and Technical Information of China (English)

2011-01-01

The suicide of Robert Enke,the goalkeeper of the Germany national football team who had battled depression for years,stunned the country and cast depression into the national spotlight as a disturbing disease.

Visual Vection does not Perturb Squatting Posture

Directory of Open Access Journals (Sweden)

Dietrich Gilles

2011-12-01

Full Text Available Vision contributes fundamentally to the control of the standing posture. The illusion of self motion falsely perceived (vection increases postural sway while standing. In this paper we examine the effect of vection on both standing and deep squatting with the hypothesis that the squatting posture should not be disturbed by the conflict of sensory information due to vection. The results show that standing posture only was affected by the visual stimuli. The widespread use of squatting for work as well as rest could be due in part to this lack of effect of sensory perturbation on postural stability.

The role of recurrent disturbances for ecosystem multifunctionality.

Science.gov (United States)

Villnäs, Anna; Norkko, Joanna; Hietanen, Susanna; Josefson, Alf B; Lukkari, Kaarina; Norkko, Alf

2013-10-01

Ecosystem functioning is threatened by an increasing number of anthropogenic stressors, creating a legacy of disturbance that undermines ecosystem resilience. However, few empirical studies have assessed to what extent an ecosystem can tolerate repeated disturbances and sustain its multiple functions. By inducing increasingly recurring hypoxic disturbances to a sedimentary ecosystem, we show that the majority of individual ecosystem functions experience gradual degradation patterns in response to repetitive pulse disturbances. The degradation in overall ecosystem functioning was, however, evident at an earlier stage than for single ecosystem functions and was induced after a short pulse of hypoxia (i.e., three days), which likely reduced ecosystem resistance to further hypoxic perturbations. The increasing number of repeated pulse disturbances gradually moved the system closer to a press response. In addition to the disturbance regime, the changes in benthic trait composition as well as habitat heterogeneity were important for explaining the variability in overall ecosystem functioning. Our results suggest that disturbance-induced responses across multiple ecosystem functions can serve as a warning signal for losses of the adaptive capacity of an ecosystem, and might at an early stage provide information to managers and policy makers when remediation efforts should be initiated.

Forest Disturbance Mapping Using Dense Synthetic Landsat/MODIS Time-Series and Permutation-Based Disturbance Index Detection

Directory of Open Access Journals (Sweden)

David Frantz

2016-03-01

Full Text Available Spatio-temporal information on process-based forest loss is essential for a wide range of applications. Despite remote sensing being the only feasible means of monitoring forest change at regional or greater scales, there is no retrospectively available remote sensor that meets the demand of monitoring forests with the required spatial detail and guaranteed high temporal frequency. As an alternative, we employed the Spatial and Temporal Adaptive Reflectance Fusion Model (STARFM to produce a dense synthetic time series by fusing Landsat and Moderate Resolution Imaging Spectroradiometer (MODIS nadir Bidirectional Reflectance Distribution Function (BRDF adjusted reflectance. Forest loss was detected by applying a multi-temporal disturbance detection approach implementing a Disturbance Index-based detection strategy. The detection thresholds were permutated with random numbers for the normal distribution in order to generate a multi-dimensional threshold confidence area. As a result, a more robust parameterization and a spatially more coherent detection could be achieved. (i The original Landsat time series; (ii synthetic time series; and a (iii combined hybrid approach were used to identify the timing and extent of disturbances. The identified clearings in the Landsat detection were verified using an annual woodland clearing dataset from Queensland’s Statewide Landcover and Trees Study. Disturbances caused by stand-replacing events were successfully identified. The increased temporal resolution of the synthetic time series indicated promising additional information on disturbance timing. The results of the hybrid detection unified the benefits of both approaches, i.e., the spatial quality and general accuracy of the Landsat detection and the increased temporal information of synthetic time series. Results indicated that a temporal improvement in the detection of the disturbance date could be achieved relative to the irregularly spaced Landsat

Changes in Soil Fungal Community Structure with Increasing Disturbance Frequency.

Science.gov (United States)

Cho, Hyunjun; Kim, Mincheol; Tripathi, Binu; Adams, Jonathan

2017-07-01

Although disturbance is thought to be important in many ecological processes, responses of fungal communities to soil disturbance have been little studied experimentally. We subjected a soil microcosm to physical disturbance, at a range of frequencies designed to simulate ecological disturbance events. We analyzed the fungal community structure using Illumina HiSeq sequencing of the ITS1 region. Fungal diversity was found to decline with the increasing disturbance frequencies, with no sign of the "humpback" pattern found in many studies of larger sedentary organisms. There is thus no evidence of an effect of release from competition resulting from moderate disturbance-which suggests that competition and niche overlap may not be important in limiting soil fungal diversity. Changing disturbance frequency also led to consistent differences in community composition. There were clear differences in OTU-level composition, with different disturbance treatments each having distinct fungal communities. The functional profile of fungal groups (guilds) was changed by the level of disturbance frequency. These predictable differences in community composition suggest that soil fungi can possess different niches in relation to disturbance frequency, or time since last disturbance. Fungi appear to be most abundant relative to bacteria at intermediate disturbance frequencies, on the time scale we studied here.

Assessment of sleep disturbance in lung cancer patients: relationship between sleep disturbance and pain, fatigue, quality of life, and psychological distress.

Science.gov (United States)

Nishiura, Mare; Tamura, Atsuhisa; Nagai, Hideaki; Matsushima, Eisuke

2015-06-01

We investigated the prevalence of sleep disturbance and psychological distress in lung cancer patients. We also examined the association between sleep disturbance and psychological distress, pain, fatigue, and quality of life in the same population. Fifty lung cancer patients were evaluated. Sleep disturbance was assessed using the Athens Sleep Insomnia Scale (AIS) and psychological distress using the Hospital Anxiety and Depression Scale (HADS). Quality of life (QOL), pain, and fatigue were assessed employing the European Organization of Research and Treatment Quality of Life Questionnaire-Cancer 30 (EORTC QLQ-C30). We observed that 56% of lung cancer patients had sleep disturbance (AIS score ≥6) and 60% had psychological distress (total HADS score ≥11). Patients with sleep disturbance had a HADS score of 14.6 ± 5.8, a fatigue score of 45.3 ± 22.0, and a pain score of 27.2 ± 26.2. In contrast, patients without sleep disturbance had a lower HADS score of 9.9 ± 8.1 (p psychological distress. Additionally, the type of sleep disturbance was related to other patient factors, including whether or not they received chemotherapy.

The Dimensionality of Body Image Disturbance.

Science.gov (United States)

Galgan, Richard J.; And Others

1987-01-01

Examined personality variables in 75 male and 75 female college students. Found two dimensions underlying body image disturbance variables, one loading on body image dissatisfaction and one loading on body image disturbance. Low negative correlation between two factors suggests that distortion and dissatisfaction are fairly distinct and that body…

An Industrial Model Based Disturbance Feedback Control Scheme

DEFF Research Database (Denmark)

Kawai, Fukiko; Nakazawa, Chikashi; Vinther, Kasper

2014-01-01

This paper presents a model based disturbance feedback control scheme. Industrial process systems have been traditionally controlled by using relay and PID controller. However these controllers are affected by disturbances and model errors and these effects degrade control performance. The authors...... propose a new control method that can decrease the negative impact of disturbance and model errors. The control method is motivated by industrial practice by Fuji Electric. Simulation tests are examined with a conventional PID controller and the disturbance feedback control. The simulation results...

Age structure and disturbance legacy of North American forests

Science.gov (United States)

Y. Pan; J.M. Chen; R. Birdsey; K. McCullough; L. He; F. Deng

2011-01-01

Most forests of the world are recovering from a past disturbance. It is well known that forest disturbances profoundly affect carbon stocks and fluxes in forest ecosystems, yet it has been a great challenge to assess disturbance impacts in estimates of forest carbon budgets. Net sequestration or loss of CO2 by forests after disturbance follows a...

Persistent Visual Aura following Catheter Ablation in a Patient with WPW Syndrome

Directory of Open Access Journals (Sweden)

Shinichi Koyama

2007-01-01

Full Text Available We report a patient who has had persistent visual disturbances since she underwent catheter ablation to treat her Wolff-Parkinson-White (WPW syndrome. We examined her visual symptoms carefully and quantitatively by means of our newly developed method combining image-processing and psychophysics. We first simulated the patient’s visual symptoms using image-processing techniques. Since the simulation indicated that she would be very sensitive to the edges of the visual stimuli, we evaluated her sensitivity to the edges using psychophysics. The results indicated that she was hypersensitive to the clear-cut edges of the visual stimuli. Her visual symptoms were very similar to those of visual aura of migraine, rather than those of photosensitive epilepsy. Magnetic resonance imaging (MRI and single photon emission computed tomography (SPECT, electroenchepalogram (EEG, and visual-evoked potentials (VEP in the patient were normal. No abnormalities in her fundus, visual field, or electroretinogram were found, either. Transesophageal echocardiography with bubble study indicated that she had a preexisting right-to-left shunt. We hypothesize that visual aura of migraine was triggered and made persistent by the catheter ablation in this patient. Although the relationship between migraine, catheter ablation, and right-to-left shunts is unknown, previous studies on the transcatheter closure of patent foramen ovale suggest a possible link between them. Catheter ablation in patients with migraine and preexisting shunts may lead to exacerbations in migraine symptoms.

Language disturbances from mesencephalo-thalamic infarcts

International Nuclear Information System (INIS)

Lazzarino, L.G.; Nicolai, A.; Valassi, F.; Biasizzo, E.

1991-01-01

The authors report the cases of two patients with CT-documented paramedian mesencephalo-thalamic infarcts, showing language disturbances. The first patient showed a non fluent, transcortical motor-like aphasia, the other had a fluent but severely paraphasic language disorder. The CT study disclosed that it was the dorso-median thalamic nucleus that was mostly involved in both cases. These findings agree with a few previous pathological studies suggesting that the paramedian thalamic nuclei, particlularly the dorso-median nucleus may play some role in language disturbances. However the anatomical basis for thalamic aphasia remains speculative, taking into account the importantce of cortical connections in the origin of subcortical neuropsychological disturbances. (orig.)

Predictors of health-related quality of life in patients with epilepsy and psychogenic nonepileptic seizures.

Science.gov (United States)

Rawlings, Gregg H; Brown, Ian; Reuber, Markus

2017-03-01

Epilepsy and psychogenic nonepileptic seizures (PNES) are associated with reduced health-related quality of life (HRQoL). The present study investigated the profile, relationship, and predictive power of illness perceptions, psychological distress (depression and anxiety), seizure activity, and demographic factors on HRQoL in these patient groups. Patients with epilepsy (n=62) and PNES (n=45) were recruited from a United Kingdom hospital and from membership-led organizations for individuals living with seizures. Patients completed a series of self-report questionnaires assessing: anxiety (GAD-7), depression (NDDI-E), illness perceptions (B-IPQ), HRQoL (NEWQOL-6D), and seizure frequency and severity (LSSS-3). Correlational and hierarchical multiple regression analyses were conducted. Patients with epilepsy reported higher HRQoL and scored lower on measures of depression and anxiety. Patients with PNES perceived their condition as more threatening overall. In both conditions, HRQoL was negatively correlated with more severe illness perceptions and psychological distress. In epilepsy and PNES, psychological distress (epilepsy: 27%; PNES: 24.8%) and illness perceptions (epilepsy: 23.1%; PNES: 23.3%) accounted for the largest amount of variance in HRQoL. Clinical factors were found not to be significant predictors, while demographic factors predicted HRQoL in epilepsy (12.6%), but not in PNES. Our findings support the notion that psychological factors are a stronger predictor of HRQoL in epilepsy and PNES than condition-related and demographic variables. Prior research suggests that anxiety and depression are key predictors of HRQoL; this study demonstrates that the relationship between illness perceptions and HRQoL is similarly close. These findings highlight the importance of addressing patients' beliefs about their condition. Copyright © 2016 Elsevier Inc. All rights reserved.

Development of a Scale To Assess Emotional Disturbance.

Science.gov (United States)

Epstein, Michael H.; Cullinan, Douglas; Ryser, Gail; Pearson, Nils

2002-01-01

This study reports on the standardization of the Scale for Assessing Emotional Disturbance. Data collected on 2,266 typical students (ages 5- 18) and 1,371 students with emotional disturbances led to the identification of six behavioral problem factors that correspond to the federal definition of emotional disturbance and were highly internally…

Active disturbance rejection controller for chemical reactor

International Nuclear Information System (INIS)

Both, Roxana; Dulf, Eva H.; Muresan, Cristina I.

2015-01-01

In the petrochemical industry, the synthesis of 2 ethyl-hexanol-oxo-alcohols (plasticizers alcohol) is of high importance, being achieved through hydrogenation of 2 ethyl-hexenal inside catalytic trickle bed three-phase reactors. For this type of processes the use of advanced control strategies is suitable due to their nonlinear behavior and extreme sensitivity to load changes and other disturbances. Due to the complexity of the mathematical model an approach was to use a simple linear model of the process in combination with an advanced control algorithm which takes into account the model uncertainties, the disturbances and command signal limitations like robust control. However the resulting controller is complex, involving cost effective hardware. This paper proposes a simple integer-order control scheme using a linear model of the process, based on active disturbance rejection method. By treating the model dynamics as a common disturbance and actively rejecting it, active disturbance rejection control (ADRC) can achieve the desired response. Simulation results are provided to demonstrate the effectiveness of the proposed method

Active disturbance rejection controller for chemical reactor

Energy Technology Data Exchange (ETDEWEB)

Both, Roxana; Dulf, Eva H.; Muresan, Cristina I., E-mail: roxana.both@aut.utcluj.ro [Technical University of Cluj-Napoca, 400114 Cluj-Napoca (Romania)

2015-03-10

In the petrochemical industry, the synthesis of 2 ethyl-hexanol-oxo-alcohols (plasticizers alcohol) is of high importance, being achieved through hydrogenation of 2 ethyl-hexenal inside catalytic trickle bed three-phase reactors. For this type of processes the use of advanced control strategies is suitable due to their nonlinear behavior and extreme sensitivity to load changes and other disturbances. Due to the complexity of the mathematical model an approach was to use a simple linear model of the process in combination with an advanced control algorithm which takes into account the model uncertainties, the disturbances and command signal limitations like robust control. However the resulting controller is complex, involving cost effective hardware. This paper proposes a simple integer-order control scheme using a linear model of the process, based on active disturbance rejection method. By treating the model dynamics as a common disturbance and actively rejecting it, active disturbance rejection control (ADRC) can achieve the desired response. Simulation results are provided to demonstrate the effectiveness of the proposed method.

Climate change and disturbance interactions: Workshop on climate change and disturbance interactions in western North America, Tucson, Ariz., 12-15 February 2007

Science.gov (United States)

McKenzie, Don; Allen, Craig D.

2007-01-01

Warming temperatures across western North America, coupled with increased drought, are expected to exacerbate disturbance regimes, particularly wildfires, insect outbreaks, and invasions of exotic species. Many ecologists and resource managers expect ecosystems to change more rapidly from disturbance effects than from the effects of a changing climate by itself. A particular challenge is to understand the interactions among disturbance regimes; for example, how will massive outbreaks of bark beetles, which kill drought-stressed trees by feeding on cambial tissues, increase the potential for large severe wildfires in a warming climate?Researchers in climatology, ecosystem science, fire and insect ecology, and landscape modeling from across western North America convened in Tucson, Ariz., for a 2 and a half day intensive workshop to identify new research directions in climate change and disturbance ecology. Four work groups focused on different aspects of the response of disturbance regimes to climate change: (1) extreme events and climatic variability (2) the effects of changing disturbance regimes on ecosystems, (3) disturbance interactions and cumulative effects, and (4) developing new landscape disturbance models. The workshop was structured with the analytic hierarchy process, a decision support method for achieving consensus from diverse groups of experts without sacrificing individual contributions.

Trajectory Control of Scale-Free Dynamical Networks with Exogenous Disturbances

International Nuclear Information System (INIS)

Yang Hongyong; Zhang Shun; Zong Guangdeng

2011-01-01

In this paper, the trajectory control of multi-agent dynamical systems with exogenous disturbances is studied. Suppose multiple agents composing of a scale-free network topology, the performance of rejecting disturbances for the low degree node and high degree node is analyzed. Firstly, the consensus of multi-agent systems without disturbances is studied by designing a pinning control strategy on a part of agents, where this pinning control can bring multiple agents' states to an expected consensus track. Then, the influence of the disturbances is considered by developing disturbance observers, and disturbance observers based control (DOBC) are developed for disturbances generated by an exogenous system to estimate the disturbances. Asymptotical consensus of the multi-agent systems with disturbances under the composite controller can be achieved for scale-free network topology. Finally, by analyzing examples of multi-agent systems with scale-free network topology and exogenous disturbances, the verities of the results are proved. Under the DOBC with the designed parameters, the trajectory convergence of multi-agent systems is researched by pinning two class of the nodes. We have found that it has more stronger robustness to exogenous disturbances for the high degree node pinned than that of the low degree node pinned. (interdisciplinary physics and related areas of science and technology)

(En)Countering Social and Environmental Messages in the Rainforest Cafe [sic], Children's Picturebooks, and Other Visual Culture Sites

Science.gov (United States)

Reisberg, Mira; Han, Sandrine

2009-01-01

Our study critically examines social and environmental messages in a range of visual sites educating about rainforest environments. We focus primarily on the Rainforest Cafe, an international series of rainforest-themed edutainment restaurant/stores, whose inherent contradictions between consumption and conservation are quite disturbing when…

Thermally-Induced Structural Disturbances of Rigid Panel Solar Arrays

Science.gov (United States)

Johnston, John D.; Thornton, Earl A.

1997-01-01

The performance of a significant number of spacecraft has been impacted negatively by attitude disturbances resulting from thermally-induced motions of flexible structures. Recent examples of spacecraft affected by these disturbances include the Hubble Space Telescope (HST) and the Upper Atmosphere Research Satellite (UARS). Thermally-induced structural disturbances occur as the result of rapid changes in thermal loading typically initiated as a satellite exits or enters the Earth's shadow. Temperature differences in flexible appendages give rise to structural deformations, which in turn result in disturbance torques reacting back on the spacecraft. Structures which have proven susceptible to these disturbances include deployable booms and solar arrays. This paper investigates disturbances resulting from thermally-induced deformations of rigid panel solar arrays. An analytical model for the thermal-structural response of the solar array and the corresponding disturbance torque are presented. The effect of these disturbances on the attitude dynamics of a simple spacecraft is then investigated using a coupled system of governing equations which includes the effects of thermally-induced deformations. Numerical results demonstrate the effect of varying solar array geometry on the dynamic response of the system.

Soil disturbance as a grassland restoration measure

DEFF Research Database (Denmark)

Schnoor, Tim; Bruun, Hans Henrik; Olsson, Pål Axel

2015-01-01

Soil disturbance is recognized as an important driver of biodiversity in dry grasslands, and can therefore be implemented as a restoration measure. However, because community re-assembly following disturbance includes stochastic processes, a focus only on species richness or establishment success...... to experimental disturbance treatments (ploughing or rotavation), and the vegetation was surveyed during four subsequent years of succession. Treated plots were compared with control plots representing untreated grassland, as well as nearby plots characterized by plant communities representing the restoration...

Wind Power Prediction Considering Nonlinear Atmospheric Disturbances

Directory of Open Access Journals (Sweden)

Yagang Zhang

2015-01-01

Full Text Available This paper considers the effect of nonlinear atmospheric disturbances on wind power prediction. A Lorenz system is introduced as an atmospheric disturbance model. Three new improved wind forecasting models combined with a Lorenz comprehensive disturbance are put forward in this study. Firstly, we define the form of the Lorenz disturbance variable and the wind speed perturbation formula. Then, different artificial neural network models are used to verify the new idea and obtain better wind speed predictions. Finally we separately use the original and improved wind speed series to predict the related wind power. This proves that the corrected wind speed provides higher precision wind power predictions. This research presents a totally new direction in the wind prediction field and has profound theoretical research value and practical guiding significance.

Trade-off between information and disturbance in qubit thermometry

Science.gov (United States)

Seveso, Luigi; Paris, Matteo G. A.

2018-03-01

We address the trade-off between information and disturbance in qubit thermometry from the perspective of quantum estimation theory. Given a quantum measurement, we quantify information via the Fisher information of the measurement and disturbance via four different figures of merit, which capture different aspects (statistical, thermodynamical, geometrical) of the trade-off. For each disturbance measure, the efficient measurements, i.e., the measurements that introduce a disturbance not greater than any other measurement extracting the same amount of information, are determined explicitly. The family of efficient measurements varies with the choice of the disturbance measure. On the other hand, commutativity between the elements of the probability operator-valued measure (POVM) and the equilibrium state of the thermometer is a necessary condition for efficiency with respect to any figure of disturbance.

Handling process disturbances in petroleum production

Energy Technology Data Exchange (ETDEWEB)

Sten, T; Bodsberg, L; Ingstad, O; Ulleberg, T

1988-06-01

Factors of importance in successful handling of major disturbances and crisis situations in petroleum production are discussed. Case studies based on interviews, questionnaires and systematic observations have been undertaken to identify critical factors in human computer design, in operator competence and attitudes and in work organization. It is shown that certain features of the humancomputer interaction become critical when serious disturbances are encountered. Likewise focusing on requirements during disturbances in particular has highlighted some new aspects of operator competence and of the work organization. The results are considered to be useful input to safety management in petroleum process plants, in formation of design specifications and in identifying need for further research regarding safety in offshore production.

Disturbance phenomena in VLF standard radio wave observation

International Nuclear Information System (INIS)

Muraoka, Yoshikazu

1977-01-01

Storm aftereffect, i.e. the phase disturbance after initiation of a magnetic storm has been revealed in the observation of VLF standard radio waves. In VLF long distance propagation at middle latitudes (L - 3), the phase disturbance for several days after the initiation of a magnetic storm is due to electron fall from the radiation belt. This has been confirmed by the comparison with electron flux detected by an artificial satellite. The correlations between VLF phase disturbance and magnetism activity or ionosphere absorption are described. The relation between winter anomaly and phase disturbance is also discussed. (Mori, K.)

Treatment of sleep disturbances in trauma-affected refugees

DEFF Research Database (Denmark)

Sandahl, Hinuga; Jennum, Poul; Baandrup, Lone

2017-01-01

Background: Sleep disturbances are often referred to as a hallmark and as core symptoms of post-traumatic stress disorder (PTSD). Untreated sleep disturbances can contribute to the maintenance and exacerbation of PTSD symptoms, which may diminish treatment response and constitute a risk factor...... for poor treatment outcome. Controlled trials on treatment of sleep disturbances in refugees suffering from PTSD are scarce. The present study aims to examine sleep-enhancing treatment in refugees with PTSD. We aim to assess if add-on treatment with mianserin and/or Imagery Rehearsal Therapy (IRT......) to treatment as usual (TAU) for PTSD improves sleep disturbances. We will study the relation between sleep disturbances, PTSD symptoms, psychosocial functioning and quality of life. Methods: The study is a randomised controlled superiority trial with a 2 × 2 factorial design. The study will include 230 trauma...

Long-term Correction in Sleep Disturbance Is Sustained After Arthroscopic Rotator Cuff Repair.

Science.gov (United States)

Horneff, John G; Tjoumakaris, Fotios; Wowkanech, Charles; Pepe, Matthew; Tucker, Bradford; Austin, Luke

2017-06-01

Sleep disturbance is a major complaint of patients with rotator cuff disease that often leads them to seek treatment. The authors previously reported a prospective analysis of patients who underwent rotator cuff repair and found that sleep disturbance significantly improved at 3 months after surgery. That improvement in sleep was maintained at 6 months. In the current study, the authors sought to gain medium-term data on this same population at greater than 2 years. The hypotheses were that improvement in sleep disturbance after arthroscopic rotator cuff repair is maintained at 2-year follow-up and that the continued use of narcotic pain medication has a negative effect on sleep quality at 2-year follow-up. Case series; Level of evidence, 4. The original cohort of patients was contacted at a minimum of 24 months after their surgery. Thirty-seven of the 56 patients (66%) involved in the original study were available. Patient outcomes were scored using the Pittsburgh Sleep Quality Index (PSQI), Simple Shoulder Test (SST), visual analog scale (VAS) for pain, and Single Assessment Numeric Evaluation (SANE). The newly obtained scores were compared with prior scores, which ranged from preoperatively to 6 months postoperatively. The statistically significant improvement of the PSQI score demonstrated in our prior analysis at 6 months postoperatively was maintained, with a mean PSQI score of 5.5 for the 37 patients followed beyond 24 months. Of those patients, 41% still had a PSQI score >5, indicative of sleep disturbance. However, even those patients in our study with a PSQI score >5, indicative of sleep disturbance, had an improved mean score of 9.3 at greater than 24 months compared with those patients with a PSQI score >5 at 6 months, who had a mean PSQI score of 11.5 ( P = .13). Both the SST and VAS scores displayed continued improvement at greater than 24 months, with both displaying moderate strength correlation to the PSQI score (VAS: Spearman rho = 0.479, P < .001

Clinical and cognitive correlates of visual hallucinations in dementia with Lewy bodies.

Science.gov (United States)

Cagnin, Annachiara; Gnoato, Francesca; Jelcic, Nela; Favaretto, Silvia; Zarantonello, Giulia; Ermani, Mario; Dam, Mauro

2013-05-01

The presence of recurrent complex visual hallucinations (VHs) is a core feature of dementia with Lewy bodies (DLB). The aim of this study was to investigate which clinical and neuropsychological characteristics are associated with VHs and their predictive value over a 1 year follow-up. 81 DLB patients, 41 with (VH+) and 36 without (VH-) VHs, and 45 patients with Alzheimer's disease (AD), were enrolled. All participants underwent extensive neuropsychological testing. Visual-spatial and perceptual abilities were evaluated with the Visual and Object Space Perception (VOSP) battery. Fluctuations in attention, rapid eye movement sleep behaviour disorder (RBD) symptoms, extrapyramidal signs and behavioural disturbances were studied with dedicated clinical scales. The presence of VHs was associated with older age and later disease onset, but not with disease duration or with fluctuations, RBD or parkinsonism severity. Cognitive correlates of VHs were deficits in visual attention (digit cancellation: pspan forward: pVisual-perceptual and visual-spatial deficits were significantly worse in DLB than in AD patients (VOSP subtests scores 1, 6, 7 and 8) but were not different in DLB VH+ and VH-, except for subtest 6. Poor performance in the visual attention task was an independent predictor of VHs. Impairment of visual-spatial and perceptual abilities in DLB represents a disease related cognitive signature, independent of the presence of VHs, for which it may represent a predisposing condition. Visual attention, instead, is the main cognitive determinant for the genesis of VHs.

Sleep disturbance associated factors in menopausal women

Directory of Open Access Journals (Sweden)

Hamid Haghani

2011-09-01

Full Text Available Background: Sleep is necessary in life and approximately 1/3 of human life is devoted to sleep. One of the most common problems in menopausal women is sleep disturbance. The aim of this study was to determine frequency of sleep disorders and its related factors in 50 – 60 years old women Methods: A cross-sectional, descriptive study was conducted on 200 eligible women who referred to selected health centers of Tehran University of Medical Sciences (TUMS. Demographic form, ten-point slide to review sexual satisfaction and Pittsburg Sleep Quality Index Questioner (PSQI were used for data collection. Data was analyzed using ANOVA, t-test, and Pearson correlation tests.Results: The mean age of women was 53.6±3.6 year, menopause age 47.8±4, number of children 4.76±2 and partner age was 57.99±6.6. 34.5% of women were satisfied from their sexual relationship and their score was 8-10. Rate of sleep disturbances in this group was about 70%. The results showed that between four variables: economical status, occupation, partner occupation and educational status were significantly associated with sleep disturbance (P=0.002. There was not significant difference between other demographic information and sleep disturbance.Conclusion: The results show high prevalence of sleep disturbance symptoms among menopausal women. According to the relationship between some personal characters and sleep disturbance, health care providers need to consider these variables.

A meta-analysis of soil microbial biomass responses to forest disturbances

Directory of Open Access Journals (Sweden)

Sandra Robin Holden

2013-06-01

Full Text Available Climate warming is likely to increase the frequency and severity of forest disturbances, with uncertain consequences for soil microbial communities and their contribution to ecosystem C dynamics. To address this uncertainty, we conducted a meta-analysis of 139 published soil microbial responses to forest disturbances. These disturbances included abiotic (fire, harvesting, storm and biotic (insect, pathogen disturbances. We hypothesized that soil microbial biomass would decline following forest disturbances, but that abiotic disturbances would elicit greater reductions in microbial biomass than biotic disturbances. In support of this hypothesis, across all published studies, disturbances reduced soil microbial biomass by an average of 29.4%. However, microbial responses differed between abiotic and biotic disturbances. Microbial responses were significantly negative following fires, harvest, and storms (48.7%, 19.1%, and 41.7% reductions in microbial biomass, respectively. In contrast, changes in soil microbial biomass following insect infestation and pathogen-induced tree mortality were non-significant, although biotic disturbances were poorly represented in the literature. When measured separately, fungal and bacterial responses to disturbances mirrored the response of the microbial community as a whole. Changes in microbial abundance following disturbance were significantly positively correlated with changes in microbial respiration. We propose that the differential effect of abiotic and biotic disturbances on microbial biomass may be attributable to differences in soil disruption and organic C removal from forests among disturbance types. Altogether, these results suggest that abiotic forest disturbances may significantly decrease soil microbial abundance, with corresponding consequences for microbial respiration. Further studies are needed on the effect of biotic disturbances on forest soil microbial communities and soil C dynamics.

Prevalence of sleep disturbance in chronic pain.

Science.gov (United States)

Karaman, S; Karaman, T; Dogru, S; Onder, Y; Citil, R; Bulut, Y E; Tapar, H; Sahin, A; Arici, S; Kaya, Z; Suren, M

2014-01-01

Sleep is a vital function for human beings, which can be affected by several factors. Chronic pain is one of these factors where it is the most frequent cause for seeking medical care in combination with insomnia. The aim of this study is to examine the prevalence and relationship between sleep disturbance and chronic pain. After approval, a total of 85 Family Medicine Units from over 170 in Tokat were randomly selected using a 50% sampling. A sample of 2635 subjects, over the age of 19 years, who were registered with the selected Family Medicine Units, were assessed due to gender, age group, and the urban/rural population size of Tokat using the stratified sampling method. The sample size distribution was calculated as 1515 urban subjects, 1120 rural subjects; 1345 female subjects, 1290 male subjects; 1123 subjects between 20-39 years of age, 1103 subjects between the ages of 40-64, and 409 subjects over 64 years of age. After sampling, subjects were invited to participate in the study via an invitation letter, and agreeing individuals were taken to the Family Medicine Unit for face-to-face meetings. Written, informed consent was obtained, along with demographic data. The presence of chronic pain was recorded. According to the presence of chronic pain, all subjects were separated into two groups as Group Chronic Pain and Group Non-Chronic Pain. The visual analog scale for pain intensity, and Pittsburgh Sleep Quality Index for sleep quality, were performed with all subjects. A multiple linear regression model was used to assess the predictors of sleep quality. Analyses were conducted using the Statistical Package for Social Sciences program (SPSS Inc., Chicago, IL, USA), version 20.0. The statistical significance for all analyses was set at p 5. A moderate positive correlation was found between the global Pittsburgh Sleep Quality Index and Visual Analog Scale scores (r = 0.310, p < 0.01). A multiple linear regression analysis showed that age, gender, income, Visual

Composite Intelligent Learning Control of Strict-Feedback Systems With Disturbance.

Science.gov (United States)

Xu, Bin; Sun, Fuchun

2018-02-01

This paper addresses the dynamic surface control of uncertain nonlinear systems on the basis of composite intelligent learning and disturbance observer in presence of unknown system nonlinearity and time-varying disturbance. The serial-parallel estimation model with intelligent approximation and disturbance estimation is built to obtain the prediction error and in this way the composite law for weights updating is constructed. The nonlinear disturbance observer is developed using intelligent approximation information while the disturbance estimation is guaranteed to converge to a bounded compact set. The highlight is that different from previous work directly toward asymptotic stability, the transparency of the intelligent approximation and disturbance estimation is included in the control scheme. The uniformly ultimate boundedness stability is analyzed via Lyapunov method. Through simulation verification, the composite intelligent learning with disturbance observer can efficiently estimate the effect caused by system nonlinearity and disturbance while the proposed approach obtains better performance with higher accuracy.

Postoperative circadian disturbances

DEFF Research Database (Denmark)

Gögenur, Ismail

2010-01-01

) in urine the first night after both minor and major surgery. This delay after major surgery was correlated to the duration of surgery. The amplitude in the melatonin rhythm was unchanged the first night but increased in the second night after major surgery. The amplitude in AMT6s was reduced the first...... night after minimally invasive surgery. The core body temperature rhythm was disturbed after both major and minor surgery. There was a change in the sleep wake cycle with a significantly increased duration of REM-sleep in the day and evening time after major surgery compared with preoperatively....... There was also a shift in the autonomic nervous balance after major surgery with a significantly increased number of myocardial ischaemic episodes during the nighttime period. The circadian activity rhythm was also disturbed after both minor and major surgery. The daytime AMT6s excretion in urine after major...

MR imaging of the lumber spine; Visualization capability of the nerve root

Energy Technology Data Exchange (ETDEWEB)

Ishibashi, Kazumasa; Hieda, Hiroshi; Goto, Takeshi; Goto, Hiroshi; Koga, Hiromichi; Hiraoka, Kouji (Moji Rousai Hospital, Fukuoka (Japan))

1991-01-01

We studied visualization capability of the nerve root in mainly coronary section pattern using magnetic resonance imaging (MRI). MRI was carried out in 91 patients with lumbago and sciatica. Coronary section was additionally photographed in 58 cases of these patients (32 with intervertebral hernia, 20 with spinal canal stenosis, 2 with spondylolytic spondylolisthesis, 2 with compression fracture and the other 2 patients). The visualization capability of the nerve root was studied with photographing 2 pulse systems of the coronary section by using spin echo and field echo methods. The high signal area of the cerebrospinal fluid and nerve root in the normal lumbar vertebra was noted by field echo method, and pattern that is visualized by myelogram was obtained. The coincidence of the main foci (disturbed lesions of the nerve root) in the intervertebral hernia and coronary section pattern was noted in 21 of 32 cases (64.5%) with considerably high ratio. The condition of the nerve root in the blocked lesion was visualized in the spinal canal stenosis. (author).

MAPPING DISTURBANCE DYNAMICS IN WET SCLEROPHYLL FORESTS USING TIME SERIES LANDSAT

Directory of Open Access Journals (Sweden)

A. Haywood

2016-06-01

Full Text Available In this study, we characterised the temporal-spectral patterns associated with identifying acute-severity disturbances and low-severity disturbances between 1985 and 2011 with the objective to test whether different disturbance agents within these categories can be identified with annual Landsat time series data. We analysed a representative State forest within the Central Highlands which has been exposed to a range of disturbances over the last 30 years, including timber harvesting (clearfell, selective and thinning and fire (wildfire and prescribed burning. We fitted spectral time series models to annual normal burn ratio (NBR and Tasseled Cap Indices (TCI, from which we extracted a range of disturbance and recovery metrics. With these metrics, three hierarchical random forest models were trained to 1 distinguish acute-severity disturbances from low-severity disturbances; 2a attribute the disturbance agents most likely within the acute-severity class; 2b and attribute the disturbance agents most likely within the low-severity class. Disturbance types (acute severity and low-severity were successfully mapped with an overall accuracy of 72.9 %, and the individual disturbance types were successfully attributed with overall accuracies ranging from 53.2 % to 64.3 %. Low-severity disturbance agents were successfully mapped with an overall accuracy of 80.2 %, and individual agents were successfully attributed with overall accuracies ranging from 25.5 % to 95.1. Acute-severity disturbance agents were successfully mapped with an overall accuracy of 95.4 %, and individual agents were successfully attributed with overall accuracies ranging from 94.2 % to 95.2 %. Spectral metrics describing the disturbance magnitude were more important for distinguishing the disturbance agents than the post-disturbance response slope. Spectral changes associated with planned burning disturbances had generally lower magnitudes than selective harvesting

Take a look at the bright side : effects of positive body exposure on visual attention in body dissatisfied women

NARCIS (Netherlands)

Glashouwer, K. A.; Jonker, N.C.; Thomassen, K.; de Jong, P.J.

2014-01-01

Background: Body image disturbance is one of the main diagnostic criteria for eating disorders and is considered an important factor in the onset and maintenance of these disorders. Body dissatisfaction has been linked to dysfunctional selective visual attention towards one's body. In comparison to

The role of recurrent disturbances for ecosystem multifunctionality

OpenAIRE

Villnäs, Anna; Norkko, Joanna; Hietanen, Susanna; Josefson, Alf; Lukkari, Kaarina; Norkko, Alf

2013-01-01

Ecosystem functioning is threatened by an increasing number of anthropogenic stressors, creating a legacy of disturbance that undermines ecosystem resilience. However, few empirical studies have assessed to what extent an ecosystem can tolerate repeated disturbances and sustain its multiple functions. By inducing increasingly recurring hypoxic disturbances to a sedimentary ecosystem, we show that the majority of individual ecosystem functions experience gradual degradation patterns in respons...

Secondary plant succession on disturbed sites at Yucca Mountain, Nevada

Energy Technology Data Exchange (ETDEWEB)

Angerer, J.P.; Ostler, W.K.; Gabbert, W.D.; Schultz, B.W.

1994-12-01

This report presents the results of a study of secondary plant succession on disturbed sites created during initial site investigations in the late 1970s and early 1980s at Yucca Mountain, NV. Specific study objectives were to determine the rate and success of secondary plant succession, identify plant species found in disturbances that may be suitable for site-specific reclamation, and to identify environmental variables that influence succession on disturbed sites. During 1991 and 1992, fifty seven disturbed sites were located. Vegetation parameters, disturbance characteristics and environmental variables were measured at each site. Disturbed site vegetation parameters were compared to that of undisturbed sites to determine the status of disturbed site plant succession. Vegetation on disturbed sites, after an average of ten years, was different from undisturbed areas. Ambrosia dumosa, Chrysothamnus teretifolius, Hymenoclea salsola, Gutierrezia sarothrae, Atriplex confertifolia, Atriplex canescens, and Stephanomeria pauciflora were the most dominant species across all disturbed sites. With the exception of A. dumosa, these species were generally minor components of the undisturbed vegetation. Elevation, soil compaction, soil potassium, and amounts of sand and gravel in the soil were found to be significant environmental variables influencing the species composition and abundance of perennial plants on disturbed sites. The recovery rate for disturbed site secondary succession was estimated. Using a linear function (which would represent optimal conditions), the recovery rate for perennial plant cover, regardless of which species comprised the cover, was estimated to be 20 years. However, when a logarithmic function (which would represent probable conditions) was used, the recovery rate was estimated to be 845 years. Recommendations for future studies and site-specific reclamation of disturbances are presented.

Secondary plant succession on disturbed sites at Yucca Mountain, Nevada

International Nuclear Information System (INIS)

Angerer, J.P.; Ostler, W.K.; Gabbert, W.D.; Schultz, B.W.

1994-12-01

This report presents the results of a study of secondary plant succession on disturbed sites created during initial site investigations in the late 1970s and early 1980s at Yucca Mountain, NV. Specific study objectives were to determine the rate and success of secondary plant succession, identify plant species found in disturbances that may be suitable for site-specific reclamation, and to identify environmental variables that influence succession on disturbed sites. During 1991 and 1992, fifty seven disturbed sites were located. Vegetation parameters, disturbance characteristics and environmental variables were measured at each site. Disturbed site vegetation parameters were compared to that of undisturbed sites to determine the status of disturbed site plant succession. Vegetation on disturbed sites, after an average of ten years, was different from undisturbed areas. Ambrosia dumosa, Chrysothamnus teretifolius, Hymenoclea salsola, Gutierrezia sarothrae, Atriplex confertifolia, Atriplex canescens, and Stephanomeria pauciflora were the most dominant species across all disturbed sites. With the exception of A. dumosa, these species were generally minor components of the undisturbed vegetation. Elevation, soil compaction, soil potassium, and amounts of sand and gravel in the soil were found to be significant environmental variables influencing the species composition and abundance of perennial plants on disturbed sites. The recovery rate for disturbed site secondary succession was estimated. Using a linear function (which would represent optimal conditions), the recovery rate for perennial plant cover, regardless of which species comprised the cover, was estimated to be 20 years. However, when a logarithmic function (which would represent probable conditions) was used, the recovery rate was estimated to be 845 years. Recommendations for future studies and site-specific reclamation of disturbances are presented

Reconstructing disturbances and their biogeochemical consequences over multiple timescales

Science.gov (United States)

McLauchlan, Kendra K.; Higuera, Philip E.; Gavin, Daniel G.; Perakis, Steven S.; Mack, Michelle C.; Alexander, Heather; Battles, John; Biondi, Franco; Buma, Brian; Colombaroli, Daniele; Enders, Sara K.; Engstrom, Daniel R.; Hu, Feng Sheng; Marlon, Jennifer R.; Marshall, John; McGlone, Matt; Morris, Jesse L.; Nave, Lucas E.; Shuman, Bryan; Smithwick, Erica A.H.; Urrego, Dunia H.; Wardle, David A.; Williams, Christopher J.; Williams, Joseph J.

2014-01-01

Ongoing changes in disturbance regimes are predicted to cause acute changes in ecosystem structure and function in the coming decades, but many aspects of these predictions are uncertain. A key challenge is to improve the predictability of postdisturbance biogeochemical trajectories at the ecosystem level. Ecosystem ecologists and paleoecologists have generated complementary data sets about disturbance (type, severity, frequency) and ecosystem response (net primary productivity, nutrient cycling) spanning decadal to millennial timescales. Here, we take the first steps toward a full integration of these data sets by reviewing how disturbances are reconstructed using dendrochronological and sedimentary archives and by summarizing the conceptual frameworks for carbon, nitrogen, and hydrologic responses to disturbances. Key research priorities include further development of paleoecological techniques that reconstruct both disturbances and terrestrial ecosystem dynamics. In addition, mechanistic detail from disturbance experiments, long-term observations, and chronosequences can help increase the understanding of ecosystem resilience.

Age structure and disturbance legacy of North American forests

Directory of Open Access Journals (Sweden)

Y. Pan

2011-03-01

Full Text Available Most forests of the world are recovering from a past disturbance. It is well known that forest disturbances profoundly affect carbon stocks and fluxes in forest ecosystems, yet it has been a great challenge to assess disturbance impacts in estimates of forest carbon budgets. Net sequestration or loss of CO₂ by forests after disturbance follows a predictable pattern with forest recovery. Forest age, which is related to time since disturbance, is a useful surrogate variable for analyses of the impact of disturbance on forest carbon. In this study, we compiled the first continental forest age map of North America by combining forest inventory data, historical fire data, optical satellite data and the dataset from NASA's Landsat Ecosystem Disturbance Adaptive Processing System (LEDAPS project. A companion map of the standard deviations for age estimates was developed for quantifying uncertainty. We discuss the significance of the disturbance legacy from the past, as represented by current forest age structure in different regions of the US and Canada, by analyzing the causes of disturbances from land management and nature over centuries and at various scales. We also show how such information can be used with inventory data for analyzing carbon management opportunities. By combining geographic information about forest age with estimated C dynamics by forest type, it is possible to conduct a simple but powerful analysis of the net CO₂ uptake by forests, and the potential for increasing (or decreasing this rate as a result of direct human intervention in the disturbance/age status. Finally, we describe how the forest age data can be used in large-scale carbon modeling, both for land-based biogeochemistry models and atmosphere-based inversion models, in order to improve the spatial accuracy of carbon cycle simulations.

Disturbance ecology and forest management: A review of the literature

Science.gov (United States)

Paul Rogers

1996-01-01

This review of the disturbance ecology literature, and how it pertains to forest management, is a resource for forest managers and researchers interested in disturbance theory, specific disturbance agents, their interactions, and appropriate methods of inquiry for specific geographic regions. Implications for the future of disturbance ecology-based management are...

Changing Forest Disturbance Regimes and Risk Perceptions in Homer, Alaska

Science.gov (United States)

Courtney G. F1int

2007-01-01

Forest disturbances caused by insects can lead to other disturbances, risks, and changes across landscapes. Evaluating the human dimensions of such disturbances furthers understanding of integrated changes in natural and social systems. This article examines the effects of changing forest disturbance regimes on local risk perceptions and attitudes in Homer, Alaska....

The anatomy of object recognition--visual form agnosia caused by medial occipitotemporal stroke.

Science.gov (United States)

Karnath, Hans-Otto; Rüter, Johannes; Mandler, André; Himmelbach, Marc

2009-05-06

The influential model on visual information processing by Milner and Goodale (1995) has suggested a dissociation between action- and perception-related processing in a dorsal versus ventral stream projection. It was inspired substantially by the observation of a double dissociation of disturbed visual action versus perception in patients with optic ataxia on the one hand and patients with visual form agnosia (VFA) on the other. Unfortunately, almost all cases with VFA reported so far suffered from inhalational intoxication, the majority with carbon monoxide (CO). Since CO induces a diffuse and widespread pattern of neuronal and white matter damage throughout the whole brain, precise conclusions from these patients with VFA on the selective role of ventral stream structures for shape and orientation perception were difficult. Here, we report patient J.S., who demonstrated VFA after a well circumscribed brain lesion due to stroke etiology. Like the famous patient D.F. with VFA after CO intoxication studied by Milner, Goodale, and coworkers (Goodale et al., 1991, 1994; Milner et al., 1991; Servos et al., 1995; Mon-Williams et al., 2001a,b; Wann et al., 2001; Westwood et al., 2002; McIntosh et al., 2004; Schenk and Milner, 2006), J.S. showed an obvious dissociation between disturbed visual perception of shape and orientation information on the one side and preserved visuomotor abilities based on the same information on the other. In both hemispheres, damage primarily affected the fusiform and the lingual gyri as well as the adjacent posterior cingulate gyrus. We conclude that these medial structures of the ventral occipitotemporal cortex are integral for the normal flow of shape and of contour information into the ventral stream system allowing to recognize objects.

Auditory and Visual Memories in PTSD Patients Targeted with Eye Movements and Counting: The Effect of Modality-Specific Loading of Working Memory

Directory of Open Access Journals (Sweden)

Suzy J. M. A. Matthijssen

2017-11-01

Full Text Available Introduction: Eye movement desensitization and reprocessing (EMDR therapy is an evidence-based treatment for post-traumatic stress disorder (PTSD. A key element of this therapy is simultaneously recalling an emotionally disturbing memory and performing a dual task that loads working memory. Memories targeted with this therapy are mainly visual, though there is some evidence that auditory memories can also be targeted.Objective: The present study tested whether auditory memories can be targeted with EMDR in PTSD patients. A second objective was to test whether taxing the patient (performing a dual task while recalling a memory in a modality specific way (auditory demanding for auditory memories and visually demanding for visual memories was more effective in reducing the emotionality experienced than taxing in cross-modality.Methods: Thirty-six patients diagnosed with PTSD were asked to recall two disturbing memories, one mainly visual, the other one mainly auditory. They rated the emotionality of the memories before being exposed to any condition. Both memories were then recalled under three alternating conditions [visual taxation, auditory taxation, and a control condition (CC, which comprised staring a non-moving dot] – counterbalanced in order – and patients rerated emotionality after each condition.Results: All three conditions were equally effective in reducing the emotionality of the auditory memory. Auditory loading was more effective in reducing the emotionality in the visual intrusion than the CC, but did not differ from the visual load.Conclusion: Auditory and visual aversive memories were less emotional after working memory taxation (WMT. This has some clinical implications for EMDR therapy, where mainly visual intrusions are targeted. In this study, there was no benefit of modality specificity. Further fundamental research should be conducted to specify the best protocol for WMT.

Auditory and Visual Memories in PTSD Patients Targeted with Eye Movements and Counting: The Effect of Modality-Specific Loading of Working Memory.

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Matthijssen, Suzy J M A; Verhoeven, Liselotte C M; van den Hout, Marcel A; Heitland, Ivo

2017-01-01

Introduction: Eye movement desensitization and reprocessing (EMDR) therapy is an evidence-based treatment for post-traumatic stress disorder (PTSD). A key element of this therapy is simultaneously recalling an emotionally disturbing memory and performing a dual task that loads working memory. Memories targeted with this therapy are mainly visual, though there is some evidence that auditory memories can also be targeted. Objective: The present study tested whether auditory memories can be targeted with EMDR in PTSD patients. A second objective was to test whether taxing the patient (performing a dual task while recalling a memory) in a modality specific way (auditory demanding for auditory memories and visually demanding for visual memories) was more effective in reducing the emotionality experienced than taxing in cross-modality. Methods: Thirty-six patients diagnosed with PTSD were asked to recall two disturbing memories, one mainly visual, the other one mainly auditory. They rated the emotionality of the memories before being exposed to any condition. Both memories were then recalled under three alternating conditions [visual taxation, auditory taxation, and a control condition (CC), which comprised staring a non-moving dot] - counterbalanced in order - and patients rerated emotionality after each condition. Results: All three conditions were equally effective in reducing the emotionality of the auditory memory. Auditory loading was more effective in reducing the emotionality in the visual intrusion than the CC, but did not differ from the visual load. Conclusion: Auditory and visual aversive memories were less emotional after working memory taxation (WMT). This has some clinical implications for EMDR therapy, where mainly visual intrusions are targeted. In this study, there was no benefit of modality specificity. Further fundamental research should be conducted to specify the best protocol for WMT.

Gastrointestinal disturbances in marathon runners.

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Riddoch, C; Trinick, T

1988-06-01

The purpose of this survey was to investigate the prevalence of running-induced gastrointestinal (GI) disturbances in marathon runners. A questionnaire was completed by 471 of the estimated 1,750 competitors in the 1986 Belfast City Marathon. Eighty-three per cent of respondents indicated that they occasionally or frequently suffered one or more GI disturbances during or immediately after running. The urge to have a bowel movement (53%) and diarrhoea (38%) were the most common symptoms, especially among female runners (74% and 68% respectively). Upper GI tract symptoms were experienced more by women than men (p less than 0.05) and more by younger runners than older runners (p less than 0.01). Women also suffered more lower GI tract symptoms than men (p less than 0.05) with younger runners showing a similar trend. Both upper and lower tract symptoms were more common during a "hard" run than an "easy" run (p less than 0.01) and were equally as common both during and after running. Of those runners who suffered GI disturbances, 72% thought that running was the cause and 29% believed their performance to be adversely affected. There was no consensus among sufferers as to the causes of symptoms and a wide variety of "remedies" were suggested. GI disturbances are common amongst long-distance runners and their aetiology is unknown. Medical practitioners should be aware of this when dealing with patients who run.

Characteristics of Sleep Disturbances in Patients with Gastroesophageal Reflux Disease.

Science.gov (United States)

Iwakura, Narika; Fujiwara, Yasuhiro; Shiba, Masatsugu; Ochi, Masahiro; Fukuda, Takashi; Tanigawa, Tetsuya; Yamagami, Hirokazu; Tominaga, Kazunari; Watanabe, Toshio; Arakawa, Tetsuo

2016-01-01

Objective Gastroesophageal reflux disease (GERD) is strongly associated with sleep disturbances; however, the detailed differences in the characteristics of sleep disturbances between GERD and non-GERD patients are unknown. The aim of the present study was to analyze the clinical characteristics as well as health-related quality of life in GERD and non-GERD patients with sleep disturbances. Methods Three hundred and fifty patients, including 124 patients with GERD and 226 patients without GERD, completed a self-administered questionnaire that evaluated clinical information. The Pittsburg Sleep Quality Index (PSQI), Hospital Anxiety and Depression Scale (HADS), Insomnia Severity Index (ISI), Epworth Sleepiness Scale (ESS) and 8-item Short-Form Health Survey (SF-8) were also used. Sleep disturbance was considered to be present if the PSQI was >5.5. Results The prevalence of sleep disturbances was significantly higher in the GERD patients (66/124, 53.9%) than in the non-GERD patients (89/226, 39.3%). Depression and anxiety were significantly more common in the subjects with sleep disturbances than in those without sleep disturbances, although there were no differences between the GERD and non-GERD patients. Among the subjects with sleep disturbances, daytime sleepiness was more common in the GERD patients than in the non-GERD patients. The subjects with sleep disturbances had a poorer health-related quality of life. The physical components of quality of life were impaired, particularly in the GERD patients with sleep disturbances. Conclusion GERD patients with sleep disturbances commonly experience daytime sleepiness and an impaired health-related quality of life, especially in terms of physical components.

Disturbance and distributions: avoiding exclusion in a warming world

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Douglas Sheil

2016-03-01

Full Text Available I highlight how disturbance determines species distributions and the implications for conservation practice. In particular, I describe opportunities to mitigate some of the threats to species resulting from climate change. Ecological theory shows that disturbance processes can often slow or prevent the exclusion of species by competitors and that different disturbance regimes result in different realized niches. There is much evidence of disturbance influencing where species occur. For example, disturbance can lower the high elevation treeline, thus expanding the area for high elevation vegetation that cannot otherwise persist under tree cover. The role of disturbance in influencing interspecific competition and resulting species persistence and distributions appears unjustly neglected. I identify various implications, including opportunities to achieve in situ conservation by expanding plant species ranges and reducing species vulnerability to competitive exclusion. Suitable frequencies, scales, intensities, spatial configurations, and timings of the right forms of disturbance can improve the persistence of targeted species in a wide range of contexts. Such options could reduce the extinctions likely to be associated with climate change. More generally, these mechanisms and the resulting realizable niche also offer novel insights to understanding and manipulating species distributions.

[The contribution of systems theory and "existential integrative psychotherapy" to the relationship of the concepts "endogenous", "exogenous", "psychogenic", and "sociogenic" in psychic disorders].

Science.gov (United States)

Bühler, K E; Wyss, D

1980-01-01

Proof is given that the "atomistic" concepts of sickness lead to insolvable contradictions of methodic and logic origin. In this study these contradictions are exemplified and critically analysed, and historical aspects are included. We then propose the dimensions "Interior--Exterior" and "Psychogenous--Somatogeneous" as an heuristic model, dimensions on which any sickness is to be located according to its basic causes. The General System Theory had developed a new formal concept of sickness based on a relatively complete and integral vision of the human being. Nevertheless, the constructs of the General System Theory remain incomplete as they include only objects and their relations, never individual subjects. Wyss however has established explicitely an anthropology of the subject which he connects with his communication orientated concept of sickness. This concept does not judge sickness to be contradictory to health, but both, sickness and health together, form a functional whole on a higher level of abstraction. On this level the organism and its functions, the "interior", represent an inherent component of the "exterior". "Interior" and "exterior"--differentiated in various items--attempt to establish an equilibrium that is always in danger of being desquilibrized.

Impulsive Flocking of Dynamical Multiagent Systems with External Disturbances

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Fujun Han

2017-01-01

Full Text Available Flocking motion of multiagent systems is influenced by various external disturbances in complex environment. By applying disturbance observer, flocking of multiagent systems with exogenous disturbances is studied. Based on the robust features of impulsive control, a distributed impulsive control protocol is presented with disturbance observer, and flocking motion of multiagent systems is analyzed. Moreover, a sufficient condition is obtained to ensure the flocking motion of multiagent systems following a leader. Finally, simulation results show the validity of the theoretical conclusion.

Body image disturbance and skin bleaching.

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Charles, Christopher A D; McLean, Shua-Kym

2017-11-01

This study looks at body image disturbance among Jamaicans who bleach their skin. The hypothesis states that there is a positive relationship between skin bleaching and body image disturbance. The study used a convenience sample of 160 participants with a skin bleaching group (n = 80) and a non-bleaching comparison group (n = 80). The instrument included demographic questions, the body image disturbance questionnaire (BIDQ), and questions about skin bleaching. The results of a t-test revealed that the skin bleaching group (M = 1.5255, SD = 0.42169) was not significantly different from the non-bleaching group (M = 1.4938, SD = 0.74217) in terms of body image disturbance, t(158) = 0.333, p = .740. The participants who bleached did not suffer from body image disturbance. Self-reports revealed that they bleached to acquire beauty, attract a partner, elude the police, and market skin bleaching products. The practice was fashionable and popular and it made some participants feel good, while others were fans of a popular musical artiste who bleached his skin. The majority of participants bleached because of the perceived personal, social, and entrepreneurial benefits of the practice and not because they suffered emotional distress, anxiety, and functional impairment because of their skin colour. However, there was some level of BID among the minority of participants who argued that they bleached because they wanted to be pretty so they were emotionally distressed about there body image and experienced functional impairment. © 2017 The British Psychological Society.

United States Forest Disturbance Trends Observed Using Landsat Time Series

Science.gov (United States)

Masek, Jeffrey G.; Goward, Samuel N.; Kennedy, Robert E.; Cohen, Warren B.; Moisen, Gretchen G.; Schleeweis, Karen; Huang, Chengquan

2013-01-01

Disturbance events strongly affect the composition, structure, and function of forest ecosystems; however, existing U.S. land management inventories were not designed to monitor disturbance. To begin addressing this gap, the North American Forest Dynamics (NAFD) project has examined a geographic sample of 50 Landsat satellite image time series to assess trends in forest disturbance across the conterminous United States for 1985-2005. The geographic sample design used a probability-based scheme to encompass major forest types and maximize geographic dispersion. For each sample location disturbance was identified in the Landsat series using the Vegetation Change Tracker (VCT) algorithm. The NAFD analysis indicates that, on average, 2.77 Mha/yr of forests were disturbed annually, representing 1.09%/yr of US forestland. These satellite-based national disturbance rates estimates tend to be lower than those derived from land management inventories, reflecting both methodological and definitional differences. In particular the VCT approach used with a biennial time step has limited sensitivity to low-intensity disturbances. Unlike prior satellite studies, our biennial forest disturbance rates vary by nearly a factor of two between high and low years. High western US disturbance rates were associated with active fire years and insect activity, while variability in the east is more strongly related to harvest rates in managed forests. We note that generating a geographic sample based on representing forest type and variability may be problematic since the spatial pattern of disturbance does not necessarily correlate with forest type. We also find that the prevalence of diffuse, non-stand clearing disturbance in US forests makes the application of a biennial geographic sample problematic. Future satellite-based studies of disturbance at regional and national scales should focus on wall-to-wall analyses with annual time step for improved accuracy.

North American forest disturbance mapped from a decadal Landsat record

Science.gov (United States)

Jeffrey G. Masek; Chengquan Huang; Robert Wolfe; Warren Cohen; Forrest Hall; Jonathan Kutler; Peder. Nelson

2008-01-01

Forest disturbance and recovery are critical ecosystem processes, but the spatial pattern of disturbance has never been mapped across North America. The LEDAPS (Landsat Ecosystem Disturbance Adaptive Processing System) project has assembled a wall-to-wall record of stand-clearing disturbance (clearcut harvest, fire) for the United States and Canada for the period 1990-...

Scaling disturbance instead of richness to better understand anthropogenic impacts on biodiversity.

Directory of Open Access Journals (Sweden)

Stephen J Mayor

Full Text Available A primary impediment to understanding how species diversity and anthropogenic disturbance are related is that both diversity and disturbance can depend on the scales at which they are sampled. While the scale dependence of diversity estimation has received substantial attention, the scale dependence of disturbance estimation has been essentially overlooked. Here, we break from conventional examination of the diversity-disturbance relationship by holding the area over which species richness is estimated constant and instead manipulating the area over which human disturbance is measured. In the boreal forest ecoregion of Alberta, Canada, we test the dependence of species richness on disturbance scale, the scale-dependence of the intermediate disturbance hypothesis, and the consistency of these patterns in native versus exotic species and among human disturbance types. We related field observed species richness in 1 ha surveys of 372 boreal vascular plant communities to remotely sensed measures of human disturbance extent at two survey scales: local (1 ha and landscape (18 km2. Supporting the intermediate disturbance hypothesis, species richness-disturbance relationships were quadratic at both local and landscape scales of disturbance measurement. This suggests the shape of richness-disturbance relationships is independent of the scale at which disturbance is assessed, despite that local diversity is influenced by disturbance at different scales by different mechanisms, such as direct removal of individuals (local or indirect alteration of propagule supply (landscape. By contrast, predictions of species richness did depend on scale of disturbance measurement: with high local disturbance richness was double that under high landscape disturbance.

Suppressing non-periodically repeating disturbances in mechanical servo systems

NARCIS (Netherlands)

Tousain, R.L.; Boissy, J.C.; Norg, M.L.; Steinbuch, M.; Bosgra, O.H.

1998-01-01

Non-periodically repeating (NPR) disturbances are fixed-shape disturbances that occur randomly in time. We can provide a control system with the capability to suppress this type of disturbance by adding in parallel to the input of the nominal feedback controller a learning look-up-table based

A Full Disturbance Model for Reaction Wheels

NARCIS (Netherlands)

Le, M.P.; Ellenbroek, Marcellinus Hermannus Maria; Seiler, R; van Put, P.; Cottaar, E.J.E.

2014-01-01

Reaction wheels are rotating devices used for the attitude control of spacecraft. However, reaction wheels also generate undesired disturbances in the form of vibrations, which may have an adverse effect on the pointing accuracy and stability of spacecraft (optical) payloads. A disturbance model for

Human disturbances on coral reefs in Sri Lanka: A case study

Energy Technology Data Exchange (ETDEWEB)

Oehman, M C; Linden, O [Stockholm Univ. (Sweden). Dept. of Zoology; Rajasuriya, A [NARA, Crow Island, Colombo (Sri Lanka)

1993-01-01

The degradation of coral reefs in Sri Lanka has increased substantially over the last decades. Human activities causing this degradation include: mining for lime production, sewage discharges, discharges of oil and other pollutants in connection with shipping and port activities, destructive fishing practices, land and mangrove destruction, tourism and the collecting of fauna such as fish, shells and corals. In this study, three adjacent coral reefs; Bar Reef, Talawila Reef, and Kandakuliya Reef, which are widely scattered patch reefs off Kalpitiya Peninsula, northwestern Sri Lanka, were surveyed and compared in terms of their fish and coral diversity and abundance as well as human and natural disturbances. Information was gathered by snorkeling in visual overview surveys and by scuba diving in detailed transect surveys. When each reef was ranked according to the extent of live coral cover, and chaetodontid diversity, the results indicated that Bar Reef was in excellent condition, Talawila Reef was intermediate, and Kandakuliya Reef was in poor condition. The diversity of coral genera, the topographic relief and the proportion of coral rubble, did not follow the same pattern. The number of coral genera found was 49, while 283 fish species belonging to 51 families were recorded. Human disturbance factors on the reefs were found to be net fishing, boat anchoring and ornamental fish collection for the aquarium trade. Bottom.set nylon nets in particular were found to have a very destructive impact on the bottom fauna. 33 refs, 7 figs, 1 tab

Effects of climate change on ecological disturbances [Chapter 8

Science.gov (United States)

Danielle M. Malesky; Barbara J. Bentz; Gary R. Brown; Andrea R. Brunelle; John M. Buffington; Linda M. Chappell; R. Justin DeRose; John C. Guyon; Carl L. Jorgensen; Rachel A. Loehman; Laura L. Lowrey; Ann M. Lynch; Marek Matyjasik; Joel D. McMillin; Javier E. Mercado; Jesse L. Morris; Jose F. Negron; Wayne G. Padgett; Robert A. Progar; Carol B. Randall

2018-01-01

This chapter describes disturbance regimes in the Intermountain Adaptation Partnership (IAP) region, and potential shifts in these regimes as a consequence of observed and projected climate change. The term "disturbance regime" describes the general temporal and spatial characteristics of a disturbance agent (e.g., insects, disease, fire, weather, human...

Instrumentation for Power System Disturbance Monitoring, Data ...

African Journals Online (AJOL)

In this paper, the level of instrumentation for power system disturbance monitoring, data acquisition and control in Nigerian Electric Power System; National Electric Power Authority (NEPA) is presented. The need for accurate power system disturbance monitoring is highlighted. A feature of an adequate monitoring, data ...

Basic disturbances of information processing in psychosis prediction.

Science.gov (United States)

Bodatsch, Mitja; Klosterkötter, Joachim; Müller, Ralf; Ruhrmann, Stephan

2013-01-01

The basic symptoms (BS) approach provides a valid instrument in predicting psychosis onset and represents moreover a significant heuristic framework for research. The term "basic symptoms" denotes subtle changes of cognition and perception in the earliest and prodromal stages of psychosis development. BS are thought to correspond to disturbances of neural information processing. Following the heuristic implications of the BS approach, the present paper aims at exploring disturbances of information processing, revealed by functional magnetic resonance imaging (fMRI) and electro-encephalographic as characteristics of the at-risk state of psychosis. Furthermore, since high-risk studies employing ultra-high-risk criteria revealed non-conversion rates commonly exceeding 50%, thus warranting approaches that increase specificity, the potential contribution of neural information processing disturbances to psychosis prediction is reviewed. In summary, the at-risk state seems to be associated with information processing disturbances. Moreover, fMRI investigations suggested that disturbances of language processing domains might be a characteristic of the prodromal state. Neurophysiological studies revealed that disturbances of sensory processing may assist psychosis prediction in allowing for a quantification of risk in terms of magnitude and time. The latter finding represents a significant advancement since an estimation of the time to event has not yet been achieved by clinical approaches. Some evidence suggests a close relationship between self-experienced BS and neural information processing. With regard to future research, the relationship between neural information processing disturbances and different clinical risk concepts warrants further investigations. Thereby, a possible time sequence in the prodromal phase might be of particular interest.

Psychogenic nonepileptic seizures: a treatment review. What have we learned since the beginning of the millennium?

Directory of Open Access Journals (Sweden)

Baslet G

2012-12-01

Full Text Available Gaston BasletDepartment of Psychiatry, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USAAbstract: Psychogenic nonepileptic seizures (PNES can significantly affect an individual’s quality of life, the health care system, and even society. The first decade of the new millennium has seen renewed interest in this condition, but etiological understanding and evidence-based treatment availability remain limited. After the diagnosis of PNES is established, the first therapeutic step includes a presentation of the diagnosis that facilitates engagement in treatment. The purpose of this review is to present the current evidence of treatments for PNES published since the year 2000 and to discuss further needs for clinical treatment implementation and research. This article reviews clinical trials that have evaluated the efficacy of structured, standardized psychotherapeutic and psychopharmacological interventions. The primary outcome measure in clinical trials for PNES is event frequency, although it is questionable whether this is the most accurate indicator of functional recovery. Cognitive behavioral therapy has evidence of efficacy, including one pilot randomized, controlled trial where cognitive behavioral therapy was compared with standard medical care. The antidepressant sertraline did not show a significant difference in event frequency change when compared to placebo in a pilot randomized, double-blind, controlled trial, but it did show a significant pre- versus posttreatment decrease in the active arm. Other interventions that have shown efficacy in uncontrolled trials include augmented psychodynamic interpersonal psychotherapy, group psychodynamic psychotherapy, group psychoeducation, and the antidepressant venlafaxine. Larger clinical trials of these promising treatments are necessary, while other psychotherapeutic interventions such as hypnotherapy, mindfulness-based therapies, and eye movement desensitization and

A succession of theories: purging redundancy from disturbance theory.

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Pulsford, Stephanie A; Lindenmayer, David B; Driscoll, Don A

2016-02-01

The topics of succession and post-disturbance ecosystem recovery have a long and convoluted history. There is extensive redundancy within this body of theory, which has resulted in confusion, and the links among theories have not been adequately drawn. This review aims to distil the unique ideas from the array of theory related to ecosystem change in response to disturbance. This will help to reduce redundancy, and improve communication and understanding between researchers. We first outline the broad range of concepts that have developed over the past century to describe community change in response to disturbance. The body of work spans overlapping succession concepts presented by Clements in 1916, Egler in 1954, and Connell and Slatyer in 1977. Other theories describing community change include state and transition models, biological legacy theory, and the application of functional traits to predict responses to disturbance. Second, we identify areas of overlap of these theories, in addition to highlighting the conceptual and taxonomic limitations of each. In aligning each of these theories with one another, the limited scope and relative inflexibility of some theories becomes apparent, and redundancy becomes explicit. We identify a set of unique concepts to describe the range of mechanisms driving ecosystem responses to disturbance. We present a schematic model of our proposed synthesis which brings together the range of unique mechanisms that were identified in our review. The model describes five main mechanisms of transition away from a post-disturbance community: (i) pulse events with rapid state shifts; (ii) stochastic community drift; (iii) facilitation; (iv) competition; and (v) the influence of the initial composition of a post-disturbance community. In addition, stabilising processes such as biological legacies, inhibition or continuing disturbance may prevent a transition between community types. Integrating these six mechanisms with the functional

[Effect of trampling disturbance on soil infiltration of biological soil crusts].

Science.gov (United States)

Shi, Ya Fang; Zhao, Yun Ge; Li, Chen Hui; Wang, Shan Shan; Yang, Qiao Yun; Xie, Shen Qi

2017-10-01

The effect of trampling disturbance on soil infiltration of biological soil crusts was investigated by using simulated rainfall. The results showed that the trampling disturbance significantly increased soil surface roughness. The increasing extent depended on the disturbance intensity. Soil surface roughness values at 50% disturbance increased by 91% compared with the undisturbed treatment. The runoff was delayed by trampling disturbance. A linear increase in the time of runoff yield was observed along with the increasing disturbance intensity within 20%-50%. The time of runoff yield at 50% disturbance increased by 169.7% compared with the undisturbed treatment. Trampling disturbance increased soil infiltration and consequently decreased the runoff coefficient. The cumulative infiltration amount at 50% disturbance increased by 12.6% compared with the undisturbed treatment. Soil infiltration significant decreased when biocrusts were removed. The cumulative infiltration of the treatment of biocrusts removal decreased by 30.2% compared with the undisturbed treatment. Trampling disturbance did not significantly increase the soil loss when the distur bance intensity was lower than 50%, while the biocrusts removal resulted in 10 times higher in soil erosion modulus. The trampling disturbance of lower than 50% on biocrusts might improve soil infiltration and reduce the risk of runoff, thus might improve the soil moisture without obviously increa sing the soil loss.

Conservation of disturbance-dependent birds in eastern North America

Science.gov (United States)

William C. Hunter; David A. Buehler; Ronald A. Canterbury; John L. Confer; Paul B. Hamel

2001-01-01

Populations of most bird species associated with grassland, shrub-scrub habitats, and disturbed areas in forested habitats (hereafter all referred to as disturbance-dependent species) have declined steeply. However, a widespread perception exists that disturbance-dependent species are merely returning to population levels likely found by the first European explorers...

Visual binding abilities in the initial and advanced stages of schizophrenia

DEFF Research Database (Denmark)

Parnas, Josef; Vianin, P; Saebye, D

2001-01-01

OBJECTIVE: The study tests the hypothesis that intramodal visual binding is disturbed in schizophrenia and should be detectable in all illness stages as a stable trait marker. METHOD: Three groups of patients (rehospitalized chronic schizophrenic, first admitted schizophrenic and schizotypal...... to schizophrenic patients and to healthy subjects. Furthermore, chronic schizophrenia was associated with a poor performance on cortical tests of SWM, global local and on Raven. This association appears to be mediated by or linked to the chronicity of the illness. CONCLUSION: The study confirms a variety...... of neurocognitive deficits in schizophrenia which, however, in this sample seem to be linked to chronicity of illness. However, certain aspects of visual processing concerned with Gestalt extraction deserve attention as potential vulnerability- or prodrome- indicators. The initial hypothesis of the study...

Postoperative changes in visual evoked potentials and cognitive function tests following sevoflurane anaesthesia.

LENUS (Irish Health Repository)

Iohom, G

2012-02-03

We tested the hypothesis that minor disturbance of the visual pathway persists following general anaesthesia even when clinical discharge criteria are met. To test this, we measured visual evoked potentials (VEPs) in 13 ASA I or II patients who did not receive any pre-anaesthetic medication and underwent sevoflurane anaesthesia. VEPs were recorded on four occasions, before anaesthesia and at 30, 60, and 90 min after emergence from anaesthesia. Patients completed visual analogue scales (VAS) for sedation and anxiety, a Trieger Dot Test (TDT) and a Digit Symbol Substitution Test (DSST) immediately before each VEP recording. These results were compared using Student\\'s t-test. P<0.05 was considered significant. VEP latency was prolonged (P<0.001) and amplitude diminished (P<0.05) at 30, 60, and 90 min after emergence from anaesthesia, when VAS scores for sedation and anxiety, TDT, and DSST had returned to pre-anaesthetic levels.

Harmonic disturbance location by applying Bayesian inference

NARCIS (Netherlands)

Ye, G.; Xiang, Y.; Cuk, V.; Cobben, J.F.G.

2016-01-01

Harmonic pollution is one of the most important power quality issues in electric power systems. Correct location of the main harmonic disturbance source is a key step to solve the problem. This paper presents a method to detect the location of harmonic disturbance source in low voltage network

Speech and Language Disturbances in Neurology Practice

Directory of Open Access Journals (Sweden)

Oğuz Tanrıdağ

2009-12-01

Full Text Available Despite the well-known facts discerned from interesting cases of speech and language disturbances over thousands of years, the scientific background and the limitless discussions for nearly 150 years, this field has been considered one of the least important subjects in neurological sciences. In this review, we first analyze the possible causes for this “stepchild” attitude towards this subject and we then summarize the practical aspects concerning speech and language disturbances. Our underlying expectation with this review is to explain the facts concerning those disturbances that might offer us opportunities to better understand the nervous system and the affected patients

Automated recognition system for power quality disturbances

Science.gov (United States)

Abdelgalil, Tarek

The application of deregulation policies in electric power systems has resulted in the necessity to quantify the quality of electric power. This fact highlights the need for a new monitoring strategy which is capable of tracking, detecting, classifying power quality disturbances, and then identifying the source of the disturbance. The objective of this work is to design an efficient and reliable power quality monitoring strategy that uses the advances in signal processing and pattern recognition to overcome the deficiencies that exist in power quality monitoring devices. The purposed monitoring strategy has two stages. The first stage is to detect, track, and classify any power quality violation by the use of on-line measurements. In the second stage, the source of the classified power quality disturbance must be identified. In the first stage, an adaptive linear combiner is used to detect power quality disturbances. Then, the Teager Energy Operator and Hilbert Transform are utilized for power quality event tracking. After the Fourier, Wavelet, and Walsh Transforms are employed for the feature extraction, two approaches are then exploited to classify the different power quality disturbances. The first approach depends on comparing the disturbance to be classified with a stored set of signatures for different power quality disturbances. The comparison is developed by using Hidden Markov Models and Dynamic Time Warping. The second approach depends on employing an inductive inference to generate the classification rules directly from the data. In the second stage of the new monitoring strategy, only the problem of identifying the location of the switched capacitor which initiates the transients is investigated. The Total Least Square-Estimation of Signal Parameters via Rotational Invariance Technique is adopted to estimate the amplitudes and frequencies of the various modes contained in the voltage signal measured at the facility entrance. After extracting the

Do Magnetic Resonance Imaging Characteristics of Full-Thickness Rotator Cuff Tears Correlate With Sleep Disturbance?

Science.gov (United States)

Reyes, Bryan A; Hull, Brandon R; Kurth, Alexander B; Kukowski, Nathan R; Mulligan, Edward P; Khazzam, Michael S

2017-11-01

Many patients with rotator cuff tears suffer from nocturnal shoulder pain, resulting in sleep disturbance. To determine whether rotator cuff tear size correlated with sleep disturbance in patients with full-thickness rotator cuff tears. Cross-sectional study; Level of evidence, 3. Patients with a diagnosis of unilateral full-thickness rotator cuff tears (diagnosed via magnetic resonance imaging [MRI]) completed the Pittsburgh Sleep Quality Index (PSQI), a visual analog scale (VAS) quantifying their shoulder pain, and the American Shoulder and Elbow Surgeons (ASES) questionnaire. Shoulder MRI scans were analyzed for anterior-posterior tear size (mm), tendon retraction (mm), Goutallier grade (0-4), number of tendons involved (1-4), muscle atrophy (none, mild, moderate, or severe), and humeral head rise (present or absent). Bivariate correlations were calculated between the MRI characteristics and baseline survey results. A total of 209 patients with unilateral full-thickness rotator cuff tears were included in this study: 112 (54%) female and 97 (46%) male (mean age, 64.1 years). On average, shoulder pain had been present for 24 months. The mean PSQI score was 9.8, and the mean VAS score was 5.0. No significant correlations were found between any of the rotator cuff tear characteristics and sleep quality. Only tendon retraction had a significant correlation with pain. Although rotator cuff tears are frequently associated with nocturnal pain and sleep disruption, this study demonstrated that morphological characteristics of full-thickness rotator cuff tears, such as size and tendon retraction, do not correlate with sleep disturbance and have little to no correlation with pain levels.

Thermoluminescent Signals Caused by Disturbing Effects

International Nuclear Information System (INIS)

German, U.; Weinstein, M.; Ben-Shachar, B.

1999-01-01

One of the major sources of uncertainty in the measurement of low radiation doses by means of thermoluminescence dosemeters is the presence of disturbing thermoluminescence signals, especially luminescence caused by visible light, and by materials attached to the heated areas. Glow curves of thermoluminescence dosemeters contain useful information that can improve the accuracy and the reliability of the thermoluminescent measurements. The influence of the various disturbing effects can be recognised in the shape of the glow curves and can sometimes be separated from the exposure. Some examples are presented of signals arising from the two disturbing effects mentioned above, the signal contributed by Teflon used in the TLD-100 cards of Bicron/Harshaw and some abnormal glow curves due to dirt attached to the cards. Subtraction of the contributions due to these effects is suggested to obtain the net exposure signal. (author)

Work Time Control and Sleep Disturbances

DEFF Research Database (Denmark)

Salo, Paula; Ala-Mursula, Leena; Rod, Naja Hulvej

2014-01-01

OBJECTIVES: Employee control over work times has been associated with favorable psychosocial and health-related outcomes, but the evidence regarding sleep quality remains inconclusive. We examined cross-sectional and prospective associations between work time control and sleep disturbances...... in a large working population, taking into account total hours worked. METHODS: The data were from a full-panel longitudinal cohort study of Finnish public sector employees who responded to questions on work time control and sleep disturbances in years 2000-2001, 2004-2005, 2008-2009, and 2012. The analysis....... RESULTS: Consistently in both cross-sectional and longitudinal models, less control over work time was associated with greater sleep disturbances in the total population and among those working normal 40-hour weeks. Among participants working more than 40 hours a week, work time that was both very high...

Interocular differences in visual quality due to ocular aberrations and scattering in a patient with post-traumatic anisocoria: A case report

Directory of Open Access Journals (Sweden)

Andrés Gené-Sampedro

2012-04-01

Full Text Available A 41-year-old patient with visual disturbances after an ocular trauma in right eye three years before was carefully analyzed and discussed. No corneal or intraocular sequelae were present. Only a significant anisocoria could be observed. Right eye (RE achieved a best spectacle-corrected visual acuity (BSCVA of 0.05 LogMAR with a refraction of +0.50 sphere and −1.25 cylinder. Left eye (LE achieved a BSCVA of 0.0 LogMAR with a refraction of +0.75 sphere and −1.00 cylinder. In photopic conditions pupil diameter was 4.96 mm for RE and 3.02 mm for LE whereas in scotopic conditions, these values were 7.45 mm and 6.71 mm, respectively. More significant levels of higher-order corneal and ocular aberrations were found in RE for the same pupil size. In addition, the scattering index (OSI was 3.8 in RE and 1.0 in LE (4-mm pupil. In conclusion, anisocoria can lead to relevant visual disturbances if significant interocular differences in ocular aberrations and scattering are present.

Language disturbance and functioning in first episode psychosis.

Science.gov (United States)

Roche, Eric; Segurado, Ricardo; Renwick, Laoise; McClenaghan, Aisling; Sexton, Sarah; Frawley, Timothy; Chan, Carol K; Bonar, Maurice; Clarke, Mary

2016-01-30

Language disturbance has a central role in the presentation of psychotic disorders however its relationship with functioning requires further clarification, particularly in first episode psychosis (FEP). Both language disturbance and functioning can be evaluated with clinician-rated and performance-based measures. We aimed to investigate the concurrent association between clinician-rated and performance-based measures of language disturbance and functioning in FEP. We assessed 108 individuals presenting to an Early Intervention in Psychosis Service in Ireland. Formal thought disorder (FTD) dimensions and bizarre idiosyncratic thinking (BIT) were rated with structured assessment tools. Functioning was evaluated with a performance-based instrument, a clinician-rated measure and indicators of real-world functioning. The disorganisation dimension of FTD was significantly associated with clinician-rated measures of occupational and social functioning (Beta=-0.19, P<0.05 and Beta=-0.31, P<0.01, respectively). BIT was significantly associated with the performance-based measure of functioning (Beta=-0.22, P<0.05). Language disturbance was of less value in predicting real-world measures of functioning. Clinician-rated and performance-based assessments of language disturbance are complementary and each has differential associations with functioning. Communication disorders should be considered as a potential target for intervention in FEP, although further evaluation of the longitudinal relationship between language disturbance and functioning should be undertaken. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Driver Distraction Using Visual-Based Sensors and Algorithms.

Science.gov (United States)

Fernández, Alberto; Usamentiaga, Rubén; Carús, Juan Luis; Casado, Rubén

2016-10-28

Driver distraction, defined as the diversion of attention away from activities critical for safe driving toward a competing activity, is increasingly recognized as a significant source of injuries and fatalities on the roadway. Additionally, the trend towards increasing the use of in-vehicle information systems is critical because they induce visual, biomechanical and cognitive distraction and may affect driving performance in qualitatively different ways. Non-intrusive methods are strongly preferred for monitoring distraction, and vision-based systems have appeared to be attractive for both drivers and researchers. Biomechanical, visual and cognitive distractions are the most commonly detected types in video-based algorithms. Many distraction detection systems only use a single visual cue and therefore, they may be easily disturbed when occlusion or illumination changes appear. Moreover, the combination of these visual cues is a key and challenging aspect in the development of robust distraction detection systems. These visual cues can be extracted mainly by using face monitoring systems but they should be completed with more visual cues (e.g., hands or body information) or even, distraction detection from specific actions (e.g., phone usage). Additionally, these algorithms should be included in an embedded device or system inside a car. This is not a trivial task and several requirements must be taken into account: reliability, real-time performance, low cost, small size, low power consumption, flexibility and short time-to-market. The key points for the development and implementation of sensors to carry out the detection of distraction will also be reviewed. This paper shows a review of the role of computer vision technology applied to the development of monitoring systems to detect distraction. Some key points considered as both future work and challenges ahead yet to be solved will also be addressed.

Driver Distraction Using Visual-Based Sensors and Algorithms

Directory of Open Access Journals (Sweden)

Alberto Fernández

2016-10-01

Full Text Available Driver distraction, defined as the diversion of attention away from activities critical for safe driving toward a competing activity, is increasingly recognized as a significant source of injuries and fatalities on the roadway. Additionally, the trend towards increasing the use of in-vehicle information systems is critical because they induce visual, biomechanical and cognitive distraction and may affect driving performance in qualitatively different ways. Non-intrusive methods are strongly preferred for monitoring distraction, and vision-based systems have appeared to be attractive for both drivers and researchers. Biomechanical, visual and cognitive distractions are the most commonly detected types in video-based algorithms. Many distraction detection systems only use a single visual cue and therefore, they may be easily disturbed when occlusion or illumination changes appear. Moreover, the combination of these visual cues is a key and challenging aspect in the development of robust distraction detection systems. These visual cues can be extracted mainly by using face monitoring systems but they should be completed with more visual cues (e.g., hands or body information or even, distraction detection from specific actions (e.g., phone usage. Additionally, these algorithms should be included in an embedded device or system inside a car. This is not a trivial task and several requirements must be taken into account: reliability, real-time performance, low cost, small size, low power consumption, flexibility and short time-to-market. The key points for the development and implementation of sensors to carry out the detection of distraction will also be reviewed. This paper shows a review of the role of computer vision technology applied to the development of monitoring systems to detect distraction. Some key points considered as both future work and challenges ahead yet to be solved will also be addressed.

Sleep Disturbances in Patients with Rheumatoid Arthritis | Abbasi ...

African Journals Online (AJOL)

Sleep Disturbances in Patients with Rheumatoid Arthritis. ... that insomnia, pain and disease intensity were the most important factors that ... that sleep disturbances are frequent in patients with RA and may contribute to disease severity.

Distributed Coordination of Fractional Dynamical Systems with Exogenous Disturbances

Directory of Open Access Journals (Sweden)

Hongyong Yang

2014-01-01

Full Text Available Distributed coordination of fractional multiagent systems with external disturbances is studied. The state observer of fractional dynamical system is presented, and an adaptive pinning controller is designed for a little part of agents in multiagent systems without disturbances. This adaptive pinning controller with the state observer can ensure multiple agents' states reaching an expected reference tracking. Based on disturbance observers, the controllers are composited with the pinning controller and the state observer. By applying the stability theory of fractional order dynamical systems, the distributed coordination of fractional multiagent systems with external disturbances can be reached asymptotically.

Metoprolol-induced visual hallucinations: a case series

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Goldner Jonathan A

2012-02-01

Full Text Available Abstract Introduction Metoprolol is a widely used beta-adrenergic blocker that is commonly prescribed for a variety of cardiovascular syndromes and conditions. While central nervous system adverse effects have been well-described with most beta-blockers (especially lipophilic agents such as propranolol, visual hallucinations have been only rarely described with metoprolol. Case presentations Case 1 was an 84-year-old Caucasian woman with a history of hypertension and osteoarthritis, who suffered from visual hallucinations which she described as people in her bedroom at night. They would be standing in front of the bed or sitting on chairs watching her when she slept. Numerous medications were stopped before her physician realized the metoprolol was the causative agent. The hallucinations resolved only after discontinuation of this medication. Case 2 was a 62-year-old Caucasian man with an inferior wall myocardial infarction complicated by cardiac arrest, who was successfully resuscitated and discharged from the hospital on metoprolol. About 18 months after discharge, he related to his physician that he had been seeing dead people at night. He related his belief that since he 'had died and was brought back to life', he was now seeing people from the after-life. Upon discontinuation of the metoprolol the visual disturbances resolved within several days. Case 3 was a 68 year-old Caucasian woman with a history of severe hypertension and depression, who reported visual hallucinations at night for years while taking metoprolol. These included awakening during the night with people in her bedroom and seeing objects in her room turn into animals. After a new physician switched her from metoprolol to atenolol, the visual hallucinations ceased within four days. Conclusion We suspect that metoprolol-induced visual hallucinations may be under-recognized and under-reported. Patients may frequently fail to acknowledge this adverse effect believing that they

Effects of climate change on ecological disturbance in the northern Rockies

Science.gov (United States)

Loehman, Rachel A.; Bentz, Barbara J.; DeNitto, Gregg A.; Keane, Robert E.; Manning, Mary E.; Duncan, Jacob P.; Egan, Joel M.; Jackson, Marcus B.; Kegley, Sandra; Lockman, I. Blakey; Pearson, Dean E.; Powell, James A.; Shelly, Steve; Steed, Brytten E.; Zambino, Paul J.; Halofsky, Jessica E.; Peterson, David L.

2018-01-01

Disturbances alter ecosystem, community, or population structure and change elements of the biological and/or physical environment. Climate changes can alter the timing, magnitude, frequency, and duration of disturbance events, as well as the interactions of disturbances on a landscape, and climate change may already be affecting disturbance events and regimes. Interactions among disturbance regimes, such as the cooccurrence in space and time of bark beetle outbreaks and wildfires, can result in highly visible, rapidly occurring, and persistent changes in landscape composition and structure. Understanding how altered disturbance patterns and multiple disturbance interactions might result in novel and emergent landscape behaviors is critical for addressing climate change impacts and for designing land management strategies that are appropriate for future climates This chapter describes the ecology of important disturbance regimes in the Northern Rockies region, and potential shifts in these regimes as a consequence of observed and projected climate change. We summarize five disturbance types present in the Northern Rockies that are sensitive to a changing climate--wildfires, bark beetles, white pine blister rust (Cronartium ribicola), other forest diseases, and nonnative plant invasions—and provide information that can help managers anticipate how, when, where, and why climate changes may alter the characteristics of disturbance regimes.

Response of a Hypersonic Boundary Layer to Freestream Pulse Acoustic Disturbance

Directory of Open Access Journals (Sweden)

Zhenqing Wang

2014-01-01

Full Text Available The response of hypersonic boundary layer over a blunt wedge to freestream pulse acoustic disturbance was investigated. The stability characteristics of boundary layer for freestream pulse wave and continuous wave were analyzed comparatively. Results show that freestream pulse disturbance changes the thermal conductivity characteristics of boundary layer. For pulse wave, the number of main disturbance clusters decreases and the frequency band narrows along streamwise. There are competition and disturbance energy transfer among different modes in boundary layer. The dominant mode of boundary layer has an inhibitory action on other modes. Under continuous wave, the disturbance modes are mainly distributed near fundamental and harmonic frequencies, while under pulse wave, the disturbance modes are widely distributed in different modes. For both pulse and continuous waves, most of disturbance modes slide into a lower-growth or decay state in downstream, which is tending towards stability. The amplitude of disturbance modes in boundary layer under continuous wave is considerably larger than pulse wave. The growth rate for the former is also considerably larger than the later the disturbance modes with higher growth are mainly distributed near fundamental and harmonic frequencies for the former, while the disturbance modes are widely distributed in different frequencies for the latter.

Response of a hypersonic boundary layer to freestream pulse acoustic disturbance.

Science.gov (United States)

Wang, Zhenqing; Tang, Xiaojun; Lv, Hongqing

2014-01-01

The response of hypersonic boundary layer over a blunt wedge to freestream pulse acoustic disturbance was investigated. The stability characteristics of boundary layer for freestream pulse wave and continuous wave were analyzed comparatively. Results show that freestream pulse disturbance changes the thermal conductivity characteristics of boundary layer. For pulse wave, the number of main disturbance clusters decreases and the frequency band narrows along streamwise. There are competition and disturbance energy transfer among different modes in boundary layer. The dominant mode of boundary layer has an inhibitory action on other modes. Under continuous wave, the disturbance modes are mainly distributed near fundamental and harmonic frequencies, while under pulse wave, the disturbance modes are widely distributed in different modes. For both pulse and continuous waves, most of disturbance modes slide into a lower-growth or decay state in downstream, which is tending towards stability. The amplitude of disturbance modes in boundary layer under continuous wave is considerably larger than pulse wave. The growth rate for the former is also considerably larger than the later the disturbance modes with higher growth are mainly distributed near fundamental and harmonic frequencies for the former, while the disturbance modes are widely distributed in different frequencies for the latter.

Model reduction of nonlinear systems subject to input disturbances

KAUST Repository

Ndoye, Ibrahima

2017-07-10

The method of convex optimization is used as a tool for model reduction of a class of nonlinear systems in the presence of disturbances. It is shown that under some conditions the nonlinear disturbed system can be approximated by a reduced order nonlinear system with similar disturbance-output properties to the original plant. The proposed model reduction strategy preserves the nonlinearity and the input disturbance nature of the model. It guarantees a sufficiently small error between the outputs of the original and the reduced-order systems, and also maintains the properties of input-to-state stability. The matrices of the reduced order system are given in terms of a set of linear matrix inequalities (LMIs). The paper concludes with a demonstration of the proposed approach on model reduction of a nonlinear electronic circuit with additive disturbances.

Cholinergic modulation of visual and attentional brain responses in Alzheimer's disease and in health

OpenAIRE

Bentley, P.; Driver, J.; Dolan, R.J.

2007-01-01

Visuo-attentional deficits occur early in Alzheimer's disease (AD) and are considered more responsive to pro-cholinergic therapy than characteristic memory disturbances. We hypothesised that neural responses in AD during visual attentional processing would be impaired relative to controls, yet partially susceptible to improvement with cholinesterase inhibition. We studied 16 mild AD patients and 17 age-matched healthy controls, using fMRI-scanning to enable within-subject placebo-controlled c...

Homicides of law enforcement officers responding to domestic disturbance calls.

Science.gov (United States)

Kercher, Cassandra; Swedler, David I; Pollack, Keshia M; Webster, Daniel W

2013-10-01

To describe the law enforcement officer (LEO), encounter, perpetrator and victim characteristics of domestic disturbance-related LEO homicides in the USA from 1996 to 2010. Narrative text analysis was conducted on the Federal Bureau of Investigation's annual report 'Law Enforcement Officers Killed and Assaulted'. Potential cases were confirmed if the narrative included the term 'domestic disturbance' or a domestic disturbance situation was described. 116 LEOs were killed while responding to domestic disturbance calls. Ninety-five per cent of these homicides were committed with a firearm. Sixty-seven per cent of LEOs were wearing body armour when killed; however, 52% received the fatal wound to the head/neck. Sixty-one per cent of suspects had a criminal history mentioned within the narratives and perpetrators of intimate partner violence (IPV) were more likely to be killed by LEOs than suspects involved in other forms of domestic violence. Victims of the domestic disturbance were killed in 21% of the IPV-related LEO homicide cases as opposed to only 5% of other domestic disturbance calls. A firearm was the most common weapon used in the murder of a domestic disturbance victim (86%). This study describes domestic disturbance-related LEO homicides. Future research in this area should further examine the dangers unique to domestic disturbance calls. A longitudinal analysis could provide greater understanding of the injury and mortality risks faced by LEOs, in order to inform homicide prevention among law enforcement.

Quantifying human disturbance in watersheds: Variable selection and performance of a GIS-based disturbance index for predicting the biological condition of perennial streams

Science.gov (United States)

Falcone, James A.; Carlisle, Daren M.; Weber, Lisa C.

2010-01-01

Characterizing the relative severity of human disturbance in watersheds is often part of stream assessments and is frequently done with the aid of Geographic Information System (GIS)-derived data. However, the choice of variables and how they are used to quantify disturbance are often subjective. In this study, we developed a number of disturbance indices by testing sets of variables, scoring methods, and weightings of 33 potential disturbance factors derived from readily available GIS data. The indices were calibrated using 770 watersheds located in the western United States for which the severity of disturbance had previously been classified from detailed local data by the United States Environmental Protection Agency (USEPA) Environmental Monitoring and Assessment Program (EMAP). The indices were calibrated by determining which variable or variable combinations and aggregation method best differentiated between least- and most-disturbed sites. Indices composed of several variables performed better than any individual variable, and best results came from a threshold method of scoring using six uncorrelated variables: housing unit density, road density, pesticide application, dam storage, land cover along a mainstem buffer, and distance to nearest canal/pipeline. The final index was validated with 192 withheld watersheds and correctly classified about two-thirds (68%) of least- and most-disturbed sites. These results provide information about the potential for using a disturbance index as a screening tool for a priori ranking of watersheds at a regional/national scale, and which landscape variables and methods of combination may be most helpful in doing so.

The prevalence of visual symptoms in poppers users: a global survey.

Science.gov (United States)

Davies, Andrew J; Borschmann, Rohan; Kelly, Simon P; Ramsey, John; Ferris, Jason; Winstock, Adam R

2017-01-01

The use of 'poppers' (volatile alkyl nitrites) has been associated with the development of visual symptoms secondary to the development of maculopathy. There are currently no data regarding the prevalence of this condition among poppers users. The aim of this study was to quantify the presence of visual symptoms among poppers users from a global cohort. The Global Drug Survey (GDS) conducts annual anonymous online surveys of drug and alcohol use. Within the 2012 GDS, questions were inserted regarding the presence of visual symptoms in poppers users. The GDS received a total of 21 575 valid responses, with a total of 17 479 from the UK, Australia, USA and Eurozone. Within these areas, 5152 (29.5%) had used poppers within their lifetime and 1322 (7.6%) within the previous year. Of the 'last year' users, when asked the question: 'Do you think poppers use has affected your eyesight?', 29 (2.2%) people responded 'yes', 130 (10.0%) responded 'maybe' and 1146 (87.8%) responded 'no (17 people did not answer). Both multiple choice and free-text responses regarding the nature of visual symptoms correlated with the central visual disturbance that would be expected from maculopathy. There was significant increased symptom prevalence with age (likelihood ratio (χ 2 )=19.0; ppoppers users have visual symptoms. Clinical correlation is required to determine whether these reported symptoms are due to poppers associated maculopathy, or an alternative cause.

Sudden Ionospheric Disturbances (SID)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Sudden ionospheric disturbances (SID) are caused by solar flare enhanced X-rays in the 1 to 10 angstrom range. Solar flares can produce large increases of ionization...

Persistent visual impairment in multiple sclerosis: prevalence, mechanisms and resulting disability.

Science.gov (United States)

Jasse, Laurence; Vukusic, Sandra; Durand-Dubief, Françoise; Vartin, Cristina; Piras, Carolina; Bernard, Martine; Pélisson, Denis; Confavreux, Christian; Vighetto, Alain; Tilikete, Caroline

2013-10-01

The objective of this article is to evaluate in multiple sclerosis (MS) patients the prevalence of persistent complaints of visual disturbances and the mechanisms and resulting functional disability of persistent visual complaints (PVCs). Firstly, the prevalence of PVCs was calculated in 303 MS patients. MS-related data of patients with or without PVCs were compared. Secondly, 70 patients with PVCs performed an extensive neuro-ophthalmologic assessment and a vision-related quality of life questionnaire, the National Eye Institute Visual Functionary Questionnaire (NEI-VFQ-25). PVCs were reported in 105 MS patients (34.6%). Patients with PVCs had more frequently primary progressive MS (30.5% vs 13.6%) and more neuro-ophthalmologic relapses (1.97 vs 1.36) than patients without PVCs. In the mechanisms/disability study, an afferent visual and an ocular-motor pathways dysfunction were respectively diagnosed in 41 and 59 patients, mostly related to bilateral optic neuropathy and bilateral internuclear ophthalmoplegia. The NEI-VFQ 25 score was poor and significantly correlated with the number of impaired neuro-ophthalmologic tests. Our study emphasizes the high prevalence of PVC in MS patients. Regarding the nature of neuro-ophthalmologic deficit, our results suggest that persistent optic neuropathy, as part of the progressive evolution of the disease, is not rare. We also demonstrate that isolated ocular motor dysfunctions induce visual disability in daily life.

Mechanical disturbances in superconducting magnets

International Nuclear Information System (INIS)

Sugimoto, Makoto

1990-03-01

The stress distribution in a small epoxy-impregnated Nb 3 Sn coil was calculated by the finite element method. Mechanical disturbances due to the electromagnetic force in the magnet are discussed. The coil stability in relation with the stress distribution is also discussed by using the experimental results. To evaluate such stresses, a calculation model was investigated. It was found that the model, which removed the internal bore element in the model magnet, gave a reasonable condition to estimate to stress. A quench mechanism due to mechanical disturbances in superconducting magnets is discussed. According to this mechanism, an internal slit was assumed as the reason for the mechanical disturbance. The internal slit is generated at the boundary between the superconductor and the bore element by the thermally induced stress. When charging a magnet, the induced electromagnetic force results in a stress concentration at the slit, and hence to an enlargement of it. During the enlargement of the internal slit, heat is generated at the top of it. Such heat generation from a mechanical disturbance can induce a quench. Through these investigations, the following coil manufacturing method can be proposed to reduce such stresses: the magnet should be manufactured to separate the bore element from the superconductor and this separation technique can reduce the boundary stress during cool-down. Actually, a thin teflon film at the boundary between the superconductor and the bore element can be used as a separator. Another separation technique is a teflon coating on the internal bore element. The separation technique should result in a stable epoxy-impregnated superconducting magnet. (J.P.N.)

Visual acuity and quality of life in dry eye disease: Proceedings of the OCEAN group meeting.

Science.gov (United States)

Benítez-Del-Castillo, José; Labetoulle, Marc; Baudouin, Christophe; Rolando, Maurizio; Akova, Yonca A; Aragona, Pasquale; Geerling, Gerd; Merayo-Lloves, Jesús; Messmer, Elisabeth M; Boboridis, Kostas

2017-04-01

Dry eye disease (DED) results in tear film instability and hyperosmolarity, inflammation of the ocular surface and, ultimately, visual disturbance that can significantly impact a patient's quality of life. The effects on visual acuity result in difficulties with driving, reading and computer use and negatively impact psychological health. These effects also extend to the workplace, with a loss of productivity and quality of work causing substantial economic losses. The effects of DED and the impact on vision experienced by patients may not be given sufficient importance by ophthalmologists. Functional visual acuity (FVA) is a measure of visual acuity after sustained eye opening without blinking for at least 10 s and mimics the sustained visual acuity of daily life. Measuring dynamic FVA allows the detection of impaired visual function in patients with DED who may display normal conventional visual acuity. There are currently several tests and methods that can be used to measure dynamic visual function: the SSC-350 FVA measurement system, assessment of best-corrected visual acuity decay using the interblink visual acuity decay test, serial measurements of ocular and corneal higher order aberrations, and measurement of dynamic vision quality using the Optical Quality Analysis System. Although the equipment for these methods may be too large or unaffordable for use in clinical practice, FVA testing is an important assessment for DED. Copyright © 2016 Elsevier Inc. All rights reserved.

Excavation/Fill/Soil Disturbance, Self-Study #31419

Energy Technology Data Exchange (ETDEWEB)

Grogin, Phillip W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2018-02-06

This course, Excavation/Fill/Soil Disturbance Self-Study (#31419), presents an overview of the hazards, controls, and requirements that affect safe excavations at Los Alamos National Laboratory (LANL). An overview of the LANL excavation/fill/soil disturbance permit (EXID permit) approval process is also presented, along with potholing requirements for planning and performing excavations at LANL.

Modeling aircraft noise induced sleep disturbance

Science.gov (United States)

McGuire, Sarah M.

One of the primary impacts of aircraft noise on a community is its disruption of sleep. Aircraft noise increases the time to fall asleep, the number of awakenings, and decreases the amount of rapid eye movement and slow wave sleep. Understanding these changes in sleep may be important as they could increase the risk for developing next-day effects such as sleepiness and reduced performance and long-term health effects such as cardiovascular disease. There are models that have been developed to predict the effect of aircraft noise on sleep. However, most of these models only predict the percentage of the population that is awakened. Markov and nonlinear dynamic models have been developed to predict an individual's sleep structure during the night. However, both of these models have limitations. The Markov model only accounts for whether an aircraft event occurred not the noise level or other sound characteristics of the event that may affect the degree of disturbance. The nonlinear dynamic models were developed to describe normal sleep regulation and do not have a noise effects component. In addition, the nonlinear dynamic models have slow dynamics which make it difficult to predict short duration awakenings which occur both spontaneously and as a result of nighttime noise exposure. The purpose of this research was to examine these sleep structure models to determine how they could be altered to predict the effect of aircraft noise on sleep. Different approaches for adding a noise level dependence to the Markov Model was explored and the modified model was validated by comparing predictions to behavioral awakening data. In order to determine how to add faster dynamics to the nonlinear dynamic sleep models it was necessary to have a more detailed sleep stage classification than was available from visual scoring of sleep data. An automatic sleep stage classification algorithm was developed which extracts different features of polysomnography data including the

Post-disturbance sediment recovery: Implications for watershed resilience

Science.gov (United States)

Rathburn, Sara L.; Shahverdian, Scott M.; Ryan, Sandra E.

2018-03-01

Sediment recovery following disturbances is a measure of the time required to attain pre-disturbance sediment fluxes. Insight into the controls on recovery processes and pathways builds understanding of geomorphic resilience. We assess post-disturbance sediment recovery in three small (1.5-100 km2), largely unaltered watersheds within the northern Colorado Rocky Mountains affected by wildfires, floods, and debris flows. Disturbance regimes span 102 (floods, debris flows) to 103 years (wildfires). For all case studies, event sediment recovery followed a nonlinear pattern: initial high sediment flux during single precipitation events or high annual snowmelt runoff followed by decreasing sediment fluxes over time. Disturbance interactions were evaluated after a high-severity fire within the South Fork Cache la Poudre basin was followed by an extreme flood one year post-fire. This compound disturbance hastened suspended sediment recovery to pre-fire concentrations 3 years after the fire. Wildfires over the last 1900 YBP in the South Fork basin indicate fire recurrence intervals of 600 years. Debris flows within the upper Colorado River basin over the last two centuries have shifted the baseline of sediment recovery caused by anthropogenic activities that increased debris flow frequency. An extreme flood on North St. Vrain Creek with an impounding reservoir resulted in extreme sedimentation that led to a physical state change. We introduce an index of resilience as sediment recovery/disturbance recurrence interval, providing a relative comparison between sites. Sediment recovery and channel form resilience may be inversely related because of high or low physical complexity in streams. We propose management guidelines to enhance geomorphic resilience by promoting natural processes that maintain physical complexity. Finally, sediment connectivity within watersheds is an additional factor to consider when establishing restoration treatment priorities.

Recurrent rhabdomyolysis in a teenager with psychosis-intermittent hyponatremia-polydipsia syndrome.

Science.gov (United States)

Shenoi, Asha N; Stockwell, Jana

2015-04-01

To report a case of recurrent hyponatremia and rhabdomyolysis in a teenager with psychogenic polydipsia. A 16-year-old boy was admitted with recurrent episodes of hyponatremia and rhabdomyolysis secondary to psychogenic polydipsia. He was treated with hypertonic saline, intravenous fluids, and supportive care. Psychogenic polydipsia is a condition characterized by compulsive drinking. Severe hyponatremia is a rare, but serious complication in patients with psychogenic polydipsia. Failure in cell volume regulatory mechanisms, defective osmoregulation, defective urinary dilution, and enhanced secretion of vasopressin are believed to play a role in the development of hyponatremia. Rhabdomyolysis can complicate severe hyponatremia, although the exact mechanism is not known. Antipsychotic drugs are also implicated in rhabdomyolysis. Severe hyponatremia and rhabdomyolysis can complicate psychogenic polydipsia. Patients receiving antipsychotic drugs with concomitant severe hyponatremia need to be monitored for rhabdomyolysis.

Disturbance regimes and the historical range and variation in terrestrial ecosystems

Science.gov (United States)

Robert Keane

2017-01-01

Disturbances are major drivers of ecological dynamics and it is the cumulative effects of disturbances across space and time that define a disturbance regime and dictate biodiversity by influencing the ranges of vegetation structures, compositions, and processes on landscapes. This range and variation of landscape characteristics under historical disturbance regimes...

Disturbance-mediated competition between perennial plants along a resource supply gradient

Science.gov (United States)

J. Stephen. Brewer

2011-01-01

Traditional views of ecological disturbance emphasize the role that physical disturbances play in reducing competition between populations and maintaining species coexistence. I present an alternative view that employs a simple Lotka–Volterra model to demonstrate how disturbance resistance, disturbance resilience and resource storage can increase competition between...

Sleep Disturbance During Smoking Cessation: Withdrawal or Side Effect of Treatment?

Science.gov (United States)

Ashare, Rebecca L; Lerman, Caryn; Tyndale, Rachel F; Hawk, Larry W; George, Tony P; Cinciripini, Paul; Schnoll, Robert A

2017-06-01

The nicotine-metabolite ratio (NMR) predicts treatment response and is related to treatment side effect severity. Sleep disturbance may be one important side effect, but understanding sleep disturbance effects on smoking cessation is complicated by the fact that nicotine withdrawal also produces sleep disturbance. To evaluate the effects of withdrawal and treatment side effects on sleep disturbance. This is a secondary analysis of data from a clinical trial (Lerman et al., 2015) of 1,136 smokers randomised to placebo ( n = 363), transdermal nicotine (TN; n = 381), or varenicline ( n = 392) and stratified based on NMR (559 slow metabolisers; 577 normal metabolisers). Sleep disturbance was assessed at baseline and at 1-week following the target quit date (TQD). We also examined whether sleep disturbance predicted 7-day point-prevalence abstinence at end-of-treatment (EOT). The varenicline and TN groups exhibited greater increases in sleep disturbance (vs. placebo; treatment × time interaction; p = 0.005), particularly among those who quit smoking at 1-week post-TQD. There was a main effect of NMR ( p = 0.04), but no interactions with treatment. TN and varenicline attenuated withdrawal symptoms unrelated to sleep (vs. placebo). Greater baseline sleep disturbance predicted relapse at EOT ( p = 0.004). Existing treatments may not mitigate withdrawal-related sleep disturbance and adjunctive treatments that target sleep disturbance may improve abstinence rates.

Lichen Persistence and Recovery in Response to Varied Volcanic Disturbances

Science.gov (United States)

Nelson, P.; Wheeler, T. B.

2015-12-01

Volcanic eruptions produce many ecological disturbances that structure vegetation. While lichens are sensitive to disturbances, little is known about their responses to volcanic disturbances, except for colonization of lava. We examined lichen community responses through time to different disturbances produced by the May 1, 2008 eruption of Volcan Chaiten in south-central Chile. Pre-eruption vegetation near the volcano was old-growth Valdivian temperate rainforest dominated by closed-canopy Nothofagus sp... In 2012, we installed thirteen 1-acre plots across volcanic disturbance zones on which a time-constrained search was done for all macrolichen species, each of which was assigned an approximate log10 categorical abundance. We also installed a 0.2 m2 quadrat on two representative trees per plot for repeat photography of lichen cover. We remeasured at least one plot per disturbance zone in 2014 and re-photographed tree quadrats in 2013 and 2014. We then analyzed species composition and abundance differences among disturbance zones. In 2012, the blast (pyroclastic density flow), scorch (standing scorched forest at the edge of the blast) and deep tephra (>10 cm) zones had the lowest lichen species richness (5-13 species), followed by reference (unimpacted) and shallow (lichen species since 2012 while the light tephra and reference were essentially unchanged. Gravel rain, gravel rain + pumice and flooded forest plots all had about the same number of species in 2014 as 2012. Lichen colonization and growth in tree quadrats varied widely, from very little colonization in the blast to prolific colonization in the gravel rain + pumice zone. Lichen's varied responses to different volcanic disturbances were attributable to varying degrees of mortality and subsequent availability of substrate, quantity of light and removal of competitors. While sensitive to disturbance, lichens are apparently resilient to and can quickly recolonize after a variety of large, violent volcanic

Clinical implications of glycometabolic disturbances in acute coronary

NARCIS (Netherlands)

Timmer, Jorik Rudolf

2005-01-01

Prevalence of glycometabolic disturbances in patients with a suspected acute coronary syndrome is high. One in three patients has signs of disturbed glucose metabolism and this condition is associated with previous or newly diagnosed coronary artery disease. Zie: Summary

Qualitative study of sexual functioning in couples with erectile dysfunction: prospective evaluation of the thermography diagnostic system.

Science.gov (United States)

Ng, Wan Kee; Ng, Yin Kwee; Tan, Yung Khan

2009-01-01

To evaluate the prospective use of the thermography diagnostic system in assessing sexual function in patients with erectile dysfunction (ED). Thermographs were taken on 14 subjects in a clinical trial conducted at Tan Tock Seng Hospital. After a thorough clinical interview with a standardized questionnaire, patients were scanned for baseline temperature profile before being given an oral dose of sildenafil 100 mg. Subjects were scanned again in the same setting an hour later. If so desired, subjects were given visual stimulation and were allowed minimum direct stimulation, excluding the penis, to elicit erection. Temperature profiles were analyzed using the thermography analysis software in the VarioCAM camera. Three representative cases are presented to illustrate the potential for using the Infrared thermography (IR) diagnostic system in differentiating psychogenic ED. IR was able to capture a significant difference in blood flow to the corpus cavernosum. Subjects with psychogenic ED have higher surface temperatures (34.3 degrees C +/- 0.71 in the flaccid state and 35.3 degrees C +/- 0.2 during erection) compared to subjects with organic ED (33.64 degrees C +/- 0.4 in flaccid and 33.55 degrees C +/- 0.91 during erection). The difference in surface temperature between flaccid and erected states in subjects with organic ED was not significant. The proposed diagnostic test based on IR has tremendous clinical potential in differentiating psychogenic ED from organic ED. IR could potentially be a portable, noninvasive and convenient adjunct in the diagnosis and management of ED.

Immediate response of meio and macrobenthos to disturbance caused by a benthic disturber

Digital Repository Service at National Institute of Oceanography (India)

Ingole, B.S.; Ansari, Z.A.; Matondkar, S.G.P.; Rodrigues, N.

The probable impact of nodule mining on benthic biota was studied by creating a benthic disturbance. During the predisturbance study in the Central Indian Basin, box core samples were analyzed for the distribution, composition and abundance...

Mitigating vestibular disturbances during space flight using virtual reality training and reentry vehicle design guidelines

Science.gov (United States)

Stroud, Kenneth Joshua

Seventy to eighty percent of astronauts reportedly exhibit undesirable vestibular disturbances during the first few days of weightlessness, including space motion sickness (SMS) and spatial disorientation (SD). SMS presents a potentially dangerous situation, both because critical piloted tasks such as docking maneuvers and emergency reentry may be compromised, and because of the potential for asphyxiation should an astronaut vomit while wearing a space suit. SD can be provocative for SMS as well as become dangerous during an emergency in which it is critical for an astronaut to move quickly through the vehicle. In the U.S. space program, medication is currently used both for prevention and treatment of SMS. However, this approach has had only moderate success, and the side effects of drowsiness and lack of concentration are undesirable. Research suggests that preflight training in virtual reality devices can simulate certain aspects of microgravity and may prove to be an effective countermeasure for SMS and SD. It was hypothesized that exposing subjects preflight to variable virtual orientations, similar to those encountered during space flight, will reduce the incidence and/or severity of SMS and SD. Results from a study conducted at the NASA Johnson Space Center as part of this research demonstrated that this type of training is effective for reducing motion sickness and improving task performance in potentially disorienting visual surroundings, thus suggesting the possibility that such training may prove an effective countermeasure for SMS, SD and related performance decrements that occur in space flight. In addition to the effects associated with weightlessness, almost all astronauts experience vestibular disturbances associated with gravity-transitions incurred during the return to Earth, which could be exacerbated if traveling in a spacecraft that is designed differently than a conventional aircraft. Therefore, for piloted descent and landing operations

Modelling natural disturbances in forest ecosystems: a review

NARCIS (Netherlands)

Seidl, R.; Fernandes, P.M.; Fonseca, T.F.; Gillet, F.; Jöhnsson, A.M.; Merganičová, K.; Netherer, S.; Arpaci, A.; Bontemps, J.D.; Bugmann, H.; González-Olabarria, J.R.; Lasch, P.; Meredieu, C.; Moreira, F.; Schelhaas, M.; Mohren, G.M.J.

2011-01-01

Natural disturbances play a key role in ecosystem dynamics and are important factors for sustainable forest ecosystem management. Quantitative models are frequently employed to tackle the complexities associated with disturbance processes. Here we review the wide variety of approaches to modelling

Structural Decoupling and Disturbance Rejection in a Distillation Column

DEFF Research Database (Denmark)

Bahar, Mehrdad; Jantzen, Jan; Commault, C.

1996-01-01

Introduction, distillation column model, input-output decoupling, disturbance rejection, concluding remarks, references.......Introduction, distillation column model, input-output decoupling, disturbance rejection, concluding remarks, references....

Restoration of heterogeneous disturbance regimes for the preservation of endangered species

Science.gov (United States)

Steven D. Warren; Reiner Buttner

2014-01-01

Disturbance is a natural component of ecosystems. All species, including threatened and endangered species, evolved in the presence of, and are adapted to natural disturbance regimes that vary in the kind, frequency, severity, and duration of disturbance. We investigated the relationship between the level of visible soil disturbance and the density of four endangered...

Climate mediates the effects of disturbance on ant assemblage structure

Science.gov (United States)

Gibb, Heloise; Sanders, Nathan J.; Dunn, Robert R.; Watson, Simon; Photakis, Manoli; Abril, Silvia; Andersen, Alan N.; Angulo, Elena; Armbrecht, Inge; Arnan, Xavier; Baccaro, Fabricio B.; Bishop, Tom R.; Boulay, Raphael; Castracani, Cristina; Del Toro, Israel; Delsinne, Thibaut; Diaz, Mireia; Donoso, David A.; Enríquez, Martha L.; Fayle, Tom M.; Feener, Donald H.; Fitzpatrick, Matthew C.; Gómez, Crisanto; Grasso, Donato A.; Groc, Sarah; Heterick, Brian; Hoffmann, Benjamin D.; Lach, Lori; Lattke, John; Leponce, Maurice; Lessard, Jean-Philippe; Longino, John; Lucky, Andrea; Majer, Jonathan; Menke, Sean B.; Mezger, Dirk; Mori, Alessandra; Munyai, Thinandavha C.; Paknia, Omid; Pearce-Duvet, Jessica; Pfeiffer, Martin; Philpott, Stacy M.; de Souza, Jorge L. P.; Tista, Melanie; Vasconcelos, Heraldo L.; Vonshak, Merav; Parr, Catherine L.

2015-01-01

Many studies have focused on the impacts of climate change on biological assemblages, yet little is known about how climate interacts with other major anthropogenic influences on biodiversity, such as habitat disturbance. Using a unique global database of 1128 local ant assemblages, we examined whether climate mediates the effects of habitat disturbance on assemblage structure at a global scale. Species richness and evenness were associated positively with temperature, and negatively with disturbance. However, the interaction among temperature, precipitation and disturbance shaped species richness and evenness. The effect was manifested through a failure of species richness to increase substantially with temperature in transformed habitats at low precipitation. At low precipitation levels, evenness increased with temperature in undisturbed sites, peaked at medium temperatures in disturbed sites and remained low in transformed sites. In warmer climates with lower rainfall, the effects of increasing disturbance on species richness and evenness were akin to decreases in temperature of up to 9°C. Anthropogenic disturbance and ongoing climate change may interact in complicated ways to shape the structure of assemblages, with hot, arid environments likely to be at greatest risk. PMID:25994675

Introduction to natural disturbances and historic range of variation: type, frequency, severity, and post-disturbance structure in central hardwood forests

Science.gov (United States)

Katie Greenberg; Beverly S. Collins; Henry McNab; Douglas K. Miller; Gary R. Wein

2015-01-01

EXCERPT FROM: Natural Disturbances and Historic Range Variation 2015. Throughout the history of upland hardwood forests of the Central Hardwood Region, natural disturbances have been integral to shaping forest structure and composition, and essential in maintaining diverse biotic...

Interventions Employed with Students with Emotional Disturbance: A Meta-Analysis

Science.gov (United States)

Wery, Jessica J.

2013-01-01

The purpose of the study was to synthesize research studies that examined interventions used with students with emotional disturbance. Specific goals were to determine the extent to which interventions improve outcomes for students with emotional disturbance, whether emotional disturbance characteristics are related to the effectiveness of…

Features of infrasonic and ionospheric disturbances generated by launch vehicle

International Nuclear Information System (INIS)

Drobzheva, Ya.V.; Krasnov, V.M.; Sokolova, O.I.

2001-01-01

In this paper we present a model, which describe the propagation of acoustic pulses through a model terrestrial atmosphere produced by launch vehicle, and effects of these pulses on the ionosphere above the launch vehicle. We show that acoustic pulses generate disturbances of electron density. The value of these disturbances is about 0.04-0.7% of background electron density. So such disturbances can not create serious noise-free during monitoring of explosions by ionospheric method. We calculated parameters of the blast wave generated at the ionospheric heights by launch vehicle. It was shown that the blast wave is intense and it can generates disturbance of electron density which 2.6 times as much then background electron density. This disturbance is 'cord' with diameter about 150-250 m whereas length of radio line is hundreds and thousand km. Duration of ionospheric disturbances are from 0.2 s to 3-5 s. Such values of duration can not be observed during underground and surface explosions. (author)

Identifying functional groups for response to disturbance in an abandoned pasture

Science.gov (United States)

Lavorel, Sandra; Touzard, Blaise; Lebreton, Jean-Dominique; Clément, Bernard

1998-06-01

In an abandoned pasture in Brittany, we compared artificial small-scale disturbances to natural disturbances by wild boar and undisturbed vegetation. We developed a multivariate statistical approach which analyses how species biological attributes explain the response of community composition to disturbances. This technique, which reconciles the inductive and deductive approaches for functional classifications, identifies groups of species with similar responses to disturbance and characterizes their biological profiles. After 5 months of recolonization, artificial disturbances had a greater species richness than undisturbed vegetation as a result of recruitment of new species without the exclusion of pre-existing matrix species. Species morphology, described by canopy structure, canopy height and lateral spread, explained a large part (16 %) of community response to disturbance. Regeneration strategies, described by life history, seed mass, dispersal agent, dormancy and the existence of vegetative multiplication, explained a smaller part of community response to disturbance (8 %). Artificial disturbances were characterized by therophyte and compact rosettes with moderately dormant seeds, including a number of Asteraceae and other early successional species. Natural disturbances were colonized by leafy guerrilla species without seed dormancy. Few species were tightly related to undisturbed vegetation and were essentially grasses with a phalanx rosette morphology. The functional classification obtained is consistent with the classification of the community into fugitives, regenerators and persistors. These groups are structured according to Grubb's model for temperate grasslands, with regenerators and persistors in the matrix and fugitives taking advantage of gaps open by small-scale disturbances. The conjunction of functional diversity and species diversity within functional groups is the key to resilience to disturbance, an important ecosystem function.

Real-Time Inverse Optimal Neural Control for Image Based Visual Servoing with Nonholonomic Mobile Robots

Directory of Open Access Journals (Sweden)

Carlos López-Franco

2015-01-01

Full Text Available We present an inverse optimal neural controller for a nonholonomic mobile robot with parameter uncertainties and unknown external disturbances. The neural controller is based on a discrete-time recurrent high order neural network (RHONN trained with an extended Kalman filter. The reference velocities for the neural controller are obtained with a visual sensor. The effectiveness of the proposed approach is tested by simulations and real-time experiments.

Sleep disturbance induces neuroinflammation and impairment of learning and memory.

Science.gov (United States)

Zhu, Biao; Dong, Yuanlin; Xu, Zhipeng; Gompf, Heinrich S; Ward, Sarah A P; Xue, Zhanggang; Miao, Changhong; Zhang, Yiying; Chamberlin, Nancy L; Xie, Zhongcong

2012-12-01

Hospitalized patients can develop cognitive function decline, the mechanisms of which remain largely to be determined. Sleep disturbance often occurs in hospitalized patients, and neuroinflammation can induce learning and memory impairment. We therefore set out to determine whether sleep disturbance can induce neuroinflammation and impairment of learning and memory in rodents. Five to 6-month-old wild-type C57BL/6J male mice were used in the studies. The mice were placed in rocking cages for 24 h, and two rolling balls were present in each cage. The mice were tested for learning and memory function using the Fear Conditioning Test one and 7 days post-sleep disturbance. Neuroinflammation in the mouse brain tissues was also determined. Of the Fear Conditioning studies at one day and 7 days after sleep disturbance, twenty-four hour sleep disturbance decreased freezing time in the context test, which assesses hippocampus-dependent learning and memory; but not the tone test, which assesses hippocampus-independent learning and memory. Sleep disturbance increased pro-inflammatory cytokine IL-6 levels and induced microglia activation in the mouse hippocampus, but not the cortex. These results suggest that sleep disturbance induces neuroinflammation in the mouse hippocampus, and impairs hippocampus-dependent learning and memory in mice. Pending further studies, these findings suggest that sleep disturbance-induced neuroinflammation and impairment of learning and memory may contribute to the development of cognitive function decline in hospitalized patients. Copyright © 2012 Elsevier Inc. All rights reserved.

[Non-Pharmacological Interventions for Pregnancy-Related Sleep Disturbances].

Science.gov (United States)

Hung, Hsuan-Man; Chiang, Hsiao-Ching

2017-02-01

Most women experience the worse sleep quality of their life during pregnancy and the early postpartum period. Although pregnancy typically accounts for a relatively short part of a woman's life, the related sleep disturbances may have a significant and negative impact on her long-term health. Approximately 78-80% of pregnant women experience sleep disturbances, including interruptions in deep sleep, decreased total sleep time, poor subjective sleep quality, frequent night waking, and reduced sleep efficacy. Sleep disturbances during pregnancy start during the first trimester and become prevalent during the third trimester. Related factors include physiological and psychosocial changes and an unhealthy lifestyle. As non-pharmacological interventions have the potential to improve sleep quality in 70% to 80% of patients with insomnia, this is the main approached that is currently used to treat pregnancy-related sleep disturbances. Examples of these non-pharmacological interventions include music therapy, aerobic exercise, massage, progressive muscle relaxation, multi-modal interventions, and the use of a maternity support belt. The efficacy and safety of other related non-pharmacological interventions such as auricular acupressure, cognitive therapy, tai chi, and aromatherapy remain uncertain, with more empirical research required. Additionally, non-pharmacological interventions do not effectively treat sleep disturbances in all pregnant women.

Solar-terrestrial disturbances of June-September 1982, 4

International Nuclear Information System (INIS)

Minakoshi, Hisamitsu; Sinno, Kenji; Nishimuta, Ichizo

1986-01-01

The ionospheric disturbances observed in and around Japan in association with the severe geomagnetic storm occurring on July 14 - 16, 1982 were investigated by using ionospheric total electron content (N t ) data obtained by the ETS-II beacon experiment and F region data obtained by the soundings at the latitude chain of the ionospheric stations situated nearly along 135 deg E. The most remarkable storm effect was of the negative disturbance, which is common at mid-latitudes in summer. The negative disturbance comprises the decreases in N t and peak electron density (N m ) and a marked increase in slab thickness. In addition, the following interesting events were observed during this storm: (1) sharp depressions in N t and N m occurred almost simultaneously in the regions from mid-latitudes to the equatorial latitude within a few hours after the storm sudden commencement (SSC), (2) some positive disturbances in the F region appeared during the recovery phase of the storm, and were prominent during the night at mid-latitudes and during the daytime at low latitudes, and (3) wavelike fluctuations of N t , which indicate the existence of a mediumscale traveling ionospheric disturbance (TID) with a nearly north to south direction of propagation, were observed during the main phase. (author)

Ecstasy use and self-reported disturbances in sleep.

Science.gov (United States)

Ogeil, Rowan P; Rajaratnam, Shantha M W; Phillips, James G; Redman, Jennifer R; Broadbear, Jillian H

2011-10-01

Ecstasy users report a number of complaints after its use including disturbed sleep. However, little is known regarding which attributes of ecstasy use are associated with sleep disturbances, which domains of sleep are affected or which factors may predict those ecstasy users likely to have poor sleep quality and/or excessive daytime sleepiness. This study examined questionnaire responses of social drug users (n = 395) to the Pittsburgh Sleep Quality Index and the Epworth Sleepiness Scale. A significant proportion of ecstasy users (69.5%) had Pittsburgh Sleep Quality Index scores above the threshold used to identify sleep disturbance. Although frequency of ecstasy use did not affect the degree of reported sleep disturbance, participants who used larger amounts of ecstasy had poorer sleep. In addition, participants who perceived harmful consequences arising from their ecstasy use or had experienced remorse following ecstasy use had poorer sleep. Clinically relevant levels of sleep disturbance were still evident after controlling for polydrug use. Risk factors for poor sleep quality were younger age, injury post-ecstasy use and having been told to cut down on ecstasy use. Many ecstasy users report poor sleep quality, which likely contributes to the negative effects reported following ecstasy use. Copyright © 2011 John Wiley & Sons, Ltd.

Assessment of surface and subsurface ground disturbance due to underground mining

International Nuclear Information System (INIS)

Khair, A.W.

1994-01-01

This paper presents highlights of the research carried out at West Virginia University in order to assess surface and subsurface ground disturbance due to longwall mining. Extensive instrumentation and measurements have been made over three longwall mines in northern West Virginia during a three-year period. Various monitoring techniques including full profile borehole extensometer, full profile borehole inclinometers, time domain reflectometry, sonic reflection technique, a unique mechanical grouting method, photographic and visual observations, standard surveying, and water-level measurements were utilized. The paper's emphasis is first on surface ground movement and its impact on integrity of surface ground and structures and second on type and magnitude of subsurface ground movements associated with mine geometry and geology. A subsidence prediction model based on implementation of both mechanisms of ground movement around the excavation and the geologic and geotechnical properties of the rock/coal surrounding the excavation has been developed. 8 refs., 14 figs., 1 tab

Wideband Motion Control by Position and Acceleration Input Based Disturbance Observer

Science.gov (United States)

Irie, Kouhei; Katsura, Seiichiro; Ohishi, Kiyoshi

The disturbance observer can observe and suppress the disturbance torque within its bandwidth. Recent motion systems begin to spread in the society and they are required to have ability to contact with unknown environment. Such a haptic motion requires much wider bandwidth. However, since the conventional disturbance observer attains the acceleration response by the second order derivative of position response, the bandwidth is limited due to the derivative noise. This paper proposes a novel structure of a disturbance observer. The proposed disturbance observer uses an acceleration sensor for enlargement of bandwidth. Generally, the bandwidth of an acceleration sensor is from 1Hz to more than 1kHz. To cover DC range, the conventional position sensor based disturbance observer is integrated. Thus, the performance of the proposed Position and Acceleration input based disturbance observer (PADO) is superior to the conventional one. The PADO is applied to position control (infinity stiffness) and force control (zero stiffness). The numerical and experimental results show viability of the proposed method.

Gastroesophageal reflux disease and vocal disturbances

Directory of Open Access Journals (Sweden)

Maria Aparecida Coelho de Arruda Henry

2011-06-01

Full Text Available CONTEXT: Gastroesophageal reflux disease is a chronic disease in which gastroduodenal contents reflux into the esophagus. The clinical picture of gastroesophageal reflux disease is usually composed by heartburn and regurgitation (typical manifestations. Atypical manifestations (vocal disturbances and asthma may also be complaint. OBJECTIVE: To analyse the clinical, endoscopic, manometric and pHmetric aspects of patients suffering from gastroesophageal reflux disease associated with vocal disturbances. METHODS: Fifty patients with gastroesophageal reflux disease were studied, including 25 with vocal disturbances (group 1 - G1 and 25 without these symptoms (group 2 - G2. All patients were submitted to endoscopy, manometry and esophageal pHmetry (2 probes. The group 1 patients were submitted to videolaryngoscopy. RESULTS: Endoscopic findings: non-erosive reflux disease was observed in 95% of G1 patients and 88% of G2. Videolaryngoscopy: vocal fold congestion, asymmetry, nodules and polyps were observed in G1 patients. Manometric findings: pressure in the lower esophageal sphincter (mm Hg: 11.6 ± 5.2 in G1 and 14.0 ± 6.2 in G2 (P = 0.14; pressure in the upper esophageal sphincter (mm Hg: 58.4 ± 15.9 in G1 and 69.5 ± 30.7 in the controls. pHmetric findings: De Meester index: 34.0 ± 20.9 in G1 and 15.4 ± 9.4 in G2 (P<0.001; number of reflux episodes in distal probe: 43.0 ± 20.4 in G1 and 26.4 ± 17.2 in G2 (P = 0.003; percentage of time with esophageal pH value lower than 4 units (distal sensor: 9.0% ± 6.4% in G1 and 3.4% ± 2.1% in G2 (P<0.001; number of reflux episodes in proximal probe: 7.5 ± 10.9 in G1 and 5.3 ± 5.7 in G2 (P = 0.38; percentage of time with esophageal pH values lower than 4 units (Proximal probe: 1.2 ± 2.7 in G1 and 0.5 ± 0.7 in G2 (P = 0.21. CONCLUSIONS: 1 The clinical, endoscopic, and manometric findings observed in patients with vocal disturbance do not differ from those without these symptoms; 2 gastroesophageal

A meta-analysis of human disturbance impacts on Antarctic wildlife.

Science.gov (United States)

Coetzee, Bernard W T; Chown, Steven L

2016-08-01

Evidence-based assessments are increasingly recognized as the best-practice approach to determine appropriate conservation interventions, but such assessments of the impact of human disturbance on wildlife are rare. Human disturbance comprises anthropogenic activities that are typically non-lethal, but may cause short- and/or longer-term stress and fitness responses in wildlife. Expanding human activity in the Antarctic region is of particular concern because it increases the scope and potential for increased human disturbance to wildlife in a region that is often thought of as relatively untouched by anthropogenic influences. Here, we use a meta-analytical approach to synthesise research on human disturbance to wildlife over the last three decades in the Antarctic and sub-Antarctic region. We combine data from 62 studies across 21 species on the behavioural, physiological and population responses of wildlife to pedestrian, vehicle and research disturbances. The overall effect size indicated a small, albeit statistically significant negative effect of disturbance (-0.39; 95% CI: -0.60 to -0.18). Negative effects were found for both physiological and population responses, but no evidence was found for a significant impact on wildlife behavioural responses. Negative effects were found across pedestrian, vehicle and research disturbances. Significant and high among-study heterogeneity was found in both disturbance and response sub-groups. Among species, it remains unclear to what extent different forms of disturbance translate into negative population responses. Most current guidelines to limit wildlife disturbance impacts in Antarctica recommend that approaches be tailored to animal behavioural cues, but our work demonstrates that behavioural changes do not necessarily reflect more cryptic, and more deleterious impacts, such as changes in physiology. In consequence, we recommend that pedestrian approach guidelines in the Antarctic region be revisited. Due to the high

[A case of combined sensation disturbance and clumsiness of the left hand caused by an infarction localized to brodmann areas 1 and 2].

Science.gov (United States)

Kutoku, Yumiko; Hagiwara, Hiroki; Ichikawa, Yaeko; Takeda, Katsuhiko; Sunada, Yoshihide

2007-04-01

A 70-year-old woman was admitted to our hospital with a complaint of numbness and clumsiness of the left hand. On physical examination 23 days after the onset of cerebral infarction, she showed no apparent muscle weakness. Although her elementary somatosensory function was mostly intact with a minimal joint position sensation disturbance, she showed disturbances in tactile recognition, two-point discrimination, and weight perception. She also had difficulty in discrete finger movement of her left hand, especially when her eyes were closed. Brain MRI disclosed a small infarction localized to Brodmann areas 1 and 2 in the right postcentral gyrus. In the left median nerve short-latency somatosensory evoked potentials (s-SEPs), the N20 potential was normally evoked. This finding also indicated that the area 3b was preserved. The sensory symptoms observed in this patient were compatible with the hierarchical somatosensory processing model in the postcentral gyrus proposed by Iwamura et al, in which the elementary sensation recognized in area 3 is transferred to areas 1 and 2, and then processed to discriminative sensation. The disturbed discrete finger movement in this patient probably resulted from impaired tactile recognition which could be compensated for by visual information.

Remote sensing of forest insect disturbances: Current state and future directions.

Science.gov (United States)

Senf, Cornelius; Seidl, Rupert; Hostert, Patrick

2017-08-01

Insect disturbance are important agents of change in forest ecosystems around the globe, yet their spatial and temporal distribution and dynamics are not well understood. Remote sensing has gained much attention in mapping and understanding insect outbreak dynamics. Consequently, we here review the current literature on the remote sensing of insect disturbances. We suggest to group studies into three insect types: bark beetles, broadleaved defoliators, and coniferous defoliators. By so doing, we systematically compare the sensors and methods used for mapping insect disturbances within and across insect types. Results suggest that there are substantial differences between methods used for mapping bark beetles and defoliators, and between methods used for mapping broadleaved and coniferous defoliators. Following from this, we highlight approaches that are particularly suited for each insect type. Finally, we conclude by highlighting future research directions for remote sensing of insect disturbances. In particular, we suggest to: 1) Separate insect disturbances from other agents; 2) Extend the spatial and temporal domain of analysis; 3) Make use of dense time series; 4) Operationalize near-real time monitoring of insect disturbances; 5) Identify insect disturbances in the context of coupled human-natural systems; and 6) Improve reference data for assessing insect disturbances. Since the remote sensing of insect disturbances has gained much interest beyond the remote sensing community recently, the future developments identified here will help integrating remote sensing products into operational forest management. Furthermore, an improved spatiotemporal quantification of insect disturbances will support an inclusion of these processes into regional to global ecosystem models.

Neurobiological basis of parenting disturbance.

Science.gov (United States)

Newman, Louise K; Harris, Melissa; Allen, Joanne

2011-02-01

It has been proposed that early attachment relationships shape the structure and reactivity of social brain structures that underlie later social capacities. We provide a review of the literature surrounding the development of neurological regulatory systems during infancy and outline recent research suggesting these systems go on to underlie adaptive parental responses. We review evidence in the peer-reviewed psychiatric literature including (i) observational human literature on the neurobiological and social sequelae of early parenting experiences, (ii) experimental animal literature on the effects of early maternal care on neurological development, (iii) experimental animal literature on the neurobiological underpinnings of parenting behaviours, (iv) observational and fMRI evidence on the neurobiological correlates of parenting behaviours, (v) functional and volumetric imaging studies on adults affected by borderline personality disorder. The development of infant regulatory systems is influenced by early parenting experiences. These frontolimbic regulatory systems are also heavily implicated in normal parental responses to infant cues. These frontolimbic disturbances are also observed in studies of borderline personality disorder; a disorder associated with poor emotional regulation, early trauma and disturbed parenting. While the current literature is limited to animal models of abnormal care giving, existing disorders associated with deficits in regulatory capacity and abnormal frontolimbic functioning may yet provide a human model of the neurobiology of parenting disturbance.

Patterns of plant species diversity during succession under different disturbance regimes.

Science.gov (United States)

Denslow, Julie Sloan

1980-07-01

I suggest that between-community variations in diversity patterns during succession in plant communities are due to the effects of selection on life history strategies under different disturbance regimes. Natural disturbances to plant communities are simultaneously a source of mortality for some individuals and a source of establishment sites for others. The plant community consists of a mosaic of disturbance patches (gaps) of different environmental conditions. The composition of the mosaic is described by the size-frequency distribution of the gaps and is dependent on the rates and scales of disturbance. The life-history strategies of plant species dependent on some form of disturbance for establishment of propagules should reflect this size-frequency distribution of disturbance patches. An extension of island biogeographic theory to encompass relative habitat area predicts that a community should be most rich in species adapted to growth and establishment in the spatially most common patch types. Changes in species diversity during succession following large scale disturbance reflect the prevalent life history patterns under historically common disturbance regimes. Communities in which the greatest patch area is in large-scale clearings (e.g. following fire) are most diverse in species establishing seedlings in xeric, high light conditions. Species diversity decreases during succession. Communities in which such large patches are rare are characterized by a large number of species that reach the canopy through small gaps and realtively few which regenerate in the large clearings. Diversity increases during succession following a large scale disturbance.Evidence from communities characterized by different disturbance regimes is summarized from the literature. This hypothesis provides an evolutionary mechanism with which to examine the changes in plant community structure during succession. Diversity peaks occurring at "intermediate levels" of disturbance as

Minimum disturbance rewards with maximum possible classical correlations

Energy Technology Data Exchange (ETDEWEB)

Pande, Varad R., E-mail: varad_pande@yahoo.in [Department of Physics, Indian Institute of Science Education and Research Pune, 411008 (India); Shaji, Anil [School of Physics, Indian Institute of Science Education and Research Thiruvananthapuram, 695016 (India)

2017-07-12

Weak measurements done on a subsystem of a bipartite system having both classical and nonClassical correlations between its components can potentially reveal information about the other subsystem with minimal disturbance to the overall state. We use weak quantum discord and the fidelity between the initial bipartite state and the state after measurement to construct a cost function that accounts for both the amount of information revealed about the other system as well as the disturbance to the overall state. We investigate the behaviour of the cost function for families of two qubit states and show that there is an optimal choice that can be made for the strength of the weak measurement. - Highlights: • Weak measurements done on one part of a bipartite system with controlled strength. • Weak quantum discord & fidelity used to quantify all correlations and disturbance. • Cost function to probe the tradeoff between extracted correlations and disturbance. • Optimal measurement strength for maximum extraction of classical correlations.

Biomarker responses of mussels exposed to earthquake disturbances

Science.gov (United States)

Chandurvelan, Rathishri; Marsden, Islay D.; Glover, Chris N.; Gaw, Sally

2016-12-01

The green-lipped mussel, Perna canaliculus is recognised as a bioindicator of coastal contamination in New Zealand (NZ). Mussels (shell length 60-80 mm) were collected from three intertidal areas of Canterbury in the South Island of NZ prior to extreme earthquake disturbances on 22nd February 2011, and 9 months later in October 2011. Trace elements, including arsenic (As), cadmium (Cd), copper (Cu), lead (Pb), nickel (Ni), and zinc (Zn), were measured in the gills, digestive gland, foot and mantle. Metal levels in tissues were site specific, and mostly unaffected by earthquake disturbances. Physiological biomarkers were negatively affected by earthquake disturbances and mussels from the Port of Lyttelton had higher negative scope for growth post-earthquake. Metallothionein-like protein in the digestive gland correlated with metal content of tissues, as did catalase activity in the gill and lipid peroxidation values for the digestive gland. This research demonstrates that physiological and other biomarkers are effective at detecting the effects of multiple stressors following seismic disturbances.

Sensitivity of climate mitigation strategies to natural disturbances

International Nuclear Information System (INIS)

Le Page, Y; Hurtt, G; Thomson, A M; Bond-Lamberty, B; Patel, P; Wise, M; Calvin, K; Kyle, P; Clarke, L; Edmonds, J; Janetos, A

2013-01-01

The present and future concentration of atmospheric carbon dioxide depends on both anthropogenic and natural sources and sinks of carbon. Most proposed climate mitigation strategies rely on a progressive transition to carbon-efficient technologies to reduce industrial emissions, substantially supported by policies to maintain or enhance the terrestrial carbon stock in forests and other ecosystems. This strategy may be challenged if terrestrial sequestration capacity is affected by future climate feedbacks, but how and to what extent is little understood. Here, we show that climate mitigation strategies are highly sensitive to future natural disturbance rates (e.g. fires, hurricanes, droughts), because of the potential effect of disturbances on the terrestrial carbon balance. Generally, altered disturbance rates affect the pace of societal and technological transitions required to achieve the mitigation target, with substantial consequences on the energy sector and the global economy. An understanding of the future dynamics and consequences of natural disturbances on terrestrial carbon balance is thus essential for developing robust climate mitigation strategies and policies. (letter)

Ionospheric irregularities in periods of meteorological disturbances

Science.gov (United States)

Borchevkina, O. P.; Karpov, I. V.

2017-09-01

The results of observations of the total electron content (TEC) in periods of storm disturbances of meteorological situation are presented in the paper. The observational results have shown that a passage of a meteorological storm is accompanied by a substantial decrease in values of TEC and critical frequencies of the ionospheric F2 region. The decreases in values of these ionospheric parameters reach 50% and up to 30% in TEC and critical frequency of the F2 layer, respectively, as compared to meteorologically quiet days. Based on qualitative analysis, it is found that the processes related to formation of local regions of thermospheric heating due to a dissipation of AGW coming into the upper atmosphere from the region of the meteorological disturbance in the lower atmosphere are a possible cause of these ionospheric disturbances.

Stress, coping, and disturbed eating attitudes in teenage girls.

Science.gov (United States)

Fryer, S; Waller, G; Kroese, B S

1997-12-01

This study explored the relationship between stressors and disturbed eating attitudes among adolescent females, assessing the moderating role of coping and the mediating influence of poor self-esteem. Two hundred eighty-six teenage girls were recruited from local schools, and completed standardized measures of stressors, coping, self-esteem, perfectionism, and disturbed eating attitudes. Regression analyses were used to test for moderating and mediating effects. Stressors and emotion-focused coping were found to be associated with low self-esteem, which in turn was strongly associated with disturbed eating attitudes. Stressors were also directly related to disturbed eating attitudes. The findings provide partial support for existing models of the etiology and maintenance of eating psychopathology, but have wider implications for our understanding of the eating disorders and their treatment.

Biweekly disturbance capture and attribution: case study in western Alberta grizzly bear habitat

Science.gov (United States)

Hilker, Thomas; Coops, Nicholas C.; Gaulton, Rachel; Wulder, Michael A.; Cranston, Jerome; Stenhouse, Gordon

2011-01-01

An increasing number of studies have demonstrated the impact of landscape disturbance on ecosystems. Satellite remote sensing can be used for mapping disturbances, and fusion techniques of sensors with complimentary characteristics can help to improve the spatial and temporal resolution of satellite-based mapping techniques. Classification of different disturbance types from satellite observations is difficult, yet important, especially in an ecological context as different disturbance types might have different impacts on vegetation recovery, wildlife habitats, and food resources. We demonstrate a possible approach for classifying common disturbance types by means of their spatial characteristics. First, landscape level change is characterized on a near biweekly basis through application of a data fusion model (spatial temporal adaptive algorithm for mapping reflectance change) and a number of spatial and temporal characteristics of the predicted disturbance patches are inferred. A regression tree approach is then used to classify disturbance events. Our results show that spatial and temporal disturbance characteristics can be used to classify disturbance events with an overall accuracy of 86% of the disturbed area observed. The date of disturbance was identified as the most powerful predictor of the disturbance type, together with the patch core area, patch size, and contiguity.

Soldier-worn augmented reality system for tactical icon visualization

Science.gov (United States)

Roberts, David; Menozzi, Alberico; Clipp, Brian; Russler, Patrick; Cook, James; Karl, Robert; Wenger, Eric; Church, William; Mauger, Jennifer; Volpe, Chris; Argenta, Chris; Wille, Mark; Snarski, Stephen; Sherrill, Todd; Lupo, Jasper; Hobson, Ross; Frahm, Jan-Michael; Heinly, Jared

2012-06-01

This paper describes the development and demonstration of a soldier-worn augmented reality system testbed that provides intuitive 'heads-up' visualization of tactically-relevant geo-registered icons. Our system combines a robust soldier pose estimation capability with a helmet mounted see-through display to accurately overlay geo-registered iconography (i.e., navigation waypoints, blue forces, aircraft) on the soldier's view of reality. Applied Research Associates (ARA), in partnership with BAE Systems and the University of North Carolina - Chapel Hill (UNC-CH), has developed this testbed system in Phase 2 of the DARPA ULTRA-Vis (Urban Leader Tactical, Response, Awareness, and Visualization) program. The ULTRA-Vis testbed system functions in unprepared outdoor environments and is robust to numerous magnetic disturbances. We achieve accurate and robust pose estimation through fusion of inertial, magnetic, GPS, and computer vision data acquired from helmet kit sensors. Icons are rendered on a high-brightness, 40°×30° field of view see-through display. The system incorporates an information management engine to convert CoT (Cursor-on-Target) external data feeds into mil-standard icons for visualization. The user interface provides intuitive information display to support soldier navigation and situational awareness of mission-critical tactical information.

Effects of intermediate-scale wind disturbance on composition, structure, and succession in Quercus stands: Implications for natural disturbance-based silviculture

Science.gov (United States)

M.M. Cowden; J.L. Hart; C.J. Schweitzer; D.C. Dey

2014-01-01

Forest disturbances are discrete events in space and time that disrupt the biophysical environment and impart lasting legacies on forest composition and structure. Disturbances are often classified along a gradient of spatial extent and magnitude that ranges from catastrophic events where most of the overstory is removed to gap-scale events that modify local...

Organic and Non-Organic Language Disorders after Awake Brain Surgery

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Elke De Witte

2014-04-01

Full Text Available INTRODUCTION: Awake surgery with Direct Electrical Stimulation (DES is considered the ‘gold standard’ to resect brain tumours in the language dominant hemisphere (De Witte & Mariën, 2013. Although transient language impairments are common in the immediate postoperative phase, permanent postoperative language deficits seem to be rare (Duffau, 2007. Milian et al. (2014 stated that most patients tolerate the awake procedure well and would undergo a similar procedure again. However, postoperative psychological symptoms including recurrent distressing dreams and persistent avoidance of stimuli have been recorded following awake surgery (Goebel, Nabavi, Schubert, & Mehdorn, 2010; Milian et al., 2014. To the best of our knowledge, psychogenic language disturbances have never been described after awake surgery. In general, only a handful of non-organic, psychogenic language disorders have been reported in the literature (De Letter et al., 2012. We report three patients with left brain tumours (see table 1 who presented linguistic symptoms after awake surgery that were incompatible with the lesion location, suggesting a psychogenic origin. METHODS: Neurocognitive (language, memory, executive functions investigations were carried out before, during and after awake surgery (6 weeks, 6 months postsurgery on the basis of standardised tests. Pre- and postoperative (fMRI images, DTI results and intraoperative DES findings were analysed. A selection of tasks was used to map language intraoperatively (De Witte et al., 2013. In the postoperative phase spontaneous speech and behavioural phenomena to errors were video-recorded. RESULTS: Preoperative language tests did not reveal any speech or language problems. Intraoperatively, eloquent sites were mapped and preserved enabling good language skills at the end of the awake procedure. However, assessments in the first weeks postsurgery disclosed language and behavioural symptoms that support the hypothesis of a

Mapping forest canopy disturbance in the Upper Great Lakes, USA

Science.gov (United States)

James D. Garner; Mark D. Nelson; Brian G. Tavernia; Charles H. (Hobie) Perry; Ian W. Housman

2015-01-01

A map of forest canopy disturbance was generated for Michigan, Wisconsin, and most of Minnesota using 42 Landsat time series stacks (LTSS) and a vegetation change tracker (VCTw) algorithm. Corresponding winter imagery was used to reduce commission errors of forest disturbance by identifying areas of persistent snow cover. The resulting disturbance age map was classed...

Robust Predictive Functional Control for Flight Vehicles Based on Nonlinear Disturbance Observer

Directory of Open Access Journals (Sweden)

Yinhui Zhang

2015-01-01

Full Text Available A novel robust predictive functional control based on nonlinear disturbance observer is investigated in order to address the control system design for flight vehicles with significant uncertainties, external disturbances, and measurement noise. Firstly, the nonlinear longitudinal dynamics of the flight vehicle are transformed into linear-like state-space equations with state-dependent coefficient matrices. And then the lumped disturbances are considered in the linear structure predictive model of the predictive functional control to increase the precision of the predictive output and resolve the intractable mismatched disturbance problem. As the lumped disturbances cannot be derived or measured directly, the nonlinear disturbance observer is applied to estimate the lumped disturbances, which are then introduced to the predictive functional control to replace the unknown actual lumped disturbances. Consequently, the robust predictive functional control for the flight vehicle is proposed. Compared with the existing designs, the effectiveness and robustness of the proposed flight control are illustrated and validated in various simulation conditions.

Disturbance estimation of nuclear power plant by using reduced-order model

International Nuclear Information System (INIS)

Tashima, Shin-ichi; Wakabayashi, Jiro

1983-01-01

An estimation method is proposed of multiplex disturbances which occur in a nuclear power plant. The method is composed of two parts: (i) the identification of a simplified model of multi-input and multi-output to describe the related system response, and (ii) the design of a Kalman filter to estimate the multiplex disturbance. Concerning the simplified model, several observed signals are firstly selected as output variables which can well represent the system response caused by the disturbances. A reduced-order model is utilized for designing the disturbance estimator. This is based on the following two considerations. The first is that the disturbance is assumed to be of a quasistatic nature. The other is based on the intuition that there exist a few dominant modes between the disturbances and the selected observed signals and that most of the non-dominant modes which remain may not affect the accuracy of the disturbance estimator. The reduced-order model is furtherly transformed to a single-output model using a linear combination of the output signals, where the standard procedure of the structural identification is evaded. The parameters of the model thus transformed are calculated by the generalized least square method. As for the multiplex disturbance estimator, the Kalman filtering method is applied by compromising the following three items : (a) quick response to disturbance, (b) reduction of estimation error in the presence of observation noises, and (c) the elimination of cross-interference between the disturbances to the plant and the estimates from the Kalman filter. The effectiveness of the proposed method is verified through some computer experiments using a BWR plant simulator. (author)

Robust Consensus of Multi-Agent Systems with Uncertain Exogenous Disturbances

International Nuclear Information System (INIS)

Yang Hong-Yong; Guo Lei; Han Chao

2011-01-01

The objective of this paper is to investigate the consensus of the multi-agent systems with nonlinear coupling function and external disturbances. The disturbance includes two parts, one part is supposed to be generated by an exogenous system, which is not required to be neutrally stable as in the output regulation theory, the other part is the modeling uncertainty in the exogenous disturbance system. A novel composite disturbance observer based control (DOBC) and H ∞ control scheme is presented so that the disturbance with the exogenous system can be estimated and compensated and the consensus of the multi-agent systems with fixed and switching graph can be reached by using H ∞ control law. Simulations demonstrate the advantages of the proposed DOBC and H ∞ control scheme. (interdisciplinary physics and related areas of science and technology)

PERFUGIA AS A MECHANISM FOR THE RECOVERY OF SOIL FAUNA AFTER ECOSYSTEM DISTURBANCES

Directory of Open Access Journals (Sweden)

K. B. Gongalsky

2017-12-01

Full Text Available Disturbances such as forest fires, industrial pollution, etc. are almost always heterogeneous, leaving less disturbed patches within the boundaries of disturbances. In addition to the traditionally considered source of soil invertebrates’ restoration by immigration from the surrounding unchanged biotopes, the role of locally undisturbed areas within the impact zones is shown. The presence of perfugia within the impact areas of various origin is revealed. Perfugia are locally less disturbed or undisturbed areas within a disturbed ecosystem where specimens or remnants of soil biota communities survive a disturbance. They are characterized by higher diversity and abundance of soil fauna in comparison to the main disturbed area. The heterogeneity of soil environment, the heterogeneity of its disturbance and the presence of perfugia serve as one of the factors in the recovery of soil fauna after the disturbances.

Solar Development on Contaminated and Disturbed Lands

Energy Technology Data Exchange (ETDEWEB)

Macknick, Jordan [National Renewable Energy Lab. (NREL), Golden, CO (United States); Lee, Courtney [National Renewable Energy Lab. (NREL), Golden, CO (United States); Mosey, Gail [National Renewable Energy Lab. (NREL), Golden, CO (United States); Melius, Jenny [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2013-12-01

Land classified as contaminated and disturbed across the United States has the potential to host developments of utility-scale solar power. This report examines the prospect of developing utility- and commercial-scale concentrated solar power (CSP) and solar photovoltaics (PV) technologies on degraded and environmentally contaminated lands. The potential for solar development on contaminated anddisturbed lands was assessed, and for the largest and highest solar resource sites, the economic impacts and feasibility were evaluated. Developing solar power on contaminated and disturbed lands can help create jobs and revitalize local and state economies, and selecting these sites over greenfield sites can potentially have permitting and environmental mitigation advantages. The U.S.Department of Energy (DOE) SunShot goals call for 632 GW of PV and 83 GW of CSP to be deployed by 2050. Conservative land-use estimates of this study (10 acres per megawatt) show that there are disturbed and environmentally contaminated lands throughout the country that could be suitable for utility-scale solar power, and, that there is sufficient land area to meet SunShot solar deployment goals. The purpose of this assessment is to improve the understanding of these sites and facilitate solar developers' selection of contaminated and disturbed sites for development.

Forest disturbance by an ecosystem engineer: beaver in boreal forest landscapes

OpenAIRE

Nummi, Petri; Kuuluvainen, Timo

2013-01-01

Natural disturbances are important for forest ecosystem dynamics and maintenance of biodiversity. In the boreal forest, large-scale disturbances such as wildfires and windstorms have been emphasized, while disturbance agents acting at smaller scales have received less attention. Especially in Europe beavers have long been neglected as forest disturbance agents because they were extirpated from most of their range centuries ago. However, now they are returning to many parts of their former dis...

Design and Application of Offset-Free Model Predictive Control Disturbance Observation Method

Directory of Open Access Journals (Sweden)

Xue Wang

2016-01-01

Full Text Available Model predictive control (MPC with its lower request to the mathematical model, excellent control performance, and convenience online calculation has developed into a very important subdiscipline with rich theory foundation and practical application. However, unmeasurable disturbance is widespread in industrial processes, which is difficult to deal with directly at present. In most of the implemented MPC strategies, the method of incorporating a constant output disturbance into the process model is introduced to solve this problem, but it fails to achieve offset-free control once the unmeasured disturbances access the process. Based on the Kalman filter theory, the problem is solved by using a more general disturbance model which is superior to the constant output disturbance model. This paper presents the necessary conditions for offset-free model predictive control based on the model. By applying disturbance model, the unmeasurable disturbance vectors are augmented as the states of control system, and the Kalman filer is used to estimate unmeasurable disturbance and its effect on the output. Then, the dynamic matrix control (DMC algorithm is improved by utilizing the feed-forward compensation control strategy with the disturbance estimated.

Are sleep disturbances preclinical markers of Parkinson’s disease?

DEFF Research Database (Denmark)

Brito dos Santos, Altair; Kohlmeier, Kristi Anne; Barreto, George

2015-01-01

REM sleep behaviour and currently several other disturbances have gained importance as potential markers, such as excessive daytime sleepiness, restless legs syndrome and new evidence also points to changes in circadian rhythms. Here we present a brief review of the major evidence indicating......Parkinson’s disease (PD) is a neurobehavioral disorder characterized by motor symptoms and signs, and non-motor abnormalities such as olfactory dysfunction, pain, sleep disorders and cognitive impairment. Amongst these alterations, sleep disturbances play an important role in the pathology......, but presence of disturbed sleep is not currently considered in diagnosis. However, sleeping problems may precede by many years the classic motor abnormalities of PD and should be clinically evaluated as a potential marker before disease onset. The first disturbance reported with this potential was the disorder...

On the centrality of disturbance rejection in automatic control.

Science.gov (United States)

Gao, Zhiqiang

2014-07-01

In this paper, it is shown that the problem of automatic control is, in essence, that of disturbance rejection, with the notion of disturbance generalized to symbolize the uncertainties, both internal and external to the plant. A novel, unifying concept of disturbance rejector is proposed to compliment the traditional notion of controller. The new controller-rejector pair is shown to be a powerful organizing principle in the realm of automatic control, leading to a Copernican moment where the model-centric design philosophy is replaced by the one that is control-centric in the following sense: the controller is designed for a canonical model and is fixed; the difference between the plant and the canonical model is deemed as disturbance and rejected. © 2013 ISA. Published by Elsevier Ltd. All rights reserved.

Smith predictor-based multiple periodic disturbance compensation for long dead-time processes

Science.gov (United States)

Tan, Fang; Li, Han-Xiong; Shen, Ping

2018-05-01

Many disturbance rejection methods have been proposed for processes with dead-time, while these existing methods may not work well under multiple periodic disturbances. In this paper, a multiple periodic disturbance rejection is proposed under the Smith predictor configuration for processes with long dead-time. One feedback loop is added to compensate periodic disturbance while retaining the advantage of the Smith predictor. With information of the disturbance spectrum, the added feedback loop can remove multiple periodic disturbances effectively. The robust stability can be easily maintained through the rigorous analysis. Finally, simulation examples demonstrate the effectiveness and robustness of the proposed method for processes with long dead-time.

Mapping disturbance dynamics in wet sclerophyll forests using time series Landsat

NARCIS (Netherlands)

Haywood, A.; Verbesselt, J.; Baker, P.J.

2016-01-01

In this study, we characterised the temporal-spectral patterns associated with identifying acute-severity disturbances and low-severity disturbances between 1985 and 2011 with the objective to test whether different disturbance agents within these categories can be identified with annual Landsat

Ensemble modeling to predict habitat suitability for a large-scale disturbance specialist

Science.gov (United States)

Quresh S. Latif; Victoria A. Saab; Jonathan G. Dudley; Jeff P. Hollenbeck

2013-01-01

To conserve habitat for disturbance specialist species, ecologists must identify where individuals will likely settle in newly disturbed areas. Habitat suitability models can predict which sites at new disturbances will most likely attract specialists. Without validation data from newly disturbed areas, however, the best approach for maximizing predictive accuracy can...

Attachment style, relationship quality, and psychological distress in patients with psychogenic non-epileptic seizures versus epilepsy.

Science.gov (United States)

Green, Becky; Norman, Paul; Reuber, Markus

2017-01-01

Psychopathology levels are elevated in patients with psychogenic non-epileptic seizures (PNES) and those with epilepsy. However, patients with PNES report higher rates of trauma and neglect, poorer health-related quality of life (HRQoL), and an increased prevalence of insecure attachment. We examined to what extent attachment style and relationship quality with their main informal carer impact on levels of HRQoL, depression, and anxiety in patients with PNES versus those with epilepsy. Consecutive patients with PNES (N=23) and epilepsy (N=72) completed questionnaires about attachment style, quality of their relationship with their main informal carer, seizure severity, HRQoL, depression, and anxiety. Patients with PNES reported higher levels of anxiety and depression and lower HRQoL than those with epilepsy. PNES: No significant correlations were found with HRQoL but depression correlated positively with attachment avoidance, attachment anxiety, and relationship conflict. Anxiety correlated positively with attachment avoidance, attachment anxiety, and relationship conflict, and negatively with relationship depth and support. Epilepsy: HRQoL correlated negatively with seizure severity, depression, anxiety, attachment avoidance, and attachment anxiety. Depression correlated positively with attachment avoidance, attachment anxiety, and relationship conflict. Anxiety correlated positively with seizure severity, attachment avoidance, and attachment anxiety. Correlations between measures of relationship quality and anxiety were stronger in patients with PNES versus those with epilepsy (zs=2.66 to 2.97, ps<0.004). Attachment style and relationship quality explained larger amounts of variance in depression (45%) and anxiety (60%) in the patients with PNES than those with epilepsy (16% and 13%). Levels of anxiety and depression were higher in patients with PNES than those with epilepsy. Interpersonal problems were much more closely associated with anxiety and depression in

ALSAN - A system for disturbance analysis by process computers

International Nuclear Information System (INIS)

Felkel, L.; Grumbach, R.

1977-05-01

The program system ALSAN has been developed to process the large number of signals due to a disturbance in a complex technical process, to recognize the important (in order to settle the disturbance within a minimum amount of time) information, and to display it to the operators. By means of the results, clear decisions can be made on what counteractions have to be taken. The system works in on-line-open-loop mode, and analyses disturbances autonomously as well as in dialog with the operators. (orig.) [de

Aging of non-visual spectral sensitivity to light in humans: compensatory mechanisms?

Directory of Open Access Journals (Sweden)

Raymond P Najjar

Full Text Available The deterioration of sleep in the older population is a prevalent feature that contributes to a decrease in quality of life. Inappropriate entrainment of the circadian clock by light is considered to contribute to the alteration of sleep structure and circadian rhythms in the elderly. The present study investigates the effects of aging on non-visual spectral sensitivity to light and tests the hypothesis that circadian disturbances are related to a decreased light transmittance. In a within-subject design, eight aged and five young subjects were exposed at night to 60 minute monochromatic light stimulations at 9 different wavelengths (420-620 nm. Individual sensitivity spectra were derived from measures of melatonin suppression. Lens density was assessed using a validated psychophysical technique. Although lens transmittance was decreased for short wavelength light in the older participants, melatonin suppression was not reduced. Peak of non-visual sensitivity was, however, shifted to longer wavelengths in the aged participants (494 nm compared to young (484 nm. Our results indicate that increased lens filtering does not necessarily lead to a decreased non-visual sensitivity to light. The lack of age-related decrease in non-visual sensitivity to light may involve as yet undefined adaptive mechanisms.

Nonlinear Robust Control of a Hypersonic Flight Vehicle Using Fuzzy Disturbance Observer

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Lei Zhengdong

2013-01-01

Full Text Available This paper is concerned with a novel tracking controller design for a hypersonic flight vehicle in complex and volatile environment. The attitude control model is challengingly constructed with multivariate uncertainties and external disturbances, such as structure dynamic and stochastic wind disturbance. In order to resist the influence of uncertainties and disturbances on the flight control system, nonlinear disturbance observer is introduced to estimate them. Moreover, for the sake of high accuracy and sensitivity, fuzzy theory is adopted to improve the performance of the nonlinear disturbance observer. After the total disturbance is eliminated by dynamic inversion method, a cascade system is obtained and then stabilized by a sliding-mode controller. Finally, simulation results show that the strong robust controller achieves excellent performance when the closed-loop control system is influenced by mass uncertainties and external disturbances.

Combined Power Quality Disturbances Recognition Using Wavelet Packet Entropies and S-Transform

Directory of Open Access Journals (Sweden)

Zhigang Liu

2015-08-01

Full Text Available Aiming at the combined power quality +disturbance recognition, an automated recognition method based on wavelet packet entropy (WPE and modified incomplete S-transform (MIST is proposed in this paper. By combining wavelet packet Tsallis singular entropy, energy entropy and MIST, a 13-dimension vector of different power quality (PQ disturbances including single disturbances and combined disturbances is extracted. Then, a ruled decision tree is designed to recognize the combined disturbances. The proposed method is tested and evaluated using a large number of simulated PQ disturbances and some real-life signals, which include voltage sag, swell, interruption, oscillation transient, impulsive transient, harmonics, voltage fluctuation and their combinations. In addition, the comparison of the proposed recognition approach with some existing techniques is made. The experimental results show that the proposed method can effectively recognize the single and combined PQ disturbances.

Timing is everything: priority effects alter community invasibility after disturbance.

Science.gov (United States)

Symons, Celia C; Arnott, Shelley E

2014-02-01

Theory suggests that communities should be more open to the establishment of regional species following disturbance because disturbance may make more resources available to dispersers. However, after an initial period of high invasibility, growth of the resident community may lead to the monopolization of local resources and decreased probability of successful colonist establishment. During press disturbances (i.e., directional environmental change), it remains unclear what effect regional dispersal will have on local community structure if the establishment of later arriving species is affected by early arriving species (i.e., if priority effects are important). To determine the relationship between time-since-disturbance and invasibility, we conducted a fully factorial field mesocosm experiment that exposed tundra zooplankton communities to two emerging stressors - nutrient and salt addition, and manipulated the arrival timing of regional dispersers. Our results demonstrate that invasibility decreases with increasing time-since-disturbance as abundance (nutrient treatments) or species richness (salt treatments) increases in the resident community. Results suggest that the relative timing of dispersal and environmental change will modify the importance of priority effects in determining species composition after a press disturbance.

Sleep disturbance and neuropsychological function in young children with ADHD.

Science.gov (United States)

Schneider, Heather E; Lam, Janet C; Mahone, E Mark

2016-01-01

Sleep disturbance, common among children with ADHD, can contribute to cognitive and behavioral dysfunction. It is therefore challenging to determine whether neurobehavioral dysfunction should be attributed to ADHD symptoms, sleep disturbance, or both. The present study examined parent-reported sleep problems (Children's Sleep Habits Questionnaire) and their relationship to neuropsychological function in 64 children, aged 4-7 years, with and without ADHD. Compared to typically developing controls, children with ADHD were reported by parents to have significantly greater sleep disturbance--including sleep onset delay, sleep anxiety, night awakenings, and daytime sleepiness--(all p ≤ .01), and significantly poorer performance on tasks of attention, executive control, processing speed, and working memory (all p sleep disturbance was significantly associated with deficits in attention and executive control skills (all p ≤ .01); however, significant group differences (relative to controls) on these measures remained (p sleep disturbance. While sleep problems are common among young children with ADHD, these findings suggest that inattention and executive dysfunction appear to be attributable to symptoms of ADHD rather than to sleep disturbance. The relationships among sleep, ADHD symptoms, and neurobehavioral function in older children may show different patterns as a function of the chronicity of disordered sleep.

Evaluating disturbance on mediterranean karst areas: the example of Sardinia (Italy)

Science.gov (United States)

de Waele, Jo

2009-07-01

Evaluating the human disturbance on karst areas is a difficult task because of the complexity of these peculiar and unique environments. The human impact on karstic geo-ecosystems is increasingly important and there is an increasing need for multidisciplinary tools to assess the environmental changes in karst areas. Many disciplines, such as biology, geomorphology, hydrology and social-economical sciences are to be considered to sufficiently evaluate the impact on these intrinsically vulnerable areas. This article gives an overview of the evolution of environmental impact on karst areas of the island Sardinia (Italy). For this particular case, the most important impacts in the past 50 years are derived from the following activities, in decreasing importance: (1) mining and quarrying; (2) deforestation, agriculture and grazing; (3) building (widespread urbanisation, isolated homes, etc.) and related infrastructures (roads, sewer systems, aqueducts, waste dumps, etc.); (4) tourism; (5) military activities. To evaluate the present environmental state of these areas the Disturbance Index for Karst environments [Van Beynen and Townsend (Environ Manage 36:101-116)] is applied in a slightly modified version. Instead of considering the indicators of environmental disturbances used in the original method, this slightly modified index evaluates the disturbances causing the deterioration of the environmental attributes. In the Sardinian case study, 27 disturbances have been evaluated, giving rise to the definition of a Disturbance Index ranging between 0 (Pristine) and 1 (highly disturbed). This Disturbance Index simplifies the original KDI method, appears to adequately measure disturbance on Mediterranean karst areas and could be applied with success to other similar regions.

An assessment of microbial communities associated with surface mining-disturbed overburden.

Science.gov (United States)

Poncelet, Dominique M; Cavender, Nicole; Cutright, Teresa J; Senko, John M

2014-03-01

To assess the microbiological changes that occur during the maturation of overburden that has been disturbed by surface mining of coal, a surface mining-disturbed overburden unit in southeastern Ohio, USA was characterized. Overburden from the same unit that had been disturbed for 37 and 16 years were compared to undisturbed soil from the same region. Overburden and soil samples were collected as shallow subsurface cores from each subregion of the mined area (i.e., land 16 years and 37 years post-mining, and unmined land). Chemical and mineralogical characteristics of overburden samples were determined, as were microbial respiration rates. The composition of microbial communities associated with overburden and soil were determined using culture-independent, nucleic acid-based approaches. Chemical and mineralogical evaluation of overburden suggested that weathering of disturbed overburden gave rise to a setting with lower pH and more oxidized chemical constituents. Overburden-associated microbial biomass and respiration rates increased with time after overburden disturbance. Evaluation of 16S rRNA gene libraries that were produced by "next-generation" sequencing technology revealed that recently disturbed overburden contained an abundance of phylotypes attributable to sulfur-oxidizing Limnobacter spp., but with increasing time post-disturbance, overburden-associated microbial communities developed a structure similar to that of undisturbed soil, but retained characteristics of more recently disturbed overburden. Our results indicate that over time, the biogeochemical weathering of disturbed overburden leads to the development of geochemical conditions and microbial communities that approximate those of undisturbed soil, but that this transition is incomplete after 37 years of overburden maturation.

Movie-maps of low-latitude magnetic storm disturbance

Science.gov (United States)

Love, Jeffrey J.; Gannon, Jennifer L.

2010-06-01

We present 29 movie-maps of low-latitude horizontal-intensity magnetic disturbance for the years 1999-2006: 28 recording magnetic storms and 1 magnetically quiescent period. The movie-maps are derived from magnetic vector time series data collected at up to 25 ground-based observatories. Using a technique similar to that used in the calculation of Dst, a quiet time baseline is subtracted from the time series from each observatory. The remaining disturbance time series are shown in a polar coordinate system that accommodates both Earth rotation and the universal time dependence of magnetospheric disturbance. Each magnetic storm recorded in the movie-maps is different. While some standard interpretations about the storm time equatorial ring current appear to apply to certain moments and certain phases of some storms, the movie-maps also show substantial variety in the local time distribution of low-latitude magnetic disturbance, especially during storm commencements and storm main phases. All movie-maps are available at the U.S. Geological Survey Geomagnetism Program Web site (http://geomag.usgs.gov).

The influence of experimental wind disturbance on forest fuels and fire characteristics

Science.gov (United States)

Jeffery B. Cannon; Joseph J. O' Brien; Louise Loudermilk; Matthew Dickinson; Chris J. Peterson

2014-01-01

Current theory in disturbance ecology predicts that extreme disturbances in rapid succession can lead to dramatic changes in species composition or ecosystem processes due to interactions among disturbances. However, the extent to which less catastrophic, yet chronic, disturbances such as wind damage and fire interact is not well studied. In this study, we simulated...

GMD Coupling to Power Systems and Disturbance Mitigation

Energy Technology Data Exchange (ETDEWEB)

Rivera, Michael Kelly [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Bent, Russell Whitford [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2018-01-24

Presentation includes slides on Geomagnetic Disturbance: Ground Fields; Geomagnetic Disturbance: Coupling to Bulk Electric System; Geomagnetic Disturbance: Transformers; GMD Assessment Workflow (TPL-007-1); FERC order 830; Goals; SuperMag (1 min data) Nov. 20-21, 2003 Storm (DST = -422); Spherical Harmonics; Spherical Harmonics Nov. 20-21, 2003 Storm (DST = -422); DST vs HN0,0; Fluctuations vs. DST; Fluctuations; Conclusions and Next Steps; GMD Assessment Workflow (TPL-007-1); EMP E3 Coupling to Texas 2000 Bus Model; E3 Coupling Comparison (total GIC) Varying Ground Zero; E3 Coupling Comparison (total MVAR) Varying Ground Zero; E3 Coupling Comparison (GIC) at Peak Ground Zero; E3 Coupling Comparison (GIC) at Peak Ground Zero; and Conclusion.

Disturbance, Functional Diversity and Ecosystem Processes: Does Species Identity Matter?

OpenAIRE

Emrick III, Verl Roy

2013-01-01

The role of disturbance is widely recognized as a fundamental driver of ecological organization from individual species to entire landscapes. Anthropogenic disturbances from military training provide a unique opportunity to examine effects of disturbance on vegetation dynamics, physicochemical soil properties, and ecosystem processes. Additionally, plant functional diversity has been suggested as the key to ecosystem processes such as productivity and nutrient dynamics. I investigated how dis...

Clinical observation of taste disturbance induced by radiation therapy

International Nuclear Information System (INIS)

Murakami, Yuzuru; Sera, Koshi; Nagasawa, Hiroshi; Fukushima, Noriyuki; Yajin, Koji; Harada, Yasuo

1984-01-01

Qualitative gustometry (filter paper disc method) was performed in six patients who underwent radiation therapy. Following results were obtained. 1) Subjective taste disturbance appeared when irradiation dosage amounted to 1000-2000 rad. Whereas, it disappeared in 1 to 3 months after the termination of irradiation. 2) The longer the period of irradiation, the more slowly taste disturbance recovered. 3) Disgeusia was noticed in 44.3% of S, 66.7% of N, 70% of T and 36.2% of Q tests. 4) Taste thresholds in the apical tongue region improved almost parallel to subjective recovery of the taste. Occasionally taste disturbance was prolonged over a month. This is possibly due to delayed regeneration of the gustatory buds. Furthermore, conditions of the oral cavity, such as infection, or mechanical stimulation, may well influence degree of taste disturbance and the process of regeneration. (author)

State-independent error-disturbance trade-off for measurement operators

International Nuclear Information System (INIS)

Zhou, S.S.; Wu, Shengjun; Chau, H.F.

2016-01-01

In general, classical measurement statistics of a quantum measurement is disturbed by performing an additional incompatible quantum measurement beforehand. Using this observation, we introduce a state-independent definition of disturbance by relating it to the distinguishability problem between two classical statistical distributions – one resulting from a single quantum measurement and the other from a succession of two quantum measurements. Interestingly, we find an error-disturbance trade-off relation for any measurements in two-dimensional Hilbert space and for measurements with mutually unbiased bases in any finite-dimensional Hilbert space. This relation shows that error should be reduced to zero in order to minimize the sum of error and disturbance. We conjecture that a similar trade-off relation with a slightly relaxed definition of error can be generalized to any measurements in an arbitrary finite-dimensional Hilbert space.

Composite control for raymond mill based on model predictive control and disturbance observer

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Dan Niu

2016-03-01

Full Text Available In the raymond mill grinding process, precise control of operating load is vital for the high product quality. However, strong external disturbances, such as variations of ore size and ore hardness, usually cause great performance degradation. It is not easy to control the current of raymond mill constant. Several control strategies have been proposed. However, most of them (such as proportional–integral–derivative and model predictive control reject disturbances just through feedback regulation, which may lead to poor control performance in the presence of strong disturbances. For improving disturbance rejection, a control method based on model predictive control and disturbance observer is put forward in this article. The scheme employs disturbance observer as feedforward compensation and model predictive control controller as feedback regulation. The test results illustrate that compared with model predictive control method, the proposed disturbance observer–model predictive control method can obtain significant superiority in disturbance rejection, such as shorter settling time and smaller peak overshoot under strong disturbances.

Disturbance-specific social responses in long-finned pilot whales, Globicephala melas

Science.gov (United States)

Visser, Fleur; Curé, Charlotte; Kvadsheim, Petter H.; Lam, Frans-Peter A.; Tyack, Peter L.; Miller, Patrick J. O.

2016-06-01

Social interactions among animals can influence their response to disturbance. We investigated responses of long-finned pilot whales to killer whale sound playbacks and two anthropogenic sources of disturbance: tagging effort and naval sonar exposure. The acoustic scene and diving behaviour of tagged individuals were recorded along with the social behaviour of their groups. All three disturbance types resulted in larger group sizes, increasing social cohesion during disturbance. However, the nature and magnitude of other responses differed between disturbance types. Tagging effort resulted in a clear increase in synchrony and a tendency to reduce surface logging and to become silent (21% of cases), whereas pilot whales increased surface resting during sonar exposure. Killer whale sounds elicited increased calling rates and the aggregation of multiple groups, which approached the sound source together. This behaviour appears to represent a mobbing response, a likely adaptive social defence against predators or competitors. All observed response-tactics would reduce risk of loss of group coordination, suggesting that, in social pilot whales, this could drive behavioural responses to disturbance. However, the behavioural means used to achieve social coordination depends upon other considerations, which are disturbance-specific.

Most-Critical Transient Disturbances in an Incompressible Flat-Plate Boundary Layer

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Monschke, Jason; White, Edward

2015-11-01

Transient growth is a linear disturbance growth mechanism that plays a key role in roughness-induced boundary-layer transition. It occurs when superposed stable, non-orthogonal continuous spectrum modes experience algebraic disturbance growth followed by exponential decay. Algebraic disturbance growth can modify the basic state making it susceptible to secondary instabilities rapidly leading to transition. Optimal disturbance theory was developed to model the most-dangerous disturbances. However, evidence suggests roughness-induced transient growth is sub-optimal yet leads to transition earlier than optimal theory suggests. This research computes initial disturbances most unstable to secondary instabilities to further develop the applicability of transient growth theory to surface roughness. The main approach is using nonlinear adjoint optimization with solutions of the parabolized Navier-Stokes and BiGlobal stability equations. Two objective functions were considered: disturbance kinetic energy growth and sinuous instability growth rate. The first objective function was used as validation of the optimization method. Counter-rotating streamwise vortices located low in the boundary layer maximize the sinuous instability growth rate. The authors would like to acknowledge NASA and the AFOSR for funding this work through AFOSR Grant FA9550-09-1-0341.

Forest economics, natural disturbances and the new ecology

Science.gov (United States)

Thomas P. Holmes; Robert J. Huggett; John M. Pye

2008-01-01

The major thesis of this chapter is that the economic analysis of forest disturbances will be enhanced by linking economic and ecologic models. Although we only review a limited number of concepts drawn generally from mathematical and empirical ecology, the overarching theme we present is that ecological models of forest disturbance processes are complex and not...

Comparison of methods for determining the hydrologic recovery time after forest disturbance

Science.gov (United States)

Oda, T.; Green, M.; Ohte, N.; Urakawa, R.; Endo, I.; Scanlon, T. M.; Sebestyen, S. D.; McGuire, K. J.; Katsuyama, M.; Fukuzawa, K.; Tague, C.; Hiraoka, M.; Fukushima, K.; Giambelluca, T. W.

2013-12-01

Changes in forest hydrology changes after forest disturbance vary among catchments. Although studies have summarized the initial runoff changes following forest disturbance, the estimates of long-term recovery time are less frequently reported. To understand the mechanisms of long-term recovery processes and to predict the long-term changes in streamflow after forest disturbance, it is important to compare recovery times after disturbance. However, there is no clear consensus regarding the best methodology for such research, especially for watershed studies that were not designed as paired watersheds. We compared methods of determining the hydrologic recovery time to determine if there is a common method for sites in any hydroclimatic setting. We defined the hydrologic recovery time to be the time of disturbance to the time when hydrological factors first recovered to pre-disturbance levels. We acquired data on long-term rainfall and runoff at 16 sites in northeastern USA and Japan that had at least 10 years (and up to 50 years) of post disturbance data. The types of disturbance include harvesting, diseases and insect damages. We compared multiple indices of hydrological response including annual runoff, annual runoff ratio (annual runoff/annual rainfall), annual loss (annual rainfall-annual runoff), fiftieth-percentile annual flow, and seasonal water balance. The results showed that comparing annual runoff to a reference site was most robust at constraining the recovery time, followed by using pre-disturbance data as reference data and calculating the differences in annual runoff from pre-disturbance levels. However, in case of small disturbance at sites without reference data or long-term pre-disturbance data, the inter-annual variation of rainfall makes the effect of disturbance unclear. We found that annual loss had smaller inter-annual variation, and defining recovery time with annual loss was best in terms of matching the results from paired watersheds. The

Parallel neural pathways in higher visual centers of the Drosophila brain that mediate wavelength-specific behavior

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Hideo eOtsuna

2014-02-01

Full Text Available Compared with connections between the retinae and primary visual centers, relatively less is known in both mammals and insects about the functional segregation of neural pathways connecting primary and higher centers of the visual processing cascade. Here, using the Drosophila visual system as a model, we demonstrate two levels of parallel computation in the pathways that connect primary visual centers of the optic lobe to computational circuits embedded within deeper centers in the central brain. We show that a seemingly simple achromatic behavior, namely phototaxis, is under the control of several independent pathways, each of which is responsible for navigation towards unique wavelengths. Silencing just one pathway is enough to disturb phototaxis towards one characteristic monochromatic source, whereas phototactic behavior towards white light is not affected. The response spectrum of each demonstrable pathway is different from that of individual photoreceptors, suggesting subtractive computations. A choice assay between two colors showed that these pathways are responsible for navigation towards, but not for the detection itself of, the monochromatic light. The present study provides novel insights about how visual information is separated and processed in parallel to achieve robust control of an innate behavior.

Climate change amplifies the interactions between wind and bark beetle disturbances in forest landscapes.

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Seidl, Rupert; Rammer, Werner

2017-07-01

Growing evidence suggests that climate change could substantially alter forest disturbances. Interactions between individual disturbance agents are a major component of disturbance regimes, yet how interactions contribute to their climate sensitivity remains largely unknown. Here, our aim was to assess the climate sensitivity of disturbance interactions, focusing on wind and bark beetle disturbances. We developed a process-based model of bark beetle disturbance, integrated into the dynamic forest landscape model iLand (already including a detailed model of wind disturbance). We evaluated the integrated model against observations from three wind events and a subsequent bark beetle outbreak, affecting 530.2 ha (3.8 %) of a mountain forest landscape in Austria between 2007 and 2014. Subsequently, we conducted a factorial experiment determining the effect of changes in climate variables on the area disturbed by wind and bark beetles separately and in combination. iLand was well able to reproduce observations with regard to area, temporal sequence, and spatial pattern of disturbance. The observed disturbance dynamics was strongly driven by interactions, with 64.3 % of the area disturbed attributed to interaction effects. A +4 °C warming increased the disturbed area by +264.7 % and the area-weighted mean patch size by +1794.3 %. Interactions were found to have a ten times higher sensitivity to temperature changes than main effects, considerably amplifying the climate sensitivity of the disturbance regime. Disturbance interactions are a key component of the forest disturbance regime. Neglecting interaction effects can lead to a substantial underestimation of the climate change sensitivity of disturbance regimes.

Long-term visual damage after acute methanol poisonings: Longitudinal cross-sectional study in 50 patients.

Science.gov (United States)

Zakharov, Sergey; Pelclova, Daniela; Diblik, Pavel; Urban, Pavel; Kuthan, Pavel; Nurieva, Olga; Kotikova, Katerina; Navratil, Tomas; Komarc, Martin; Belacek, Jaromir; Seidl, Zdenek; Vaneckova, Manuela; Hubacek, Jaroslav A; Bezdicek, Ondrej; Klempir, Jiri; Yurchenko, Maksim; Ruzicka, Evzen; Miovsky, Michal; Janikova, Barbara; Hovda, Knut Erik

2015-11-01

Visual disturbances due to the toxic effect of formic acid in acute methanol poisonings are generally transient. The subjective symptoms of visual toxicity may resolve within few weeks and fundoscopic signs of acute optic neuropathy subside within 1-2 months; therefore, the prevalence of long-term visual sequelae in the population of survivors of poisonings may be underestimated. To study the prevalence and character of long-term visual sequelae of acute methanol poisonings based on the data from the Czech mass methanol outbreak in 2012. A total of 50 patients with confirmed methanol poisoning were included in this longitudinal cross-sectional study, median age: 48 (range, 23-73) years. The following tests were performed: optical coherence tomography or OCT with evaluation of the retinal nerve fibers layer (RNFL), visual evoked potentials (VEP), magnetic resonance imaging (MRI) of brain, complete ocular examination (visual acuity/field, color vision, contrast sensitivity, and fundus), neurological examinations, and biochemical tests. Of 50 patients, 7/50 (14%) were discharged with diagnosed visual sequelae and 6/50 (12%) were discharged with both visual and central nervous system sequelae of poisoning. On the follow-up examination, 20/50 (40%) of the patients had long-term visual sequelae, with 8% of blindness. A total of 38% of the patients had abnormal (28% borderline) findings on RNFL, and 40% had abnormal (18% borderline) VEP. Among the patients discharged without detected visual sequelae, 8/37 (22%) had abnormal RNFL and VEP. Patients with visual sequelae had brain lesions more often (70% vs. 27%, p methanol, ethanol, HCO3-, formate, pH, anion gap, and base deficit (all p methanol poisonings in general.

Disturbances in small bowel motility.

LENUS (Irish Health Repository)

Quigley, E M

2012-02-03

Recently, the small intestine has become the focus of investigation as a potential site of dysmotility in the irritable bowel syndrome (IBS). A number of motor abnormalities have been defined in some studies, and include \\'clustered\\' contractions, exaggerated post-prandial motor response and disturbances in intestinal transit. The significance of these findings remains unclear. The interpretation of available studies is complicated by differences in subject selection, the direct influence of certain symptoms, such as diarrhoea and constipation, and the interference of compounding factors, such as stress and psychopathology. Dysmotility could also reflect autonomic dysfunction, disturbed CNS control and the response to heightened visceral sensation or central perception. While motor abnormalities may not explain all symptoms in IBS, sensorimotor interactions may be important in symptom pathogenesis and deserve further study.

Pathophysiology of visual disorders induced by phosphodiesterase inhibitors in the treatment of erectile dysfunction

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Moschos MM

2016-10-01

Full Text Available Marilita M Moschos, Eirini Nitoda 1st Department of Ophthalmology, Medical School, National & Kapodistrian University of Athens, Athens, Greece Aim: The aim of this review was to summarize the ocular action of the most common phosphodiesterase (PDE inhibitors used for the treatment of erectile dysfunction and the subsequent visual disorders.Method: This is a literature review of several important articles focusing on the pathophysiology of visual disorders induced by PDE inhibitors.Results: PDE inhibitors have been associated with ocular side effects, including changes in color vision and light perception, blurred vision, transient alterations in electroretinogram (ERG, conjunctival hyperemia, ocular pain, and photophobia. Sildenafil and tadalafil may induce reversible increase in intraocular pressure and be involved in the development of nonarteritic ischemic optic neuropathy. Reversible idiopathic serous macular detachment, central serous chorioretinopathy, and ERG disturbances have been related to the significant impact of sildenafil and tadalafil on retinal perfusion.Discussion: So far, PDE inhibitors do not seem to cause permanent toxic effects on chorioretinal tissue and photoreceptors. However, physicians should write down any visual symptom observed during PDE treatment and refer the patients to ophthalmologists. Keywords: erectile dysfunction, pathophysiological mechanisms, phosphodiesterase inhibitors, PDE5, visual disorders

Chronic stress, catecholamines, and sleep disturbance at Three Mile Island

International Nuclear Information System (INIS)

Davidson, L.M.; Fleming, R.; Baum, A.

1987-01-01

The present study was concerned with the relationship between chronic stress and sleep disturbance. Previous research has provided evidence of chronic stress responding among people living near the Three Mile Island nuclear generating facility. Compared to control subjects, the TMI group has exhibited greater symptom reporting, poorer performance on behavioral measures of concentration, and elevated levels of urinary norepinephrine and epinephrine. Other research has suggested a relationship between arousal and insomnia. The extent to which stress and sleep disturbances were experienced by residents at TMI was examined and compared to levels of stress and sleep disturbance among a group of control subjects. The relationship between stress and sleep disturbances was also examined. Results indicated that TMI area residents exhibited more stress than the controls and reported greater disturbance of sleep. Modest relationships among stress and sleep measures suggested that the symptoms of stress measured in this study were not primary determinants of sleep problems

Chronic stress, catecholamines, and sleep disturbance at Three Mile Island.

Science.gov (United States)

Davidson, L M; Fleming, R; Baum, A

1987-01-01

The present study was concerned with the relationship between chronic stress and sleep disturbance. Previous research has provided evidence of chronic stress responding among people living near the Three Mile Island nuclear generating facility. Compared to control subjects, the TMI group has exhibited greater symptom reporting, poorer performance on behavioral measures of concentration, and elevated levels of urinary norepinephrine and epinephrine. Other research has suggested a relationship between arousal and insomnia. The extent to which stress and sleep disturbances were experienced by residents at TMI was examined and compared to levels of stress and sleep disturbance among a group of control subjects. The relationship between stress and sleep disturbances was also examined. Results indicated that TMI area residents exhibited more stress than the controls and reported greater disturbance of sleep. Modest relationships among stress and sleep measures suggested that the symptoms of stress measured in this study were not primary determinants of sleep problems.

Social Integration and Sleep Disturbance: A Gene-Environment Interaction Study

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David A. Sbarra

2016-03-01

Full Text Available Objective: Low levels of perceived social integration, or loneliness, are associated with increased risk for a range of poor health outcomes. Sleep disturbance plays a central role in the evolutionary theory of loneliness, which provides a mechanistic account of how low levels of social integration may negatively impact health. No studies, however, have examined whether the association between social integration and sleep disturbance is consistent with a causal effect after accounting for genes that are common to both variables.  Method: Using twin data ('N' = 905 twin pairs from the nationally-representative Midlife in the United States (MIDUS survey, I evaluated a series of bivariate twin models exploring whether the phenotypic association between low social integration and sleep disturbance can be explained by shared genetics. In addition, the current study specified a series of quantitative models for studying gene x environment (G X E interactions to determine whether the genetic and environmental influences on sleep disturbance differ as a function of social integration. Results: The phenotypic association between social integration and sleep disturbance was fully accounted for by genes that are common between the two variables, suggesting that within-twin pair differences in social integration do not exert a causal influence on sleep disturbance. Social integration, however, moderated the non-shared environmental influence on sleep disturbances, with the greatest environmental influences observed at the lowest levels of social integration. Conclusions: The results of this study suggest that an essential feature of the evolutionary model of loneliness may need refinement or elaboration. The moderation findings are discussed in terms of the fit with a stress-buffering model of social support in which environmental influences on sleep disturbance are strongest when social resources are low.

Human-caused Disturbance Stimuli as a Form of Predation Risk

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Alejandro Frid

2002-06-01

Full Text Available A growing number of studies quantify the impact of nonlethal human disturbance on the behavior and reproductive success of animals. Athough many are well designed and analytically sophisticated, most lack a theoretical framework for making predictions and for understanding why particular responses occur. Behavioral ecologists have recently begun to fill this theoretical vacuum by applying economic models of antipredator behavior to disturbance studies. In this emerging paradigm, predation and nonlethal disturbance stimuli create similar trade-offs between avoiding perceived risk and other fitness-enhancing activities, such as feeding, parental care, or mating. A vast literature supports the hypothesis that antipredator behavior has a cost to other activities, and that this trade-off is optimized when investment in antipredator behavior tracks short-term changes in predation risk. Prey have evolved antipredator responses to generalized threatening stimuli, such as loud noises and rapidly approaching objects. Thus, when encountering disturbance stimuli ranging from the dramatic, low-flying helicopter to the quiet wildlife photographer, animal responses are likely to follow the same economic principles used by prey encountering predators. Some authors have argued that, similar to predation risk, disturbance stimuli can indirectly affect fitness and population dynamics via the energetic and lost opportunity costs of risk avoidance. We elaborate on this argument by discussing why, from an evolutionary perspective, disturbance stimuli should be analogous to predation risk. We then consider disturbance effects on the behavior of individuals - vigilance, fleeing, habitat selection, mating displays, and parental investment - as well as indirect effects on populations and communities. A wider application of predation risk theory to disturbance studies should increase the generality of predictions and make mitigation more effective without over

An Optimization-Based System Model of Disturbance-Generated Forest Biomass Utilization

Science.gov (United States)

Curry, Guy L.; Coulson, Robert N.; Gan, Jianbang; Tchakerian, Maria D.; Smith, C. Tattersall

2008-01-01

Disturbance-generated biomass results from endogenous and exogenous natural and cultural disturbances that affect the health and productivity of forest ecosystems. These disturbances can create large quantities of plant biomass on predictable cycles. A systems analysis model has been developed to quantify aspects of system capacities (harvest,…

Impaired Prefrontal-Amygdala Pathway, Self-Reported Emotion, and Erection in Psychogenic Erectile Dysfunction Patients With Normal Nocturnal Erection

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Jianhuai Chen

2018-04-01

Full Text Available Background: Neuroimaging studies have demonstrated that the prefrontal cortex and amygdala play an important role in sexual arousal (SA. However, little is known about the interactions between the prefrontal and cortex amygdala, which mediate the cognitive regulation of emotion and SA.Objective: We seek to determine whether nocturnal erection of psychogenic erectile dysfunction (pED patients are normal and whether there are changes of topological organization in the prefrontal-amygdala pathway of brain network in pED. In addition, whether there are correlations between network property changes and self-reported emotion and erection.Design, setting, and participants: We used the RigiScan device to evaluate erectile function of patients and employed diffusion MRI and graph theory to construct brain networks of 21 pED patients and 24 healthy controls.Outcome measurements and statistical analysis: We considered four nodal metrics and their asymmetry scores, and nocturnal penile tumescence (NPT parameters, to evaluate the topological properties of brain networks of pED and their relationships with the impaired self-reported emotion and erection.Results and limitations: All the pED patients showed normal nocturnal penile erection, however impaired self-reported erection and negative emotion. In addition, patients showed lower connectivity degree and strength in the left prefrontal-amygdala pathway. We also found that pED exhibited lower leftward asymmetry in the inferior frontal gyrus. Furthermore, patients showed more hub regions and fewer pivotal connections. Moreover, the degree of the left amygdala of pED showed significantly negative correlation with the self-reported erection and positive correlation with the self-reported negative emotion.Conclusions: Together, these results suggest normal nocturnal erection in pED. However, abnormalities of brain network organization in pED, particularly in the left prefrontal-amygdala pathway, are associated

Impaired Prefrontal-Amygdala Pathway, Self-Reported Emotion, and Erection in Psychogenic Erectile Dysfunction Patients With Normal Nocturnal Erection

Science.gov (United States)

Chen, Jianhuai; Chen, Yun; Gao, Qingqiang; Chen, Guotao; Dai, Yutian; Yao, Zhijian; Lu, Qing

2018-01-01

Background: Neuroimaging studies have demonstrated that the prefrontal cortex and amygdala play an important role in sexual arousal (SA). However, little is known about the interactions between the prefrontal and cortex amygdala, which mediate the cognitive regulation of emotion and SA. Objective: We seek to determine whether nocturnal erection of psychogenic erectile dysfunction (pED) patients are normal and whether there are changes of topological organization in the prefrontal-amygdala pathway of brain network in pED. In addition, whether there are correlations between network property changes and self-reported emotion and erection. Design, setting, and participants: We used the RigiScan device to evaluate erectile function of patients and employed diffusion MRI and graph theory to construct brain networks of 21 pED patients and 24 healthy controls. Outcome measurements and statistical analysis: We considered four nodal metrics and their asymmetry scores, and nocturnal penile tumescence (NPT) parameters, to evaluate the topological properties of brain networks of pED and their relationships with the impaired self-reported emotion and erection. Results and limitations: All the pED patients showed normal nocturnal penile erection, however impaired self-reported erection and negative emotion. In addition, patients showed lower connectivity degree and strength in the left prefrontal-amygdala pathway. We also found that pED exhibited lower leftward asymmetry in the inferior frontal gyrus. Furthermore, patients showed more hub regions and fewer pivotal connections. Moreover, the degree of the left amygdala of pED showed significantly negative correlation with the self-reported erection and positive correlation with the self-reported negative emotion. Conclusions: Together, these results suggest normal nocturnal erection in pED. However, abnormalities of brain network organization in pED, particularly in the left prefrontal-amygdala pathway, are associated with the

Intensive ground vegetation growth mitigates the carbon loss after forest disturbance.

Science.gov (United States)

Zehetgruber, Bernhard; Kobler, Johannes; Dirnböck, Thomas; Jandl, Robert; Seidl, Rupert; Schindlbacher, Andreas

2017-01-01

Slow or failed tree regeneration after forest disturbance is increasingly observed in the central European Alps, potentially amplifying the carbon (C) loss from disturbance. We aimed at quantifying C dynamics of a poorly regenerating disturbance site with a special focus on the role of non-woody ground vegetation. Soil CO 2 efflux, fine root biomass, ground vegetation biomass, tree increment and litter input were assessed in (i) an undisturbed section of a ~ 110 years old Norway spruce stand, (ii) in a disturbed section which was clear-cut six years ago (no tree regeneration), and (iii) in a disturbed section which was clear-cut three years ago (no tree regeneration). Total soil CO 2 efflux was similar across all stand sections (8.5 ± 0.2 to 8.9 ± 0.3 t C ha -1  yr. -1 ). The undisturbed forest served as atmospheric C sink (2.1 t C ha -1  yr. -1 ), whereas both clearings were C sources to the atmosphere. The source strength three years after disturbance (-5.5 t C ha -1  yr. -1 ) was almost twice as high as six years after disturbance (-2.9 t C ha -1  yr. -1 ), with declining heterotrophic soil respiration and the high productivity of dense graminoid ground vegetation mitigating C loss. C loss after disturbance decreases with time and ground vegetation growth. Dense non-woody ground vegetation cover can hamper tree regeneration but simultaneously decrease the ecosystem C loss. The role of ground vegetation should be more explicitly taken into account in forest C budgets assessing disturbance effects.

Tree species diversity mitigates disturbance impacts on the forest carbon cycle.

Science.gov (United States)

Silva Pedro, Mariana; Rammer, Werner; Seidl, Rupert

2015-03-01

Biodiversity fosters the functioning and stability of forest ecosystems and, consequently, the provision of crucial ecosystem services that support human well-being and quality of life. In particular, it has been suggested that tree species diversity buffers ecosystems against the impacts of disturbances, a relationship known as the "insurance hypothesis". Natural disturbances have increased across Europe in recent decades and climate change is expected to amplify the frequency and severity of disturbance events. In this context, mitigating disturbance impacts and increasing the resilience of forest ecosystems is of growing importance. We have tested how tree species diversity modulates the impact of disturbance on net primary production and the total carbon stored in living biomass for a temperate forest landscape in Central Europe. Using the simulation model iLand to study the effect of different disturbance regimes on landscapes with varying levels of tree species richness, we found that increasing diversity generally reduces the disturbance impact on carbon storage and uptake, but that this effect weakens or even reverses with successional development. Our simulations indicate a clear positive relationship between diversity and resilience, with more diverse systems experiencing lower disturbance-induced variability in their trajectories of ecosystem functioning. We found that positive effects of tree species diversity are mainly driven by an increase in functional diversity and a modulation of traits related to recolonization and resource usage. The results of our study suggest that increasing tree species diversity could mitigate the effects of intensifying disturbance regimes on ecosystem functioning and improve the robustness of forest carbon storage and the role of forests in climate change mitigation.

[A novel proposal explaining sleep disturbance of children in Japan--asynchronization].

Science.gov (United States)

Kohyama, Jun

2008-07-01

It has been reported that more than half of the children in Japan suffer from daytime sleepiness. In contrast, about one quarter of junior high-school students in Japan complain of insomnia. According to the International Classification of Sleep Disorders (Second edition), these children could be diagnosed as having behaviorally-induced insufficient sleep syndrome due to inadequate sleeping habits. Getting on adequate amount of sleep should solve such problems;however, such a therapeutic approach often fails. Although social factors are involved in these sleep disturbances, I feel that a novel notion - asynchronization - leads to an understanding of the pathophysiology of disturbances in these children. Further, it could contribute to resolve their problems. The essence of asynchronization is a disturbance of various aspects (e.g., cycle, amplitude, phase, and interrelationship) of the biological rhythms that normally exhibits circadian oscillation. The main cause of asynchronization is hypothesized to be the combination of light exposure during night and the lack of light exposure in the morning. Asynchronization results in the disturbance of variable systems. Thus, symptoms of asynchronization include disturbances of the autonomic nervous system (sleepiness, insomnia, disturbance of hormonal excretion, gastrointestinal problems, etc.) and higher brain function (disorientation, loss of sociality, loss of will or motivation, impaired alertness and performance, etc.). Neurological (attention deficit, aggression, impulsiveness, hyperactivity, etc.), psychiatric (depressive disorders, personality disorders, anxiety disorders, etc.) and somatic (tiredness, fatigue, etc.) disturbances could also be symptoms of asynchronization. At the initial phase of asynchronization, disturbances are functional and can be resolved relatively easily, such as by the establishment of a regular sleep-wakefulness cycle;however, without adequate intervention the disturbances could gradually

Diurnal patterns and relationships between physiological and self-reported stress in patients with epilepsy and psychogenic non-epileptic seizures.

Science.gov (United States)

Novakova, Barbora; Harris, Peter R; Reuber, Markus

2017-05-01

Patients with epilepsy and those with psychogenic non-epileptic seizures (PNES) experience high levels of stress and stress is one of the most frequently self-identified seizure precipitants. Although stress is a multifaceted phenomenon, few studies have systematically examined its different components in patients with seizures. The aim of this study was therefore to describe diurnal patterns of psychological and physiological measures of stress in patients with epilepsy and patients with PNES, and explore their relationships to each other in order to improve our understanding of the mechanisms underlying stress and seizure occurrence in these patients. A range of stress markers including self-reported stress, salivary cortisol, and heart rate variability (HRV) were explored in adult patients with refractory epilepsy (N=22) and those with PNES (N=23) undergoing three- to five-day video-telemetry. A diurnal pattern was observed in the physiological measures, characterized by higher levels of physiological arousal in the mornings and lower levels at night in both patients with epilepsy and PNES. The physiological measures (cortisol and HRV) were associated with each other in patients with epilepsy; no close relationship was found with self-reported stress in either of the two patient groups. The findings contribute to and expand on previous studies of the patterns of stress in patients with seizures. The results also indicate a discrepancy between patients' physiological responses and their subjective stress perceptions, suggesting that simple self-reports cannot be used as a proxy of physiological arousal in patients with seizures and stress. Stress in these patient groups should be studied using a combination of complementary measures. Copyright © 2017 Elsevier Inc. All rights reserved.

Nutritional disturbances by adolescent

OpenAIRE

Stassart, Martine

2011-01-01

The nutritional disturbances are frequent by adolescents. That is a psychological defense against dependance toward the mother but also a middle to remain in a childish position i.e. either as a fat baby - in the fall of obesity- or as the ideal pre- or bisexual great child - in the case of anorexia.

Robust finite-time tracking control for nonlinear suspension systems via disturbance compensation

Science.gov (United States)

Pan, Huihui; Jing, Xingjian; Sun, Weichao

2017-05-01

This paper focuses on the finite-time tracking control with external disturbance for active suspension systems. In order to compensate unknown disturbance efficiently, a disturbance compensator with finite-time convergence property is studied. By analyzing the discontinuous phenomenon of classical disturbance compensation techniques, this study presents a simple approach to construct a continuous compensator satisfying the finite-time disturbance rejection performance. According to the finite-time separation principle, the design procedures of the nominal controller for the suspension system without disturbance and the disturbance compensator can be implemented in a completely independent manner. Therefore, the overall control law for the closed-loop system is continuous, which offers some distinct advantages over the existing discontinuous ones. From the perspective of practical implementation, the continuous controller can avoid effectively the unexpected chattering in active suspension control. Comparative experimental results are presented and discussed to illustrate the advantage and effectiveness of the proposed control strategy.

Sleep Disturbance Following Concussion Is a Risk Factor for a Prolonged Recovery.

Science.gov (United States)

Bramley, Harry; Henson, Alyssa; Lewis, Mechelle M; Kong, Lan; Stetter, Christy; Silvis, Matthew

2017-12-01

Sleep disturbance is a common problem following concussion. A retrospective chart review was conducted at a regional concussion clinic on patients 13 to 18 years of age between 2005 and 2011. Statistical analysis evaluated sleep disturbance and duration of concussion, as well as the use and effectiveness of melatonin. A total of 417 patients met inclusion criteria. One hundred twenty-three (34%) reported disturbance in sleep. There was no difference in sleep disturbance based on age, gender, or past number of concussions. Sleep disturbance was associated with a 3- to 4-fold increase in recovery time. Non-sport-related concussions were more likely to be associated with sleep disturbance compared to sport-related concussions (45% vs 29%, P = .01). Melatonin improved sleep disturbance in 67% of the patients. Evaluating sleep disorders following concussion is an important part of the assessment. These findings will help clinicians provide anticipatory guidance and treatment for adolescents recovering from concussion.

Model reduction of nonlinear systems subject to input disturbances

KAUST Repository

Ndoye, Ibrahima; Laleg-Kirati, Taous-Meriem

2017-01-01

The method of convex optimization is used as a tool for model reduction of a class of nonlinear systems in the presence of disturbances. It is shown that under some conditions the nonlinear disturbed system can be approximated by a reduced order

Visual findings as primary manifestations in patients with intracranial tumors

Directory of Open Access Journals (Sweden)

Nazife Sefi-Yurdakul

2015-08-01

Full Text Available AIM:To evaluate the visual findings as primary manifestations in patients with intracranial tumors.METHODS:The medical charts of the patients with intracranial tumors who initially admitted to the Neuro-ophthalmology and Strabismus Department with ocular complaints between August 1999 and December 2012 were reviewed retrospectively. The detailed clinical history and the findings of neuro-ophthalmologic examination were recorded. Ocular symptoms and signs, the types and locations of intracranial tumors, and the duration of symptoms before the diagnosis were evaluated.RESULTS:The mean age of 11 women (61.1% and 7 men (38.9% was 42.2±11.0 (range 20-66y at the time of intracranial tumor diagnosis. Initial symptoms were transient visual obscurations, visual loss or visual field defect in 16 cases (88.9%, and diplopia in 2 cases (11.1%. Neuro-ophthalmologic examination revealed normal optic discs in both eyes of 6 patients (33.3%, paleness, atrophy or edema of optic disc in 12 patients (66.7%, and sixth cranial nerve palsy in 2 patients (11.1%. Visual acuity ranged between normal vision and loss of light perception. Cranial imaging demonstrated craniopharyngioma (n=1, plasmacytoma (n=1, meningioma (n=6; olfactory groove and tuberculum sellae, pontocerebellar angle, anterior cranial fossa, frontal vertex, suprasellar region, and pituitary macroadenoma (n=10. The mean duration between the onset of visual disturbances and the diagnosis of intracranial tumor was 9.8±18mo (range 3d-6y.CONCLUSION:The ophthalmologist is frequently the first physician to encounter a patient with clinical manifestations of intracranial tumors that may cause neurological and ocular complications. Neuro-ophthalmologic findings should be carefully evaluated to avoid a delay in the diagnosis of intracranial tumors.

Visual findings as primary manifestations in patients with intracranial tumors

Institute of Scientific and Technical Information of China (English)

Nazife; Sefi-Yurdakul

2015-01-01

· AIM: To evaluate the visual findings as primary manifestations in patients with intracranial tumors.·METHODS: The medical charts of the patients with intracranial tumors who initially admitted to the Neuro-ophthalmology and Strabismus Department with ocular complaints between August 1999 and December 2012 were reviewed retrospectively. The detailed clinical history and the findings of neuro-ophthalmologic examination were recorded. Ocular symptoms and signs,the types and locations of intracranial tumors, and the duration of symptoms before the diagnosis were evaluated.·RESULTS: The mean age of 11 women(61.1%) and 7men(38.9%) was 42.2±11.0(range 20-66y) at the time of intracranial tumor diagnosis. Initial symptoms were transient visual obscurations, visual loss or visual field defect in 16 cases(88.9%), and diplopia in 2 cases(11.1%). Neuro-ophthalmologic examination revealed normal optic discs in both eyes of 6 patients(33.3%),paleness, atrophy or edema of optic disc in 12 patients(66.7%), and sixth cranial nerve palsy in 2 patients(11.1%). Visual acuity ranged between normal vision and loss of light perception. Cranial imaging demonstrated craniopharyngioma(n =1), plasmacytoma(n =1),meningioma(n =6; olfactory groove and tuberculum sellae, pontocerebellar angle, anterior cranial fossa,frontal vertex, suprasellar region), and pituitary macroadenoma(n =10). The mean duration between the onset of visual disturbances and the diagnosis of intracranial tumor was 9.8±18mo(range 3d-6y).·CONCLUSION: The ophthalmologist is frequently the first physician to encounter a patient with clinical manifestations of intracranial tumors that may cause neurological and ocular complications. Neuro-ophthalmologic findings should be carefully evaluated to avoid a delay in the diagnosis of intracranial tumors.

Body image disturbance in adults treated for cancer - a concept analysis.

Science.gov (United States)

Rhoten, Bethany A

2016-05-01

To report an analysis of the concept of body image disturbance in adults who have been treated for cancer as a phenomenon of interest to nurses. Although the concept of body image disturbance has been clearly defined in adolescents and adults with eating disorders, adults who have been treated for cancer may also experience body image disturbance. In this context, the concept of body image disturbance has not been clearly defined. Concept analysis. PubMed, Psychological Information Database and Cumulative Index of Nursing and Allied Health Literature were searched for publications from 1937 - 2015. Search terms included body image, cancer, body image disturbance, adult and concept analysis. Walker and Avant's 8-step method of concept analysis was used. The defining attributes of body image disturbance in adults who have been treated for cancer are: (1) self-perception of a change in appearance and displeasure with the change or perceived change in appearance; (2) decline in an area of function; and (3) psychological distress regarding changes in appearance and/or function. This concept analysis provides a foundation for the development of multidimensional assessment tools and interventions to alleviate body image disturbance in this population. A better understanding of body image disturbance in adults treated for cancer will assist nurses and other clinicians in identifying this phenomenon and nurse scientists in developing instruments that accurately measure this condition, along with interventions that will promote a better quality of life for survivors. © 2016 John Wiley & Sons Ltd.

Nutrient Release from Disturbance of Infiltration System Soils during Construction

Directory of Open Access Journals (Sweden)

Daniel P. Treese

2012-01-01

Full Text Available Subsurface infiltration and surface bioretention systems composed of engineered and/or native soils are preferred tools for stormwater management. However, the disturbance of native soils, especially during the process of adding amendments to improve infiltration rates and pollutant removal, may result in releases of nutrients in the early life of these systems. This project investigated the nutrient release from two soils, one disturbed and one undisturbed. The disturbed soil was collected intact, but had to be air-dried, and the columns repacked when soil shrinkage caused bypassing of water along the walls of the column. The undisturbed soil was collected and used intact, with no repacking. The disturbed soil showed elevated releases of nitrogen and phosphorus compared to the undisturbed soil for approximately 0.4 and 0.8 m of runoff loading, respectively. For the undisturbed soil, the nitrogen release was delayed, indicating that the soil disturbance accelerated the release of nitrogen into a very short time period. Leaving the soil undisturbed resulted in lower but still elevated effluent nitrogen concentrations over a longer period of time. For phosphorus, these results confirm prior research which demonstrated that the soil, if shown to be phosphorus-deficient during fertility testing, can remove phosphorus from runoff even when disturbed.

The role of forest disturbance in global forest mortality and terrestrial carbon fluxes

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Pugh, Thomas; Arneth, Almut; Smith, Benjamin; Poulter, Benjamin

2017-04-01

Large-scale forest disturbance dynamics such as insect outbreaks, wind-throw and fires, along with anthropogenic disturbances such as logging, have been shown to turn forests from carbon sinks into intermittent sources, often quite dramatically so. There is also increasing evidence that disturbance regimes in many regions are changing as a result of climatic change and human land-management practices. But how these landscape-scale events fit into the wider picture of global tree mortality is not well understood. Do such events dominate global carbon turnover, or are their effects highly regional? How sensitive is global terrestrial carbon exchange to realistic changes in the occurrence rate of such disturbances? Here, we combine recent advances in global satellite observations of stand-replacing forest disturbances and in compilations of forest inventory data, with a global terrestrial ecosystem model which incorporates an explicit representation of the role of disturbance in forest dynamics. We find that stand-replacing disturbances account for a fraction of wood carbon turnover that varies spatially from less than 5% in the tropical rainforest to ca. 50% in the mid latitudes, and as much as 90% in some heavily-managed regions. We contrast the size of the land-atmosphere carbon flux due to this disturbance with other components of the terrestrial carbon budget. In terms of sensitivity, we find a quasi log-linear relationship of disturbance rate to total carbon storage. Relatively small changes in disturbance rates at all latitudes have marked effects on vegetation carbon storage, with potentially very substantial implications for the global terrestrial carbon sink. Our results suggest a surprisingly small effect of disturbance type on large-scale forest vegetation dynamics and carbon storage, with limited evidence of widespread increases in nitrogen limitation as a result of increasing future disturbance. However, the influence of disturbance type on soil carbon

Stress and sleep disturbances in female college students.

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Lee, Shih-Yu; Wuertz, Caroline; Rogers, Rebecca; Chen, Yu-Ping

2013-11-01

To describe the sleep characteristics and examine the associations among perceived stress, sleep disturbances, depressive symptoms, and physical symptoms among female college students. A total of 103 students completed a battery of questionnaires. The students experienced high stress during the school year. The majority of them slept less than 6 hours during weekdays and experienced moderate fatigue. High stress levels are associated with sleep disturbances, less nocturnal total sleep time, higher fatigue severity, and more depressive symptoms. Perceived stress and sleep disturbances are significant predictors for depressive symptoms and physical symptoms. Compared to the good sleepers, the poor sleepers reported more daytime sleepiness, depressive symptoms, and physical symptoms. Interventions to reduce stress and improve sleep are critically needed in college education.

Robust lane detection and tracking using multiple visual cues under stochastic lane shape conditions

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Huang, Zhi; Fan, Baozheng; Song, Xiaolin

2018-03-01

As one of the essential components of environment perception techniques for an intelligent vehicle, lane detection is confronted with challenges including robustness against the complicated disturbance and illumination, also adaptability to stochastic lane shapes. To overcome these issues, we proposed a robust lane detection method named classification-generation-growth-based (CGG) operator to the detected lines, whereby the linear lane markings are identified by synergizing multiple visual cues with the a priori knowledge and spatial-temporal information. According to the quality of linear lane fitting, the linear and linear-parabolic models are dynamically switched to describe the actual lane. The Kalman filter with adaptive noise covariance and the region of interests (ROI) tracking are applied to improve the robustness and efficiency. Experiments were conducted with images covering various challenging scenarios. The experimental results evaluate the effectiveness of the presented method for complicated disturbances, illumination, and stochastic lane shapes.

Form of the compensatory stepping response to repeated laterally directed postural disturbances.

Science.gov (United States)

Hurt, Christopher P; Rosenblatt, Noah J; Grabiner, Mark D

2011-10-01

A compensatory stepping response (CSR) is a common strategy to restore dynamic stability in response to a postural disturbance. Currently, few studies have investigated the CSR to laterally directed disturbances delivered to subjects during quiet standing. The purpose of this study was to characterize the CSR of younger adults following exposure to a series of similar laterally directed disturbances for which no instructions were given with regard to the recovery response. We hypothesized that in the absence of externally applied constraints to the recovery response, subjects would be equally as likely to perform a crossover step as a sidestep sequence (SSS). We further hypothesized that there would be an asymmetry in arm abduction that would be dependent on the disturbance direction. Finally, we were interested in characterizing the effect of practice on the CSR to repeated disturbances. Ten younger adults were exposed to thirty laterally directed platform disturbances that forced a stepping response. Subjects responded by primarily utilizing a SSS that differs from previously reported results. Further, five of the ten subjects utilized a different recovery response that was dependent on the direction of the disturbance (i.e., left or right). Greater arm abduction was characterized for the arm in the direction of the external disturbance in comparison with the contralateral arm. Lastly, subjects modified their recovery response to this task within 12 disturbances. Taken together, these results suggest that recovery responses to laterally directed disturbances can be quickly modified but can be quite variable between and within subjects.

Learning Visualizations by Analogy: Promoting Visual Literacy through Visualization Morphing.

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Ruchikachorn, Puripant; Mueller, Klaus

2015-09-01

We propose the concept of teaching (and learning) unfamiliar visualizations by analogy, that is, demonstrating an unfamiliar visualization method by linking it to another more familiar one, where the in-betweens are designed to bridge the gap of these two visualizations and explain the difference in a gradual manner. As opposed to a textual description, our morphing explains an unfamiliar visualization through purely visual means. We demonstrate our idea by ways of four visualization pair examples: data table and parallel coordinates, scatterplot matrix and hyperbox, linear chart and spiral chart, and hierarchical pie chart and treemap. The analogy is commutative i.e. any member of the pair can be the unfamiliar visualization. A series of studies showed that this new paradigm can be an effective teaching tool. The participants could understand the unfamiliar visualization methods in all of the four pairs either fully or at least significantly better after they observed or interacted with the transitions from the familiar counterpart. The four examples suggest how helpful visualization pairings be identified and they will hopefully inspire other visualization morphings and associated transition strategies to be identified.