Relations between neuropsychological findings and lateral asymmetries of cerebral blood flow measured by SPECT in dementia of Alzheimer type

International Nuclear Information System (INIS)

Yoshimura, Nahoko; Soma, Yoshiaki; Ootsuki, Mika

1993-01-01

We studied 16 right-handed patients clinically diagnosed as dementia of Alzheimer type (6 men, 10 women; aged 63-85, mean 72.8 years). The average duration of symptoms was 2.7 years. Dementia ranged from mild to moderately severe. None had clinical or laboratory evidence of cerebrovascular disease (Hachinski ischemic scores for all patients were 4 or below 4). All received the Wechsler Adult Intelligence Scale (WAIS), Mini-mental State Test (MMS) and Western Aphasia Battery (WAB, First Japanese edition, 1986). Regional cerebral blood flow (rCBF) was evaluated by single photon emission CT (SPECT) with 123 I-N-isopropyl-p-iodoamphetamine ( 123 I-IMP), using the Matsuda's quantitative method. Regional tracer uptake was measured in regions of interests (ROIs) over right and left frontal, temporal, parietal and occipital cortical regions; basal ganglia; and cerebellar hemispheres. The subjects were divided into three groups on the basis of lateral asymmetries in the temporal and parietal cortexes of rCBF (left< right, n=5; right< left, n=3; left=right, n=8). We decided that lateral asymmetry was present when rCBF for each ROI between left and right sides differs by more than 10%. General score (MMS, T-IQ) was not correlated with asymmetry of cerebral blood flow. Verbal IQ in patients with predominant hypoperfusion of left temporal and parietal lobe was significantly lower than other group, while performance IQ and WAB constructive scores were lower in those with right hemispheric hypoperfusion (p<0.05). We concluded that cerebral blood flow asymmetry by SPECT was related significantly to the deficit of language and constructive function in patients with dementia of Alzheimer type. Decreased rCBF in the left temporoparietal lobe was associated with language dysfunction, and that in the right hemisphere, with constructive dysfunction. (author)

Relations between neuropsychological findings and lateral asymmetries of cerebral blood flow measured by SPECT in dementia of Alzheimer type

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Yoshimura, Nahoko; Soma, Yoshiaki; Ootsuki, Mika [Takeda General Hospital, Aizu-Wakamatsu, Fukushima (Japan)

1993-10-01

We studied 16 right-handed patients clinically diagnosed as dementia of Alzheimer type (6 men, 10 women; aged 63-85, mean 72.8 years). The average duration of symptoms was 2.7 years. Dementia ranged from mild to moderately severe. None had clinical or laboratory evidence of cerebrovascular disease (Hachinski ischemic scores for all patients were 4 or below 4). All received the Wechsler Adult Intelligence Scale (WAIS), Mini-mental State Test (MMS) and Western Aphasia Battery (WAB, First Japanese edition, 1986). Regional cerebral blood flow (rCBF) was evaluated by single photon emission CT (SPECT) with {sup 123}I-N-isopropyl-p-iodoamphetamine ({sup 123}I-IMP), using the Matsuda`s quantitative method. Regional tracer uptake was measured in regions of interests (ROIs) over right and left frontal, temporal, parietal and occipital cortical regions; basal ganglia; and cerebellar hemispheres. The subjects were divided into three groups on the basis of lateral asymmetries in the temporal and parietal cortexes of rCBF (leftasymmetry was present when rCBF for each ROI between left and right sides differs by more than 10%. General score (MMS, T-IQ) was not correlated with asymmetry of cerebral blood flow. Verbal IQ in patients with predominant hypoperfusion of left temporal and parietal lobe was significantly lower than other group, while performance IQ and WAB constructive scores were lower in those with right hemispheric hypoperfusion (p<0.05). We concluded that cerebral blood flow asymmetry by SPECT was related significantly to the deficit of language and constructive function in patients with dementia of Alzheimer type. Decreased rCBF in the left temporoparietal lobe was associated with language dysfunction, and that in the right hemisphere, with constructive dysfunction. (author).

Left-right cortical asymmetries of regional cerebral blood flow during listening to words

DEFF Research Database (Denmark)

Nishizawa, Y; Olsen, T S; Larsen, B

1982-01-01

1. Regional cerebral blood flow (rCBF) was measured during rest and during listening to simple words. The xenon-133 intracarotid technique was used and results were obtained from 254 regions of seven right hemispheres and seven left hemispheres. The measurements were performed just after carotid...... of the entire hemisphere. The focal rCBF increases were localized to the superior part of the temporal regions, the prefrontal regions, the frontal eye fields, and the orbitofrontal regions. Significant asymmetries were found in particular in the superior temporal region with the left side showing a more...

Cerebral Asymmetry of fMRI-BOLD Responses to Visual Stimulation.

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Anders Hougaard

Full Text Available Hemispheric asymmetry of a wide range of functions is a hallmark of the human brain. The visual system has traditionally been thought of as symmetrically distributed in the brain, but a growing body of evidence has challenged this view. Some highly specific visual tasks have been shown to depend on hemispheric specialization. However, the possible lateralization of cerebral responses to a simple checkerboard visual stimulation has not been a focus of previous studies. To investigate this, we performed two sessions of blood-oxygenation level dependent (BOLD functional magnetic resonance imaging (fMRI in 54 healthy subjects during stimulation with a black and white checkerboard visual stimulus. While carefully excluding possible non-physiological causes of left-to-right bias, we compared the activation of the left and the right cerebral hemispheres and related this to grey matter volume, handedness, age, gender, ocular dominance, interocular difference in visual acuity, as well as line-bisection performance. We found a general lateralization of cerebral activation towards the right hemisphere of early visual cortical areas and areas of higher-level visual processing, involved in visuospatial attention, especially in top-down (i.e., goal-oriented attentional processing. This right hemisphere lateralization was partly, but not completely, explained by an increased grey matter volume in the right hemisphere of the early visual areas. Difference in activation of the superior parietal lobule was correlated with subject age, suggesting a shift towards the left hemisphere with increasing age. Our findings suggest a right-hemispheric dominance of these areas, which could lend support to the generally observed leftward visual attentional bias and to the left hemifield advantage for some visual perception tasks.

Cerebral Asymmetry of fMRI-BOLD Responses to Visual Stimulation

DEFF Research Database (Denmark)

Hougaard, Anders; Jensen, Bettina Hagström; Amin, Faisal Mohammad

2015-01-01

Hemispheric asymmetry of a wide range of functions is a hallmark of the human brain. The visual system has traditionally been thought of as symmetrically distributed in the brain, but a growing body of evidence has challenged this view. Some highly specific visual tasks have been shown to depend......MRI) in 54 healthy subjects during stimulation with a black and white checkerboard visual stimulus. While carefully excluding possible non-physiological causes of left-to-right bias, we compared the activation of the left and the right cerebral hemispheres and related this to grey matter volume, handedness...... was correlated with subject age, suggesting a shift towards the left hemisphere with increasing age. Our findings suggest a right-hemispheric dominance of these areas, which could lend support to the generally observed leftward visual attentional bias and to the left hemifield advantage for some visual...

[Asymmetries in dynamic plantar pressure distribution measurement in able-bodied gait: application to the study of the gait asymmetries in children with hemiplegic cerebral palsy].

Science.gov (United States)

Femery, V; Moretto, P; Renaut, H; Lensel, G; Thevenon, A

2002-03-01

The aim of this study was to analyse, firstly, the plantar pressure distribution in healthy subjects in order to validate or invalidate the previous studies results on the asymmetrical profile of the stance phase. The studies of asymmetries was based on the identification of a propulsive foot and a loading foot from a concept introduced by Viel. Secondly, the approach was applied to the study of gait asymmetries in two children with hemiplegic cerebral plasy. Thirty healthy control subjects and two hemiplegic children (H1 and H2) performed a walking test at self selected speed. The recordings of dynamic parameters were realized thanks to an in-shoe plantar pressure analysis system (Parotec, by Paromed Medizintechnik, GMBH, Germany). The pressure peaks were determined from the recording of pressures under eight footprint locations. A program calculated the sum of forces under the heel and determined the loading foot. By defect, the second foot is the propulsive foot. The asymmetrical profile of the human normal stance phase was validated. Under the heel, the pressure peaks lower by 28 % were noticed beneath the loading foot compared to the propulsive foot. Inversely, under the metatarsal heads and the hallux, the pressure peaks were greater by 32 % beneath the propulsive foot. For the two hemiplegic children, the plantar pressure profile equally highlighted significant differences between the unaffected and affected feet. The pressure peaks under the affected heel were respectively lower by 21 % and 97 % for H1 and H2. The loading function was found and associated to the affected limb. The propulsive function was not systematically found under the unaffected foot. The analysis of plantar pressure measurements during able-bodied gait showed differences between the two lower limbs. These dynamic asymmetries are the results of a natural functional organization of the supports differentiating a loading foot and a propulsive foot and corroborating the concept proposed by

Detection of misery perfusion in the cerebral hemisphere with chronic unilateral major cerebral artery steno-occlusive disease using crossed cerebellar hypoperfusion: comparison of brain SPECT and PET imaging

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Matsumoto, Yoshiyasu; Ogasawara, Kuniaki; Saito, Hideo; Takahashi, Yoshihiro; Ogasawara, Yasushi; Kobayashi, Masakazu; Ogawa, Akira [Iwate Medical University, Department of Neurosurgery, Morioka (Japan); Iwate Medical University, Cyclotron Research Center, Morioka (Japan); Terasaki, Kazunori [Iwate Medical University, Cyclotron Research Center, Morioka (Japan); Yoshida, Kenji; Beppu, Takaaki; Kubo, Yoshitaka; Fujiwara, Shunrou [Iwate Medical University, Department of Neurosurgery, Morioka (Japan); Tsushima, Eiki [Hirosaki University, Graduate School of Health Sciences, Hirosaki (Japan)

2013-10-15

In patients with unilateral internal carotid or middle cerebral artery (ICA or MCA) occlusive disease, the degree of crossed cerebellar hypoperfusion that is evident within a few months after the onset of stroke may reflect cerebral metabolic rate of oxygen in the affected cerebral hemisphere relative to that in the contralateral cerebral hemisphere. The aim of the present study was to determine whether the ratio of blood flow asymmetry in the cerebellar hemisphere to blood flow asymmetry in the cerebral hemisphere on positron emission tomography (PET) and single photon emission computed tomography (SPECT) correlates with oxygen extraction fraction (OEF) asymmetry in the cerebral hemisphere on PET in patients with chronic unilateral ICA or MCA occlusive disease and whether this blood flow ratio on SPECT detects misery perfusion in the affected cerebral hemisphere in such patients. Brain blood flow and OEF were assessed using {sup 15}O-PET and N-isopropyl-p-[{sup 123}I]iodoamphetamine ({sup 123}I-IMP) SPECT, respectively. All images were anatomically standardized using SPM2. A region of interest (ROI) was automatically placed in the bilateral MCA territories and in the bilateral cerebellar hemispheres using a three-dimensional stereotaxic ROI template, and affected-to-contralateral asymmetry in the MCA territory or contralateral-to-affected asymmetry in the cerebellar hemisphere was calculated. Sixty-three patients with reduced blood flow in the affected cerebral hemisphere on {sup 123}I-IMP SPECT were enrolled in this study. A significant correlation was observed between MCA ROI asymmetry of PET OEF and the ratio of cerebellar hemisphere asymmetry of blood flow to MCA ROI asymmetry of blood flow on PET (r = 0.381, p = 0.0019) or SPECT (r = 0.459, p = 0.0001). The correlation coefficient was higher when reanalyzed in a subgroup of 43 patients undergoing a PET study within 3 months after the last ischemic event (r = 0.541, p = 0.0001 for PET; r = 0.609, p < 0

Step-to-step reproducibility and asymmetry to study gait auto-optimization in healthy and cerebral palsied subjects.

Science.gov (United States)

Descatoire, A; Femery, V; Potdevin, F; Moretto, P

2009-05-01

The purpose of our study was to compare plantar pressure asymmetry and step-to-step reproducibility in both able-bodied persons and two groups of hemiplegics. The relevance of the research was to determine the efficiency of asymmetry and reproducibility as indexes for diagnosis and rehabilitation processes. This study comprised 31 healthy young subjects and 20 young subjects suffering from cerebral palsy hemiplegia assigned to two groups of 10 subjects according to the severity of their musculoskeletal disorders. The peaks of plantar pressure and the time to peak pressure were recorded with an in-shoe measurement system. The intra-individual coefficient of variability was calculated to indicate the consistency of plantar pressure during walking and to define gait stability. The effect size was computed to quantify the asymmetry and measurements were conducted at eight footprint locations. Results indicated few differences in step-to-step reproducibility between the healthy group and the less spastic group while the most affected group showed a more asymmetrical and unstable gait. From the concept of self-optimisation and depending on the neuromotor disorders the organism could make priorities based on pain, mobility, stability or energy expenditure to develop the best gait auto-optimisation.

ASYMMETRY OF THE BRAIN AT ADAPTATION TO HYPOXIA

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V. I. Portnichenko

2012-11-01

Full Text Available Association between cerebral blood flow and higher nervous activity in people at different stages of adaptation to the midlands was studied. Investigation were performed before, during and after a three-week stay in the mountains at an altitude of 2100 m, as well as during short-term ups without the physical load on the height of 3900 m. In the initial period of adaptation to hypoxia desynchronization between the nerve processes in the cerebral cortex and brain blood flow was observed. There was an inversion and an increase in the asymmetry of cerebral blood flow in the direction of the dominance of the left hemisphere of the brain. After the three-week stay in the mountains asymmetry of cerebral blood flow was disappeared, blood flow to the brain was reduced, hemispheric symmetry was formed, and blood flow synchronized with the nerve processes in the cerebral cortex again was restored.

Structural asymmetry of cortical visual areas is related to ocular dominance

DEFF Research Database (Denmark)

Jensen, Bettina H; Hougaard, Anders; Amin, Faisal M

2015-01-01

lateralized visual areas were identified, both right>left and left>right. When correlating the asymmetries to the functional parameters, we found a significant correlation to ocular dominance (P...The grey matter of the human brain is asymmetrically distributed between the cerebral hemispheres. This asymmetry includes visual areas, but its relevance to visual function is not understood. Voxel-based morphometry is a well-established technique for localization and quantification of cerebral...... was identified to be significantly larger in the left hemisphere for right-eyed participants and vice versa. These results suggest a cerebral basis for ocular dominance....

Evaluation of asymmetries of blood flow rate and of circulation time by intravenous radionuclide cerebral angiography in patients with ischemic completed stroke.

Science.gov (United States)

Bartolini, A; Primavera, A; Gasparetto, B

1984-12-01

155 patients with ischemic completed stroke of varying severity and outcome have been evaluated by radionuclide cerebral angiography with analysis of regional time-activity curves. Two parameters have been evaluated: area under the upslope of the curve (Aup) reflecting regional blood flow rate and moment of the whole curve reflecting tracer circulation time (rABCT) Combination of these two methods ensured increased detection of perfusion asymmetries.

Believing in paranormal phenomena: relations to asymmetry of body and brain.

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Schulter, Günter; Papousek, Ilona

2008-01-01

The goal of this study was to investigate the possible relationship between established measures of body and brain asymmetries and individual differences in paranormal beliefs. In addition to behavioural measures of cerebral laterality, measures of facial features and finger length were taken to calculate body asymmetry scores and indicators of fluctuating asymmetry (average absolute differences between left and right body features). Both the direction and degree of laterality measures were used. In addition to that, quantitative measures of inconsistency of cerebral lateralization were obtained. Results indicated that a stronger belief in paranormal phenomena was associated with fluctuating asymmetry of finger length, and that this aspect of body asymmetry may be related to greater intraindividual variability in the degree of 'atypical' functional lateralization. This intraindividual variability index, in turn, significantly predicted strength of belief in the paranormal. Belief in the paranormal was also higher in women than men and it was negatively correlated with the education level. In sum, these findings suggest that a part of the variance of strength of belief in paranormal phenomena can be explained by patterns of functional hemispheric asymmetry that may be related to perturbations during fetal development.

Evidence from intrinsic activity that asymmetry of the human brain is controlled by multiple factors.

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Liu, Hesheng; Stufflebeam, Steven M; Sepulcre, Jorge; Hedden, Trey; Buckner, Randy L

2009-12-01

Cerebral lateralization is a fundamental property of the human brain and a marker of successful development. Here we provide evidence that multiple mechanisms control asymmetry for distinct brain systems. Using intrinsic activity to measure asymmetry in 300 adults, we mapped the most strongly lateralized brain regions. Both men and women showed strong asymmetries with a significant, but small, group difference. Factor analysis on the asymmetric regions revealed 4 separate factors that each accounted for significant variation across subjects. The factors were associated with brain systems involved in vision, internal thought (the default network), attention, and language. An independent sample of right- and left-handed individuals showed that hand dominance affects brain asymmetry but differentially across the 4 factors supporting their independence. These findings show the feasibility of measuring brain asymmetry using intrinsic activity fluctuations and suggest that multiple genetic or environmental mechanisms control cerebral lateralization.

The relationship between skull asymmetry and CT findings

International Nuclear Information System (INIS)

Yamori, Yuriko; Yuge, Mariko; Kanda, Toyoko; Ashida, Hiromi; Fukase, Hiroshi

1987-01-01

In order to clarify the relationship between brain damage and skull asymmetry or supine head position preference, we classified CT findings of 330 cases with cerebral palsy or risk of motor disturbance into 6 groups according to skull shape. Those were severe (I, n = 37) and mild (II, n = 114) grades in the right occipital flatness, severe (III, n = 34) and mild (IV, n = 58) grades in the left occipital flatness, long skull with temporal flatness (V, n = 33) and symmetric round skull (control, n = 54). It was considered that the asymmetry of cortical atrophy in appearance was formed physicaly by skull asymmetry but that the asymmetric dilatation in appearance of lateral ventricle was related to the asymmetry of brain damage. The severity and the asymmetry of brain damage were tend to increase the grade of skull asymmetry. The incidence of cases with the right occipital flatness was 1.6 times more frequently than the left sided. The incidence of cases whose left (lateral) ventricle was larger than the right was 4.1 times more than the cases whose right ventricle was larger than the left. The cases with occipital flatness in the contralateral side of the larger lateral ventricle were found more than the cases with occipital flatness in the ipsilateral side of the larger ventricle, that is to say, the direction of supine head position preference during early infant was suspected to be the more severely disturbed side of body. These results suggest that the supine head position preference to the right in newborn babies and infants with scoliosis or cerebral palsy might be the result of transient or permanent asymmetric (left > right) brain dysfunction. (author)

Increased attentiveness is associated with hemispheric asymmetry measured with lateral tympanic membrane temperature in humans and dogs.

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Helton, William S; Maginnity, Michelle

2012-06-01

In this study, we examined the relationship between a measure of cerebral lateralization--differences in tympanic temperature (T(Ty))--and questionnaire measures of inattentiveness and hyperactivity in both people and dogs. Theories of cerebral lateralization indicate that cerebral asymmetry may improve attentive behaviour. In people, greater left than right T(Ty) was related to increased self-reports of inattentiveness. There was no relationship between lateralized T(Ty) and hyperactivity. In dogs, there was quadratic relationship between lateralized T(Ty) and handler reports of inattentiveness. Increased T(Ty) asymmetry, regardless of direction, was related to more attentiveness. There was no discernable relationship between hyperactivity and lateralized T(Ty). Differences in T(Ty) may be an useful tool for investigating species comparisons of cerebral lateralization.

Cerebral specialization. [greater performance efficiency for certain mental abilities or processes by one cerebral hemisphere over another

Science.gov (United States)

Morris, Robin D.; Hopkins, William D.; Rumbaugh, Duane M.

1991-01-01

The concept of greater performance efficiency for certain mental abilities or processes in one cerebral hemisphere rather than the other is referred to as 'cerebral lateralization'. The experimental paradigm for lateralization research involves the study of patients with one damaged hemisphere, which prevents their performance of a certain task or function; this approach, however, presents many difficulties in extrapolating to brain function in normal patients. Attention is presently given to gender differences in lateralization, cerebral asymmetries in other species, and the evolutionary bases of hemispheric specialization.

Aging effects on cerebral asymmetry: a voxel-based morphometry and diffusion tensor imaging study.

Science.gov (United States)

Takao, Hidemasa; Abe, Osamu; Yamasue, Hidenori; Aoki, Shigeki; Kasai, Kiyoto; Sasaki, Hiroki; Ohtomo, Kuni

2010-01-01

The hemispheres of the human brain are functionally and structurally asymmetric. The purpose of this study was to evaluate the effects of aging on gray and white matter asymmetry. Two hundred twenty-six right-handed normal volunteers aged 21-71 years were included in this study. The effects of aging on gray matter volume asymmetry and white matter fractional anisotropy asymmetry were evaluated with use of voxel-based morphometry and voxel-based analysis of fractional anisotropy maps derived from diffusion tensor imaging (DTI), respectively. The voxel-based morphometry showed no significant correlation between age and gray matter volume asymmetry. The voxel-based analysis of DTI also showed no significant correlation between age and white matter fractional anisotropy asymmetry. Our results showed no significant effects of aging on either gray matter volume asymmetry or white matter fractional anisotropy asymmetry.

Noninvasive xenon-133 measurements of cerebral blood flow using stationary detectors compared with dynamic emission tomography

DEFF Research Database (Denmark)

Schroeder, T; Vorstrup, S; Lassen, N A

1986-01-01

the stationary detectors yielded somewhat lower CBF values than did emission tomography. Considering the side-to-side asymmetry, an excellent correlation was obtained. Using the initial slope index, the stationary detectors revealed quantitatively 83% of the interhemispheric asymmetry and 63% of the asymmetry...... in the middle cerebral artery territory shown with the tomograph. As illustrated by a case history, the nontomographic CBF unit used in this study may provide reliable and useful information in patients with occlusive cerebrovascular disease by performing repeated CBF studies and challenging the cerebral...

Quantitative Analysis of Regional Cerebral Blood Flow using 99mTc-HMPAO SPECT in Parkinson's Disease

International Nuclear Information System (INIS)

Lee, Myung Chul; Bae, Sang Kyun; Chung, June Key; Koh, Chang Soon; Roh, Jae Kyu; Myung, Ho Jin; Lee, Myung Hae

1992-01-01

Regional cerebral blood flow were measured in 10 patients with Parkinson's disease and 12 normal persons using 99m Tc-HMPAO SPECT. Reconstructed images were interpreted qualitatively and were compared with those findings of CT. For the quantitative analysis, six pairs of region of interest matched with the perfusion territories of large cerebral arteries and cerebellar hemisphere were determined. From the count values, indices showing the degree of asymmetry between right and left cerebral or cerebellar hemisphere, cerebral asymmetry index (ASI) and percent index of cerebellar asymmetry (PIA), and an index showing change of each region, region to cerebellum ratio (RCR) were obtained. ASI of normal persons and patients were 0.082 ± 0.033 and 0.108 ± 0.062, respectively and PIA were -0.4 ± 0.7% and -0.7 ± 1.0%, respectively, which showed no statistically significant difference between normal persons and patients. Among 10 RCR's, those of both regions of basal ganglia and both regions of anterior cerebral artery were significantly reduced. We concluded that the most significant reduction of regional cerebral blood flow in patients with Parkinson's disease was observed in the regions of basal ganglia and in the regions of anterior cerebral artery, and the degree of change in hemispheric blood flow was similar in both hemisphere.

Evidence from intrinsic activity that asymmetry of the human brain is controlled by multiple factors

OpenAIRE

Liu, Hesheng; Stufflebeam, Steven M.; Sepulcre, Jorge; Hedden, Trey; Buckner, Randy L.

2009-01-01

Cerebral lateralization is a fundamental property of the human brain and a marker of successful development. Here we provide evidence that multiple mechanisms control asymmetry for distinct brain systems. Using intrinsic activity to measure asymmetry in 300 adults, we mapped the most strongly lateralized brain regions. Both men and women showed strong asymmetries with a significant, but small, group difference. Factor analysis on the asymmetric regions revealed 4 separate factors that each ac...

Quantitative Analysis of Regional Cerebral Blood Flow using {sup 99m}Tc-HMPAO SPECT in Parkinson's Disease

Energy Technology Data Exchange (ETDEWEB)

Lee, Myung Chul; Bae, Sang Kyun; Chung, June Key; Koh, Chang Soon; Roh, Jae Kyu; Myung, Ho Jin [Seoul National University College of Medicine, Seoul (Korea, Republic of); Lee, Myung Hae [Asan Medical Center, Seoul (Korea, Republic of)

1992-07-15

Regional cerebral blood flow were measured in 10 patients with Parkinson's disease and 12 normal persons using {sup 99m}Tc-HMPAO SPECT. Reconstructed images were interpreted qualitatively and were compared with those findings of CT. For the quantitative analysis, six pairs of region of interest matched with the perfusion territories of large cerebral arteries and cerebellar hemisphere were determined. From the count values, indices showing the degree of asymmetry between right and left cerebral or cerebellar hemisphere, cerebral asymmetry index (ASI) and percent index of cerebellar asymmetry (PIA), and an index showing change of each region, region to cerebellum ratio (RCR) were obtained. ASI of normal persons and patients were 0.082 +- 0.033 and 0.108 +- 0.062, respectively and PIA were -0.4 +- 0.7% and -0.7 +- 1.0%, respectively, which showed no statistically significant difference between normal persons and patients. Among 10 RCR's, those of both regions of basal ganglia and both regions of anterior cerebral artery were significantly reduced. We concluded that the most significant reduction of regional cerebral blood flow in patients with Parkinson's disease was observed in the regions of basal ganglia and in the regions of anterior cerebral artery, and the degree of change in hemispheric blood flow was similar in both hemisphere.

Asymmetry of critical closing pressure following head injury

OpenAIRE

Kumar, A; Schmidt, E; Hiler, M; Smielewski, P; Pickard, J; Czosnyka, M

2005-01-01

Objective: Critical closing pressure (CCP) is the arterial pressure below which the vessels collapse. Hypothetically it is the sum of intracranial pressure (ICP) and vessel wall tension in the cerebral circulation. This study investigated transhemispherical asymmetry of CCP by studying its correlation with radiological findings on computed tomography (CT) scans in head injury patients.

Cerebral perfusion in homogeneity in normal volunteers

International Nuclear Information System (INIS)

Gruenwald, S.M.; Larcos, G.

1998-01-01

Full text: In the interpretation of cerebral perfusion scans, it is important to know the normal variation in perfusion which may occur between the cerebral hemispheres. For this reason 24 normal volunteers with no neurological or psychiatric history, and who were on no medications, had 99m Tc-HMPAO brain SPECT studies using a single headed gamma camera computer system. Oblique, coronal and sagittal images were reviewed separately by two experienced observers and any differences were resolved by consensus. Semi-quantitation was performed by summing two adjacent oblique slices and drawing right and left mirror image ROIs corresponding to the mid section level of anterior and posterior frontal lobes, anterior and posterior parietal lobes, temporal lobes and cerebellum. From the mean counts per pixel, right: left ROI ratios and ROI: cerebellar ratios were calculated. On qualitative review 6/24 subjects had mild asymmetry in tracer distribution between right and left cerebral lobes. Semi-quantitation revealed a 5-10% difference in counts between right and left ROIs in 12/24 subjects and an additional three subjects had 10-20% difference in counts between right and left temporal lobes. This study demonstrates the presence of mild asymmetry of cerebral perfusion in a significant minority of normal subjects

Sexual orientation differences in cerebral asymmetry and in the performance of sexually dimorphic cognitive and motor tasks.

Science.gov (United States)

Sanders, G; Wright, M

1997-10-01

With each of the tasks in the present studies we expected to find the reported sex difference between heterosexual women and heterosexual men and we predicted a sexual orientation effect with the performance of homosexual men being similar to that of heterosexual women and different from that of heterosexual men. Study 1 aimed to replicate earlier findings by recording the performance of a group of homosexual men on a visuospatial task, the Vincent Mechanical Diagrams Test (VMDT), a dot detection divided visual field measure of functional cerebral asymmetry, and on five subtests of the Wechsler Adult Intelligence Scale (WAIS). For each task the profile of scores obtained for the homosexual men was similar to that of heterosexual women in that they scored lower than heterosexual men on the VMDT, they showed less asymmetry, and they recorded a higher Verbal than Performance IQ on the WAIS. In Study 2, a male-biased targeted throwing task favored heterosexual men while, in contrast, on the female-biased Purdue Pegboard single peg condition heterosexual men were outperformed by heterosexual women and homosexual men. On neither of these two tasks did the performances of homosexual men and heterosexual women differ. One task, manual speed, yielded neither sex nor sexual orientation differences. Another, the Purdue Pegboard assemblies condition, revealed a sex difference but no sexual orientation difference. Failure to obtain a sexual orientation difference in the presence of a sex difference suggests that the sexual orientation effect may be restricted to a subset of sexually dimorphic tasks.

Prevalence of lateral ventricle asymmetry in brain MRI studies of neurologically normal dogs and dogs with idiopathic epilepsy.

Science.gov (United States)

Pivetta, Mauro; De Risio, Luisa; Newton, Richard; Dennis, Ruth

2013-01-01

Asymmetry of the cerebral lateral ventricles is a common finding in cross-sectional imaging of otherwise normal canine brains and has been assumed to be incidental. The purpose of this retrospective study was to compare the prevalence of ventricular asymmetry in brain MRI studies of normal dogs and dogs with idiopathic epilepsy. Brain MRI archives were searched for 100 neurologically normal dogs (Group 1) and 100 dogs with idiopathic epilepsy (Group 2). For each dog, asymmetry of the lateral ventricles was subjectively classified as absent, mild, moderate, and severe based on a consensus of two observers who were unaware of group status. Ventricular areas were measured from transverse T1W images at the level of the interthalamic adhesion. An asymmetry ratio was calculated as the ratio of the larger to smaller ventricular transverse area. There was excellent agreement between subjective assessments of ventricular asymmetry and quantitative assessments using asymmetry ratios (k = 0.995). The prevalence of asymmetry was 38% in Group 1 dogs and 44% in Group 2 dogs. Assymmetry was scored as mild in the majority of Group 2 dogs. There was no significant association between presence/absence and degree of ventricular asymmetry vs. dog group, age, gender, or skull conformation. Findings from the current study supported previously published assumptions that asymmetry of the lateral cerebral ventricles is an incidental finding in MRI studies of the canine brain. © 2013 Veterinary Radiology & Ultrasound.

Age-Related Differences in Bilateral Asymmetry in Cycling Performance

Science.gov (United States)

Liu, Ting; Jensen, Jody L.

2012-01-01

Bilateral asymmetry, a form of limb laterality in the context of moving two limbs, emerges in childhood. Children and adults show lateral preference in tasks that involve the upper and lower limbs. The importance of research in limb laterality is the insight it could provide about lateralized functions of the cerebral hemispheres. Analyzing…

Asymmetry, Symmetry and Beauty

Directory of Open Access Journals (Sweden)

Abbe R. Kopra

2010-07-01

Full Text Available Asymmetry and symmetry coexist in natural and human processes.  The vital role of symmetry in art has been well demonstrated. This article highlights the complementary role of asymmetry. Further we show that the interaction of asymmetric action (recursion and symmetric opposition (sinusoidal waves are instrumental in generating creative features (relatively low entropy, temporal complexity, novelty (less recurrence in the data than in randomized copies and complex frequency composition. These features define Bios, a pattern found in musical compositions and in poetry, except for recurrence instead of novelty. Bios is a common pattern in many natural and human processes (quantum processes, the expansion of the universe, gravitational waves, cosmic microwave background radiation, DNA, physiological processes, animal and human populations, and economic time series. The reduction in entropy is significant, as it reveals creativity and contradicts the standard claim of unavoidable decay towards disorder. Artistic creations capture fundamental features of the world.

Auditory Evoked Potentials and Hand Preference in 6-Month-Old Infants: Possible Gender-Related Differences in Cerebral Organization.

Science.gov (United States)

Shucard, Janet L.; Shucard, David W.

1990-01-01

Verbal and musical stimuli were presented to infants in a study of the relations of evoked potential left-right amplitude asymmetries to gender and hand preference. There was a relation between asymmetry and hand preference, and for girls, between asymmetry and stimulus condition. Results suggest a gender difference in cerebral hemisphere…

Asymmetry in the brain influenced the neurological deficits and infarction volume following the middle cerebral artery occlusion in rats

Directory of Open Access Journals (Sweden)

Zhang Meizeng

2008-12-01

Full Text Available Abstract Background Paw preference in rats is similar to human handedness, which may result from dominant hemisphere of rat brain. However, given that lateralization is the uniqueness of the humans, many researchers neglect the differences between the left and right hemispheres when selecting the middle cerebral artery occlusion (MCAO in rats. The aim of this study was to evaluate the effect of ischemia in the dominant hemisphere on neurobehavioral function and on the cerebral infarction volume following MCAO in rats. Methods The right-handed male Sprague-Dawley rats asserted by the quadrupedal food-reaching test were subjected to 2 hours MCA occlusion and then reperfusion. Results The neurological scores were significantly worse in the left MCAO group than that in the right MCAO group at 1 h, 24 h, 48 h and 72 h (p 0.05 respectively. There was a trend toward better neurobehavioral function recovery in the right MCAO group than in the left MCAO group. The total infarct volume in left MCAO was significantly larger than that in the right (p Conclusion The neurobehavioral function result and the pathological result were consistent with the hypothesis that paw preference in rats is similar to human handedness, and suggested that ischemia in dominant hemisphere caused more significant neurobehavioral consequence than in another hemisphere following MCAO in adult rats. Asymmetry in rat brain should be considered other than being neglected in choice of rat MCAO model.

Dyke-Davidoff-Masson syndrome: case report of fetal unilateral ventriculomegaly and hypoplastic left middle cerebral artery

OpenAIRE

Piro, Ettore; Piccione, Maria; Marrone, Gianluca; Giuffr?, Mario; Corsello, Giovanni

2013-01-01

Prenatal ultrasonographic detection of unilateral cerebral ventriculomegaly arises suspicion of pathological condition related to cerebrospinal fluid flow obstruction or cerebral parenchimal pathology. Dyke-Davidoff-Masson syndrome is a rare condition characterized by cerebral hemiatrophy, calvarial thickening, skull and facial asymmetry, contralateral hemiparesis, cognitive impairment and seizures. Congenital and acquired types are recognized and have been described, mainly in late childhood...

Cerebral asymmetry in patients with schizophrenia: a voxel-based morphometry (VBM) and diffusion tensor imaging (DTI) study.

Science.gov (United States)

Takao, Hidemasa; Abe, Osamu; Yamasue, Hidenori; Aoki, Shigeki; Kasai, Kiyoto; Ohtomo, Kuni

2010-01-01

To evaluate the differences in gray- and white-matter asymmetry between schizophrenia patients and normal subjects. Forty-eight right-handed patients with chronic schizophrenia (24 males and 24 females) and 48 right-handed age- and sex-matched healthy controls (24 males and 24 females) were included in this study. The effects of diagnosis on gray-matter volume asymmetry and white-matter fractional anisotropy (FA) asymmetry were evaluated with use of voxel-based morphometry (VBM) and voxel-based analysis of FA maps derived from diffusion tensor imaging (DTI), respectively. The mean gray- and white-matter volumes were significantly smaller in the schizophrenia group than in the control group. The voxel-based morphometry (VBM) showed no significant effect of diagnosis on gray-matter volume asymmetry. The voxel-based analysis of DTI also showed no significant effect of diagnosis on white-matter FA asymmetry. Our results of voxel-based analyses showed no significant differences in either gray-matter volume asymmetry or white-matter FA asymmetry between schizophrenia patients and normal subjects. (c) 2009 Wiley-Liss, Inc.

A study of cerebral circulation in elderly patients with dementia using sup 123 I-IMP SPECT

Energy Technology Data Exchange (ETDEWEB)

Arai, Hisayuki [Tokyo Medical Coll. (Japan)

1991-03-01

In order to elucidate the pathogenesis of senile dementia of Alzheimer type (SDAT) and multi-infarct dementia (MID), 18 age-matched controls, 22 SDAT cases, 10 MID cases, and 15 multiple infarction without dementia (MI) cases, totaling 65 cases, were enrolled into a study of cerebral blood flow using single photon emission CT (SPECT) with N-isopropyl-p-({sup 123}I)iodoamphetamine (IMP). The diagnosis of dementia was made based on the clinical history, findings of brain CT, MRI, and Hachinski's ischemic score. Lateral asymmetric perfusion was evaluated by using the asymmetry index (AI). Quantitative cerebral blood flow was analyzed by using the venous blood sampling method with IMP SPECT. Cerebral infarction, ischemic changes, and brain atrophy were diagnosed by CT and MRI. mCBF values were significantly lower in SDAT and MID than in those of controls, while rCBF values were lowest at the frontal lobes in MID and at the parietal lobes in SDAT. Hasegawa's dementia score was correlated with the rCBF at the frontal lobes in MID. In MID, there was a greater number of infarction, and atrophic changes were significantly remarkable, while the rCBF values were significantly lower at the frontal lobes compared to the MI group. Multi-variate analysis suggested that among the factors contributing to MID, brain atrophy was most relevant to dementia. In SDAT, rCBF values showed the most lateral asymmetry at the parietal lobes, the least, at the occipital lobes. The lateral asymmetry of the cerebral blood flow at the parietal lobes showed an association with clinical symptoms. There was a negative coefficiency between the cerebellum and the cerebral hemisphere in the evaluation of lateral asymmetry. These results suggest that rCBF estimation by IMP SPECT is useful in the differential diagnosis between MID and SDAT, and may also contribute to the classification of these two diseases. (author).

Hemispheric Asymmetry of Human Brain Anatomical Network Revealed by Diffusion Tensor Tractography

Directory of Open Access Journals (Sweden)

Ni Shu

2015-01-01

Full Text Available The topological architecture of the cerebral anatomical network reflects the structural organization of the human brain. Recently, topological measures based on graph theory have provided new approaches for quantifying large-scale anatomical networks. However, few studies have investigated the hemispheric asymmetries of the human brain from the perspective of the network model, and little is known about the asymmetries of the connection patterns of brain regions, which may reflect the functional integration and interaction between different regions. Here, we utilized diffusion tensor imaging to construct binary anatomical networks for 72 right-handed healthy adult subjects. We established the existence of structural connections between any pair of the 90 cortical and subcortical regions using deterministic tractography. To investigate the hemispheric asymmetries of the brain, statistical analyses were performed to reveal the brain regions with significant differences between bilateral topological properties, such as degree of connectivity, characteristic path length, and betweenness centrality. Furthermore, local structural connections were also investigated to examine the local asymmetries of some specific white matter tracts. From the perspective of both the global and local connection patterns, we identified the brain regions with hemispheric asymmetries. Combined with the previous studies, we suggested that the topological asymmetries in the anatomical network may reflect the functional lateralization of the human brain.

[Correlation between indices of 24-h monitoring of blood pressure and disturbed venous cerebral outflow in hypertensive patients].

Science.gov (United States)

Afanas'eva, N L; Mordovin, V F; Semke, G V; Luk'ianenok, P I

2008-01-01

To study relations between disturbances of cerebral venous circulation and parameters of 24-h blood pressure monitoring in hypertensive patients. A total of 72 patients aged 28 to 60 years with essential hypertension of stage II have undergone 24-h blood pressure monitoring and MR-venography of the brachiocephalic veins on a low-field MR-tomograph using 2D TOF angiography. Symptoms of disturbed cerebral venous circulation were found in 60% patients. Major venous collectors were asymmetric in 79.2% patients, 40.3% had marked asymmetry, 14% had severe asymmetry. Disturbances of venous outflow significantly more frequently occurred in non-dippers and night-peakers as well as in high variability of blood pressure. Patients with marked asymmetry of venous collectors had elevated nocturnal systolic and diastolic blood pressure, high load indices of nocturnal systolic and diastolic pressure, a low degree of nocturnal fall of blood pressure. Disturbance of venous cerebral outflow in hypertensive patients is closely related with alterations of a circadian profile of blood pressure: circadian index of blood pressure, variability of blood pressure.

Response inhibition is modulated by functional cerebral asymmetries for facial expression perception

Directory of Open Access Journals (Sweden)

Sebastian eOcklenburg

2013-11-01

Full Text Available The efficacy of executive functions is critically modulated by information processing in earlier cognitive stages. For example, initial processing of verbal stimuli in the language-dominant left-hemisphere leads to more efficient response inhibition than initial processing of verbal stimuli in the non-dominant right hemisphere. However, it is unclear whether this organizational principle is specific for the language system, or a general principle that also applies to other types of lateralized cognition. To answer this question, we investigated the neurophysiological correlates of early attentional processes, facial expression perception and response inhibition during tachistoscopic presentation of facial ‘Go’ and ‘Nogo’ stimuli in the left and the right visual field. Participants committed fewer false alarms after Nogo-stimulus presentation in the left compared to the right visual field. This right-hemispheric asymmetry on the behavioral level was also reflected in the neurophysiological correlates of face perception, specifically in a right-sided asymmetry in the N170 amplitude. Moreover, the right-hemispheric dominance for facial expression processing also affected event-related potentials typically related to response inhibition, namely the Nogo-N2 and Nogo-P3. These findings show that an effect of hemispheric asymmetries in early information processing on the efficacy of higher cognitive functions is not limited to left-hemispheric language functions, but can be generalized to predominantly right-hemispheric functions.

PET and SPECT in medically non-refractory complex partial seizures. Temporal asymmetries of glucose consumption, Benzodiazepine receptor density

International Nuclear Information System (INIS)

Matheja, P.; Kuwert, T.; Wolf, K.; Schober, O.; Stodieck, S.R.G.; Diehl, B.; Ringelstein, E.B.; Schuierer, G.

1998-01-01

Aim: In contrast to medically refractory complex partial seizures (CPS), only limited knowledge exists on cerebral perfusion and metabolism in medically non-refractory CPS. The aim of this study was to investigate the frequency of temporal asymmetries in regional cerebral glucose consumption (rCMRGlc), regional cerebral blood flow (rCBF), and regional cerebral benzodiazepine receptor density (BRD) in this group of patients. Methods: The study included 49 patients with medically non-refractory cryptogenic CPS (age: 36.0±16.1 years). rCMRGlc was studied with F-18-FDG-PET (FDG), rCBF with Tc-99m-ECD-SPECT (ECD), and BRD with I-123-iomazenil-SPECT (IMZ). All studies were performed interictally and within four weeks in each patient. Duration of epilepsy ranged from 0.1 to 42 years (median 4.0 years). SPECT was performed with the triple-headed SPECT camera Multispect 3, PET with the PET camera ECAT EXACT 47. Using linear profiles, glucose consumption, as well as uptake of ECD and IMZ, were measured in four temporal regions of interest (ROIs), and asymmetry indices were calculated (ASY). The results were compared to 95% confidence intervals determined in control subjects. Results: Thirty-five of the 49 (71%) patients had at least one significantly elevated ASY; temporal rCMRGlc was asymmetrical in 41% of the patients, temporal BRD in 29%, and temporal rCBF in 24%. One patient had an asymmetry of all three variables, two of temporal rCMRGlc and BRD, three of temporal rCMRGlc and rCBF, and another four of rCBF and BRD. Fourteen patients had an isolated temporal asymmetry in rCMRGlc, seven in BRD, and four in rCBF. A discrepancy in lateralization between the three modalities was not observed. Conclusion: The majority of patients with medically non-refractory CPS have focal abnormalities of blood flow and metabolism in their temporal lobe. In this group of patients, FDG-PET demonstrates abnormalities with the highest frequency of the three modalities studied, followed by IMZ

Structural connectivity asymmetry in the neonatal brain.

Science.gov (United States)

Ratnarajah, Nagulan; Rifkin-Graboi, Anne; Fortier, Marielle V; Chong, Yap Seng; Kwek, Kenneth; Saw, Seang-Mei; Godfrey, Keith M; Gluckman, Peter D; Meaney, Michael J; Qiu, Anqi

2013-07-15

Asymmetry of the neonatal brain is not yet understood at the level of structural connectivity. We utilized DTI deterministic tractography and structural network analysis based on graph theory to determine the pattern of structural connectivity asymmetry in 124 normal neonates. We tracted white matter axonal pathways characterizing interregional connections among brain regions and inferred asymmetry in left and right anatomical network properties. Our findings revealed that in neonates, small-world characteristics were exhibited, but did not differ between the two hemispheres, suggesting that neighboring brain regions connect tightly with each other, and that one region is only a few paths away from any other region within each hemisphere. Moreover, the neonatal brain showed greater structural efficiency in the left hemisphere than that in the right. In neonates, brain regions involved in motor, language, and memory functions play crucial roles in efficient communication in the left hemisphere, while brain regions involved in emotional processes play crucial roles in efficient communication in the right hemisphere. These findings suggest that even at birth, the topology of each cerebral hemisphere is organized in an efficient and compact manner that maps onto asymmetric functional specializations seen in adults, implying lateralized brain functions in infancy. Copyright © 2013 Elsevier Inc. All rights reserved.

Transcranial Doppler ultrasound and cerebral angiography - alternative or complementary

International Nuclear Information System (INIS)

Bockenheimer, S.; Lorey, N.

1985-01-01

Transcranial Doppler ultrasound is a noninvasive method of recording the flow velocity of larger intracranial vessels. The impact on diagnosis of cerebravascular occlusive disease is not yet evaluated. We present 15 patients, age range 39-73 years, who suffered from completed stroke. The findings of transcranial Doppler ultrasound and of cerebral angiography are presented. The value of both methods in treatment strategy is discussed. (orig.) [de

The Role of Hemispheral Asymmetry and Regional Activity of Quantitative EEG in Children with Stuttering

Science.gov (United States)

Ozge, Aynur; Toros, Fevziye; Comelekoglu, Ulku

2004-01-01

We investigated the role of delayed cerebral maturation, hemisphere asymmetry and regional differences in children with stuttering and healthy controls during resting state and hyperventilation, using conventional EEG techniques and quantitative EEG (QEEG) analysis. This cross-sectional case control study included 26 children with stuttering and…

[Dextrals and sinistrals (right-handers and left-handers): specificity of interhemispheric brain asymmetry and EEG coherence parameters].

Science.gov (United States)

Zhavoronkova, L A

2007-01-01

Data of literature about morphological, functional and biochemical specificity of the brain interhemispheric asymmetry of healthy right-handers and left-handers and about peculiarity of dynamics of cerebral pathology in patients with different individual asymmetry profiles are presented at the present article. Results of our investigation by using coherence parameters of electroencephalogram (EEG) in healthy right-handers and left-handers in state of rest, during functional tests and sleeping and in patients with different forms of the brain organic damage were analyzed too. EEG coherence analysis revealed the reciprocal changing of alpha-beta and theta-delta spectral bands in right-handers whilein left-handers synchronous changing of all EEG spectral bands were observed. Data about regional-frequent specificity of EEG coherence, peculiarity of EEG asymmetry in right-handers and left-handers, aslo about specificity of EEG spectral band genesis and point of view about a role of the brain regulator systems in forming of interhemispheric asymmetry in different functional states allowed to propose the conception about principle of interhermispheric brain asymmetry formation in left-handers and left-handers. Following this conception in dextrals elements of concurrent (summary-reciprocal) cooperation are predominant at the character of interhemispheric and cortical-subcortical interaction while in sinistrals a principle of concordance (supplementary) is preferable. These peculiarities the brain organization determine, from the first side, the quicker revovery of functions damaged after cranio-cerebral trauma in left-handers in comparison right-handers and from the other side - they determine the forming of the more expressed pathology in the remote terms after exposure the low dose of radiation.

Cerebral glucose metabolism in Wernicke's, Broca's, and conduction aphasia

International Nuclear Information System (INIS)

Metter, E.J.; Kempler, D.; Jackson, C.; Hanson, W.R.; Mazziotta, J.C.; Phelps, M.E.

1989-01-01

Cerebral glucose metabolism was evaluated in patients with either Wernicke's (N = 7), Broca's (N = 11), or conduction (N = 10) aphasia using 18 F-2-fluoro-2-deoxy-D-glucose with positron emission tomography. The three aphasic syndromes differed in the degree of left-to-right frontal metabolic asymmetry, with Broca's aphasia showing severe asymmetry and Wernicke's aphasia mild-to-moderate metabolic asymmetry, while patients with conduction aphasia were metabolically symmetric. On the other hand, the three syndromes showed the same degree of metabolic decline in the left temporal region. The parietal region appeared to separate conduction aphasia from both Broca's and Wernicke's aphasias. Common aphasic features in the three syndromes appear to be due to common changes in the temporal region, while unique features were associated with frontal and parietal metabolic differences

Reduced frontal and occipital lobe asymmetry on the CT-scans of schizophrenic patients. Its specificity and clinical significance

International Nuclear Information System (INIS)

Falkai, P.; Schneider, T.; Greve, B.; Klieser, E.; Bogerts, B.

1995-01-01

Frontal and occipital lobe widths were determined in the computed tomographic (CT) scans of 135 schizophrenic patients, 158 neuro psychiatrically healthy and 102 psychiatric control subjects, including patients with affective psychosis, neurosis and schizoaffective psychosis. Most healthy right-handed subjects demonstrate a relative enlargement of the right frontal as well as left occipital lobe compared to the opposite hemisphere. These normal frontal and occipital lobe asymmetries were selectively reduced in schizophrenics (f.: 5%, p < .0005; o.: 3%, p < .05), irrespective of the pathophysiological subgroup. Schizophrenic neuroleptic non-responders revealed a significant reduction of frontal lobe asymmetry (3%, p < .05), while no correlation between BPRS-sub scores and disturbed cerebral laterality could be detected. In sum the present study demonstrates the disturbed cerebral lateralisation in schizophrenic patients supporting the hypothesis of interrupted early brain development in schizophrenia. (author)

Functional Asymmetries Revealed in Visually Guided Saccades: An fMRI Study

Energy Technology Data Exchange (ETDEWEB)

Petit, L.; Zago, L.; Vigneau, M.; Crivello, F.; Mazoyer, B.; Mellet, E.; Tzourio-Mazoyer, N. [Centre for Imaging, Neurosciences and Applications to Pathologies, UMR6232 CNRS CEA (France); Mazoyer, B. [Centre Hospitalier Universitaire, Caen (France); Andersson, F. [Institut Federatif de Recherche 135, Imagerie fonctionnelle, Tours (France); Mazoyer, B. [Institut Universitaire de France, Paris (France)

2009-07-01

Because eye movements are a fundamental tool for spatial exploration, we hypothesized that the neural bases of these movements in humans should be under right cerebral dominance, as already described for spatial attention. We used functional magnetic resonance imaging in 27 right-handed participants who alternated central fixation with either large or small visually guided saccades (VGS), equally performed in both directions. Hemispheric functional asymmetry was analyzed to identify whether brain regions showing VGS activation elicited hemispheric asymmetries. Hemispheric anatomical asymmetry was also estimated to assess its influence on the VGS functional lateralization. Right asymmetrical activations of a saccadic/attentional system were observed in the lateral frontal eye fields (FEF), the anterior part of the intra-parietal sulcus (aIPS), the posterior third of the superior temporal sulcus (STS), the occipito-temporal junction (MT/V5 area), the middle occipital gyrus, and medially along the calcarine fissure (V1). The present rightward functional asymmetries were not related to differences in gray matter (GM) density/sulci positions between right and left hemispheres in the pre-central, intra-parietal, superior temporal, and extrastriate regions. Only V1 asymmetries were explained for almost 20% of the variance by a difference in the position of the right and left calcarine fissures. Left asymmetrical activations of a saccadic motor system were observed in the medial FEF and in the motor strip eye field along the Rolando sulcus. They were not explained by GM asymmetries. We suggest that the leftward saccadic motor asymmetry is part of a general dominance of the left motor cortex in right-handers, which must include an effect of sighting dominance. Our results demonstrate that, although bilateral by nature, the brain network involved in the execution of VGSs, irrespective of their direction, presented specific right and left asymmetries that were not related to

Functional Asymmetries Revealed in Visually Guided Saccades: An fMRI Study

International Nuclear Information System (INIS)

Petit, L.; Zago, L.; Vigneau, M.; Crivello, F.; Mazoyer, B.; Mellet, E.; Tzourio-Mazoyer, N.; Mazoyer, B.; Andersson, F.; Mazoyer, B.

2009-01-01

Because eye movements are a fundamental tool for spatial exploration, we hypothesized that the neural bases of these movements in humans should be under right cerebral dominance, as already described for spatial attention. We used functional magnetic resonance imaging in 27 right-handed participants who alternated central fixation with either large or small visually guided saccades (VGS), equally performed in both directions. Hemispheric functional asymmetry was analyzed to identify whether brain regions showing VGS activation elicited hemispheric asymmetries. Hemispheric anatomical asymmetry was also estimated to assess its influence on the VGS functional lateralization. Right asymmetrical activations of a saccadic/attentional system were observed in the lateral frontal eye fields (FEF), the anterior part of the intra-parietal sulcus (aIPS), the posterior third of the superior temporal sulcus (STS), the occipito-temporal junction (MT/V5 area), the middle occipital gyrus, and medially along the calcarine fissure (V1). The present rightward functional asymmetries were not related to differences in gray matter (GM) density/sulci positions between right and left hemispheres in the pre-central, intra-parietal, superior temporal, and extrastriate regions. Only V1 asymmetries were explained for almost 20% of the variance by a difference in the position of the right and left calcarine fissures. Left asymmetrical activations of a saccadic motor system were observed in the medial FEF and in the motor strip eye field along the Rolando sulcus. They were not explained by GM asymmetries. We suggest that the leftward saccadic motor asymmetry is part of a general dominance of the left motor cortex in right-handers, which must include an effect of sighting dominance. Our results demonstrate that, although bilateral by nature, the brain network involved in the execution of VGSs, irrespective of their direction, presented specific right and left asymmetries that were not related to

A pattern of cerebral perfusion anomalies between Major Depressive Disorder and Hashimoto Thyroiditis

Science.gov (United States)

2011-01-01

Background This study aims to evaluate relationship between three different clinical conditions: Major Depressive Disorders (MDD), Hashimoto Thyroiditis (HT) and reduction in regional Cerebral Blood Flow (rCBF) in order to explore the possibility that patients with HT and MDD have specific pattern(s) of cerebral perfusion. Methods Design: Analysis of data derived from two separate data banks. Sample: 54 subjects, 32 with HT (29 women, mean age 38.8 ± 13.9); 22 without HT (19 women, mean age 36.5 ± 12.25). Assessment: Psychiatric diagnosis was carried out by Simplified Composite International Diagnostic Interview (CIDIS) using DSM-IV categories; cerebral perfusion was measured by 99 mTc-ECD SPECT. Statistical analysis was done through logistic regression. Results MDD appears to be associated with left frontal hypoperfusion, left temporal hypoperfusion, diffuse hypoperfusion and parietal perfusion asymmetry. A statistically significant association between parietal perfusion asymmetry and MDD was found only in the HT group. Conclusion In HT, MDD is characterized by a parietal flow asymmetry. However, the specificity of rCBF in MDD with HT should be confirmed in a control sample with consideration for other health conditions. Moreover, this should be investigated with a longitudinally designed study in order to determine a possible pathogenic cause. Future studies with a much larger sample size should clarify whether a particular perfusion pattern is associated with a specific course or symptom cluster of MDD. PMID:21910915

Cerebral hyperperfusion following carotid endarterectomy

DEFF Research Database (Denmark)

Schroeder, T; Sillesen, H; Sørensen, O

1987-01-01

, occurred in the low pressure ratio group, while the hemispheric asymmetry on average was unchanged in the high pressure ratio group. This relative hyperemia was most pronounced 2 to 4 days following reconstruction. The marked hyperemia, absolute as well as relative, in patients with a low ICA/CCA pressure...... ratio suggests a temporary impairment of autoregulation. Special care should be taken to avoid postoperative hypertension in such patients, who typically have preoperative hypoperfusion, to avoid the occurrence of cerebral edema or hemorrhage....

Mild cognitive disorders are associated with different patterns of brain asymmetry than normal ageing: the PATH through life study

Directory of Open Access Journals (Sweden)

Nicolas Cherbuin

2010-05-01

Full Text Available Background and Purpose: Defining how brain structures differ in pre-clinical dementia is important to better understand the pathological processes involved and to inform clinical practice. The aim of this study was to identify significant brain correlates (volume and asymmetry in volume of mild cognitive disorders when compared to normal controls in a large community-based sample of young-old individuals who were assessed for cognitive impairment. Methods: Cortical and sub-cortical volumes were measured using a semi-automated method in 398 participants aged 65-70 years who were selected from a larger randomly sampled cohort and who agreed to undergo an MRI scan. Diagnoses were reached based on established protocols for MCI and a more inclusive category of any Mild Cognitive Disorder (any-MCD: which includes AAMI, AACD, OCD, MNC, CDR, MCI. Logistic regression analyses were used to assess the relationship between volume and asymmetry of theoretically relevant cerebral structures (predictors and MCI or any-MCD while controlling for age, sex, and intra-cranial volume. Results: The main correlates of cognitive impairment assessed in multivariate analyses were hippocampal asymmetry (more to left, MCI: OR 0.83, 95%CI 0.71-0.96, p = .013; MCD: OR 0.86, 95%CI 0.77-0.97, p = .011, lateral ventricle asymmetry (more to left, MCI: OR 0.95, 95%CI 0.91-0.99, p = .009; MCD: OR 0.95, 95%CI 0.92-0.98, p = .004, and cerebellar cortex asymmetry (more to left, MCI: OR 1.51, 95%CI 1.13-2.01, p = .005. Conclusions: In this population-based cohort stronger associations were found between asymmetry measures, rather than raw volumes in cerebral structures, and mild cognitive disorders.

Effect of unilateral dominance of the cerebral hemispheres on the radiographic appearance of the cervical spine

Energy Technology Data Exchange (ETDEWEB)

Jirout, J

1980-10-01

The results of dynamic radiographic studies of the cervical spine following isometric exercise of the shoulders and the upper extremities appear to indicate that the commonly seen asymmetries of the joints in the craniocervical and cervicothoracic junction are due to asymmetry in the function of the muscles. The obvious dominance of the muscles on the right side demonstrates the dominance of the left cerebral hemisphere. The clinical importance of this is pointed out.

VCS-SSA Mainz Experiment. Measurement of the beam spin asymmetry in (e polarized p {yields} ep{gamma}) and (e polarized p {yields} ep{pi}{sup 0}). Final analysis - MEMO II

Energy Technology Data Exchange (ETDEWEB)

Fonvieille, H.; Bensafa, I. [LPC-Clermont-Fd, Universite Blaise Pascal, F-63170 Aubiere Cedex (France)

2006-06-15

MEMO-I was written in February 2006 to give details of the second pass analysis of the VCS-SSA experiment. Since then there was our VCS Meeting in March, the production of the PhD thesis by I. Bensafa in May, and complementary studies of the asymmetry which triggered some afterthoughts. Instead of updating MEMO-I which is long enough this memo summarizes these complementary remarks and proposes asymmetry results which are more finalized in view of publication. Various nomenclatures like cuts, variables,etc. have NOT been redefined: please read MEMO-I for that. (authors)

ERP evidence for hemispheric asymmetries in exemplar-specific explicit memory access.

Science.gov (United States)

Küper, Kristina; Zimmer, Hubert D

2015-11-02

The right cerebral hemisphere (RH) appears to be more effective in representing visual objects as distinct exemplars than the left hemisphere (LH) which is presumably biased towards coding objects at the level of abstract prototypes. As of yet, relatively little is known about the role that asymmetries in exemplar-specificity play at the level of explicit memory retrieval. In the present study, we addressed this issue by examining hemispheric asymmetries in the putative event-related potential (ERP) correlates of familiarity (FN400) and recollection (LPC). In an incidental study phase, pictures of familiar objects were presented centrally. At test, participants performed a memory inclusion task on identical repetitions and different exemplars of study items as well as new items which were presented in only one visual hemifield using the divided visual field technique. With respect to familiarity, we observed exemplar-specific FN400 old/new effects that were more pronounced for identical repetitions than different exemplars, irrespective of the hemisphere governing initial stimulus processing. In contrast, LPC old/new effects were subject to some hemispheric asymmetries indicating that exemplar-specific recollection was more extensive in the RH than in the LH. This further corroborates the idea that hemispheric asymmetries should not be generalized but need to be distinguished not only in different domains but also at different levels of processing. Copyright © 2015 Elsevier B.V. All rights reserved.

The effect of unilateral dominance of the cerebral hemispheres on the radiographic appearance of the cervical spine

International Nuclear Information System (INIS)

Jirout, J.

1980-01-01

The results of dynamic radiographic studies of the cervical spine following isometric exercise of the shoulders and the upper extremities appear to indicate that the commonly seen asymmetries of the joints in the craniocervical and cervicothoracic junction are due to asymmetry in the function of the muscles. The obvious dominance of the muscles on the right side demonstrates the dominance of the left cerebral hemisphere. The clinical importance of this is pointed out. (orig.) [de

Usefulness of R2* maps generated by iterative decomposition of water and fat with echo asymmetry and least-squares estimation quantitation sequence for cerebral artery dissection

Energy Technology Data Exchange (ETDEWEB)

Kato, Ayumi; Shinohara, Yuki; Fujii, Shinya; Miyoshi, Fuminori; Kuya, Keita; Ogawa, Toshihide [Tottori University, Division of Radiology, Department of Pathophysiological, and Therapeutic Science, Faculty of Medicine, Yonago (Japan); Yamashita, Eijiro [Tottori University Hospital, Division of Clinical Radiology, Yonago (Japan)

2015-09-15

Acute intramural hematoma resulting from cerebral artery dissection is usually visualized as a region of intermediate signal intensity on T1-weighted images (WI). This often causes problems with distinguishing acute atheromatous lesions from surrounding parenchyma and dissection. The present study aimed to determine whether or not R2* maps generated by the iterative decomposition of water and fat with echo asymmetry and least-squares estimation quantitation sequence (IDEAL IQ) can distinguish cerebral artery dissection more effectively than three-dimensional variable refocusing flip angle TSE T1WI (T1-CUBE) and T2*WI. We reviewed data from nine patients with arterial dissection who were assessed by MR images including R2* maps, T2*WI, T1-CUBE, and 3D time-of-flight (TOF)-MRA. We visually assessed intramural hematomas in each patient as positive (clearly visible susceptibility effect reflecting intramural hematoma as hyperintensity on R2* map and hypointensity on T2*WI), negative (absent intramural hematoma), equivocal (difficult to distinguish between intramural hematoma and other paramagnetic substances such as veins, vessel wall calcification, or hemorrhage) and not evaluable (difficult to determine intramural hematoma due to susceptibility artifacts arising from skull base). Eight of nine patients were assessed during the acute phase. Lesions in all eight patients were positive for intramural hematoma corresponding to dissection sites on R2* maps, while two lesions were positive on T2*WI and three lesions showed high-intensity on T1-CUBE reflected intramural hematoma during the acute phase. R2* maps generated using IDEAL IQ can detect acute intramural hematoma associated with cerebral artery dissection more effectively than T2*WI and earlier than T1-CUBE. (orig.)

Posed versus spontaneous facial expressions are modulated by opposite cerebral hemispheres.

Science.gov (United States)

Ross, Elliott D; Pulusu, Vinay K

2013-05-01

Clinical research has indicated that the left face is more expressive than the right face, suggesting that modulation of facial expressions is lateralized to the right hemisphere. The findings, however, are controversial because the results explain, on average, approximately 4% of the data variance. Using high-speed videography, we sought to determine if movement-onset asymmetry was a more powerful research paradigm than terminal movement asymmetry. The results were very robust, explaining up to 70% of the data variance. Posed expressions began overwhelmingly on the right face whereas spontaneous expressions began overwhelmingly on the left face. This dichotomy was most robust for upper facial expressions. In addition, movement-onset asymmetries did not predict terminal movement asymmetries, which were not significantly lateralized. The results support recent neuroanatomic observations that upper versus lower facial movements have different forebrain motor representations and recent behavioral constructs that posed versus spontaneous facial expressions are modulated preferentially by opposite cerebral hemispheres and that spontaneous facial expressions are graded rather than non-graded movements. Published by Elsevier Ltd.

Speech processing: from peripheral to hemispheric asymmetry of the auditory system.

Science.gov (United States)

Lazard, Diane S; Collette, Jean-Louis; Perrot, Xavier

2012-01-01

Language processing from the cochlea to auditory association cortices shows side-dependent specificities with an apparent left hemispheric dominance. The aim of this article was to propose to nonspeech specialists a didactic review of two complementary theories about hemispheric asymmetry in speech processing. Starting from anatomico-physiological and clinical observations of auditory asymmetry and interhemispheric connections, this review then exposes behavioral (dichotic listening paradigm) as well as functional (functional magnetic resonance imaging and positron emission tomography) experiments that assessed hemispheric specialization for speech processing. Even though speech at an early phonological level is regarded as being processed bilaterally, a left-hemispheric dominance exists for higher-level processing. This asymmetry may arise from a segregation of the speech signal, broken apart within nonprimary auditory areas in two distinct temporal integration windows--a fast one on the left and a slower one on the right--modeled through the asymmetric sampling in time theory or a spectro-temporal trade-off, with a higher temporal resolution in the left hemisphere and a higher spectral resolution in the right hemisphere, modeled through the spectral/temporal resolution trade-off theory. Both theories deal with the concept that lower-order tuning principles for acoustic signal might drive higher-order organization for speech processing. However, the precise nature, mechanisms, and origin of speech processing asymmetry are still being debated. Finally, an example of hemispheric asymmetry alteration, which has direct clinical implications, is given through the case of auditory aging that mixes peripheral disorder and modifications of central processing. Copyright © 2011 The American Laryngological, Rhinological, and Otological Society, Inc.

Cerebral haemodynamics in female teenagers exposed to ionizing irradiation in low doses and living in 'clean' areas

International Nuclear Information System (INIS)

Naumova, G.I.; Naumov, A.D.

1999-01-01

Thirty seven girls living in various districts of the Mogilev Region and having received absorbed irradiation dose at thyroid gland owing to iodine 131 more than 1 Gy and 65 ones living in relatively free from radionuclide areas were examined. The results indicated changes in cerebral haemodynamics in the first group. Vegetative vessels dystonia syntrom had been revealed at 31 exposed to iodine 131 irradiation patients (83%) and at 16 patients (25%) from the control group. The changes tended to induce hypotonia of small cerebral peripheral blood vessels with indices asymmetry of left and right cerebral hemispheres

Statistical parametric mapping of Tc-99m HMPAO SPECT cerebral perfusion in the normal elderly

International Nuclear Information System (INIS)

Turlakow, A.; Scott, A.M.; Berlangieri, S.U.; Sonkila, C.; Wardill, T.D.; Crowley, K.; Abbott, D.; Egan, G.F.; McKay, W.J.; Hughes, A.

1998-01-01

Full text: The clinical value of Tc-99m HMPAO SPECT cerebral blood flow studies in cognitive and neuropsychiatric disorders has been well described. Currently, interpretation of these studies relies on qualitative or semi- quantitative techniques. The aim of our study is to generate statistical measures of regional cerebral perfusion in the normal elderly using statistical parametric mapping (Friston et al, Wellcome Department of Cognitive Neurology, London, UK) in order to facilitate the objective analysis of cerebral blood flow studies in patient groups. A cohort of 20 healthy, elderly volunteers, aged 68 to 81 years, was prospectively selected on the basis of normal physical examination and neuropsychological testing. Subjects with risk factors, or a history of cognitive impairment were excluded from our study group. All volunteers underwent SPECT cerebral blood flow imaging, 30 minutes following the administration of 370 MBq Tc-99m HMPAO, on a Trionix Triad XLT triple-headed scanner (Trionix Research Laboratory Twinsburg, OH) using high resolution, fan-beam collimators resulting in a system resolution of 10 mm full width at half-maximum (FWHM). The SPECT cerebral blood flow studies were analysed using statistical parametric mapping (SPM) software specifically developed for the routine statistical analysis of functional neuroimaging data. The SPECT images were coregistered with each individual's T1-weighted MR volume brain scan and spatially normalized to standardised Talairach space. Using SPM, these data were analyzed for differences in interhemispheric regional cerebral blood flow. Significant asymmetry of cerebral perfusion was detected in the pre-central gyrus at the 95th percentile. In conclusion, the interpretation of cerebral blood flow studies in the elderly should take into account the statistically significant asymmetry in interhemispheric pre-central cortical blood flow. In the future, clinical studies will be compared to statistical data sets in age

Statistical parametric mapping of Tc-99m HMPAO SPECT cerebral perfusion in the normal elderly

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Turlakow, A.; Scott, A.M.; Berlangieri, S.U.; Sonkila, C.; Wardill, T.D.; Crowley, K.; Abbott, D.; Egan, G.F.; McKay, W.J.; Hughes, A. [Austin and Repatriation Medical Centre, Heidelberg, VIC (Australia). Departments of Nuclear Medicine and Centre for PET Neurology and Clinical Neuropsychology

1998-06-01

Full text: The clinical value of Tc-99m HMPAO SPECT cerebral blood flow studies in cognitive and neuropsychiatric disorders has been well described. Currently, interpretation of these studies relies on qualitative or semi- quantitative techniques. The aim of our study is to generate statistical measures of regional cerebral perfusion in the normal elderly using statistical parametric mapping (Friston et al, Wellcome Department of Cognitive Neurology, London, UK) in order to facilitate the objective analysis of cerebral blood flow studies in patient groups. A cohort of 20 healthy, elderly volunteers, aged 68 to 81 years, was prospectively selected on the basis of normal physical examination and neuropsychological testing. Subjects with risk factors, or a history of cognitive impairment were excluded from our study group. All volunteers underwent SPECT cerebral blood flow imaging, 30 minutes following the administration of 370 MBq Tc-99m HMPAO, on a Trionix Triad XLT triple-headed scanner (Trionix Research Laboratory Twinsburg, OH) using high resolution, fan-beam collimators resulting in a system resolution of 10 mm full width at half-maximum (FWHM). The SPECT cerebral blood flow studies were analysed using statistical parametric mapping (SPM) software specifically developed for the routine statistical analysis of functional neuroimaging data. The SPECT images were coregistered with each individual`s T1-weighted MR volume brain scan and spatially normalized to standardised Talairach space. Using SPM, these data were analyzed for differences in interhemispheric regional cerebral blood flow. Significant asymmetry of cerebral perfusion was detected in the pre-central gyrus at the 95th percentile. In conclusion, the interpretation of cerebral blood flow studies in the elderly should take into account the statistically significant asymmetry in interhemispheric pre-central cortical blood flow. In the future, clinical studies will be compared to statistical data sets in age

The effect of combined treatment with transcranial direct current stimulation on cerebral blood flow in patients with cerebral palsy

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K. V. Yatsenko

2017-02-01

Full Text Available There is a close link between the activity of the brain and cerebral blood supply. Transcranial direct current stimulation (tDCS modulates the activity of the cerebral cortex and thus affects the cerebral blood flow. The aim of the study was to investigate the effect of combined treatment with tDCS on cerebral blood flow in patients with cerebral palsy (CP. Materials and Methods. 60 patients with various forms of cerebral palsy were examined and received the course of treatment. The comparison group was formed from 30 children who received the course of basic medical and rehabilitation procedures. The main group included 30 children who, in addition to the same therapy, received a course of tDCS. A transcranial Doppler ultrasound examination of head blood vessels was used for the study of cerebral hemodynamics in children with cerebral palsy before and after combined treatment with tDCS. Results. tDCS reduced asymmetry coefficient of blood flow velocity in the middle cerebral arteries (MCA by 12.3 %, whereas in the comparison group only by 2.5 %; in the anterior cerebral artery (ACA – 9.5 %, while in the comparison group – 0.8 %. tDCS significantly reduced the high mean blood flow velocity per cycle (MFV in the basilar artery (BA, MCA and ACA (21.7 %, 18.3 % and 7.8 %, respectively; in the comparison group no statistically significant positive dynamics was observed. tDCS significantly increased the low MVF in the BA, MCA and ACA (29.7 %, 21.2 % and 9.7 % respectively; a statistically significant increase of MVF by 9.9 % was only in the CMA in the comparison group of patients. Conclusions. Our data indicate that the use of tDCS in the combined treatment of CP patients improves cerebral hemodynamics in 87 % of patients, in contrast to 52 % in the comparison group. The addition of transcranial direct current stimulation method to the complex treatment of patients with cerebral palsy improves the effectiveness of treatment and may also

Is complementary and alternative therapy effective for women in the climacteric period?

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Kim, Mi Young; Choi, Seung Do; Ryu, Aeli

2015-04-01

Vasomotor symptoms start about 2 years prior to menopause in women who are approaching menopause, and early menopause symptoms appear including emotional disturbance and anxiety, followed by physical changes such as vaginal dryness, urinary incontinence and skin wrinkles. As time progresses, osteoporosis, cardiovascular diseases, and dementia occur consecutively. Hormone therapy is primarily considered for the relief of menopause symptoms in postmenopausal women. However, as hormone replacement has emerged as a therapy that increases the potential risk of thrombosis, cerebral infarction and breast cancer, complementary and alternative medicine has drawn much attention. This study aimed to examine the types and effects of evidence-based complementary and alternative therapies that are currently used.

Nasopupillary asymmetry.

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Arenas, Eduardo; Muñoz, Diana; Matheus, Evelyn; Morales, Diana

2014-01-01

To establish the prevalence of nasopupillary asymmetry (difference in nasopupillary distances) in the population and its relation with the interpupillary distance. A retrospective descriptive study was conducted by reviewing of 1262 medical records. The values of nasopupillary asymmetry and the interpupillary distance were obtained. A statistical analysis was made and the correlation between these variables was established. Seventy-nine percent of the population presented some degree of nasopupillary asymmetry. The interpupillary distance had a very low correlation with the nasopupillary asymmetry (r = 0.074, P = 0.0). It is advisable to use the nasopupillary distance of each eye as a standard measurement.

Dyke-Davidoff-Masson syndrome: case report of fetal unilateral ventriculomegaly and hypoplastic left middle cerebral artery.

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Piro, Ettore; Piccione, Maria; Marrone, Gianluca; Giuffrè, Mario; Corsello, Giovanni

2013-05-14

Prenatal ultrasonographic detection of unilateral cerebral ventriculomegaly arises suspicion of pathological condition related to cerebrospinal fluid flow obstruction or cerebral parenchimal pathology. Dyke-Davidoff-Masson syndrome is a rare condition characterized by cerebral hemiatrophy, calvarial thickening, skull and facial asymmetry, contralateral hemiparesis, cognitive impairment and seizures. Congenital and acquired types are recognized and have been described, mainly in late childhood, adolescence and adult ages. We describe a female infant with prenatal diagnosis of unilateral left ventriculomegaly in which early brain MRI and contrast enhanced-MRI angiography, showed cerebral left hemiatrophy associated with reduced caliber of the left middle cerebral artery revealing the characteristic findings of the Dyke-Davidoff-Masson syndrome. Prenatal imaging, cerebral vascular anomaly responsible for the cerebral hemiatrophy and the early clinical evolution have never been described before in such a young child and complete the acquired clinical descriptions in older children. Differential diagnosis, genetic investigations, neurophysiologic assessments, short term clinical and developmental follow up are described. Dyke-Davidoff-Masson syndrome must be ruled out in differential diagnosis of fetal unilateral ventriculomegaly. Early clinical assessment, differential diagnosis and cerebral imaging including cerebral MRI angiography allow the clinicians to diagnose also in early infancy this rare condition.

The association between hemispheric specialization for language production and for spatial attention depends on left-hand preference strength.

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Zago, Laure; Petit, Laurent; Mellet, Emmanuel; Jobard, Gaël; Crivello, Fabrice; Joliot, Marc; Mazoyer, Bernard; Tzourio-Mazoyer, Nathalie

2016-12-01

Cerebral lateralization for language production and spatial attention and their relationships with manual preference strength (MPS) were assessed in a sample of 293 healthy volunteers, including 151 left-handers, using fMRI during covert sentence production (PROD) and line bisection judgment (LBJ) tasks, as compared to high- and low-level reference tasks. At the group level, we found the expected complementary hemispheric specialization (HS) with leftward asymmetries for PROD within frontal and temporal regions and rightward asymmetries for LBJ within frontal and posterior occipito-parieto-temporal regions. Individual hemispheric (HLI) and regional (frontal and occipital) lateralization indices (LI) were then calculated on the activation maps for PROD and LBJ. We found a correlation between the degree of rightward cerebral asymmetry and the leftward behavioral attentional bias recorded during LBJ task. This correlation was found when LBJ-LI was computed over the hemispheres, in the frontal lobes, but not in the occipital lobes. We then investigated whether language production and spatial attention cerebral lateralization relate to each other, and whether manual preference was a variable that impacted the complementary HS of these functions. No correlation was found between spatial and language LIs in the majority of our sample of participants, including right-handers with a strong right-hand preference (sRH, n=97) and mixed-handers (MH, n=97), indicating that these functions lateralized independently. By contrast, in the group of left-handers with a strong left-hand preference (sLH, n= 99), a negative correlation was found between language and spatial lateralization. This negative correlation was found when LBJ-LI and PROD-LI were computed over the hemispheres, in the frontal lobes and between the occipital lobes for LBJ and the frontal lobes for PROD. These findings underline the importance to include sLH in the study sample to reveal the underlying mechanisms of

Local fibrinolytic therapy for patients with cerebral embolism and reversibility of cerebral ischemia in ultra-acute stage

International Nuclear Information System (INIS)

Koizumi, Takayuki

1993-01-01

The present study was undertaken to determine candidates for fibrinolytic therapy in cerebral embolism. Forty-three patients were examined by single photon emission computed tomography (SPECT) using 99m c-d, hexamethyl-propylene-amine oxime (HM-PAO) or N-isopropyl p[ 123 I]-iodoamphetamine ( 123 I-IMP) just before and after intra-arterial local fibrinolytic therapy. Regional cerebellar ratio (R/Ce) and asymmetry index (AI) were calculated just before the treatment (n=9). Quantitative analysis was performed after the treatment (n=all). SPECT images taken within 24 hours after the treatment fell into three patters: normal perfusion, hypoperfusion, and hyperperfusion. Patients showing normal perfusion pattern after complete recanalization developed no or smaller infarction on CT scans. However, patients showing either hypoperfusion or hyperperfusion developed large infarction. Regions with R/Ce ratio of 0.3 or smaller and/or AI of 1.5 or greater were irreversible, which was associated with cerebral infarction regardless of the duration of ischemia. On the other hand, regions with R/Ce of 0.5 or greater or AI of 1.2 or smaller were reversible with no association of infarction. Intra-arterial local fibrinolytic therapy seems to be helpful for patients with slight reduction of regional cerebral blood flow (i.e., R/Ce>0.5, AI 1.5). These findings indicate that SPECT is capable of determining reversibility of ischemic region, thereby contributing to better management of patients with acute cerebral embolism. (N.K.)

Gender and age effects in structural brain asymmetry as measured by MRI texture analysis.

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Kovalev, Vassili A; Kruggel, Frithjof; von Cramon, D Yves

2003-07-01

Effects of gender and age on structural brain asymmetry were studied by 3D texture analysis in 380 adults. Asymmetry is detected by comparing the complex 3D gray-scale image patterns in the left and right cerebral hemispheres as revealed by anatomical T1-weighted MRI datasets. The Talairach and Tournoux parcellation system was applied to study the asymmetry on five levels: the whole cerebrum, nine coronal sections, 12 axial sections, boxes resulting from both coronal and axial subdivisions, and by a sliding spherical window of 9 mm diameter. The analysis revealed that the brain asymmetry increases in the anterior-posterior direction starting from the central region onward. Male brains were found to be more asymmetric than female. This gender-related effect is noticeable in all brain areas but is most significant in the superior temporal gyrus, Heschl's gyrus, the adjacent white matter regions in the temporal stem and the knee of the optic radiation, the thalamus, and the posterior cingulate. The brain asymmetry increases significantly with age in the inferior frontal gyrus, anterior insula, anterior cingulate, parahippocampal gyrus, retrosplenial cortex, coronal radiata, and knee region of the internal capsule. Asymmetry decreases with age in the optic radiation, precentral gyrus, and angular gyrus. The texture-based method reported here is based on extended multisort cooccurrence matrices that employ intensity, gradient, and anisotropy features in a uniform way. It is sensitive, simple to reproduce, robust, and unbiased in the sense that segmentation of brain compartments and spatial transformations are not necessary. Thus, it should be considered as another tool for digital morphometry in neuroscience.

Strand bias in complementary single-nucleotide polymorphisms of transcribed human sequences: evidence for functional effects of synonymous polymorphisms

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Majewski Jacek

2006-08-01

Full Text Available Abstract Background Complementary single-nucleotide polymorphisms (SNPs may not be distributed equally between two DNA strands if the strands are functionally distinct, such as in transcribed genes. In introns, an excess of A↔G over the complementary C↔T substitutions had previously been found and attributed to transcription-coupled repair (TCR, demonstrating the valuable functional clues that can be obtained by studying such asymmetry. Here we studied asymmetry of human synonymous SNPs (sSNPs in the fourfold degenerate (FFD sites as compared to intronic SNPs (iSNPs. Results The identities of the ancestral bases and the direction of mutations were inferred from human-chimpanzee genomic alignment. After correction for background nucleotide composition, excess of A→G over the complementary T→C polymorphisms, which was observed previously and can be explained by TCR, was confirmed in FFD SNPs and iSNPs. However, when SNPs were separately examined according to whether they mapped to a CpG dinucleotide or not, an excess of C→T over G→A polymorphisms was found in non-CpG site FFD SNPs but was absent from iSNPs and CpG site FFD SNPs. Conclusion The genome-wide discrepancy of human FFD SNPs provides novel evidence for widespread selective pressure due to functional effects of sSNPs. The similar asymmetry pattern of FFD SNPs and iSNPs that map to a CpG can be explained by transcription-coupled mechanisms, including TCR and transcription-coupled mutation. Because of the hypermutability of CpG sites, more CpG site FFD SNPs are relatively younger and have confronted less selection effect than non-CpG FFD SNPs, which can explain the asymmetric discrepancy of CpG site FFD SNPs vs. non-CpG site FFD SNPs.

Selected Gray Matter Volumes and Gender but Not Basal Ganglia nor Cerebellum Gyri Discriminate Left Versus Right Cerebral Hemispheres: Multivariate Analyses in human Brains at 3T.

Science.gov (United States)

Roldan-Valadez, Ernesto; Suarez-May, Marcela A; Favila, Rafael; Aguilar-Castañeda, Erika; Rios, Camilo

2015-07-01

Interest in the lateralization of the human brain is evident through a multidisciplinary number of scientific studies. Understanding volumetric brain asymmetries allows the distinction between normal development stages and behavior, as well as brain diseases. We aimed to evaluate volumetric asymmetries in order to select the best gyri able to classify right- versus left cerebral hemispheres. A cross-sectional study performed in 47 right-handed young-adults healthy volunteers. SPM-based software performed brain segmentation, automatic labeling and volumetric analyses for 54 regions involving the cerebral lobes, basal ganglia and cerebellum from each cerebral hemisphere. Multivariate discriminant analysis (DA) allowed the assembling of a predictive model. DA revealed one discriminant function that significantly differentiated left vs. right cerebral hemispheres: Wilks' λ = 0.008, χ(2) (9) = 238.837, P brain gyri are able to accurately classify left vs. right cerebral hemispheres by using a multivariate approach; the selected regions correspond to key brain areas involved in attention, internal thought, vision and language; our findings favored the concept that lateralization has been evolutionary favored by mental processes increasing cognitive efficiency and brain capacity. © 2015 Wiley Periodicals, Inc.

Regional quantitative noninvasive assessment of cerebral perfusion and function with N-Isopropyl-[123I]p-iodoamphetamine

International Nuclear Information System (INIS)

von Schulthess, G.K.; Ketz, E.; Schubiger, P.A.; Bekier, A.

1985-01-01

Although several reports on the clinical usefulness of N-isopropyl-[ 123 I]p-iodoamphetamine (IMP) in the diagnosis of cerebral disease have appeared in the literature, quantitative, noninvasive measurements of regional cerebral blood flow with this method pose difficulties because cerebral IMP uptake not only depends on cerebral perfusion but also on cerebral function. Rather than trying to develop a method to measure cerebral perfusion with IMP, the authors have chosen to test a method to quantitatively evaluate planar and emission computed tomographic (ECT) studies by comparing the data obtained in patients with established pathology with the data obtained in a group of normal individuals. Using this method, absolute cerebral IMP uptake (counts/pixel/mCi/min) and planar anterior right-left ratios were obtained. Also measured were right-left ratios obtained from 12 paired regions in three ECT slices. The evaluation of the patients cerebral IMP uptake asymmetries relative to the normal standard values is a useful adjunct to qualitative image analysis in assessing the presence ans severity of disease, as qualitative analysis is prone to false-positive and negative results. Cerebral IMP uptake as measured in cts/pixel/mCi/min is abnormal only in severe cerebral disease and therefore generally a less helpful parameter

Cerebral glucose metabolism in Wernicke's, Broca's, and conduction aphasia

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Metter, E.J.; Kempler, D.; Jackson, C.; Hanson, W.R.; Mazziotta, J.C.; Phelps, M.E.

1989-01-01

Cerebral glucose metabolism was evaluated in patients with either Wernicke's (N = 7), Broca's (N = 11), or conduction (N = 10) aphasia using /sup 18/F-2-fluoro-2-deoxy-D-glucose with positron emission tomography. The three aphasic syndromes differed in the degree of left-to-right frontal metabolic asymmetry, with Broca's aphasia showing severe asymmetry and Wernicke's aphasia mild-to-moderate metabolic asymmetry, while patients with conduction aphasia were metabolically symmetric. On the other hand, the three syndromes showed the same degree of metabolic decline in the left temporal region. The parietal region appeared to separate conduction aphasia from both Broca's and Wernicke's aphasias. Common aphasic features in the three syndromes appear to be due to common changes in the temporal region, while unique features were associated with frontal and parietal metabolic differences.

Computer tomography of the brain and spectrophotometry of the CSF in cerebral concussion and contusion

International Nuclear Information System (INIS)

Bergvall, U.; Kjellin, K.G.; Levander, B.; Svendsen, P.; Soederstroem, C.E.

1978-01-01

Computer tomography (CT) and spectrophotometry of CSF were performed in 30 patients with the clinical diagnosis of cerebral concussion or contusion. The patients with concussion all had normal CT-findings. Spectrophotometry of CSF was sometimes positive for cerebral contusion with normal CT-findings, but the two methods were complementary so that the extent of the lesion was determined by CT and spectrophotometry of CSF indicated the cause. (Auth.)

Topographic brain mapping of emotion-related hemisphere asymmetries.

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Roschmann, R; Wittling, W

1992-03-01

The study used topographic brain mapping of visual evoked potentials to investigate emotion-related hemisphere asymmetries. The stimulus material consisted of color photographs of human faces, grouped into two emotion-related categories: normal faces (neutral stimuli) and faces deformed by dermatological diseases (emotional stimuli). The pictures were presented tachistoscopically to 20 adult right-handed subjects. Brain activity was recorded by 30 EEG electrodes with linked ears as reference. The waveforms were averaged separately with respect to each of the two stimulus conditions. Statistical analysis by means of significance probability mapping revealed significant differences between stimulus conditions for two periods of time, indicating right hemisphere superiority in emotion-related processing. The results are discussed in terms of a 2-stage-model of emotional processing in the cerebral hemispheres.

The potential role of brain asymmetry in the development of adolescent idiopathic scoliosis: a hypothesis.

Science.gov (United States)

Niesluchowski, W; Dabrowska, A; Kedzior, K; Zagrajek, T

1999-10-01

The size asymmetry of cerebral hemispheres may predispose to head tilt and asymmetric blocking of the zygapophysial joints, potentially leading to the development of compensatory curvatures in the lower segments of the spine. To analyze the effects of spinal manipulation, maintained by an exercise program, on the progression of idiopathic adolescent scoliosis in 2 children aged 6 and 10. The scoliosis found was 16 and 60 degrees. For diagnosis and monitoring of therapy, we recorded qualitative parameters of shoulder asymmetry, axillary line asymmetry, and scapular angle position. Manual treatment consisted of the examinations of all sliding motion in zygapophysial joints and both sacroiliac joints and removing the limitations of the sliding motions according to the method of Karel Lewit. The treatment procedure consisted of 3 or 4 manipulations within 17 months and an exercise program. The manipulation effects were maintained by the exercise program. The exercises were done in 2 or 3 sessions weekly for a year. In both patients we observed that scoliosis decompensation was successfully stopped and the effects of the correction persisted for 10 years. Brain and head asymmetry may be only a transient state, predisposing to asymmetric blocking at the atlanto-occipital level. Removal of blocking may prevent curve progression in children who had adolescent idiopathic scoliosis. The manipulative therapy may also have a promising effect on retarding curve progression when used in skeletally immature patient.

Assessment of arcuate fasciculus with diffusion-tensor tractography may predict the prognosis of aphasia in patients with left middle cerebral artery infarcts

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Hosomi, Akiko; Nagakane, Yoshinari; Kuriyama, Nagato; Mizuno, Toshiki; Nakagawa, Masanori [Kyoto Prefectural University of Medicine, Department of Neurology, Graduate School of Medical Science, Kyoto (Japan); Yamada, Kei; Nishimura, Tsunehiko [Kyoto Prefectural University of Medicine, Department of Radiology, Graduate School of Medical Science, Kyoto (Japan)

2009-09-15

It is often clinically difficult to assess the severity of aphasia in the earliest stage of cerebral infarction. A method enabling objective assessment of verbal function is needed for this purpose. We examined whether diffusion tensor (DT) tractography is of clinical value in assessing aphasia. Thirteen right-handed patients with left middle cerebral artery infarcts who were scanned within 2 days after stroke onset were enrolled in this study. Magnetic resonance data of ten control subjects were also examined by DT tractography. Based on the severity of aphasia at discharge, patients were divided into two groups: six patients in the aphasic group and seven in the nonaphasic group. Fractional anisotropy (FA) and number of arcuate fasciculus fibers were evaluated. Asymmetry index was calculated for both FA and number of fibers. FA values for the arcuate fasciculus fibers did not differ between hemispheres in either the patient groups or the controls. Number of arcuate fasciculus fibers exhibited a significant leftward asymmetry in the controls and the nonaphasic group but not in the aphasic group. Asymmetry index of number of fibers was significantly lower (rightward) in the aphasic group than in the nonaphasic (P = 0.015) and control (P = 0.005) groups. Loss of leftward asymmetry in number of AF fibers predicted aphasia at discharge with a sensitivity of 0.83 and specificity of 0.86. Asymmetry of arcuate fasciculus fibers by DT tractography may deserve to be assessed in acute infarction for predicting the fate of vascular aphasia. (orig.)

Assessment of arcuate fasciculus with diffusion-tensor tractography may predict the prognosis of aphasia in patients with left middle cerebral artery infarcts

International Nuclear Information System (INIS)

Hosomi, Akiko; Nagakane, Yoshinari; Kuriyama, Nagato; Mizuno, Toshiki; Nakagawa, Masanori; Yamada, Kei; Nishimura, Tsunehiko

2009-01-01

It is often clinically difficult to assess the severity of aphasia in the earliest stage of cerebral infarction. A method enabling objective assessment of verbal function is needed for this purpose. We examined whether diffusion tensor (DT) tractography is of clinical value in assessing aphasia. Thirteen right-handed patients with left middle cerebral artery infarcts who were scanned within 2 days after stroke onset were enrolled in this study. Magnetic resonance data of ten control subjects were also examined by DT tractography. Based on the severity of aphasia at discharge, patients were divided into two groups: six patients in the aphasic group and seven in the nonaphasic group. Fractional anisotropy (FA) and number of arcuate fasciculus fibers were evaluated. Asymmetry index was calculated for both FA and number of fibers. FA values for the arcuate fasciculus fibers did not differ between hemispheres in either the patient groups or the controls. Number of arcuate fasciculus fibers exhibited a significant leftward asymmetry in the controls and the nonaphasic group but not in the aphasic group. Asymmetry index of number of fibers was significantly lower (rightward) in the aphasic group than in the nonaphasic (P = 0.015) and control (P = 0.005) groups. Loss of leftward asymmetry in number of AF fibers predicted aphasia at discharge with a sensitivity of 0.83 and specificity of 0.86. Asymmetry of arcuate fasciculus fibers by DT tractography may deserve to be assessed in acute infarction for predicting the fate of vascular aphasia. (orig.)

Experimental investigation of transverse spin asymmetries in muon-p SIDIS processes: Sivers asymmetries

CERN Document Server

Adolph, C.; Alexakhin, V.Yu.; Alexandrov, Yu.; Alexeev, G.D.; Amoroso, A.; Antonov, A.A.; Austregesilo, A.; Badelek, B.; Balestra, F.; Barth, J.; Baum, G.; Bedfer, Y.; Bernhard, J.; Bertini, R.; Bettinelli, M.; Bicker, K.; Bieling, J.; Birsa, R.; Bisplinghoff, J.; Bordalo, P.; Bradamante, F.; Braun, C.; Bravar, A.; Bressan, A.; Burtin, E.; Capozza, L.; Chiosso, M.; Chung, S.U.; Cicuttin, A.; Crespo, M.L.; Dalla Torre, S.; Das, S.; Dasgupta, S.S.; Dasgupta, S.; Denisov, O.Yu.; Dhara, L.; Donskov, S.V.; Doshita, N.; Duic, V.; Dunnweber, W.; Dziewiecki, M.; Efremov, A.; Elia, C.; Eversheim, P.D.; Eyrich, W.; Faessler, M.; Ferrero, A.; Filin, A.; Finger, M.; Fischer, H.; Franco, C.; von Hohenesche, N.du Fresne; Friedrich, J.M.; Frolov, V.; Garfagnini, R.; Gautheron, F.; Gavrichtchouk, O.P.; Gerassimov, S.; Geyer, R.; Giorgi, M.; Gnesi, I.; Gobbo, B.; Goertz, S.; Grabmuller, S.; Grasso, A.; Grube, B.; Gushterski, R.; Guskov, A.; Guthorl, T.; Haas, F.; von Harrach, D.; Heinsius, F.H.; Herrmann, F.; Hess, C.; Hinterberger, F.; Horikawa, N.; Hoppner, Ch.; d'Hose, N.; Ishimoto, S.; Ivanov, O.; Ivanshin, Yu.; Iwata, T.; Jahn, R.; Jary, V.; Jasinski, P.; Joosten, R.; Kabuss, E.; Kang, D.; Ketzer, B.; Khaustov, G.V.; Khokhlov, Yu.A.; Kisselev, Yu.; Klein, F.; Klimaszewski, K.; Koblitz, S.; Koivuniemi, J.H.; Kolosov, V.N.; Kondo, K.; Konigsmann, K.; Konorov, I.; Konstantinov, V.F.; Korzenev, A.; Kotzinian, A.M.; Kouznetsov, O.; Kramer, M.; Kroumchtein, Z.V.; Kunne, F.; Kurek, K.; Lauser, L.; Lednev, A.A.; Lehmann, A.; Levorato, S.; Lichtenstadt, J.; Liska, T.; Maggiora, A.; Magnon, A.; Makke, N.; Mallot, G.K.; Mann, A.; Marchand, C.; Martin, A.; Marzec, J.; Matsuda, T.; Meshcheryakov, G.; Meyer, W.; Michigami, T.; Mikhailov, Yu.V.; Moinester, M.A.; Morreale, A.; Mutter, A.; Nagaytsev, A.; Nagel, T.; Negrini, T.; Nerling, F.; Neubert, S.; Neyret, D.; Nikolaenko, V.I.; Nowak, W.D.; Nunes, A.S.; Olshevsky, A.G.; Ostrick, M.; Padee, A.; Panknin, R.; Panzieri, D.; Parsamyan, B.; Paul, S.; Perevalova, E.; Pesaro, G.; Peshekhonov, D.V.; Piragino, G.; Platchkov, S.; Pochodzalla, J.; Polak, J.; Polyakov, V.A.; Pretz, J.; Quaresma, M.; Quintans, C.; Rajotte, J.F.; Ramos, S.; Rapatsky, V.; Reicherz, G.; Richter, A.; Rocco, E.; Rondio, E.; Rossiyskaya, N.S.; Ryabchikov, D.I.; Samoylenko, V.D.; Sandacz, A.; Sapozhnikov, M.G.; Sarkar, S.; Savin, I.A.; Sbrizzai, G.; Schiavon, P.; Schill, C.; Schluter, T.; Schmidt, K.; Schmitt, L.; Schonning, K.; Schopferer, S.; Schott, M.; Schroder, W.; Shevchenko, O.Yu.; Silva, L.; Sinha, L.; Sissakian, A.N.; Slunecka, M.; Smirnov, G.I.; Sosio, S.; Sozzi, F.; Srnka, A.; Steiger, L.; Stolarski, M.; Sulc, M.; Sulej, R.; Suzuki, H.; Sznajder, P.; Takekawa, S.; Wolbeek, J.Ter; Tessaro, S.; Tessarotto, F.; Tkatchev, L.G.; Uhl, S.; Uman, I.; Vandenbroucke, M.; Virius, M.; Vlassov, N.V.; Wang, L.; Wilfert, M.; Windmolders, R.; Wislicki, W.; Wollny, H.; Zaremba, K.; Zavertyaev, M.; Zemlyanichkina, E.; Ziembicki, M.; Zhuravlev, N.; Zvyagin, A.

2012-10-31

The COMPASS Collaboration at CERN has measured the transverse spin azimuthal asymmetry of charged hadrons produced in semi-inclusive deep inelastic scattering using a 160 GeV positive muon beam and a transversely polarised NH_3 target. The Sivers asymmetry of the proton has been extracted in the Bjorken x range 0.003 0.03. The asymmetry is different from zero and positive also in the low x region, where sea-quarks dominate. The kinematic dependence of the asymmetry has also been investigated and results are given for various intervals of hadron and virtual photon fractional energy. In contrast to the case of the Collins asymmetry, the results on the Sivers asymmetry suggest a strong dependence on the four-momentum transfer to the nucleon, in agreement with the most recent calculations.

Cerebello-cerebral functional relationship in spinocerebellar degeneration using positron emission tomography

International Nuclear Information System (INIS)

Koshi, Yasuhiko; Kitamura, Shin; Sakayori, Osamu; Komaba, Yuichi; Terashi, Akiro

1995-01-01

In order to investigate the laterality of cerebellar ataxia and its influence for the cerebral cortex in spinocerebellar degeneration (SCD), regional cerebral blood flow (rCBF) was measured using positron emission tomography (PET) in 10 patients with sporadic olivopontocerebellar atrophy (sOPCA), 7 patients with hereditary SCD (hSCD), and 10 age matched control subjects. The laterality of cerebellar ataxia was evaluated by the total score of the difference between left and right limbs of three limb-coordination tests. The lateralities of rCBF were calculated by asymmetry indices (AIs) of each region of interest in the cerebellum, thalamus, caudate, putamen, cerebral cortices. The laterality of cerebellar ataxia was significantly correlated with AI in the cerebellum in patients with sOPCA. Furthermore, significant negative correlations were observed between AI in the cerebellum and each AI in the thalamus, frontal cortex in patients with sOPCA. However, no correlations were observed between AI in the cerebellum and the other AIs in controls and patients with h SCD. Duration of illness in patients with sOPCA with laterality is shorter than that in patients without laterality. These results suggest that the existence of crossed cerebello-cerebral diaschisis (CCCD) resulting from transneuronal deactivation through cerebello-thalamo-cerebral pathway in patients with the early stage of sOPCA with laterality. (author)

Cerebello-cerebral functional relationship in spinocerebellar degeneration using positron emission tomography

Energy Technology Data Exchange (ETDEWEB)

Koshi, Yasuhiko; Kitamura, Shin; Sakayori, Osamu; Komaba, Yuichi; Terashi, Akiro [Nippon Medical School, Tokyo (Japan)

1995-07-01

In order to investigate the laterality of cerebellar ataxia and its influence for the cerebral cortex in spinocerebellar degeneration (SCD), regional cerebral blood flow (rCBF) was measured using positron emission tomography (PET) in 10 patients with sporadic olivopontocerebellar atrophy (sOPCA), 7 patients with hereditary SCD (hSCD), and 10 age matched control subjects. The laterality of cerebellar ataxia was evaluated by the total score of the difference between left and right limbs of three limb-coordination tests. The lateralities of rCBF were calculated by asymmetry indices (AIs) of each region of interest in the cerebellum, thalamus, caudate, putamen, cerebral cortices. The laterality of cerebellar ataxia was significantly correlated with AI in the cerebellum in patients with sOPCA. Furthermore, significant negative correlations were observed between AI in the cerebellum and each AI in the thalamus, frontal cortex in patients with sOPCA. However, no correlations were observed between AI in the cerebellum and the other AIs in controls and patients with h SCD. Duration of illness in patients with sOPCA with laterality is shorter than that in patients without laterality. These results suggest that the existence of crossed cerebello-cerebral diaschisis (CCCD) resulting from transneuronal deactivation through cerebello-thalamo-cerebral pathway in patients with the early stage of sOPCA with laterality. (author).

Spatiotemporal Fractionation Schemes for Irradiating Large Cerebral Arteriovenous Malformations

Energy Technology Data Exchange (ETDEWEB)

Unkelbach, Jan, E-mail: junkelbach@mgh.harvard.edu [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Bussière, Marc R. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Chapman, Paul H. [Department of Neurosurgery, Massachusetts General Hospital, Boston, Massachusetts (United States); Loeffler, Jay S.; Shih, Helen A. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States)

2016-07-01

Purpose: To optimally exploit fractionation effects in the context of radiosurgery treatments of large cerebral arteriovenous malformations (AVMs). In current practice, fractionated treatments divide the dose evenly into several fractions, which generally leads to low obliteration rates. In this work, we investigate the potential benefit of delivering distinct dose distributions in different fractions. Methods and Materials: Five patients with large cerebral AVMs were reviewed and replanned for intensity modulated arc therapy delivered with conventional photon beams. Treatment plans allowing for different dose distributions in all fractions were obtained by performing treatment plan optimization based on the cumulative biologically effective dose delivered at the end of treatment. Results: We show that distinct treatment plans can be designed for different fractions, such that high single-fraction doses are delivered to complementary parts of the AVM. All plans create a similar dose bath in the surrounding normal brain and thereby exploit the fractionation effect. This partial hypofractionation in the AVM along with fractionation in normal brain achieves a net improvement of the therapeutic ratio. We show that a biological dose reduction of approximately 10% in the healthy brain can be achieved compared with reference treatment schedules that deliver the same dose distribution in all fractions. Conclusions: Boosting complementary parts of the target volume in different fractions may provide a therapeutic advantage in fractionated radiosurgery treatments of large cerebral AVMs. The strategy allows for a mean dose reduction in normal brain that may be valuable for a patient population with an otherwise normal life expectancy.

Electromagnetically induced transparency (EIT)-like transmission in side-coupled complementary split-ring resonators.

Science.gov (United States)

Guo, Yinghui; Yan, Lianshan; Pan, Wei; Luo, Bin; Wen, Kunhua; Guo, Zhen; Luo, Xiangang

2012-10-22

We investigate a plasmonic waveguide system based on side-coupled complementary split-ring resonators (CSRR), which exhibits electromagnetically induced transparency (EIT)-like transmission. LC resonance model is utilized to explain the electromagnetic responses of CSRR, which is verified by simulation results of finite difference time domain method. The electromagnetic responses of CSRR can be flexible handled by changing the asymmetry degree of the structure and the width of the metallic baffles. Cascaded CSRRs also have been studied to obtain EIT-like transmission at visible and near-infrared region, simultaneously.

Dengzhanhua preparations for acute cerebral infarction.

Science.gov (United States)

Cao, Wenzhai; Liu, Weimin; Wu, Taixiang; Zhong, Dechao; Liu, Guanjian

2008-10-08

Dengzhanhua preparations are widely used in China. Many controlled trials have been undertaken to investigate the efficacy of dengzhanhua preparations in the treatment of acute cerebral infarction. To assess whether dengzhanhua preparations are effective and safe at improving outcomes in patients with acute cerebral infarction. We searched the Cochrane Stroke Group Trials Register (last searched October 2007), the Chinese Stroke Trials Register (last searched June 2006), the trials register of the Cochrane Complementary Medicine Field (last searched June 2006), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 2 2006), MEDLINE (1966 to June 2006), EMBASE (1980 to June 2006), AMED (the Allied and Complementary Medicine Database, 1985 to June 2006), the China Biological Medicine Database (CBM-disc, 1979 to June 2006), and Chinese Knowledge Infrastructure (CNKI,1994 to October 2007). We also searched the reference lists of relevant articles. Randomised and quasi-randomised controlled clinical trials of dengzhanhua preparations regardless of duration, dosage and route of administration in patients with confirmed acute cerebral infarction. Two review authors independently applied the inclusion criteria, assessed trial quality, and extracted the data. We included nine trials, all conducted in China, involving 723 participants. The method of randomisation and concealment was poorly described. The included trials compared dengzhanhua injection plus routine therapy with routine therapy alone. Patients were enrolled up to one week after the onset of stroke. No trials reported data on the pre-specified primary or secondary outcomes. In a post-hoc comparison of dengzhanhua injection plus routine therapy versus routine therapy alone, dengzhanhua injection showed a statistically significant benefit on the outcome 'marked neurologic improvement' (relative risk 1.53; 95% confidence interval 1.36 to 1.72). No serious adverse effects were

A Case of Isolated Middle Cerebral Artery Stenosis with Hemichorea and Moyamoya Pattern Collateralization

Directory of Open Access Journals (Sweden)

Seok Jong Chung

2013-05-01

Full Text Available Isolated middle cerebral artery (MCA stenosis in young patients with no other medical condition may be a unique pathologic entity with a benign long-term course. Generally, moyamoya disease shows a progression of stenosis from internal cerebral artery (ICA to other intracranial vessel. A 26-year-old woman was admitted for choreic movements of the right arm and leg. Brain magnetic resonance imaging showed no stroke. Conventional angiography revealed 48% stenosis of the left M1 without ICA stenosis. Single photon emission computed tomography revealed perfusion asymmetry after acetazolamide injection, suggesting decreased uptake in the left basal ganglia and the cerebral cortex. Her hemichorea was mildly decreased with risperidone. One year later, follow-up angiography showed complete occlusion of the left M1 with neovascularization suggestive of moyamoya disease. The patient underwent bypass surgery and her hemichorea disappeared. This may be an atypical presentation of moyamoya disease. The bypass surgery was an effective measure for restoring the vascular insufficiency and, resultantly, controlling her hemichorea.

Evidence for developmental programming of cerebral laterality in humans.

Directory of Open Access Journals (Sweden)

Alexander Jones

2011-02-01

Full Text Available Adverse fetal environments are associated with depression, reduced cognitive ability and increased stress responsiveness in later life, but underlying mechanisms are unknown. Environmental pressures on the fetus, resulting from variations in placental function and maternal nutrition, health and stress might alter neurodevelopment, promoting the development of some brain regions over others. As asymmetry of cerebral activity, with greater right hemisphere activity, has been associated with psychopathology, we hypothesized that regional specialization during fetal life might be reflected persistently in the relative activity of the cerebral hemispheres. We tested this hypothesis in 140 healthy 8-9 year-old children, using tympanic membrane temperature to assess relative blood flow to the cerebral hemispheres at rest and following psychosocial stress (Trier Social Stress Test for Children. Their birth weight and placental weight had already been measured when their mothers took part in a previous study of pregnancy outcomes. We found that children who had a smaller weight at birth had evidence of greater blood flow to the right hemisphere than to the left hemisphere (r = -.09, P = .29 at rest; r = -.18, P = .04 following stress. This finding was strengthened if the children had a relatively low birth weight for their placental weight (r = -.17, P = .05 at rest; r = -.31, P = .0005 following stress. Our findings suggest that lateralization of cerebral activity is influenced persistently by early developmental experiences, with possible consequences for long-term neurocognitive function.

Lowering of Asymmetry

Indian Academy of Sciences (India)

et al. 2002, 2003). The N–S asymmetries of different activity manifestations have been .... 2006), the N–S asymmetry of FISXR. (Joshi et al. 2015). In the present study, we use this ..... Howe, R., Christensen-Dalsgaard, J., Hill, F., Komm, R. W.,.

Influence of different approaches to training of main movements on physical fitness of 4 years boys with various motor asymmetry

Directory of Open Access Journals (Sweden)

L. L. Galamandjuk

2015-05-01

Full Text Available Purpose: determination of effectiveness of different training main movements’ methods in physical fitness improvement of boys with different manual motor asymmetry. Material: 50 boys with ambidexterity (4 years old age took part in the research. There was used the following: oral questioning, dynamometry and methodic by M.M. Bezrukikh. Results: usage of one of variants of “symmetric” approach determines specificities of motor qualities’ development: among boys with ambidexterity in motor asymmetry variant “first with passive hand, then with active one” and variant “first with active and then with passive hand” ensure improvement of all tested qualities (except flexibility and quickness. Boys with right orientation of manual motor asymmetry demonstrated improvement of all qualities (except coordination in ballistic movements for accuracy, fulfilled by right arm in the first variant. In the second variant all qualities (except already mentioned quickness are improved. Conclusions: with any orientation of manual motor asymmetry the necessary condition of high activity and successful child’s training is development of interaction between cerebral semi-spheres. Coordinated movements by left and right arms strengthen such interaction. That is why it is purposeful to consequently fulfill every movement by every arm and by two arms simultaneously.

Influence of different approaches to training of main movements on physical fitness of 4 years boys with various motor asymmetry

Directory of Open Access Journals (Sweden)

Galamandjuk L. L.

2015-04-01

Full Text Available Purpose: determination of effectiveness of different training main movements’ methods in physical fitness improvement of boys with different manual motor asymmetry. Material: 50 boys with ambidexterity (4 years old age took part in the research. There was used the following: oral questioning, dynamometry and methodic by M.M. Bezrukikh. Results: usage of one of variants of “symmetric” approach determines specificities of motor qualities’ development: among boys with ambidexterity in motor asymmetry variant “first with passive hand, then with active one” and variant “first with active and then with passive hand” ensure improvement of all tested qualities (except flexibility and quickness. Boys with right orientation of manual motor asymmetry demonstrated improvement of all qualities (except coordination in ballistic movements for accuracy, fulfilled by right arm in the first variant. In the second variant all qualities (except already mentioned quickness are improved. Conclusions: with any orientation of manual motor asymmetry the necessary condition of high activity and successful child’s training is development of interaction between cerebral semi-spheres. Coordinated movements by left and right arms strengthen such interaction. That is why it is purposeful to consequently fulfill every movement by every arm and by two arms simultaneously.

Significance of postoperative crossed cerebellar hypoperfusion in patients with cerebral hyperperfusion following carotid endarterectomy: SPECT study

Energy Technology Data Exchange (ETDEWEB)

Ogasawara, Kuniaki; Kobayashi, Masakazu; Suga, Yasunori; Chida, Kohei; Saito, Hideo; Komoribayashi, Nobukazu; Otawara, Yasunari; Ogawa, Akira [Iwate Medical University, Department of Neurosurgery, Morioka (Japan); Iwate Medical University, Cyclotron Research Center, Morioka (Japan)

2008-01-15

Cerebral hyperperfusion after carotid endarterectomy (CEA) results in cerebral hyperperfusion syndrome and cognitive impairment. The goal of the present study was to clarify the clinical significance of postoperative crossed cerebellar hypoperfusion (CCH) in patients with cerebral hyperperfusion after CEA by assessing brain perfusion with single-photon emission computed tomography (SPECT). Brain perfusion was quantitatively measured using SPECT and the [{sup 123}I]N-isopropyl-p-iodoamphetamine-autoradiography method before and immediately after CEA and on the third postoperative day in 80 patients with ipsilateral internal carotid artery stenosis ({>=}70%). Postoperative CCH was determined by differences between asymmetry of perfusion in bilateral cerebellar hemispheres before and after CEA. Neuropsychological testing was also performed preoperatively and at the first postoperative month. Eleven patients developed cerebral hyperperfusion (cerebral blood flow increase of {>=}100% compared with preoperative values) on SPECT imaging performed immediately after CEA. In seven of these patients, CCH was observed on the third postoperative day. All three patients with hyperperfusion syndrome exhibited cerebral hyperperfusion and CCH on the third postoperative day and developed postoperative cognitive impairment. Of the eight patients with asymptomatic hyperperfusion, four exhibited CCH despite resolution of cerebral hyperperfusion on the third postoperative day, and three of these patients experienced postoperative cognitive impairment. In contrast, four patients without postoperative CCH did not experience postoperative cognitive impairment. The presence of postoperative CCH with concomitant cerebral hyperperfusion reflects the development of hyperperfusion syndrome. Further, the presence of postoperative CCH in patients with cerebral hyperperfusion following CEA suggests development of postoperative cognitive impairment, even when asymptomatic. (orig.)

Significance of postoperative crossed cerebellar hypoperfusion in patients with cerebral hyperperfusion following carotid endarterectomy: SPECT study

International Nuclear Information System (INIS)

Ogasawara, Kuniaki; Kobayashi, Masakazu; Suga, Yasunori; Chida, Kohei; Saito, Hideo; Komoribayashi, Nobukazu; Otawara, Yasunari; Ogawa, Akira

2008-01-01

Cerebral hyperperfusion after carotid endarterectomy (CEA) results in cerebral hyperperfusion syndrome and cognitive impairment. The goal of the present study was to clarify the clinical significance of postoperative crossed cerebellar hypoperfusion (CCH) in patients with cerebral hyperperfusion after CEA by assessing brain perfusion with single-photon emission computed tomography (SPECT). Brain perfusion was quantitatively measured using SPECT and the [ 123 I]N-isopropyl-p-iodoamphetamine-autoradiography method before and immediately after CEA and on the third postoperative day in 80 patients with ipsilateral internal carotid artery stenosis (≥70%). Postoperative CCH was determined by differences between asymmetry of perfusion in bilateral cerebellar hemispheres before and after CEA. Neuropsychological testing was also performed preoperatively and at the first postoperative month. Eleven patients developed cerebral hyperperfusion (cerebral blood flow increase of ≥100% compared with preoperative values) on SPECT imaging performed immediately after CEA. In seven of these patients, CCH was observed on the third postoperative day. All three patients with hyperperfusion syndrome exhibited cerebral hyperperfusion and CCH on the third postoperative day and developed postoperative cognitive impairment. Of the eight patients with asymptomatic hyperperfusion, four exhibited CCH despite resolution of cerebral hyperperfusion on the third postoperative day, and three of these patients experienced postoperative cognitive impairment. In contrast, four patients without postoperative CCH did not experience postoperative cognitive impairment. The presence of postoperative CCH with concomitant cerebral hyperperfusion reflects the development of hyperperfusion syndrome. Further, the presence of postoperative CCH in patients with cerebral hyperperfusion following CEA suggests development of postoperative cognitive impairment, even when asymptomatic. (orig.)

Asymmetry and coherence weight of quantum states

Science.gov (United States)

Bu, Kaifeng; Anand, Namit; Singh, Uttam

2018-03-01

The asymmetry of quantum states is an important resource in quantum information processing tasks such as quantum metrology and quantum communication. In this paper, we introduce the notion of asymmetry weight—an operationally motivated asymmetry quantifier in the resource theory of asymmetry. We study the convexity and monotonicity properties of asymmetry weight and focus on its interplay with the corresponding semidefinite programming (SDP) forms along with its connection to other asymmetry measures. Since the SDP form of asymmetry weight is closely related to asymmetry witnesses, we find that the asymmetry weight can be regarded as a (state-dependent) asymmetry witness. Moreover, some specific entanglement witnesses can be viewed as a special case of an asymmetry witness—which indicates a potential connection between asymmetry and entanglement. We also provide an operationally meaningful coherence measure, which we term coherence weight, and investigate its relationship to other coherence measures like the robustness of coherence and the l1 norm of coherence. In particular, we show that for Werner states in any dimension d all three coherence quantifiers, namely, the coherence weight, the robustness of coherence, and the l1 norm of coherence, are equal and are given by a single letter formula.

Technetium-99m HM-PAO-SPECT study of regional cerebral perfusion in early Alzheimer's disease

International Nuclear Information System (INIS)

Perani, D.; Di Piero, V.; Vallar, G.

1988-01-01

Regional cerebral perfusion was evaluated by single photon emission computed tomography (SPECT) using technetium-99m hexamethylpropyleneamine oxime ([/sup 99m/Tc]HM-PAO) in sixteen patients with Alzheimer's disease (AD) in early clinical phase and in 16 healthy elderly controls. In all patients transmission computed tomography (TCT) and/or magnetic resonance imaging (MRI) did not show focal brain abnormalities. Relative to normal subjects, AD patients showed significant reductions in cortical/cerebellar activity ratio: cortical perfusion was globally depressed with the largest reductions in frontal and posterior temporo-parietal cortices. Asymmetries of relative perfusion between cerebral hemispheres were also demonstrated when language was affected or visuospatial functions were unevenly impaired. In patients with early AD, SPECT provides functional information to be compared with clinical and psychometric data

Measurements of W Charge Asymmetry

Energy Technology Data Exchange (ETDEWEB)

Holzbauer, J. L. [Mississippi U.

2015-10-06

We discuss W boson and lepton charge asymmetry measurements from W decays in the electron channel, which were made using 9.7 fb$^{-1}$ of RunII data collected by the D0 detector at the Fermilab Tevatron Collider. The electron charge asymmetry is presented as a function of pseudo-rapidity out to |$\\eta$| $\\le$ 3.2, in five symmetric and asymmetric kinematic bins of electron transverse momentum and the missing transverse energy of the event. We also give the W charge asymmetry as a function of W boson rapidity. The asymmetries are compared with next-to-leading order perturbative quantum chromodynamics calculations. These charge asymmetry measurements will allow more accurate determinations of the proton parton distribution functions and are the most precise to date.

Case-control study of six genes asymmetrically expressed in the two cerebral hemispheres: association of BAIAP2 with attention-deficit/hyperactivity disorder

DEFF Research Database (Denmark)

Ribasés, Marta; Bosch, Rosa; Hervás, Amaia

2009-01-01

BACKGROUND: Attention-deficit/hyperactivity disorder (ADHD) is a childhood-onset neuropsychiatric disease that persists into adulthood in at least 30% of patients. There is evidence suggesting that abnormal left-right brain asymmetries in ADHD patients may be involved in a variety of ADHD......-related cognitive processes, including sustained attention, working memory, response inhibition and planning. Although mechanisms underlying cerebral lateralization are unknown, left-right cortical asymmetry has been associated with transcriptional asymmetry at embryonic stages and several genes differentially...... expressed between hemispheres have been identified. METHODS: We selected six functional candidate genes showing at least 1.9-fold differential expression between hemispheres (BAIAP2, DAPPER1, LMO4, NEUROD6, ATP2B3, and ID2) and performed a case-control association study in an initial Spanish sample of 587...

The influence of response competition on cerebral asymmetries for processing hierarchical stimuli revealed by ERP recordings

OpenAIRE

Malinowski, Peter; Hübner, Ronald; Keil, Andreas; Gruber, Thomas

2002-01-01

It is widely accepted that the left and right hemispheres differ with respect to the processing of global and local aspects of visual stimuli. Recently, behavioural experiments have shown that this processing asymmetry strongly depends on the response competition between the global and local levels of a stimulus. Here we report electrophysiological data that underline this observation. Hemispheric differences for global/local processing were mainly observed for responseincompatible stimuli an...

Improvements in muscle symmetry in children with cerebral palsy after equine-assisted therapy (hippotherapy).

Science.gov (United States)

Benda, William; McGibbon, Nancy H; Grant, Kathryn L

2003-12-01

To evaluate the effect of hippotherapy (physical therapy utilizing the movement of a horse) on muscle activity in children with spastic cerebral palsy. Pretest/post-test control group. Therapeutic Riding of Tucson (TROT), Tucson, AZ. Fifteen (15) children ranging from 4 to 12 years of age diagnosed with spastic cerebral palsy. Children meeting inclusion criteria were randomized to either 8 minutes of hippotherapy or 8 minutes astride a stationary barrel. Remote surface electromyography (EMG) was used to measure muscle activity of the trunk and upper legs during sitting, standing, and walking tasks before and after each intervention. After hippotherapy, significant improvement in symmetry of muscle activity was noted in those muscle groups displaying the highest asymmetry prior to hippotherapy. No significant change was noted after sitting astride a barrel. Eight minutes of hippotherapy, but not stationary sitting astride a barrel, resulted in improved symmetry in muscle activity in children with spastic cerebral palsy. These results suggest that the movement of the horse rather than passive stretching accounts for the measured improvements.

Fetal cerebral imaging - ultrasound vs. MRI: an update.

Science.gov (United States)

Blondiaux, Eléonore; Garel, Catherine

2013-11-01

The purpose of this article is to analyze the advantages and limitations of prenatal ultrasonography (US) and magnetic resonance imaging (MRI) in the evaluation of the fetal brain. These imaging modalities should not be seen as competitive but rather as complementary. There are wide variations in the world regarding screening policies, technology, skills, and legislation about termination of pregnancy, and these variations markedly impact on the way of using prenatal imaging. According to the contribution expected from each technique and to local working conditions, one should choose the most appropriate imaging modality on a case-by-case basis. The advantages and limitations of US and MRI in the setting of fetal brain imaging are displayed. Different anatomical regions (midline, ventricles, subependymal area, cerebral parenchyma, pericerebral space, posterior fossa) and pathological conditions are analyzed and illustrated in order to compare the respective contribution of each technique. An accurate prenatal diagnosis of cerebral abnormalities is of utmost importance for prenatal counseling.

Asymmetry in the brain influenced the neurological deficits and infarction volume following the middle cerebral artery occlusion in rats

OpenAIRE

Zhang Meizeng; Gao Huanmin

2008-01-01

Abstract Background Paw preference in rats is similar to human handedness, which may result from dominant hemisphere of rat brain. However, given that lateralization is the uniqueness of the humans, many researchers neglect the differences between the left and right hemispheres when selecting the middle cerebral artery occlusion (MCAO) in rats. The aim of this study was to evaluate the effect of ischemia in the dominant hemisphere on neurobehavioral function and on the cerebral infarction vol...

[Diagnosis of facial and craniofacial asymmetry].

Science.gov (United States)

Arnaud, E; Marchac, D; Renier, D

2001-10-01

Craniofacial asymmetry is caused by various aetiologies but clinical examination remains the most important criteria since minor asymmetry is always present. The diagnosis can be confirmed by anthropometric measurements and radiological examinations but only severe asymmetries or asymmetries with an associated functional impairment should be treated. The treatment depends on the cause, and on the time of appearance. Congenital asymmetries might be treated early, during the first year of life if a craniosynostosis is present. Hemifacial microsomia are treated later if there is no breathing impairment. Since the pediatricians have recommended the dorsal position for infant sleeping, an increasing number of posterior flattening of the skull has been appearing, and could be prevented by adequate nursing. Other causes of craniofacial asymmetries are rare and should be adapted to the cause (tumors, atrophies, neurological paralysis, hypertrophies) by a specialized multidisciplinar team.

Assessing and conceptualizing frontal EEG asymmetry: An updated primer on recording, processing, analyzing, and interpreting frontal alpha asymmetry.

Science.gov (United States)

Smith, Ezra E; Reznik, Samantha J; Stewart, Jennifer L; Allen, John J B

2017-01-01

Frontal electroencephalographic (EEG) alpha asymmetry is widely researched in studies of emotion, motivation, and psychopathology, yet it is a metric that has been quantified and analyzed using diverse procedures, and diversity in procedures muddles cross-study interpretation. The aim of this article is to provide an updated tutorial for EEG alpha asymmetry recording, processing, analysis, and interpretation, with an eye towards improving consistency of results across studies. First, a brief background in alpha asymmetry findings is provided. Then, some guidelines for recording, processing, and analyzing alpha asymmetry are presented with an emphasis on the creation of asymmetry scores, referencing choices, and artifact removal. Processing steps are explained in detail, and references to MATLAB-based toolboxes that are helpful for creating and investigating alpha asymmetry are noted. Then, conceptual challenges and interpretative issues are reviewed, including a discussion of alpha asymmetry as a mediator/moderator of emotion and psychopathology. Finally, the effects of two automated component-based artifact correction algorithms-MARA and ADJUST-on frontal alpha asymmetry are evaluated. Copyright © 2016 Elsevier B.V. All rights reserved.

Dichotic listening in patients with situs inversus: brain asymmetry and situs asymmetry.

Science.gov (United States)

Tanaka, S; Kanzaki, R; Yoshibayashi, M; Kamiya, T; Sugishita, M

1999-06-01

In order to investigate the relation between situs asymmetry and functional asymmetry of the human brain, a consonant-vowel syllable dichotic listening test known as the Standard Dichotic Listening Test (SDLT) was administered to nine subjects with situs inversus (SI) that ranged in age from 6 to 46 years old (mean of 21.8 years old, S.D. = 15.6); the four males and five females all exhibited strong right-handedness. The SDLT was also used to study twenty four age-matched normal subjects that were from 6 to 48 years old (mean 21.7 years old, S.D. = 15.3); the twelve males and twelve females were all strongly right-handed and served as a control group. Eight out of the nine subjects (88.9%) with SI more often reproduced the sounds from the right ear than sounds from the left ear; this is called right ear advantage (REA). The ratio of REA in the control group was almost the same, i.e., nineteen out of the twenty-four subjects (79.1%) showed REA. Results of the present study suggest that the left-right reversal in situs inversus does not involve functional asymmetry of the brain. As such, the system that produces functional asymmetry in the human brain must independently recognize laterality from situs asymmetry.

Asymmetry in infants’ selective attention to facial features during visual processing of infant-directed speech

Directory of Open Access Journals (Sweden)

Nicholas A Smith

2013-09-01

Full Text Available Two experiments used eye tracking to examine how infant and adult observers distribute their eye gaze on videos of a mother producing infant- and adult-directed speech. Both groups showed greater attention to the eyes than to the nose and mouth, as well as an asymmetrical focus on the talker’s right eye for infant-directed speech stimuli. Observers continued to look more at the talker’s apparent right eye when the video stimuli were mirror flipped, suggesting that the asymmetry reflects a perceptual processing bias rather than a stimulus artifact, which may be related to cerebral lateralization of emotion processing.

Experimental investigation of transverse spin asymmetries in muon-p SIDIS processes: Collins asymmetries

CERN Document Server

Adolph, C.; Alexakhin, V.Yu.; Alexandrov, Yu.; Alexeev, G.D.; Amoroso, A.; Antonov, A.A.; Austregesilo, A.; Badelek, B.; Balestra, F.; Barth, J.; Baum, G.; Bedfer, Y.; Bernhard, J.; Bertini, R.; Bettinelli, M.; Bicker, K.; Bieling, J.; Birsa, R.; Bisplinghoff, J.; Bordalo, P.; Bradamante, F.; Braun, C.; Bravar, A.; Bressan, A.; Burtin, E.; Capozza, L.; Chiosso, M.; Chung, S.U.; Cicuttin, A.; Crespo, M.L.; Dalla Torre, S.; Das, S.; Dasgupta, S.S.; Dasgupta, S.; Denisov, O.Yu.; Dhara, L.; Donskov, S.V.; Doshita, N.; Duic, V.; Dunnweber, W.; Dziewiecki, M.; Efremov, A.; Elia, C.; Eversheim, P.D.; Eyrich, W.; Faessler, M.; Ferrero, A.; Filin, A.; Finger, M.; Fischer, H.; Franco, C.; von Hohenesche, N.du Fresne; Friedrich, J.M.; Frolov, V.; Garfagnini, R.; Gautheron, F.; Gavrichtchouk, O.P.; Gerassimov, S.; Geyer, R.; Giorgi, M.; Gnesi, I.; Gobbo, B.; Goertz, S.; Grabmuller, S.; Grasso, A.; Grube, B.; Gushterski, R.; Guskov, A.; Guthorl, T.; Haas, F.; von Harrach, D.; Heinsius, F.H.; Herrmann, F.; Hess, C.; Hinterberger, F.; Horikawa, N.; Hoppner, Ch.; d'Hose, N.; Ishimoto, S.; Ivanov, O.; Ivanshin, Yu.; Iwata, T.; Jahn, R.; Jary, V.; Jasinski, P.; Joosten, R.; Kabuss, E.; Kang, D.; Ketzer, B.; Khaustov, G.V.; Khokhlov, Yu.A.; Kisselev, Yu.; Klein, F.; Klimaszewski, K.; Koblitz, S.; Koivuniemi, J.H.; Kolosov, V.N.; Kondo, K.; Konigsmann, K.; Konorov, I.; Konstantinov, V.F.; Korzenev, A.; Kotzinian, A.M.; Kouznetsov, O.; Kramer, M.; Kroumchtein, Z.V.; Kunne, F.; Kurek, K.; Lauser, L.; Lednev, A.A.; Lehmann, A.; Levorato, S.; Lichtenstadt, J.; Liska, T.; Maggiora, A.; Magnon, A.; Makke, N.; Mallot, G.K.; Mann, A.; Marchand, C.; Martin, A.; Marzec, J.; Matsuda, T.; Meshcheryakov, G.; Meyer, W.; Michigami, T.; Mikhailov, Yu.V.; Moinester, M.A.; Morreale, A.; Mutter, A.; Nagaytsev, A.; Nagel, T.; Negrini, T.; Nerling, F.; Neubert, S.; Neyret, D.; Nikolaenko, V.I.; Nowak, W.D.; Nunes, A.S.; Olshevsky, A.G.; Ostrick, M.; Padee, A.; Panknin, R.; Panzieri, D.; Parsamyan, B.; Paul, S.; Perevalova, E.; Pesaro, G.; Peshekhonov, D.V.; Piragino, G.; Platchkov, S.; Pochodzalla, J.; Polak, J.; Polyakov, V.A.; Pretz, J.; Quaresma, M.; Quintans, C.; Rajotte, J.F.; Ramos, S.; Rapatsky, V.; Reicherz, G.; Richter, A.; Rocco, E.; Rondio, E.; Rossiyskaya, N.S.; Ryabchikov, D.I.; Samoylenko, V.D.; Sandacz, A.; Sapozhnikov, M.G.; Sarkar, S.; Savin, I.A.; Sbrizzai, G.; Schiavon, P.; Schill, C.; Schluter, T.; Schmidt, K.; Schmitt, L.; Schonning, K.; Schopferer, S.; Schott, M.; Schroder, W.; Shevchenko, O.Yu.; Silva, L.; Sinha, L.; Sissakian, A.N.; Slunecka, M.; Smirnov, G.I.; Sosio, S.; Sozzi, F.; Srnka, A.; Steiger, L.; Stolarski, M.; Sulc, M.; Sulej, R.; Suzuki, H.; Sznajder, P.; Takekawa, S.; Wolbeek, J.Ter; Tessaro, S.; Tessarotto, F.; Tkatchev, L.G.; Uhl, S.; Uman, I.; Vandenbroucke, M.; Virius, M.; Vlassov, N.V.; Wang, L.; Wilfert, M.; Windmolders, R.; Wislicki, W.; Wollny, H.; Zaremba, K.; Zavertyaev, M.; Zemlyanichkina, E.; Ziembicki, M.; Zhuravlev, N.; Zvyagin, A.

2012-10-31

The COMPASS Collaboration at CERN has measured the transverse spin azimuthal asymmetry of charged hadrons produced in semi-inclusive deep inelastic scattering using a 160 GeV positive muon beam and a transversely polarised NH_3 target. The Collins asymmetry of the proton was extracted in the Bjorken x range 0.003asymmetries for negative and positive hadrons are similar in magnitude and opposite in sign. They are compatible with model calculations in which the u-quark transversity is opposite in sign and somewhat larger than the d-quark transversity distribution function. The asymmetry is extracted as a function of Bjorken $x$, the relative hadron energy $z$ and the hadron transverse momentum p_T^h. The high statistics and quality of the data also allow for more detailed investigations of the dependence on the ki...

Fluctuating Asymmetry of Human Populations: A Review

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John H. Graham

2016-12-01

Full Text Available Fluctuating asymmetry, the random deviation from perfect symmetry, is a widely used population-level index of developmental instability, developmental noise, and robustness. It reflects a population’s state of adaptation and genomic coadaptation. Here, we review the literature on fluctuating asymmetry of human populations. The most widely used bilateral traits include skeletal, dental, and facial dimensions; dermatoglyphic patterns and ridge counts; and facial shape. Each trait has its advantages and disadvantages, but results are most robust when multiple traits are combined into a composite index of fluctuating asymmetry (CFA. Both environmental (diet, climate, toxins and genetic (aneuploidy, heterozygosity, inbreeding stressors have been linked to population-level variation in fluctuating asymmetry. In general, these stressors increase average fluctuating asymmetry. Nevertheless, there have been many conflicting results, in part because (1 fluctuating asymmetry is a weak signal in a sea of noise; and (2 studies of human fluctuating asymmetry have not always followed best practices. The most serious concerns are insensitive asymmetry indices (correlation coefficient and coefficient of indetermination, inappropriate size scaling, unrecognized mixture distributions, inappropriate corrections for directional asymmetry, failure to use composite indices, and inattention to measurement error. Consequently, it is often difficult (or impossible to compare results across traits, and across studies.

Changes of rCBF 99mTc-HMPAO SPECT in a selected disorders

International Nuclear Information System (INIS)

Junik, R.

2003-01-01

With single photon emission computer tomography (SPECT) and HMPAO a noninvasive examination of regional cerebral blood flow can be performed (rCBF). The purpose of the SPECT examinations was to define the location and magnitude of blood flow disorder in selected diseases and the assessment of the results as complementary to morphological tests CT and MRI or functional tests, such as EEG. The examinations were carried out in 455 patients: 91 - patients with depression, 29 - congenital hypothyroidism, 66 - migraine, 34 - epilepsy, 6 - Landau-Kleffner syndrome, 20 - Alzheimer disease, 55 - with suspected Alzheimer disease, 105 - cerebral stroke, and 48 - transient cerebral ischemia. The control group comprised of 26 subjects. The SPECT method was used to perform examinations. The images were evaluated based on semiquantitative method. The asymmetry of activity and activity referred to the referential region were measured using symmetrical ROIs localized in hypoperfusion foci. The differences in perfusion in symmetric locations exceeding 10% were considered abnormal. During the depression stage, in patients with depression, a decrease of rCBF occurred. Regression of depression results in an increase of rCBF almost in the entire cerebrum. In patients with depression, SPECT examination is a useful method to monitor course of a disease and to objectively verify the results of treatment. 2. Disorders of rCBF, a decrease and/or asymmetry, occurred in patients with congenital hypothyroidism, migraine, and epilepsy. 3. There is a relation between patterns of cerebral perfusion in stroke, visible in SPECT image, and an extent and intensity of cerebral ischemia. (author)

Fluctuating Asymmetry and Intelligence

Science.gov (United States)

Bates, Timothy C.

2007-01-01

The general factor of mental ability ("g") may reflect general biological fitness. If so, "g"-loaded measures such as Raven's progressive matrices should be related to morphological measures of fitness such as fluctuating asymmetry (FA: left-right asymmetry of a set of typically left-right symmetrical body traits such as finger…

Lepton forward-backward asymmetries

International Nuclear Information System (INIS)

Pain, R.

1992-01-01

Results of Forward-Backward Asymmetries with Leptons measured at Z 0 energies are presented. Details of the analysis by the DELPHI Collaboration are given together with the most recent values of the peak Asymmetries for electrons, muons and taus obtained by ALEPH, DELPHI, L3 and OPAL Collaborations at LEP

``Green's function'' approach & low-mode asymmetries

Science.gov (United States)

Masse, Laurent; Clark, Dan; Salmonson, Jay; MacLaren, Steve; Ma, Tammy; Khan, Shahab; Pino, Jesse; Ralph, Jo; Czajka, C.; Tipton, Robert; Landen, Otto; Kyrala, Georges; 2 Team; 1 Team

2017-10-01

Long wavelength, low mode asymmetries are believed to play a leading role in limiting the performance of current ICF implosions on NIF. These long wavelength modes are initiated and driven by asymmetries in the x-ray flux from the hohlraum; however, the underlying hydrodynamics of the implosion also act to amplify these asymmetries. The work presented here aim to deepen our understanding of the interplay of the drive asymmetries and the underlying implosion hydrodynamics in determining the final imploded configuration. This is accomplished through a synthesis of numerical modeling, analytic theory, and experimental data. In detail, we use a Green's function approach to connect the drive asymmetry seen by the capsule to the measured inflight and hot spot symmetries. The approach has been validated against a suite of numerical simulations. Ultimately, we hope this work will identify additional measurements to further constrain the asymmetries and increase hohlraum illumination design flexibility on the NIF. The technique and derivation of associated error bars will be presented. LLC, (LLNS) Contract No. DE-AC52-07NA27344.

Symmetry and Asymmetry Level Measures

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Angel Garrido

2010-04-01

Full Text Available Usually, Symmetry and Asymmetry are considered as two opposite sides of a coin: an object is either totally symmetric, or totally asymmetric, relative to pattern objects. Intermediate situations of partial symmetry or partial asymmetry are not considered. But this dichotomy on the classification lacks of a necessary and realistic gradation. For this reason, it is convenient to introduce "shade regions", modulating the degree of Symmetry (a fuzzy concept. Here, we will analyze the Asymmetry problem by successive attempts of description and by the introduction of the Asymmetry Level Function, as a new Normal Fuzzy Measure. Our results (both Theorems and Corollaries suppose to be some new and original contributions to such very active and interesting field of research. Previously, we proceed to the analysis of the state of art.

Complementary functions of the two brain hemispheres: comparisons with earlier conceptions and implications for individual and society.

Science.gov (United States)

Zeier, H

1989-07-01

The concept of different functions for the left and right cerebral hemispheres coincides in an astonishing way with earlier philosophical and psychological work which divided the human mind into two complementary functions without having a neurophysiological explanation. Representative are the ideas of Fichte, Hegel and Jung. The latter postulated the two subsystems Ego and Self and associated the conscious functions of the Ego with the intellect, the capacity for rational thought, and the Self with the mind, which also includes the emotional feelings. For the harmonic development and self-realization of man the functions of both systems in complementary interaction are required. Therefore, the current overaccentuation of the intellect and of progress directed technical-scientific thinking should be corrected by making better use of the much neglected functions of the right hemisphere.

Multiple photon emission and b quark asymmetries

International Nuclear Information System (INIS)

Jadach, S.; Ward, B.F.L.

1989-08-01

We discuss the effects of multiple photon final states in high precision tests of the SU 2L x U 1 model wherein one measures the b quark asymmetries at a very high luminosity Z 0 factory, such as the possible high luminosity upgrade of the CERN LEP collider. The specific asymmetries analyzed are the forward-backward asymmetry A FB , the left-right polarized asymmetry A LR and the polarized forward-backward asymmetry A FB,pol. . The radiative effects are found to be significant for A FB as expected, but they are not as large, on a percentage basis, as the corresponding result for muons. (author). 5 refs, 1 tab

Approach-avoidance activation without anterior asymmetry

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Andero eUusberg

2014-03-01

Full Text Available Occasionally, the expected effects of approach-avoidance motivation on anterior EEG alpha asymmetry fail to emerge, particularly in studies using affective picture stimuli. These null findings have been explained by insufficient motivational intensity of, and/or overshadowing interindividual variability within the responses to emotional pictures. These explanations were systematically tested using data from 70 students watching 5 types of affective pictures ranging from very pleasant to unpleasant. The stimulus categories reliably modulated self-reports as well as the amplitude of late positive potential, an ERP component reflecting orienting towards motivationally significant stimuli. The stimuli did not, however, induce expected asymmetry effects either for the sample or individual participants. Even while systematic stimulus-dependent individual differences emerged in self-reports as well as LPP amplitudes, the asymmetry variability was dominated by stimulus-independent interindividual variability. Taken together with previous findings, these results suggest that under some circumstances anterior asymmetry may not be an inevitable consequence of core affect. Instead, state asymmetry shifts may be overpowered by stable trait asymmetry differences and/or stimulus-independent yet situation-dependent interindividual variability, possibly caused by processes such as emotion regulation or anxious apprehension.

Single spin asymmetry for charm mesons

Energy Technology Data Exchange (ETDEWEB)

Dominguez Zacarias, G. [PIMAyC, Eje Central Lazaro Cardenas No. 152, Apdo. Postal 14-805, D.F. (Mexico); Herrera, G.; Mercado, J. [Centro de Investigacion y de Estudios Avanzados, Apdo. Postal 14-740, D.F. (Mexico)

2007-08-15

We study single spin asymmetries of D{sup 0} and D{sup -} mesons in polarized proton-proton collisions. A two component model is used to describe charm meson production. The production of D mesons occurs by recombination of the constituents present in the initial state as well as by fragmentation of quarks in the final state. This model has proved to describe the production of charm. The recombination component involves a mechanism of spin alignment that ends up in a single spin asymmetry. Experimental measurements of single spin asymmetry for pions at RHIC are compared with the model. Predictions for the asymmetry in D mesons are presented. (orig.)

Single spin asymmetry for charm mesons

International Nuclear Information System (INIS)

Dominguez Zacarias, G.; Herrera, G.; Mercado, J.

2007-01-01

We study single spin asymmetries of D 0 and D - mesons in polarized proton-proton collisions. A two component model is used to describe charm meson production. The production of D mesons occurs by recombination of the constituents present in the initial state as well as by fragmentation of quarks in the final state. This model has proved to describe the production of charm. The recombination component involves a mechanism of spin alignment that ends up in a single spin asymmetry. Experimental measurements of single spin asymmetry for pions at RHIC are compared with the model. Predictions for the asymmetry in D mesons are presented. (orig.)

Asymmetry Assessment Using Surface Topography in Healthy Adolescents

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Connie Ho

2015-08-01

Full Text Available The ability to assess geometric asymmetry in the torsos of individuals is important for detecting Adolescent Idiopathic Scoliosis (AIS. A markerless technique using Surface Topography (ST has been introduced as a non-invasive alternative to standard diagnostic radiographs. The technique has been used to identify asymmetry patterns associated with AIS. However, the presence and nature of asymmetries in the healthy population has not been properly studied. The purpose of this study is therefore to identify asymmetries and potential relationships to development factors such as age, gender, hand dominance and unilateral physical activity in healthy adolescents. Full torso scans of 83 participants were analyzed. Using Geomagic, deviation contour maps (DCMs were created by reflecting the torso along the best plane of sagittal symmetry with each spectrum normalized. Two classes of asymmetry were observed: twist and thickness each with subgroupings. Averaged interobserver and intraobserver Kappas for twist subgroupings were 0.84 and 0.84, respectively, and for thickness subgroupings were 0.53 and 0.63 respectively. Further significant relationships were observed between specific types of asymmetry and gender such as females displaying predominately twist asymmetry, and males with thickness asymmetry. However, no relationships were found between type of asymmetry and age, hand dominance or unilateral physical activity. Understanding asymmetries in healthy subjects will continue to enhance assessment ability of the markerless ST technique.

Information Asymmetry and Credit Risk

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Lorena TUPANGIU

2017-11-01

Full Text Available Information asymmetry defines relationships where an agent holds information while another does not hold it. Thus, to the extent that one of the parties to the financing agreement has information more or less accurate than another, the asymmetry of information appears to be a major constraint in the financing of a project. Banks, in their capacity of financial intermediary, operate the transfer of funds to agents in need of financing, to the borrowers, being necessary in this process to have more information in order to benefit of expertise in assessing borrowers. The research of information asymmetry and credit risk consists of interrogating the following aspects: information issues between the bank and borrowers; settlement of information issues; bank’s activism towards information asymmetry. In our approach we will look at the first aspect, namely the information issues between the bank and the borrowers.

Changes in cerebral haemodynamics in cases of post-lumbar puncture headache: a prospective transcranial Doppler ultrasound study

International Nuclear Information System (INIS)

Goebel, H.; Klostermann, H.; Lindner, V.; Schenkl, S.

1990-01-01

Transcranial Doppler ultrasonography was used in 45 patients to investigate if changes in haemodynamics in the major arteries of the brain base occurred after lumbar puncture and whether or not patients with or without post-lumbar puncture headache differ with respect to their cerebral haemodynamic parameters before and after lumbar puncture. Before lumbar puncture, patients with post-lumbar puncture headache differed from patients withoput post-lumbar puncture headache in that they showed significantly higher flow velocities and significant asymmetry of flow velocities with lateralization to the right. Patients without post-lumbar puncture headache, on the other hand, showed non-significant flow velocity lateralization to the left. Forty-eight hours after lumbar puncture, both groups demonstrated symmetrical flow velocities. In addition, only patients with post-lumbar puncture headache showed a significant reduction in the flow velocity of the right middle cerebral artery. These findings suggest that it is not only absolute flow velocity that plays a part in the event of headache; the interhemispheric relation of cerebral haemodynamics also plays a fundamental role. 14 refs., 3 figs., 2 tabs

Toroidal current asymmetry in tokamak disruptions

Science.gov (United States)

Strauss, H. R.

2014-10-01

It was discovered on JET that disruptions were accompanied by toroidal asymmetry of the toroidal plasma current I ϕ. It was found that the toroidal current asymmetry was proportional to the vertical current moment asymmetry with positive sign for an upward vertical displacement event (VDE) and negative sign for a downward VDE. It was observed that greater displacement leads to greater measured I ϕ asymmetry. Here, it is shown that this is essentially a kinematic effect produced by a VDE interacting with three dimensional MHD perturbations. The relation of toroidal current asymmetry and vertical current moment is calculated analytically and is verified by numerical simulations. It is shown analytically that the toroidal variation of the toroidal plasma current is accompanied by an equal and opposite variation of the toroidal current flowing in a thin wall surrounding the plasma. These currents are connected by 3D halo current, which is π/2 radians out of phase with the n = 1 toroidal current variations.

Systematization, distribution and territory of the caudal cerebral artery on the brain's surface of the turkey (Meleagris gallopavo

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Amarílis Díaz de Carvalho

2014-10-01

Full Text Available Thirty Meleagris gallopavo heads with their neck segments were used. Animals were contained and euthanized with the association of mebezonium iodide, embutramide and tetracaine hydrochloride (T 61, Intervet by intravenous injection. The arterial system was rinsed with cold saline solution (15°C, with 5000IU heparin and filled with red-colored latex. The samples were fixed in 20% formaldehyde for seven days. The brains were removed with a segment of cervical spinal cord and after, the dura-mater was removed and the arteries dissected. The cerebral carotid arteries, after the intercarotid anastomosis, were projected around the hypophysis, until they reached the tuber cinereum and divided into their terminal branches, the caudal branch and the rostral branch. The rostral branch was projected rostrolateralwards and gave off, in sequence, two collateral branches, the caudal cerebral and the middle cerebral arteries and the terminal branch was as cerebroethmoidal artery. The caudal cerebral artery of one antimere formed the interhemispheric artery, which gave off dorsal hemispheric branches to the convex surface of both antimeres. Its dorsal tectal mesencephalic branch, of only one antimere, originated the dorsal cerebellar artery. In the interior of the cerebral transverse fissure, after the origin of the dorsal tectal mesencephalic artery, the caudal cerebral artery emitted occipital hemispheric branches, pineal branches and medial hemispheric branches, on both antimeres. The caudal cerebral artery's territory comprehended the entire surface of the dorsal hemioptic lobe, the rostral surface of the cerebellum, the diencephalic structures, the caudal pole and the medial surface of the cerebral hemisphere and in the convex surface, the sagittal eminence except for its most rostral third. Due to the asymmetry found in the caudal cerebral arteries' ramifications, the models were classified into three types and their respective subtypes.

A voxel-based asymmetry study of the relationship between hemispheric asymmetry and language dominance in Wada tested patients.

Science.gov (United States)

Keller, Simon S; Roberts, Neil; Baker, Gus; Sluming, Vanessa; Cezayirli, Enis; Mayes, Andrew; Eldridge, Paul; Marson, Anthony G; Wieshmann, Udo C

2018-03-23

Determining the anatomical basis of hemispheric language dominance (HLD) remains an important scientific endeavor. The Wada test remains the gold standard test for HLD and provides a unique opportunity to determine the relationship between HLD and hemispheric structural asymmetries on MRI. In this study, we applied a whole-brain voxel-based asymmetry (VBA) approach to determine the relationship between interhemispheric structural asymmetries and HLD in a large consecutive sample of Wada tested patients. Of 135 patients, 114 (84.4%) had left HLD, 10 (7.4%) right HLD, and 11 (8.2%) bilateral language representation. Fifty-four controls were also studied. Right-handed controls and right-handed patients with left HLD had comparable structural brain asymmetries in cortical, subcortical, and cerebellar regions that have previously been documented in healthy people. However, these patients and controls differed in structural asymmetry of the mesial temporal lobe and a circumscribed region in the superior temporal gyrus, suggesting that only asymmetries of these regions were due to brain alterations caused by epilepsy. Additional comparisons between patients with left and right HLD, matched for type and location of epilepsy, revealed that structural asymmetries of insula, pars triangularis, inferior temporal gyrus, orbitofrontal cortex, ventral temporo-occipital cortex, mesial somatosensory cortex, and mesial cerebellum were significantly associated with the side of HLD. Patients with right HLD and bilateral language representation were significantly less right-handed. These results suggest that structural asymmetries of an insular-fronto-temporal network may be related to HLD. © 2018 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc.

Interplay among transversity induced asymmetries in hadron leptoproduction

CERN Document Server

Adolph, C.; Alexeev, M.G.; Alexeev, G.D.; Amoroso, A.; Andrieux, V.; Anosov, V.; Augustyniak, W.; Austregesilo, A.; Azevedo, C.D.R.; Badelek, B.; Balestra, F.; Barth, J.; Beck, R.; Bedfer, Y.; Bernhard, J.; Bicker, K.; Bielert, E.R.; Birsa, R.; Bisplinghoff, J.; Bodlak, M.; Boer, M.; Bordalo, P.; Bradamante, F.; Braun, C.; Bressan, A.; Buchele, M.; Burtin, E.; Chang, W.C.; Chiosso, M.; Choi, I.; Chung, S.U.; Cicuttin, A.; Crespo, M.L.; Curiel, Q.; d'Hose, N.; Dalla Torre, S.; Dasgupta, S.S.; Dasgupta, S.; Denisov, O.Yu.; Dhara, L.; Donskov, S.V.; Doshita, N.; Duic, V.; Dziewiecki, M.; Efremov, A.; Elia, C.; Eversheim, P.D.; Eyrich, W.; Ferrero, A.; Finger, M.; M. Finger jr; Fischer, H.; Franco, C.; von Hohenesche, N. du Fresne; Friedrich, J.M.; Frolov, V.; Fuchey, E.; Gautheron, F.; Gavrichtchouk, O.P.; Gerassimov, S.; Giordano, F.; Gnesi, I.; Gorzellik, M.; Grabmuller, S.; Grasso, A.; Grosse-Perdekamp, M.; Grube, B.; Grussenmeyer, T.; Guskov, A.; Haas, F.; Hahne, D.; von Harrach, D.; Hashimoto, R.; Heinsius, F.H.; Herrmann, F.; Hinterberger, F.; Horikawa, N.; Hsieh, C.Yu; Huber, S.; Ishimoto, S.; Ivanov, A.; Ivanshin, Yu.; Iwata, T.; Jahn, R.; Jary, V.; Jorg, P.; Joosten, R.; Kabuss, E.; Ketzer, B.; Khaustov, G.V.; Khokhlov, Yu. A.; Kisselev, Yu.; Klein, F.; Klimaszewski, K.; Koivuniemi, J.H.; Kolosov, V.N.; Kondo, K.; Konigsmann, K.; Konorov, I.; Konstantinov, V.F.; Kotzinian, A.M.; Kouznetsov, O.; Kramer, M.; Kremser, P.; Krinner, F.; Kroumchtein, Z.V.; Kuchinski, N.; Kunne, F.; Kurek, K.; Kurjata, R.P.; Lednev, A.A.; Lehmann, A.; Levillain, M.; Levorato, S.; Lichtenstadt, J.; Longo, R.; Maggiora, A.; Magnon, A.; Makins, N.; Makke, N.; Mallot, G.K.; Marchand, C.; Marianski, B.; Martin, A.; Marzec, J.; Matousek, J.; Matsuda, H.; Matsuda, T.; Meshcheryakov, G.; Meyer, W.; Michigami, T.; Mikhailov, Yu. V.; Miyachi, Y.; Montuenga, P.; Nagaytsev, A.; Nerling, F.; Neyret, D.; Nikolaenko, V.I.; Novy, J.; Nowak, W.D.; Nukazuka, G.; Nunes, A.S.; Olshevsky, A.G.; Orlov, I.; Ostrick, M.; Panzieri, D.; Parsamyan, B.; Paul, S.; Peng, J.C.; Pereira, F.; Pesaro, G.; Pesek, M.; Peshekhonov, D.V.; Platchkov, S.; Pochodzalla, J.; Polyakov, V.A.; Pretz, J.; Quaresma, M.; Quintans, C.; Ramos, S.; Regali, C.; Reicherz, G.; Riedl, C.; Rossiyskaya, N.S.; Ryabchikov, D.I.; Rychter, A.; Samoylenko, V.D.; Sandacz, A.; Santos, C.; Sarkar, S.; Savin, I.A.; Sbrizzai, G.; Schiavon, P.; Schmidt, K.; Schmieden, H.; Schonning, K.; Schopferer, S.; Selyunin, A.; Shevchenko, O.Yu.; Silva, L.; Sinha, L.; Sirtl, S.; Slunecka, M.; Sozzi, F.; Srnka, A.; Stolarski, M.; Sulc, M.; Suzuki, H.; Szabelski, A.; Szameitat, T.; Sznajder, P.; Takekawa, S.; Wolbeek, J. ter; Tessaro, S.; Tessarotto, F.; Thibaud, F.; Tosello, F.; Tskhay, V.; Uhl, S.; Veloso, J.; Virius, M.; Weisrock, T.; Wilfert, M.; Zaremba, K.; Zavertyaev, M.; Zemlyanichkina, E.; Ziembicki, M.; Zink, A.

2016-01-01

In the fragmentation of a transversely polarized quark several left-right asymmetries are possible for the hadrons in the jet. When only one unpolarized hadron is selected, it exhibits an azimuthal modulation known as Collins effect. When a pair of oppositely charged hadrons is observed, three asymmetries can be considered, a di-hadron asymmetry and two single hadron asymmetries. In lepton deep inelastic scattering on transversely polarized nucleons all these asymmetries are coupled with the transversity distribution. From the high statistics COMPASS data on oppositely charged hadron-pair production we have investigated for the first time the dependence of these three asymmetries on the difference of the azimuthal angles of the two hadrons. The similarity of transversity induced single and di-hadron asymmetries is discussed. A phenomenological analysis of the data allows to establish quantitative relationships among them, providing strong indication that the underlying fragmentation mechanisms are all driven ...

Bessel Weighted Asymmetries

Energy Technology Data Exchange (ETDEWEB)

Avakian, Harut [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Gamberg, Leonard [Pennsylvania State Univ., University Park, PA (United States); Rossi, Patrizia [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Prokudin, Alexei [Pennsylvania State Univ., University Park, PA (United States)

2016-05-01

We review the concept of Bessel weighted asymmetries for semi-inclusive deep inelastic scattering and focus on the cross section in Fourier space, conjugate to the outgoing hadron’s transverse momentum, where convolutions of transverse momentum dependent parton distribution functions and fragmentation functions become simple products. Individual asymmetric terms in the cross section can be projected out by means of a generalized set of weights involving Bessel functions. The procedure is applied to studies of the double longitudinal spin asymmetry in semi-inclusive deep inelastic scattering using a new dedicated Monte Carlo generator which includes quark intrinsic transverse momentum within the generalized parton model. We observe a few percent systematic offset of the Bessel-weighted asymmetry obtained from Monte Carlo extraction compared to input model calculations, which is due to the limitations imposed by the energy and momentum conservation at the given energy and hard scale Q2. We find that the Bessel weighting technique provides a powerful and reliable tool to study the Fourier transform of TMDs with controlled systematics due to experimental acceptances and resolutions with different TMD model inputs.

Mapping hemispheric symmetries, relative asymmetries, and absolute asymmetries underlying the auditory laterality effect.

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Westerhausen, René; Kompus, Kristiina; Hugdahl, Kenneth

2014-01-01

Functional hemispheric differences for speech and language processing have been traditionally studied by using verbal dichotic-listening paradigms. The commonly observed right-ear preference for the report of dichotically presented syllables is taken to reflect the left hemispheric dominance for speech processing. However, the results of recent functional imaging studies also show that both hemispheres - not only the left - are engaged by dichotic listening, suggesting a more complex relationship between behavioral laterality and functional hemispheric activation asymmetries. In order to more closely examine the hemispheric differences underlying dichotic-listening performance, we report an analysis of functional magnetic resonance imaging (fMRI) data of 104 right-handed subjects, for the first time combining an interhemispheric difference and conjunction analysis. This approach allowed for a distinction of homotopic brain regions which showed symmetrical (i.e., brain region significantly activated in both hemispheres and no activation difference between the hemispheres), relative asymmetrical (i.e., activated in both hemispheres but significantly stronger in one than the other hemisphere), and absolute asymmetrical activation patterns (i.e., activated only in one hemisphere and this activation is significantly stronger than in the other hemisphere). Symmetrical activation was found in large clusters encompassing temporal, parietal, inferior frontal, and medial superior frontal regions. Relative and absolute left-ward asymmetries were found in the posterior superior temporal gyrus, located adjacent to symmetrically activated areas, and creating a lateral-medial gradient from symmetrical towards absolute asymmetrical activation within the peri-Sylvian region. Absolute leftward asymmetry was also found in the post-central and medial superior frontal gyri, while rightward asymmetries were found in middle temporal and middle frontal gyri. We conclude that dichotic

[Orthodontic treatment of Class III patients with mandibular asymmetry].

Science.gov (United States)

Duan, Yin-Zhong; Huo, Na; Chen, Lei; Chen, Xue-Peng; Lin, Yang

2008-12-01

To investigate the treatment outcome of Class III patients with dental, functional and mild skeletal mandibular asymmetry. Thirty-five patients (14 males and 21 females) with dental, functional and mild skeletal mandibular asymmetry were selected. The age range of the patients was 7 - 22 years with a mean age of 16.5 years. Dental mandibular asymmetry was treated with expansion of maxillary arch to help the mandible returning to normal position. Functional mandibular asymmetry was treated with activator or asymmetrical protraction and Class III elastics. Mild skeletal mandibular asymmetry was treated with camouflage treatment. Good occlusal relationships were achieved and facial esthetics was greatly improved after orthodontic treatment in patients with dental and functional mandibular asymmetry. However, patients with skeletal mandibular asymmetry should be treated with both extraction and genioplasty. Orthodontic treatment was suitable for patients with dental and functional mandibular asymmetry, while combined orthodontics and surgery could get good results in patients with skeletal mandibular asymmetry.

Estimation of land-surface evaporation at four forest sites across Japan with the new nonlinear complementary method.

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Ai, Zhipin; Wang, Qinxue; Yang, Yonghui; Manevski, Kiril; Zhao, Xin; Eer, Deni

2017-12-19

Evaporation from land surfaces is a critical component of the Earth water cycle and of water management strategies. The complementary method originally proposed by Bouchet, which describes a linear relation between actual evaporation (E), potential evaporation (E po ) and apparent potential evaporation (E pa ) based on routinely measured weather data, is one of the various methods for evaporation calculation. This study evaluated the reformulated version of the original method, as proposed by Brutsaert, for forest land cover in Japan. The new complementary method is nonlinear and based on boundary conditions with strictly physical considerations. The only unknown parameter (α e ) was for the first time determined for various forest covers located from north to south across Japan. The values of α e ranged from 0.94 to 1.10, with a mean value of 1.01. Furthermore, the calculated evaporation with the new method showed a good fit with the eddy-covariance measured values, with a determination coefficient of 0.78 and a mean bias of 4%. Evaluation results revealed that the new nonlinear complementary relation performs better than the original linear relation in describing the relationship between E/E pa and E po /E pa , and also in depicting the asymmetry variation between E pa /E po and E/E po .

Parity violating asymmetries in polarized electron scattering

International Nuclear Information System (INIS)

Derman, E.; Marciano, W.J.

1979-01-01

We discuss parity violating asymmetries between the scattering of right and left-handed electrons on a variety of targets. Implications for gauge theories from recent SLAC results on deep-inelastic electron-deuterium and electron-proton scattering are examined. A derivation of the asymmetry for electron-electron scattering is given, its advantages are pointed out, and the feasibility of such a measurement is discussed. Other proposed or contemplated asymmetry experiments are reviewed and the necessity of including the Collins-Wilczek-Zee hadronic axial isoscalar current contribution in asymmetry predictions is noted

Regional cerebral blood flow pattern in normal young and aged volunteers: a 99mTc-HMPAO SPET study

International Nuclear Information System (INIS)

Catafau, A.M.; Lomena, J.; Pavia, J.; Parellada, E.; Bernardo, M.; Setoain, J.; Tolosa, E.

1996-01-01

The aim of this study was to investigate the normal pattern of regional cerebral blood flow (rCBF) distribution in normal young and aged volunteers using technetium-99m hexamethylpropylene amine oxime ( 99m -Tc-HMPAO) as a tracer. The region brain perfusion of young and aged subjects was compared, especially regarding rCBF differences due to age and gender, and interhemispheric rCBF asymmetries. Sixty-eight right-handed normal volunteers -40 young (mean age 29.5±6.3 years) and 28 aged (mean age 71.2±4.3 years) - were included in the study. rCBF was estimated on the basis of a semiquantitative approach by means of a left-right index and two region/reference ratios, using the cerebellum and the whole brain activity as references. A good correlation between these two region/reference ratios was found (P<0.005 in all cerebral regions). The highest rCBF ratios corresponded to the cerebellum, followed by the occipital lobe. The remaining cortical regions (temporal, parietal, frontal and basal ganglia) showed slightly lower values. The white matter showed rCBF ratios substantially lower than the grey matter. In neighter young nor aged subjects were significant rCBF differences between the genders found in any of the two region/reference indices employed. Aged sugjects showed significantly lower rCBF ratios than young subjects in the left frontal lobe and in the posterior region of the left temporal lobe. In both young and aged subjects, lower perfusion was found in the left hemisphere, except for the white matter region in both age groups and the frontal lobe in the young subjects. Aged subjects presented a slightly higher interhemispheric asymmetry in the frontal lobe. However, interhemispheric asymmetry was minimal (-1.01% to 3.14%). Consequently, a symmetrical rCBF distribution can be assumed between homologous regions, independent of age. (orig.)

PirB regulates asymmetries in hippocampal circuitry.

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Hikari Ukai

Full Text Available Left-right asymmetry is a fundamental feature of higher-order brain structure; however, the molecular basis of brain asymmetry remains unclear. We recently identified structural and functional asymmetries in mouse hippocampal circuitry that result from the asymmetrical distribution of two distinct populations of pyramidal cell synapses that differ in the density of the NMDA receptor subunit GluRε2 (also known as NR2B, GRIN2B or GluN2B. By examining the synaptic distribution of ε2 subunits, we previously found that β2-microglobulin-deficient mice, which lack cell surface expression of the vast majority of major histocompatibility complex class I (MHCI proteins, do not exhibit circuit asymmetry. In the present study, we conducted electrophysiological and anatomical analyses on the hippocampal circuitry of mice with a knockout of the paired immunoglobulin-like receptor B (PirB, an MHCI receptor. As in β2-microglobulin-deficient mice, the PirB-deficient hippocampus lacked circuit asymmetries. This finding that MHCI loss-of-function mice and PirB knockout mice have identical phenotypes suggests that MHCI signals that produce hippocampal asymmetries are transduced through PirB. Our results provide evidence for a critical role of the MHCI/PirB signaling system in the generation of asymmetries in hippocampal circuitry.

Interplay among transversity induced asymmetries in hadron leptoproduction

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C. Adolph

2016-02-01

Full Text Available In the fragmentation of a transversely polarized quark several left–right asymmetries are possible for the hadrons in the jet. When only one unpolarized hadron is selected, it exhibits an azimuthal modulation known as the Collins effect. When a pair of oppositely charged hadrons is observed, three asymmetries can be considered, a di-hadron asymmetry and two single hadron asymmetries. In lepton deep inelastic scattering on transversely polarized nucleons all these asymmetries are coupled with the transversity distribution. From the high statistics COMPASS data on oppositely charged hadron-pair production we have investigated for the first time the dependence of these three asymmetries on the difference of the azimuthal angles of the two hadrons. The similarity of transversity induced single and di-hadron asymmetries is discussed. A new analysis of the data allows quantitative relationships to be established among them, providing for the first time strong experimental indication that the underlying fragmentation mechanisms are all driven by a common physical process.

Interictal "patchy" regional cerebral blood flow patterns in migraine patients. A single photon emission computerized tomographic study

DEFF Research Database (Denmark)

Friberg, L; Olesen, J; Iversen, Helle Klingenberg

1994-01-01

In 92 migraine patients and 44 healthy control subjects we recorded regional cerebral blood flow (rCBF) with single photon emission computerized tomography and (133) Xe inhalation or with i.v. (99m) Tc-HMPAO. Migraine patients were studied interictally. A quantitated analysis of right-left asymme......In 92 migraine patients and 44 healthy control subjects we recorded regional cerebral blood flow (rCBF) with single photon emission computerized tomography and (133) Xe inhalation or with i.v. (99m) Tc-HMPAO. Migraine patients were studied interictally. A quantitated analysis of right...... rCBF images is insufficient to pick up abnormalities; (2) almost 50% of the migraine sufferers had abnormal rCBF/asymmetries. However, these are discrete compared with those typically seen during the aura phase of a migraine attack. One explanation to the patchy rCBF patterns might...

The Inherent Asymmetry of DNA Replication.

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Snedeker, Jonathan; Wooten, Matthew; Chen, Xin

2017-10-06

Semiconservative DNA replication has provided an elegant solution to the fundamental problem of how life is able to proliferate in a way that allows cells, organisms, and populations to survive and replicate many times over. Somewhat lost, however, in our admiration for this mechanism is an appreciation for the asymmetries that occur in the process of DNA replication. As we discuss in this review, these asymmetries arise as a consequence of the structure of the DNA molecule and the enzymatic mechanism of DNA synthesis. Increasing evidence suggests that asymmetries in DNA replication are able to play a central role in the processes of adaptation and evolution by shaping the mutagenic landscape of cells. Additionally, in eukaryotes, recent work has demonstrated that the inherent asymmetries in DNA replication may play an important role in the process of chromatin replication. As chromatin plays an essential role in defining cell identity, asymmetries generated during the process of DNA replication may play critical roles in cell fate decisions related to patterning and development.

Relationship between information asymmetry and cost of capital

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Fateme Rahmani

2013-01-01

Full Text Available Shareholders expected return is normally impacted by informational risk and informational asymmetry, on the other hand, creates informational risk. Thus, investors demand greater risk premium in the case of informational asymmetry and in turn corporate expenditures increase. In this study, we determine the relationship between informational asymmetry and capital cost. The study uses information of 109 companies listed in Tehran Securities Exchange over the period of 2005-2010 and the results suggest a positive and significant relationship between informational asymmetry and capital cost. In addition, the results from present research indicate that when capital markets are competitive, there is not a significant relationship between informational asymmetry and capital cost. But when markets are partially competitive there is a significant relationship between informational asymmetry and capital cost.

Asymmetry quantization and application to human mandibles

DEFF Research Database (Denmark)

Glerup, Nanna; Nielsen, Mads; Sporring, Jon

2004-01-01

of asymmetry, the statistics on asymmetry for normal and pathological anatomical structures can be compared. Symmetry is a well-known mathematical group theoretical concept. In this paper, we will mathematically define the concept of weak symmetry, including topological symmetry, which serves as a basis...... of pathological assumed non-symmetric mandibles exhibiting a statistically significant increase of asymmetry....

Spectral asymmetry for bag boundary conditions

International Nuclear Information System (INIS)

Beneventano, C G; Santangelo, E M; Wipf, A

2002-01-01

We give an expression, in terms of boundary spectral functions, for the spectral asymmetry of the Euclidean Dirac operator in two dimensions, when its domain is determined by local boundary conditions and the manifold is of product type. As an application, we explicitly evaluate the asymmetry in the case of a finite-length cylinder and check that the outcome is consistent with our general result. Finally, we study the asymmetry in a disc, which is a non-product case, and propose an interpretation

Exchange asymmetry in experimental settings

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Thomas C. Brown; Mark D. Morrison; Jacob A. Benfield; Gretchen Nurse Rainbolt; Paul A. Bell

2015-01-01

We review past trading experiments and present 11 new experiments designed to show how the trading rate responds to alterations of the experimental procedure. In agreement with earlier studies, results show that if the trade decision is converted to one resembling a choice between goods the exchange asymmetry disappears, but otherwise the asymmetry is...

Measurement of ttbar forward-backward asymmetry at CDF

CERN Multimedia

CERN. Geneva

2011-01-01

Early measurements of the forward-backward ttbar production asymmetry at CDF and D0 suggested significant asymmetries that have been interpreted as evidence for exotic gluon partners or new t-channel interactions. We present new measurements performed with 5 fb-1 of Tevatron ppbar collisions at Ecm = 1.96 TeV, recorded and analyzed at CDF. Significant inclusive asymmetries are observed in both the lepton+jets and the dilepton decay modes of the ttbar pair. In the dilepton mode, the asymmetry is observed in the reconstructed top rapidity, and in the lepton rapidity difference, which is independent of any top reconstruction. In the lepton plus jets sample, the full reconstruction of the top kinematics is used to measure the dependence of the asymmetry on the tt bar rapidity difference Delta(y) and the invariant mass M_(ttbar ) of the ttbar system. The asymmetry is found to be most significant at large Delta(y) and M_(ttbar) . For M_(ttbar) > 450 GeV/c2, the parton-level asymmetry in the t-tbar rest frame is...

Anatomical and functional asymmetry of the planum temporale

International Nuclear Information System (INIS)

Tomura, Noriaki; Fujita, Hideaki; Inugami, Atsushi; Tabata, Kenichi; Higano, Shuichi; Shishido, Fumio; Kanno, Iwao; Uemura, Kazuo

1989-01-01

The anatomical and functional asymmetry of the planum temporale was studied by means of computed tomography (CT) and positron emission tomography (PET). The subjects were 74 cases of normal CTs and 24 cases of normal PETs. Fifty of the 74 cases of normal CT were randomly picked from 36,545 cases studied from June 1983 to January 1988, while the remaining 24 cases were obtained as normal volunteers for PET. The 24 cases of PET were studied as normal volunteers who did not have any neurological abnormalities. All of the CT scans were obtained by means of a GE CT/T 9800 scanner, with 10-mm or 7.5-mm collimation parallel to the orbitomeatal plane (+15). On the CT, the anterior margin of the superior temporal gyrus sloped backward on the left in 62.2 percent of the cases and on the right in 4.1 percent. The lateral end of the anterior margin of the left superior temporal gyrus lay posterior to the corresponding point on the right in 73.0 percent of the cases. PET was obtained with a HEADTOME III scanner, with a spatial resolution of 10 mm. PET scans were taken parallel to the orbitomeatal plane (+15) and at 7.5-mm intervals. The cerebral blood flow (CBF), the metabolic rate of oxygen (CMRO 2 ), the oxygen-extraction fraction (OEF), and the blood volume (CBV) were measured by the 15 O-steady state method, while the cerebral metabolic rate of glucose (CMRGlc) was measured using 18 F-fluorodeoxyglucose. The PET measurements exhibited that the mean CBF and CMRO 2 of the left superior temporal gyrus were significantly higher than those of the right (CBF; p 2 ; p 2 obtained by PET indicated the functional dominance for language on the left. (author)

Witnessing Multipartite Entanglement by Detecting Asymmetry

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Davide Girolami

2017-03-01

Full Text Available The characterization of quantum coherence in the context of quantum information theory and its interplay with quantum correlations is currently subject of intense study. Coherence in a Hamiltonian eigenbasis yields asymmetry, the ability of a quantum system to break a dynamical symmetry generated by the Hamiltonian. We here propose an experimental strategy to witness multipartite entanglement in many-body systems by evaluating the asymmetry with respect to an additive Hamiltonian. We test our scheme by simulating asymmetry and entanglement detection in a three-qubit Greenberger–Horne–Zeilinger (GHZ diagonal state.

Cerebral microangiopathies

International Nuclear Information System (INIS)

Linn, Jennifer

2011-01-01

Cerebral microangiopathies are a very heterogenous group of diseases characterized by pathological changes of the small cerebral vessels. They account for 20 - 30 % of all ischemic strokes. Degenerative microangiopathy and sporadic cerebral amyloid angiography represent the typical acquired cerebral microangiopathies, which are found in over 90 % of cases. Besides, a wide variety of rare, hereditary microangiopathy exists, as e.g. CADASIL (Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy), Fabrys disease and MELAS syndrome (Mitochondrial myopathy, Encephalopathy, Lactic Acidosis, and Stroke-like episodes). (orig.)

Effects of Milrinone continuous intravenous infusion on global cerebral oxygenation and cerebral vasospasm after cerebral aneurysm surgical clipping

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Mohamed A. Ghanem

2014-01-01

Conclusions: Milrinone improved significantly the global cerebral oxygenation and reduced the incidence of cerebral vasospasm during the dangerous period of cerebral spasm after cerebral aneurysm clipping.

Frequency of dentofacial asymmetries: a cross-sectional study on orthodontic patients.

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Bhateja, Nita Kumari; Fida, Mubassar; Shaikh, Attiya

2014-01-01

Correction of orthodontic asymmetries is crucial to achieve functional occlusion, aesthetics and stability of post orthodontic treatment results. To date valid frequency data of dentofacial asymmetries in Pakistani orthodontic patients do not exist to document orthodontic treatment need. The objectives of this study were to determine frequency of dento-facial asymmetries, severity of dental asymmetries and to determine difference in frequency of dentofacial asymmetries in mixed and permanent dentition. The sample of this cross-sectional study comprised of 280 patients (177 females and 103 males) with no history of previous orthodontic treatment having no craniofacial anomalies. Dento-facial asymmetries were assessed from pre-treatment records of patients. Descriptive statistics were used to determine frequency of dentofacial asymmetries and severity of dental asymmetries. Chi-square test was used to determine difference in frequency of dentofacial asymmetries in mixed and permanent dentition. Seventy eight percent (219) of patients had noncoincident midlines, 67.5% (189) had mandibular midline asymmetry, 43.2% (122) had molar asymmetry, 15.7% (44) had mandibular arch asymmetry, 14.3% (40) had maxillary midline asymmetry, 13.6% (38) had maxillary arch asymmetry, 6.1% (17) had nose deviation, and 12.1% (34) had facial asymmetry and chin deviation. In most patients dental midlines were deviated from one another and from facial midline by ¼ lower incisor widths, while molar asymmetry was found in most patients by ¼ cusp width. Mandibular arch asymmetry was more frequent in permanent than mixed dentition (p = 0.054). Non-coincident dental midline is most commonly seen. Nose deviation is least commonly observed. Mandibular arch asymmetry is more frequent in permanent than mixed dentition.

On the Compton Twist-3 Asymmetries

International Nuclear Information System (INIS)

Korotkiyan, V.M.; Teryaev, O.V.

1994-01-01

The 'fermionic poles' contribution to the twist-3 single asymmetry in the gluon Compton process is calculated. The 'gluonic poles' existence seems to contradict the density matrix positivity. Qualitative predictions for the direct photon and jets asymmetries are presented. 13 refs., 2 figs

Structural Connectivity Asymmetry in the Neonatal Brain

OpenAIRE

Ratnarajah, Nagulan; Rifkin-Graboi, Anne; Fortier, Marielle V.; Chong, Yap Seng; Kwek, Kenneth; Saw, Seang-Mei; Godfrey, Keith M; Gluckman, Peter D.; Meaney, Michael J.; Qiu, Anqi

2013-01-01

Asymmetry of the neonatal brain is not yet understood at the level of structural connectivity. We utilized DTI deterministic tractography and structural network analysis based on graph theory to determine the pattern of structural connectivity asymmetry in 124 normal neonates. We tracted white matter axonal pathways characterizing interregional connections among brain regions and inferred asymmetry in left and right anatomical network properties. Our findings revealed that in neonates, small-...

Hemispheric asymmetries in dorsal language pathway white-matter tracts: A magnetic resonance imaging tractography and functional magnetic resonance imaging study.

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Silva, Guilherme; Citterio, Alberto

2017-10-01

Introduction Previous studies have shown that the arcuate fasciculus has a leftward asymmetry in right-handers that could be correlated with the language lateralisation defined by functional magnetic resonance imaging. Nonetheless, information about the asymmetry of the other fibres that constitute the dorsal language pathway is scarce. Objectives This study investigated the asymmetry of the white-matter tracts involved in the dorsal language pathway through the diffusion tensor imaging (DTI) technique, in relation to language hemispheric dominance determined by task-dependent functional magnetic resonance imaging (fMRI). Methods We selected 11 patients (10 right-handed) who had been studied with task-dependent fMRI for language areas and DTI and who had no language impairment or structural abnormalities that could compromise magnetic resonance tractography of the fibres involved in the dorsal language pathway. Laterality indices (LI) for fMRI and for the volumes of each tract were calculated. Results In fMRI, all the right-handers had left hemispheric lateralisation, and the ambidextrous subject presented right hemispheric dominance. The arcuate fasciculus LI was strongly correlated with fMRI LI ( r = 0.739, p = 0.009), presenting the same lateralisation of fMRI in seven subjects (including the right hemispheric dominant). It was not asymmetric in three cases and had opposite lateralisation in one case. The other tracts presented predominance for rightward lateralisation, especially superior longitudinal fasciculus (SLF) II/III (nine subjects), but their LI did not correlate (directly or inversely) with fMRI LI. Conclusion The fibres that constitute the dorsal language pathway have an asymmetric distribution in the cerebral hemispheres. Only the asymmetry of the arcuate fasciculus is correlated with fMRI language lateralisation.

Oil demand asymmetry in the OECD

International Nuclear Information System (INIS)

Shealy, M.T.

1990-01-01

Oil demand asymmetry exists, is significant, and can be captured with a simple demand equation using a Pmax term. The unstable parameters of the original symmetric equations suggest misspecification. Addition of a Pmax term to represent asymmetry yields stable parameters from 1982 through 1989 and so suggests proper specification. Asymmetry is significant because the short-run (and long-run) price elasticity is less than half as large when oil price falls as when price rises beyond the past peak. The lower elasticity applies both to price decreases and also to price increases for which price remains below the past peak. As long as the real oil price remains well below the 1981 peak, asymmetry implies that OECD oil demand should be less sensitive to oil price variations than in 1981. More specifically, the results shown suggest that today's oil demand elasticity should be less than half as large as the elasticity for a price increase in 1981. Forecasts from the asymmetric equations are significantly higher than the DOE base-case forecast. DOE's lower forecast is due to greater price asymmetry through 1995 and to higher long-run price elasticity beyond 1995. One reason for the higher long-run price elasticity might be greater assumed improvements in energy-efficiency than implied by the historical data

Aggression and Brain Asymmetries: A Theoretical Review

OpenAIRE

Rohlfs , Paloma; Ramirez, J. Martin

2006-01-01

The relationship between aggression and brain asymmetries has not been studied enough. The association between both concepts can be approached from two different perspectives. One perspective points to brain asymmetries underlying the emotion of anger and consequently aggression in normal people. Another one is concerned with the existence of brain asymmetries in aggressive people (e.g., in the case of suicides or psychopathies). Research on emotional processing points out the confusion betw...

Bilateral asymmetry of the humerus during growth and development.

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Blackburn, Amanda

2011-08-01

The development of handedness throughout growth can be investigated by using bilateral asymmetry of the humerus as a proxy for this trait. A large skeletal sample of nonadults from English archaeological sites was examined using standard metric techniques to assess when right-sided asymmetry first appears in the human skeleton. Results of this work indicate a change in directional asymmetry during growth and development, with infants and young children exhibiting no significant asymmetry and older children and adolescents demonstrating right-sidedness. This trend is consistent with what has been observed in previous studies of upper limb asymmetry in skeletal material and behaviorally in living children, adding further strength to the premise that biomechanical forces strongly influence bilateral asymmetry in the upper limb bones. Variability in the magnitude of asymmetry between different features of the humerus was also noted. This characteristic can be explained by differing degrees of genetic canalization, with length and articular dimensions being more strongly canalized than diaphyseal properties. Copyright © 2011 Wiley-Liss, Inc.

Geometric asymmetry driven Janus micromotors

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Zhao, Guanjia; Pumera, Martin

2014-09-01

The production and application of nano-/micromotors is of great importance. In order for the motors to work, asymmetry in their chemical composition or physical geometry must be present if no external asymmetric field is applied. In this paper, we present a ``coconut'' micromotor made of platinum through the partial or complete etching of the silica templates. It was shown that although both the inner and outer surfaces are made of the same material (Pt), motion of the structure can be observed as the convex surface is capable of generating oxygen bubbles. This finding shows that not only the chemical asymmetry of the micromotor, but also its geometric asymmetry can lead to fast propulsion of the motor. Moreover, a considerably higher velocity can be seen for partially etched coconut structures than the velocities of Janus or fully etched, shell-like motors. These findings will have great importance on the design of future micromotors.The production and application of nano-/micromotors is of great importance. In order for the motors to work, asymmetry in their chemical composition or physical geometry must be present if no external asymmetric field is applied. In this paper, we present a ``coconut'' micromotor made of platinum through the partial or complete etching of the silica templates. It was shown that although both the inner and outer surfaces are made of the same material (Pt), motion of the structure can be observed as the convex surface is capable of generating oxygen bubbles. This finding shows that not only the chemical asymmetry of the micromotor, but also its geometric asymmetry can lead to fast propulsion of the motor. Moreover, a considerably higher velocity can be seen for partially etched coconut structures than the velocities of Janus or fully etched, shell-like motors. These findings will have great importance on the design of future micromotors. Electronic supplementary information (ESI) available: Additional SEM images, data analysis, Videos S

Identification of Foot Pathologies Based on Plantar Pressure Asymmetry

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Linah Wafai

2015-08-01

Full Text Available Foot pathologies can negatively influence foot function, consequently impairing gait during daily activity, and severely impacting an individual’s quality of life. These pathologies are often painful and correspond with high or abnormal plantar pressure, which can result in asymmetry in the pressure distribution between the two feet. There is currently no general consensus on the presence of asymmetry in able-bodied gait, and plantar pressure analysis during gait is in dire need of a standardized method to quantify asymmetry. This paper investigates the use of plantar pressure asymmetry for pathological gait diagnosis. The results of this study involving plantar pressure analysis in fifty one participants (31 healthy and 20 with foot pathologies support the presence of plantar pressure asymmetry in normal gait. A higher level of asymmetry was detected at the majority of the regions in the feet of the pathological population, including statistically significant differences in the plantar pressure asymmetry in two regions of the foot, metatarsophalangeal joint 3 (MPJ3 and the lateral heel. Quantification of plantar pressure asymmetry may prove to be useful for the identification and diagnosis of various foot pathologies.

Three-dimensional assessment of facial asymmetry: A systematic review.

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Akhil, Gopi; Senthil Kumar, Kullampalayam Palanisamy; Raja, Subramani; Janardhanan, Kumaresan

2015-08-01

For patients with facial asymmetry, complete and precise diagnosis, and surgical treatments to correct the underlying cause of the asymmetry are significant. Conventional diagnostic radiographs (submento-vertex projections, posteroanterior radiography) have limitations in asymmetry diagnosis due to two-dimensional assessments of three-dimensional (3D) images. The advent of 3D images has greatly reduced the magnification and projection errors that are common in conventional radiographs making it as a precise diagnostic aid for assessment of facial asymmetry. Thus, this article attempts to review the newly introduced 3D tools in the diagnosis of more complex facial asymmetries.

Mercury exposure may influence fluctuating asymmetry in waterbirds

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Herring, Garth; Eagles-Smith, Collin A.; Ackerman, Joshua T.

2017-01-01

Variation in avian bilateral symmetry can be an indicator of developmental instability in response to a variety of stressors, including environmental contaminants. The authors used composite measures of fluctuating asymmetry to examine the influence of mercury concentrations in 2 tissues on fluctuating asymmetry within 4 waterbird species. Fluctuating asymmetry increased with mercury concentrations in whole blood and breast feathers of Forster's terns (Sterna forsteri), a species with elevated mercury concentrations. Specifically, fluctuating asymmetry in rectrix feather 1 was the most strongly correlated structural variable of those tested (wing chord, tarsus, primary feather 10, rectrix feather 6) with mercury concentrations in Forster's terns. However, for American avocets (Recurvirostra americana), black-necked stilts (Himantopus mexicanus), and Caspian terns (Hydroprogne caspia), the authors found no relationship between fluctuating asymmetry and either whole-blood or breast feather mercury concentrations, even though these species had moderate to elevated mercury exposure. The results indicate that mercury contamination may act as an environmental stressor during development and feather growth and contribute to fluctuating asymmetry of some species of highly contaminated waterbirds.

Asymmetry of the Brain: Development and Implications.

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Duboc, Véronique; Dufourcq, Pascale; Blader, Patrick; Roussigné, Myriam

2015-01-01

Although the left and right hemispheres of our brains develop with a high degree of symmetry at both the anatomical and functional levels, it has become clear that subtle structural differences exist between the two sides and that each is dominant in processing specific cognitive tasks. As the result of evolutionary conservation or convergence, lateralization of the brain is found in both vertebrates and invertebrates, suggesting that it provides significant fitness for animal life. This widespread feature of hemispheric specialization has allowed the emergence of model systems to study its development and, in some cases, to link anatomical asymmetries to brain function and behavior. Here, we present some of what is known about brain asymmetry in humans and model organisms as well as what is known about the impact of environmental and genetic factors on brain asymmetry development. We specifically highlight the progress made in understanding the development of epithalamic asymmetries in zebrafish and how this model provides an exciting opportunity to address brain asymmetry at different levels of complexity.

Quantifying cerebral asymmetries for language in dextrals and adextrals with random-effects meta analysis.

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David Peter Carey

2014-11-01

Full Text Available Speech and language-related functions tend to depend on the left hemisphere more than the right in most right-handed (dextral participants. This relationship is less clear in non-right handed (adextral people, resulting in surprisingly polarised opinion on whether or not they are as lateralised as right handers. The present analysis investigates this issue by largely ignoring methodological differences between the different neuroscientific approaches to language lateralization, as well as discrepancies in how dextral and adextral participants were recruited or defined. Here we evaluate the tendency for dextrals to be more left hemisphere dominant than adextrals, using random effects meta analyses. In spite of several limitations, including sample size (in the adextrals in particular, missing details on proportions of groups who show directional effects in many experiments, and so on, the different paradigms all point to proportionally increased left hemispheric dominance in the dextrals. These results are analysed in light of the theoretical importance of these subtle differences for understanding the cognitive neuroscience of language, as well as the unusual asymmetry in most adextrals.

Quantifying cerebral asymmetries for language in dextrals and adextrals with random-effects meta analysis

Science.gov (United States)

Carey, David P.; Johnstone, Leah T.

2014-01-01

Speech and language-related functions tend to depend on the left hemisphere more than the right in most right-handed (dextral) participants. This relationship is less clear in non-right handed (adextral) people, resulting in surprisingly polarized opinion on whether or not they are as lateralized as right handers. The present analysis investigates this issue by largely ignoring methodological differences between the different neuroscientific approaches to language lateralization, as well as discrepancies in how dextral and adextral participants were recruited or defined. Here we evaluate the tendency for dextrals to be more left hemisphere dominant than adextrals, using random effects meta analyses. In spite of several limitations, including sample size (in the adextrals in particular), missing details on proportions of groups who show directional effects in many experiments, and so on, the different paradigms all point to proportionally increased left hemispheric dominance in the dextrals. These results are analyzed in light of the theoretical importance of these subtle differences for understanding the cognitive neuroscience of language, as well as the unusual asymmetry in most adextrals. PMID:25408673

Molecular dynamics simulations of tension–compression asymmetry in nanocrystalline copper

Energy Technology Data Exchange (ETDEWEB)

Zhou, Kai, E-mail: kaizhou@aliyun.com; Liu, Bin; Shao, Shaofeng; Yao, Yijun

2017-04-04

Molecular dynamics simulations are used to investigate uniaxial tension and compression of nanocrystalline copper with mean grain sizes of 3.8–11.9 nm. The simulation results show an apparent asymmetry in the flow stress, with nanocrystalline copper stronger in compression than in tension. The asymmetry exhibits a maximum at the mean grain size of about 10 nm. The dominant mechanism of the asymmetry depends on the mean grain size. At small grain sizes, grain-boundary based plasticity dominates the asymmetry, while for large grain sizes the asymmetry mainly arises from the pressure dependent dislocation emission from grain boundaries. - Highlights: • The tension–compression asymmetry in strength exhibits a maximum at the mean grain size of about 10 nm. • The main mechanisms govern the asymmetry are grain-boundary mediated plasticity and dislocation based plasticity. • The above-mentioned mechanisms are both grain size and pressure dependent. • The transition of the asymmetry with the mean grain size is not influenced by strain rate.

Breast asymmetry and predisposition to breast cancer

OpenAIRE

Scutt, Diane; Lancaster, Gillian A; Manning, John T

2006-01-01

INTRODUCTION: It has been shown in our previous work that breast asymmetry is related to several of the known risk factors for breast cancer, and that patients with diagnosed breast cancer have more breast volume asymmetry, as measured from mammograms, than age-matched healthy women. METHODS: In the present study, we compared the breast asymmetry of women who were free of breast disease at time of mammography, but who had subsequently developed breast cancer, with that of age-matched healthy ...

Anestesia e paralisia cerebral Anestesia y parálisis cerebral Anesthesia and cerebral palsy

Directory of Open Access Journals (Sweden)

Március Vinícius M Maranhão

2005-12-01

Full Text Available JUSTIFICATIVA E OBJETIVOS: A paralisia cerebral (PC é uma doença não progressiva decorrente de lesão no sistema nervoso central, levando a um comprometimento motor do paciente. O portador de PC freqüentemente é submetido a procedimentos cirúrgicos devido a doenças usuais e situações particulares decorrentes da paralisia cerebral. Foi objetivo deste artigo revisar aspectos da paralisia cerebral de interesse para o anestesiologista, permitindo um adequado manuseio pré, intra e pós-operatório neste tipo de paciente. CONTEÚDO: O artigo aborda aspectos da paralisia cerebral como etiologia, classificação, fatores de risco, fisiopatologia, quadro clínico, diagnóstico, terapêuticas utilizadas bem como avaliação pré-operatória, medicação pré-anestésica, manuseio intra e pós-operatório, analgesia pós-operatória e dor crônica. CONCLUSÕES: O anestesiologista desempenha um papel importante na diminuição da morbidade e mortalidade anestésico-cirúrgica em pacientes portadores de paralisia cerebral. O conhecimento da fisiopatologia dos diferentes tipos de paralisia cerebral bem como das doenças associadas e suas terapêuticas é imprescindível, pois permite ao anestesiologista antecipar e prevenir complicações intra e pós-operatórias neste tipo de paciente.JUSTIFICATIVA Y OBJETIVOS: La parálisis cerebral (PC es una enfermedad no progresiva consecuente de una lesión en el sistema nervioso central, llevando a un comprometimiento motor del paciente. El portador de PC, frecuentemente es sometido a procedimientos quirúrgicos debido a enfermedades usuales y situaciones particulares consecuentes de la parálisis cerebral. El objetivo de este artículo, fue revisar aspectos de la parálisis cerebral de interés para el anestesista, permitiendo un adecuado manoseo pre, intra y posoperatorio en este tipo de paciente. CONTENIDO: El artículo aborda aspectos de la parálisis cerebral como etiología, clasificación, factores de

Azimuthal asymmetries in hard exclusive meson muoproduction off transversely polarized protons

Energy Technology Data Exchange (ETDEWEB)

Wolbeek, Johannes ter

2015-04-15

} production, which was an evidence for the existence of the transverse GPD H{sub T}. The asymmetries obtained in this analysis can help to constrain Generalized Parton Distributions. This is done by comparing the measurements to model calculations of the asymmetries in the COMPASS kinematics. In this thesis the results are compared to the model from Goloskokov and Kroll, which is in good agreement with the data. Especially in combination with results from other vector meson channels, as for example the ρ{sup 0} meson, which has already been analyzed, additional constrains on quark GPDs E{sup u} and E{sup d} are enabled. Furthermore the pion pole contribution plays an important role in hard exclusive ω production, whereby the ω channel is of special interest. Especially the three single spin asymmetries A{sup sin(φ-φs)}{sub UT}, A{sup sin(2φs-φS)}{sub UT} and A{sup sin} {sup φS}{sub UT} are expected to be sensitive to the sign of the πω form factor and therefore of great importance. The results on the first and second asymmetry are clearly in favor of a negative sign of the form factor, whereas the result on the last one is also compatible with theoretical predictions assuming a positive sign. At the moment the analysis is limited by the available statistic. Therefore more data, taken with transversely polarized protons and deuterons, will be needed. This could also allow for the investigation on heavier vector mesons like the φ and the J/ψ meson, whose production cross section is much smaller compared to the ω and the ρ{sup 0}. The complementary results from various production channels will help to further constrain the GPDs. The present fixed target experiments do not allow for a sufficient increase of statistics. But maybe in the future polarized collider experiments can achieve the needed statistics.

Regional cerebral blood flow in neuropediatrics

International Nuclear Information System (INIS)

Junik, R.

2001-01-01

Single photon emission computed tomography can effectively and non-invasively measure regional blood flow. Mostly used 99mTc-HMPAO is a safe brain imaging agent for pediatric applications. The radiation dose is acceptable. Knowledge of the normal rCBF pattern, including normal asymmetries and variations due to age, is necessary prerequisite for the evaluation and reporting of the results of 99mTc-HMPAO brain SPECT studies in clinical practice. The interpretation of he rCBF study in a child requires knowledge of normal brain maturation. The aim of the present review is to focus on the contribution to clinical developmental neurology of SPECT The clinical use of SPECT in developmental neurology are epilepsy, brain death, acute neurological loss including stroke, language disorders, cerebral palsy, high-risk neonates, hypertension due to renovascular disease, traumatic brain injury, migraine, anorexia nervosa, autism, Gilles de la Tourette syndrome, attention deficit disorder-hyperactivity, and monitoring therapy. Sedation is not routinely used, rather each child is evaluated. However, drug sedation is mandatory in some uncooperative children. (author)

Precise discussion of time-reversal asymmetries in B-meson decays

International Nuclear Information System (INIS)

Morozumi, Takuya; Okane, Hideaki; Umeeda, Hiroyuki

2015-01-01

BaBar collaboration announced that they observed time reversal (T) asymmetry through B meson system. In the experiment, time dependencies of two distinctive processes, B_−→ (B"0)-bar and (B"0)-bar →B_− (− expresses CP value) are compared with each other. In our study, we examine event number difference of these two processes. In contrast to the BaBar asymmetry, the asymmetry of events number includes the overall normalization difference for rates. Time dependence of the asymmetry is more general and it includes terms absent in one used by BaBar collaboration. Both of the BaBar asymmetry and ours are naively thought to be T-odd since two processes compared are related with flipping time direction. We investigate the time reversal transformation property of our asymmetry. Using our notation, one can see that the asymmetry is not precisely a T-odd quantity, taking into account indirect CP and CPT violation of K meson systems. The effect of ϵ_K is extracted and gives rise to O(10"−"3) contribution. The introduced parameters are invariant under rephasing of quarks so that the coefficients of our asymmetry are expressed as phase convention independent quantities. Some combinations of the asymmetry enable us to extract parameters for wrong sign decays of B_d meson, CPT violation, etc. We also study the reason why the T-even terms are allowed to contribute to the asymmetry, and find that several conditions are needed for the asymmetry to be a T-odd quantity.

A voxel-based approach to gray matter asymmetries.

Science.gov (United States)

Luders, E; Gaser, C; Jancke, L; Schlaug, G

2004-06-01

Voxel-based morphometry (VBM) was used to analyze gray matter (GM) asymmetries in a large sample (n = 60) of male and female professional musicians with and without absolute pitch (AP). We chose to examine these particular groups because previous studies using traditional region-of-interest (ROI) analyses have shown differences in hemispheric asymmetry related to AP and gender. Voxel-based methods may have advantages over traditional ROI-based methods since the analysis can be performed across the whole brain with minimal user bias. After determining that the VBM method was sufficiently sensitive for the detection of differences in GM asymmetries between groups, we found that male AP musicians were more leftward lateralized in the anterior region of the planum temporale (PT) than male non-AP musicians. This confirmed the results of previous studies using ROI-based methods that showed an association between PT asymmetry and the AP phenotype. We further observed that male non-AP musicians revealed an increased leftward GM asymmetry in the postcentral gyrus compared to female non-AP musicians, again corroborating results of a previously published study using ROI-based methods. By analyzing hemispheric GM differences across our entire sample, we were able to partially confirm findings of previous studies using traditional morphometric techniques, as well as more recent, voxel-based analyses. In addition, we found some unusually pronounced GM asymmetries in our musician sample not previously detected in subjects unselected for musical training. Since we were able to validate gender- and AP-related brain asymmetries previously described using traditional ROI-based morphometric techniques, the results of our analyses support the use of VBM for examinations of GM asymmetries.

Cerebral atrophic and degenerative changes following various cerebral diseases, (1)

International Nuclear Information System (INIS)

Kino, Masao; Anno, Izumi; Yano, Yuhiko; Anno, Yasuro.

1980-01-01

Patients having cerebral atrophic and degenerative changes following hypoglycemia, cerebral contusion, or cerebral hypoxia including cerebrovascular disorders were reported. Description was made as to cerebral changes visualized on CT images and clinical courses of a patient who revived 10 minutes after heart stoppage during neurosurgery, a newborn with asphyxia, a patient with hypoglycemia, a patient who suffered from asphyxia by an accident 10 years before, a patient with carbon monoxide poisoning at an acute stage, a patient who had carbon monoxide poisoning 10 years before, a patient with diffuse cerebral ischemic changes, a patient with cerebral edema around metastatic tumor, a patient with respiration brain, a patient with neurological sequelae after cerebral contusion, a patient who had an operation to excise right parietal lobe artery malformation, and a patient who was shooted by a machine gun and had a lead in the brain for 34 years. (Tsunoda, M.)

Asymmetry in power-law magnitude correlations.

Science.gov (United States)

Podobnik, Boris; Horvatić, Davor; Tenenbaum, Joel N; Stanley, H Eugene

2009-07-01

Time series of increments can be created in a number of different ways from a variety of physical phenomena. For example, in the phenomenon of volatility clustering-well-known in finance-magnitudes of adjacent increments are correlated. Moreover, in some time series, magnitude correlations display asymmetry with respect to an increment's sign: the magnitude of |x_{i}| depends on the sign of the previous increment x_{i-1} . Here we define a model-independent test to measure the statistical significance of any observed asymmetry. We propose a simple stochastic process characterized by a an asymmetry parameter lambda and a method for estimating lambda . We illustrate both the test and process by analyzing physiological data.

Why sex hormones matter for neuroscience: A very short review on sex, sex hormones, and functional brain asymmetries.

Science.gov (United States)

Hausmann, Markus

2017-01-02

Biological sex and sex hormones are known to affect functional cerebral asymmetries (FCAs). Men are generally more lateralized than women. The effect size of this sex difference is small but robust. Some of the inconsistencies in the literature may be explained by sex-related hormonal differences. Most studies focusing on neuromodulatory properties of sex hormones on FCAs have investigated women during the menstrual cycle. Although contradictions exist, these studies have typically shown that levels of estradiol and/or progesterone correlate with the degree of FCAs, suggesting that sex differences in FCAs partially depend on hormonal state and day of testing. The results indicate that FCAs are not fixed but are hormone dependent, and as such they can dynamically change within relatively short periods throughout life. Many issues raised in this Mini-Review refer not only to FCAs but also to other aspects of functional brain organization, such as functional connectivity within and between the cerebral hemispheres. Our understanding of sex differences in brain and behavior as well as their clinical relevance will improve significantly if more studies routinely take sex and sex hormones into account. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Leptogenesis and gravity: Baryon asymmetry without decays

Energy Technology Data Exchange (ETDEWEB)

McDonald, J.I., E-mail: pymcdonald@swansea.ac.uk; Shore, G.M., E-mail: g.m.shore@swansea.ac.uk

2017-03-10

A popular class of theories attributes the matter-antimatter asymmetry of the Universe to CP-violating decays of super-heavy BSM particles in the Early Universe. Recently, we discovered a new source of leptogenesis in these models, namely that the same Yukawa phases which provide the CP violation for decays, combined with curved-spacetime loop effects, lead to an entirely new gravitational mechanism for generating an asymmetry, driven by the expansion of the Universe and independent of the departure of the heavy particles from equilibrium. In this Letter, we build on previous work by analysing the full Boltzmann equation, exploring the full parameter space of the theory and studying the time-evolution of the asymmetry. Remarkably, we find regions of parameter space where decays play no part at all, and where the baryon asymmetry of the Universe is determined solely by gravitational effects.

Overview of Four Functional Classification Systems Commonly Used in Cerebral Palsy

Directory of Open Access Journals (Sweden)

Andrea Paulson

2017-04-01

Full Text Available Cerebral palsy (CP is the most common physical disability in childhood. CP comprises a heterogeneous group of disorders that can result in spasticity, dystonia, muscle contractures, weakness and coordination difficulty that ultimately affects the ability to control movements. Traditionally, CP has been classified using a combination of the motor type and the topographical distribution, as well as subjective severity level. Imprecise terms such as these tell very little about what a person is able to do functionally and can impair clear communication between providers. More recently, classification systems have been created employing a simple ordinal grading system of functional performance. These systems allow a more precise discussion between providers, as well as better subject stratification for research. The goal of this review is to describe four common functional classification systems for cerebral palsy: the Gross Motor Function Classification System (GMFCS, the Manual Ability Classification System (MACS, the Communication Function Classification System (CFCS, and the Eating and Drinking Ability Classification System (EDACS. These measures are all standardized, reliable, and complementary to one another.

Inclusive asymmetries

International Nuclear Information System (INIS)

Peterson, E.A.

1977-01-01

The polarized proton beam was used to measure left-right asymmetries for the reactions p + p → p, K +- , π +- + anything and also some information on the reaction p + n → p, K +- , π + + anything are presented. The incident momentum is 11.8 GeV/c. The data are preliminary. Six references

A brain stress test: Cerebral perfusion during memory encoding in mild cognitive impairment.

Science.gov (United States)

Xie, Long; Dolui, Sudipto; Das, Sandhitsu R; Stockbower, Grace E; Daffner, Molly; Rao, Hengyi; Yushkevich, Paul A; Detre, John A; Wolk, David A

2016-01-01

Arterial spin labeled perfusion magnetic resonance imaging (ASL MRI) provides non-invasive quantification of cerebral blood flow, which can be used as a biomarker of brain function due to the tight coupling between cerebral blood flow (CBF) and brain metabolism. A growing body of literature suggests that regional CBF is altered in neurodegenerative diseases. Here we examined ASL MRI CBF in subjects with amnestic mild cognitive impairment (n = 65) and cognitively normal healthy controls (n = 62), both at rest and during performance of a memory-encoding task. As compared to rest, task-enhanced ASL MRI improved group discrimination, which supports the notion that physiologic measures during a cognitive challenge, or "stress test", may increase the ability to detect subtle functional changes in early disease stages. Further, logistic regression analysis demonstrated that ASL MRI and concomitantly acquired structural MRI provide complementary information of disease status. The current findings support the potential utility of task-enhanced ASL MRI as a biomarker in early Alzheimer's disease.

Infant Positioning, Baby Gear Use, and Cranial Asymmetry.

Science.gov (United States)

Zachry, Anne H; Nolan, Vikki G; Hand, Sarah B; Klemm, Susan A

2017-12-01

Objectives This study aimed to identify predictors of cranial asymmetry. We hypothesize that among infants diagnosed with cranial asymmetry in the sampled region, there is an association between exposure to more time in baby gear and less awake time in prone and side-lying than in infants who do not present with this condition. Methods The study employed a cross sectional survey of caregivers of typically developing infants and infants diagnosed with cranial asymmetry. Results A mutivariable model reveals that caregivers of children who are diagnosed with cranial asymmetry report their children spending significantly less time in prone play than those children without a diagnosis of cranial asymmetry. Side-lying and time spent in baby gear did not attain statistical significance. Conclusions for Practice Occupational therapists, physical therapists, pediatricians, nurses and other health care professionals must provide parents with early education about the importance of varying positions and prone play in infancy and address fears and concerns that may serve as barriers to providing prone playtime.

Information Asymmetry in Federations

Directory of Open Access Journals (Sweden)

Alexander Mikhailovich Libman

2014-12-01

Full Text Available The paper investigates the problems of information transmission between levels of government in a federal state. The central government in a federation typically faces serious difficulties while collecting information on economic and political situation in the regions. There are two types of problems: lack of incentives for the regions to accurately collect information and strategic manipulation of information, which are discussed in the paper along with possible solutions. In particular, overcoming information asymmetry would require the development of national parties or informal coalitions of bureaucrats and politicians of the center and of the regions, creating incentives for regional politicians to back the successful functioning of the federal level. Furthermore, the paper discusses the issue of «informal decentralization», which emerges as a result of information asymmetry, and its consequences for the functioning of a federal state, including both advantages and disadvantages. We conclude that under information asymmetry the organization of the federation will inevitably turn into an issue of permanent negotiations and bargaining between the center and the regions, which functions as the information acquisition tool for optimal allocation of authorities in a federation

Birth order and fluctuating asymmetry: a first look.

Science.gov (United States)

Lalumière, M L; Harris, G T; Rice, M E

1999-01-01

We investigated the hypothesis that maternal immunoreactivity to male-specific features of the foetus can increase developmental instability. We predicted that the participants' number of older brothers would be positively related to the fluctuating asymmetry of ten bilateral morphological traits. The participants were 40 adult male psychiatric patients and 31 adult male hospital employees. Consistent with the hypothesis, the participants' number of older brothers--but not number of older sisters, younger brothers or younger sisters--was positively associated with fluctuating asymmetry. The patients had significantly larger fluctuating asymmetry scores and tended to have more older brothers than the employees, but the positive relationship between the number of older brothers and fluctuating asymmetry was observed in both groups. PMID:10643079

Predictions of the poloidal asymmetries and transport frequencies in KSTAR

Energy Technology Data Exchange (ETDEWEB)

Bae, C., E-mail: cbae@nfri.re.kr; Lee, S. G.; Terzolo, L. [National Fusion Research Institute, Gwahak-ro, Yuseong-gu, Daejeon 305-806 (Korea, Republic of); Stacey, W. M. [Fusion Research Center, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States)

2014-01-15

The extended neoclassical rotation theory formulated in Miller flux surface geometry enables unprecedented neoclassical calculations of the poloidal asymmetries in density, rotation velocities, electrostatic potential along the flux surfaces, and of the inertial (Reynolds stress) and gyroviscous transport frequencies, which are strong functions of these asymmetries. This paper presents such calculations of the poloidal asymmetries and non-negligible inertial and gyroviscous transport frequencies in two KSTAR (Korea Superconducting Tokamak Advanced Research) [Kwon et al., Nucl. Fusion 51, 094006 (2011)] Neutral Beam Injection H-mode discharges. The in-out asymmetries in the velocities are an order of magnitude larger than their up-down asymmetries. The magnitudes of the predicted inertial and gyroviscous transport frequencies depend on the magnitudes of the density and velocity asymmetries. The neoclassically predicted density asymmetries are shown to correspond with the reported measurements in tokamaks and the predicted carbon toroidal velocities agree very well with the measurements in KSTAR.

Case-control study of six genes asymmetrically expressed in the two cerebral hemispheres: association of BAIAP2 with attention-deficit/hyperactivity disorder

DEFF Research Database (Denmark)

Ribasés, Marta; Bosch, Rosa; Hervás, Amaia

2009-01-01

BACKGROUND: Attention-deficit/hyperactivity disorder (ADHD) is a childhood-onset neuropsychiatric disease that persists into adulthood in at least 30% of patients. There is evidence suggesting that abnormal left-right brain asymmetries in ADHD patients may be involved in a variety of ADHD...... results support the participation of BAIAP2 in the continuity of ADHD across life span, at least in some of the populations analyzed, and suggest that genetic factors potentially influencing abnormal cerebral lateralization may be involved in this disorder....

Leptogenesis and gravity: Baryon asymmetry without decays

Directory of Open Access Journals (Sweden)

J.I. McDonald

2017-03-01

Full Text Available A popular class of theories attributes the matter-antimatter asymmetry of the Universe to CP-violating decays of super-heavy BSM particles in the Early Universe. Recently, we discovered a new source of leptogenesis in these models, namely that the same Yukawa phases which provide the CP violation for decays, combined with curved-spacetime loop effects, lead to an entirely new gravitational mechanism for generating an asymmetry, driven by the expansion of the Universe and independent of the departure of the heavy particles from equilibrium. In this Letter, we build on previous work by analysing the full Boltzmann equation, exploring the full parameter space of the theory and studying the time-evolution of the asymmetry. Remarkably, we find regions of parameter space where decays play no part at all, and where the baryon asymmetry of the Universe is determined solely by gravitational effects.

[Asymmetry of antennal grooming in the cockroach (Periplaneta americana)].

Science.gov (United States)

2014-07-01

The present study was conducted to determine the key features of antennal grooming of male American cockroaches in neutral circumstances. It was shown for the first time that the right antenna was cleaned significantly more often than the left one, which indicates the presence of functional asymmetry of antennal grooming in this insect species. At the same time, no statistically significant asymmetry was found for grooming of antennal bases and legs. Morphological asymmetries of antennae and legs and/or brain lateralization are the plausible sources of observed behavioral asymmetry in antennal grooming.

Kinetic asymmetries between forward and drop jump landing tasks

Directory of Open Access Journals (Sweden)

Morgana Alves de Britto

2015-12-01

Full Text Available DOI: http://dx.doi.org/10.5007/1980-0037.2015v17n6p661   Landing asymmetry is a risk factor for knee anterior cruciate ligament injury. The aim of this study was to identify kinetic asymmetries in healthy recreational athletes performing different jump-landing techniques. Twelve recreational athletes engaged in regular training underwent kinetic evaluation using two 3D force plates and were analyzed for: (a three-dimensional peak forces, (b time to peak vertical force, and (c initial phase asymmetries. All data were collected during performance of unilateral and bilateral trials of forward and drop jump tasks. Forward jump-landing tasks elicited greater kinetic asymmetry than drop-landing tasks. Regardless of jump-landing technique, the preferred leg experienced higher forces than the non-preferred leg. The initial landing phase showed more kinetic asymmetries than the later phase when peak vertical forces occur. It was concluded that when screening athletes for kinetic asymmetries that may predispose them to injury, forward jump-landing tasks and the early landing phase might show more kinetic asymmetries than drop jump-landing tasks and the late landing phase, respectively.

Unilateral condylar hyperplasia: a 3-dimensional quantification of asymmetry.

Directory of Open Access Journals (Sweden)

Tim J Verhoeven

Full Text Available PURPOSE: Objective quantifications of facial asymmetry in patients with Unilateral Condylar Hyperplasia (UCH have not yet been described in literature. The aim of this study was to objectively quantify soft-tissue asymmetry in patients with UCH and to compare the findings with a control group using a new method. MATERIAL AND METHODS: Thirty 3D photographs of patients diagnosed with UCH were compared with 30 3D photographs of healthy controls. As UCH presents particularly in the mandible, a new method was used to isolate the lower part of the face to evaluate asymmetry of this part separately. The new method was validated by two observers using 3D photographs of five patients and five controls. RESULTS: A significant difference (0.79 mm between patients and controls whole face asymmetry was found. Intra- and inter-observer differences of 0.011 mm (-0.034-0.011 and 0.017 mm (-0.007-0.042 respectively were found. These differences are irrelevant in clinical practice. CONCLUSION: After objective quantification, a significant difference was identified in soft-tissue asymmetry between patients with UCH and controls. The method used to isolate mandibular asymmetry was found to be valid and a suitable tool to evaluate facial asymmetry.

Measurement of Z0 lepton coupling asymmetries

International Nuclear Information System (INIS)

Smy, M.B.

1997-07-01

Polarized Z 0 's from e + e - collisions at the SLAC Linear Collider (SLC) have been used to determine the asymmetry parameters A e , A μ and A τ from the leptonic decay channels. This is the first direct measurement of A μ . The data have been gathered by the SLC Large Detector (SLD) with the electron polarization averaging 63% during the 1993 data taking period and 77% in 1994-95. A maximum likelihood procedure as well as cross section asymmetries was used to measure the asymmetry parameters from the differential cross sections for equal luminosities of left- and right-handed electron beams. The polarization-dependent muon-pair distributions give A μ = 0.102 ±0.034 and the tau-pairs give A τ = 0.195 ±0.034. The initial state electronic couplings in all three leptonic channels as well as the final state angular distribution in the e + e - final state measure A e to be A e = 0.152±0.012. Assuming lepton universality and defining a global leptonic asymmetry parameter A e-μ-τ = 0.151±0.011. This global leptonic asymmetry value translates directly into sin 2 θ W eff =0.2310±0.0014 at the Z 0 pole

Measuring Asymmetry in Insect-Plant Networks

Energy Technology Data Exchange (ETDEWEB)

Cruz, Claudia P T [Programa de Pos-Graduacao em Fisica, Universidade Federal do Rio Grande do Norte, UFRN - Campus Universitario, Lagoa Nova, CEP 59078 972, Natal, RN (Brazil); De Almeida, Adriana M [Departamento de Botanica, Ecologia e Zoologia, Centro de Biociencias, Universidade Federal do Rio Grande do Norte, UFRN - Campus Universitario, Lagoa Nova, CEP 59078 972, Natal, RN (Brazil); Corso, Gilberto, E-mail: claudia@dfte.ufrn.br, E-mail: adrianam@ufrn.br, E-mail: corso@cb.ufrn.br [Departamento de Biofisica e Farmacologia, Centro de Biociencias, Universidade Federal do Rio Grande do Norte, UFRN - Campus Universitario, Lagoa Nova, CEP 59078 972, Natal, RN (Brazil)

2011-03-01

In this work we focus on interaction networks between insects and plants and in the characterization of insect plant asymmetry, an important issue in coevolution and evolutionary biology. We analyze in particular the asymmetry in the interaction matrix of animals (herbivorous insects) and plants (food resource for the insects). Instead of driving our attention to the interaction matrix itself we derive two networks associated to the bipartite network: the animal network, D{sub 1}, and the plant network, D{sub 2}. These networks are constructed according to the following recipe: two animal species are linked once if they interact with the same plant. In a similar way, in the plant network, two plants are linked if they interact with the same animal. To explore the asymmetry between D{sub 2} and D{sub 1} we test for a set of 23 networks from the ecologic literature networks: the difference in size, {Delta}L, clustering coefficient difference, {Delta}C, and mean connectivity difference, {Delta}. We used a nonparametric statistical test to check the differences in {Delta}L, {Delta}C and {Delta}. Our results indicate that {Delta}L and {Delta} show a significative asymmetry.

Complementary and Integrative Medicine

Science.gov (United States)

... medical treatments that are not part of mainstream medicine. When you are using these types of care, it may be called complementary, integrative, or alternative medicine. Complementary medicine is used together with mainstream medical ...

Regional cerebral glucose metabolism in frontotemporal dementia: a study with FDG PET

Energy Technology Data Exchange (ETDEWEB)

Cho, S. S.; Jeong, J.; Kang, S. J.; Na, D. L.; Choe, Y. S.; Lee, K. H.; Choi, Y.; Kim, B. T.; Kim, S. E. [Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

2002-07-01

Frontotemporal dementia (FTD) is a common cause of presenile dementia. We investigated the regional cerebral glucose metabolic impairments in patients with FTD using FDG PET. We analysed the regional metabolic patterns on FDG PET images obtained from 30 patients with FTD and age- and sex-matched 15 patients with Alzheimers disease (AD) and 11 healthy subjects using SPM99. We also compared the inter-hemispheric metabolic asymmetry among the three groups by counting the total metabolic activity of each hemisphere and computing asymmetry index (AL) between hemispheres. The hypometabolic brain regions in FTD patients compared with healthy controls were as follows: superior middle and medial frontal lobules, superior and middle temporal lobules, anterior and posterior cingulate gyri, uncus, insula, lateral globus pallidus and thalamus. The regions with decreased metabolism in FTD patients compared with AD patients were as follows: superior, inferior and medial frontal lobules, anterior cingulate gyrus, and caudate nucleus. Twenty-five (83%) out of the 30 FTD patients had AI values that was beyond the 95% confidence interval of the AI values obtained from healthy controls; 10 patients had hypometabolism more severe on the right and 15 patients had the opposite pattern. In comparison, 10 (67%) out of the 15 AD patients had asymmetric metabolism. Our SPM analysis of FDG PET revealed additional areas of decreased metabolism in FTD patients compared with prior studies using the ROI method, involving frontal, temporal, cingulate gyrus, corpus callosum, uncus, insula, and some subcortical areas. The inter-hemispheric metabolic asymmetry was common in FTD patients, which can be another metabolic feature that helps differentiate FTD from AD.

Regional cerebral glucose metabolism in frontotemporal dementia: a study with FDG PET

International Nuclear Information System (INIS)

Cho, S. S.; Jeong, J.; Kang, S. J.; Na, D. L.; Choe, Y. S.; Lee, K. H.; Choi, Y.; Kim, B. T.; Kim, S. E.

2002-01-01

Frontotemporal dementia (FTD) is a common cause of presenile dementia. We investigated the regional cerebral glucose metabolic impairments in patients with FTD using FDG PET. We analysed the regional metabolic patterns on FDG PET images obtained from 30 patients with FTD and age- and sex-matched 15 patients with Alzheimers disease (AD) and 11 healthy subjects using SPM99. We also compared the inter-hemispheric metabolic asymmetry among the three groups by counting the total metabolic activity of each hemisphere and computing asymmetry index (AL) between hemispheres. The hypometabolic brain regions in FTD patients compared with healthy controls were as follows: superior middle and medial frontal lobules, superior and middle temporal lobules, anterior and posterior cingulate gyri, uncus, insula, lateral globus pallidus and thalamus. The regions with decreased metabolism in FTD patients compared with AD patients were as follows: superior, inferior and medial frontal lobules, anterior cingulate gyrus, and caudate nucleus. Twenty-five (83%) out of the 30 FTD patients had AI values that was beyond the 95% confidence interval of the AI values obtained from healthy controls; 10 patients had hypometabolism more severe on the right and 15 patients had the opposite pattern. In comparison, 10 (67%) out of the 15 AD patients had asymmetric metabolism. Our SPM analysis of FDG PET revealed additional areas of decreased metabolism in FTD patients compared with prior studies using the ROI method, involving frontal, temporal, cingulate gyrus, corpus callosum, uncus, insula, and some subcortical areas. The inter-hemispheric metabolic asymmetry was common in FTD patients, which can be another metabolic feature that helps differentiate FTD from AD

Age and Practice Effects on Inter-manual Performance Asymmetry

Directory of Open Access Journals (Sweden)

Karen L Francis

2015-01-01

Full Text Available Manual dexterity declines with increasing age however, the way in which inter-manual asymmetry responds to aging is unclear. Our purpose was to determine the effect of age and practice on inter-manual performance asymmetry in an isometric force pinch line tracing task that varied in difficulty within segments. Thirty right handed participants, 5 males and 5 females in each of three age groups, young (Y20, young-old (O70, and old-old (O80, practiced an isometric force pinch task for 10 trials with each hand on each of five consecutive days. Inter-manual performance asymmetry of the right and left hands was analyzed with a repeated measures ANOVA of asymmetry with age groups, practice, task difficulty, and hand as factors. The within-individual magnitude of asymmetry was also analyzed with a repeated measures ANOVA of manual asymmetry calculated as an asymmetry index (AI. Post hoc pair-wise comparisons were performed when significance was found. We observed no inter-manual performance asymmetry on this isometric tracing task among any of the age groups, either in the hand performance differences or in the magnitude of the asymmetry index (AI. Age and practice interacted in terms of manual performance: the Y20 and O70 group improved accuracy and task time across the five days of practice but the O80 group did not. However, practice did not differentially affect the AI for accuracy or task time for any group. Accuracy of performance of the two hands was differentially affected by practice. All age groups exhibited poorer performance and larger AIs on the most difficult segments of the task (3 and 6 and this did not change with practice.

Comparison of acetazolamide-enhanced brain SPECT using Tc-99m ECD with cerebral angiography in patients with cerebrovascular disease

International Nuclear Information System (INIS)

Choi, Y. Y.; Moon, D. H.; Ryu, J. S.; Yang, S. H.; Lee, H. K.; Lee, J. H.; Kim, J. S.; Kim, K. A.

1997-01-01

Cerebral vascular reserve can be assessed by development of collateral channels (DCC) on cerebral angiography(CA) or vasoreactivity (VR) on acetazolamide-enhanced brain SPECT (ACZ-SPECT). The purpose of this study was to compare Tc-99m ECD ACZ-SPECT with CA in the evaluation of vascular reserve in patients (pts) with cerebrovascular disease(CVD). Twenty seven patients with CVD, including TIA (n=13), infarction (n=11) and asymptomatic pts (AS, n=3), underwent CA and ACZ-SPECT. Basal and ACZ-SPECT was obtained consecutively, and image subtraction was performed. On CA, degree of DCC was scored 0-3 (0: normal, 3: poor) according to parenchymal staining on delayed film. In ACZ-SPECT, decrease of VR was graded 0-3 (0: normal, 3: more than 30% decrease). The correlation between degree of stenosis, DCC and VR were analyzed. 1) Variable degree of VR or DCC was observed in totally occluded or stenotic cerebral arterial territories. 2) In arterial territories with poor DCC, ACZ-SPECT showed poor VR. However, in 5 out of 11 TIA or AS with good DCC, poor VR was observed. These data suggests that 1) cerebral hemodynamic status cannot be assessed by the degree of stenosis on CA alone. 2) DCC may overestimate the cerebral vascular reserve in patients with TIA or AS. 3) ACZ-SPECT plays a complementary role to CA for evaluation of cerebral hemodynamic status in pts with CVD

United Cerebral Palsy

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... your local affiliate Find your local affiliate United Cerebral Palsy United Cerebral Palsy (UCP) is a trusted resource for individuals with Cerebral Palsy and other disabilities and their networks. Individuals with ...

Audiometric asymmetry and tinnitus laterality.

Science.gov (United States)

Tsai, Betty S; Sweetow, Robert W; Cheung, Steven W

2012-05-01

To identify an optimal audiometric asymmetry index for predicting tinnitus laterality. Retrospective medical record review. Data from adult tinnitus patients (80 men and 44 women) were extracted for demographic, audiometric, tinnitus laterality, and related information. The main measures were sensitivity, specificity, positive predictive value (PPV), and receiver operating characteristic (ROC) curves. Three audiometric asymmetry indices were constructed using one, two, or three frequency elements to compute the average interaural threshold difference (aITD). Tinnitus laterality predictive performance of a particular index was assessed by increasing the cutoff or minimum magnitude of the aITD from 10 to 35 dB in 5-dB steps to determine its ROC curve. Single frequency index performance was inferior to the other two (P .05). Two adjoining frequency elements with aITD ≥ 15 dB performed optimally for predicting tinnitus laterality (sensitivity = 0.59, specificity = 0.71, and PPV = 0.76). Absolute and relative magnitudes of hearing loss in the poorer ear were uncorrelated with tinnitus distress. An optimal audiometric asymmetry index to predict tinnitus laterality is one whereby 15 dB is the minimum aITD of two adjoining frequencies, inclusive of the maximal ITD. Tinnitus laterality dependency on magnitude of interaural asymmetry may inform design and interpretation of neuroimaging studies. Monaural acoustic tinnitus therapy may be an initial consideration for asymmetric hearing loss meeting the criterion of aITD ≥ 15 dB. Copyright © 2012 The American Laryngological, Rhinological, and Otological Society, Inc.

Subcycle dynamics of Coulomb asymmetry in strong elliptical laser fields.

Science.gov (United States)

Li, Min; Liu, Yunquan; Liu, Hong; Ning, Qicheng; Fu, Libin; Liu, Jie; Deng, Yongkai; Wu, Chengyin; Peng, Liang-You; Peng, Liangyou; Gong, Qihuang

2013-07-12

We measure photoelectron angular distributions of noble gases in intense elliptically polarized laser fields, which indicate strong structure-dependent Coulomb asymmetry. Using a dedicated semiclassical model, we have disentangled the contribution of direct ionization and multiple forward scattering on Coulomb asymmetry in elliptical laser fields. Our theory quantifies the roles of the ionic potential and initial transverse momentum on Coulomb asymmetry, proving that the small lobes of asymmetry are induced by direct ionization and the strong asymmetry is induced by multiple forward scattering in the ionic potential. Both processes are distorted by the Coulomb force acting on the electrons after tunneling. Lowering the ionization potential, the relative contribution of direct ionization on Coulomb asymmetry substantially decreases and Coulomb focusing on multiple rescattering is more important. We do not observe evident initial longitudinal momentum spread at the tunnel exit according to our simulation.

Special Section: Complementary and Alternative Medicine (CAM):Quiz on Complementary and Alternative Medicine

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... Special Section CAM Quiz on Complementary and Alternative Medicine Past Issues / Winter 2009 Table of Contents For ... low back pain. True False Complementary and alternative medicine (CAM) includes: Meditation Chiropractic Use of natural products, ...

Complementary and Alternative Medicine

Science.gov (United States)

... for Educators Search English Español Complementary and Alternative Medicine KidsHealth / For Teens / Complementary and Alternative Medicine What's ... a replacement. How Is CAM Different From Conventional Medicine? Conventional medicine is based on scientific knowledge of ...

Neocortical synaptophysin asymmetry and behavioral lateralization in chimpanzees (Pan troglodytes)

DEFF Research Database (Denmark)

Sherwood, Chet C; Duka, Tetyana; Stimpson, Cheryl D

2010-01-01

Although behavioral lateralization is known to correlate with certain aspects of brain asymmetry in primates, there are limited data concerning hemispheric biases in the microstructure of the neocortex. In the present study, we investigated whether there is asymmetry in synaptophysin-immunoreacti......Although behavioral lateralization is known to correlate with certain aspects of brain asymmetry in primates, there are limited data concerning hemispheric biases in the microstructure of the neocortex. In the present study, we investigated whether there is asymmetry in synaptophysin...... density. In contrast, puncta densities were symmetrical in right-handed chimpanzees. These findings support the conclusion that synapse asymmetry is modulated by lateralization of skilled motor behavior in chimpanzees....

Frontal sinus asymmetry: Is it an effect of cranial asymmetry? X-ray analysis of 469 normal adult human frontal sinus

Directory of Open Access Journals (Sweden)

Ayhan Kanat

2015-01-01

Full Text Available Background and Aims: There is no study in the literature that investigates an asymmetric morphological feature of the frontal sinus (FS. Materials and Methods: Four hundred and sixty-nine consecutive direct X-rays of FSs were analyzed for the asymmetry between the right and left sides. When an asymmetry in the height and contour of the FS existed, this difference was quantified. Results: Of the 469 patients, X-rays of 402 patients (85.7%, there was an asymmetry between right and left sides of the FS. Of these 235 (50.1% were dominant on the left side, whereas 167 (35.6% were dominant on the right, the sinuses of remaining 67 patients (14.3% was symmetric. Statistical Analysis: The comparisons between parameters were performed using Wilkinson signed rank test. The relationship between handedness and sinus asymmetry was also examined by two proportions test. There is statistically significant difference between the dominance of left and right FS. Conclusions: Hemispheric dominance may have some effect (s of on sinus asymmetry of the human cranium. Surgeons sometimes enter the cranium through the FS and knowledge of asymmetric FS is important to minimize surgical complications.

North-South asymmetry of interplanetary plasma and solar parameters

International Nuclear Information System (INIS)

El-Borie, M. A.

2001-01-01

Data of interplanetary plasma (field magnitude, solar wind speed, ion plasma density and temperature) and solar parameters (sunspot number, solar radio flux, and geomagnetic index) over the period 1965-1991, have been used to examine the asymmetry between the solar field north and south of the heliospheric current sheet (HCS). The dependence of N-S asymmetry of field magnitude (B) upon the interplanetary solar polarities is statistically insignificant. There is no clear indication for the presence of N-S asymmetry in the grand-average field magnitude over the solar cycles. During the period 1981-89 (qA<0; negative solar polarity state), the solar plasma was more dense and cooler south of the HCS than north of it. The solar flux component of toward field vector is larger in magnitude than those of away field vector during the qA<0 epoch, and no asymmetry observed in the qA<0 epoch. Furthermore, the sign of the N-S asymmetry in the solar activity depends positively upon the solar polarity state. In addition, it was studied the N-S asymmetry of solar parameters near the HCS, throughout the periods of northern and southern hemispheres were more active than the other. Some asymmetries (with respect to the HCS) in plasma parameters existed during the periods of southern hemisphere predominance

Sex-dependent alterations in resting-state cerebral blood flow, amplitude of low-frequency fluctuations and their coupling relationship in schizophrenia.

Science.gov (United States)

Ma, Xiaomei; Wang, Di; Zhou, Yujing; Zhuo, Chuanjun; Qin, Wen; Zhu, Jiajia; Yu, Chunshui

2016-04-01

blood flow-amplitude of low-frequency fluctuations couplings compared with those of healthy females. The alterations in the relative cerebral blood flow and amplitude of low-frequency fluctuations in schizophrenia are sex-specific, which should be considered in future neuroimaging studies. The relative cerebral blood flow and amplitude of low-frequency fluctuations have different sensitivity in detecting changes in neuronal activity in schizophrenia and can provide complementary information. © The Royal Australian and New Zealand College of Psychiatrists 2015.

Do Board Characteristics Affect Information Asymmetry?

OpenAIRE

Sougné, Danielle; Laouti, Mhamed; Ajina, Aymen

2013-01-01

In this paper, we investigate the empirical relationship between corporate governance and information asymmetry across a range of French firms. Based on a cross-sectional analysis, our study of the empirical relationship between corporate governance and information asymmetry involved 160 companies over the years 2008-2010. Mechanisms of corporate governance include the characteristics of the board of directors. Our results seem to indicate a significant relationship between certain mechani...

Photon asymmetry from radiative muon capture on 40Ca

International Nuclear Information System (INIS)

Larabee, A.J.; Burnham, R.A.; Gorringe, T.P.; Hasinoff, M.D.; Horvath, D.; Noble, A.J.; Pouladdej, A.; Virtue, C.J.; Azuelos, G.; Robertson, B.C.; Wright, D.H.

1989-01-01

The photon asymmetry (α γ) for 40 Ca has been measured at TRIUMF using the muon spin-rotation technique. From the asymmetry measurement, the value of the pseudoscalar coupling constant, g p , can be obtained. A total of 5500 clean photon events were collected. The preliminary value found for the photon asymmetry of 40 Ca is 1.00 ± 0.23

Study on parallel-channel asymmetry in supercritical flow instability experiment

International Nuclear Information System (INIS)

Xiong Ting; Yu Junchong; Yan Xiao; Huang Yanping; Xiao Zejun; Huang Shanfang

2013-01-01

Due to the urgent need for experimental study on supercritical water flow instability, the parallel-channel asymmetry which determines the feasibility of such experiments was studied with the experimental and numerical results in parallel dual channel. The evolution of flow rates in the experiments was analyzed, and the steady-state characteristics as well as transient characteristics of the system were obtained by self-developed numerical code. The results show that the asymmetry of the parallel dual channel would reduce the feasibility of experiments. The asymmetry of flow rates is aroused by geometrical asymmetry. Due to the property variation characteristics of supercritical water, the flow rate asymmetry is enlarged while rising beyond the pseudo critical point. The extent of flow rate asymmetry is affected by the bulk temperature and total flow rate; therefore the experimental feasibility can be enhanced by reducing the total flow rate. (authors)

Measurement of cerebral blood flow with 133Xe inhalation and dynamic single photon emission computer tomography. Normal values

International Nuclear Information System (INIS)

Rootwelt, Kjell; Dybevold, Synnoeve; Nyberg-Hansen, Rolf; Russell, David

1986-01-01

Cerebral blood flow was studied by 133 Xe inhalation tomography in 25 healthy subjects. Mean age was 41 years and range 23-66 years. Mean hemispheric CBF at rest was 59.8 ml/100 g/min, and cerebellar flow 60.8 ml/100 g/min. The distribution of CBF values was skewed and approximated a log normal distribution. Estimated lower and upper normal reference range limits calculated as mean (log) = - 2 S.D. (log) were 47-74 ml/100 g/min. Women had approximately 5 ml/100 g/min higher CBF values than men, corresponding to the difference in hematocrit. Neither in men or women was there any tendency to age dependent reduction or increase in flow. In both sexes hemispheric regional CBF (rCBF) was asymmetric with higher flow values in the right cerebral hemisphere; particularly in the anterior distribution territory of the middle cerebral artery. Emotional activation as a consequence of the study conditions is assumed to be the cause of this observed asymmetry. Cerebellar flow was not assymetric. No significant difference in cerebellar or hemispheric CBF was found when a second study followed the first by 3-15 months, PCO 2 correction of flow improved reproducibility. Acetazolamide responses are reported. (author)

Malaria cerebral Cerebral malaria

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Carlos Hugo Zapata Zapata

2003-03-01

Full Text Available La malaria Cerebral (MC es la complicación más frecuente de la malaria por P. falciparum; aproximadamente el 90% de las personas que la han padecido se recuperan completamente sin secuelas neurológicas. Aún no se conoce con claridad su patogénesis pero se han postulado cuatro hipótesis o mecanismos posibles: 1 citoadherencia y secuestro de glóbulos rojos parasitados en la microvasculatura cerebral; 2 formación de rosetas y aglutinación de glóbulos rojos parasitados; 3 producción de citoquinas y activación de segundos mensajeros y, 4 apertura de la barrera hematoencefálica. Sin embargo, queda un interrogante sin resolver aún: ¿qué proceso se lleva a cabo para que el parásito, desde el espacio microvascular, pueda interferir transitoriamente con la función cerebral? Recientemente se ha utilizado el precursor de la proteína b-Amiloide como un marcador de daño neuronal en MC; este precursor será de gran ayuda en futuras investigaciones realizadas en nuestro medio que aporten información para comprender la patogénesis de la MC. Is the most common complication of P. falciparum malaria; nearly 90% of people who have suffered CM can recover without neurological problems. Currently there are four hypotheses that explain pathogenesis of CM: cytoadherence and sequestering of parasitized red blood cells to cerebral capillaries; rosette formation and parasitized red blood cells agglutination; production of cytokines and activation of second messengers and opening of the blood-brain barrier. However the main question remains to be answered; how the host-parasite interaction in the vascular space interferes transiently with cerebral function? Recently, the beta amyloid precursor peptide has been employed as marker of neural injury in CM. It is expected that the beta amyloid precursor peptide will help to understand the pathogenesis of CM in complicated patients of endemic areas of Colombia.

Frontal EEG asymmetry as a moderator and mediator of emotion.

Science.gov (United States)

Coan, James A; Allen, John J B

2004-10-01

Frontal EEG asymmetry appears to serve as (1) an individual difference variable related to emotional responding and emotional disorders, and (2) a state-dependent concomitant of emotional responding. Such findings, highlighted in this review, suggest that frontal EEG asymmetry may serve as both a moderator and a mediator of emotion- and motivation-related constructs. Unequivocal evidence supporting frontal EEG asymmetry as a moderator and/or mediator of emotion is lacking, as insufficient attention has been given to analyzing the frontal EEG asymmetries in terms of moderators and mediators. The present report reviews the frontal EEG asymmetry literature from the framework of moderators and mediators, and overviews data analytic strategies that would support claims of moderation and mediation.

Lepton polarization asymmetries in rare semi-tauonic b → s exclusive decays at FCC-ee

Energy Technology Data Exchange (ETDEWEB)

Kamenik, J.F. [Jozef Stefan Institute, Ljubljana (Slovenia); University of Ljubljana, Faculty of Mathematics and Physics, Ljubljana (Slovenia); Monteil, S. [Universite Clermont Auvergne, CNRS/IN2P3, LPC, Clermont-Ferrand (France); Semkiv, A. [Universite Clermont Auvergne, CNRS/IN2P3, LPC, Clermont-Ferrand (France); Taras Shevchenko National University of Kyiv, Kyiv (Ukraine); Silva, L.V. [Jozef Stefan Institute, Ljubljana (Slovenia)

2017-10-15

We consider measurements of exclusive rare semi-tauonic b-hadron decays, mediated by the b → sτ{sup +}τ{sup -} transition, at a future high-energy circular electron-positron collider (FCC-ee). We argue that the high boosts of b-hadrons originating from on-shell Z boson decays allow for a full reconstruction of the decay kinematics in hadronic τ decay modes (up to discrete ambiguities). This, together with the potentially large statistics of Z → b anti b, opens the door for the experimental determination of τ polarizations in these rare b-hadron decays. In the light of the current experimental situation on lepton flavor universality in rare semileptonic B decays, we discuss the complementary short-distance physics information carried by the τ polarizations and suggest suitable theoretically clean observables in the form of single- and double-τ polarization asymmetries. (orig.)

Temporal Lobe White Matter Asymmetry and Language Laterality in Epilepsy Patients

Science.gov (United States)

Ellmore, Timothy M.; Beauchamp, Michael S.; Breier, Joshua I.; Slater, Jeremy D.; Kalamangalam, Giridhar P.; O’Neill, Thomas J.; Disano, Michael A.; Tandon, Nitin

2009-01-01

Recent studies using diffusion tensor imaging (DTI) have advanced our knowledge of the organization of white matter subserving language function. It remains unclear, however, how DTI may be used to predict accurately a key feature of language organization: its asymmetric representation in one cerebral hemisphere. In this study of epilepsy patients with unambiguous lateralization on Wada testing (19 left and 4 right lateralized subjects; no bilateral subjects), the predictive value of DTI for classifying the dominant hemisphere for language was assessed relative to the existing standard - the intra-carotid Amytal (Wada) procedure. Our specific hypothesis is that language laterality in both unilateral left- and right-hemisphere language dominant subjects may be predicted by hemispheric asymmetry in the relative density of three white matter pathways terminating in the temporal lobe implicated in different aspects of language function: the arcuate (AF), uncinate (UF), and inferior longitudinal fasciculi (ILF). Laterality indices computed from asymmetry of high anisotropy AF pathways, but not the other pathways, classified the majority (19 of 23) of patients using the Wada results as the standard. A logistic regression model incorporating information from DTI of the AF, fMRI activity in Broca’s area, and handedness was able to classify 22 of 23 (95.6%) patients correctly according to their Wada score. We conclude that evaluation of highly anisotropic components of the AF alone has significant predictive power for determining language laterality, and that this markedly asymmetric distribution in the dominant hemisphere may reflect enhanced connectivity between frontal and temporal sites to support fluent language processes. Given the small sample reported in this preliminary study, future research should assess this method on a larger group of patients, including subjects with bihemispheric dominance. PMID:19874899

Cerebral Palsy (For Teens)

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... Staying Safe Videos for Educators Search English Español Cerebral Palsy KidsHealth / For Teens / Cerebral Palsy What's in this ... do just what everyone else does. What Is Cerebral Palsy? Cerebral palsy (CP) is a disorder of the ...

fMRI-vs-MEG evaluation of post-stroke interhemispheric asymmetries in primary sensorimotor hand areas.

Science.gov (United States)

Altamura, Claudia; Torquati, Kahtya; Zappasodi, Filippo; Ferretti, Antonio; Pizzella, Vittorio; Tibuzzi, Francesco; Vernieri, Fabrizio; Pasqualetti, Patrizio; Landi, Doriana; Del Gratta, Cosimo; Romani, Gian-Luca; Maria Rossini, Paolo; Tecchio, Franca

2007-04-01

Growing evidence emphasizes a positive role of brain ipsilesional (IL) reorganization in stroke patients with partial recovery. Ten patients affected by a monohemispheric stroke in the middle cerebral artery territory underwent functional magnetic resonance (fMRI) and magnetoencephalography (MEG) evaluation of the primary sensory (S1) activation via the same paradigm (median nerve galvanic stimulation). Four patients did not present S1 fMRI activation [Rossini, P.M., Altamura, C., Ferretti, A., Vernieri, F., Zappasodi, F., Caulo, M., Pizzella, V., Del Gratta, C., Romani, G.L., Tecchio, F., 2004. Does cerebrovascular disease affect the coupling between neuronal activity and local haemodynamics? Brain 127, 99-110], although inclusion criteria required bilateral identifiable MEG responses. Mean Euclidean distance between fMRI and MEG S1 activation Talairach coordinates was 10.1+/-2.9 mm, with a 3D intra-class correlation (ICC) coefficient of 0.986. Interhemispheric asymmetries, evaluated by an MEG procedure independent of Talairach transformation, were outside or at the boundaries of reference ranges in 6 patients. In 3 of them, the IL activation presented medial or lateral shift with respect to the omega-shaped post-rolandic area while in the other 3, IL areas were outside the peri-rolandic region. In conclusion, despite dissociated intensity, the MEG and fMRI activations displayed good spatial consistency in stroke patients, thus confirming excessive interhemispheric asymmetries as a suitable indicator of unusual recruitments in the ipsilesional hemisphere, within or outside the peri-rolandic region.

Transmuted Complementary Weibull Geometric Distribution

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Ahmed Z. A…fify

2014-12-01

Full Text Available This paper provides a new generalization of the complementary Weibull geometric distribution that introduced by Tojeiro et al. (2014, using the quadratic rank transmutation map studied by Shaw and Buckley (2007. The new distribution is referred to as transmuted complementary Weibull geometric distribution (TCWGD. The TCWG distribution includes as special cases the complementary Weibull geometric distribution (CWGD, complementary exponential geometric distribution(CEGD,Weibull distribution (WD and exponential distribution (ED. Various structural properties of the new distribution including moments, quantiles, moment generating function and RØnyi entropy of the subject distribution are derived. We proposed the method of maximum likelihood for estimating the model parameters and obtain the observed information matrix. A real data set are used to compare the ‡exibility of the transmuted version versus the complementary Weibull geometric distribution.

Mercury exposure may influence fluctuating asymmetry in waterbirds.

Science.gov (United States)

Herring, Garth; Eagles-Smith, Collin A; Ackerman, Joshua T

2017-06-01

Variation in avian bilateral symmetry can be an indicator of developmental instability in response to a variety of stressors, including environmental contaminants. The authors used composite measures of fluctuating asymmetry to examine the influence of mercury concentrations in 2 tissues on fluctuating asymmetry within 4 waterbird species. Fluctuating asymmetry increased with mercury concentrations in whole blood and breast feathers of Forster's terns (Sterna forsteri), a species with elevated mercury concentrations. Specifically, fluctuating asymmetry in rectrix feather 1 was the most strongly correlated structural variable of those tested (wing chord, tarsus, primary feather 10, rectrix feather 6) with mercury concentrations in Forster's terns. However, for American avocets (Recurvirostra americana), black-necked stilts (Himantopus mexicanus), and Caspian terns (Hydroprogne caspia), the authors found no relationship between fluctuating asymmetry and either whole-blood or breast feather mercury concentrations, even though these species had moderate to elevated mercury exposure. The results indicate that mercury contamination may act as an environmental stressor during development and feather growth and contribute to fluctuating asymmetry of some species of highly contaminated waterbirds. Environ Toxicol Chem 2017;36:1599-1605. Published 2016 Wiley Periodicals Inc. on behalf of SETAC. This article is a US government work and, as such, is in the public domain in the United States of America. Published 2016 Wiley Periodicals Inc. on behalf of SETAC. This article is a US government work and, as such, is in the public domain in the United States of America.

Prediction of Gap Asymmetry in Differential Micro Accelerometers

Directory of Open Access Journals (Sweden)

Xiaoping He

2012-05-01

Full Text Available Gap asymmetry in differential capacitors is the primary source of the zero bias output of force-balanced micro accelerometers. It is also used to evaluate the applicability of differential structures in MEMS manufacturing. Therefore, determining the asymmetry level has considerable significance for the design of MEMS devices. This paper proposes an experimental-theoretical method for predicting gap asymmetry in differential sensing capacitors of micro accelerometers. The method involves three processes: first, bi-directional measurement, which can sharply reduce the influence of the feedback circuit on bias output, is proposed. Experiments are then carried out on a centrifuge to obtain the input and output data of an accelerometer. Second, the analytical input-output relationship of the accelerometer with gap asymmetry and circuit error is theoretically derived. Finally, the prediction methodology combines the measurement results and analytical derivation to identify the asymmetric error of 30 accelerometers fabricated by DRIE. Results indicate that the level of asymmetry induced by fabrication uncertainty is about ±5 × 10⁻², and that the absolute error is about ±0.2 µm under a 4 µm gap.

Frontal Brain Asymmetry and Willingness to Pay.

Science.gov (United States)

Ramsøy, Thomas Z; Skov, Martin; Christensen, Maiken K; Stahlhut, Carsten

2018-01-01

Consumers frequently make decisions about how much they are willing to pay (WTP) for specific products and services, but little is known about the neural mechanisms underlying such calculations. In this study, we were interested in testing whether specific brain activation-the asymmetry in engagement of the prefrontal cortex-would be related to consumer choice. Subjects saw products and subsequently decided how much they were willing to pay for each product, while undergoing neuroimaging using electroencephalography. Our results demonstrate that prefrontal asymmetry in the gamma frequency band, and a trend in the beta frequency band that was recorded during product viewing was significantly related to subsequent WTP responses. Frontal asymmetry in the alpha band was not related to WTP decisions. Besides suggesting separate neuropsychological mechanisms of consumer choice, we find that one specific measure-the prefrontal gamma asymmetry-was most strongly related to WTP responses, and was most coupled to the actual decision phase. These findings are discussed in light of the psychology of WTP calculations, and in relation to the recent emergence of consumer neuroscience and neuromarketing.

Hemispheric and facial asymmetry: faces of academe.

Science.gov (United States)

Smith, W M

1998-11-01

Facial asymmetry (facedness) of selected academic faculty members was studied in relation to brain asymmetry and cognitive specialization. Comparisons of facedness were made among humanities faculty (H), faculty members of mathematics and physics (M-P), psychologists (P), and a group of randomly selected individuals (R). Facedness was defined in terms of the relative sizes (in square centimeters) of the two hemifaces. It was predicted that the four groups would show differences in facedness, namely, H, right face bias; M-P, left face bias; P, no bias; and R, no bias. The predictions were confirmed, and the results interpreted in terms of known differences in hemispheric specialization of cognitive functions as they relate to the dominant cognitive activity of each of the different groups. In view of the contralateral control of the two hemifaces (below the eyes) by the two hemispheres of the brain, the two sides of the face undergo differential muscular development, thus creating facial asymmetry. Other factors, such as gender, also may affect facial asymmetry. Suggestions for further research on facedness are discussed.

Regional cerebral blood flow after long-term exposure to carbon disulfide

International Nuclear Information System (INIS)

Aaserud, O.; Russell, D.; Nyberg-Hansen, R.; Joergensen, E.B.; Gjerstad, L.; Rootwelt, K.; Nakstad, P.; Hommeren, O.J.; Tvedt, B.

1992-01-01

Sixteen former rayon viscose workers were investigated four years after the exposure to carbon disulfide was discontinued. Median age was 58 years (range 43-65 years), median exposure time was 17 years (range 10-35 years). Encephalopathy was diagnosed in altogether 14 workers. To further explore pathophysiological mechanisms, cerebrovascular investigations were employed. Doppler ultrasound examination of the precerebral vessels in 15 workers showed a slight stenosis of the left internal carotid artery in one. Regional cerebral blood flow investigation (rCBF) with single photon emission computerized tomography (SPECT) with Xenon-133 gas was performed in 14. There was no significant difference from a control group. Regional side-to-side asymmetries beyond reference limits were demonstrated in eight workers. The abnormalities were modest, but may indicate a tendency toward focal blood flow disturbances in workers with long-term exposure to carbon disulfide. (au)

Regional cerebral blood flow in childhood autism: a SPET study with SPM evaluation.

Science.gov (United States)

Burroni, Luca; Orsi, Alessandra; Monti, Lucia; Hayek, Youssef; Rocchi, Raffaele; Vattimo, Angelo G

2008-02-01

To establish a link between rCBF assessed with Tc-ECD SPET and the clinical manifestation of the disease. We performed the study on 11 patients (five girls and six boys; mean age 11.2 years) displaying autistic behaviour and we compared their data with that of an age-matched reference group of eight normal children. A quantitative analysis of rCBF was performed calculating a perfusion index (PI) and an asymmetry index (AI) in each lobe. Images were analysed with statistical parametric mapping software, following the spatial normalization of SPET images for a standard brain. A statistically significant (P=0.003) global reduction of CBF was found in the group of autistic children (PI=1.07+/-0.07) when compared with the reference group (PI=1.25+/-0.12). Moreover, a significant difference was also observed for the right-to-left asymmetry of hemispheric perfusion between the control group and autistic patients (P=0.0085) with a right prevalence greater in autistic (2.90+/-1.68) with respect to normal children (1.12+/-0.49). Our data show a significant decrease of global cerebral perfusion in autistic children in comparison with their normal counterparts and the existence of left-hemispheric dysfunction, especially in the temporo-parietal areas devoted to language and the comprehension of music and sounds. We suggest that these abnormal areas are related to the cognitive impairment observed in autistic children, such as language deficits, impairment of cognitive development and object representation, and abnormal perception and responses to sensory stimuli. Tc-ECD SPET seems to be sensitive in revealing brain blood flow alterations and left-to-right asymmetries, when neuroradiological patterns are normal.

STUDY OF FACIAL ASYMMETRY IN PATIENTS WITH DENTOMAXILLARY ANOMALIES

Directory of Open Access Journals (Sweden)

Daniela Anistoroaei

2011-09-01

Full Text Available The study aimed at establishing the prevalence index of facial asymmetry by extraoral clinical examination of orthodontic patients. The group of study included 384 subjects, selected from the patients who required a specialized orthodontic treatment. Facial asymmetry was evaluated by the parallelism of the horizontal planes and deviation of the menton and nasal pyramid. The age, sex and ecological environment from which one came, the type of dentition and of dento-maxillary anomaly were registered for each patient in part. In the experimental group, facial asymmetry was present in 4.7% of patients, menton deviation in 5.7%, and nasal pyramid deviation - in 3.4%. Significant associations were established between facial asymmetry and the type of dento-maxillary anomaly, classes of age and type of dentition. The results obtained indicate that the prevalence of facial asymmetries in orthodontic patients is especially important for the clinician, as the deviations should be established prior to the initiation of any orthodontic – possibly surgical - treatment.

Asymmetries in heavy meson production from light quark fragmentation

International Nuclear Information System (INIS)

Dias de Deus, J.; Duraes, F.

2000-01-01

We discuss the possibility of the asymmetry in D - /D + production from π - beams, being a direct consequence of the properties of the light quark fragmentation function into heavy mesons. The main features of the asymmetry, as a function of x F , are easily described. An integrated sum rule for the D - , D + multiplicity difference is presented. Predictions for the asymmetry in B meson production are given. (orig.)

Relaxation along a fictitious field (RAFF and Z-spectroscopy using alternating-phase irradiation (ZAPI in permanent focal cerebral ischemia in rat.

Directory of Open Access Journals (Sweden)

Kimmo T Jokivarsi

Full Text Available Cerebral ischemia alters the molecular dynamics and content of water in brain tissue, which is reflected in NMR relaxation, diffusion and magnetization transfer (MT parameters. In this study, the behavior of two new MRI contrasts, Relaxation Along a Fictitious Field (RAFF and Z-spectroscopy using Alternating-Phase Irradiation (ZAPI, were quantified together with conventional relaxation parameters (T1, T2 and T1ρ and MT ratios in acute cerebral ischemia in rat. The right middle cerebral artery was permanently occluded and quantitative MRI data was acquired sequentially for the above parameters for up to 6 hours. The following conclusions were drawn: 1 Time-dependent changes in RAFF and T1ρ relaxation are not coupled to those in MT. 2 RAFF relaxation evolves more like transverse, rather than longitudinal relaxation. 3 MT measured with ZAPI is less sensitive to ischemia than conventional MT. 4 ZAPI data suggest alterations in the T2 distribution of macromolecules in acute cerebral ischemia. It was shown that both RAFF and ZAPI provide complementary MRI information from acute ischemic brain tissue. The presented multiparametric MRI data may aid in the assessment of brain tissue status early in ischemic stroke.

Quantitative MRI shows cerebral microstructural damage in hemolytic-uremic syndrome patients with severe neurological symptoms but no changes in conventional MRI

Energy Technology Data Exchange (ETDEWEB)

Weissenborn, Karin; Worthmann, Hans; Heeren, Meike [Hannover Medical School, Clinic for Neurology, Hannover (Germany); Bueltmann, Eva; Donnerstag, Frank; Giesemann, Anja M.; Goetz, Friedrich; Lanfermann, Heinrich; Ding, Xiao-Qi [Hannover Medical School, Institute of Diagnostic and Interventional Neuroradiology, Hannover (Germany); Kielstein, Jan; Schwarz, Anke [Hannover Medical School, Clinic for Nephrology and Hypertension, Hannover (Germany)

2013-07-15

Severe neurological symptoms in Shiga toxin-producing Escherichia coli infection associated hemolytic-uremic syndrome (STEC-HUS) are often accompanied by none or only mild alterations of cerebral magnetic resonance imaging (MRI). This study aims to analyze if quantitative MRI is able to reveal cerebral pathological alterations invisible for conventional MRI. In nine patients with STEC-HUS associated severe neurological symptoms but inconspicuous cerebral MRI findings maps of the parameters T2 relaxation time, relative proton density (PD), apparent diffusion coefficient (ADC), and fractional anisotropy (FA) were generated. Quantitative values of these parameters were measured at the basal ganglia, thalamus, and white matter of the frontal and parietal lobe and compared to those of nine age- and sex-matched controls. Significant T2 prolongation (p < 0.01) was found in the basal ganglia of all patients compared to controls. PD and ADC were not significantly altered. A significant reduction of FA in patients was seen at caput nuclei caudati (p < 0.01). Prolonged T2 relaxation time indicates cerebral microstructural damages in these patients despite their inconspicuous MRI findings. T2 relaxometry could be used as a complementary tool for the assessment of metabolic-toxic brain syndromes. (orig.)

Hand preference and magnetic resonance imaging asymmetries of the central sulcus.

Science.gov (United States)

Foundas, A L; Hong, K; Leonard, C M; Heilman, K M

1998-04-01

Hand preference is perhaps the most evident behavioral asymmetry observed in humans. Anatomic brain asymmetries that may be associated with hand preference have not been extensively studied, and no clear relationship between asymmetries of the motor system and hand preference have been established. Therefore, using volumetric magnetic resonance imaging methodologies, the surface area of the hand representation was measured along the length of the central sulcus in 15 consistent right- and 15 left-handers matched for age and gender. There was a significant leftward asymmetry of the motor hand area of the precentral gyrus in the right-handers, but no directional asymmetry was found in the left-handers. When asymmetry quotients were computed to determine the distribution of interhemispheric asymmetries, the left motor bank was greater than the right motor bank in 9 of 15 right-handers, the right motor bank was greater than the left motor bank in 3 of 15 right-handers, and the motor banks were equal in 3 of 15 right-handers. In contrast, among left-handers, the left motor bank was greater than the right motor bank in 5 of 15, the right motor bank was greater than the left motor bank in 5 of 15, and the motor banks were equal in 5 of 15. Although no direct measure of motor dexterity and skill was performed, these data suggest that anatomic asymmetries of the motor hand area may be related to hand preference because of the differences in right-handers and left-handers. Furthermore, the predominant leftward asymmetry in right-handers and the random distribution of asymmetries in the left-handers support Annett's right-shift theory. It is unclear, however, whether these asymmetries are the result of preferential hand use or are a reflection of a biologic preference to use one limb over the other.

New tuning method of the low-mode asymmetry for ignition capsule implosions

International Nuclear Information System (INIS)

Gu, Jianfa; Dai, Zhensheng; Zou, Shiyang; Song, Peng; Ye, Wenhua; Zheng, Wudi; Gu, Peijun

2015-01-01

In the deuterium-tritium inertial confinement fusion implosion experiments on the National Ignition Facility, the hot spot and the surrounding main fuel layer show obvious P2 asymmetries. This may be caused by the large positive P2 radiation flux asymmetry during the peak pulse resulting form the poor propagation of the inner laser beam in the gas-filled hohlraum. The symmetry evolution of ignition capsule implosions is investigated by applying P2 radiation flux asymmetries during different time intervals. A series of two-dimensional simulation results show that a positive P2 flux asymmetry during the peak pulse results in a positive P2 shell ρR asymmetry; while an early time positive P2 flux asymmetry causes a negative P2 in the fuel ρR shape. The opposite evolution behavior of shell ρR asymmetry is used to develop a new tuning method to correct the radiation flux asymmetry during the peak pulse by adding a compensating same-phased P2 drive asymmetry during the early time. The significant improvements of the shell ρR symmetry, hot spot shape, hot spot internal energy, and neutron yield indicate that the tuning method is quite effective. The similar tuning method can also be used to control the early time drive asymmetries

Baryon asymmetry, inflation and squeezed states

International Nuclear Information System (INIS)

Bambah, Bindu A.; Chaitanya, K.V.S. Shiv; Mukku, C.

2007-01-01

We use the general formalism of squeezed rotated states to calculate baryon asymmetry in the wake of inflation through parametric amplification. We base our analysis on a B and CP violating Lagrangian in an isotropically expanding universe. The B and CP violating terms originate from the coupling of complex fields with non-zero baryon number to a complex background inflaton field. We show that a differential amplification of particle and antiparticle modes gives rise to baryon asymmetry

Test of inscribed description in the Alzheimer's disease: correlation of neuro-psychology and of cerebral sanguinary rates

International Nuclear Information System (INIS)

Houzard, C.; Croisile, B.; Philippon, B.; Hibert, O.; Gogoleva, S.M.; Itti, R.; Cinotti, L.; Wertheimer, H.P.

1997-01-01

The alteration of the written description of an image scene constitutes an early and sensible indicator in diagnosing the Alzheimer's disease (AD). Measurements of cerebral blood rates (CBR) by SPECT show characteristic regional anomalies. We have studied correlations between the neuro-psychological tests (NT), parameters of description (description of the image of a thief of crackers) and CBR in patients afflicted by AD. Ten patients afflicted by AD of slow onset (MMSE 20.2± 5.1) were subject to the following NTs: MMSE, Wounded A, Battery of Aphasia, BNT, verbal fluence, gesticulative practice, direct and inversion span, copy of a figure, immediate recall of a figure, immediate recall of a story. The description variables were the length of texts (words, phrases), the items of information, the grammatical, semantic and orthographic errors. The relative variations of CBR were obtained after injection by HMPAO - 99m Tc. The indices of asymmetry were calculated by the method of the regions of interest and the correlations were calculated between the NTs, description variables and L/R asymmetry by SPECT. For the temporal lobes the correlations are significant with: Battery of Aphasia and BNT (p < 0.01), and recall of a story (p < 0.05); in the anterior frontal lobes with: MMSE and direct span (p < 0.05); in the posterior frontal lobes with: Battery of Aphasia (p < 0.05), BNT and recall of a story (p < 0.01). For writing, the grammatical errors are correlated with the anterior frontal asymmetries (p < 0.03); the semantic errors with the anterior and posterior frontal lobes (p < 0.02) and with the temporal lobes (p < 0.05). Our results show a correlations of the frontal and temporal asymmetries with the early degradation of the scores of written semantic errors and the oral tests of language. The grammatical errors appearing later and in severe forms of AD as the attention abilities are connected only to anterior frontal asymmetries. Different functional networks could

Measurement of cerebral blood flow with /sup 133/Xe inhalation and dynamic single photon emission computer tomography. Normal values

Energy Technology Data Exchange (ETDEWEB)

Rootwelt, K; Dybevold, S; Nyberg-Hansen, R; Russell, D

1986-01-01

Cerebral blood flow was studied by /sup 133/Xe inhalation tomography in 25 healthy subjects. Mean age was 41 years and range 23-66 years. Mean hemispheric CBF at rest was 59.8 ml/100 g/min, and cerebellar flow 60.8 ml/100 g/min. The distribution of CBF values was skewed and approximated a log normal distribution. Estimated lower and upper normal reference range limits calculated as mean (log) = - 2 S.D. (log) were 47-74 ml/100 g/min. Women had approximately 5 ml/100 g/min higher CBF values than men, corresponding to the difference in hematocrit. Neither in men or women was there any tendency to age dependent reduction or increase in flow. In both sexes hemispheric regional CBF (rCBF) was asymmetric with higher flow values in the right cerebral hemisphere; particularly in the anterior distribution territory of the middle cerebral artery. Emotional activation as a consequence of the study conditions is assumed to be the cause of this observed asymmetry. Cerebellar flow was not assymetric. No significant difference in cerebellar or hemispheric CBF was found when a second study followed the first by 3-15 months, PCO/sub 2/ correction of flow improved reproducibility. Acetazolamide responses are reported.

Amplitude and polarization asymmetries in a ring laser

Science.gov (United States)

Campbell, L. L.; Buholz, N. E.

1971-01-01

Asymmetric amplitude effects between the oppositely directed traveling waves in a He-Ne ring laser are analyzed both theoretically and experimentally. These effects make it possible to detect angular orientations of an inner-cavity bar with respect to the plane of the ring cavity. The amplitude asymmetries occur when a birefringent bar is placed in the three-mirror ring cavity, and an axial magnetic field is applied to the active medium. A simplified theoretical analysis is performed by using a first order perturbation theory to derive an expression for the polarization of the active medium, and a set of self-consistent equations are derived to predict threshold conditions. Polarization asymmetries between the oppositely directed waves are also predicted. Amplitude asymmetries similar in nature to those predicted at threshold occur when the laser is operating in 12-15 free-running modes, and polarization asymmetry occurs simultaneously.

Rare decays and CP asymmetries in charged B decays

International Nuclear Information System (INIS)

Deshpande, N.G.

1991-01-01

The theory of loop induced rare decays and the rate asymmetry due to CP violation in charged B Decays in reviewed. After considering b → sγ and b → se + e - decays, the asymmetries for pure penguin process are estimated first. A larger asymmetry can result in those modes where a tree diagram and a penguin diagram interfere, however these estimates are necessarily model dependent. Estimates of Cabbibo suppressed penguins are also considered

Unilateral cerebral polymicrogyria with ipsilateral cerebral hemiatrophy

Energy Technology Data Exchange (ETDEWEB)

Hayakawa, Katsumi [Department of Radiology, Kyoto City Hospital, 1-2 Higashi-Takada-cho, Mibu, Nakagyo-ku, 604-8845 Kyoto (Japan); Kanda, Toyoko; Yamori, Yuriko [Department of Pediatric Neurology, St. Joseph Hospital for Handicapped Children, 603-8323 Kyoto (Japan)

2002-10-01

We evaluated six children in whom MR imaging showed unilateral cerebral polymicrogyria associated with ipsilateral cerebral atrophy and ipsilateral brain stem atrophy. The aim of this study was to clarify whether this disorder based on neuroimaging constitutes a new homogeneous clinical entity. The subjects were six children whose ages at the time of MR imaging ranged from 8 months to 11 years. Their clinical and MR features were analyzed. All of the children were born between 38 and 42 weeks gestation, without any significant perinatal events. Spastic hemiplegia and epilepsy were observed in all of the patients, and mental retardation was observed in four. The MR findings included unilateral cerebral polymicrogyria associated with ipsilateral cerebral hemiatrophy and ipsilateral brain stem atrophy in all patients. The ipsilateral sylvian fissure was hypoplastic in four patients. These patients showed relatively homogeneous clinical and neuroimaging features. Although the additional clinical features varied according to the site and the extent affected by the polymicrogyria, this disorder could constitute a new relatively homogeneous clinical entity. (orig.)

Unilateral cerebral polymicrogyria with ipsilateral cerebral hemiatrophy

International Nuclear Information System (INIS)

Hayakawa, Katsumi; Kanda, Toyoko; Yamori, Yuriko

2002-01-01

We evaluated six children in whom MR imaging showed unilateral cerebral polymicrogyria associated with ipsilateral cerebral atrophy and ipsilateral brain stem atrophy. The aim of this study was to clarify whether this disorder based on neuroimaging constitutes a new homogeneous clinical entity. The subjects were six children whose ages at the time of MR imaging ranged from 8 months to 11 years. Their clinical and MR features were analyzed. All of the children were born between 38 and 42 weeks gestation, without any significant perinatal events. Spastic hemiplegia and epilepsy were observed in all of the patients, and mental retardation was observed in four. The MR findings included unilateral cerebral polymicrogyria associated with ipsilateral cerebral hemiatrophy and ipsilateral brain stem atrophy in all patients. The ipsilateral sylvian fissure was hypoplastic in four patients. These patients showed relatively homogeneous clinical and neuroimaging features. Although the additional clinical features varied according to the site and the extent affected by the polymicrogyria, this disorder could constitute a new relatively homogeneous clinical entity. (orig.)

Asymmetry dependence of the nuclear caloric curve

International Nuclear Information System (INIS)

McIntosh, A.B.; Bonasera, A.; Cammarata, P.; Hagel, K.; Heilborn, L.; Kohley, Z.; Mabiala, J.; May, L.W.; Marini, P.; Raphelt, A.; Souliotis, G.A.; Wuenschel, S.; Zarrella, A.; Yennello, S.J.

2013-01-01

A basic feature of the nuclear equation of state is not yet understood: the dependence of the nuclear caloric curve on the neutron–proton asymmetry. Predictions of theoretical models differ on the magnitude and even the sign of this dependence. In this work, the nuclear caloric curve is examined for fully reconstructed quasi-projectiles around mass A=50. The caloric curve extracted with the momentum quadrupole fluctuation thermometer shows that the temperature varies linearly with quasi-projectile asymmetry (N−Z)/A . An increase in asymmetry of 0.15 units corresponds to a decrease in temperature on the order of 1 MeV. These results also highlight the importance of a full quasi-projectile reconstruction in the study of thermodynamic properties of hot nuclei

CP asymmetries in semiinclusive B0 decays

Energy Technology Data Exchange (ETDEWEB)

Dunietz, Isard

1999-02-01

It was recently pointed out that inclusive B^0(t) decays could show CP violation. The totally inclusive asymmetry is expected to be tiny [O(10^{-3})] because of large cancellations among the asymmetries in the charmless, single charm and double charm final states. Enriching particular final state configurations could significantly increase the CP-asymmetry and observability. Such studies can extract fundamental CKM (Cabibbo-Kobayashi-Maskawa) parameters, and (perhaps) even Delta m(B_s). A superb vertex detector could see CP violation with 10^5 (10^6) flavor-tagged B_s (B_d) mesons within the CKM model. Because the effects could be significantly larger due to new physics, they should be searched for in existing or soon available data samples.

Frontal EEG asymmetry in borderline personality disorder is associated with alexithymia.

Science.gov (United States)

Flasbeck, Vera; Popkirov, Stoyan; Brüne, Martin

2017-01-01

Frontal EEG asymmetry is a widely studied correlate of emotion processing and psychopathology. Recent research suggests that frontal EEG asymmetry during resting state is related to approach/withdrawal motivation and is also found in affective disorders such as major depressive disorder. Patients with borderline personality disorder (BPD) show aberrant behavior in relation to both approach and withdrawal motivation, which may arguably be associated with their difficulties in emotion processing. The occurrence and significance of frontal EEG asymmetry in BPD, however, has received little attention. Thirty-seven BPD patients and 39 controls underwent resting EEG and completed several psychometric questionnaires. While there were no between-group differences in frontal EEG asymmetry, in BPD frontal EEG asymmetry scores correlated significantly with alexithymia. That is, higher alexithymia scores were associated with relatively lower right-frontal activity. A subsequent analysis corroborated the significant interaction between frontal EEG asymmetry and alexithymia, which was moderated by group. Our findings reveal that lower right frontal EEG asymmetry is associated with alexithymia in patients with BPD. This finding is in accordance with neurophysiological models of alexithymia that implicate a right hemisphere impairment in emotion processing, and could suggest frontal EEG asymmetry as a potential biomarker of relevant psychopathology in these patients.

Baryogenesis and Dark Matter through a Higgs Asymmetry

CERN Document Server

Servant, Geraldine

2013-01-01

In addition to explaining the masses of elementary particles, the Higgs boson may have far-reaching implications for the generation of the matter content in the Universe. For instance, the Higgs plays a key role in two main theories of baryogenesis, namely electroweak baryogenesis and leptogenesis. In this letter, we propose a new cosmological scenario where the Higgs chemical potential mediates asymmetries between visible and dark matter sectors, either generating a baryon asymmetry from a dark matter asymmetry or vice-versa. We illustrate this mechanism with a simple model with two new fermions coupled to the Higgs and discuss associated signatures.

Bottom production asymmetries at the LHC

Energy Technology Data Exchange (ETDEWEB)

Norrbin, E.; Vogt, R.

1999-01-01

We present results on bottom hadron production asymmetries at the LHC within both the Lund string fragmentation model and the intrinsic bottom model. The main aspects of the models are summarized and specific predictions for pp collisions at 14 TeV are given. Asymmetries are found to be very small at central rapidities increasing to a few percent at forward rapidities. At very large rapidities intrinsic production could dominate but this region is probably out of reach of any experiment.

Bottom production asymmetries at the LHC

International Nuclear Information System (INIS)

Norrbin, E.; Vogt, R.

1999-01-01

We present results on bottom hadron production asymmetries at the LHC within both the Lund string fragmentation model and the intrinsic bottom model. The main aspects of the models are summarized and specific predictions for pp collisions at 14 TeV are given. Asymmetries are found to be very small at central rapidities increasing to a few percent at forward rapidities. At very large rapidities intrinsic production could dominate but this region is probably out of reach of any experiment

Left-right asymmetry in neutrino-produced hadron jets

International Nuclear Information System (INIS)

Ballagh, H.C.; Bingham, H.H.; Lawry, T.J.; Lys, J.; Lynch, G.R.; Sokoloff, M.D.; Stevenson, M.L.; Huson, F.R.; Schmidt, E.; Smart, W.; Treadwell, E.; Cence, R.J.; Harris, F.A.; Jones, M.D.; Koide, A.; Peters, M.W.; Peterson, V.Z.; Lubatti, H.J.; Moriyasu, K.; Wolin, E.

1989-01-01

In an experiment (E546) to study interactions of left-angle E right-angle=100 GeV and left-angle Q 2 right-angle=17 GeV 2 neutrinos in the Fermilab 15-foot bubble chamber, we have looked for a left-right asymmetry in the azimuthal angle φ of individual hadrons about the direction of the lepton momentum transfer (q vector). Significant asymmetry is found for forward positive hadrons; for x F >0.10, we find left-angle cosφ right-angle=-0.029±0.008, where x F is the Feynman x variable. Negative hadrons with x F >0.10 show no asymmetry, left-angle cosφ right-angle=0.004±0.011. A model which includes parton intrinsic transverse momentum k t reproduces the asymmetry of combined positive and negative hadrons with x F >0.10, left-angle cosφ right-angle=-0.018±0.0065, if left-angle k t 2 right-angle=0.065±0.024 GeV 2 /c 2 . But the model predicts almost equal asymmetries for positive and negative hadrons. The model also agrees poorly with the observed dependence on the kinematic variables x and Q 2 if the k t distribution is assumed to be independent of kinematic variables

Asymmetry of the structural brain connectome in healthy older adults.

Directory of Open Access Journals (Sweden)

Leonardo eBonilha

2014-01-01

Full Text Available Background: It is now possible to map neural connections in vivo across the whole brain (i.e., the brain connectome. This is a promising development in neuroscience since many health and disease processes are believed to arise from the architecture of neural networks.Objective: To describe the normal range of hemispheric asymmetry in structural connectivity in healthy older adults.Methods: We obtained high-resolution structural magnetic resonance images (MRI from 17 healthy older adults. For each subject, the brain connectome was reconstructed by parcelating the probabilistic map of gray matter into anatomically defined regions of interested (ROIs. White matter fiber tractography was reconstructed from diffusion tensor imaging and streamlines connecting gray matter ROIs were computed. Asymmetry indices were calculated regarding ROI connectivity (representing the sum of connectivity weight of each cortical ROI and for regional white matter links. All asymmetry measures were compared to a normal distribution with mean=0 through one sample t-tests.Results: Leftward cortical ROI asymmetry was observed in medial temporal, dorsolateral frontal and occipital regions. Rightward cortical ROI asymmetry was observed in middle temporal and orbito-frontal regions. Link-wise asymmetry revealed stronger connections in the left hemisphere between the medial temporal, anterior and posterior peri-Sylvian and occipito-temporal regions. Rightward link asymmetry was observed in lateral temporal, parietal and dorsolateral frontal connections.Conclusions: We postulate that asymmetry of specific connections may be related to functional hemispheric organization. This study may provide reference for future studies evaluating the architecture of the connectome in health and disease processes in senior individuals.

Cerebral palsy and congenital malformations

DEFF Research Database (Denmark)

Garne, Ester; Dolk, Helen; Krägeloh-Mann, Inge

2007-01-01

AIM: To determine the proportion of children with cerebral palsy (CP) who have cerebral and non-cerebral congenital malformations. METHODS: Data from 11 CP registries contributing to the European Cerebral Palsy Database (SCPE), for children born in the period 1976-1996. The malformations were...... classified as recognized syndromes, chromosomal anomalies, cerebral malformations or non-cerebral malformations. Prevalence of malformations was compared to published data on livebirths from a European database of congenital malformations (EUROCAT). RESULTS: Overall 547 out of 4584 children (11.9%) with CP...... were reported to have a congenital malformation. The majority (8.6% of all children) were diagnosed with a cerebral malformation. The most frequent types of cerebral malformations were microcephaly and hydrocephaly. Non-cerebral malformations were present in 97 CP children and in further 14 CP children...

Cerebral metabolism, anatomy, and cognition in monozygotic twins discordant for dementia of the Alzheimer type.

Science.gov (United States)

Luxenberg, J S; May, C; Haxby, J V; Grady, C; Moore, A; Berg, G; White, B J; Robinette, D; Rapoport, S I

1987-03-01

One pair of monozygotic twins discordant for dementia of the Alzheimer type (DAT) was studied using neuropsychological testing, quantitative x-ray computed tomography (QCT) and magnetic resonance imaging (MRI) of the brain. Cerebral glucose metabolism was measured using positron emission tomography (PET) and 2-[18-F]fluoro-2-deoxy-D-glucose (FDG). The affected twin had a seven year history of progressive cognitive impairment and was severely demented. Neuropsychological testing of the affected twin demonstrated marked deficits in all areas of cognitive function. The asymptomatic twin showed some impairment on tests of perceptual organisation and delayed recall. The affected twin had loss of gray matter and ventricular enlargement on QCT and MRI compared with healthy controls (p less than 0.05). He also had frontal and parietal lobe hypometabolism and increased asymmetry of metabolism on PET compared to both his twin and healthy age-matched controls (p less than 0.05). PET, QCT, and MRI distinguished changes in the twin with DAT compared with his brother and healthy controls. Although the subtle neuropsychological abnormalities of the asymptomatic twin may be signs of early DAT, they were not accompanied by any changes in regional cerebral metabolism or brain structure.

L-R asymmetry in gut's

International Nuclear Information System (INIS)

Karadayi, H.R.

1982-01-01

An idea of L-R asymmetry is proposed for the grand unification schemes. The idea provides an intrinsic mechanism to obtain standard model charges of fermions in the case of more than one weak gauge boson. It is elaborated within a scheme based on the partial symmetry SU(4)sub(C)xSU(2)sub(L)xSU(2)sub(R) where the coupling constants gsub(L) and gsub(R) corresponding to the chiral SU(2) factors are assumed to be different from each other. Then, the embedding of this structure within the simple symmetry SO(10) is shown. In both cases, a consistent description of vector particle masses is given. These two schemes are considered as primary models to realize the L-R asymmetry idea due to the lack of family unification. However, in a subsequent work, we will show that the SO(14) unification of the three families can be obtained within the framework of L-R asymmetry. All formulations are carried out with the aid of a mathematical method that we recently proposed for the Lie algebra representations of classical groups. (author)

Investor relations and information asymmetry

Directory of Open Access Journals (Sweden)

Sandrielem da Silva Rodrigues

2017-03-01

Full Text Available ABSTRACT Companies invest significant volumes of resources in investor relations (IR departments. The professionals working in the IR department are responsible for communication between the company and the market, so that the information generated is widely disseminated and understood by investors. In this context, this research aims to investigate whether there is evidence that the IR activity decreases information asymmetry between the company and the market. Specifically, we evaluate the hypothesis that Brazilian companies with IR websites classified as more informative have a reduced bid-ask spread (proxy for asymmetry. Therefore, this paper classifies the informative content from IR websites of Brazilian companies for the years 2013 and 2014 and relates the outcomes obtained with information asymmetry metrics. Initially, the estimation considers the pooled ordinary least squares (POLS model and, at a second moment, in order to mitigate potential endogeneity problems, the pooled two-stage least squares (2SLS model is used. The results indicate that more informative IR websites are able to decrease the bid-ask spread of Brazilian listed companies. This finding strongly encourages companies to provide information to stakeholders on well-structured IR websites of their own.

INFORMATION ASYMMETRY AND HERDING BEHAVIOR

Directory of Open Access Journals (Sweden)

Puput Tri Komalasari

2016-06-01

Full Text Available Conceptually, the stock market is strong form efficient in the long term. However, in practice, there are various forms of market anomalies that undermine the accuracy of the efficient market hypothesis. One factor suspected as the cause of market inefficiency is herding behavior. Investors herd when they imitate the actions of other investors. This behavior occurs when there is a continuous interaction among rational investors that prevents them from seeking information about market fundamentals. This study provides new insights by including information asymmetry as a moderating variable. This research examines the phenomenon of herding behavior in the Indonesia Stock Exchange as well as examines directly the effect of information asymmetry on herding behavior. The period of study is 2008 using time series of daily stocks data that actively traded in the capital market. Results of this study find that investor tends to follow market consensus when price changes at the low level, but when there is large price swing market participant acts independently from other investors. Interestingly, this study finds that information asymmetry is a necessary condition for the existence of herding behavior.

Cerebral Palsy

Science.gov (United States)

Cerebral palsy is a group of disorders that affect a person's ability to move and to maintain balance ... do not get worse over time. People with cerebral palsy may have difficulty walking. They may also have ...

[Presurgical orthodontics for facial asymmetry].

Science.gov (United States)

Labarrère, H

2003-03-01

As with the treatment of all facial deformities, orthodontic pre-surgical preparation for facial asymmetry should aim at correcting severe occlusal discrepancies not solely on the basis of a narrow occlusal analysis but also in a way that will not disturb the proposed surgical protocol. In addition, facial asymmetries require specific adjustments, difficult to derive and to apply because of their inherent atypical morphological orientation of both alveolar and basal bony support. Three treated cases illustrate different solutions to problems posed by pathological torque: this torque must be considered with respect to proposed surgical changes, within the framework of their limitations and their possible contra-indications.

Axial asymmetry, finite particle number and the IBA

International Nuclear Information System (INIS)

Casten, R.F.

1984-01-01

Although the IBA-1 contains no solutions corresponding to a rigid triaxial shape, it does contain an effective asymmetry. This arises from zero point motion in a γ-soft potential leading to a non-zero mean or rms γ. Three aspects of this feature will be discussed: (1) The relation between IBA-1 calculations and the corresponding γ. This point is developed in the context of the Consistent Q Formalism (CQF) of the IBA. (2) The dependence of this asymmetry on boson number, N, and the exploitation of this dependence to set limits on both the relative and absolute values of N for deformed nuclei. (3) The relation between this asymmetry and the triaxiality arising from the introduction of cubic terms into the IBA Hamiltonian. Various observables will be inspected in order both to determine their sensitivity to these two structural features and to explore empirical ways of distinguishing which origin of asymmetry applies in any given nucleus. 16 references

microRNA function in left-right neuronal asymmetry: perspectives from C. elegans.

Science.gov (United States)

Alqadah, Amel; Hsieh, Yi-Wen; Chuang, Chiou-Fen

2013-09-23

Left-right asymmetry in anatomical structures and functions of the nervous system is present throughout the animal kingdom. For example, language centers are localized in the left side of the human brain, while spatial recognition functions are found in the right hemisphere in the majority of the population. Disruption of asymmetry in the nervous system is correlated with neurological disorders. Although anatomical and functional asymmetries are observed in mammalian nervous systems, it has been a challenge to identify the molecular basis of these asymmetries. C. elegans has emerged as a prime model organism to investigate molecular asymmetries in the nervous system, as it has been shown to display functional asymmetries clearly correlated to asymmetric distribution and regulation of biologically relevant molecules. Small non-coding RNAs have been recently implicated in various aspects of neural development. Here, we review cases in which microRNAs are crucial for establishing left-right asymmetries in the C. elegans nervous system. These studies may provide insight into how molecular and functional asymmetries are established in the human brain.

microRNA function in left-right neuronal asymmetry: perspectives from C. elegans

Directory of Open Access Journals (Sweden)

Amel eAlqadah

2013-09-01

Full Text Available Left-right asymmetry in anatomical structures and functions of the nervous system is present throughout the animal kingdom. For example, language centers are localized in the left side of the human brain, while spatial recognition functions are found in the right hemisphere in the majority of the population. Disruption of asymmetry in the nervous system is correlated with neurological disorders. Although anatomical and functional asymmetries are observed in mammalian nervous systems, it has been a challenge to identify the molecular basis of these asymmetries. C. elegans has emerged as a prime model organism to investigate molecular asymmetries in the nervous system, as it has been shown to display functional asymmetries clearly correlated to asymmetric distribution and regulation of biologically relevant molecules. Small non-coding RNAs have been recently implicated in various aspects of neural development. Here, we review cases in which microRNAs are crucial for establishing left-right asymmetries in the C. elegans nervous system. These studies may provide insight into how molecular and functional asymmetries are established in the human brain.

Left-right asymmetries of behaviour and nervous system in invertebrates.

Science.gov (United States)

Frasnelli, Elisa; Vallortigara, Giorgio; Rogers, Lesley J

2012-04-01

Evidence of left-right asymmetries in invertebrates has begun to emerge, suggesting that lateralization of the nervous system may be a feature of simpler brains as well as more complex ones. A variety of studies have revealed sensory and motor asymmetries in behaviour, as well as asymmetries in the nervous system, in invertebrates. Asymmetries in behaviour are apparent in olfaction (antennal asymmetries) and in vision (preferential use of the left or right visual hemifield during activities such as foraging or escape from predators) in animals as different as bees, fruitflies, cockroaches, octopuses, locusts, ants, spiders, crabs, snails, water bugs and cuttlefish. Asymmetries of the nervous system include lateralized position of specific brain structures (e.g., in fruitflies and snails) and of specific neurons (e.g., in nematodes). As in vertebrates, lateralization can occur both at the individual and at the population-level in invertebrates. Theoretical models have been developed supporting the hypothesis that the alignment of the direction of behavioural and brain asymmetries at the population-level could have arisen as a result of social selective pressures, when individually asymmetrical organisms had to coordinate with each other. The evidence reviewed suggests that lateralization at the population-level may be more likely to occur in social species among invertebrates, as well as vertebrates. Copyright © 2012 Elsevier Ltd. All rights reserved.

Shifting brain asymmetry: the link between meditation and structural lateralization.

Science.gov (United States)

Kurth, Florian; MacKenzie-Graham, Allan; Toga, Arthur W; Luders, Eileen

2015-01-01

Previous studies have revealed an increased fractional anisotropy and greater thickness in the anterior parts of the corpus callosum in meditation practitioners compared with control subjects. Altered callosal features may be associated with an altered inter-hemispheric integration and the degree of brain asymmetry may also be shifted in meditation practitioners. Therefore, we investigated differences in gray matter asymmetry as well as correlations between gray matter asymmetry and years of meditation practice in 50 long-term meditators and 50 controls. We detected a decreased rightward asymmetry in the precuneus in meditators compared with controls. In addition, we observed that a stronger leftward asymmetry near the posterior intraparietal sulcus was positively associated with the number of meditation practice years. In a further exploratory analysis, we observed that a stronger rightward asymmetry in the pregenual cingulate cortex was negatively associated with the number of practice years. The group difference within the precuneus, as well as the positive correlations with meditation years in the pregenual cingulate cortex, suggests an adaptation of the default mode network in meditators. The positive correlation between meditation practice years and asymmetry near the posterior intraparietal sulcus may suggest that meditation is accompanied by changes in attention processing. © The Author (2014). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

Magnetic fields and chiral asymmetry in the early hot universe

Energy Technology Data Exchange (ETDEWEB)

Sydorenko, Maksym; Shtanov, Yuri [Bogolyubov Institute for Theoretical Physics, 03680 Kiev (Ukraine); Tomalak, Oleksandr, E-mail: maxsydorenko@gmail.com, E-mail: tomalak@uni-mainz.de, E-mail: shtanov@bitp.kiev.ua [Institut für Kernphysik, Johannes Gutenberg Universität, 55128 Mainz (Germany)

2016-10-01

In this paper, we study analytically the process of external generation and subsequent free evolution of the lepton chiral asymmetry and helical magnetic fields in the early hot universe. This process is known to be affected by the Abelian anomaly of the electroweak gauge interactions. As a consequence, chiral asymmetry in the fermion distribution generates magnetic fields of non-zero helicity, and vice versa. We take into account the presence of thermal bath, which serves as a seed for the development of instability in magnetic field in the presence of externally generated lepton chiral asymmetry. The developed helical magnetic field and lepton chiral asymmetry support each other, considerably prolonging their mutual existence, in the process of 'inverse cascade' transferring magnetic-field power from small to large spatial scales. For cosmologically interesting initial conditions, the chiral asymmetry and the energy density of helical magnetic field are shown to evolve by scaling laws, effectively depending on a single combined variable. In this case, the late-time asymptotics of the conformal chiral chemical potential reproduces the universal scaling law previously found in the literature for the system under consideration. This regime is terminated at lower temperatures because of scattering of electrons with chirality change, which exponentially washes out chiral asymmetry. We derive an expression for the termination temperature as a function of the chiral asymmetry and energy density of helical magnetic field.

Magnetic fields and chiral asymmetry in the early hot universe

International Nuclear Information System (INIS)

Sydorenko, Maksym; Shtanov, Yuri; Tomalak, Oleksandr

2016-01-01

In this paper, we study analytically the process of external generation and subsequent free evolution of the lepton chiral asymmetry and helical magnetic fields in the early hot universe. This process is known to be affected by the Abelian anomaly of the electroweak gauge interactions. As a consequence, chiral asymmetry in the fermion distribution generates magnetic fields of non-zero helicity, and vice versa. We take into account the presence of thermal bath, which serves as a seed for the development of instability in magnetic field in the presence of externally generated lepton chiral asymmetry. The developed helical magnetic field and lepton chiral asymmetry support each other, considerably prolonging their mutual existence, in the process of 'inverse cascade' transferring magnetic-field power from small to large spatial scales. For cosmologically interesting initial conditions, the chiral asymmetry and the energy density of helical magnetic field are shown to evolve by scaling laws, effectively depending on a single combined variable. In this case, the late-time asymptotics of the conformal chiral chemical potential reproduces the universal scaling law previously found in the literature for the system under consideration. This regime is terminated at lower temperatures because of scattering of electrons with chirality change, which exponentially washes out chiral asymmetry. We derive an expression for the termination temperature as a function of the chiral asymmetry and energy density of helical magnetic field.

Visual search asymmetries within color-coded and intensity-coded displays.

Science.gov (United States)

Yamani, Yusuke; McCarley, Jason S

2010-06-01

Color and intensity coding provide perceptual cues to segregate categories of objects within a visual display, allowing operators to search more efficiently for needed information. Even within a perceptually distinct subset of display elements, however, it may often be useful to prioritize items representing urgent or task-critical information. The design of symbology to produce search asymmetries (Treisman & Souther, 1985) offers a potential technique for doing this, but it is not obvious from existing models of search that an asymmetry observed in the absence of extraneous visual stimuli will persist within a complex color- or intensity-coded display. To address this issue, in the current study we measured the strength of a visual search asymmetry within displays containing color- or intensity-coded extraneous items. The asymmetry persisted strongly in the presence of extraneous items that were drawn in a different color (Experiment 1) or a lower contrast (Experiment 2) than the search-relevant items, with the targets favored by the search asymmetry producing highly efficient search. The asymmetry was attenuated but not eliminated when extraneous items were drawn in a higher contrast than search-relevant items (Experiment 3). Results imply that the coding of symbology to exploit visual search asymmetries can facilitate visual search for high-priority items even within color- or intensity-coded displays. PsycINFO Database Record (c) 2010 APA, all rights reserved.

Short-term tidal asymmetry inversion in a macrotidal estuary (Beira, Mozambique)

Science.gov (United States)

Nzualo, Teodósio N. M.; Gallo, Marcos N.; Vinzon, Susana B.

2018-05-01

The distortion of the tide in estuaries, bays and coastal areas is the result of the generation of overtides due to the non-linear effects associated with friction, advection, and the finite effects of the tidal amplitude in shallow waters. The Beira estuary is classified as macrotidal, with a large ratio of S2/M2. Typical tides ranges from 6 m and 0.8 m, during springs and neaps tides, respectively. As a consequence of this large fortnightly tidal amplitude difference and the estuarine morphology, asymmetry inversions occur. Two types of tidal asymmetries were investigated in this paper, one considering tidal duration asymmetry (time difference between rising and falling tide) and the other, related to tidal velocity asymmetry (unequal magnitudes of flood and ebb peaks currents). In the Beira estuary when we examine the tidal duration asymmetry, flood dominance is observed during spring tide periods (negative time difference between rising and falling tide), while ebb dominance appears during neap tides (positive time difference between rising and falling tide). A 2DH hydrodynamic model was implemented to analyze this asymmetry inversion. The model was calibrated with water-level data measured at the Port of Beira and current data measured along the estuary. The model was run for different scenarios considering tidal constituents at the ocean boundary, river discharge and the morphology of the estuary. River discharge did not show significant effects on the tidal duration asymmetry. Through comparison of the scenarios, it was shown that the incoming ocean tide at the boundary has an ebb-dominant asymmetry, changing to flood-dominant only during spring tides due to the effect of shoaling and friction within the estuary. During neap tides, the propagation occurs mainly in the channels, and ebb dominance remains. The interplay between the estuary morphodynamics was thus identified and the relation between tidal duration asymmetry and tidal velocity asymmetry was

The validity of individual frontal alpha asymmetry EEG neurofeedback.

Science.gov (United States)

Quaedflieg, C W E M; Smulders, F T Y; Meyer, T; Peeters, F; Merckelbach, H; Smeets, T

2016-01-01

Frontal asymmetry in alpha oscillations is assumed to be associated with psychopathology and individual differences in emotional responding. Brain-activity-based feedback is a promising tool for the modulation of cortical activity. Here, we validated a neurofeedback protocol designed to change relative frontal asymmetry based on individual alpha peak frequencies, including real-time average referencing and eye-correction. Participants (N = 60) were randomly assigned to a right, left or placebo neurofeedback group. Results show a difference in trainability between groups, with a linear change in frontal alpha asymmetry over time for the right neurofeedback group during rest. Moreover, the asymmetry changes in the right group were frequency and location specific, even though trainability did not persist at 1 week and 1 month follow-ups. On the behavioral level, subjective stress on the second test day was reduced in the left and placebo neurofeedback groups, but not in the right neurofeedback group. We found individual differences in trainability that were dependent on training group, with participants in the right neurofeedback group being more likely to change their frontal asymmetry in the desired direction. Individual differences in trainability were also reflected in the ability to change frontal asymmetry during the feedback. © The Author (2015). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

Genetic modification of cerebral arterial wall: implications for prevention and treatment of cerebral vasospasm.

Science.gov (United States)

Vijay, Anantha; Santhanam, R; Katusic, Zvonimir S

2006-10-01

Genetic modification of cerebral vessels represents a promising and novel approach for prevention and/or treatment of various cerebral vascular disorders, including cerebral vasospasm. In this review, we focus on the current understanding of the use of gene transfer to the cerebral arteries for prevention and/or treatment of cerebral vasospasm following subarachnoid hemorrhage (SAH). We also discuss the recent developments in vascular therapeutics, involving the autologous use of progenitor cells for repair of damaged vessels, as well as a cell-based gene delivery approach for the prevention and treatment of cerebral vasospasm.

Sagittal otolith morphogenesis asymmetry in marine fishes.

Science.gov (United States)

Mille, T; Mahe, K; Villanueva, M C; De Pontual, H; Ernande, B

2015-09-01

This study investigated and compared asymmetry in sagittal otolith shape and length between left and right inner ears in four roundfish and four flatfish species of commercial interest. For each species, the effects of ontogenetic changes (individual age and total body length), sexual dimorphism (individual sex) and the otolith's location on the right or left side of the head, on the shape and length of paired otoliths (between 143 and 702 pairs according to species) were evaluated. Ontogenetic changes in otolith shape and length were observed for all species. Sexual dimorphism, either in otolith shape and length or in their ontogenetic changes, was detected for half of the species, be they round or flat. Significant directional asymmetry in otolith shape and length was detected in one roundfish species each, but its inconsistency across species and its small average amplitude (6·17% for shape and 1·99% for length) suggested that it has barely any biological relevance. Significant directional asymmetry in otolith shape and length was found for all flatfish species except otolith length for one species. Its average amplitude varied between 2·06 and 17·50% for shape and between 0·00 and 11·83% for length and increased significantly throughout ontogeny for two species, one dextral and one sinistral. The longer (length) and rounder otolith (shape) appeared to be always on the blind side whatever the species. These results suggest differential biomineralization between the blind and ocular inner ears in flatfish species that could result from perturbations of the proximal-distal gradient of otolith precursors in the endolymph and the otolith position relative to the geometry of the saccular epithelium due to body morphology asymmetry and lateralized behaviour. The fact that asymmetry never exceeded 18% even at the individual level suggests an evolutionary canalization of otolith shape symmetry to avoid negative effects on fish hearing and balance. Technically

Cerebral blood flow assessed by brain SPECT with 99mTc-HMPAO utilising the acetazolamide test in systemic lupus erythematosus

International Nuclear Information System (INIS)

Lass, P.; Romanowicz, G.; Koseda-Dragan, M.

1998-01-01

Background: Cerebrovascular diseases are one of the most important complications of systemic lupus erythematosus (SLE). The diagnostic imaging of neuropsychiatric SLE complications presents many problems. This study was undertaken to investigate cerebral blood flow char s and its reactivity to hypercapnia by means of acetazolamide test in SLE patients. Methods: Brain SPECT studies using 99mTc-HMPAO were performed in 50 patients with SLE. Acetazolamide test was performed in 35 patients 3 days after the baseline study by means of repetitive scanning 20 min after i.v. injection of 1.0 g of acetazolamide. Results: Significant interhemispheric hypoperfusion areas were shown in 76.3% of all patients, 83.8% symptomatic and 63.1% asymptomatic. Patients with antiphospholipid syndrome showed multifocal perfusion deficits. The reaction of cerebral perfusion to acetazolamide was heterogenous and showed increase, decrease, no change or mixed reaction of baseline-study-found focal hypoperfusion. Acetazolamide test revealed hypoperfusion in two patients with normal baseline study. MRI scanning revealed cerebral lesions in 41% of patients. Conclusions: CBF asymmetries in symptomatic and asymptomatic patients with SLE are frequent. Regional CBF alterations seem to be different in patients with and without antiphospholipid syndrome. The part of the patients with SLE shows no or paradoxically inversed reaction to acetazolamide. (author)

The electroweak polarization asymmetry: A guided tour

International Nuclear Information System (INIS)

Kennedy, D.C.

1988-10-01

A comprehensive review is provided of the electroweak polarization asymmetry at the Z 0 , a highly accurate measure of the Z 0 coupling to fermions. Its significance as a precision test of the Standard Model is explored in detail. Emphasized are the role of electroweak symmetry-breaking and radiative corrections; the non-decoupling of new physics beyond the Z 0 ; and the testing of extensions of the Standard Model, such as supersymmetry, technicolor, new generations of fermions, grand unification, and new gauge forces. Also discussed are the relationship of the polarization asymmetry to other electroweak observables and its superiority to other Z 0 asymmetries. Experimental issues are briefly presented, stressing the importance of polarization at the SLC and LEP e + e - colliders. 42 refs., 13 figs., 2 tabs

Forward-backward asymmetries in W and Z decays

International Nuclear Information System (INIS)

Rosner, J.L.; Langacker, P.; Robinett, R.W.

1984-01-01

The leptons emitted in decays of W and Z bosons produced in pp or anti pp collisions exhibit characteristic asymmetries with respect to the beam direction, as measured in the W or Z center-of-mass. The asymmetries appear in both pp and anti pp collisions. For anti pp collisions they appear to be approximately constant over the whole y range for values of M/√s greater than or equal to 0.1. For smaller values of M/√s, the asymmetries become more and more washed out in the central region as sea-sea collisions begin to play a larger role in gauge boson formation

Next to leading order semi-inclusive spin asymmetries

International Nuclear Information System (INIS)

Florian, D. de; Epele, L.N.; Fanchiotti, H.; Garcia C, C.A.; Sassot, R.

1996-04-01

We have computed semi-inclusive spin asymmetries for proton and deuteron targets including next to leading order (NLO) QCD corrections and contributions coming from the target fragmentation region. These corrections have been estimated using NLO fragmentation functions, parton distributions and also a model for spin dependent fracture functions which is proposed here. We have found that NLO corrections are small but non-negligible in a scheme where gluons are polarised and that our estimate for target fragmentation effects, which is in agreement with the available semi-inclusive data, does not modify significantly charged asymmetries but is non-negligible for the so called difference asymmetries. (author). 18 refs., 7 figs

Baryogenesis and dark matter through a Higgs asymmetry.

Science.gov (United States)

Servant, Géraldine; Tulin, Sean

2013-10-11

In addition to explaining the masses of elementary particles, the Higgs boson may have far-reaching implications for the generation of the matter content in the Universe. For instance, the Higgs boson plays a key role in two main theories of baryogenesis, namely, electroweak baryogenesis and leptogenesis. In this Letter, we propose a new cosmological scenario where the Higgs chemical potential mediates asymmetries between visible and dark matter sectors, either generating a baryon asymmetry from a dark matter asymmetry or vice versa. We illustrate this mechanism with a simple model with two new fermions coupled to the Higgs boson and discuss the associated signatures.

Fibromyalgia and Complementary Health Approaches

Science.gov (United States)

... Musculoskeletal and Skin Diseases Web site . What the Science Says About Complementary Health Approaches for Fibromyalgia Mind ... Complementary and alternative medical therapies in fibromyalgia . Current Pharmaceutical Design . 2006;12(1):47–57. Sherman KJ, ...

Decision making in noisy bistable systems with time-dependent asymmetry

Science.gov (United States)

Nené, Nuno R.; Zaikin, Alexey

2013-01-01

Our work draws special attention to the importance of the effects of time-dependent parameters on decision making in bistable systems. Here, we extend previous studies of the mechanism known as speed-dependent cellular decision making in genetic circuits by performing an analytical treatment of the canonical supercritical pitchfork bifurcation problem with an additional time-dependent asymmetry and control parameter. This model has an analogous behavior to the genetic switch. In the presence of transient asymmetries and fluctuations, slow passage through the critical region in both systems increases substantially the probability of specific decision outcomes. We also study the relevance for attractor selection of reaching maximum values for the external asymmetry before and after the critical region. Overall, maximum asymmetries should be reached at an instant where the position of the critical point allows for compensation of the detrimental effects of noise in retaining memory of the transient asymmetries.

CP violating rate asymmetries in B decays ∑

Indian Academy of Sciences (India)

CP violating rate asymmetries in B decays. N G DESHPANDE. Institute of Theoretical Science, University of Oregon, Eugene, Oregon 97403-5203, USA. Email: desh@oregon.uoregon.edu. Abstract. We briefly discuss measurements of angles β and α of the unitarity triangle. We then review rate asymmetries using SU´3µ ...

Cerebral and non-cerebral coenurosis: on the genotypic and phenotypic diversity of Taenia multiceps.

Science.gov (United States)

Christodoulopoulos, Georgios; Dinkel, Anke; Romig, Thomas; Ebi, Dennis; Mackenstedt, Ute; Loos-Frank, Brigitte

2016-12-01

We characterised the causative agents of cerebral and non-cerebral coenurosis in livestock by determining the mitochondrial genotypes and morphological phenotypes of 52 Taenia multiceps isolates from a wide geographical range in Europe, Africa, and western Asia. Three studies were conducted: (1) a morphological comparison of the rostellar hooks of cerebral and non-cerebral cysts of sheep and goats, (2) a morphological comparison of adult worms experimentally produced in dogs, and (3) a molecular analysis of three partial mitochondrial genes (nad1, cox1, and 12S rRNA) of the same isolates. No significant morphological or genetic differences were associated with the species of the intermediate host. Adult parasites originating from cerebral and non-cerebral cysts differed morphologically, e.g. the shape of the small hooks and the distribution of the testes in the mature proglottids. The phylogenetic analysis of the mitochondrial haplotypes produced three distinct clusters: one cluster including both cerebral isolates from Greece and non-cerebral isolates from tropical and subtropical countries, and two clusters including cerebral isolates from Greece. The majority of the non-cerebral specimens clustered together but did not form a monophyletic group. No monophyletic groups were observed based on geography, although specimens from the same region tended to cluster. The clustering indicates high intraspecific diversity. The phylogenetic analysis suggests that all variants of T. multiceps can cause cerebral coenurosis in sheep (which may be the ancestral phenotype), and some variants, predominantly from one genetic cluster, acquired the additional capacity to produce non-cerebral forms in goats and more rarely in sheep.

Origins of the di-jet asymmetry in heavy ion collisions

CERN Document Server

Milhano, José Guilherme

2016-01-01

The di-jet asymmetry --- the measure of the momentum imbalance in a di-jet system --- is a key jet quenching observable. Using the event generator \\jewel we show that the di-jet asymmetry is dominated by fluctuations both in proton-proton and in heavy ion collisions. We discuss how in proton-proton collisions the asymmetry is generated through recoil and out-of-cone radiation. In heavy ion collisions two additional sources contribute to the asymmetry, namely energy loss fluctuations and differences in path length. The latter is shown to be a sub-leading effect. We discuss the implications of our results for the interpretation of this observable.

Origins of the di-jet asymmetry in heavy-ion collisions

Energy Technology Data Exchange (ETDEWEB)

Milhano, Jose Guilherme; Zapp, Korinna Christine [Universidade de Lisboa, CENTRA, Instituto Superior Tecnico, Lisbon (Portugal); CERN, Physics Department, Theory Unit, Geneva 23 (Switzerland)

2016-05-15

The di-jet asymmetry - the measure of the momentum imbalance in a di-jet system - is a key jet quenching observable. Using the event generator Jewel we show that the di-jet asymmetry is dominated by fluctuations both in proton-proton and in heavy-ion collisions. We discuss how in proton-proton collisions the asymmetry is generated through recoil and out-of-cone radiation. In heavy-ion collisions two additional sources can contribute to the asymmetry, namely energy loss fluctuations and differences in path length. The latter is shown to be a sub-leading effect. We discuss the implications of our results for the interpretation of this observable. (orig.)

Cerebral Palsy. Fact Sheet = La Paralisis Cerebral. Hojas Informativas Sobre Discapacidades.

Science.gov (United States)

National Information Center for Children and Youth with Disabilities, Washington, DC.

This fact sheet on cerebral palsy is written in both English and Spanish. First, it provides a definition of cerebral palsy and considers various causes (e.g., an insufficient amount of oxygen reaching the fetal or newborn brain). The fact sheet then offers incidence figures and explains characteristics of the three main types of cerebral palsy:…

LHCb; Measurement of the forward-central $b \\bar{b}$ production asymmetry

CERN Multimedia

Salustino Guimarães, V

2013-01-01

CDF and D0 collaborations results suggests that the top-quark forward-backward production asymmetry is much larger than the Standard Model (SM) predictions. Measuring the $b \\bar{b}$ asymmetry production would provide constraint on the flavor structure of any model that attempts to explain the CDF and D0 results. A measurement of the forward-central (FC) $b\\bar{b}$ production asymmetry is presented based on the LHCb data collected in 2011 at $\\sqrt{s}$ = 7 TeV corresponding to an integrated luminosity of 1.0 fb$^{-1}$ using selected events that have two identified $b$ jets, one of which is flavor tagged by one muon with high momentum. The FC asymmetry is defined as \\begin{align} A^{b \\bar{b}}_{FC}=\\frac{N(\\Delta y > 0)-N(\\Delta y 0)+N(\\Delta y 100$ GeV the expected asymmetry is about $\\cal{O}$(0.1 %) where gluon fusion which has no asymmetry is less dominant at high mass.

Using ground reaction force to predict knee kinetic asymmetry following anterior cruciate ligament reconstruction.

Science.gov (United States)

Dai, B; Butler, R J; Garrett, W E; Queen, R M

2014-12-01

Asymmetries in sagittal plane knee kinetics have been identified as a risk factor for anterior cruciate ligament (ACL) re-injury. Clinical tools are needed to identify the asymmetries. This study examined the relationships between knee kinetic asymmetries and ground reaction force (GRF) asymmetries during athletic tasks in adolescent patients following ACL reconstruction (ACL-R). Kinematic and GRF data were collected during a stop-jump task and a side-cutting task for 23 patients. Asymmetry indices between the surgical and non-surgical limbs were calculated for GRF and knee kinetic variables. For the stop-jump task, knee kinetics asymmetry indices were correlated with all GRF asymmetry indices (P kinetic asymmetry indices were correlated with the peak propulsion vertical GRF and vertical GRF impulse asymmetry indices (P kinetic asymmetries and therefore may assist in optimizing rehabilitation outcomes and minimizing re-injury rates. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Microembolism after cerebral angiography

International Nuclear Information System (INIS)

Manaka, Hiroshi; Sakai, Hideki; Nagata, Izumi

2000-01-01

Acute microemboli are detected more precisely with the recently developed diffusion-weighted MR imaging (DWI). We happened to obtain 24 DWIs after 350 diagnostic cerebral angiographies in 1999. DWIs after cerebral angiographies showed bright lesions in 7 patients (28%), of whom 6 had no neurological symptoms after cerebral angiography. Seven of the 24 patients had risk factors for arteriosclerosis. Only one patient had embolic events due to angiography. Microemboli related to cerebral angiographies are inevitable in some patients. Most are silent, however, we should investigate the cause of microemboli and should make cerebral angiography safer. (author)

Brain metabolism in autism. Resting cerebral glucose utilization rates as measured with positron emission tomography

Energy Technology Data Exchange (ETDEWEB)

Rumsey, J.M.; Duara, R.; Grady, C.; Rapoport, J.L.; Margolin, R.A.; Rapoport, S.I.; Cutler, N.R.

1985-05-01

The cerebral metabolic rate for glucose was studied in ten men (mean age = 26 years) with well-documented histories of infantile autism and in 15 age-matched normal male controls using positron emission tomography and (F-18) 2-fluoro-2-deoxy-D-glucose. Positron emission tomography was completed during rest, with reduced visual and auditory stimulation. While the autistic group as a whole showed significantly elevated glucose utilization in widespread regions of the brain, there was considerable overlap between the two groups. No brain region showed a reduced metabolic rate in the autistic group. Significantly more autistic, as compared with control, subjects showed extreme relative metabolic rates (ratios of regional metabolic rates to whole brain rates and asymmetries) in one or more brain regions.

Brain metabolism in autism. Resting cerebral glucose utilization rates as measured with positron emission tomography

International Nuclear Information System (INIS)

Rumsey, J.M.; Duara, R.; Grady, C.; Rapoport, J.L.; Margolin, R.A.; Rapoport, S.I.; Cutler, N.R.

1985-01-01

The cerebral metabolic rate for glucose was studied in ten men (mean age = 26 years) with well-documented histories of infantile autism and in 15 age-matched normal male controls using positron emission tomography and (F-18) 2-fluoro-2-deoxy-D-glucose. Positron emission tomography was completed during rest, with reduced visual and auditory stimulation. While the autistic group as a whole showed significantly elevated glucose utilization in widespread regions of the brain, there was considerable overlap between the two groups. No brain region showed a reduced metabolic rate in the autistic group. Significantly more autistic, as compared with control, subjects showed extreme relative metabolic rates (ratios of regional metabolic rates to whole brain rates and asymmetries) in one or more brain regions

Complementary medicine in chronic pain treatment.

Science.gov (United States)

Simpson, Charles A

2015-05-01

This article discusses several issues related to therapies that are considered "complementary" or "alternative" to conventional medicine. A definition of "complementary and alternative medicine" (CAM) is considered in the context of the evolving health care field of complementary medicine. A rationale for pain physicians and clinicians to understand these treatments of chronic pain is presented. The challenges of an evidence-based approach to incorporating CAM therapies are explored. Finally, a brief survey of the evidence that supports several widely available and commonly used complementary therapies for chronic pain is provided. Copyright © 2015 Elsevier Inc. All rights reserved.

Birth Defects: Cerebral Palsy

Science.gov (United States)

... Loss > Birth defects & other health conditions > Cerebral palsy Cerebral palsy E-mail to a friend Please fill in ... this page It's been added to your dashboard . Cerebral palsy (also called CP) is a group of conditions ...

Employees with Cerebral Palsy

Science.gov (United States)

... Resources Home | Accommodation and Compliance Series: Employees with Cerebral Palsy (CP) By Eddie Whidden, MA Preface Introduction Information ... SOAR) at http://AskJAN.org/soar. Information about Cerebral Palsy (CP) What is CP? Cerebral palsy is a ...

Co-clustering directed graphs to discover asymmetries and directional communities.

Science.gov (United States)

Rohe, Karl; Qin, Tai; Yu, Bin

2016-10-21

In directed graphs, relationships are asymmetric and these asymmetries contain essential structural information about the graph. Directed relationships lead to a new type of clustering that is not feasible in undirected graphs. We propose a spectral co-clustering algorithm called di-sim for asymmetry discovery and directional clustering. A Stochastic co-Blockmodel is introduced to show favorable properties of di-sim To account for the sparse and highly heterogeneous nature of directed networks, di-sim uses the regularized graph Laplacian and projects the rows of the eigenvector matrix onto the sphere. A nodewise asymmetry score and di-sim are used to analyze the clustering asymmetries in the networks of Enron emails, political blogs, and the Caenorhabditis elegans chemical connectome. In each example, a subset of nodes have clustering asymmetries; these nodes send edges to one cluster, but receive edges from another cluster. Such nodes yield insightful information (e.g., communication bottlenecks) about directed networks, but are missed if the analysis ignores edge direction.

Communication Apprehension and Resting Alpha Range Asymmetry in the Anterior Cortex

Science.gov (United States)

Beatty, Michael J.; Heisel, Alan D.; Lewis, Robert J.; Pence, Michelle E.; Reinhart, Amber; Tian, Yan

2011-01-01

In this study, we examined the relationship between trait-like communication apprehension (CA) and resting alpha range asymmetry in the anterior cortex (AC). Although theory and research in cognitive neuroscience suggest that asymmetry in the AC constitutes a relatively stable, inborn, substrate of emotion, some studies indicate that asymmetry can…

Right-handed snakes: convergent evolution of asymmetry for functional specialization

OpenAIRE

Hoso, Masaki; Asami, Takahiro; Hori, Michio

2007-01-01

External asymmetry found in diverse animals bears critical functions to fulfil ecological requirements. Some snail-eating arthropods exhibit directional asymmetry in their feeding apparatus for foraging efficiency because dextral (clockwise) species are overwhelmingly predominant in snails. Here, we show convergence of directional asymmetry in the dentition of snail-eating vertebrates. We found that snakes in the subfamily Pareatinae, except for non-snail-eating specialists, have more teeth o...

Asymmetry of Stark-broadened Layman lines from laser-produced plasmas

International Nuclear Information System (INIS)

Joyce, R.F.; Woltz, L.A.; Hooper, C.F. Jr.

1986-01-01

This paper discusses three significant causes of spectral line asymmetry: the ion-quadrupole interaction, the quadratic Stark effect and fine structure splitting that are included in the calculation of Lyman line profiles emitted by highly-ionized hydrogenic radiators in a dense, hot plasma. The line asymmetries are shown to be strongly dependent on the plasma density, indicating that the asymmetry may be of use as a density diagnostic

Toroidal asymmetries in divertor impurity influxes in NSTX

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F. Scotti

2017-08-01

Full Text Available Toroidal asymmetries in divertor carbon and lithium influxes were observed in NSTX, due to toroidal differences in surface composition, tile leading edges, externally-applied three-dimensional (3D fields and toroidally-localized edge plasma modifications due to radio frequency heating. Understanding toroidal asymmetries in impurity influxes is critical for the evaluation of total impurity sources, often inferred from measurements with a limited toroidal coverage. The toroidally-asymmetric lithium deposition induced asymmetries in divertor lithium influxes. Enhanced impurity influxes at the leading edge of divertor tiles were the main cause of carbon toroidal asymmetries and were enhanced during edge localized modes. Externally-applied 3D fields led to strike point splitting and helical lobes observed in divertor impurity emission, but marginal changes to the toroidally-averaged impurity influxes. Power coupled to the scrape-off layer SOL plasma during radio frequency (RF heating of H-mode discharges enhanced impurity influxes along the non-axisymmetric divertor footprint of flux tubes connecting to plasma in front of the RF antenna.

Critical asymmetry in renormalization group theory for fluids.

Science.gov (United States)

Zhao, Wei; Wu, Liang; Wang, Long; Li, Liyan; Cai, Jun

2013-06-21

The renormalization-group (RG) approaches for fluids are employed to investigate critical asymmetry of vapour-liquid equilibrium (VLE) of fluids. Three different approaches based on RG theory for fluids are reviewed and compared. RG approaches are applied to various fluid systems: hard-core square-well fluids of variable ranges, hard-core Yukawa fluids, and square-well dimer fluids and modelling VLE of n-alkane molecules. Phase diagrams of simple model fluids and alkanes described by RG approaches are analyzed to assess the capability of describing the VLE critical asymmetry which is suggested in complete scaling theory. Results of thermodynamic properties obtained by RG theory for fluids agree with the simulation and experimental data. Coexistence diameters, which are smaller than the critical densities, are found in the RG descriptions of critical asymmetries of several fluids. Our calculation and analysis show that the approach coupling local free energy with White's RG iteration which aims to incorporate density fluctuations into free energy is not adequate for VLE critical asymmetry due to the inadequate order parameter and the local free energy functional used in the partition function.

Baryon asymmetry, dark matter and local baryon number

International Nuclear Information System (INIS)

Fileviez Pérez, Pavel; Patel, Hiren H.

2014-01-01

We propose a new mechanism to understand the relation between baryon and dark matter asymmetries in the universe in theories where the baryon number is a local symmetry. In these scenarios the B−L asymmetry generated through a mechanism such as leptogenesis is transferred to the dark matter and baryonic sectors through sphalerons processes which conserve total baryon number. We show that it is possible to have a consistent relation between the dark matter relic density and the baryon asymmetry in the universe even if the baryon number is broken at the low scale through the Higgs mechanism. We also discuss the case where one uses the Stueckelberg mechanism to understand the conservation of baryon number in nature.

A Statistical Model of Head Asymmetry in Infants with Deformational Plagiocephaly

DEFF Research Database (Denmark)

Lanche, Stéphanie; Darvann, Tron Andre; Ólafsdóttir, Hildur

2007-01-01

Deformational plagiocephaly is a term describing cranial asymmetry and deformation commonly seen in infants. The purpose of this work was to develop a methodology for assessment and modelling of head asymmetry. The clinical population consisted of 38 infants for whom 3-dimensional surface scans...... quantitative description of the asymmetry present in the dataset....

Targeted presurgical decompensation in patients with yaw-dependent facial asymmetry.

Science.gov (United States)

Kim, Kyung-A; Lee, Ji-Won; Park, Jeong-Ho; Kim, Byoung-Ho; Ahn, Hyo-Won; Kim, Su-Jung

2017-05-01

Facial asymmetry can be classified into the rolling-dominant type (R-type), translation-dominant type (T-type), yawing-dominant type (Y-type), and atypical type (A-type) based on the distorted skeletal components that cause canting, translation, and yawing of the maxilla and/or mandible. Each facial asymmetry type represents dentoalveolar compensations in three dimensions that correspond to the main skeletal discrepancies. To obtain sufficient surgical correction, it is necessary to analyze the main skeletal discrepancies contributing to the facial asymmetry and then the skeletal-dental relationships in the maxilla and mandible separately. Particularly in cases of facial asymmetry accompanied by mandibular yawing, it is not simple to establish pre-surgical goals of tooth movement since chin deviation and posterior gonial prominence can be either aggravated or compromised according to the direction of mandibular yawing. Thus, strategic dentoalveolar decompensations targeting the real basal skeletal discrepancies should be performed during presurgical orthodontic treatment to allow for sufficient skeletal correction with stability. In this report, we document targeted decompensation of two asymmetry patients focusing on more complicated yaw-dependent types than others: Y-type and A-type. This may suggest a clinical guideline on the targeted decompensation in patient with different types of facial asymmetries.

Effect of ST36 Acupuncture on Hyperventilation-Induced CO2 Reactivity of the Basilar and Middle Cerebral Arteries and Heart Rate Variability in Normal Subjects

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Sang-Ho Hyun

2014-01-01

Full Text Available This study was conducted to verify the effect of acupuncture on cerebral haemodynamics to provide evidence for the use of acupuncture treatment as a complementary therapy for the high-risk stroke population. The effect of ST36 acupuncture treatment on the hyperventilation-induced CO2 reactivity of the basilar and middle cerebral arteries was studied in 10 healthy male volunteers (mean age, 25.2 ± 1.5 years using a transcranial Doppler sonography with an interval of 1 week between measurements, and a portable ECG monitoring system was used to obtain ECG data simultaneously. The CO2 reactivity of the basilar and middle cerebral arteries increased significantly after ST36 acupuncture treatment, whereas the mean arterial blood pressure and pulse rate did not change significantly. The high-frequency power significantly increased after ST36 acupuncture treatment, and the percentage increase of high-frequency power correlated significantly with the percentage increase in the CO2 reactivity of the contralateral middle cerebral artery. These data suggest that ST36 acupuncture treatment increases CO2 reactivity, indicating improvement of vasodilatory potential of the cerebral vasculature to compensate for fluctuations caused by changes in external conditions. The increase in parasympathetic tone by ST36 acupuncture treatment is responsible for this therapeutic effect.

Oral contraceptive therapy modulates hemispheric asymmetry in spatial attention.

Science.gov (United States)

Cicinelli, Ettore; De Tommaso, Marina; Cianci, Antonio; Colacurci, Nicola; Rella, Leonarda; Loiudice, Luisa; Cicinelli, Maria Vittoria; Livrea, Paolo

2011-12-01

Functional cerebral asymmetries (FCAs) are known to fluctuate across the menstrual cycle. The visual line-bisection task administered to normally cycling women showed different patterns of the interhemispheric interactions during menses and the midluteal cycle phase. However, the contribution of estrogens and progestins hormones to this phenomenon is still unclear. The aim of our study was to show a variation of FCAs in women administered oral contraceptives (OCs) using the visual line-bisection task. Visual line-bisection task with three horizontal lines was administered to 36 healthy women taking a 21-day OC. Twenty-nine patients were right handed. The task was administered during OC intake (day 10) and at the end of the pill-free period. The right-handed women showed a significant leftward bias of veridical center on the first and third lines during OC intake compared with an opposite rightward bias during the pill-free period. The same phenomenon of contralateral deviation was observed in left-handed women on day 10 of OC intake. The results of this study confirm a hormonal modulation on interhemispheric interaction and suggest that OCs may improve the interhemispheric interaction reducing FCAs compared with the low hormone level period. This opens new insights in OC prescription and choice of administration schedule in order to improve cognitive performances. Copyright © 2011 Elsevier Inc. All rights reserved.

Mandibular asymmetry and the fourth dimension.

Science.gov (United States)

Kaban, Leonard B

2009-03-01

This paper represents more than 30 years of discussion and collaboration with Drs Joseph Murray and John Mulliken in an attempt to understand growth patterns over time (ie, fourth dimension) in patients with hemifacial microsomia (HFM). This is essential for the development of rational treatment protocols for children and adults with jaw asymmetry. Traditionally, HFM was thought of as a unilateral deformity, but it was recognized that 20% to 30% of patients had bilateral abnormalities. However, early descriptions of skeletal correction addressed almost exclusively lengthening of the short (affected) side of the face. Based on longitudinal clinical observations of unoperated HFM patients, we hypothesized that abnormal mandibular growth is the earliest skeletal manifestation and that restricted growth of the mandible plays a pivotal role in progressive distortion of both the ipsilateral and contralateral facial skeleton. This hypothesis explains the progressive nature of the asymmetry in patients with HFM and provides the rationale for surgical lengthening of the mandible in children to prevent end-stage deformity. During the past 30 years, we have learned that this phenomenon of progressive distortion of the adjacent and contralateral facial skeleton occurs with other asymmetric mandibular undergrowth (tumor resection, radiation therapy, or posttraumatic defects) and overgrowth (mandibular condylar hyperplasia) conditions. In this paper, I describe the progression of deformity with time in patients with mandibular asymmetry as a result of undergrowth and overgrowth. Understanding these concepts is critical for the development of rational treatment protocols for adults with end-stage asymmetry and for children to minimize secondary deformity.

The role of three-gluon correlation functions in the single spin asymmetry

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Beppu Hiroo

2015-01-01

Full Text Available We study the twist-3 three-gluon contribution to the single spin asymmetry in the light-hadron production in pp collision in the framework of the collinear factorization. We derive the corresponding cross section formula in the leading order with respect to the QCD coupling constant. We also present a numerical calculation of the asymmetry at the RHIC energy, using a model for the three-gluon correlation functions suggested by the asymmetry for the D-meson production at RHIC. We found that the asymmetries for the light-hadron and the jet productions are very useful to constrain the magnitude and form of the correlation functions. Since the three-gluon correlation functions shift the asymmetry for all kinds of hadrons in the same direction, it is unlikely that they become a main source of the asymmetry.

Karyotipic asymmetry of both wild and cultivated species of Pennisetum

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Vânia Helena Techio

2010-01-01

Full Text Available This study aimed the establishment of the relation between karyotipic asymmetry values obtained for different accessions of both wild and cultivated species of Pennisetum from Germplasm Bank of Embrapa Gado de Leite/Juiz de Fora-Minas Gerais State, Brazil. Conventional cell cycle synchronization protocols and Feulgen staining method were used to obtain metaphases plates. The wild-type accessions corresponded to the species P. setosum (2n=6x=54, P. nervosum (2n=4x=36, and P. orientale (2n=4x=36, and the cultivated to P. purpureum (2n=4x=28 and P. glaucum (2n=2x=14. No significant difference was found for the total length of chromosomes (p>0.05 among the species. The analysis of intra-chromosomal asymmetry (A1 and inter-chromosomal asymmetry (A2 has shown that P. setosum has a tendency to chromosome asymmetry. P. nervosum, P. orientale, and P. purpureum have presented an intermediary level of asymmetry and P. glaucum, low asymmetry. Considering Stebbins criteria, the karyotype of P. glaucum and those from the three wild species fitted into the category 1A-symmetrical. With regard to P. purpureum, karyotypes of the accessions BAGs 54, 65 and 91 fitted into the category 2B and the other two genotypes (BAGs 63 and 75 fitted into the 1A. Comparison between the karyotype classification according to the inter- and intra-chromosomal asymmetry and Stebbins methodologies revealed that this last one alone was not able to detect small variations between karyotypes of the taxa closely related.

Poloidal asymmetries of the heavy ions in the ASDEX Upgrade tokamak

Energy Technology Data Exchange (ETDEWEB)

Odstrcil, Tomas [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany); Physik-Department E28, Technische Universitaet Muenchen, Garching (Germany); Puetterich, Thomas; Angioni, Clemente; Bilato, Roberto; Gude, Anja; Vezinet, Didier [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany); Mazon, Didier [CEA, IRFM, Saint Paul-lez-Durance (France); Collaboration: ASDEX Upgrade Team

2015-05-01

Poloidal asymmetries of heavy ions in the tokamak plasma are caused by the presence of forces parallel with field-lines which have comparable magnitude to the thermal pressure. The most important examples are the centrifugal force (CF) and the electric force (EF). The CF is caused by fast toroidal rotation of the plasma column which is pushing impurity ions, that have a substantially higher mass than the main ions, on the outer-side of the plasma. And the EF can be produced by ion cyclotron heated fast particles with high pitch angle that are trapped by the mirror force on the low field side of the plasma. The excessive charge produced by these particles is affecting highly charged impurities and pushing them to the high field side of the plasma. From predictions based on neoclassical and turbulent theory, it follows that the radial flux of heavy ions will be significantly changed by the presence of these asymmetries. The purpose of this study is to investigate the presence of these asymmetries in ASDEX Upgrade and verify the predicted consequences on the particles flux. High intrinsic content of the tungsten in AUG plasma makes this device well suitable for such studies. Precise measurement of the SXR (soft-X-ray) radiation profiles has identified a presence of CF generated asymmetries in every NBI heated Asdex discharge. Poloidal asymmetry should than lead to the significant change in the neoclassical and turbulent radial transport of these heavy ions. High intrinsic content of the tungsten in Asdex plasma makes this device well suitable for studying these asymmetries. Precise measurement of the SXR (soft-X-ray) radiation profiles has identified a presence of CF generated asymmetries in every NBI heated Asdex discharge. For heavy and highly charged impurities multiple mechanisms exist that produce non-constant impurities densities on the flux surfaces. As for neoclassical and turbulent transport models such an asymmetry is of highly importance an effort is

Hypothermia reduces cerebral metabolic rate and cerebral blood flow in newborn pigs

International Nuclear Information System (INIS)

Busija, D.W.; Leffler, C.W.

1987-01-01

The authors examined effects of hypothermia on cerebral metabolic rate and cerebral blood flow in anesthetized, newborn pigs (1-4 days old). Cerebral blood flow (CBF) was determined with 15-μm radioactive microspheres. Regional CBF ranged from 44 to 66 ml·min -1 ·100 g -1 , and cerebral metabolic rate was 1.94 ± 0.23 ml O 2 ·100 g -1 ·min -1 during normothermia (39 degree C). Reduction of rectal temperature to 34-35 degree C decreased CBF and cerebral metabolic rate 40-50%. In another group of piglets, they examined responsiveness of the cerebral circulation to arterial hypercapnia during hypothermia. Although absolute values for normocapnic and hypercapnic CBF were reduced by hypothermia and absolute values for normocapnic and hypercapnic cerebrovascular resistance were increased, the percentage changes from control in these variables during hypercapnia were similar during normothermia and hypothermia. In another group of animals that were maintained normothermic and exposed to two episodes of hypercapnia, there was no attenuation of cerebrovascular dilation during the second episode. They conclude that hypothermia reduces CBF secondarily to a decrease in cerebral metabolic rate and that percent dilator responsiveness to arterial hypercapnia is unaltered when body temperature is reduced

Assimetria cerebral e lateralização da linguagem: déficits nucleares na esquizofrenia como indicadores da predisposição genética Asimetría cerebral y lateralización del lenguaje: déficits nucleares en la esquizofrenia como indicadores de predisposición genética Cerebral asymmetry and the lateralization of language: core deficits in schizophrenia as pointers to the genetic predisposition

Directory of Open Access Journals (Sweden)

Timothy J. Crow

2004-08-01

anatómicos, funcionales y genéticos. HALLAZGOS RECIENTES: Estudios de imagen, post mortem y anatómicos, demuestran evidencias de una reducción o reversión de aspectos de asimetría, particularmente en la corteza de asociación occipito-temporo-parietal. En algunos estudios, hay interacción con el sexo. Hay evidencias de que una alteración en el lóbulo temporal izquierdo es, a veces, progresiva. Estudios funcionales agregan credibilidad al concepto de que la lateralización del lenguaje es reducida y, en algunos casos, revertida. RESUMEN: La dimensión de la asimetría se destaca como la variable que puede dar significación a las observaciones entre campos de investigación y que proporciona una solución para la base genética de la psicosis. Estudios de gemelos monocigóticos discordantes vienen presentando fuertes indicaciones de que la variación relevante es epigenética; ello es consistente con la posibilidad de que la variación esté relacionada a alteraciones estructurales recientes (la trasposición replicativa Xq21.3/Yp de los cromosomas sexuales.PURPOSE OF REVIEW: Cerebral asymmetry (the torque from right frontal to left occipital is the defining feature of the human brain, and as Broca proposed, the putative neural correlate of language. If as has been suggested schizophrenia is the price that Homo sapiens pays for language, the torque together with its functional correlates is of central significance. Recent evidence from anatomical, functional and genetic studies is reviewed. RECENT FINDINGS: Both post-mortem and anatomical imaging studies show evidence of a reduction or reversal of aspects of asymmetry particularly in the occipito-temporo-parietal association cortex. In some studies there is an interaction with sex. There is evidence that change in the left temporal lobe is sometimes progressive. Functional studies add substance to the concept that the lateralization of language is reduced and in some aspects reversed. SUMMARY: The dimension of

New views on strand asymmetry in insect mitochondrial genomes.

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Shu-Jun Wei

Full Text Available Strand asymmetry in nucleotide composition is a remarkable feature of animal mitochondrial genomes. Understanding the mutation processes that shape strand asymmetry is essential for comprehensive knowledge of genome evolution, demographical population history and accurate phylogenetic inference. Previous studies found that the relative contributions of different substitution types to strand asymmetry are associated with replication alone or both replication and transcription. However, the relative contributions of replication and transcription to strand asymmetry remain unclear. Here we conducted a broad survey of strand asymmetry across 120 insect mitochondrial genomes, with special reference to the correlation between the signs of skew values and replication orientation/gene direction. The results show that the sign of GC skew on entire mitochondrial genomes is reversed in all species of three distantly related families of insects, Philopteridae (Phthiraptera, Aleyrodidae (Hemiptera and Braconidae (Hymenoptera; the replication-related elements in the A+T-rich regions of these species are inverted, confirming that reversal of strand asymmetry (GC skew was caused by inversion of replication origin; and finally, the sign of GC skew value is associated with replication orientation but not with gene direction, while that of AT skew value varies with gene direction, replication and codon positions used in analyses. These findings show that deaminations during replication and other mutations contribute more than selection on amino acid sequences to strand compositions of G and C, and that the replication process has a stronger affect on A and T content than does transcription. Our results may contribute to genome-wide studies of replication and transcription mechanisms.

Perceptual asymmetry in texture perception.

Science.gov (United States)

Williams, D; Julesz, B

1992-07-15

A fundamental property of human visual perception is our ability to distinguish between textures. A concerted effort has been made to account for texture segregation in terms of linear spatial filter models and their nonlinear extensions. However, for certain texture pairs the ease of discrimination changes when the role of figure and ground are reversed. This asymmetry poses a problem for both linear and nonlinear models. We have isolated a property of texture perception that can account for this asymmetry in discrimination: subjective closure. This property, which is also responsible for visual illusions, appears to be explainable by early visual processes alone. Our results force a reexamination of the process of human texture segregation and of some recent models that were introduced to explain it.

Proton GE/GM from beam-target asymmetry

International Nuclear Information System (INIS)

Mark Jones; Aram Aghalaryan; Abdellah Ahmidouch; Razmik Asaturyan; Frederic Bloch; Werner Boeglin; Peter Bosted; Cedric Carasco; Roger Carlini; Jinseok Cha; Jian-Ping Chen; Michael Christy; Leon Cole; Luminita Coman; Donald Crabb; Samuel Danagoulian; Donal Day; James Dunne; Mostafa Elaasar; Rolf Ent; Howard Fenker; Emil Frlez; David Gaskell; Liping Gan; Javier Gomez; Bitao Hu; Juerg Jourdan; Christopher Keith; Cynthia Keppel; Mahbubul Khandaker; Andreas Klein; Laird Kramer; Yongguang Liang; Jechiel Lichtenstadt; Richard Lindgren; David Mack; Paul McKee; Dustin McNulty; David Meekins; Hamlet Mkrtchyan; Rakhsha Nasseripour; Maria-Ioana Niculescu; Kristoff Normand; Blaine Norum; Dinko Pocanic; Yelena Prok; Brian Raue; Joerg Reinhold; Julie Roche; Daniela Rohe; Oscar Rondon-Aramayo; Nikolai Savvinov; Bradley Sawatzky; Mikell Seely; Ingo Sick; Karl Slifer; C. Smith; Gregory Smith; S. Stepanyan; Liguang Tang; Shigeyuki Tajima; Giuseppe Testa; William Vulcan; Kebin Wang; Glen Warren; Frank Wesselmann; Stephen Wood; Chen Yan; Lulin Yuan; Junho Yun; Markus Zeier; Hong Guo Zhu

2006-01-01

The ratio of the proton's electric to magnetic form factor, G E /G M , can be extracted in elastic electron-proton scattering by measuring either cross sections, beam-target asymmetry or recoil polarization. Separate determinations of G E /G M by cross sections and recoil polarization observables disagree for Q 2 > 1 (GeV/c) 2 . Measurement by a third technique might uncover an unknown systematic error in either of the previous measurements. The beam-target asymmetry has been measured for elastic electron-proton scattering at Q 2 = 1.51 (GeV/c) 2 for target spin orientation aligned perpendicular to the beam momentum direction. This is the largest Q 2 at which G E /G M has been determined by a beam-target asymmetry experiment. The result, μG E /G M = 0.884 +/- 0.027 +/- 0.029, is compared to previous world data

A study of acetazolamide-induced changes in cerebral blood flow using {sup 99m}Tc HMPAO SPECT in patients with cerebrovascular disease

Energy Technology Data Exchange (ETDEWEB)

Asenbaum, S. [Neurological Clinic, Univ. Vienna (Austria); Reinprecht, A. [Neurosurgical Clinic, Univ. Vienna (Austria); Bruecke, T. [Neurological Clinic, Univ. Vienna (Austria); Wenger, S. [Neurological Clinic, Univ. Vienna (Austria); Podreka, I. [Neurological Clinic, Univ. Vienna (Austria); Deecke, L. [Neurological Clinic, Univ. Vienna (Austria)

1995-01-01

For semiquantification of SPECT studies we tried to calculate cerebral {sup 99m}Tc-HMPAO uptake related to injected dose and estimated brain volume. The method was applied to SPECT investigations of 27 patients who had a least one ischaemic attack and a confirmed 80-100% stenosis of the corresponding internal carotid artery (ICA). Vascular reactivity was tested by parenteral administration of acetazolamide (AZ). Increase in HMPAO uptake after AZ was evident in both hemispheres, although the increase (AZ effect) was significantly lower in the affected hemisphere (+24% versus +28%). No interhemispheric uptake differences were seen in patients with largely normal SPECT studies, although local asymmetries in HMPAO deposition were visible. Patients with low density lesions on CT and with a well-demarcated lesion in the same location on SPECT revealed interhemispheric uptake differences, with lower uptake on the affected side. This was not due solely to alterations in the lesion, but also to reduced HMPAO uptake and AZ effect in the surrounding area. The AZ effect showed no correlation with angiographic findings, indicating no major haemodynamic influence of the ICA stenosis on cerebral hemisphere perfusion. Calculated cerebral HMPAO uptake changes after AZ administration were in good accordance with absolute cerebral blood flow measurements, and made interindividual comparisons possible. However, as changes in the area around an infarct or local reduction in vascular reserve may not be reproduced adequately by uptake calculations, visual inspection is still necessary. (orig.)

Hyperventilation, cerebral perfusion, and syncope

DEFF Research Database (Denmark)

Immink, R V; Pott, F C; Secher, N H

2014-01-01

dioxide (PaCO2) and oxygen (PaO2) partial pressures so that hypercapnia/hypoxia increases and hypocapnia/hyperoxia reduces global cerebral blood flow. Cerebral hypoperfusion and TLOC have been associated with hypocapnia related to HV. Notwithstanding pronounced cerebrovascular effects of PaCO2...... the contribution of a low PaCO2 to the early postural reduction in middle cerebral artery blood velocity is transient. HV together with postural stress does not reduce cerebral perfusion to such an extent that TLOC develops. However when HV is combined with cardiovascular stressors like cold immersion or reduced...... cardiac output brain perfusion becomes jeopardized. Whether, in patients with cardiovascular disease and/or defect, cerebral blood flow cerebral control HV-induced hypocapnia elicits cerebral hypoperfusion, leading to TLOC, remains to be established....

Flavor versus mass eigenstates in neutrino asymmetries: implications for cosmology

Energy Technology Data Exchange (ETDEWEB)

Barenboim, Gabriela [Universitat de Valencia-CSIC, Departament de Fisica Teorica y IFIC, Burjassot (Spain); Kinney, William H. [University at Buffalo, Department of Physics, Buffalo, NY (United States); Park, Wan-Il [Universitat de Valencia-CSIC, Departament de Fisica Teorica y IFIC, Burjassot (Spain); Chonbuk National University, Division of Science Education and Institute of Fusion Science, Jeonju (Korea, Republic of)

2017-09-15

We show that, if they exist, lepton number asymmetries (L{sub α}) of neutrino flavors should be distinguished from the ones (L{sub i}) of mass eigenstates, since Big Bang Nucleosynthesis (BBN) bounds on the flavor eigenstates cannot be directly applied to the mass eigenstates. Similarly, Cosmic Microwave Background (CMB) constraints on the mass eigenstates do not directly constrain flavor asymmetries. Due to the difference of mass and flavor eigenstates, the cosmological constraint on the asymmetries of neutrino flavors can be much stronger than the conventional expectation, but they are not uniquely determined unless at least the asymmetry of the heaviest neutrino is well constrained. The cosmological constraint on L{sub i} for a specific case is presented as an illustration. (orig.)

Mass loss and asymmetries in the lines of Iota Coronae Borealis

International Nuclear Information System (INIS)

Kapp, A.H.

1976-01-01

Recent observations by Smith and Parsons of the Hg--Mn star iota CrB have revealed slight asymmetries in the absorption lines. While these asymmetries are near the limits of detection at the resolution used, their appearance in several lines indicates that they are real. Proposed explanations of this phenomenon are not completely satisfactory. In this Letter it will be shown that the asymmetries are consistent with an accelerating radial flow of material in the photosphere of this star. The velocity needed to reproduce the observed asymmetry corresponds to a mass loss rate of roughly 10 -7 M/sub solar mass/ yr -1

Measurement of the Collins and Sivers asymmetries on transversely polarised protons

CERN Document Server

Alekseev, M.G.; Alexandrov, Yu.; Alexeev, G.D.; Amoroso, A.; Austregesilo, A.; Badelek, B.; Balestra, F.; Ball, J.; Barth, J.; Baum, G.; Bedfer, Y.; Bernhard, J.; Bertini, R.; Bettinelli, M.; Birsa, R.; Bisplinghoff, J.; Bordalo, P.; Bradamante, F.; Bravar, A.; Bressan, A.; Brona, G.; Burtin, E.; Bussa, M.P.; Chaberny, D.; Chiosso, M.; Chung, S.U.; Cicuttin, A.; Colantoni, M.; Crespo, M.L.; Dalla Torre, S.; Das, S.; Dasgupta, S.S.; Denisov, O.Yu.; Dhara, L.; Diaz, V.; Donskov, S.V.; Doshita, N.; Duic, V.; Dunnweber, W.; Efremov, A.; El Alaoui, A.; Elia, C.; Eversheim, P.D.; Eyrich, W.; Faessler, M.; Ferrero, A.; Filin, A.; Finger, M.; Finger, M., jr.; Fischer, H.; Franco, C.; Friedrich, J.M.; Garfagnini, R.; Gautheron, F.; Gavrichtchouk, O.P.; Gazda, R.; Gerassimov, S.; Geyer, R.; Giorgi, M.; Gnesi, I.; Gobbo, B.; Goertz, S.; Grabmuller, S.; Grasso, A.; Grube, B.; Gushterski, R.; Guskov, A.; Haas, F.; von Harrach, D.; Hasegawa, T.; Heinsius, F.H.; Hermann, R.; Herrmann, F.; Hess, C.; Hinterberger, F.; Horikawa, N.; Hoppner, Ch.; d'Hose, N.; Ilgner, C.; Ishimoto, S.; Ivanov, O.; Ivanshin, Yu.; Iwata, T.; Jahn, R.; Jasinski, P.; Jegou, G.; Joosten, R.; Kabuss, E.; Kafer, W.; Kang, D.; Ketzer, B.; Khaustov, G.V.; Khokhlov, Yu.A.; Kiefer, J.; Kisselev, Yu.; Klein, F.; Klimaszewski, K.; Koblitz, S.; Koivuniemi, J.H.; Kolosov, V.N.; Komissarov, E.V.; Kondo, K.; Konigsmann, K.; Konopka, R.; Konorov, I.; Konstantinov, V.F.; Korzenev, A.; Kotzinian, A.M.; Kouznetsov, O.; Kowalik, K.; Kramer, M.; Kral, A.; Kroumchtein, Z.V.; Kuhn, R.; Kunne, F.; Kurek, K.; Lauser, L.; Le Goff, J.M.; Lednev, A.A.; Lehmann, A.; Levorato, S.; Lichtenstadt, J.; Liska, T.; Maggiora, A.; Maggiora, M.; Magnon, A.; Mallot, G.K.; Mann, A.; Marchand, C.; Martin, A.; Marzec, J.; Massmann, F.; Matsuda, T.; Meyer, W.; Michigami, T.; Mikhailov, Yu.V.; Moinester, M.A.; Mutter, A.; Nagaytsev, A.; Nagel, T.; Nassalski, J.; Negrini, T.; Nerling, F.; Neubert, S.; Neyret, D.; Nikolaenko, V.I.; Nunes, A.S.; Olshevsky, A.G.; Ostrick, M.; Padee, A.; Panknin, R.; Panzieri, D.; Parsamyan, B.; Paul, S.; Pawlukiewicz-Kaminska, B.; Perevalova, E.; Pesaro, G.; Peshekhonov, D.V.; Piragino, G.; Platchkov, S.; Pochodzalla, J.; Polak, J.; Polyakov, V.A.; Pontecorvo, G.; Pretz, J.; Quintans, C.; Rajotte, J.-F.; Ramos, S.; Rapatsky, V.; Reicherz, G.; Richter, A.; Robinet, F.; Rocco, E.; Rondio, E.; Ryabchikov, D.I.; Samoylenko, V.D.; Sandacz, A.; Santos, H.; Sapozhnikov, M.G.; Sarkar, S.; Savin, I.A.; Sbrizza, G.; Schiavon, P.; Schill, C.; Schluter, T.; Schmitt, L.; Schopferer, S.; Schroder, W.; Shevchenko, O.Yu.; Siebert, H.-W.; Silva, L.; Sinha, L.; Sissakian, A.N.; Slunecka, M.; Smirnov, G.I.; Sosio, S.; Sozzi, F.; Srnka, A.; Stolarski, M.; Sulc, M.; Sulej, R.; Takekawa, S.; Tessaro, S.; Tessarotto, F.; Teufel, A.; Tkatchev, L.G.; Uhl, S.; Uman, I.; Virius, M.; Vlassov, N.V.; Vossen, A.; Weitzel, Q.; Windmolders, R.; Wislicki, W.; Wollny, H.; Zaremba, K.; Zavertyaev, M.; Zemlyanichkina, E.; Ziembicki, M.; Zhao, J.; Zhuravlev, N.; Zvyagin, A.

2010-01-01

The Collins and Sivers asymmetries for charged hadrons produced in deeply inelastic scattering on transversely polarised protons have been extracted from the data collected in 2007 with the CERN SPS muon beam tuned at 160 GeV/c. At large values of the Bjorken x variable non-zero Collins asymmetries are observed both for positive and negative hadrons while the Sivers asymmetry for positive hadrons is slightly positive over almost all the measured x range. These results nicely support the present theoretical interpretation of these asymmetries, in terms of leading-twist quark distribution and fragmentation functions.

Matter-antimatter asymmetry

Energy Technology Data Exchange (ETDEWEB)

NONE

2002-07-01

The Conference is devoted to a multidisciplinary study of matter-antimatter asymmetry and, in particular, from the point of view of particle physics, astrophysics and cosmology. A number of topics, such as the practical applications of antimatter in medical imaging, of particular interest to non-specialists, will also be briefly covered. More than thirty years after the discovery of CP violation in the kaon system, precision experiments with kaons at CERN and Fermilab have demonstrated the existence of direct CP violation, opening a window on a hitherto poorly explored part of particle physics. On the one hand, two experiments devoted mainly to CP violation in B mesons, BABAR and Belle, are beginning to test CP violation in the Standard Model in a decisive way. On the other hand, balloon experiments and the space-based AMS project are circumscribing precise limits on the cosmological abundance of antimatter. Finally, the fundamental problem of cosmological matter-antimatter asymmetry at a Grand Unification scale or at the Electroweak phase transition has been the object of intense theoretical activity in recent years. This document gathers most of the slides that have been presented in the plenary and parallel sessions.

Event-related frontal alpha asymmetries: electrophysiological correlates of approach motivation.

Science.gov (United States)

Schöne, Benjamin; Schomberg, Jessica; Gruber, Thomas; Quirin, Markus

2016-02-01

Over the last decades, frontal alpha asymmetries observed during resting state periods of several minutes have been used as a marker of affective-motivational states. To date, there is no evidence that alpha asymmetries can be observed in response to brief affective-motivational stimuli, as typically presented in event-related designs. As we argue, frontal alpha asymmetry might indeed be elicited by brief events if they are salient enough. In an event-related design, we used erotic pictures, i.e., highly salient incentives to elicit approach motivation, and contrasted them with pictures of dressed attractive women. As expected, we found significant alpha asymmetries for erotic pictures as compared to control pictures. Our findings suggest that the highly reactive reward system can lead to immediate, phasic changes in frontal alpha asymmetries. We discuss the findings with respect to the notion that high salience of erotic pictures derives from their potential of satisfying an individuals' need by mere visual inspection, which is not the case for pictures showing other types of motivational stimuli such as food.

Cerebral perfusion MR imaging using FAIR-HASTE in chronic carotid occlusive disease. Comparison with dynamic susceptibility contrast-perfusion MR imaging

International Nuclear Information System (INIS)

Ida, Kentaro; Akaki, Shiro; Sei, Tetsuro; Kanazawa, Susumu; Tsunoda, Masatoshi

2006-01-01

To determine the efficacy of flow-sensitive alternating inversion recovery using half-Fourier single-shot turbo spin-echo (FAIR-HASTE) in detecting cerebral hypoperfusion in chronic carotid occlusive disease, we subjected 12 patients with various degrees of cervical internal carotid artery stenoses and/or occlusion (Stenosis group) and 24 volunteers (Normal group) to FAIR-HASTE. In addition, 10 out of 12 patients in the Stenosis group underwent dynamic susceptibility contrast-perfusion magnetic resonance imaging (DSC-pMRI) before and after revascularization in the dominantly affected side. The absolute asymmetry indexes (AIs) of both cerebral hemispheres in the Normal and Stenosis groups were compared in FAIR-HASTE. In addition, the AIs were compared with those in the Stenosis group before and after revascularization in both FAIR-HASTE and regional cerebral blood flow (rCBF), calculated with DSC-pMRI. A statistically significant difference was recognized between the AIs in the Normal and Stenosis groups (AI=2.25±1.92, 8.09±4.60, respectively; p<0.0001). Furthermore, in the Stenosis group the AIs on both FAIR-HASTE (8.88±4.93, 2.22±1.79, respectively; p=0.0003) and rCBF (7.13±3.57, 1.25±1.33, respectively; p=0.0003) significantly decreased after revascularization. In the Stenosis group, before revascularization, signal intensity on both FAIR-HASTE and rCBF had a tendency to be lower in the dominantly affected side. FAIR-HASTE imaging was useful in the detection and evaluation of cerebral hypoperfusion in chronic occlusive carotid disease. (author)

Detection symmetry and asymmetry

NARCIS (Netherlands)

du Buf, J.M.H.

1991-01-01

Experiments were performed on the detection symmetry and asymmetry of incremental and decremental disks, as a function of both disk diameter and duration. It was found that, for a background luminance of 300cd.m-2, thresholds of dynamic (briefly presented) foveal disks are symmetrical for all

European economic integration and (A)symmetry of macroeconomic fluctuations

NARCIS (Netherlands)

Kool, C.J.M.; Economidou, C.

2007-01-01

This paper empirically investigates output and consumption asymmetries in the Eurozone and enlarged EU over the period 1992-2007, and their consequences for monetary policy. Our results reveal that the introduction of the euro has little impact on output asymmetry so far; however, it has led to

Spatial asymmetry of post-stroke hemiparetic gait: assessment and ...

African Journals Online (AJOL)

Despite potential benefits, quantitative analysis of gait asymmetry is still not routinely used in many hospitals and rehabilitation institutions in developing countries due to ... Conclusion: Overall, the study demonstrated asymmetry of step length and foot rotation angle during walking of post-stroke hemiparetic individuals and ...

Main effect and interactions of brain regions and gender in the calculation of volumetric asymmetry indices in healthy human brains: ANCOVA analyses of in vivo 3T MRI data.

Science.gov (United States)

Roldan-Valadez, Ernesto; Rios, Camilo; Suarez-May, Marcela A; Favila, Rafel; Aguilar-Castañeda, Erika

2013-12-01

Macroanatomical right-left hemispheric differences in the brain are termed asymmetries, although there is no clear information on the global influence of gender and brain-regions. The aim of this study was to evaluate the main effects and interactions of these variables on the measurement of volumetric asymmetry indices (VAIs). Forty-seven healthy young-adult volunteers (23 males, 24 females) agreed to undergo brain magnetic resonance imaging in a 3T scanner. Image post processing using voxel-based volumetry allowed the calculation of 54 VAIs from the frontal, temporal, parietal and occipital lobes, limbic system, basal ganglia, and cerebellum for each cerebral hemisphere. Multivariate ANCOVA analysis calculated the main effects and interactions on VAIs of gender and brain regions controlling the effect of age. The only significant finding was the main effect of brain regions (F (6, 9373.605) 44.369, P gender and brain regions (F (6, 50.517) .239, P = .964). Volumetric asymmetries are present across all brain regions, with larger values found in the limbic system and parietal lobe. The absence of a significant influence of gender and age in the evaluation of the numerous measurements generated by multivariate analyses in this study should not discourage researchers to report and interpret similar results, as this topic still deserves further assessment. Copyright © 2013 Wiley Periodicals, Inc.

On the conception of fundamental time asymmetries in physics

Energy Technology Data Exchange (ETDEWEB)

Wohlfarth, Daniel

2013-02-05

The investigation is divided in 7 chapters and aims to argue for the realizability of a new conception of 'fundamental time asymmetries' in physics. After an introduction (chapter 1) in the field of interest, the investigation continues by developing a conception of fundamentality for time asymmetries in chapter 2. Chapter 3 shows that this conception is realized in classical cosmology and chapter 4 demonstrates, by taking in to account the result from chapter 3, that classical electrodynamics is understandable as a time asymmetric theory. Chapter 5 focuses on time asymmetries in quantum cosmology as well as quantum thermodynamics and demonstrates - as in the classical case - that a fundamental time asymmetry is imbedded in those fields. The considerations, contained in chapter 6, are focused on non relativistic quantum mechanics (NRQM). Here the main aim is to demonstrate that NRQM can be understood as a time asymmetric theory - even without using the measurement-process for that purpose. Chapter 7 summarized the main arguments and conclusions.

On the conception of fundamental time asymmetries in physics

International Nuclear Information System (INIS)

Wohlfarth, Daniel

2013-01-01

The investigation is divided in 7 chapters and aims to argue for the realizability of a new conception of 'fundamental time asymmetries' in physics. After an introduction (chapter 1) in the field of interest, the investigation continues by developing a conception of fundamentality for time asymmetries in chapter 2. Chapter 3 shows that this conception is realized in classical cosmology and chapter 4 demonstrates, by taking in to account the result from chapter 3, that classical electrodynamics is understandable as a time asymmetric theory. Chapter 5 focuses on time asymmetries in quantum cosmology as well as quantum thermodynamics and demonstrates - as in the classical case - that a fundamental time asymmetry is imbedded in those fields. The considerations, contained in chapter 6, are focused on non relativistic quantum mechanics (NRQM). Here the main aim is to demonstrate that NRQM can be understood as a time asymmetric theory - even without using the measurement-process for that purpose. Chapter 7 summarized the main arguments and conclusions.

Tidal asymmetry in a funnel-shaped estuary with mixed semidiurnal tides

Science.gov (United States)

Gong, Wenping; Schuttelaars, Henk; Zhang, Heng

2016-05-01

Different types of tidal asymmetry (see review of de Swart and Zimmerman Annu Rev Fluid Mech 41: 203-229, 2009) are examined in this study. We distinguish three types of tidal asymmetry: duration and magnitude differences between flood and ebb tidal flow, duration difference between the rising and falling tides. For waterborne substance transport, the first two asymmetries are important while the last one is not. In this study, we take the Huangmaohai Estuary (HE), Pearl River Delta, China as an example to examine the spatio-temporal variations of the tidal asymmetry in a mixed semidiurnal tidal regime and to explain them by investigating the associated mechanisms. The methodology defining the tidal duration asymmetry and velocity skewness, proposed by Nidzieko (J Geophys Res 115: C08006. doi: 10.1029/2009JC005864 , 2010) and synthesized by Song et al. (J Geophys Res 116: C12007. doi: 10.1029/2011JC007270 , 2011), is utilized here and referred to as tidal duration asymmetry (TDA) and flow velocity asymmetry (FVA), respectively. The methodology is further used to quantify the flow duration asymmetry (FDA). A positive asymmetry means a shorter duration of low water slack for FDA, a shorter duration of the rising tide for TDA, and a flood dominance for FVA and vice versa. The Regional Ocean Modeling System (ROMS) model is used to provide relatively long-term water elevation and velocity data and to conduct diagnostic experiments. In the HE, the main tidal constituents are diurnal tides K 1, O 1 and semidiurnal tides M 2 and S 2. The interaction among the diurnal and semidiurnal tides generates a negative tidal asymmetry, while the interactions among semidiurnal tides and their overtides or compound tides result in a positive tidal asymmetry. The competition among the above interactions determines the FDA and TDA, whereas for the FVA, aside from the interaction among different tidal constituents, an extra component, the residual flow, plays an important role. The

Disentangling the Relationship between Hemispheric Asymmetry and Cognitive Performance

Science.gov (United States)

Hirnstein, Marco; Leask, Stuart; Rose, Jonas; Hausmann, Markus

2010-01-01

It is widely believed that advantages of hemispheric asymmetries originated in better cognitive processing, hence it is often implied that the relationship between hemispheric asymmetry and cognitive performance is linearly positive: the higher the degree of lateralization in a specific cognitive domain, the better the performance in a…

Frontal alpha EEG asymmetry before and after behavioral activation treatment for depression.

Science.gov (United States)

Gollan, Jackie K; Hoxha, Denada; Chihade, Dietta; Pflieger, Mark E; Rosebrock, Laina; Cacioppo, John

2014-05-01

Mid-frontal and mid-lateral (F3/F4 and F7/F8) EEG asymmetry has been associated with motivation and affect. We examined alpha EEG asymmetry in depressed and healthy participants before and after Behavioral Activation treatment for depression; examined the association between alpha EEG asymmetry and motivational systems and affect; and evaluated the utility of alpha EEG asymmetry in predicting remission. Depressed (n=37) and healthy participants (n=35) were assessed before and after treatment using a clinical interview, a task to measure baseline EEG, and questionnaires of behavioral activation and inhibition, avoidance, and affect. Alpha EEG asymmetry was significantly higher in depressed than healthy participants at pre-treatment, positively correlated with negative affect and behavioral inhibition, and inversely correlated with lower behavioral activation sensitivity. Heightened alpha EEG asymmetry in depressed participants was significantly associated with increased behavioral inhibition and negative emotion and was independent of clinical remission. Copyright © 2014 Elsevier B.V. All rights reserved.

Frontal alpha asymmetry neurofeedback for the reduction of negative affect and anxiety.

Science.gov (United States)

Mennella, Rocco; Patron, Elisabetta; Palomba, Daniela

2017-05-01

Frontal alpha asymmetry has been proposed to underlie the balance between approach and withdrawal motivation associated to each individual's affective style. Neurofeedback of EEG frontal alpha asymmetry represents a promising tool to reduce negative affect, although its specific effects on left/right frontal activity and approach/withdrawal motivation are still unclear. The present study employed a neurofeedback training to increase frontal alpha asymmetry (right - left), in order to evaluate discrete changes in alpha power at left and right sites, as well as in positive and negative affect, anxiety and depression. Thirty-two right-handed females were randomly assigned to receive either the neurofeedback on frontal alpha asymmetry, or an active control training (N = 16 in each group). The asymmetry group showed an increase in alpha asymmetry driven by higher alpha at the right site (p neurofeedback for the reduction of negative affect and anxiety in clinical settings. Copyright © 2017 Elsevier Ltd. All rights reserved.

Frontal EEG Asymmetry of Mood: A Mini-Review

Directory of Open Access Journals (Sweden)

Massimiliano Palmiero

2017-11-01

Full Text Available The present mini-review was aimed at exploring the frontal EEG asymmetry of mood. With respect to emotion, interpreted as a discrete affective process, mood is more controllable, more nebulous, and more related to mind/cognition; in addition, causes are less well-defined than those eliciting emotion. Therefore, firstly, the rational for the distinction between emotion and mood was provided. Then, the main frontal EEG asymmetry models were presented, such as the motivational approach/withdrawal, valence/arousal, capability, and inhibition asymmetric models. Afterward, the frontal EEG asymmetry of mood was investigated following three research lines, that is considering studies involving different mood induction procedures, dispositional mood (positive and negative affect, and mood alterations in both healthy and clinical populations. In general, results were found to be contradictory, no model is unequivocally supported regardless the research line considered. Different methodological issues were raised, such as: the composition of samples used across studies, in particular, gender and age were found to be critical variables that should be better addressed in future studies; the importance of third variables that might mediate the relationship between frontal EEG asymmetries and mood, for example bodily states and hormonal responses; the role of cognition, namely the interplay between mood and executive functions. In light of these issues, future research directions were proposed. Amongst others, the need to explore the neural connectivity that underpins EEG asymmetries, and the need to include both positive and negative mood conditions in the experimental designs have been highlighted.

Single-spin asymmetries in inclusive DIS and in hadronic collisions

Energy Technology Data Exchange (ETDEWEB)

Metz, Andreas; Pitonyak, Daniel [Department of Physics, Temple University, Philadelphia, PA 19122 (United States); Schaefer, Andreas; Zhou, Jian [Institute for Theoretical Physics, Regensburg University, 93053 Regensburg (Germany); Schlegel, Marc; Vogelsang, Werner [Institute for Theoretical Physics, Tuebingen University, 72076 Tuebingen (Germany)

2013-04-15

Transverse single-spin asymmetries in inclusive deep inelastic lepton-nucleon scattering can be generated through multi-photon exchange between the leptonic and the hadronic part of the process. Here we consider two-photon exchange and mainly focus on the transverse target spin asymmetry. In particular, we investigate the case where two photons couple to different quarks. Such a contribution involves a quark-photon-quark correlator in the nucleon, which has a (modeldependent) relation to the Efremov-Teryaev-Qiu-Sterman quark-gluon-quark correlator T{sub F}. Using different parameterizations for T{sub F} we compute the transverse target spin asymmetries for both a proton and a neutron target and compare the results to recent experimental data. In addition, potential implications for our general understanding of single-spin asymmetries in hard scattering processes are discussed.

Single-spin asymmetries in inclusive DIS and in hadronic collisions

International Nuclear Information System (INIS)

Metz, Andreas; Pitonyak, Daniel; Schäfer, Andreas; Zhou, Jian; Schlegel, Marc; Vogelsang, Werner

2013-01-01

Transverse single-spin asymmetries in inclusive deep inelastic lepton-nucleon scattering can be generated through multi-photon exchange between the leptonic and the hadronic part of the process. Here we consider two-photon exchange and mainly focus on the transverse target spin asymmetry. In particular, we investigate the case where two photons couple to different quarks. Such a contribution involves a quark-photon-quark correlator in the nucleon, which has a (modeldependent) relation to the Efremov-Teryaev-Qiu-Sterman quark-gluon-quark correlator T F . Using different parameterizations for T F we compute the transverse target spin asymmetries for both a proton and a neutron target and compare the results to recent experimental data. In addition, potential implications for our general understanding of single-spin asymmetries in hard scattering processes are discussed.

Superheavy thermal dark matter and primordial asymmetries

International Nuclear Information System (INIS)

Bramante, Joseph; Unwin, James

2017-01-01

The early universe could feature multiple reheating events, leading to jumps in the visible sector entropy density that dilute both particle asymmetries and the number density of frozen-out states. In fact, late time entropy jumps are usually required in models of Affleck-Dine baryogenesis, which typically produces an initial particle-antiparticle asymmetry that is much too large. An important consequence of late time dilution, is that a smaller dark matter annihilation cross section is needed to obtain the observed dark matter relic density. For cosmologies with high scale baryogenesis, followed by radiation-dominated dark matter freeze-out, we show that the perturbative unitarity mass bound on thermal relic dark matter is relaxed to 10 10 GeV. We proceed to study superheavy asymmetric dark matter models, made possible by a sizable entropy injection after dark matter freeze-out, and identify how the Affleck-Dine mechanism would generate the baryon and dark asymmetries.

Superheavy thermal dark matter and primordial asymmetries

Energy Technology Data Exchange (ETDEWEB)

Bramante, Joseph [Perimeter Institute for Theoretical Physics,31 Caroline St N, Waterloo, ON N2L 2Y5 (Canada); Unwin, James [Department of Physics, University of Illinois at Chicago,845 W Taylor St, Chicago, IL 60607 (United States)

2017-02-23

The early universe could feature multiple reheating events, leading to jumps in the visible sector entropy density that dilute both particle asymmetries and the number density of frozen-out states. In fact, late time entropy jumps are usually required in models of Affleck-Dine baryogenesis, which typically produces an initial particle-antiparticle asymmetry that is much too large. An important consequence of late time dilution, is that a smaller dark matter annihilation cross section is needed to obtain the observed dark matter relic density. For cosmologies with high scale baryogenesis, followed by radiation-dominated dark matter freeze-out, we show that the perturbative unitarity mass bound on thermal relic dark matter is relaxed to 10{sup 10} GeV. We proceed to study superheavy asymmetric dark matter models, made possible by a sizable entropy injection after dark matter freeze-out, and identify how the Affleck-Dine mechanism would generate the baryon and dark asymmetries.

Cerebral vasculitis

International Nuclear Information System (INIS)

Greenan, T.J.; Grossman, R.I.

1990-01-01

This paper reviews retrospectively MR, CT, and angiographic findings in patients with cerebral vasculitis in order to understand the strengths and weaknesses of the various imaging modalities, as well as the spectrum of imaging abnormalities in this disease entity. Studies were retrospectively reviewed in 12 patients with cerebral vasculitis proved by means of angiography and/or brain biopsy

Knowledge asymmetries about product "goodness"

DEFF Research Database (Denmark)

Kampf, Constance

and actions towards workers, and findings of independent researchers.  Currently, differing perspectives on product "goodness" are being addressed and mediated by NGOs and B-corporations, as they work with private companies and corporations to communicate product information to consumers.  One organization...... focused on scenarios where shoppers were asked about CSR in their product decisions found that: "...when consumers are given information that they trust about a company's level of social responsibility, it affects how they evaluate the company and their purchase intentions. Furthermore, a low price did.......  Asymmetries in knowledge about product "goodness" make it difficult for ethically inspired consumers to make informed decisions about the products they purchase.  These knowledge asymmetries emerge from differing perspectives on guidelines for consumer safety set by government bodies, CSR initiatives...

PERANAN KONSERVATISME PADA INFORMATION ASYMMETRY: SUATU TINJAUAN TEORETIS

Directory of Open Access Journals (Sweden)

I G.A.N. BUDIASIH

2011-07-01

Full Text Available Conservatism is one of mechanisms of corporate governance that could reduce managers’ capability to manipulate and overstate financial report, especially financial performance, so cash flow and company’s value could be increased. Conservatism is also important in decreasing agency cost and increasing the quality of financial information to increase company’s value and the share price. Financial statement employing principle of conservatism could reduce management chance to manipulate financial report and decrease deadweight loss as an agency cost emerged due to information asymmetry. Thus it can be said that conservative financial statement could reduce information asymmetry. Information asymmetry can be handled by forcing management to fully disclose the company’s condition on the financial statement. Another way is to monitor management conduct by employing independent auditor.

Transverse spin asymmetry at the A4 experiment

International Nuclear Information System (INIS)

Baunack, Sebastian

2005-01-01

The A4 collaboration at the MAMI accelerator has measured the transverse spin asymmetry in the cross section of elastic scattering of transversely polarized electrons off unpolarized protons. An azimuthal dependence of the asymmetry has been observed, the amplitudes have been determined as A bot (Q 2 =0.106 (GeV/c) 2 )=( -8.59 ±0.89 stat ±0.75 syst ).10 -6 and A bot (Q 2 =0.230 (GeV/c) 2 )=(-8.52±2.31 stat ±0.87 syst ).10 -6 . A bot arises from the imaginary part of the 2γ-exchange amplitude. Our experimentally determined values of A bot show that in the intermediate hadronic state not only the ground state of the proton, but also excited states contribute to the asymmetry. (orig.)

Thyroid Disease and Complementary and Alternative Medicine (CAM)

Science.gov (United States)

... Alternative Medicine in Thyroid Disease Complementary and Alternative Medicine in Thyroid Disease (CAM) WHAT IS COMPLEMENTARY AND ALTERNATIVE MEDICINE (CAM)? Complementary and Alternative Medicine (CAM) is defined ...

A Point-Wise Quantification of Asymmetry Using Deformation Fields

DEFF Research Database (Denmark)

Ólafsdóttir, Hildur; Lanche, Stephanie; Darvann, Tron Andre

2007-01-01

of the resulting displacement vectors on the left and right side of the symmetry plane, gives a point-wise measure of asymmetry. The asymmetry measure was applied to the study of Crouzon syndrome using Micro CT scans of genetically modified mice. Crouzon syndrome is characterised by the premature fusion of cranial...

[Cerebral protection].

Science.gov (United States)

Cattaneo, A D

1993-09-01

Cerebral protection means prevention of cerebral neuronal damage. Severe brain damage extinguishes the very "human" functions such as speech, consciousness, intellectual capacity, and emotional integrity. Many pathologic conditions may inflict injuries to the brain, therefore the protection and salvage of cerebral neuronal function must be the top priorities in the care of critically ill patients. Brain tissue has unusually high energy requirements, its stores of energy metabolites are small and, as a result, the brain is totally dependent on a continuous supply of substrates and oxygen, via the circulation. In complete global ischemia (cardiac arrest) reperfusion is characterized by an immediate reactive hyperemia followed within 20-30 min by a delayed hypoperfusion state. It has been postulated that the latter contributes to the ultimate neurologic outcome. In focal ischemia (stroke) the primary focus of necrosis is encircled by an area (ischemic penumbra) that is underperfused and contains neurotoxic substances such as free radicals, prostaglandins, calcium, and excitatory neurotransmitters. The variety of therapeutic effort that have addressed the question of protecting the brain reflects their limited success. 1) Barbiturates. After an initial enthusiastic endorsement by many clinicians and years of vigorous controversy, it can now be unequivocally stated that there is no place for barbiturate therapy following resuscitation from cardiac arrest. One presumed explanation for this negative statement is that cerebral metabolic suppression by barbiturates (and other anesthetics) is impossible in the absence of an active EEG. Conversely, in the event of incomplete ischemia EEG activity in usually present (albeit altered) and metabolic suppression and hence possibly protection can be induced with barbiturates. Indeed, most of the animal studies led to a number of recommendations for barbiturate therapy in man for incomplete ischemia. 2) Isoflurane. From a cerebral

Dynamic digitized cerebral parenchymography

International Nuclear Information System (INIS)

Theron, J.; Alachkar, F.; Nelson, M.; Mazia, D.

1992-01-01

Aortic arch injections centred on the head have been performed routinely in patients with cerebral ischaemia. Digital angiograms with modified windowing (low and narrow) have been used. This 'cerebral' arch injection allows much improved analysis of the cerebral parenchymal vascularization, giving better understanding of hemispheric ischaemia and making the decision about revascularization more rational. (orig.)

What is cerebral small vessel disease?

International Nuclear Information System (INIS)

Onodera, Osamu

2011-01-01

An accumulating amount of evidence suggests that the white matter hyperintensities on T 2 weighted brain magnetic resonance imaging predict an increased risk of dementia and gait disturbance. This state has been proposed as cerebral small vessel disease, including leukoaraiosis, Binswanger's disease, lacunar stroke and cerebral microbleeds. However, the concept of cerebral small vessel disease is still obscure. To understand the cerebral small vessel disease, the precise structure and function of cerebral small vessels must be clarified. Cerebral small vessels include several different arteries which have different anatomical structures and functions. Important functions of the cerebral small vessels are blood-brain barrier and perivasucular drainage of interstitial fluid from the brain parenchyma. Cerebral capillaries and glial endfeet, take an important role for these functions. However, the previous pathological investigations on cerebral small vessels have focused on larger arteries than capillaries. Therefore little is known about the pathology of capillaries in small vessel disease. The recent discoveries of genes which cause the cerebral small vessel disease indicate that the cerebral small vessel diseases are caused by a distinct molecular mechanism. One of the pathological findings in hereditary cerebral small vessel disease is the loss of smooth muscle cells, which is an also well-recognized finding in sporadic cerebral small vessel disease. Since pericytes have similar character with the smooth muscle cells, the pericytes should be investigated in these disorders. In addition, the loss of smooth muscle cells may result in dysfunction of drainage of interstitial fluid from capillaries. The precise correlation between the loss of smooth muscle cells and white matter disease is still unknown. However, the function that is specific to cerebral small vessel may be associated with the pathogenesis of cerebral small vessel disease. (author)

Symmetry, asymmetry and dissymmetry

International Nuclear Information System (INIS)

Wackenheim, A.; Zollner, G.

1987-01-01

The authors discuss the concept of symmetry and defect of symmetry in radiological imaging and recall the definition of asymmetry (congenital or constitutional) and dissymmetry (acquired). They then describe a rule designed for the cognitive method of automatic evaluation of shape recognition data and propose the use of reversal symmetry [fr

Functional correlates of positional and gender-specific renal asymmetry in Drosophila.

Directory of Open Access Journals (Sweden)

Venkateswara R Chintapalli

Full Text Available In humans and other animals, the internal organs are positioned asymmetrically in the body cavity, and disruption of this body plan can be fatal in humans. The mechanisms by which internal asymmetry are established are presently the subject of intense study; however, the functional significance of internal asymmetry (outside the brain is largely unexplored. Is internal asymmetry functionally significant, or merely an expedient way of packing organs into a cavity?Like humans, Drosophila shows internal asymmetry, with the gut thrown into stereotyped folds. There is also renal asymmetry, with the rightmost pair of renal (Malpighian tubules always ramifying anteriorly, and the leftmost pair always sitting posteriorly in the body cavity. Accordingly, transcriptomes of anterior-directed (right-side and posterior-directed (left-side Malpighian (renal tubules were compared in both adult male and female Drosophila. Although genes encoding the basic functions of the tubules (transport, signalling were uniformly expressed, some functions (like innate immunity showed positional or gender differences in emphasis; others, like calcium handling or the generation of potentially toxic ammonia, were reserved for just the right-side or left-side tubules, respectively. These findings correlated with the distinct locations of each tubule pair within the body cavity. Well known developmental genes (like dorsocross, dachshund and doublesex showed continuing, patterned expression in adult tubules, implying that somatic tissues maintain both left-right and gender identities throughout life. Gender asymmetry was also noted, both in defence and in male-specific expression of receptors for neuropeptide F and sex-peptide: NPF elevated calcium only in male tubules.Accordingly, the physical asymmetry of the tubules in the body cavity is directly adaptive. Now that the detailed machinery underlying internal asymmetry is starting to be delineated, our work invites the

Voxel-wise grey matter asymmetry analysis in left- and right-handers.

Science.gov (United States)

Ocklenburg, Sebastian; Friedrich, Patrick; Güntürkün, Onur; Genç, Erhan

2016-10-28

Handedness is thought to originate in the brain, but identifying its structural correlates in the cortex has yielded surprisingly incoherent results. One idea proclaimed by several authors is that structural grey matter asymmetries might underlie handedness. While some authors have found significant associations with handedness in different brain areas (e.g. in the central sulcus and precentral sulcus), others have failed to identify such associations. One method used by many researchers to determine structural grey matter asymmetries is voxel based morphometry (VBM). However, it has recently been suggested that the standard VBM protocol might not be ideal to assess structural grey matter asymmetries, as it establishes accurate voxel-wise correspondence across individuals but not across both hemispheres. This could potentially lead to biased and incoherent results. Recently, a new toolbox specifically geared at assessing structural asymmetries and involving accurate voxel-wise correspondence across hemispheres has been published [F. Kurth, C. Gaser, E. Luders. A 12-step user guide for analyzing voxel-wise gray matter asymmetries in statistical parametric mapping (SPM), Nat Protoc 10 (2015), 293-304]. Here, we used this new toolbox to re-assess grey matter asymmetry differences in left- vs. right-handers and linked them to quantitative measures of hand preference and hand skill. While we identified several significant left-right asymmetries in the overall sample, no difference between left- and right-handers reached significance after correction for multiple comparisons. These findings indicate that the structural brain correlates of handedness are unlikely to be rooted in macroscopic grey matter area differences that can be assessed with VBM. Future studies should focus on other potential structural correlates of handedness, e.g. structural white matter asymmetries. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Analysis of skull asymmetry in different historical periods using radiological examinations

International Nuclear Information System (INIS)

Gawlikowska, A.; Czerwinski, F.; Dzieciolowska, E.; Miklaszewska, D.; Adamiec, E.; Szczurowski, J.

2007-01-01

Asymmetry is a very common phenomenon in nature. Occurrence of asymmetry and knowledge of correct structure, especially a range of variability which is not a pathology but only an individual variation, are the basis for interpretation of results of radiological examination of the skulls both in research work and in diagnostic examinations, which are widely performed in modern medicine. There are many methods of estimation of the asymmetry. The aim of this study was to estimate the symmetry of skulls from selected historic populations. The studied material consisted of two skull populations - contemporary consisting of 82 skulls and medieval - 77 skulls from Grodek. X-rays in P-A and skull-base projections were performed. The images were scanned and calibrated by means of MicroStation 95 Academic Edition software. Using tools for measurement of vector elements, distances between selected bilateral points of the skull were taken. All data were analyzed statistically. Asymmetry was observed in the skulls of both populations. Some diameters were higher on the left side, some on the right side. High levels of asymmetry index in the superior facial part and in the posterior part of the skull base were observed. The levels of the asymmetry indexes in both groups were similar. Radiological pictures in two projections should be taken for correct analysis of the skull asymmetry. The examination of the asymmetry of the landmarks should be based on the analysis of diameters from two different points of reference. The human skull does not demonstrate a clear domination of one side. The largest variations were observed in the shape and localization of the foramina of the skull . It is associated with the differences of the position of the neurovascular elements which pass through these foramina. (author)

The application of microfocal radiography to neuroanatomy and neuropathology research, and its relation to cerebral magnification angiography and brain scan interpretation. Chapter 3

International Nuclear Information System (INIS)

Saunders, R.L. de C.H.

1980-01-01

Microfocal radiography is used to study post mortem, the microcirculatory and neuronal organization of the normal and diseased brain, as well as to interpret the images obtained clinically by the new techniques of cerebral magnification angiography and X-ray brain scanning. An outline of the basic technique underlying CT scanning and magnification radiography of the living human brain is given to facilitate the understanding of why microfocal radiography is central to magnification radiography and complementary to CT scanning. Microangiography, one of the microfocal radiographic techniques, is discussed at length in relation to the microvasculature of the human cerebral cortex, the vasculature of the subcortical or medullary white matter, the microvascular patterns of the central grey matter and internal capsule, the vascular patterns of the visual cortex and hippocampus; the application of microangiography to the spinal cord and nerve roots is also discussed. Another microfocal radiographic technique described is cerebral historadiography, i.e. X-ray studies of brain histology, with particular reference to the human hippocampal formation. Finally, the correlation of microfocal X-ray and brain CT scan images is discussed. (U.K.)

Hemispheric asymmetry and theory of mind: is there an association?

Science.gov (United States)

Herzig, Daniela A; Sullivan, Sarah; Evans, Jonathan; Corcoran, Rhiannon; Mohr, Christine

2012-01-01

In autism and schizophrenia attenuated/atypical functional hemispheric asymmetry and theory of mind impairments have been reported, suggesting common underlying neuroscientific correlates. We here investigated whether impaired theory of mind performance is associated with attenuated/atypical hemispheric asymmetry. An association may explain the co-occurrence of both dysfunctions in psychiatric populations. Healthy participants (n=129) performed a left hemisphere (lateralised lexical decision task) and right hemisphere (lateralised face decision task) dominant task as well as a visual cartoon task to assess theory of mind performance. Linear regression analyses revealed inconsistent associations between theory of mind performance and functional hemisphere asymmetry: enhanced theory of mind performance was only associated with (1) faster right hemisphere language processing, and (2) reduced right hemisphere dominance for face processing (men only). The majority of non-significant findings suggest that theory of mind and functional hemispheric asymmetry are unrelated. Instead of "overinterpreting" the two significant results, discrepancies in the previous literature relating to the problem of the theory of mind concept, the variety of tasks, and the lack of normative data are discussed. We also suggest how future studies could explore a possible link between hemispheric asymmetry and theory of mind.

SIMULATION STUDY OF HEMISPHERIC PHASE-ASYMMETRY IN THE SOLAR CYCLE

Energy Technology Data Exchange (ETDEWEB)

Shukuya, D.; Kusano, K., E-mail: kusano@nagoya-u.jp [Institute for Space-Earth Environmental Research, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 4648601 (Japan)

2017-01-20

Observations of the Sun suggest that solar activities systematically create north–south hemispheric asymmetries. For instance, the hemisphere in which sunspot activity is more active tends to switch after the early half of each solar cycle. Svalgaard and Kamide recently pointed out that the time gaps of polar field reversal between the northern and southern hemispheres are simply consequences of the asymmetry of sunspot activity. However, the mechanism underlying the asymmetric feature in solar cycle activity is not yet well understood. In this paper, in order to explain the cause of the asymmetry from the theoretical point of view, we investigate the relationship between the dipole- and quadrupole-type components of the magnetic field in the solar cycle using the mean-field theory based on the flux transport dynamo model. As a result, we found that there are two different attractors of the solar cycle, in which either the north or the south polar field is first reversed, and that the flux transport dynamo model explains well the phase-asymmetry of sunspot activity and the polar field reversal without any ad hoc source of asymmetry.

Collins Fragmentation and the Single Transverse Spin Asymmetry

OpenAIRE

Yuan, Feng; Zhou, Jian

2009-01-01

We study the Collins mechanism for the single transverse spin asymmetry in the collinear factorization approach. The correspondent twist-three fragmentation function is identified. We show that the Collins function calculated in this approach is universal. We further examine its contribution to the single transverse spin asymmetry of semi-inclusive hadron production in deep inelastic scattering and demonstrate that the transverse momentum dependent and twist-three collinear approaches are con...

Collins and Sivers asymmetries for pions and kaons in muon-deuteron DIS

Czech Academy of Sciences Publication Activity Database

Alekseev, M.; Alexakhin, V. Yu.; Alexandrov, Yu.; Alexeev, G. D.; Amoroso, A.; Arbuzov, A.; Badelek, B.; Balestra, F.; Ball, J.; Barth, J.; Baum, G.; Bedfer, Y.; Bernet, C.; Bertini, R.; Bettinelli, M.; Birsa, R.; Bisplinghoff, J.; Bordalo, P.; Bradamante, F.; Bravar, A.; Bressan, A.; Brona, G.; Burtin, E.; Bussa, M.; Chapiro, A.; Chiosso, M.; Cicuttin, A.; Colantoni, M.; Costa, S.; Crespo, M.; Dalla Torre, S.; Dafni, T.; Das, S.; Dasgupta, S. S.; De Masi, R.; Dedek, N.; Denisov, O.; Dhara, L.; Diaz, V.; Dinkelbach, A.; Donskov, S.; Dorofeev, V.; Doshita, N.; Duic, V.; Dünnweber, W.; Efremov, A.V.; Eversheim, P.; Eyrich, W.; Faessler, M.; Falaleev, V.; Ferrero, A.; Ferrero, L.; Finger, M.; Finger jr., M.; Fischer, H.; Franco, C.; Franz, J.; Friedrich, J.; Frolov, V.; Garfagnini, R.; Gautheron, F.; Gavrichtchouk, O.; Gazda, R.; Gerassimov, S.; Geyer, R.; Giorgi, M.; Gobbo, B.; Goertz, S.; Gorin, A.; Grabmüller, S.; Grajek, O.; Grasso, A.; Grube, B.; Gushterski, R.; Guskov, A.; Haas, F.; Hannappel, J.; von Harrach, D.; Hasegawa, T.; Heckmann, J.; Hedicke, S.; Heinsius, F.; Hermann, R.; Hess, C.; Hinterberger, F.; von Hodenberg, M.; Horikawa, N.; Horikawa, S.; d'Hose, N.; Ilgner, C.; Ioukaev, A.; Ishimoto, S.; Ivanov, O.; Ivanshin, Yu.; Iwata, T.; Jahn, R.; Janata, A.; Jasinski, P.; Joosten, R.; Jouravlev, N. I.; Kabuss, E.; Kang, D.; Ketzer, B.; Khaustov, G.; Khokhlov, Y.; Kisselev, Y.; Klein, F.; Klimaszewski, K.; Koblitz, S.; Koivuniemi, J.; Kolosov, V.; Komissarov, E.; Kondo, K.; Königsmann, K.; Konorov, I.; Konstantinov, V.; Korentchenko, A.; Korzenev, A.; Kotzinian, A.; Koutchinski, N.; Kouznetsov, O.; Kral, A.; Kravchuk, N.; Kroumchtein, Z.; Kuhn, R.; Kunne, F.; Kurek, K.; Ladygin, M.; Lamanna, M.; Le Goff, J.; Lednev, A.; Lehmann, A.; Levorato, S.; Lichtenstadt, J.; Liska, T.; Ludwig, I.; Maggiora, A.; Maggiora, M.; Magnon, A.; Mallot, G.; Mann, A.; Marchand, C.; Marroncle, J.; Martin, A.; Marzec, J.; Massmann, F.; Matsuda, T.; Maximov, A.; Meyer, W.; Mielech, A.; Mikhailov, Y.; Moinester, M.; Mutter, A.; Nagaytsev, A.; Nagel, T.; Nähle, O.; Nassalski, J.; Neliba, S.; Nerling, F.; Neubert, S.; Neyret, D.; Nikolaenko, V.; Nikolaev, K.; Olshevsky, A.; Ostrick, M.; Padee, A.; Pagano, P.; Panebianco, S.; Panknin, R.; Panzieri, D.; Paul, S.; Pawlukiewicz-Kaminska, B.; Pesaro, G.; Peshekhonov, D.; Peshekhonov, V.; Piragino, G.; Platchkov, S.; Pochodzalla, J.; Polak, J.; Polyakov, V.; Pretz, J.; Procureur, S.; Quintans, C.; Rajotte, J.; Ramos, S.; Rapatsky, V.; Reicherz, G.; Reggiani, D.; Richter, A.; Robinet, F.; Rocco, E.; Rondio, E.; Rozhdestvensky, A.; Ryabchikov, D.; Samoylenko, V.; Sandacz, A.; Santos, H.; Sapozhnikov, M.; Sarkar, S.; Savin, I.; Sbrizzai, G.; Schiavon, P.; Schill, C.; Schmitt, L.; Schönmeier, P.; Schröder, W.; Shevchenko, O.; Siebert, H.; Silva, L.; Sinha, L.; Sissakian, A.; Slunecka, M.; Smirnov, G.; Sosio, S.; Sozzi, F.; Srnka, Aleš; Stinzing, F.; Stolarski, M.; Sugonyaev, V.; Sulc, M.; Sulej, R.; Tchalishev, V.; Tessaro, S.; Tessarotto, F.; Teufel, A.; Tkatchev, L.; Venugopal, G.; Virius, M.; Vlassov, N.; Vossen, A.; Webb, R.; Weise, E.; Weitzel, Q.; Windmolders, R.; Wirth, S.; Wislicki, W.; Wollny, H.; Zaremba, K.; Zavertyaev, M.; Zemlyanichkina, E.; Zhao, J.; Ziegler, R.; Zvyagin, A.

2009-01-01

Roč. 673, č. 2 (2009), s. 127-135 ISSN 0370-2693 R&D Projects: GA MŠk ME 492 Institutional research plan: CEZ:AV0Z20650511 Keywords : deuteron * transverse single-spin asymmetry * identified hadrons * Collins asymmetry * Sivers asymmetry Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 5.083, year: 2009

Cerebral malaria: susceptibility weighted MRI

Directory of Open Access Journals (Sweden)

Vinit Baliyan

2015-03-01

Full Text Available Cerebral malaria is one of the fatal complications of Plasmodium falciparum infection. Pathogenesis involves cerebral microangiopathy related to microvascular plugging by infected red blood cells. Conventional imaging with MRI and CT do not reveal anything specific in case of cerebral malaria. Susceptibility weighted imaging, a recent advance in the MRI, is very sensitive to microbleeds related to microangiopathy. Histopathological studies in cerebral malaria have revealed microbleeds in brain parenchyma secondary to microangiopathy. Susceptibility weighted imaging, being exquisitely sensitive to microbleeds may provide additional information and improve the diagnostic accuracy of MRI in cerebral malaria.

Yield asymmetry design of magnesium alloys by integrated computational materials engineering

Energy Technology Data Exchange (ETDEWEB)

Li, Dongsheng [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Joshi, Vineet [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lavender, Curt [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Khaleel, Mohammad [Qatar Foundation Research adn Development (Qatar); Ahzi, Said [Univ. of Strasbourg (France)

2013-11-01

Deformation asymmetry of magnesium alloys is an important factor on machine design in the automobile industry. Represented by the ratio of compressive yield stress (CYS) against tensile yield stress (TYS), deformation asymmetry is strongly related to texture and grain size. A polycrystalline viscoplasticity model, modified intermediate Φ-model, is used to predict the deformation behavior of magnesium alloys with different grain sizes. Validated with experimental results, integrated computational materials engineering is applied to find out the route in achieving desired asymmetry via thermomechanical processing. For example, CYS/TYS in rolled texture is smaller than 1 under different loading directions. In other textures, such as extruded texture, CYS/TYS is large along the normal direction. Starting from rolled texture, asymmetry will increase to close to 1 along the rolling direction after being compressed to a strain of 0.2. Our modified Φ-model also shows that grain refinement increases CYS/TYS. Along with texture control, grain refinement also can optimize the yield asymmetry. After the grain size decreases to a critical value, CYS/TYS reaches to 1 because CYS increases much faster than TYS. By tailoring the microstructure using texture control and grain refinement, it is achievable to optimize yield asymmetry in wrought magnesium alloys.

Combined Forward-Backward Asymmetry Measurements in Top-Antitop Quark Production at the Tevatron.

Science.gov (United States)

Aaltonen, T; Abazov, V M; Abbott, B; Acharya, B S; Adams, M; Adams, T; Agnew, J P; Alexeev, G D; Alkhazov, G; Alton, A; Amerio, S; Amidei, D; Anastassov, A; Annovi, A; Antos, J; Apollinari, G; Appel, J A; Arisawa, T; Artikov, A; Asaadi, J; Ashmanskas, W; Askew, A; Atkins, S; Auerbach, B; Augsten, K; Aurisano, A; Aushev, V; Aushev, Y; Avila, C; Azfar, F; Badaud, F; Badgett, W; Bae, T; Bagby, L; Baldin, B; Bandurin, D V; Banerjee, S; Barbaro-Galtieri, A; Barberis, E; Baringer, P; Barnes, V E; Barnett, B A; Barria, P; Bartlett, J F; Bartos, P; Bassler, U; Bauce, M; Bazterra, V; Bean, A; Bedeschi, F; Begalli, M; Behari, S; Bellantoni, L; Bellettini, G; Bellinger, J; Benjamin, D; Beretvas, A; Beri, S B; Bernardi, G; Bernhard, R; Bertram, I; Besançon, M; Beuselinck, R; Bhat, P C; Bhatia, S; Bhatnagar, V; Bhatti, A; Bland, K R; Blazey, G; Blessing, S; Bloom, K; Blumenfeld, B; Bocci, A; Bodek, A; Boehnlein, A; Boline, D; Boos, E E; Borissov, G; Bortoletto, D; Borysova, M; Boudreau, J; Boveia, A; Brandt, A; Brandt, O; Brigliadori, L; Brochmann, M; Brock, R; Bromberg, C; Bross, A; Brown, D; Brucken, E; Bu, X B; Budagov, J; Budd, H S; Buehler, M; Buescher, V; Bunichev, V; Burdin, S; Burkett, K; Busetto, G; Bussey, P; Buszello, C P; Butti, P; Buzatu, A; Calamba, A; Camacho-Pérez, E; Camarda, S; Campanelli, M; Canelli, F; Carls, B; Carlsmith, D; Carosi, R; Carrillo, S; Casal, B; Casarsa, M; Casey, B C K; Castilla-Valdez, H; Castro, A; Catastini, P; Caughron, S; Cauz, D; Cavaliere, V; Cerri, A; Cerrito, L; Chakrabarti, S; Chan, K M; Chandra, A; Chapelain, A; Chapon, E; Chen, G; Chen, Y C; Chertok, M; Chiarelli, G; Chlachidze, G; Cho, K; Cho, S W; Choi, S; Chokheli, D; Choudhary, B; Cihangir, S; Claes, D; Clark, A; Clarke, C; Clutter, J; Convery, M E; Conway, J; Cooke, M; Cooper, W E; Corbo, M; Corcoran, M; Cordelli, M; Couderc, F; Cousinou, M-C; Cox, C A; Cox, D J; Cremonesi, M; Cruz, D; Cuevas, J; Culbertson, R; Cuth, J; Cutts, D; Das, A; d'Ascenzo, N; Datta, M; Davies, G; de Barbaro, P; de Jong, S J; De La Cruz-Burelo, E; Déliot, F; Demina, R; Demortier, L; Deninno, M; Denisov, D; Denisov, S P; D'Errico, M; Desai, S; Deterre, C; DeVaughan, K; Devoto, F; Di Canto, A; Di Ruzza, B; Diehl, H T; Diesburg, M; Ding, P F; Dittmann, J R; Dominguez, A; Donati, S; D'Onofrio, M; Dorigo, M; Driutti, A; Drutskoy, A; Dubey, A; Dudko, L V; Duperrin, A; Dutt, S; Eads, M; Ebina, K; Edgar, R; Edmunds, D; Elagin, A; Ellison, J; Elvira, V D; Enari, Y; Erbacher, R; Errede, S; Esham, B; Evans, H; Evdokimov, A; Evdokimov, V N; Farrington, S; Fauré, A; Feng, L; Ferbel, T; Fernández Ramos, J P; Fiedler, F; Field, R; Filthaut, F; Fisher, W; Fisk, H E; Flanagan, G; Forrest, R; Fortner, M; Fox, H; Franc, J; Franklin, M; Freeman, J C; Frisch, H; Fuess, S; Funakoshi, Y; Galloni, C; Garbincius, P H; Garcia-Bellido, A; García-González, J A; Garfinkel, A F; Garosi, P; Gavrilov, V; Geng, W; Gerber, C E; Gerberich, H; Gerchtein, E; Gershtein, Y; Giagu, S; Giakoumopoulou, V; Gibson, K; Ginsburg, C M; Ginther, G; Giokaris, N; Giromini, P; Glagolev, V; Glenzinski, D; Gogota, O; Gold, M; Goldin, D; Golossanov, A; Golovanov, G; Gomez, G; Gomez-Ceballos, G; Goncharov, M; González López, O; Gorelov, I; Goshaw, A T; Goulianos, K; Gramellini, E; Grannis, P D; Greder, S; Greenlee, H; Grenier, G; Gris, Ph; Grivaz, J-F; Grohsjean, A; Grosso-Pilcher, C; Grünendahl, S; Grünewald, M W; Guillemin, T; Guimaraes da Costa, J; Gutierrez, G; Gutierrez, P; Hahn, S R; Haley, J; Han, J Y; Han, L; Happacher, F; Hara, K; Harder, K; Hare, M; Harel, A; Harr, R F; Harrington-Taber, T; Hatakeyama, K; Hauptman, J M; Hays, C; Hays, J; Head, T; Hebbeker, T; Hedin, D; Hegab, H; Heinrich, J; Heinson, A P; Heintz, U; Hensel, C; Heredia-De La Cruz, I; Herndon, M; Herner, K; Hesketh, G; Hildreth, M D; Hirosky, R; Hoang, T; Hobbs, J D; Hocker, A; Hoeneisen, B; Hogan, J; Hohlfeld, M; Holzbauer, J L; Hong, Z; Hopkins, W; Hou, S; Howley, I; Hubacek, Z; Hughes, R E; Husemann, U; Hussein, M; Huston, J; Hynek, V; Iashvili, I; Ilchenko, Y; Illingworth, R; Introzzi, G; Iori, M; Ito, A S; Ivanov, A; Jabeen, S; Jaffré, M; James, E; Jang, D; Jayasinghe, A; Jayatilaka, B; Jeon, E J; Jeong, M S; Jesik, R; Jiang, P; Jindariani, S; Johns, K; Johnson, E; Johnson, M; Jonckheere, A; Jones, M; Jonsson, P; Joo, K K; Joshi, J; Jun, S Y; Jung, A W; Junk, T R; Juste, A; Kajfasz, E; Kambeitz, M; Kamon, T; Karchin, P E; Karmanov, D; Kasmi, A; Kato, Y; Katsanos, I; Kaur, M; Kehoe, R; Kermiche, S; Ketchum, W; Keung, J; Khalatyan, N; Khanov, A; Kharchilava, A; Kharzheev, Y N; Kilminster, B; Kim, D H; Kim, H S; Kim, J E; Kim, M J; Kim, S H; Kim, S B; Kim, Y J; Kim, Y K; Kimura, N; Kirby, M; Kiselevich, I; Kohli, J M; Kondo, K; Kong, D J; Konigsberg, J; Kotwal, A V; Kozelov, A V; Kraus, J; Kreps, M; Kroll, J; Kruse, M; Kuhr, T; Kumar, A; Kupco, A; Kurata, M; Kurča, T; Kuzmin, V A; Laasanen, A T; Lammel, S; Lammers, S; Lancaster, M; Lannon, K; Latino, G; Lebrun, P; Lee, H S; Lee, H S; Lee, J S; Lee, S W; Lee, W M; Lei, X; Lellouch, J; Leo, S; Leone, S; Lewis, J D; Li, D; Li, H; Li, L; Li, Q Z; Lim, J K; Limosani, A; Lincoln, D; Linnemann, J; Lipaev, V V; Lipeles, E; Lipton, R; Lister, A; Liu, H; Liu, Q; Liu, T; Liu, Y; Lobodenko, A; Lockwitz, S; Loginov, A; Lokajicek, M; Lopes de Sa, R; Lucchesi, D; Lucà, A; Lueck, J; Lujan, P; Lukens, P; Luna-Garcia, R; Lungu, G; Lyon, A L; Lys, J; Lysak, R; Maciel, A K A; Madar, R; Madrak, R; Maestro, P; Magaña-Villalba, R; Malik, S; Malik, S; Malyshev, V L; Manca, G; Manousakis-Katsikakis, A; Mansour, J; Marchese, L; Margaroli, F; Marino, P; Martínez-Ortega, J; Matera, K; Mattson, M E; Mazzacane, A; Mazzanti, P; McCarthy, R; McGivern, C L; McNulty, R; Mehta, A; Mehtala, P; Meijer, M M; Melnitchouk, A; Menezes, D; Mercadante, P G; Merkin, M; Mesropian, C; Meyer, A; Meyer, J; Miao, T; Miconi, F; Mietlicki, D; Mitra, A; Miyake, H; Moed, S; Moggi, N; Mondal, N K; Moon, C S; Moore, R; Morello, M J; Mukherjee, A; Mulhearn, M; Muller, Th; Murat, P; Mussini, M; Nachtman, J; Nagai, Y; Naganoma, J; Nagy, E; Nakano, I; Napier, A; Narain, M; Nayyar, R; Neal, H A; Negret, J P; Nett, J; Neustroev, P; Nguyen, H T; Nigmanov, T; Nodulman, L; Noh, S Y; Norniella, O; Nunnemann, T; Oakes, L; Oh, S H; Oh, Y D; Okusawa, T; Orava, R; Orduna, J; Ortolan, L; Osman, N; Pagliarone, C; Pal, A; Palencia, E; Palni, P; Papadimitriou, V; Parashar, N; Parihar, V; Park, S K; Parker, W; Partridge, R; Parua, N; Patwa, A; Pauletta, G; Paulini, M; Paus, C; Penning, B; Perfilov, M; Peters, Y; Petridis, K; Petrillo, G; Pétroff, P; Phillips, T J; Piacentino, G; Pianori, E; Pilot, J; Pitts, K; Plager, C; Pleier, M-A; Podstavkov, V M; Pondrom, L; Popov, A V; Poprocki, S; Potamianos, K; Pranko, A; Prewitt, M; Price, D; Prokopenko, N; Prokoshin, F; Ptohos, F; Punzi, G; Qian, J; Quadt, A; Quinn, B; Ratoff, P N; Razumov, I; Redondo Fernández, I; Renton, P; Rescigno, M; Rimondi, F; Ripp-Baudot, I; Ristori, L; Rizatdinova, F; Robson, A; Rodriguez, T; Rolli, S; Rominsky, M; Ronzani, M; Roser, R; Rosner, J L; Ross, A; Royon, C; Rubinov, P; Ruchti, R; Ruffini, F; Ruiz, A; Russ, J; Rusu, V; Sajot, G; Sakumoto, W K; Sakurai, Y; Sánchez-Hernández, A; Sanders, M P; Santi, L; Santos, A S; Sato, K; Savage, G; Saveliev, V; Savitskyi, M; Savoy-Navarro, A; Sawyer, L; Scanlon, T; Schamberger, R D; Scheglov, Y; Schellman, H; Schlabach, P; Schmidt, E E; Schott, M; Schwanenberger, C; Schwarz, T; Schwienhorst, R; Scodellaro, L; Scuri, F; Seidel, S; Seiya, Y; Sekaric, J; Semenov, A; Severini, H; Sforza, F; Shabalina, E; Shalhout, S Z; Shary, V; Shaw, S; Shchukin, A A; Shears, T; Shepard, P F; Shimojima, M; Shkola, O; Shochet, M; Shreyber-Tecker, I; Simak, V; Simonenko, A; Skubic, P; Slattery, P; Sliwa, K; Smith, J R; Snider, F D; Snow, G R; Snow, J; Snyder, S; Söldner-Rembold, S; Song, H; Sonnenschein, L; Sorin, V; Soustruznik, K; St Denis, R; Stancari, M; Stark, J; Stefaniuk, N; Stentz, D; Stoyanova, D A; Strauss, M; Strologas, J; Sudo, Y; Sukhanov, A; Suslov, I; Suter, L; Svoisky, P; Takemasa, K; Takeuchi, Y; Tang, J; Tecchio, M; Teng, P K; Thom, J; Thomson, E; Thukral, V; Titov, M; Toback, D; Tokar, S; Tokmenin, V V; Tollefson, K; Tomura, T; Tonelli, D; Torre, S; Torretta, D; Totaro, P; Trovato, M; Tsai, Y-T; Tsybychev, D; Tuchming, B; Tully, C; Ukegawa, F; Uozumi, S; Uvarov, L; Uvarov, S; Uzunyan, S; Van Kooten, R; van Leeuwen, W M; Varelas, N; Varnes, E W; Vasilyev, I A; Vázquez, F; Velev, G; Vellidis, C; Verkheev, A Y; Vernieri, C; Vertogradov, L S; Verzocchi, M; Vesterinen, M; Vidal, M; Vilanova, D; Vilar, R; Vizán, J; Vogel, M; Vokac, P; Volpi, G; Wagner, P; Wahl, H D; Wallny, R; Wang, M H L S; Wang, S M; Warchol, J; Waters, D; Watts, G; Wayne, M; Weichert, J; Welty-Rieger, L; Wester, W C; Whiteson, D; Wicklund, A B; Wilbur, S; Williams, H H; Williams, M R J; Wilson, G W; Wilson, J S; Wilson, P; Winer, B L; Wittich, P; Wobisch, M; Wolbers, S; Wolfmeister, H; Wood, D R; Wright, T; Wu, X; Wu, Z; Wyatt, T R; Xie, Y; Yamada, R; Yamamoto, K; Yamato, D; Yang, S; Yang, T; Yang, U K; Yang, Y C; Yao, W-M; Yasuda, T; Yatsunenko, Y A; Ye, W; Ye, Z; Yeh, G P; Yi, K; Yin, H; Yip, K; Yoh, J; Yorita, K; Yoshida, T; Youn, S W; Yu, G B; Yu, I; Yu, J M; Zanetti, A M; Zeng, Y; Zennamo, J; Zhao, T G; Zhou, B; Zhou, C; Zhu, J; Zielinski, M; Zieminska, D; Zivkovic, L; Zucchelli, S

2018-01-26

The CDF and D0 experiments at the Fermilab Tevatron have measured the asymmetry between yields of forward- and backward-produced top and antitop quarks based on their rapidity difference and the asymmetry between their decay leptons. These measurements use the full data sets collected in proton-antiproton collisions at a center-of-mass energy of sqrt[s]=1.96  TeV. We report the results of combinations of the inclusive asymmetries and their differential dependencies on relevant kinematic quantities. The combined inclusive asymmetry is A_{FB}^{tt[over ¯]}=0.128±0.025. The combined inclusive and differential asymmetries are consistent with recent standard model predictions.

Do gasoline prices exhibit asymmetry? Not usually

International Nuclear Information System (INIS)

Douglas, Christopher C.

2010-01-01

Previous studies have found evidence of asymmetric price adjustment in U.S. retail gasoline prices in that gasoline prices rise more rapidly in response to a cost increase than fall in response to a cost decrease. By estimating a threshold cointegration model that allows for multiple regimes, I am able to test how sensitive this result is to outlying observations. In contrast to previous studies, I find little evidence of asymmetry for the vast majority of observations and that the asymmetry is being driven by a small number of outlying observations. (author)

Cerebral Oximetry in Cardiac Surgery

Directory of Open Access Journals (Sweden)

A. N. Shepelyuk

2012-01-01

Full Text Available Based on the data of numerous current references, the review describes different neuromonitoring methods during cardiac surgery under extracorporeal circulation. It shows that it is important and necessary to make neuromonitoring for the early diagnosis and prevention of neurological complications after cardiac surgery. Particular attention is given to cerebral oximetry; the possibilities and advantages of this technique are described. Correction of cerebral oximetric values is shown to improve survival rates and to reduce the incidence of postoperative complications. Lack of cerebral oximetry monitoring denudes a clinician of important information and possibilities to optimize patient status and to prevent potentially menacing complications, which allows one to conclude that it is necessary to use cerebral oximetry procedures within neu-romonitoring in cardiac surgery. Key words: extracorporeal circulation, cerebral oximetry, neurological dysfunction, cerebral oxygenation.

Nonlinear growth dynamics and the origin of fluctuating asymmetry

Science.gov (United States)

Emlen, J.M.; Freeman, D.C.; Graham, J.H.

1993-01-01

The nonlinear, complex nature of biosynthesis magnifies the impacts of small, random perturbations on organism growth, leading to distortions in adaptive allometries and, in particular, to fluctuating asymmetry. These distortions can be partly checked by cell-cell and inter-body part feedback during growth and development, though the latter mechanism also may lead to complex patterns in right-left asymmetry. Stress can be expected to increase the degree to which random growth perturbations are magnified and may also result in disruption of the check mechanisms, thus exaggerating fluctuating asymmetry.The processes described not only provide one explanation for the existence of fluctuating asymmetry and its augmentation under stress, but suggest additional effects of stress as well. Specifically, stress is predicted to lead to decreased fractal dimension of bone sutures and branching structures in animals, and in increased dimension of growth trace patterns such as those found in mollusc shells and fish otoliths and scales.A basic yet broad primer on fractals and chaos is provided as background for the theoretical development in this manuscript.

Cerebral venous angioma

International Nuclear Information System (INIS)

Inagawa, Tetsuji; Taguchi, Haruyoshi; Kamiya, Kazuko; Yano, Takashi; Nakajima, Reiko

1984-01-01

This report presents a 27-year-old male patient who was diagnosed as having cerebral venous angioma in the postero-temporal area by CT scan and cerebral angiography. The patient improved by removing angioma with electrocoagulation of medullary veins. (Namekawa, K.)

Investors’ risk attitudes and stock price fluctuation asymmetry

Science.gov (United States)

Zhang, Yu; Li, Honggang

2011-05-01

Price rise/fall asymmetry, which indicates enduring but modest rises and sudden short-term falls, is a ubiquitous phenomenon in stock markets throughout the world. Instead of the widely used time series method, we adopt inverse statistics from turbulence to analyze this asymmetry. To explore its underlying mechanism, we build a multi-agent model with two kinds of investors, which are specifically referred to as fundamentalists and chartists. Inspired by Kahneman and Tversky’s claim regarding peoples’ asymmetric psychological responses to the equivalent levels of gains and losses, we assume that investors take different risk attitudes to gains and losses and adopt different trading strategies. The simulation results of the model developed herein are consistent with empirical work, which may support our conjecture that investors’ asymmetric risk attitudes might be one origin of rise/fall asymmetry.

Measuring the cosmological lepton asymmetry through the CMB anisotropy

CERN Document Server

Kinney, W H; Kinney, William H.; Riotto, Antonio

1999-01-01

A large lepton asymmetry in the Universe is still a viable possibility and leads to many interesting phenomena such as gauge symmetry nonrestoration at high temperature. We show that a large lepton asymmetry changes the predicted cosmic microwave background (CMB) anisotropy and that any degeneracy in the relic neutrino sea will be measured to a precision of 1% or better when the CMB anisotropy is measured at the accuracy expected to result from the planned satellite missions MAP and Planck. In fact, the current measurements already put an upper limit on the lepton asymmetry of the Universe which is stronger than the one coming from considerations of primordial nucleosynthesis and structure formation.

Transverse target spin asymmetries in exclusive $\\rho^0$ muoproduction

CERN Document Server

Adolph, C; Alexakhin, V Yu; Alexandrov, Yu; Alexeev, G D; Amoroso, A; Andrieux, V; Austregesilo, A; Badelek, B; Balestra, F; Barth, J; Baum, G; Bedfer, Y; Berlin, A; Bernhard, J; Bertini, R; Bicker, K; Bieling, J; Birsa, R; Bisplinghoff, J; Boer, M; Bordalo, P; Bradamante, F; Braun, C; Bravar, A; Bressan, A; Büchele, M; Burtin, E; Capozza, L; Chiosso, M; Chung, S U; Cicuttin, A; Crespo, M L; Dalla Torre, S; Dasgupta, S S; Dasgupta, S; Denisov, O Yu; Donskov, S V; Doshita, N; Duic, V; Dünnweber, W; Dziewiecki, M; Efremov, A; Elia, C; Eversheim, P D; Eyrich, W; Faessler, M; Ferrero, A; Filin, A; Finger, M; Finger, M jr; Fischer, H; Franco, C; du Fresne von Hohenesche, N; Friedrich, J M; Frolov, V; Garfagnini, R; Gautheron, F; Gavrichtchouk, O P; Gerassimov, S; Geyer, R; Giorgi, M; Gnesi, I; Gobbo, B; Goertz, S; Grabmüller, S; Grasso, A; Grube, B; Gushterski, R; Guskov, A; Guthörl, T; Haas, F; von Harrach, D; Hahne, D; Heinsius, F H; Herrmann, F; Hess, C; Hinterberger, F; Höppner, Ch; Horikawa, N; d'Hose, N; Huber, S; Ishimoto, S; Ivanshin, Yu; Iwata, T; Jahn, R; Jary, V; Jasinski, P; Joosten, R; Kabuss, E; Kang, D; Ketzer, B; Khaustov, G V; Khokhlov, Yu A; Kisselev, Yu; Klein, F; Klimaszewski, K; Koivuniemi, J H; Kolosov, V N; Kondo, K; Königsmann, K; Konorov, I; Konstantinov, V F; Kotzinian, A M; Kouznetsov, O; Krämer, M; Kroumchtein, Z V; Kuchinski, N; Kunne, F; Kurek, K; Kurjata, R P; Lednev, A A; Lehmann, A; Levorato, S; Lichtenstadt, J; Maggiora, A; Magnon, A; Makke, N; Mallot, G K; Marchand, C; Martin, A; Marzec, J; Matousek, J; Matsuda, H; Matsuda, T; Meshcheryakov, G; Meyer, W; Michigami, T; Mikhailov, Yu V; Miyachi, Y; Morreale, A; Nagaytsev, A; Nagel, T; Nerling, F; Neubert, S; Neyret, D; Nikolaenko, V I; Novy, J; Nowak, W D; Nunes, A.S; Olshevsky, A G; Ostrick, M; Panknin, R; Panzieri, D; Parsamyan, B; Paul, S; Pesek, M; Piragino, G; Platchkov, S; Pochodzalla, J; Polak, J; Polyakov, V A; Pretz, J; Quaresma, M; Quintans, C; Ramos, S; Reicherz, G; Rocco, E; Rodionov, V; Rondio, E; Rossiyskaya, N S; Ryabchikov, D I; Samoylenko, V D; Sandacz, A; Sapozhnikov, M G; Sarkar, S; Savin, I A; Sbrizzai, G; Schiavon, P; Schill, C; Schlüter, T; Schmidt, A; Schmidt, K; Schmitt, L; Schmïden, H; Schönning, K; Schopferer, S; Schott, M; Shevchenko, O Yu; Silva, L; Sinha, L; Sirtl, S; Slunecka, M; Sosio, S; Sozzi, F; Srnka, A; Steiger, L; Stolarski, M; Sulc, M; Sulej, R; Suzuki, H; Sznajder, P; Takekawa, S; Ter Wolbeek, J; Tessaro, S; Tessarotto, F; Thibaud, F; Uhl, S; Uman, I; Vandenbroucke, M; Virius, M; Vondra, J; Wang, L; Weisrock, T; Wilfert, M; Windmolders, R; Wislicki, W; Wollny, H; Zaremba, K; Zavertyaev, M; Zemlyanichkina, E; Zhuravlev, N; Ziembicki, M

2014-01-01

Exclusive production of $\\rho^0$ mesons was studied at the COMPASS experiment by scattering 160 GeV/$c$ muons off transversely polarised protons. Five single-spin and three double-spin azimuthal asymmetries were measured as a function of $Q^2$, $x_{Bj}$, or $p_{T}^{2}$. The $\\sin \\phi_S$ asymmetry is found to be $-0.019 \\pm 0.008(stat.) \\pm 0.003(syst.)$. All other asymmetries are also found to be of small magnitude and consistent with zero within experimental uncertainties. Very recent calculations using a GPD-based model agree well with the present results. The data is interpreted as evidence for the existence of chiral-odd, transverse generalized parton distributions.

Nanomedicine in cerebral palsy

Science.gov (United States)

Balakrishnan, Bindu; Nance, Elizabeth; Johnston, Michael V; Kannan, Rangaramanujam; Kannan, Sujatha

2013-01-01

Cerebral palsy is a chronic childhood disorder that can have diverse etiologies. Injury to the developing brain that occurs either in utero or soon after birth can result in the motor, sensory, and cognitive deficits seen in cerebral palsy. Although the etiologies for cerebral palsy are variable, neuroinflammation plays a key role in the pathophysiology of the brain injury irrespective of the etiology. Currently, there is no effective cure for cerebral palsy. Nanomedicine offers a new frontier in the development of therapies for prevention and treatment of brain injury resulting in cerebral palsy. Nanomaterials such as dendrimers provide opportunities for the targeted delivery of multiple drugs that can mitigate several pathways involved in injury and can be delivered specifically to the cells that are responsible for neuroinflammation and injury. These materials also offer the opportunity to deliver agents that would promote repair and regeneration in the brain, resulting not only in attenuation of injury, but also enabling normal growth. In this review, the current advances in nanotechnology for treatment of brain injury are discussed with specific relevance to cerebral palsy. Future directions that would facilitate clinical translation in neonates and children are also addressed. PMID:24204146

[Complementary and alternative medicine in oncology].

Science.gov (United States)

Hübner, J

2013-06-01

Complementary and alternative medicine are frequently used by cancer patients. The main benefit of complementary medicine is that it gives patients the chance to become active. Complementary therapy can reduce the side effects of conventional therapy. However, we have to give due consideration to side effects and interactions: the latter being able to reduce the effectiveness of cancer therapy and so to jeopardise the success of therapy. Therefore, complementary therapy should be managed by the oncologist. It is based on a common concept of cancerogenesis with conventional therapy. Complement therapy can be assessed in studies. Alternative medicine in contrast rejects common rules of evidence-based medicine. It starts from its own concepts of cancerogenesis, which is often in line with the thinking of lay persons. Alternative medicine is offered as either "alternative" to recommended cancer treatment or is used at the same time but without due regard for the interactions. Alternative medicine is a high risk to patients. In the following two parts of the article, the most important complementary and alternative therapies cancer patients use nowadays are presented and assessed according to published evidence.

Effects of fatigue on bilateral ground reaction force asymmetries during the squat exercise.

Science.gov (United States)

Hodges, Stephanie J; Patrick, Ryan J; Reiser, Raoul F

2011-11-01

Physical performance and injury risk have been related to functional asymmetries of the lower extremity. The effect of fatigue on asymmetries is not well understood. The goal of this investigation was to examine asymmetries during fatiguing repetitions and sets of the free-weight barbell back squat exercise. Seventeen healthy recreationally trained men and women (age = 22.3 ± 2.5 years; body mass = 73.4 ± 13.8 kg; squat 8 repetition maximum [8RM] = 113 ± 35% body mass [mean ± SD]) performed 5 sets of 8 repetitions with 90% 8RM while recording bilateral vertical ground reaction force (GRFv). The GRFv asymmetry during the first 2 (R1 and R2) and the last 2 (R7 and R8) repetitions of each set was calculated by subtracting the % load on the right foot from that of the left foot. Most subjects placed more load on their left foot (also their preferred non-kicking foot). Average absolute asymmetry level across all sets was 4.3 ± 2.5 and 3.6 ± 2.3% for R1 and R2 and R7 and R8, respectively. There were no effects of fatigue on GRFv asymmetries in whole-group analysis (n = 17). However, when initially highly symmetric subjects (±1.7% Left-Right) were removed, average absolute GRFv asymmetry dropped from the beginning to the end of a set (n = 12, p = 0.044) as did peak instantaneous GRFv asymmetry when exploring general shifts toward the left or right leg (n = 12, p = 0.042). The GRFv asymmetries were highly repeatable for 8 subjects that repeated the protocol (Cronbach's α ≥ 0.733, p ≤ 0.056). These results suggest that functional asymmetries, though low, are present in healthy people during the squat exercise and remain consistent. Asymmetries do not increase with fatigue, potentially even decreasing, suggesting that healthy subjects load limbs similarly as fatigue increases, exposing each to similar training stimuli.

Quantitative facial asymmetry: using three-dimensional photogrammetry to measure baseline facial surface symmetry.

Science.gov (United States)

Taylor, Helena O; Morrison, Clinton S; Linden, Olivia; Phillips, Benjamin; Chang, Johnny; Byrne, Margaret E; Sullivan, Stephen R; Forrest, Christopher R

2014-01-01

Although symmetry is hailed as a fundamental goal of aesthetic and reconstructive surgery, our tools for measuring this outcome have been limited and subjective. With the advent of three-dimensional photogrammetry, surface geometry can be captured, manipulated, and measured quantitatively. Until now, few normative data existed with regard to facial surface symmetry. Here, we present a method for reproducibly calculating overall facial symmetry and present normative data on 100 subjects. We enrolled 100 volunteers who underwent three-dimensional photogrammetry of their faces in repose. We collected demographic data on age, sex, and race and subjectively scored facial symmetry. We calculated the root mean square deviation (RMSD) between the native and reflected faces, reflecting about a plane of maximum symmetry. We analyzed the interobserver reliability of the subjective assessment of facial asymmetry and the quantitative measurements and compared the subjective and objective values. We also classified areas of greatest asymmetry as localized to the upper, middle, or lower facial thirds. This cluster of normative data was compared with a group of patients with subtle but increasing amounts of facial asymmetry. We imaged 100 subjects by three-dimensional photogrammetry. There was a poor interobserver correlation between subjective assessments of asymmetry (r = 0.56). There was a high interobserver reliability for quantitative measurements of facial symmetry RMSD calculations (r = 0.91-0.95). The mean RMSD for this normative population was found to be 0.80 ± 0.24 mm. Areas of greatest asymmetry were distributed as follows: 10% upper facial third, 49% central facial third, and 41% lower facial third. Precise measurement permitted discrimination of subtle facial asymmetry within this normative group and distinguished norms from patients with subtle facial asymmetry, with placement of RMSDs along an asymmetry ruler. Facial surface symmetry, which is poorly assessed

Hemispheric asymmetry in the influence of language on visual perception.

Science.gov (United States)

Sun, Yanliang; Cai, Yongchun; Lu, Shena

2015-07-01

Many studies have shown that language can affect visual perception; however, our understanding of the neural basis of linguistic influence is inadequate. This can be investigated by examining the hemispheric asymmetry of linguistic influence. The left and right hemispheres are dominant in close and distant semantic processing, respectively. In this study, we investigated whether the hemispheric asymmetry of semantic processing led to hemispheric asymmetry for concept priming on the detection of objects degraded by continuous flash suppression. We combined a priming paradigm with the divided visual field paradigm and used continuous flash suppression, which renders objects invisible. The results indicated that the hemispheric asymmetry of semantic processing led to a right lateralization in the influence of more abstract concepts on visual perception. The lateralization of brain connectomes may be the underlying neural basis of this effect. Copyright © 2015 Elsevier Inc. All rights reserved.

[Perception of asymmetry smile: Attempt to evaluation through Photoshop].

Science.gov (United States)

Diakite, C; Diep, D; Labbe, D

2016-04-01

In the labial palliative surgery of facial paralysis, it can persist asymmetry smile. Evaluate the impact of an augmentation or reduction of the commissural course on the perception of a smile anomaly, and determine from which asymmetry threshold, the smile is estimated unsightly. We took a picture of two people with a smile not forced; including one with a "cuspid smile", and the another one with a "Mona Lisa" smile. The pictures obtained were modified by the Photoshop software, to simulate an asymmetry labial smile. The changes were related to the move of the left labial commissure, the left nasolabial furrow, and the left cheek using under-correction and overcorrection, every 4 mm. Three pictures with under-correction and four pictures with over-correction were obtained. These smiles were shown to three groups of five people, which included doctors in smile specialties, doctors in other specialties, and non-doctors. Participants were then asked to indicate on which of the pictures, the smile seemed abnormal. Between -8 mm under-correction, and +8 mm over-correction, the asymmetry of the commissural course does not hinder the perception of smile. In the labial palliative surgery of facial paralysis, in the case of persistent asymmetry, there is a tolerance in the perception of "normality" of smile concerning the amplitude of the commissural course going up to 8 mm of asymmetric with under-correction or over-correction. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Cerebral oxygen metabolism and cerebral blood flow in man during light sleep (stage 2)

DEFF Research Database (Denmark)

Madsen, P L; Schmidt, J F; Holm, S

1991-01-01

. They differ in respect of arousal threshold as a stronger stimulus is required to awaken a subject from deep sleep as compared to light sleep. Our results suggest that during non-rapid eye movement sleep cerebral metabolism and thereby cerebral synaptic activity is correlated to cerebral readiness rather than...

[Epidemiological study of dental and facial asymmetries in a sample of preschool subjects].

Science.gov (United States)

Vitale, Marina Consuelo; Barbieri, Federica; Ricotta, Riccardo; Arpesella, Marisa; Emanuelli, Maria Teresa

2015-01-01

to identify the typologies of facial and dental asymmetries in a sample of children aged between 3 and 6 years and to correlate these asymmetries with possible morphological and functional situations. cross-sectional observational study. sample of 95 subjects aged between 3 and 6 years. Clinical data were collected in 10 sessions conducted during school hours in April 2013 by a doctor of Dentistry at two preschools in the city of Sanremo (Liguria Region, Northern Italy) and a kindergarten in the city of Pavia (Lombardy Region, Northern Italy). To collect the data, a weighted clinical questionnaire was used. presence and type of bad habit, type of breathing, presence and type of facial asymmetry, dental formula, presence of diastema, presence and type of occlusal asymmetries, presence and type of dental malocclusions. analysed sample consisted of 53.7% (51/95) of males and 46.3 % (44/95) females; the mean age was 4.3 ± 0.9 years. Most frequent facial asymmetry is orbits asymmetry (35%, 33/95); dental malocclusions are detected in 70%(67/95) of cases. High percentage of subjects (69.5%, 66/95) presents displacement between superior dental midline (SDM) and inferior dental midline (IDM). Several statistically significant associations are observed: in particular, asymmetry of molar ratios is linked to asymmetry of the cheekbones and displacement of the SDM; facial midline has statistical association with asymmetry of the cheekbones (p habits observed and the close correlation between: the presence of dental malocclusions and the presence of compromising habits, the presence of dental malocclusions and the presence of oral breathing.

Frontal Brain Asymmetry and Willingness to Pay

Directory of Open Access Journals (Sweden)

Thomas Z. Ramsøy

2018-03-01

Full Text Available Consumers frequently make decisions about how much they are willing to pay (WTP for specific products and services, but little is known about the neural mechanisms underlying such calculations. In this study, we were interested in testing whether specific brain activation—the asymmetry in engagement of the prefrontal cortex—would be related to consumer choice. Subjects saw products and subsequently decided how much they were willing to pay for each product, while undergoing neuroimaging using electroencephalography. Our results demonstrate that prefrontal asymmetry in the gamma frequency band, and a trend in the beta frequency band that was recorded during product viewing was significantly related to subsequent WTP responses. Frontal asymmetry in the alpha band was not related to WTP decisions. Besides suggesting separate neuropsychological mechanisms of consumer choice, we find that one specific measure—the prefrontal gamma asymmetry—was most strongly related to WTP responses, and was most coupled to the actual decision phase. These findings are discussed in light of the psychology of WTP calculations, and in relation to the recent emergence of consumer neuroscience and neuromarketing.

Frontal Brain Asymmetry and Willingness to Pay

Science.gov (United States)

Ramsøy, Thomas Z.; Skov, Martin; Christensen, Maiken K.; Stahlhut, Carsten

2018-01-01

Consumers frequently make decisions about how much they are willing to pay (WTP) for specific products and services, but little is known about the neural mechanisms underlying such calculations. In this study, we were interested in testing whether specific brain activation—the asymmetry in engagement of the prefrontal cortex—would be related to consumer choice. Subjects saw products and subsequently decided how much they were willing to pay for each product, while undergoing neuroimaging using electroencephalography. Our results demonstrate that prefrontal asymmetry in the gamma frequency band, and a trend in the beta frequency band that was recorded during product viewing was significantly related to subsequent WTP responses. Frontal asymmetry in the alpha band was not related to WTP decisions. Besides suggesting separate neuropsychological mechanisms of consumer choice, we find that one specific measure—the prefrontal gamma asymmetry—was most strongly related to WTP responses, and was most coupled to the actual decision phase. These findings are discussed in light of the psychology of WTP calculations, and in relation to the recent emergence of consumer neuroscience and neuromarketing. PMID:29662432

The Magnetism of Power in Helping Relationships. Professional Attitude and Asymmetry

OpenAIRE

Schuyt, Theo N.M.

2004-01-01

What makes helping relationships - or social interventions in general - so sensitive to abuse? These problems are directly related to the nature of the helping relationship. The core of this relationship is the inequality, the asymmetry, between the helper and the person being helped, and the dependence of the latter. Asymmetry is the driving force behind every social intervention and at the same time its weakest point. Handling asymmetry in an appropriate manner constitutes a major part of t...

Left-right asymmetry of maturation rates in human embryonic neural development

OpenAIRE

De Kovel, C.; Lisgo, S.; Karlebach, G.; Ju, J.; Cheng, G.; Fisher, S.; Francks, C.

2017-01-01

Background Left-right asymmetry is a fundamental organizing feature of the human brain, and neuro-psychiatric disorders such as schizophrenia sometimes involve alterations of brain asymmetry. As early as 8 weeks post conception, the majority of human fetuses move their right arms more than their left arms, but because nerve fibre tracts are still descending from the forebrain at this stage, spinal-muscular asymmetries are likely to play an important developmental role. Methods We used RNA seq...

Asymmetries of Knowledge and Epistemic Change in Social Gaming Interaction

Science.gov (United States)

Piirainen-Marsh, Arja; Tainio, Liisa

2014-01-01

While a growing number of studies investigate the role of knowledge and interactional management of knowledge asymmetries in conversation analysis, the epistemic organization of multilingual and second language interactions is still largely unexplored. This article addresses this issue by investigating how knowledge asymmetries and changing…

Information Asymmetries as Trade Barriers: ISO 9000 Increases International Commerce

Science.gov (United States)

Potoski, Matthew; Prakash, Aseem

2009-01-01

Spatial, cultural, and linguistic barriers create information asymmetries between buyers and sellers that impede international trade. The International Organization for Standardization's ISO 9000 program is designed to reduce these information asymmetries by providing assurance about the product quality of firms that receive its certification.…

Evaluation of ocular acupuncture on cerebral infarction with cerebral blood flow perfusion imaging

International Nuclear Information System (INIS)

Li Yuge; Gao Qinyi; Wang Shuang; Zhao Yong

2008-01-01

To evaluate the immediate effect of ocular acupuncture on patients, an method of SPECT image of cerebral blood flow daily stress test was established. 10 patients diagnosed as cerebral infarction by CT or MRI were tested. They all received 99 Tc m -ECD SPECT imaging at twice before and after ocular acupuncture. By means of image subtraction technique and semi-quantitative method of regional interesting area, the change of regional cerebral blood flow was observed between the two images. Under restful state perfusion of cerebral blood flow in 18 foci was low at the frontal lobe, the cerebellum, the basal ganglia and temporal lobe. After ocular acupuncture, the perfusions were obviously increased in 16 foci among them and the reactivity of the frontal lobe and the cerebellum to ocular acupuncture was higher, the average improvement rate of which was 55.15% and 53.06% respectively, lower in the basal ganglia and temporal lobe, the average improvement rate was 31.79% and 36.67% respectively. 99 Tc m -ECD SPECT cerebral perfusion image has some significant clinic value for evaluating the effect of ocular acupuncture to treating cerebral infarction. (authors)

The small mixing angle $\\theta_{13}$ and the lepton asymmetry

CERN Document Server

Lee, S H; Lee, Song-Haeng; Siyeon, Kim

2005-01-01

We present the correlation of low energy CP phases, both Dirac and Majorana, and the lepton asymmetry for the baryon asymmetry in the universe, with a certain class of Yukawa matrices that consist of two right-handed neutrinos and include one texture zero in themselves. For cases in which the amount of the lepton asymmetry $Y_L$ turns out to be proportional to $\\theta_{13}^2$, we consider the relation between two types of CP phases and the relation of $Y_L$ versus the Jarlskog invariant or the amplitude of neutrinoless double beta decay as $\\theta_{13}$ varies.

Relating the baryon asymmetry to the thermal relic dark matter density

International Nuclear Information System (INIS)

McDonald, John

2011-01-01

We present a generic framework, baryomorphosis, which modifies the baryon asymmetry to be naturally of the order of a typical thermal relic weakly interacting massive particle (WIMP) density. We consider a simple scalar-based model to show how this is possible. This model introduces a sector in which a large initial baryon asymmetry is injected into particles ('annihilons'), φ B , φ-circumflex B , of mass ∼100 GeV-1 TeV. φ B φ-circumflex B annihilations convert the initial φ B , φ-circumflex B asymmetry to a final asymmetry with a thermal relic WIMP-like density. This subsequently decays to a conventional baryon asymmetry whose magnitude is naturally related to the density of thermal relic WIMP dark matter. In this way the two coincidences of baryons and dark matter, i.e. why their densities are similar to each other and why they are both similar to a WIMP thermal relic density (the 'WIMP miracle'), may be understood. The model may be tested by the production of annihilons at colliders.

A full picture of large lepton number asymmetries of the Universe

Energy Technology Data Exchange (ETDEWEB)

Barenboim, Gabriela [Departament de Física Teòrica and IFIC, Universitat de València-CSIC, C/ Dr. Moliner, 50, Burjassot, E-46100 Spain (Spain); Park, Wan-Il, E-mail: Gabriela.Barenboim@uv.es, E-mail: wipark@jbnu.ac.kr [Department of Science Education (Physics), Chonbuk National University, 567 Baekje-daero, Jeonju, 561-756 (Korea, Republic of)

2017-04-01

A large lepton number asymmetry of O(0.1−1) at present Universe might not only be allowed but also necessary for consistency among cosmological data. We show that, if a sizeable lepton number asymmetry were produced before the electroweak phase transition, the requirement for not producing too much baryon number asymmetry through sphalerons processes, forces the high scale lepton number asymmetry to be larger than about 03. Therefore a mild entropy release causing O(10-100) suppression of pre-existing particle density should take place, when the background temperature of the Universe is around T = O(10{sup −2}-10{sup 2}) GeV for a large but experimentally consistent asymmetry to be present today. We also show that such a mild entropy production can be obtained by the late-time decays of the saxion, constraining the parameters of the Peccei-Quinn sector such as the mass and the vacuum expectation value of the saxion field to be m {sub φ} ∼> O(10) TeV and φ{sub 0} ∼> O(10{sup 14}) GeV, respectively.

Study of cerebral vascular diseases with radioisotopes in cerebral atherosclerotical subjects and/for subjects with sequelae of cerebral stroke, before and after use of the association piracetam-dihydroergotoxine

International Nuclear Information System (INIS)

Lara, P.F.; Ferreira, A.; Paulillo, L.F.; Cukierman, M.

1985-01-01

Twently subjects with cerebral sclerosis and/or sequelas of cerebral stroke were studied, before and after use of piracetam-dihydroergotoxine. We performed the complete hemispheric cerebral blood flow and cerebral scintigraphy, beyond clinical and neurological examination. Scintigraphies were unchanged. Cerebral circulation times, or both hemispheres, diminished. This occurred, probably, in relation with metabolic effects of both pharmaceutical drugs. The alpha sympatolytic and modulatory effects of dihydroergotoxine should be considered. (author) [pt

MANDIBULAR ASYMMETRY CHARACTERIZATION USING GENERALIZED TENSOR-BASED MORPHOMETRY.

Science.gov (United States)

Paniagua, Beatriz; Alhadidi, Abeer; Cevidanes, Lucia; Styner, Martin; Oguz, Ipek

2011-12-31

Quantitative assessment of facial asymmetry is crucial for successful planning of corrective surgery. We propose a tensor-based morphometry (TBM) framework to locate and quantify asymmetry using 3D CBCT images. To this end, we compute a rigid transformation between the mandible segmentation and its mirror image, which yields global rotation and translation with respect to the cranial base to guide the surgery's first stage. Next, we nonrigidly register the rigidly aligned images and use TBM methods to locally analyze the deformation field. This yields data on the location, amount and direction of "growth" (or "shrinkage") between the left and right sides. We visualize this data in a volumetric manner and via scalar and vector maps on the mandibular surface to provide the surgeon with optimal understanding of the patient's anatomy. We illustrate the feasibility and strength of our technique on 3 representative patients with a wide range of facial asymmetries.

The beta decay asymmetry parameter of 35Ar

International Nuclear Information System (INIS)

Garnett, J.D.

1987-11-01

The beta decay asymmetry parameter for 35 Ar = 35 Cl + e + + nu/sub e/ has been remeasured in order to resolve a long standing puzzle. Previous asymmetry measurements, when combined with the comparative half-life, yield a value for the vector coupling constant, G/sub v/, that is in serious disagreement with the accepted value. We produced polarized 35 Ar by a (p,n) reaction on 35 Cl using the polarized proton beam provided by Lawrence Berkeley Laboratory's 88-Inch Cyclotron. The polarization of the 35 Ar was determined by measuring the asymmetry of the positrons produced in 35 Ar decay to the first excited state in 35 Cl (branching ratio = 1.3%) in coincidence with a 1219.4 keV gamma ray. Our result, A 0 = 0.49 +- 0.10, combined with the comparative half-life yields a value for G/sub v/ in agreement with the accepted value

Human subcortical brain asymmetries in 15,847 people worldwide reveal effects of age and sex.

Science.gov (United States)

Guadalupe, Tulio; Mathias, Samuel R; vanErp, Theo G M; Whelan, Christopher D; Zwiers, Marcel P; Abe, Yoshinari; Abramovic, Lucija; Agartz, Ingrid; Andreassen, Ole A; Arias-Vásquez, Alejandro; Aribisala, Benjamin S; Armstrong, Nicola J; Arolt, Volker; Artiges, Eric; Ayesa-Arriola, Rosa; Baboyan, Vatche G; Banaschewski, Tobias; Barker, Gareth; Bastin, Mark E; Baune, Bernhard T; Blangero, John; Bokde, Arun L W; Boedhoe, Premika S W; Bose, Anushree; Brem, Silvia; Brodaty, Henry; Bromberg, Uli; Brooks, Samantha; Büchel, Christian; Buitelaar, Jan; Calhoun, Vince D; Cannon, Dara M; Cattrell, Anna; Cheng, Yuqi; Conrod, Patricia J; Conzelmann, Annette; Corvin, Aiden; Crespo-Facorro, Benedicto; Crivello, Fabrice; Dannlowski, Udo; de Zubicaray, Greig I; de Zwarte, Sonja M C; Deary, Ian J; Desrivières, Sylvane; Doan, Nhat Trung; Donohoe, Gary; Dørum, Erlend S; Ehrlich, Stefan; Espeseth, Thomas; Fernández, Guillén; Flor, Herta; Fouche, Jean-Paul; Frouin, Vincent; Fukunaga, Masaki; Gallinat, Jürgen; Garavan, Hugh; Gill, Michael; Suarez, Andrea Gonzalez; Gowland, Penny; Grabe, Hans J; Grotegerd, Dominik; Gruber, Oliver; Hagenaars, Saskia; Hashimoto, Ryota; Hauser, Tobias U; Heinz, Andreas; Hibar, Derrek P; Hoekstra, Pieter J; Hoogman, Martine; Howells, Fleur M; Hu, Hao; Hulshoff Pol, Hilleke E; Huyser, Chaim; Ittermann, Bernd; Jahanshad, Neda; Jönsson, Erik G; Jurk, Sarah; Kahn, Rene S; Kelly, Sinead; Kraemer, Bernd; Kugel, Harald; Kwon, Jun Soo; Lemaitre, Herve; Lesch, Klaus-Peter; Lochner, Christine; Luciano, Michelle; Marquand, Andre F; Martin, Nicholas G; Martínez-Zalacaín, Ignacio; Martinot, Jean-Luc; Mataix-Cols, David; Mather, Karen; McDonald, Colm; McMahon, Katie L; Medland, Sarah E; Menchón, José M; Morris, Derek W; Mothersill, Omar; Maniega, Susana Munoz; Mwangi, Benson; Nakamae, Takashi; Nakao, Tomohiro; Narayanaswaamy, Janardhanan C; Nees, Frauke; Nordvik, Jan E; Onnink, A Marten H; Opel, Nils; Ophoff, Roel; Paillère Martinot, Marie-Laure; Papadopoulos Orfanos, Dimitri; Pauli, Paul; Paus, Tomáš; Poustka, Luise; Reddy, Janardhan Yc; Renteria, Miguel E; Roiz-Santiáñez, Roberto; Roos, Annerine; Royle, Natalie A; Sachdev, Perminder; Sánchez-Juan, Pascual; Schmaal, Lianne; Schumann, Gunter; Shumskaya, Elena; Smolka, Michael N; Soares, Jair C; Soriano-Mas, Carles; Stein, Dan J; Strike, Lachlan T; Toro, Roberto; Turner, Jessica A; Tzourio-Mazoyer, Nathalie; Uhlmann, Anne; Hernández, Maria Valdés; van den Heuvel, Odile A; van der Meer, Dennis; van Haren, Neeltje E M; Veltman, Dick J; Venkatasubramanian, Ganesan; Vetter, Nora C; Vuletic, Daniella; Walitza, Susanne; Walter, Henrik; Walton, Esther; Wang, Zhen; Wardlaw, Joanna; Wen, Wei; Westlye, Lars T; Whelan, Robert; Wittfeld, Katharina; Wolfers, Thomas; Wright, Margaret J; Xu, Jian; Xu, Xiufeng; Yun, Je-Yeon; Zhao, JingJing; Franke, Barbara; Thompson, Paul M; Glahn, David C; Mazoyer, Bernard; Fisher, Simon E; Francks, Clyde

2017-10-01

The two hemispheres of the human brain differ functionally and structurally. Despite over a century of research, the extent to which brain asymmetry is influenced by sex, handedness, age, and genetic factors is still controversial. Here we present the largest ever analysis of subcortical brain asymmetries, in a harmonized multi-site study using meta-analysis methods. Volumetric asymmetry of seven subcortical structures was assessed in 15,847 MRI scans from 52 datasets worldwide. There were sex differences in the asymmetry of the globus pallidus and putamen. Heritability estimates, derived from 1170 subjects belonging to 71 extended pedigrees, revealed that additive genetic factors influenced the asymmetry of these two structures and that of the hippocampus and thalamus. Handedness had no detectable effect on subcortical asymmetries, even in this unprecedented sample size, but the asymmetry of the putamen varied with age. Genetic drivers of asymmetry in the hippocampus, thalamus and basal ganglia may affect variability in human cognition, including susceptibility to psychiatric disorders.

Interhemispheric Asymmetry in the Mesosphere and Lower Thermosphere Observed by SABER/TIMED

Science.gov (United States)

Yee, J. H.

2017-12-01

In this paper we analyze nearly 15 years of satellite observations of temperature, airglow, and composition in the Mesosphere and Lower Thermosphere (MLT) to quantify their interhemispheric asymmetries ao one can provide quantitative links between observed asymmetries and the spatial and temporal variations of the gravity wave activity. Two processes are believed to be responsible for observed interhemispheric differences in the MLT. The first is the direct radiation effect from the eccentricity of the Earth orbit amd the other is the difference in gravity wave source distribution and filtering due to asymmetries in mean winds of the lower atmosphere. Both processes have been theoretically investigated to explain the observed asymmetry in some of the atmospheric parameters, but not self-consistently in all observed parameters together. In this paper we will show the asymmetry in the time-varying zonal-mean latitudinal structures of temperature, airglow emission rate, and composition observed by TIMED/SABER. We will quantify their interhemispheric asymmetries for different seasons under different solar activity conditions. In addition, temperature measurements will also be used to obtain temporal and spatial morphology of gravity wave potential energies. We will interpret the asymmetry in the observed fields and examine qualitatively their consistency with the two responsible processes, especially the one due to gravity wave filtering process. Our goal is to introduce and to share the spatial and temporal morphologies of all the observed fields to the modeling community so, together self-consistently, they be can be used to gain physical insights into the relative importance of various drivers responsible for the observed asymmetry, especially the role of gravity wave induced eddy drag and mixing, a critical, but least quantitatively understood process.

Tension-compression asymmetry modelling: strategies for anisotropy parameters identification.

Directory of Open Access Journals (Sweden)

Barros Pedro

2016-01-01

Full Text Available This work presents details concerning the strategies and algorithms adopted in the fully implicit FE solver DD3IMP to model the orthotropic behavior of metallic sheets and the procedure for anisotropy parameters identification. The work is focused on the yield criterion developed by Cazacu, Plunkett and Barlat, 2006 [1], which accounts for both tension–compression asymmetry and orthotropic plastic behavior. The anisotropy parameters for a 2090-T3 aluminum alloy are identified accounting, or not, for the tension-compression asymmetry. The numerical simulation of a cup drawing is performed for this material, highlighting the importance of considering tension-compression asymmetry in the prediction of the earing profile, for materials with cubic structure, even if this phenomenon is relatively small.

North–South Asymmetry of the Rotation of the Solar Magnetic Field

Science.gov (United States)

Xie, Jinglan; Shi, Xiangjun; Qu, Zhining

2018-03-01

Using the rotation rates of the solar magnetic field during solar cycles 21 to 23 obtained by Chu et al. by analyzing the synoptic magnetic maps produced by the NSO/Kitt Peak and SOHO/MDI during the years 1975 to 2008, the temporal variation of the equatorial rotation rate (A) and the latitude gradient of rotation (B) in the northern and southern hemispheres are studied separately. The results indicate that the rotation is more differential (about 4.3%) in the southern hemisphere in the considered time frame. It is found that the north–south asymmetry of A and the asymmetry of B show increasing trends in the considered time frame, while the north–south asymmetry of the solar activity shows a decreasing trend. There exists a significant negative correlation (at 95% confidence level) between the asymmetry of B and the asymmetry of the solar activity, and this may be due to stronger magnetic activity in a certain hemisphere that may suppress the differential rotation to some extent. The periodicities in the variation of A and B are also studied, and periods of about 5.0 and 10.5 yr (5.5 and 10.4 yr) can be found for the variation of the northern (southern) hemisphere B. Moreover, the north–south asymmetry of A and the asymmetry of B have similar periods of about 2.6–2.7 and 5.2–5.3 yr. Further, cross-correlation analysis indicates that there exists a phase difference (about eight months) between the northern and southern hemisphere B, and this means that the northern hemisphere B generally leads by about eight months.

Head, withers and pelvic movement asymmetry and their relative timing in trot in racing Thoroughbreds in training.

Science.gov (United States)

Pfau, T; Noordwijk, K; Sepulveda Caviedes, M F; Persson-Sjodin, E; Barstow, A; Forbes, B; Rhodin, M

2018-01-01

Horses show compensatory head movement in hindlimb lameness and compensatory pelvis movement in forelimb lameness but little is known about the relationship of withers movement symmetry with head and pelvic asymmetry in horses with naturally occurring gait asymmetries. To document head, withers and pelvic movement asymmetry and timing differences in horses with naturally occurring gait asymmetries. Retrospective analysis of gait data. Head, withers and pelvic movement asymmetry and timing of displacement minima and maxima were quantified from inertial sensors in 163 Thoroughbreds during trot-ups on hard ground. Horses were divided into 4 subgroups using the direction of head and withers movement asymmetry. Scatter plots of head vs. pelvic movement asymmetry illustrated how the head-withers relationship distinguishes between contralateral and ipsilateral head-pelvic movement asymmetry. Independent t test or Mann-Whitney U test (Pmovement asymmetry and timing differences between groups. The relationship between head and withers asymmetry (i.e. same sided or opposite sided asymmetry) predicts the relationship between head and pelvic asymmetry in 69-77% of horses. Pelvic movement symmetry was significantly different between horses with same sign vs. opposite sign of head-withers asymmetry (Pmovement asymmetry identifies the majority of horses with ipsilateral and contralateral head and pelvic movement asymmetries. Withers movement should be further investigated for differentiating between forelimb and hindlimb lame horses. Horses with opposite sided head and withers asymmetry significantly delay the upward movement of the head after 'sound' forelimb stance. © 2017 The Authors. Equine Veterinary Journal published by John Wiley & Sons Ltd on behalf of EVJ Ltd.

A new genus of long-legged flies displaying remarkable wing directional asymmetry

Science.gov (United States)

Justin B. Runyon; Richard L. Hurley

2004-01-01

A previously unknown group of flies is described whose males exhibit directional asymmetry, in that the left wing is larger than, and of a different shape from, the right wing. To our knowledge, wing asymmetry of this degree has not previously been reported in an animal capable of flight. Such consistent asymmetry must result from a left­right axis during development...

On the bilateral asymmetry during running and cycling - a review considering leg preference.

Science.gov (United States)

Carpes, Felipe P; Mota, Carlos B; Faria, Irvin E

2010-11-01

This review summarizes the effects of bilateral asymmetry on running and cycling performance and risk of injury in healthy subjects and the influence of leg preference. We define the term leg preference derived from lateral preference as representative of the choice for one side of the body to perform a motor action. Useful information is provided for biomechanical and physiological research and coaching with relevance to an understanding regarding the occurrence of lower limb asymmetry. To provide a synopsis of what is known about bilateral asymmetry in human running and cycling and its relationship to limb preference, especially in the context of competitive sport performance and risk of injury. Structured narrative review. The relationship between asymmetry and lower limb preference was reviewed using Medline(®), Sciencedirect(®), and Scopus(®) search engines considering studies published in English until June 2009. The environment characteristics may influence running asymmetries, which are more frequent in angular parameters. Environment characteristics are related to ground irregularities requiring compensatory movements changing the mechanical workload on joints and bones, which may influence asymmetries in biomechanical parameters between lower limbs. The relationship between asymmetry and injury risk should be assessed with caution since running speed may influence asymmetry in injured and non-injured subjects who often show similar asymmetry levels. Symmetry can be improved with increasing running speed. In addition to running speed, coaches and athletes interested in minimizing lateral difference should consider a training regime aimed at correcting asymmetry which may negatively affect running technique by influencing the compensatory movements that an athlete usually performs. During cycling, bilateral differences are frequently found and vary with the competitive situation, pedaling cadence, exercise intensity and exercise duration. Regardless of

Prediction of cerebral ischemia due to cerebral vasospasm in SAH using SPECT and 123I-IMP with acetazolamide test

International Nuclear Information System (INIS)

Nakagawara, Jyoji; Wada, Keiji; Takeda, Rihei; Usami, Takashi; Hashimoto, Ikuo; Shimazaki, Mitsuteru; Tanaka, Chiharu; Nakamura, Jun-ichi; Suematsu, Katsumi.

1989-01-01

To investigate the possibility of predicting cerebral ischemia due to cerebral vasospasm in subarachnoid hemorrhage (SAH), serial evaluation of the cerebral vasodilatory capacity by the acetazolamide test was conducted, using single photon emission computed tomography (SPECT) and N-isopropyl 123 I-p-iodoamphetamine (IMP), in 17 patients with cerebral vasospasm following early surgery for ruptured aneurysms. The degree of vasospasm measured on the angiograms was classified into the following three types; mild degree (25%>stenosis), moderate degree (25∼50% stenosis), and severe degree(50%cerebral vasodilatory capacity was preserved at the normal level during the period of vasospasm. In eight patients with asymptomatic vasospasm (moderate degree), a transient limitation of cerebral vasodiratory capacity was observed between the 6th and 16th day after a rupture of the cerebral aneurysm. In five patients with symptomatic vasospasm resulting in reversible ischemia, a marked limitation of cerebral vasodilatory capacity was noted between the 7th and 15th day, and a delayed recovery of cerebral vasodilatory capacity was observed. This reversibility of cerebral vasodilatory capacity in patients with cerebral vasospasm suggests that a local decrease of purfusion pressure due to cerebral vasospasm causes compensatory vasodilation of intraparenchymal arteries and the vasodilatory reaction to acetazolamide was limited until the release of the cerebral vasospasm. Therefore, assessment of cerebral vasodilatory capacity in SAH by the acetazolamide test might predict the appearance and continuation of potential ischemia of the brain caused by the reduction of perfusion pressure due to cerebral vasospasm. (J.P.N.)

A hemispherical power asymmetry from inflation

International Nuclear Information System (INIS)

Erickcek, Adrienne L.; Kamionkowski, Marc; Carroll, Sean M.

2008-01-01

Measurements of cosmic microwave background temperature fluctuations by the Wilkinson Microwave Anisotropy Probe indicate that the fluctuation amplitude in one half of the sky differs from the amplitude in the other half. We show that such an asymmetry cannot be generated during single-field slow-roll inflation without violating constraints to the homogeneity of the Universe. In contrast, a multifield inflationary theory, the curvaton model, can produce this power asymmetry without violating the homogeneity constraint. The mechanism requires the introduction of a large-amplitude superhorizon perturbation to the curvaton field, possibly a preinflationary remnant or a superhorizon curvaton-web structure. The model makes several predictions, including non-Gaussianity and modifications to the inflationary consistency relation, that will be tested with forthcoming cosmic microwave background experiments.

Frontal brain asymmetry in adult attention-deficit/hyperactivity disorder (ADHD): extending the motivational dysfunction hypothesis.

Science.gov (United States)

Keune, Philipp M; Wiedemann, Eva; Schneidt, Alexander; Schönenberg, Michael

2015-04-01

Attention-deficit/hyperactivity disorder (ADHD) involves motivational dysfunction, characterized by excessive behavioral approach tendencies. Frontal brain asymmetry in the alpha band (8-13 Hz) in resting-state electroencephalogram (EEG) represents a neural correlate of global motivational tendencies, and abnormal asymmetry, indicating elevated approach motivation, was observed in pediatric and adult patients. To date, the relation between ADHD symptoms, depression and alpha asymmetry, its temporal metric properties and putative gender-specificity remain to be explored. Adult ADHD patients (n=52) participated in two resting-state EEG recordings, two weeks apart. Asymmetry measures were aggregated across recordings to increase trait specificity. Putative region-specific associations between asymmetry, ADHD symptoms and depression, its gender-specificity and test-retest reliability were examined. ADHD symptoms were associated with approach-related asymmetry (stronger relative right-frontal alpha power). Approach-related asymmetry was pronounced in females, and also associated with depression. The latter association was mediated by ADHD symptoms. Test-retest reliability was sufficient. The association between reliably assessable alpha asymmetry and ADHD symptoms supports the motivational dysfunction hypothesis. ADHD symptoms mediating an atypical association between asymmetry and depression may be attributed to depression arising secondary to ADHD. Gender-specific findings require replication. Frontal alpha asymmetry may represent a new reliable marker of ADHD symptoms. Copyright © 2014 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Ozone zonal asymmetry and planetary wave characterization during Antarctic spring

Directory of Open Access Journals (Sweden)

I. Ialongo

2012-03-01

Full Text Available A large zonal asymmetry of ozone has been observed over Antarctica during winter-spring, when the ozone hole develops. It is caused by a planetary wave-driven displacement of the polar vortex. The total ozone data by OMI (Ozone Monitoring Instrument and the ozone profiles by MLS (Microwave Limb Sounder and GOMOS (Global Ozone Monitoring by Occultation of Stars were analysed to characterize the ozone zonal asymmetry and the wave activity during Antarctic spring. Both total ozone and profile data have shown a persistent zonal asymmetry over the last years, which is usually observed from September to mid-December. The largest amplitudes of planetary waves at 65° S (the perturbations can achieve up to 50% of zonal mean values is observed in October. The wave activity is dominated by the quasi-stationary wave 1 component, while the wave 2 is mainly an eastward travelling wave. Wave numbers 1 and 2 generally explain more than the 90% of the ozone longitudinal variations. Both GOMOS and MLS ozone profile data show that ozone zonal asymmetry covers the whole stratosphere and extends up to the altitudes of 60–65 km. The wave amplitudes in ozone mixing ratio decay with altitude, with maxima (up to 50% below 30 km.

The characterization of the ozone zonal asymmetry has become important in the climate research. The inclusion of the polar zonal asymmetry in the climate models is essential for an accurate estimation of the future temperature trends. This information might also be important for retrieval algorithms that rely on ozone a priori information.

An optimal method of moments to measure the charge asymmetry at the Z0

International Nuclear Information System (INIS)

Bruemmer, N.C.

1994-02-01

Parity violation at LEP or SLC can be measured through the charge asymmetry. An optimal method of moments is developed here to measure this asymmetry, as well as similar asymmetries. This method is equivalent to the likelihood fit. It is simpler in use, as it gives analytical formulas for both the asymmetry and its statistical error. These formulas give the dependence of the accuracy on the experimental angular acceptance explicitly. (orig.)

Effects of intermittent theta burst stimulation on cerebral blood flow and cerebral vasomotor reactivity.

Science.gov (United States)

Pichiorri, Floriana; Vicenzini, Edoardo; Gilio, Francesca; Giacomelli, Elena; Frasca, Vittorio; Cambieri, Chiara; Ceccanti, Marco; Di Piero, Vittorio; Inghilleri, Maurizio

2012-08-01

To determine whether intermittent theta burst stimulation influences cerebral hemodynamics, we investigated changes induced by intermittent theta burst stimulation on the middle cerebral artery cerebral blood flow velocity and vasomotor reactivity to carbon dioxide (CO(2)) in healthy participants. The middle cerebral artery flow velocity and vasomotor reactivity were monitored by continuous transcranial Doppler sonography. Changes in cortical excitability were tested by transcranial magnetic stimulation. In 11 healthy participants, before and immediately after delivering intermittent theta burst stimulation, we tested cortical excitability measured by the resting motor threshold and motor evoked potential amplitude over the stimulated hemisphere and vasomotor reactivity to CO(2) bilaterally. The blood flow velocity was monitored in both middle cerebral arteries throughout the experimental session. In a separate session, we tested the effects of sham stimulation under the same experimental conditions. Whereas the resting motor threshold remained unchanged before and after stimulation, motor evoked potential amplitudes increased significantly (P = .04). During and after stimulation, middle cerebral artery blood flow velocities also remained bilaterally unchanged, whereas vasomotor reactivity to CO(2) increased bilaterally (P = .04). The sham stimulation left all variables unchanged. The expected intermittent theta burst stimulation-induced changes in cortical excitability were not accompanied by changes in cerebral blood flow velocities; however, the bilateral increased vasomotor reactivity suggests that intermittent theta burst stimulation influences the cerebral microcirculation, possibly involving subcortical structures. These findings provide useful information on hemodynamic phenomena accompanying intermittent theta burst stimulation, which should be considered in research aimed at developing this noninvasive, low-intensity stimulation technique for safe

Determining Complementary Properties with Quantum Clones

Science.gov (United States)

Thekkadath, G. S.; Saaltink, R. Y.; Giner, L.; Lundeen, J. S.

2017-08-01

In a classical world, simultaneous measurements of complementary properties (e.g., position and momentum) give a system's state. In quantum mechanics, measurement-induced disturbance is largest for complementary properties and, hence, limits the precision with which such properties can be determined simultaneously. It is tempting to try to sidestep this disturbance by copying the system and measuring each complementary property on a separate copy. However, perfect copying is physically impossible in quantum mechanics. Here, we investigate using the closest quantum analog to this copying strategy, optimal cloning. The coherent portion of the generated clones' state corresponds to "twins" of the input system. Like perfect copies, both twins faithfully reproduce the properties of the input system. Unlike perfect copies, the twins are entangled. As such, a measurement on both twins is equivalent to a simultaneous measurement on the input system. For complementary observables, this joint measurement gives the system's state, just as in the classical case. We demonstrate this experimentally using polarized single photons.

Polarization asymmetries and gauge theory interactions at short distances

International Nuclear Information System (INIS)

Craigie, N.S.

1983-01-01

In this talk, we give the arguments as to why spin asymmetries test fundamental properties of the underlying gauge theories of elementary particles, concentrating mainly on electro-weak and QCD interactions, but also looking at the future and possible signatures for supersymmetric strong interactions. We also mention briefly the role helicity asymmetry measurements can play as regards higher order corrections, including higher twist, in QCD. (orig./HSI)

Measurement of Charge Asymmetries in Charmless Hadronic B Meson Decays

Energy Technology Data Exchange (ETDEWEB)

Chen, S. [Purdue University, West Lafayette, Indiana 47907 (United States); Fast, J. [Purdue University, West Lafayette, Indiana 47907 (United States); Hinson, J. W. [Purdue University, West Lafayette, Indiana 47907 (United States); Lee, J. [Purdue University, West Lafayette, Indiana 47907 (United States); Menon, N. [Purdue University, West Lafayette, Indiana 47907 (United States); Miller, D. H. [Purdue University, West Lafayette, Indiana 47907 (United States); Shibata, E. I. [Purdue University, West Lafayette, Indiana 47907 (United States); Shipsey, I. P. J. [Purdue University, West Lafayette, Indiana 47907 (United States); Pavlunin, V. [Purdue University, West Lafayette, Indiana 47907 (United States); Cronin-Hennessy, D. [University of Rochester, Rochester, New York 14627 (United States)] (and others)

2000-07-17

We search for CP -violating charge asymmetries (A{sub CP} ) in the B meson decays to K{sup {+-}}{pi}{sup {+-}} , K{sup {+-}}{pi}{sup 0} , K{sup 0}{sub S}{pi}{sup {+-}} , K{sup {+-}}{eta}{sup '} , and {omega}{pi}{sup {+-}} . Using 9.66 million {upsilon}(4S) decays collected with the CLEO detector, the statistical precision on A{sub CP} is in the range of {+-}0.12 to {+-}0.25 depending on decay mode. While CP -violating asymmetries of up to {+-}0.5 are possible within the standard model, the measured asymmetries are consistent with zero in all five decay modes studied. (c) 2000 The American Physical Society.

Complementary Feeding: Review of Recommendations, Feeding Practices and Adequacy of Homemade Complementary Food Preparations in Developing Countries – lessons from Ethiopia

Directory of Open Access Journals (Sweden)

Motuma A Abeshu

2016-10-01

Full Text Available Breastfeeding provides the ideal food during the first 6 months of life. Complementary feeding is the process starting when breast milk alone is no longer sufficient, the target age being between 6 to 23 months. The gap between nutritional requirement and amount obtained from breast milk increases with age. For energy, 200kcal, 300kcal and 550kcal per day is expected to be covered by complementary foods at 6-8, 9-11 and 12-23 months, respectively. In addition, the complementary foods must provide relatively large proportions of micronutrients such as: iron, zinc, phosphorus, magnesium, calcium and vitamin B6. In several parts of the developing world, complementary feeding continues as a challenge to good nutrition in children. In Ethiopia, only 4.2% of breastfed children of 6–23 months of age have a minimum acceptable diet. The gaps are mostly attributed to either poor dietary quality or poor feeding practices, if not both. Commercial fortified foods are often beyond the reach of the poor. Thus, homemade complementary foods remain commonly used. However, unfortified complementary foods that are predominantly plant-based provide insufficient amounts of key nutrients (particularly iron, zinc and calcium during the age of 6 – 23 months even, when based on an improved recipe. This review thus assessed complementary feeding practice and recommendation and reviewed the level of adequacy of homemade complementary foods.

A new metric of the low-mode asymmetry for ignition target designs

International Nuclear Information System (INIS)

Gu, Jianfa; Dai, Zhensheng; Fan, Zhengfeng; Zou, Shiyang; Ye, Wenhua; Pei, Wenbing; Zhu, Shaoping

2014-01-01

In the deuterium-tritium inertial confinement fusion implosion experiments on the National Ignition Facility, the measured neutron yield and hot spot pressure are significantly lower than simulations. Understanding the underlying physics of the deficit is essential to achieving ignition. This paper investigates the low-mode areal density asymmetry in the main fuel of ignition capsule. It is shown that the areal density asymmetry breaks up the compressed shell and significantly reduces the conversion of implosion kinetic energy to hot spot internal energy, leading to the calculated hot spot pressure and neutron yield quite close to the experimental data. This indicates that the low-mode shell areal density asymmetry can explain part of the large discrepancy between simulations and experiments. Since only using the hot spot shape term could not adequately characterize the effects of the shell areal density asymmetry on implosion performance, a new metric of the low-mode asymmetry is developed to accurately measure the probability of ignition

Asymmetry in food handling behavior of a tree-dwelling rodent (Sciurus vulgaris.

Directory of Open Access Journals (Sweden)

Nuria Polo-Cavia

Full Text Available Asymmetry in motor patterns is present in a wide variety of animals. Many lateralized behaviors seem to depend on brain asymmetry, as it is the case of different tasks associated to food handling by several bird and mammal species. Here, we analyzed asymmetry in handling behavior of pine cones by red squirrels (Sciurus vulgaris. Red squirrels devote most of their daily activity to feeding, thus this species constitutes an appropriate model for studying asymmetry in food processing. We aimed to explore 1 the potential lateralization in handling of pine cones by squirrels, 2 the dominant pattern for this behavior (left- vs. right-handed, and 3 whether this pattern varies among populations and depending on the pine tree species available. Results revealed that red squirrels handle pine cones in an asymmetrical way, and that direction of asymmetry varies among populations and seems to be determined more by local influences rather than by the pine tree species.

Neurally Derived Tissues in Xenopus laevis Embryos Exhibit a Consistent Bioelectrical Left-Right Asymmetry

Directory of Open Access Journals (Sweden)

Vaibhav P. Pai

2012-01-01

Full Text Available Consistent left-right asymmetry in organ morphogenesis is a fascinating aspect of bilaterian development. Although embryonic patterning of asymmetric viscera, heart, and brain is beginning to be understood, less is known about possible subtle asymmetries present in anatomically identical paired structures. We investigated two important developmental events: physiological controls of eye development and specification of neural crest derivatives, in Xenopus laevis embryos. We found that the striking hyperpolarization of transmembrane potential (Vmem demarcating eye induction usually occurs in the right eye field first. This asymmetry is randomized by perturbing visceral left-right patterning, suggesting that eye asymmetry is linked to mechanisms establishing primary laterality. Bilateral misexpression of a depolarizing channel mRNA affects primarily the right eye, revealing an additional functional asymmetry in the control of eye patterning by Vmem. The ATP-sensitive K+ channel subunit transcript, SUR1, is asymmetrically expressed in the eye primordia, thus being a good candidate for the observed physiological asymmetries. Such subtle asymmetries are not only seen in the eye: consistent asymmetry was also observed in the migration of differentiated melanocytes on the left and right sides. These data suggest that even anatomically symmetrical structures may possess subtle but consistent laterality and interact with other developmental left-right patterning pathways.

Temporal change of EIA asymmetry revealed by a beacon receiver network in Southeast Asia

Science.gov (United States)

Watthanasangmechai, Kornyanat; Yamamoto, Mamoru; Saito, Akinori; Maruyama, Takashi; Yokoyama, Tatsuhiro; Nishioka, Michi; Ishii, Mamoru

2015-05-01

To reveal the temporal change of the equatorial ionization anomaly (EIA) asymmetry, a multipoint satellite-ground beacon experiment was conducted along the meridional plane of the Thailand-Indonesia sector. The observation includes one station near the magnetic equator and four stations at off-equator latitudes. This is the first EIA asymmetry study with high spatial resolution using GNU Radio Beacon Receiver (GRBR) observations in Southeast Asia. GRBR-total electron contents (TECs) from 97 polar-orbit satellite passes in March 2012 were analyzed in this study. Successive passes captured rapid evolution of EIA asymmetry, especially during geomagnetic disturbances. The penetrating electric fields that occur during geomagnetic disturbed days are not the cause of the asymmetry. Instead, high background TEC associated with an intense electric field empowers the neutral wind to produce severe asymmetry of the EIA. Such rapid evolution of EIA asymmetry was not seen during nighttime, when meridional wind mainly controlled the asymmetric structures. Additional data are necessary to identify the source of the variations, i.e., atmospheric waves. Precisely capturing the locations of the crests and the evolution of the asymmetry enhances understanding of the temporal change of EIA asymmetry at the local scale and leads to a future local modeling for TEC prediction in Southeast Asia.

Socioeconomic Status Is Not Related with Facial Fluctuating Asymmetry: Evidence from Latin-American Populations.

Science.gov (United States)

Quinto-Sánchez, Mirsha; Cintas, Celia; Silva de Cerqueira, Caio Cesar; Ramallo, Virginia; Acuña-Alonzo, Victor; Adhikari, Kaustubh; Castillo, Lucía; Gomez-Valdés, Jorge; Everardo, Paola; De Avila, Francisco; Hünemeier, Tábita; Jaramillo, Claudia; Arias, Williams; Fuentes, Macarena; Gallo, Carla; Poletti, Giovani; Schuler-Faccini, Lavinia; Bortolini, Maria Cátira; Canizales-Quinteros, Samuel; Rothhammer, Francisco; Bedoya, Gabriel; Rosique, Javier; Ruiz-Linares, Andrés; González-José, Rolando

2017-01-01

The expression of facial asymmetries has been recurrently related with poverty and/or disadvantaged socioeconomic status. Departing from the developmental instability theory, previous approaches attempted to test the statistical relationship between the stress experienced by individuals grown in poor conditions and an increase in facial and corporal asymmetry. Here we aim to further evaluate such hypothesis on a large sample of admixed Latin Americans individuals by exploring if low socioeconomic status individuals tend to exhibit greater facial fluctuating asymmetry values. To do so, we implement Procrustes analysis of variance and Hierarchical Linear Modelling (HLM) to estimate potential associations between facial fluctuating asymmetry values and socioeconomic status. We report significant relationships between facial fluctuating asymmetry values and age, sex, and genetic ancestry, while socioeconomic status failed to exhibit any strong statistical relationship with facial asymmetry. These results are persistent after the effect of heterozygosity (a proxy for genetic ancestry) is controlled in the model. Our results indicate that, at least on the studied sample, there is no relationship between socioeconomic stress (as intended as low socioeconomic status) and facial asymmetries.

Mitigating the impact of hohlraum asymmetries in National Ignition Facility implosions using capsule shims

Energy Technology Data Exchange (ETDEWEB)

Clark, D. S.; Weber, C. R.; Smalyuk, V. A.; Robey, H. F.; Kritcher, A. L.; Milovich, J. L.; Salmonson, J. D. [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94550 (United States)

2016-07-15

Current indirect drive implosion experiments on the National Ignition Facility (NIF) [Moses et al., Phys. Plasmas 16, 041006 (2009)] are believed to be strongly impacted by long wavelength perturbations driven by asymmetries in the hohlraum x-ray flux. To address this perturbation source, active efforts are underway to develop modified hohlraum designs with reduced asymmetry imprint. An alternative strategy, however, is to modify the capsule design to be more resilient to a given amount of hohlraum asymmetry. In particular, the capsule may be deliberately misshaped, or “shimmed,” so as to counteract the expected asymmetries from the hohlraum. Here, the efficacy of capsule shimming to correct the asymmetries in two recent NIF implosion experiments is assessed using two-dimensional radiation hydrodynamics simulations. Despite the highly time-dependent character of the asymmetries and the high convergence ratios of these implosions, simulations suggest that shims could be highly effective at counteracting current asymmetries and result in factors of a few enhancements in neutron yields. For higher compression designs, the yield improvement could be even greater.

Load Asymmetry Observed During Orion Main Parachute Inflation

Science.gov (United States)

Morris, Aaron L.; Taylor, Thomas; Olson, Leah

2011-01-01

The Crew Exploration Vehicle Parachute Assembly System (CPAS) has flight tested the first two generations of the Orion parachute program. Three of the second generation tests instrumented the dispersion bridles of the Main parachute with a Tension Measuring System. The goal of this load measurement was to better understand load asymmetry during the inflation process of a cluster of Main parachutes. The CPAS Main parachutes exhibit inflations that are much less symmetric than current parachute literature and design guides would indicate. This paper will examine loads data gathered on three cluster tests, quantify the degree of asymmetry observed, and contrast the results with published design guides. Additionally, the measured loads data will be correlated with videos of the parachute inflation to make inferences about the shape of the parachute and the relative load asymmetry. The goal of this inquiry and test program is to open a dialogue regarding asymmetrical parachute inflation load factors.

Characteristics of toroidal energy deposition asymmetries in ASDEX

International Nuclear Information System (INIS)

Evans, T.E.; Neuhauser, J.; Leuterer, F.; Mueller, E.R.

1990-01-01

Large toroidal and poloidal asymmetries with characteristics which are sensitively dependent on q a , the vertical position of the plasma, and the type of additional heating are observed in the energy flow to the ASDEX divertor target plates. The largest asymmetries and total energy depositions are observed during lower hybrid wave injection experiments with approximately 50% of the input energy going to the combined divertor targets and shields. A maximum localized energy density loading of 10 MJ/m 2 is typical under these conditions. Measurements of the asymmetries are consistent with a model in which magnetic islands and ergodicity due to intrinsic magnetic perturbations dominate the energy transpot across the primary magnetic separatrix. The results emphasize the essential role of resonant magnetic perturbations in determining the performance of tokamaks and demonstrate that non-axisymmetric effects caused by small perturbations become increasingly important in determining the transport properties as the injected power is increased. (orig.)

Nanocrystal Bioassembly: Asymmetry, Proximity, and Enzymatic Manipulation

Energy Technology Data Exchange (ETDEWEB)

Claridge, Shelley A. [Univ. of California, Berkeley, CA (United States)

2008-05-01

Research at the interface between biomolecules and inorganic nanocrystals has resulted in a great number of new discoveries. In part this arises from the synergistic duality of the system: biomolecules may act as self-assembly agents for organizing inorganic nanocrystals into functional materials; alternatively, nanocrystals may act as microscopic or spectroscopic labels for elucidating the behavior of complex biomolecular systems. However, success in either of these functions relies heavily uponthe ability to control the conjugation and assembly processes.In the work presented here, we first design a branched DNA scaffold which allows hybridization of DNA-nanocrystal monoconjugates to form discrete assemblies. Importantly, the asymmetry of the branched scaffold allows the formation of asymmetric2assemblies of nanocrystals. In the context of a self-assembled device, this can be considered a step toward the ability to engineer functionally distinct inputs and outputs.Next we develop an anion-exchange high performance liquid chromatography purification method which allows large gold nanocrystals attached to single strands of very short DNA to be purified. When two such complementary conjugates are hybridized, the large nanocrystals are brought into close proximity, allowing their plasmon resonances to couple. Such plasmon-coupled constructs are of interest both as optical interconnects for nanoscale devices and as `plasmon ruler? biomolecular probes.We then present an enzymatic ligation strategy for creating multi-nanoparticle building blocks for self-assembly. In constructing a nanoscale device, such a strategy would allow pre-assembly and purification of components; these constructs can also act as multi-label probes of single-stranded DNA conformational dynamics. Finally we demonstrate a simple proof-of-concept of a nanoparticle analog of the polymerase chain reaction.

Quantification of extra-cerebral and cerebral hemoglobin concentrations during physical exercise using time-domain near infrared spectroscopy.

Science.gov (United States)

Auger, Héloïse; Bherer, Louis; Boucher, Étienne; Hoge, Richard; Lesage, Frédéric; Dehaes, Mathieu

2016-10-01

Fitness is known to have beneficial effects on brain anatomy and function. However, the understanding of mechanisms underlying immediate and long-term neurophysiological changes due to exercise is currently incomplete due to the lack of tools to investigate brain function during physical activity. In this study, we used time-domain near infrared spectroscopy (TD-NIRS) to quantify and discriminate extra-cerebral and cerebral hemoglobin concentrations and oxygen saturation ( SO 2 ) in young adults at rest and during incremental intensity exercise. In extra-cerebral tissue, an increase in deoxy-hemoglobin ( HbR ) and a decrease in SO 2 were observed while only cerebral HbR increased at high intensity exercise. Results in extra-cerebral tissue are consistent with thermoregulatory mechanisms to dissipate excess heat through skin blood flow, while cerebral changes are in agreement with cerebral blood flow ( CBF ) redistribution mechanisms to meet oxygen demand in activated regions during exercise. No significant difference was observed in oxy- ( HbO 2 ) and total hemoglobin ( HbT ). In addition HbO 2 , HbR and HbT increased with subject's peak power output (equivalent to the maximum oxygen volume consumption; VO 2 peak) supporting previous observations of increased total mass of red blood cells in trained individuals. Our results also revealed known gender differences with higher hemoglobin in men. Our approach in quantifying both extra-cerebral and cerebral absolute hemoglobin during exercise may help to better interpret past and future continuous-wave NIRS studies that are prone to extra-cerebral contamination and allow a better understanding of acute cerebral changes due to physical exercise.

Sodium transport through the cerebral sodium-glucose transporter exacerbates neuron damage during cerebral ischaemia.

Science.gov (United States)

Yamazaki, Yui; Harada, Shinichi; Wada, Tetsuyuki; Yoshida, Shigeru; Tokuyama, Shogo

2016-07-01

We recently demonstrated that the cerebral sodium-glucose transporter (SGLT) is involved in postischaemic hyperglycaemia-induced exacerbation of cerebral ischaemia. However, the associated SGLT-mediated mechanisms remain unclear. Thus, we examined the involvement of cerebral SGLT-induced excessive sodium ion influx in the development of cerebral ischaemic neuronal damage. [Na+]i was estimated according to sodium-binding benzofuran isophthalate fluorescence. In the in vitro study, primary cortical neurons were prepared from fetuses of ddY mice. Primary cortical neurons were cultured for 5 days before each treatment with reagents, and these survival rates were assessed using biochemical assays. In in vivo study, a mouse model of focal ischaemia was generated using middle cerebral artery occlusion (MCAO). In these experiments, treatment with high concentrations of glucose induced increment in [Na+]i, and this phenomenon was suppressed by the SGLT-specific inhibitor phlorizin. SGLT-specific sodium ion influx was induced using a-methyl-D-glucopyranoside (a-MG) treatments, which led to significant concentration-dependent declines in neuronal survival rates and exacerbated hydrogen peroxide-induced neuronal cell death. Moreover, phlorizin ameliorated these effects. Finally, intracerebroventricular administration of a-MG exacerbated the development of neuronal damage induced by MCAO, and these effects were ameliorated by the administration of phlorizin. Hence, excessive influx of sodium ions into neuronal cells through cerebral SGLT may exacerbate the development of cerebral ischaemic neuronal damage. © 2016 Royal Pharmaceutical Society.

Right-frontal cortical asymmetry predicts increased proneness to nostalgia.

Science.gov (United States)

Tullett, Alexa M; Wildschut, Tim; Sedikides, Constantine; Inzlicht, Michael

2015-08-01

Nostalgia is often triggered by feelings-such as sadness, loneliness, or meaninglessness-that are typically associated with withdrawal motivation. Here, we examined whether a trait tendency to experience withdrawal motivation is associated with nostalgia proneness. Past work indicates that baseline right-frontal cortical asymmetry is a neural correlate of withdrawal-related motivation. We therefore hypothesized that higher baseline levels of right-frontal asymmetry would predict increased proneness to nostalgia. We assessed participants' baseline levels of frontal cortical activity using EEG. Results supported the hypothesis and demonstrated that the association between relative right-frontal asymmetry and increased nostalgia remained significant when controlling for the Big Five personality traits. Overall, these findings indicate that individuals with a stronger dispositional tendency to experience withdrawal-related motivation are more prone to nostalgia. © 2015 Society for Psychophysiological Research.

Take your seats: Leftward asymmetry in classroom seating choice

Directory of Open Access Journals (Sweden)

Victoria Lynn Harms

2015-08-01

Full Text Available Despite an overall body symmetry, human behaviour is full of examples of asymmetry, from writing or gesturing to kissing and cradling. Prior research has revealed that theatre patrons show a bias towards sitting on the right side of a movie theatre. Two competing theories have attempted to explain this seating asymmetry: one posits that expectation of processing demand drives the bias; the other posits that basic motor asymmetries drive the bias. To test these theories we assessed the real-world classroom seating choices of university students using photographs. A bias for students to choose seats on the left side of the classroom was observed, in contrast to the right side bias observed in theatre seating studies. These results provide evidence in support of a processing-expectation bias.

Asymmetry in nonmesonic decay of polarized sup 5 subLAMBDA He hypernucleus

CERN Document Server

Ajimura, S; Ejiri, H; Hasegawa, T; Hashimoto, O; Ishikawa, M; Ikeda, K; Kim, Y; Kishimoto, T; Maeda, K; Manabe, K; Nagae, T; Nakano, T; Noumi, H; Okusu, A; Park, H; Sekimoto, M; Shibata, T; Shinkai, N; Takahashi, T; Tanaka, Y; Youn, M

2000-01-01

We have measured the asymmetric emission of protons and pions from the non mesonic decay of the polarized sup 5 subLAMBDA He produced by the (pi sup + , K sup +) reaction. The polarization was derived by the observed asymmetry of the mesonic decay pions for the first time. The asymmetry parameter of the non mesonic decay has been evaluated using the obtained polarization and the asymmetry of the decay protons. The positive asymmetry parameter contradicts theoretical prediction based on meson exchange model. The discrepancy can be attributed to insufficient knowledge of the weak LAMBDA N interaction, especially at short range, which may consistently explain the discrepancy seen in the partial decay rates of the non mesonic decay.

Vertical poloidal asymmetries of low-Z element radiation in the PDX tokamak

Energy Technology Data Exchange (ETDEWEB)

Brau, K.; Suckewer, S.; Wong, S.K.

1983-06-01

Vertical poloidal asymmetries of hydrogen isotopes and low-Z impurity radiation in the PDX tokamak may be caused by poloidally asymmetric sources of these elements at gas inlet valves, limiters or vacuum vessel walls, asymmetric magnetic field geometry in the region beyond the plasma boundary, or by ion curvature drifts. Low ionization states of carbon (C II- C IV) are more easily influenced by edge conditions than is CV. Vertical poloidal asymmetries of CV are correlated with the direction of the toroidal field. The magnitude of the asymmetry agrees with the predictions of a quasifluid neoclassical model. Experimental data and numerical simulations are presented to investigate different models of impurity poloidal asymmetries.

Vertical poloidal asymmetries of low-Z element radiation in the PDX tokamak

International Nuclear Information System (INIS)

Brau, K.; Suckewer, S.; Wong, S.K.

1983-06-01

Vertical poloidal asymmetries of hydrogen isotopes and low-Z impurity radiation in the PDX tokamak may be caused by poloidally asymmetric sources of these elements at gas inlet valves, limiters or vacuum vessel walls, asymmetric magnetic field geometry in the region beyond the plasma boundary, or by ion curvature drifts. Low ionization states of carbon (C II- C IV) are more easily influenced by edge conditions than is CV. Vertical poloidal asymmetries of CV are correlated with the direction of the toroidal field. The magnitude of the asymmetry agrees with the predictions of a quasifluid neoclassical model. Experimental data and numerical simulations are presented to investigate different models of impurity poloidal asymmetries

Body Posture Asymmetry Differences between Children with Mild Scoliosis and Children with Unilateral Cerebral Palsy

Directory of Open Access Journals (Sweden)

Małgorzata Domagalska-Szopa

2013-01-01

Full Text Available Patients with unilateral cerebral palsy (CP often have impaired movement coordination, reduced between-limb synchronization, and less weight bearing on the affected side, which can affect the maintenance of an upright weight-bearing position and gait. This study evaluated whether the different postural patterns of children with unilateral CP could be statistically recognized using cluster analysis. Forty-five outpatients with unilateral CP (mean age, 9 years and 5 months and 51 able-bodied children with mild scoliosis (mean age, 9 years and 2 months were included. One observer performed moiré topography (MT examinations using a CQ Electronic System (Poland device. A weight distribution analysis on the base of support (BOS between the body sides was performed simultaneously. A force plate dynamographic platform (PDM, ZEBRIS (Germany, with FootPrint software was used for these measurements. Cluster analysis revealed three groups: Cluster 1 (, 73.96%, Cluster 2 (, 8.33%, and Cluster 3 (, 17.71%. Based on the MT parameters (extracted using a data reduction technique, three typical asymmetrical postural patterns were described: (1 the postural pattern of children with mild scoliosis (SCOL, (2 the progravitational postural pattern (PGPP, and (3 the antigravitational pattern. Patterns two and three were identified in children with unilateral CP.

Normal range of facial asymmetry in spherical coordinates: a CBCT study

Energy Technology Data Exchange (ETDEWEB)

Yoon, Suk Ja [Dept. of Oral and Maxillofacial Radiology, School of Dentistry, Dental Science Research Institute, Chonnam National University, Gwangju (Korea, Republic of); Wang, Rui Feng [Research Laboratory Specialist Intermediate, Department of Biologic and Material Sciences, School of Dentistry, University of Michigan, Ann Arbor, MI (United States); Na, Hee Ja [Dept. ofDental Hygiene, Honam University, Gwangju (Korea, Republic of); Palomo, Juan Matin [Dept. of Orthodontics, School of Dental Medicine, Case Western Reserve University, Cleveland (United States)

2013-03-15

This study aimed to measure the bilateral differences of facial lines in spherical coordinates from faces within a normal range of asymmetry utilizing cone-beam computed tomography (CBCT). CBCT scans from 22 females with normal symmetric-looking faces (mean age 24 years and 8 months) were selected for the study. The average menton deviation was 1.01{+-}0.66 mm. The spherical coordinates, length, and midsagittal and coronal inclination angles of the ramal and mandibular lines were calculated from CBCT. The bilateral differences in the facial lines were determined. All of the study subjects had minimal bilateral differences of facial lines. The normal range of facial asymmetry of the ramal and mandibular lines was obtained in spherical coordinates. The normal range of facial asymmetry in the spherical coordinate system in this study should be useful as a reference for diagnosing facial asymmetry.

Prognostic implications of left ventricular asymmetry in patients with asymptomatic aortic valve stenosis

DEFF Research Database (Denmark)

Sigvardsen, Per Ejlstrup; Larsen, Linnea Hornbech; Carstensen, Helle Gervig

2018-01-01

Aims: Left ventricular (LV) regional hypertrophy in the form of LV asymmetry is a common finding in patients with aortic valve stenosis. The aim of this study was to test the hypothesis that LV asymmetry predicts future symptomatic status and indication for aortic valve replacement (AVR) in patie......Aims: Left ventricular (LV) regional hypertrophy in the form of LV asymmetry is a common finding in patients with aortic valve stenosis. The aim of this study was to test the hypothesis that LV asymmetry predicts future symptomatic status and indication for aortic valve replacement (AVR...... occurred in 46 patients (40%). Patients with LV asymmetry had more than 3 times the risk of AVR (hazard ratio: 3.16; 95% CI: 1.77-5.66; P future need of AVR (hazard ratio: 3.10; 95......% CI: 1.44-6.65; P = 0.004), independent of LV geometry, jet velocity, valvular calcification, and pro-BNP. Conclusions: LV asymmetry is an independent predictor of future need for AVR in patients with asymptomatic aortic valve stenosis. It has incremental prognostic value to LV geometry and may...

In-flight observations of low-mode ρR asymmetries in NIF implosions

Energy Technology Data Exchange (ETDEWEB)

Zylstra, A. B., E-mail: zylstra@mit.edu; Frenje, J. A.; Séguin, F. H.; Rosenberg, M. J.; Rinderknecht, H. G.; Gatu Johnson, M.; Li, C. K.; Manuel, M. J.-E.; Petrasso, R. D.; Sinenian, N.; Sio, H. W. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Rygg, J. R.; Kritcher, A.; Hicks, D. G.; Friedrich, S.; Bionta, R.; Meezan, N. B.; Atherton, J.; Barrios, M.; Bell, P. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); and others

2015-05-15

Charged-particle spectroscopy is used to assess implosion symmetry in ignition-scale indirect-drive implosions for the first time. Surrogate D{sup 3}He gas-filled implosions at the National Ignition Facility produce energetic protons via D+{sup 3}He fusion that are used to measure the implosion areal density (ρR) at the shock-bang time. By using protons produced several hundred ps before the main compression bang, the implosion is diagnosed in-flight at a convergence ratio of 3–5 just prior to peak velocity. This isolates acceleration-phase asymmetry growth. For many surrogate implosions, proton spectrometers placed at the north pole and equator reveal significant asymmetries with amplitudes routinely ≳10%, which are interpreted as ℓ=2 Legendre modes. With significant expected growth by stagnation, it is likely that these asymmetries would degrade the final implosion performance. X-ray self-emission images at stagnation show asymmetries that are positively correlated with the observed in-flight asymmetries and comparable in magnitude, contradicting growth models; this suggests that the hot-spot shape does not reflect the stagnated shell shape or that significant residual kinetic energy exists at stagnation. More prolate implosions are observed when the laser drive is sustained (“no-coast”), implying a significant time-dependent asymmetry in peak drive.

Reversal of severe SPECT asymmetry after venous extra-intracranial high flow bypass in a patient submitted to therapeutic internal carotid occlusion: case report Reversão de importante assimetria ao SPECT após bypass venoso de alto fluxo extra-intracraniano em paciente submetido a oclusão terapêutica da carótida interna: relato de caso

Directory of Open Access Journals (Sweden)

Jorge Marcondes

2001-09-01

Full Text Available Therapeutic occlusion of the internal carotid artery is the main option for the treatment of the symptomatic intracavernous internal carotid artery aneurysms, but the issue of the best way of doing the balloon test occlusion (BTO regarding prediction of future ischemic events remains debatable. Single photon emission computerized tomography (SPECT has been offered as one of the best option of monitoring regional cerebral blood flow (rCBF during the BTO, where severe asymmetry is predictive of delayed ischemia. We describe a case of important SPECT asymmetry during BTO clinically negative and its complete reversal with carotid occlusion after extra-intracranial bypass with high flow safenous vein bypass between the cervical carotid artery and the middle cerebral artery.Oclusão terapêutica carotídea ainda é a principal escolha para o tratamento dos aneurismas sintomáticos da artéria carótida interna ao nível do seio cavernoso.Existem controvérsias em relação à obtenção de testes com maior valor preditivo em relação à complicações isquêmicas futuras durante a realização do teste de oclusão carotídeo por balão. A tomografia computorizada de emissão de fóton único (SPECT tem sido defendida como uma opção para a melhor avaliação do fluxo sanguíneo regional cerebral, onde evidente assimetria é indicativa de isquemia tardia. Descrevemos um caso de importante assimetria ao SPECT durante o teste clinicamente negativo e sua reversão completa após anastomose extra-intracraniana com interposição de veia safena magna (alto fluxo entre a artéria carótida cervical e a artéria cerebral média.

The gluon Sivers asymmetry measurements at COMPASS

CERN Document Server

Szabelski, Adam

2018-01-01

The Sivers function describes the correlation between the transverse spin of a nucleon and the transverse motion of its partons. As such, a nonzero Sivers effect for gluons could be a signature of their nonzero orbital angular momentum inside the nucleon. COMPASS has collected data of semi-inclusive deep inelastic scattering by impinging 160 GeV/$c$ muons on transversely polarised proton and deuteron targets. The gluon Sivers asymmetry is extracted from a high-$p_T$ hadron pair sample with the use of monte carlo simulations and the a neural network approach. The results of a similar analysis for a Collins-like asymmetry for gluons will also be given.

The gluon Sivers asymmetry measurements at COMPASS

CERN Document Server

Szabelski, Adam

2017-01-01

The Sivers function describes the correlation between the transverse spin of a nucleon and the transverse motion of its partons. As such, a nonzero Sivers effect for gluons could be a signature of their nonzero orbital angular momentum inside the nucleon. COMPASS has collected data of semi-inclusive deep inelastic scattering by impinging 160 GeV/$c$ muons on transversely polarised proton and deuteron targets. The gluon Sivers asymmetry is extracted from a high-$p_T$ hadron pair sample with the use of monte carlo simulations and the a neural network approach. The results of a similar analysis for a Collins-like asymmetry for gluons will also be given.

Therapeutic interventions in cerebral palsy.

Science.gov (United States)

Patel, Dilip R

2005-11-01

Various therapeutic interventions have been used in the management of children with cerebral palsy. Traditional physiotherapy and occupational therapy are widely used interventions and have been shown to be of benefit in the treatment of cerebral palsy. Evidence in support of the effectiveness of the neurodevelopmental treatment is equivocal at best. There is evidence to support the use and effectiveness of neuromuscular electrical stimulation in children with cerebral palsy. The effectiveness of many other interventions used in the treatment of cerebral palsy has not been clearly established based on well-controlled trials. These include: sensory integration, body-weight support treadmill training, conductive education, constraint-induced therapy, hyperbaric oxygen therapy, and the Vojta method. This article provides an overview of salient aspects of popular interventions used in the management of children with cerebral palsy.

Nanomedicine in cerebral palsy

Directory of Open Access Journals (Sweden)

Balakrishnan B

2013-11-01

Full Text Available Bindu Balakrishnan,1 Elizabeth Nance,1 Michael V Johnston,2 Rangaramanujam Kannan,3 Sujatha Kannan1 1Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University; Baltimore, MD, USA; 2Department of Neurology and Pediatrics, Kennedy Krieger Institute, Baltimore, MD, USA; 3Department of Ophthalmology, Center for Nanomedicine, Johns Hopkins University, Baltimore, MD, USA Abstract: Cerebral palsy is a chronic childhood disorder that can have diverse etiologies. Injury to the developing brain that occurs either in utero or soon after birth can result in the motor, sensory, and cognitive deficits seen in cerebral palsy. Although the etiologies for cerebral palsy are variable, neuroinflammation plays a key role in the pathophysiology of the brain injury irrespective of the etiology. Currently, there is no effective cure for cerebral palsy. Nanomedicine offers a new frontier in the development of therapies for prevention and treatment of brain injury resulting in cerebral palsy. Nanomaterials such as dendrimers provide opportunities for the targeted delivery of multiple drugs that can mitigate several pathways involved in injury and can be delivered specifically to the cells that are responsible for neuroinflammation and injury. These materials also offer the opportunity to deliver agents that would promote repair and regeneration in the brain, resulting not only in attenuation of injury, but also enabling normal growth. In this review, the current advances in nanotechnology for treatment of brain injury are discussed with specific relevance to cerebral palsy. Future directions that would facilitate clinical translation in neonates and children are also addressed. Keywords: dendrimer, cerebral palsy, neuroinflammation, nanoparticle, neonatal brain injury, G4OH-PAMAM

Measurement of CP asymmetry in D0→K−K+ decays

Directory of Open Access Journals (Sweden)

R. Aaij

2017-04-01

These are the most precise measurements from a single experiment. The result for ACP(K−K+ is the most precise determination of a time-integrated CP asymmetry in the charm sector to date, and neither measurement shows evidence of CP asymmetry.

microRNA function in left-right neuronal asymmetry: perspectives from C. elegans

OpenAIRE

Alqadah, Amel; Hsieh, Yi-Wen; Chuang, Chiou-Fen

2013-01-01

Left–right asymmetry in anatomical structures and functions of the nervous system is present throughout the animal kingdom. For example, language centers are localized in the left side of the human brain, while spatial recognition functions are found in the right hemisphere in the majority of the population. Disruption of asymmetry in the nervous system is correlated with neurological disorders. Although anatomical and functional asymmetries are observed in mammalian nervous systems, it has b...

Cerebral oxygen metabolism and cerebral blood flow in man during light sleep (stage 2)

DEFF Research Database (Denmark)

Madsen, P L; Schmidt, J F; Holm, S

1991-01-01

We measured cerebral blood flow (CBF) and cerebral metabolic rate of oxygen (CMRO2) during light sleep (stage 2) in 8 young healthy volunteers using the Kety-Schmidt technique with 133Xe as the inert gas. Measurements were performed during wakefulness and light sleep as verified by standard...... polysomnography. Unlike our previous study in man showing a highly significant 25% decrease in CMRO2 during deep sleep (stage 3-4) we found a modest but statistically significant decrease of 5% in CMRO2 during stage 2 sleep. Deep and light sleep are both characterized by an almost complete lack of mental activity....... They differ in respect of arousal threshold as a stronger stimulus is required to awaken a subject from deep sleep as compared to light sleep. Our results suggest that during non-rapid eye movement sleep cerebral metabolism and thereby cerebral synaptic activity is correlated to cerebral readiness rather than...

Cerebral fat embolism

International Nuclear Information System (INIS)

Sakamoto, Toshihisa; Sawada, Yusuke; Yukioka, Tetsuo; Nishide, Kazuyuki; Yoshioka, Toshiharu

1982-01-01

A case of cerebral fat embolism is reported. A 18-year-old patient with multiple bone fractures was in semiconma immediately after an injury. Brain CT showed no brain swelling or intracranial hematoma. Hypoxemia and alcoholemia were noted on admission, which returned to normal without improvement of consciousness level. In addition, respiratory symptoms with positive radiographic changes, tachycardia, pyrexia, sudden drop in hemoglobin level, and sudden thrombocytopenia developed. These symptoms were compatible with Gurd's criteria of systemic fat embolism. Eight days after injury, multiple low density areas appeared on CT and disappeared within the subsequent two weeks, and subdural effusion with cerebral atrophy developed. These CT findings were not considered due to cerebral trauma. Diagnosis of cerebral fat embolism was made. The subdural effusion was drained. Neurologic and pulmonary recoveries took place slowly and one month following the injury the patient became alert and exhibited fully coordinated limb movement. The CT scans of the present case well corresponded with hitherto reported pathological findings. Petechiae in the white matter must have developed on the day of injury, which could not be detected by CT examination. It is suggested that some petechial regions fused to purpuras and then gradually resolved when they were detected as multiple low density areas on CT. CT in the purpuras phase would have shown these lesions as high density areas. These lesions must have healed with formation of tiny scars and blood pigment which were demonstrated as the disappearance of multiple low density areas by CT examination. Cerebral atrophy and subsequent subdural effusion developed as a result of demyelination. The patient took the typical clinical course of cerebral fat embolism and serial CT scans served for its assessment. (author)

Quantifying Normal Craniofacial Form and Baseline Craniofacial Asymmetry in the Pediatric Population.

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Cho, Min-Jeong; Hallac, Rami R; Ramesh, Jananie; Seaward, James R; Hermann, Nuno V; Darvann, Tron A; Lipira, Angelo; Kane, Alex A

2018-03-01

Restoring craniofacial symmetry is an important objective in the treatment of many craniofacial conditions. Normal form has been measured using anthropometry, cephalometry, and photography, yet all of these modalities have drawbacks. In this study, the authors define normal pediatric craniofacial form and craniofacial asymmetry using stereophotogrammetric images, which capture a densely sampled set of points on the form. After institutional review board approval, normal, healthy children (n = 533) with no known craniofacial abnormalities were recruited at well-child visits to undergo full head stereophotogrammetric imaging. The children's ages ranged from 0 to 18 years. A symmetric three-dimensional template was registered and scaled to each individual scan using 25 manually placed landmarks. The template was deformed to each subject's three-dimensional scan using a thin-plate spline algorithm and closest point matching. Age-based normal facial models were derived. Mean facial asymmetry and statistical characteristics of the population were calculated. The mean head asymmetry across all pediatric subjects was 1.5 ± 0.5 mm (range, 0.46 to 4.78 mm), and the mean facial asymmetry was 1.2 ± 0.6 mm (range, 0.4 to 5.4 mm). There were no significant differences in the mean head or facial asymmetry with age, sex, or race. Understanding the "normal" form and baseline distribution of asymmetry is an important anthropomorphic foundation. The authors present a method to quantify normal craniofacial form and baseline asymmetry in a large pediatric sample. The authors found that the normal pediatric craniofacial form is asymmetric, and does not change in magnitude with age, sex, or race.

Measurement and genetics of human subcortical and hippocampal asymmetries in large datasets.

Science.gov (United States)

Guadalupe, Tulio; Zwiers, Marcel P; Teumer, Alexander; Wittfeld, Katharina; Vasquez, Alejandro Arias; Hoogman, Martine; Hagoort, Peter; Fernandez, Guillen; Buitelaar, Jan; Hegenscheid, Katrin; Völzke, Henry; Franke, Barbara; Fisher, Simon E; Grabe, Hans J; Francks, Clyde

2014-07-01

Functional and anatomical asymmetries are prevalent features of the human brain, linked to gender, handedness, and cognition. However, little is known about the neurodevelopmental processes involved. In zebrafish, asymmetries arise in the diencephalon before extending within the central nervous system. We aimed to identify genes involved in the development of subtle, left-right volumetric asymmetries of human subcortical structures using large datasets. We first tested the feasibility of measuring left-right volume differences in such large-scale samples, as assessed by two automated methods of subcortical segmentation (FSL|FIRST and FreeSurfer), using data from 235 subjects who had undergone MRI twice. We tested the agreement between the first and second scan, and the agreement between the segmentation methods, for measures of bilateral volumes of six subcortical structures and the hippocampus, and their volumetric asymmetries. We also tested whether there were biases introduced by left-right differences in the regional atlases used by the methods, by analyzing left-right flipped images. While many bilateral volumes were measured well (scan-rescan r = 0.6-0.8), most asymmetries, with the exception of the caudate nucleus, showed lower repeatabilites. We meta-analyzed genome-wide association scan results for caudate nucleus asymmetry in a combined sample of 3,028 adult subjects but did not detect associations at genome-wide significance (P left-right patterning of the viscera. Our results provide important information for researchers who are currently aiming to carry out large-scale genome-wide studies of subcortical and hippocampal volumes, and their asymmetries. Copyright © 2013 Wiley Periodicals, Inc.

The cos2φ azimuthal asymmetry of unpolarized dilepton production at the Z pole

International Nuclear Information System (INIS)

Lu Zhun; Schmidt, Ivan

2011-01-01

We calculate the Boer-Mulders effect contribution to the cos2φ azimuthal asymmetry of unpolarized dilepton production near the Z-pole. Based on the tree-level expression in the transverse momentum dependent factorization framework, we show that the corresponding asymmetry near the Z-pole is negative, which is opposite to the asymmetry in the low Q 2 region, dominated by the production via a virtual photon. We calculate the asymmetry generated by the Boer-Mulders effect near the Z-pole at the Relativistic Heavy Ion Collider (RHIC), with √(s)=500 GeV. We find that the magnitude of the asymmetry is several percent, and therefore it is measurable. The experimental confirmation of this sign change of the asymmetry from the low Q 2 region to the Z-pole provides direct evidence of the chiral-odd structure of quarks inside an unpolarized nucleon.

Detraditionalisation, gender and alternative and complementary medicines.

Science.gov (United States)

Sointu, Eeva

2011-03-01

This article is premised on the importance of locating the appeal and meaning of alternative and complementary medicines in the context of gendered identities. I argue that the discourse of wellbeing--captured in many alternative and complementary health practices--is congruent with culturally prevalent ideals of self-fulfilling, authentic, unique and self-responsible subjectivity. The discourse of wellbeing places the self at the centre, thus providing a contrast with traditional ideas of other-directed and caring femininity. As such, involvement in alternative and complementary medicines is entwined with a negotiation of shifting femininities in detraditionalising societies. Simultaneously, many alternative and complementary health practices readily tap into and reproduce traditional representations of caring femininity. It is through an emphasis on emotional honesty and intimacy that the discourse of wellbeing also captures a challenge to traditional ideas of masculinity. Expectations and experiences relating to gender add a further level of complexity to the meaningfulness and therapeutic value of alternative and complementary medicines and underlie the gender difference in the utilisation of holistic health practices. I draw on data from a qualitative study with 44, primarily white, middle-class users and practitioners of varied alternative and complementary medicines in the UK. © 2010 The Author. Sociology of Health & Illness © 2010 Foundation for the Sociology of Health & Illness/Blackwell Publishing Ltd.

Theoretical morphology and development of flight feather vane asymmetry with experimental tests in parrots.

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Feo, Teresa J; Prum, Richard O

2014-06-01

Asymmetry in flight feather vane width is a major functional innovation associated with the evolution of flight in the ancestors of birds. However, the developmental and morphological basis of feather shape is not simple, and the developmental processes involved in vane width asymmetry are poorly understood. We present a theoretical model of feather morphology and development that describes the possible ways to modify feather development and produce vane asymmetry. Our model finds that the theoretical morphospace of feather shape is redundant, and that many different combinations of parameters could be responsible for vane asymmetry in a given feather. Next, we empirically measured morphological and developmental model parameters in asymmetric and symmetric feathers from two species of parrots to identify which combinations of parameters create vane asymmetry in real feathers. We found that both longer barbs, and larger barb angles in the relatively wider trailing vane drove asymmetry in tail feathers. Developmentally, longer barbs were the result of an offset of the radial position of the new barb locus, whereas larger barb angles were produced by differential expansion of barbs as the feather unfurls from the tubular feather germ. In contrast, the helical angle of barb ridge development did not contribute to vane asymmetry and could be indicative of a constraint. This research provides the first comprehensive description of both the morphological and developmental modifications responsible for vane asymmetry within real feathers, and identifies key steps that must have occurred during the evolution of vane asymmetry. © 2014 Wiley Periodicals, Inc.

Study of the s - s bar asymmetry in the proton

Science.gov (United States)

Goharipour, Muhammad

2018-05-01

The study of s - s bar asymmetry is essential to better understand of the structure of nucleon and also the perturbative and nonperturbative mechanisms for sea quark generation. Actually, the nature and dynamical origins of this asymmetry have always been an interesting subject to research both experimentally and theoretically. One of the most powerful models can lead to s - s bar asymmetry is the meson-baryon model (MBM). In this work, using a simplified configuration of this model suggested by Pumplin, we calculate the s - s bar asymmetry for different values of cutoff parameter Λ, to study the dependence of model to this parameter and also to estimate the theoretical uncertainty imposed on the results due to its uncertainty. Then, we study the evolution of distributions obtained both at next-to-leading order (NLO) and next-to-next-to-leading order (NNLO) using different evolution schemes. It is shown that the evolution of the intrinsic quark distributions from a low initial scale, as suggested by Chang and Pang, is not a good choice at NNLO using variable flavor number scheme (VFNS).

Comparing Neutron Star Kicks to Supernova Remnant Asymmetries

Energy Technology Data Exchange (ETDEWEB)

Holland-Ashford, Tyler; Lopez, Laura A. [The Ohio State University Department of Astronomy, 140 W 18th Avenue, Columbus, OH 43201 (United States); Auchettl, Katie [The Ohio State University Center for Cosmology and Astro-particle Physics, 191 West Woodruff Avenue, Columbus, OH 43210 (United States); Temim, Tea [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Ramirez-Ruiz, Enrico, E-mail: holland-ashford.1@osu.edu [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States)

2017-07-20

Supernova explosions are inherently asymmetric and can accelerate new-born neutron stars (NSs) to hundreds of km s{sup −1}. Two prevailing theories to explain NS kicks are ejecta asymmetries (e.g., conservation of momentum between NS and ejecta) and anisotropic neutrino emission. Observations of supernova remnants (SNRs) can give us insights into the mechanism that generates these NS kicks. In this paper, we investigate the relationship between NS kick velocities and the X-ray morphologies of 18 SNRs observed with the Chandra X-ray Observatory and the Röntgen Satellite ( ROSAT ). We measure SNR asymmetries using the power-ratio method (a multipole expansion technique), focusing on the dipole, quadrupole, and octupole power ratios. Our results show no correlation between the magnitude of the power ratios and NS kick velocities, but we find that for Cas A and G292.0+1.8, whose emission traces the ejecta distribution, their NSs are preferentially moving opposite to the bulk of the X-ray emission. In addition, we find a similar result for PKS 1209–51, CTB 109, and Puppis A; however, their emission is dominated by circumstellar/interstellar material, so their asymmetries may not reflect their ejecta distributions. Our results are consistent with the theory that NS kicks are a consequence of ejecta asymmetries as opposed to anisotropic neutrino emission. In the future, additional observations to measure NS proper motions within ejecta-dominated SNRs are necessary to robustly constrain the NS kick mechanism.

Asymmetry and the shift of the Compton profile

International Nuclear Information System (INIS)

Chatterjee, B.K.; Roy, S.C.; Suric, T.; LaJohn, L.A.; Pratt, R.H.

2007-01-01

We show that the conventionally defined asymmetry of the Compton profile (CP) is, to a large extent, simply a shift of CP. Compton scattering is widely used in studying the electron momentum distribution (EMD) of complex systems. Extraction of information about the EMD is based on an impulse approximation (IA) description of the process. In IA the scattering from bound electrons is described as scattering from the EMD of free electrons. Most often the angular and energy distributions of scattered photons (doubly differential cross sections (DDCS)) is measured and presented in terms of CP, which is just the DDCS normalized by a kinematical factor. The deviations of measured CP from the IA results are conventionally described as an asymmetry of CP about the IA peak position. IA predicts CP to be symmetric. We have examined the discrepancy between IA predictions (and the corresponding relativistic version of IA, RIA) and more rigorous approaches (A 2 and S-matrix), using independent particle approximations for the description of the bound state of electrons. In the nonrelativistic region (in which many measurements of CP are performed) we find that the conventional asymmetry can largely be understood as the shift of the peak position. The true asymmetry with respect to the shifted peak position is in fact much smaller. RIA has similar properties to IA, except that for atoms with high nuclear charge the p → .A → interaction may modify the shift and limit the utility of description as a shift

Integrative Medicine and Complementary and Alternative Therapies

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... complementary therapies with your healthcare team: Are there complementary therapies that you would recommend? What research is available about this therapy’s safety and effectiveness? What are the benefits and risks of this ...

African Journal of Traditional, Complementary and Alternative ...

African Journals Online (AJOL)

African Journal of Traditional, Complementary and Alternative Medicines: Advanced Search. Journal Home > African Journal of Traditional, Complementary and Alternative Medicines: Advanced Search. Log in or Register to get access to full text downloads.

Lambda production and its asymmetry

International Nuclear Information System (INIS)

Tatsumi, Daisuke

1995-01-01

Differential cross section and asymmetry for Λ 0 , Λ-bar 0 production have been measured in e + e - annihilation at 58 GeV in the scaled momentum Xp range from 0.0 to 0.25. Using 241 pb -1 of data collected after VENUS detector upgrade in 1991. (author)

Imaging findings and cerebral perfusion in arterial ischemic stroke due to transient cerebral arteriopathy in children; Achados de imagem e perfusao arterial cerebral em acidente vascular cerebral isquemico devido a arteriopatia transitoria em crianca

Energy Technology Data Exchange (ETDEWEB)

Barbosa Junior, Alcino Alves, E-mail: alcinojr@uol.com.br [Departamento de Diagnostico por Imagem, Hospital Israelita Albert Einstein - HIAE, Sao Paulo, SP (Brazil); Ellovitch, Saada Resende de Souza [Neuropediatria, Hospital Israelita Albert Einstein - HIAE, Sao Paulo, SP (Brazil); Pincerato, Rita de Cassia Maciel [Hospital Samaritano, Sao Paulo, SP (Brazil)

2012-04-15

We report the case of a 4-year-old female child who developed an arterial ischemic stroke in the left middle cerebral artery territory, due to a proximal stenosis of the supraclinoid internal carotid artery, most probably related to transient cerebral arteriopathy of childhood. Computed tomography scan, magnetic resonance imaging, perfusion magnetic resonance and magnetic resonance angiography are presented, as well as follow-up by magnetic resonance and magnetic resonance angiography exams. Changes in cerebral perfusion and diffusion-perfusion mismatch call attention. As far as we know, this is the first report of magnetic resonance perfusion findings in transient cerebral arteriopathy. (author)

Sterile neutrinos, lepton asymmetries, primordial elements: How much of each?

International Nuclear Information System (INIS)

Chu Yizen; Cirelli, Marco

2006-01-01

We investigate quantitatively the extent to which having a primordial leptonic asymmetry (n ν ≠n ν ) relaxes the bounds on light sterile neutrinos imposed by BBN and LSS. We adopt a few assumptions that allow us to solve the neutrino evolution equations over a broad range of mixing parameters and asymmetries. For the general cases of sterile mixing with the electron or muon neutrino, we identify the regions that can be reopened. For the particular case of a LSND-like sterile neutrino, soon to be rejected or confirmed by MiniBooNE, we find that an asymmetry of the order of 10 -4 is needed to lift the conflicts with cosmology

CP asymmetries in the supersymmetric trilepton signal at the LHC

International Nuclear Information System (INIS)

Bornhauser, S.; Drees, M.; Dreiner, H.; Eboli, O.J.P.; Kim, J.S.; Kittel, O.

2012-01-01

In the CP-violating Minimal Supersymmetric Standard Model, we study the production of a neutralino-chargino pair at the LHC. For their decays into three leptons, we analyze CP asymmetries which are sensitive to the CP phases of the neutralino and chargino sector. We present analytical formulas for the entire production and decay process, and identify the CP-violating contributions in the spin correlation terms. This allows us to define the optimal CP asymmetries. We present a detailed numerical analysis of the cross sections, branching ratios, and the CP observables. For light neutralinos, charginos, and squarks, the asymmetries can reach several 10%. We estimate the discovery potential for the LHC to observe CP violation in the trilepton channel. (orig.)

Prediction of cerebral ischemia due to cerebral vasospasm in SAH using SPECT and sup 123 I-IMP with acetazolamide test

Energy Technology Data Exchange (ETDEWEB)

Nakagawara, Jyoji; Wada, Keiji; Takeda, Rihei; Usami, Takashi; Hashimoto, Ikuo; Shimazaki, Mitsuteru; Tanaka, Chiharu; Nakamura, Jun-ichi (Nakamura Memorial Hospital, Sapporo (Japan)); Suematsu, Katsumi

1989-11-01

To investigate the possibility of predicting cerebral ischemia due to cerebral vasospasm in subarachnoid hemorrhage (SAH), serial evaluation of the cerebral vasodilatory capacity by the acetazolamide test was conducted, using single photon emission computed tomography (SPECT) and N-isopropyl {sup 123}I-p-iodoamphetamine (IMP), in 17 patients with cerebral vasospasm following early surgery for ruptured aneurysms. The degree of vasospasm measured on the angiograms was classified into the following three types; mild degree (25%>stenosis), moderate degree (25{approx}50% stenosis), and severe degree(50%cerebral vasodilatory capacity was preserved at the normal level during the period of vasospasm. In eight patients with asymptomatic vasospasm (moderate degree), a transient limitation of cerebral vasodiratory capacity was observed between the 6th and 16th day after a rupture of the cerebral aneurysm. In five patients with symptomatic vasospasm resulting in reversible ischemia, a marked limitation of cerebral vasodilatory capacity was noted between the 7th and 15th day, and a delayed recovery of cerebral vasodilatory capacity was observed. This reversibility of cerebral vasodilatory capacity in patients with cerebral vasospasm suggests that a local decrease of purfusion pressure due to cerebral vasospasm causes compensatory vasodilation of intraparenchymal arteries and the vasodilatory reaction to acetazolamide was limited until the release of the cerebral vasospasm. Therefore, assessment of cerebral vasodilatory capacity in SAH by the acetazolamide test might predict the appearance and continuation of potential ischemia of the brain caused by the reduction of perfusion pressure due to cerebral vasospasm. (J.P.N.).

Signs of Asymmetry in Exploding Stars

Science.gov (United States)

Hensley, Kerry

2018-03-01

Supernova explosions enrich the interstellar medium and can even briefly outshine their host galaxies. However, the mechanism behind these massive explosions still isnt fully understood. Could probing the asymmetry of supernova remnants help us better understand what drives these explosions?Hubble image of the remnant of supernova 1987A, one of the first remnants discovered to be asymmetrical. [ESA/Hubble, NASA]Stellar Send-OffsHigh-mass stars end their lives spectacularly. Each supernova explosion churns the interstellar medium and unleashes high-energy radiation and swarms of neutrinos. Supernovae also suffuse the surrounding interstellar medium with heavy elements that are incorporated into later generations of stars and the planets that form around them.The bubbles of expanding gas these explosions leave behind often appear roughly spherical, but mounting evidence suggests that many supernova remnants are asymmetrical. While asymmetry in supernova remnants can arise when the expanding material plows into the non-uniform interstellar medium, it can also be an intrinsic feature of the explosion itself.Simulation results clockwise from top left: Mass density, calcium mass fraction, oxygen mass fraction, nickel-56 mass fraction. Click to enlarge. [Adapted from Wollaeger et al. 2017]Coding ExplosionsThe presence or absence of asymmetry in a supernova remnant can hold clues as to what drove the explosion. But how can we best observe asymmetry in a supernova remnant? Modeling lets us explore different observational approaches.A team of scientists led by Ryan T. Wollaeger (Los Alamos National Laboratory) used radiative transfer and radiative hydrodynamics simulations to model the explosion of a core-collapse supernova. Wollaeger and collaborators introduced asymmetry into the explosion by creating a single-lobed, fast-moving outflow along one axis.Their simulations showed that while some chemical elements lingered near the origin of the explosion or were distributed

Soft tissue nasal asymmetry as an indicator of orofacial cleft predisposition

DEFF Research Database (Denmark)

Zhang, Charles; Miller, Steven F; Roosenboom, Jasmien

2018-01-01

The biological relatives of offspring with nonsyndromic orofacial clefts have been shown to exhibit distinctive facial features, including excess asymmetry, which are hypothesized to indicate the presence of genetic risk factors. The significance of excess soft tissue nasal asymmetry in at-risk r...

Morphologic evaluation and classification of facial asymmetry using 3-dimensional computed tomography.

Science.gov (United States)

Baek, Chaehwan; Paeng, Jun-Young; Lee, Janice S; Hong, Jongrak

2012-05-01

A systematic classification is needed for the diagnosis and surgical treatment of facial asymmetry. The purposes of this study were to analyze the skeletal structures of patients with facial asymmetry and to objectively classify these patients into groups according to these structural characteristics. Patients with facial asymmetry and recent computed tomographic images from 2005 through 2009 were included in this study, which was approved by the institutional review board. Linear measurements, angles, and reference planes on 3-dimensional computed tomograms were obtained, including maxillary (upper midline deviation, maxilla canting, and arch form discrepancy) and mandibular (menton deviation, gonion to midsagittal plane, ramus height, and frontal ramus inclination) measurements. All measurements were analyzed using paired t tests with Bonferroni correction followed by K-means cluster analysis using SPSS 13.0 to determine an objective classification of facial asymmetry in the enrolled patients. Kruskal-Wallis test was performed to verify differences among clustered groups. P < .05 was considered statistically significant. Forty-three patients (18 male, 25 female) were included in the study. They were classified into 4 groups based on cluster analysis. Their mean age was 24.3 ± 4.4 years. Group 1 included subjects (44% of patients) with asymmetry caused by a shift or lateralization of the mandibular body. Group 2 included subjects (39%) with a significant difference between the left and right ramus height with menton deviation to the short side. Group 3 included subjects (12%) with atypical asymmetry, including deviation of the menton to the short side, prominence of the angle/gonion on the larger side, and reverse maxillary canting. Group 4 included subjects (5%) with severe maxillary canting, ramus height differences, and menton deviation to the short side. In this study, patients with asymmetry were classified into 4 statistically distinct groups according to

Monitoring of cerebral haemodynamics in newborn infants

DEFF Research Database (Denmark)

Liem, K Djien; Greisen, Gorm

2010-01-01

The most important cerebrovascular injuries in newborn infants, particularly in preterm infants, are cerebral haemorrhage and ischemic injury. The typical cerebral vascular anatomy and the disturbance of cerebral haemodynamics play important roles in the pathophysiology. The term 'cerebral haemod...

[A case of severe asthma exacerbation complicated with cerebral edema and diffuse multiple cerebral micro-bleeds].

Science.gov (United States)

Ohkura, Noriyuki; Fujimura, Masaki; Sakai, Asao; Fujita, Kentaro; Katayama, Nobuyuki

2009-08-01

A 36-year-old woman was admitted to the Intensive Care Unit for the treatment of severe asthma exacerbation. Her condition of asthma improved with systemic glucocorticosteroids, inhaled beta2-agonist, intravenous theophylline and inhaled anesthesia (isoflurane) under mechanical ventilation. Her consciousness was disturbed even after terminating isoflurane. Brain CT and MRI scan showed cerebral edema and diffuse multiple cerebral micro-bleeds. Glyceol, a hyperosmotic diuretic solution consisting of 10% glycerol and 5% fructose in saline, was administered to decrease cerebral edema. Her consciousness disturbance gradually recovered. Cerebral edema and hemorrhage improved. On the 69th hospital day, she was discharged from hospital without sequelae. This case is a rare one in which severe asthma exacerbation was complicated with cerebral edema and diffuse multiple cerebral hemorrhage. Inhaled anesthesia for asthma exacerbation should be used carefully to avoid delay of diagnosis of central nervous system complications.

Recovery of cerebral blood flow in unilateral chronic subdural hematoma. The correlation with cerebral re-expansion in elders

International Nuclear Information System (INIS)

Nemoto, Akio

2003-01-01

CT and SPECT were used to investigate the relationship between cerebral re-expansion and changes in cerebral blood flow underneath hematoma in elderly patients after surgery for chronic unilateral subdural hematoma. I studied 22 patients with mild hematoma, aged 43 to 82 years (mean 67 years). The patients were placed in either Group A (under 70 years) or Group B (70 years or over) to observe postoperative changes. CT and SPECT examinations were conducted before surgery and 1, 7 and 30 days after surgery, 4 times in total. Cerebral re-expansion was represented by the re-expansion rate (PER) comparing the pre- and postoperative thickness of the maximal hematoma in CT images. The rate of cerebral re-expansion was slowed in Group B (p<0.01). Cerebral re-expansion was characterized by biphasic, rapid or gradual re-expansion on postoperative day 1 with a significant difference between groups (p<0.01). Before surgery, cerebral blood flow on the affected side correlated with age (p<0.01), thougn blood flow was diminished in both groups. After surgery, cerebral blood flow on the affected side exceeded that on the unaffected side in Group A and transiently increased on postoperative day 1. Cerebral blood flow improved after surgery in both groups, with a significant difference in those changes over time (p<0.01). In both groups, cerebral re-expansion on postoperative days 7 and 30 correlated with cerebral blood flow on the affected side (p<0.05). The present results suggest that improvement in cerebral blood flow on the affected side is delayed in elderly patients, due to slower postoperative cerebral re-expansion. (author)

Bessel-Weighted Asymmetries in Semi Inclusive Deep Inelastic Scattering

International Nuclear Information System (INIS)

Boer, D.; Gamberg, L.; Musch, B.U.; Prokudin, A.

2011-01-01

The concept of weighted asymmetries is revisited for semi-inclusive deep inelastic scattering. We consider the cross section in Fourier space, conjugate to the outgoing hadron's transverse momentum, where convolutions of transverse momentum dependent parton distribution functions and fragmentation functions become simple products. Individual asymmetric terms in the cross section can be projected out by means of a generalized set of weights involving Bessel functions. Advantages of employing these Bessel weights are that they suppress (divergent) contributions from high transverse momentum and that soft factors cancel in (Bessel-) weighted asymmetries. Also, the resulting compact expressions immediately connect to previous work on evolution equations for transverse momentum dependent parton distribution and fragmentation functions and to quantities accessible in lattice QCD. Bessel weighted asymmetries are thus model independent observables that augment the description and our understanding of correlations of spin and momentum in nucleon structure.

Spin asymmetry in resonant electron-hydrogen elastic scattering

International Nuclear Information System (INIS)

McCarthy, I.E.; Shang, Bo.

1993-02-01

Differential cross sections and asymmetries at 90 deg. and 30 deg are calculated for electron-hydrogen elastic scattering over the energies of the lowest 1 S and 3 P resonances using a nine-state coupled-channels calculation with and without continuum effects, which are represented by an equivalent-local polarization potential. The polarization potential improves agreement with experiment in general for the spin-averaged cross sections. It is suggested that continuum effects would be critically tested by asymmetry measurement at 30 deg over the 1 S resonance. 7 refs., 4 figs

Origin of spin-dependent asymmetries in electron transmission through ultrathin ferromagnetic films

International Nuclear Information System (INIS)

Gokhale, M.P.; Mills, D.L.

1991-01-01

We present theoretical calculations of exchange asymmetries in the transmission of electrons through ultrathin films of ferromagnetic Fe. The results account nicely for the magnitude of the asymmetries observed by Pappas et al. in photoemission studies of Cu covered by an ultrathin film of Fe. We argue that exchange asymmetry in the transmissivity of the Fe film, rather than the spin dependence of the electron mean free path, is responsible for the effects reported by these authors

Perception of risk and communication among conventional and complementary health care providers involving cancer patients' use of complementary therapies: a literature review.

Science.gov (United States)

Stub, Trine; Quandt, Sara A; Arcury, Thomas A; Sandberg, Joanne C; Kristoffersen, Agnete E; Musial, Frauke; Salamonsen, Anita

2016-09-08

Communication between different health care providers (conventional and complementary) and cancer patients about their use of complementary therapies affects the health and safety of the patients. The aim of this study was to examine the qualitative research literature on the perception of and communication about the risk of complementary therapies between different health care providers and cancer patients. Systematic searches in six medical databases covering literature from 2000 to 2015 were performed. The studies were accessed according to the level of evidence and summarized into different risk situations. Qualitative content analysis was used to analyze the text data, and the codes were defined before and during the data analysis. Twenty-nine papers were included in the primary analysis and five main themes were identified and discussed. The main risk situations identified were 1. Differences in treatment concepts and philosophical values among complementary and conventional health care providers. 2. Adverse effects from complementary products and herbs due to their contamination/toxicity and interactions with conventional cancer treatment. 3. Health care physicians and oncologists find it difficult to recommend many complementary modalities due to the lack of scientific evidence for their effect. 4. Lack of knowledge and information about complementary and conventional cancer treatments among different health care providers. The risk of consuming herbs and products containing high level of toxins is a considerable threat to patient safety (direct risk). At the same time, the lack of scientific evidence of effect for many complementary therapies and differences in treatment philosophy among complementary and conventional health care providers potentially hinder effective communication about these threats with mutual patients (indirect risk). As such, indirect risk may pose an additional risk to patients who want to combine complementary therapies with

Frontal alpha asymmetry in OCD patients and unaffected first-degree relatives.

Science.gov (United States)

Grützmann, Rosa; Riesel, Anja; Klawohn, Julia; Heinzel, Stephan; Kaufmann, Christian; Bey, Katharina; Lennertz, Leonard; Wagner, Michael; Kathmann, Norbert

2017-08-01

Frontal electroencephalographic alpha asymmetry as an indicator of trait approach and trait inhibition systems has previously been studied in individuals with obsessive-compulsive disorder (OCD) with mixed results. We explored frontal alpha asymmetry as a possible risk factor in OCD by investigating a large sample of OCD patients (n = 113), healthy control participants (n = 113), and unaffected 1st-degree relatives of OCD patients (n = 37). Additionally, the relationship between OCD symptom dimensions and frontal alpha asymmetry was explored. OCD patients and healthy control participants did not differ in alpha asymmetry scores. Hence, the current results do not support the notion that OCD as a diagnostic entity is associated with a shift in frontal cortical activity. Furthermore, alpha asymmetry scores were not statistically related to specific OCD symptom dimensions. Reasons for inconsistent results in OCD are discussed and should be explored in future studies. Compared to OCD patients and healthy control participants, unaffected 1st-degree relatives of OCD patients showed increased left frontal activity. Such asymmetry has previously been found to be associated with positive affect and adaptive emotion regulation under stress. Because stressful life events play an important role in the onset and exacerbation of OCD, increased left frontal activity might serve as a resilience factor in unaffected 1st-degree relatives. Future studies should follow up on these results with longitudinal risk studies and pre- and posttherapy assessments to further explore causality of this putative factor. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Cerebral blood flow in temporal lobe epilepsy: a partial volume correction study

Energy Technology Data Exchange (ETDEWEB)

Giovacchini, Giampiero [University Milano-Bicocca, Milan (Italy); Bonwetsch, Robert; Theodore, William H. [National Institute of Neurological Diseases and Strokes, Clinical Epilepsy Section, Bethesda, MD (United States); Herscovitch, Peter [National Institutes of Health, PET Department, Clinical Center, Bethesda, MD (United States); Carson, Richard E. [Yale PET Center, New Haven, CT (United States)

2007-12-15

Previous studies in temporal lobe epilepsy (TLE) have shown that, owing to brain atrophy, positron emission tomography (PET) can overestimate deficits in measures of cerebral function such as glucose metabolism (CMR{sub glu}) and neuroreceptor binding. The magnitude of this effect on cerebral blood flow (CBF) is unexplored. The aim of this study was to assess CBF deficits in TLE before and after magnetic resonance imaging-based partial volume correction (PVC). Absolute values of CBF for 21 TLE patients and nine controls were computed before and after PVC. In TLE patients, quantitative CMR{sub glu} measurements also were obtained. Before PVC, regional values of CBF were significantly (p<0.05) lower in TLE patients than in controls in all regions, except the fusiform gyrus contralateral to the epileptic focus. After PVC, statistical significance was maintained in only four regions: ipsilateral inferior temporal cortex, bilateral insula and contralateral amygdala. There was no significant difference between patients and controls in CBF asymmetry indices (AIs) in any region before or after PVC. In TLE patients, AIs for CBF were significantly smaller than for CMR{sub glu} in middle and inferior temporal cortex, fusiform gyrus and hippocampus both before and after PVC. A significant positive relationship between disease duration and AIs for CMR{sub glu}, but not CBF, was detected in hippocampus and amygdala, before but not after PVC. PVC should be used for PET CBF measurements in patients with TLE. Reduced blood flow, in contrast to glucose metabolism, is mainly due to structural changes. (orig.)

Size and receptor density of glutamatergic synapses: a viewpoint from left-right asymmetry of CA3-CA1 connections

Directory of Open Access Journals (Sweden)

Yoshiaki Shinohara

2009-07-01

Full Text Available Synaptic plasticity is considered to be the main mechanism for learning and memory. Excitatory synapses in the cerebral cortex and hippocampus undergo plastic changes during development and in response to electric stimulation. It is widely accepted that this process is mediated by insertion and elimination of various glutamate receptors. In a series of recent investigations on left-right asymmetry of hippocampal CA3-CA1 synapses, glutamate receptor subunits have been found to have distinctive expression patterns that depend on the postsynaptic density (PSD area. Particularly notable are the GluR1 AMPA receptor subunit and NR2B NMDA receptor subunit, where receptor density has either a supra-linear (GluR1 AMPA or inverse (NR2B NMDAR relationship to the PSD area. We review current understanding of structural and physiological synaptic plasticity and propose a scheme to classify receptor subtypes by their expression pattern with respect to PSD area.

Studies of cerebral atrophy and regional cerebral blood flow in patients with Parkinson's disease

International Nuclear Information System (INIS)

Kitamura, Shin

1983-01-01

Cerebral atrophy and regional cerebral blood flow (rCBF) of 25 patients with Parkinson's disease were studied. The rCBF was measured with the intra-arterial Xe-133 injection method. The results obtained were as follows: 1) Sixty four % of Parkinson's disease patients showed ventricular dilation, and 76% of Parkinson's disease patients showed cortical atrophy on the CT scan, but we had to allow for the effects of the natural aging process on these results. 2) No correlation was recognized either between cerebral atrophy and the severity of Parkinson's disease, or between cerebral atrophy and the duration of Parkinson's disease. 3) In Parkinson's disease patients, the mean rCBF was lower than that of normal control subjects. The difference was even more remarkable in older patients. Only 40% of Parkinson's disease patients showed hyperfrontal pattern. 4) There was no correlation either between the mean rCBF and the severity of Parkinson's disease, or between the mean rCBF and the duration of Parkinson's disease. There was no significant difference between the mean rCBF of Parkinson's disease patients receiving levodopa and that of untreated patients. 5) The mean rCBF decreased in patients with cerebral atrophy on the CT scan. 6) Parkinson's disease patients with intellectual impairment showed cerebral atrophy and a remarkable decrease of the mean rCBF. 7) The effect of aging on cerebral atrophy on the CT scan had to be allowed for, but judging from the decrease of the mean rCBF, the cerebral cortex is evidently involved in Parkinson's disease. 8) The rCBF decline in Parkinson's disease patients may be related with the diminished cortical metabolic rate due to a remote effect of striatal dysfunction and a disturbance of mesocortical dopaminergic pathways. (J.P.N.)

Studies of cerebral atrophy and regional cerebral blood flow in patients with Parkinson's disease

Energy Technology Data Exchange (ETDEWEB)

Kitamura, Shin [Nippon Medical School, Tokyo

1983-04-01

Cerebral atrophy and regional cerebral blood flow (rCBF) of 25 patients with Parkinson's disease were studied. The rCBF was measured with the intra-arterial Xe-133 injection method. The results obtained were as follows: 1) Sixty four % of Parkinson's disease patients showed ventricular dilation, and 76% of Parkinson's disease patients showed cortical atrophy on the CT scan, but we had to allow for the effects of the natural aging process on these results. 2) No correlation was recognized either between cerebral atrophy and the severity of Parkinson's disease, or between cerebral atrophy and the duration of Parkinson's disease. 3) In Parkinson's disease patients, the mean rCBF was lower than that of normal control subjects. The difference was even more remarkable in older patients. Only 40% of Parkinson's disease patients showed hyperfrontal pattern. 4) There was no correlation either between the mean rCBF and the severity of Parkinson's disease, or between the mean rCBF and the duration of Parkinson's disease. There was no significant difference between the mean rCBF of Parkinson's disease patients receiving levodopa and that of untreated patients. 5) The mean rCBF decreased in patients with cerebral atrophy on the CT scan. 6) Parkinson's disease patients with intellectual impairment showed cerebral atrophy and a remarkable decrease of the mean rCBF. 7) The effect of aging on cerebral atrophy on the CT scan had to be allowed for, but judging from the decrease of the mean rCBF, the cerebral cortex is evidently involved in Parkinson's disease. 8) The rCBF decline in Parkinson's disease patients may be related with the diminished cortical metabolic rate due to a remote effect of striatal dysfunction and a disturbance of mesocortical dopaminergic pathways.

Tuning piezoresistive transduction in nanomechanical resonators by geometrical asymmetries

Energy Technology Data Exchange (ETDEWEB)

Llobet, J.; Sansa, M.; Lorenzoni, M.; Pérez-Murano, F., E-mail: francesc.perez@csic.es [Institut de Microelectrònica de Barcelona (IMB-CNM CSIC), Campus UAB, 08193 Bellaterra (Spain); Borrisé, X. [Institut Català de Nanociència i Nanotecnologia (ICN2), Campus UAB, 08193 Bellaterra Spain (Spain); San Paulo, A. [Instituto de Microelectrónica de Madrid (IMM-CSIC), 28760 Tres Cantos, Madrid (Spain)

2015-08-17

The effect of geometrical asymmetries on the piezoresistive transduction in suspended double clamped beam nanomechanical resonators is investigated. Tapered silicon nano-beams, fabricated using a fast and flexible prototyping method, are employed to determine how the asymmetry affects the transduced piezoresistive signal for different mechanical resonant modes. This effect is attributed to the modulation of the strain in pre-strained double clamped beams, and it is confirmed by means of finite element simulations.

Measurement of transverse momentum dependent asymmetries with COMPASS experimental at CERN

Energy Technology Data Exchange (ETDEWEB)

Venugopal, Girisan

2007-07-01

The COMPASS experiment, which started running at the European Council for Nuclear Research, CERN, in Geneva in 2001, is currently investigating in a wide ranging programme the spin structure of the nucleon through deep-inelastic scattering (DIS). The experiment uses a polarized muon beam and a polarized deuterium target, which together allow access to all terms of the polarized DIS cross-section. Two of the most important functions which COMPASS is designed to full are a precision measurement of the gluon polarization {delta}G and the investigation of the transverse spin effects, specially extracting the transverse polarized quark distribution functions {delta}{sub T}q. In Semi-Inclusive DIS of polarized leptons on a transversely polarized target, eight azimuthal modulations appear in the cross-section. Within the QCD parton model, four azimuthal asymmetries can be interpreted at leading order, two of them being the Collins and Sivers asymmetries. The other two leading twist asymmetries are related to different transverse momentum dependent quark distribution functions. There are four additional asymmetries which can be interpreted as twist-three contributions. This thesis describes the analysis with the data taken with transverse spin configuration during the COMPASS beam-time 2002-2004, resulting in the extraction of the eight Transverse Momentum Dependent (TMD) asymmetries. (orig.)

Measurement of transverse momentum dependent asymmetries with COMPASS experimental at CERN

International Nuclear Information System (INIS)

Venugopal, Girisan

2007-01-01

The COMPASS experiment, which started running at the European Council for Nuclear Research, CERN, in Geneva in 2001, is currently investigating in a wide ranging programme the spin structure of the nucleon through deep-inelastic scattering (DIS). The experiment uses a polarized muon beam and a polarized deuterium target, which together allow access to all terms of the polarized DIS cross-section. Two of the most important functions which COMPASS is designed to full are a precision measurement of the gluon polarization ΔG and the investigation of the transverse spin effects, specially extracting the transverse polarized quark distribution functions Δ T q. In Semi-Inclusive DIS of polarized leptons on a transversely polarized target, eight azimuthal modulations appear in the cross-section. Within the QCD parton model, four azimuthal asymmetries can be interpreted at leading order, two of them being the Collins and Sivers asymmetries. The other two leading twist asymmetries are related to different transverse momentum dependent quark distribution functions. There are four additional asymmetries which can be interpreted as twist-three contributions. This thesis describes the analysis with the data taken with transverse spin configuration during the COMPASS beam-time 2002-2004, resulting in the extraction of the eight Transverse Momentum Dependent (TMD) asymmetries. (orig.)

First measurement of the Sivers asymmetry for gluons using SIDIS data

Directory of Open Access Journals (Sweden)

C. Adolph

2017-09-01

Full Text Available The Sivers function describes the correlation between the transverse spin of a nucleon and the transverse motion of its partons. For quarks, it was studied in previous measurements of the azimuthal asymmetry of hadrons produced in semi-inclusive deep inelastic scattering of leptons off transversely polarised nucleon targets, and it was found to be non-zero. In this letter the evaluation of the Sivers asymmetry for gluons is presented. The contribution of the photon–gluon fusion subprocess is enhanced by requiring two high transverse-momentum hadrons. The analysis method is based on a Monte Carlo simulation that includes three hard processes: photon–gluon fusion, QCD Compton scattering and the leading-order virtual-photon absorption process. The Sivers asymmetries of the three processes are simultaneously extracted using the LEPTO event generator and a neural network approach. The method is applied to samples of events containing at least two hadrons with large transverse momentum from the COMPASS data taken with a 160 GeV/c muon beam scattered off transversely polarised deuterons and protons. With a significance of about two standard deviations, a negative value is obtained for the gluon Sivers asymmetry. The result of a similar analysis for a Collins-like asymmetry for gluons is consistent with zero.

Cerebral blood measurements in cerebral vascular disease: methodological and clinical aspects

International Nuclear Information System (INIS)

Fieschi, C.; Lenzi, G.L.

1982-01-01

This paper is devoted mainly to studies performed on acute cerebral vascular disease with the invasive techniques for the measurement of regional cerebral blood flow (rCBF). The principles of the rCBF method are outlined and the following techniques are described in detail: xenon-133 inhalation method, xenon-133 intravenous method and emission tomography methods. (C.F.)

CT classification and clinical prognosis of cerebral infarction in the area of middle cerebral artery

International Nuclear Information System (INIS)

Konno, Jyoji

1983-01-01

Computerized tomographies (CT) were repeatedly scanned on 70 patients with cerebral infarction in the middle cerebral artery. Low density area (LDA) was measured with HounFsfield's Unit (HU) and studied on the progressive changes. Classification of LDA was attempted and studied on correlation with mass effect, contrast enhancement, angiographical findings, clinical symptoms and prognosis. It was considered that important points of diagnosis of cerebral infarction were timing of examination of CT and determination of LDA with HUF. It was also thought that CT classification of LDA was usefull to estimate prognosis of the patients with cerebral infarction. (author)

[Lateralization of behavioral reactions and otolith asymmetry].

Science.gov (United States)

Lychakov, D V

2013-01-01

Lateralized behavior is widely spread among vertebrate animals and is determined first of ally by structural-functional brain asymmetry as well as by the presence of somatic and visceral asymmetry. Some kinds of asymmetric reactions are suggested to be due to the presence of asymmetry at the level of sense organs, in particular, of otolith organs. This review presents data on value and character of otolith asymmetry (OA) in animals of various species and classes, on action upon it of weightlessness and hypergravity; the problem of effect of OA on vestibular and auditory functions is considered. In symmetric vertebrates, OA has been shown to be of fluctuation character and its chi coefficient varies in diapason from -0.2 to 0.2; in the overwhelmed majority of individuals, /chi/ otolith organs to work coordinately; this it why OA is at the equally low level regardless of the individual's taxonomic and ecologic position, its size, age, and otolith growth rate. Individuals with abnormally high OA level can experience difficulties in analysis of auditory and vestibular stimuli, therefore in nature the majority of such individuals are eliminated in the process of natural selection. Unlike symmetrical vertebrates, labyrinths of many Pleuronectiformes have pronounced OA--otoliths of the lower labyrinth, on a average, are significantly heavier than those of the upper labyrinth. Their organs are the only example when OA with directed character seem to play an essential role in lateralized behavior and are suggested to be used in the spatial localization of the sound source. The short-time action of weightlessness and relatively weak hypergravity ( or = 3g, as well as some diseases and shifts connected with processes of aging can enhance OA and cause several functional disturbances.

The relation between electroencephalogram asymmetry and attention biases to threat at baseline and under stress

OpenAIRE

Pérez-Edgar, Koraly; Kujawa, Autumn; Nelson, S. Katherine; Cole, Claire; Zapp, Daniel J.

2013-01-01

Electroencephalogram (EEG) asymmetry in the alpha frequency band has been implicated in emotion processing and broad approach-withdrawal motivation systems. Questions remain regarding the cognitive mechanisms that may help elucidate the observed links between EEG asymmetry and patterns of socioemotional functioning. The current study observed frontal EEG asymmetry patterns at rest and under social threat among young adults (N=45, M=21.1 years). Asymmetries were, in turn, associated with perfo...

Relation of plasma homocyst(e)ine to cerebral infarction and cerebral atherosclerosis.

Science.gov (United States)

Yoo, J H; Chung, C S; Kang, S S

1998-12-01

A number of investigations support the theory that the elevated plasma homocyst(e)ine is associated with occlusive vascular disease. The aim of this study is to examine whether moderate hyperhomocyst(e)inemia is an independent risk factor for cerebral infarction. In addition, we examined the association between plasma homocyst(e)ine and the severity of cerebral atherosclerosis. We conducted a hospital-based case-control study with 140 male controls and 78 male patients with nonfatal cerebral infarction, aged between 39 and 82 years. Plasma homocyst(e)ine levels were analyzed in 218 subjects. Fifty-five patients were evaluated for cerebral vascular stenosis by MR angiography. The mean plasma level of homocyst(e)ine was higher in cases than in controls (11.8+/-5.6 versus 9.6+/-4.1 micromol/L; P=0.002). The proportion of subjects with moderate hyperhomocyst(e)inemia was significantly higher in cases than in controls (16.7% versus 5.0%; P=0.004). Based on the logistic regression model, the odds ratio of the highest 5% of homocyst(e)ine levels in control group was 4.17 (95% confidence interval, 3.71 to 4. 71)(P=0.0001). After additional adjustment for total cholesterol, hypertension, smoking, diabetes, and age, the odds ratio was 1.70 (95% confidence interval, 1.48 to 1.95) (P=0.0001). The plasma homocyst(e)ine levels of patients having vessels with 3 or 2 stenosed sites were significantly higher than those of patients having vessels with 1 stenosed site or normal vessels (14.6+/-1.4, 11.0+/-1.4 versus 7.8+/-1.5, 8.9+/-1.4 micromol/L respectively; P<0. 02). Multiple logistic regression analysis revealed that moderate hyperhomocyst(e)ienemia was significantly associated with the number of stenosed vessels (P=0.001). These findings suggest that moderate hyperhomocyst(e)inemia is an independent risk factor for cerebral infarction and may predict the severity of cerebral atherosclerosis in patients with cerebral infarction.

Variability of gait, bilateral coordination, and asymmetry in women with fibromyalgia.

Science.gov (United States)

Heredia-Jimenez, J; Orantes-Gonzalez, E; Soto-Hermoso, V M

2016-03-01

To analyze how fibromyalgia affected the variability, asymmetry, and bilateral coordination of gait walking at comfortable and fast speeds. 65 fibromyalgia (FM) patients and 50 healthy women were analyzed. Gait analysis was performed using an instrumented walkway (GAITRite system). Average walking speed, coefficient of variation (CV) of stride length, swing time, and step width data were obtained and bilateral coordination and gait asymmetry were analyzed. FM patients presented significantly lower speeds than the healthy group. FM patients obtained significantly higher values of CV_StrideLength (p=0.04; pGait asymmetry only showed significant differences in the fast condition. FM patients walked more slowly and presented a greater variability of gait and worse bilateral coordination than healthy subjects. Gait asymmetry only showed differences in the fast condition. The variability and the bilateral coordination were particularly affected by FM in women. Therefore, variability and bilateral coordination of gait could be analyzed to complement the gait evaluation of FM patients. Copyright © 2016 Elsevier B.V. All rights reserved.