855 research outputs found
The new heliospheric magnetic field: Observational implications
A summary of the new model of the heliospheric magnetic field and its observational implications is presented. We first introduce a global model for the steady-state configuration in the low corona and discuss solar and heliospheric implications of the resulting field configuration. Finally, we compare the effects of this model with random transport of field-lines due to reconnection on the solar surface and to the dynamic turbulent transport of magnetic field-lines. © 1999 American Institute of Physics.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87723/2/87_1.pd
The transition from slow to fast solar wind: Charge state composition and electron observations
The charge state composition is a very sensitive measure for the electron properties at around 2 solar radii heliocentric distance. Even though the basic principle of the charge-state freeze-in process is rather well understood, it is not clear how the non-thermal properties of the electron distribution functions influence the frozen-in charge states. The obvious question to ask, then, is whether in situ electrons exhibit the same temporal variations as the charge state composition. Using SWICS/ACE and 3DP/WIND data, we find that the core electrons are dominated by local effects like compression and have no memory of their coronal origin. Supra-thermal electrons, on the other hand, show a clear correlation with the charge state data. © 1999 American Institute of Physics.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87725/2/495_1.pd
Isotopic Composition of Solar Wind Calcium: First in Situ Measurement by CELIAS/MTOF on Board SOHO
We present first results on the Ca isotopic abundances derived from the high
resolution Mass Time-of-Flight (MTOF) spectrometer of the charge, element, and
isotope analysis system (CELIAS) experiment on board the Solar and Heliospheric
Observatory (SOHO). We obtain isotopic ratios 40Ca/42Ca = (128+-47) and
40Ca/44Ca = (50+-8), consistent with terrestrial values. This is the first in
situ determination of the solar wind calcium isotopic composition and is
important for studies of stellar modeling and solar system formation since the
present-day solar Ca isotopic abundances are unchanged from their original
isotopic composition in the solar nebula.Comment: 14 pages, 3 figure
Successful neuropsychological rehabilitation in a patient with Cerebellar Cognitive Affective Syndrome
The objective of this case study was to describe the neuropsychological rehabilitation of a 16-year-old patient who presented a Cerebellar Cognitive Affective Syndrome (CCAS) following a bilateral cerebellar hemorrhage. The patient presented severe and diffuse cognitive deficits, massive behavioral disorders, and emotion regulation difficulties. The cognitive rehabilitation was performed in the chronic phase (one year after the onset of the hemorrhage) using a transdisciplinary neurobehavioral approach based on the patient's favorite interest (soccer). A significant behavioral and cognitive improvement was observed. The patient became progressively independent in all activities of daily living and was discharged home. The Functional Independence Measure at discharge was 124/126 (vs. 37/126 at entry). The patient was able to complete his schooling despite the mild cognitive and behavioral sequelae. This first description of the use of neurobehavioral therapy in a case of chronic CCAS suggests that (a) major clinical improvement can occur more than one year after the onset of the CCAS, showing the importance of long-term and intensive neurorehabilitation; and (b) when the cerebellum cannot properly play its regulator role in cognition, neuropsychological intervention through a behavioral and cognitive approach can be of great help by acting as an external modulator to help the patient regain control over himself
Work in Hypoxic Conditions-Consensus Statement of the Medical Commission of the Union Internationale des Associations d'Alpinisme (UIAA MedCom)
Objectives: The Commission gives recommendations on how to provide health and safety for employees in different kinds of low oxygen atmospheres. So far, no recommendations exist that take into account the several factors we have outlined in this report. Methods: The health and safety recommendations of several countries were analysed for their strength and deficiencies. The scientific literature was checked (Medline, etc.) and evaluated for relevance of the topic. Typical situations of work in hypoxia were defined and their specific risks described. Specific recommendations are provided for any of these situations. Results: We defined four main groups with some subgroups (main risk in brackets): short exposure (pressure change), limited exposure (acute altitude disease), expatriates (chronic altitude disease), and high-altitude populations (re-entry pulmonary oedema). For healthy unacclimatized persons, an acute but limited exposure down to 13% O2 does not cause a health risk. Employees should be advised to leave hypoxic areas for any break, if possible. Detailed advice is given for any other situation and pre-existing diseases. Conclusions: If the specific risk of the respective type of hypoxia is taken into account, a pragmatic approach to provide health and safety for employees is possible. In contrast to other occupational exposures, a repeated exposure as often as possible is of benefit as it causes partial acclimatization. The consensus statement was approved by written consent in lieu of a meeting in July 200
The cell adhesion molecule L1 regulates the expression of choline acetyltransferase and the development of septal cholinergic neurons
Mutations in the L1 gene cause severe brain malformations and mental retardation. We investigated the potential roles of L1 in the regulation of choline acetyltransferase (ChAT) and in the development of septal cholinergic neurons, which are known to project to the hippocampus and play key roles in cognitive functions. Using stereological approaches, we detected significantly fewer ChAT-positive cholinergic neurons in the medial septum and vertical limb of the diagonal band of Broca (MS/VDB) of 2-week-old L1-deficient mice compared to wild-type littermates (1644 ± 137 vs. 2051 ± 165, P = 0.038). ChAT protein levels in the septum were 53% lower in 2-week-old L1-deficient mice compared to wild-type littermates. ChAT activity in the septum was significantly reduced in L1-deficient mice compared to wild-type littermates at 1 (34%) and 2 (40%) weeks of age. In vitro, increasing doses of L1-Fc induced ChAT activity in septal neurons with a significant linear trend (*P = 0.0065). At 4 weeks of age in the septum and at all time points investigated in the caudate-putamen (CPu), the number of ChAT-positive neurons and the levels of ChAT activity were not statistically different between L1-deficient mice and wild-type littermates. The total number of cells positive for the neuronal nuclear antigen (NeuN) in the MS/VDB and CPu was not statistically different in L1-deficient mice compared to wild-type littermates, and comparable expression of the cell cycle marker Ki67 was observed. Our results indicate that L1 is required for the timely maturation of septal cholinergic neurons and that L1 promotes the expression and activity of ChAT in septal neurons
Cerebral mGluR5 availability contributes to elevated sleep need and behavioral adjustment after sleep deprivation.
Increased sleep time and intensity quantified as low-frequency brain electrical activity after sleep loss demonstrate that sleep need is homeostatically regulated, yet the underlying molecular mechanisms remain elusive. We here demonstrate that metabotropic glutamate receptors of subtype 5 (mGluR5) contribute to the molecular machinery governing sleep-wake homeostasis. Using positron emission tomography, magnetic resonance spectroscopy, and electroencephalography in humans, we find that increased mGluR5 availability after sleep loss tightly correlates with behavioral and electroencephalographic biomarkers of elevated sleep need. These changes are associated with altered cortical myo-inositol and glycine levels, suggesting sleep loss-induced modifications downstream of mGluR5 signaling. Knock-out mice without functional mGluR5 exhibit severe dysregulation of sleep-wake homeostasis, including lack of recovery sleep and impaired behavioral adjustment to a novel task after sleep deprivation. The data suggest that mGluR5 contribute to the brain's coping mechanisms with sleep deprivation and point to a novel target to improve disturbed wakefulness and sleep
The Transition Between Fast and Slow Solar Wind from Composition Data
The transition between coronal hole associated fast solar wind and slow solar wind is studied using data from the high resolution mass spectrometer SWICS on ACE. We discuss the data in the framework of a recent theory about the global heliospheric magnetic field and conclude that the data are consistent with magnetic connections between field-lines in the fast and in the slow wind.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/43792/1/11214_2004_Article_234059.pd
Fragebogen zur Behandlungszufriedenheit in der stationären Kinder- und Jugendpsychiatrie (FBZ-KJP) [Questionnaire on Treatment Satisfaction in Inpatient Child and Adolescent Psychiatry (FBZ-KJP) - Results of a Swiss Pilot Study]
Questionnaire on Treatment Satisfaction in Inpatient Child and Adolescent Psychiatry (FBZ-KJP) - Results of a Swiss Pilot Study Abstract. Objectives: Patient satisfaction is an established indicator for medical interventions. Existing questionnaires for the assessment of patient satisfaction in child and adolescent psychiatry are too global to target quality improvement in child and adolescent psychiatric hospitals. The assessment of patient satisfaction in child and adolescent psychiatry is very challenging because specific demands (development status, role of parents in treatment) have been taken into account. Therefore, an expert team leaded by the Swiss Society of Child and Adolescent Psychiatry developed a targeted instrument to assess patient satisfaction in both language regions (i. e., German and French). Methods: The article reviews the development of a new child and adolescent psychiatric questionnaire for the assessment of patient satisfaction as well as the findings of a survey conducted in a representative sample of 174 patients and 145 parents in six hospitals. Results: The internal consistency (Cronbach's α = .93) is excellent. The questionnaire has high levels of both convergence and face validity, and the correlation with the Client Satisfaction Questionnaire (CSQ-8) is ρ = .80 (patient-report) and .83 (parent-report). Furthermore, this questionnaire reveals the relative strengths and weaknesses of individual hospitals. The correlation between patient and parent assessment is, as expected, moderate (ρ = .29, for the total score and ρ = .39 for the CSQ-8). Conclusions: The Patient Satisfaction Questionnaire can be recommended to professionals as a standard for collecting data on client satisfaction within child and adolescent psychiatry
Simultaneous high Fe charge state measurements by solar energetic particle and solar wind instruments
During the May 2–3, 1998 CME event, iron charge state distributions were observed on the ACE spacecraft simultaneously in both solar energetic particles and the solar wind. Surprisingly, common signatures were found, even though the energy of these two particle populations differ by about two orders of magnitude. At the beginning of the event a substantial shift towards higher charge states (Q ≥ 14)(Q⩾14) was detected for Fe nearly simultaneously in solar energetic particles by SEPICA, and in the solar wind by SWICS. The onset in the solar wind was somewhat more gradual, beginning approximately two hours before the rather sudden onset in the solar energetic particles. The high iron charge states coincided approximately with the magnetic cloud associated with the CME. Later, during the cloud passage, periods of high and unusually low, iron ionization states were observed in the solar wind. Just after the passage of the cloud, iron with high charge states again appeared in both energetic particles and the solar wind. Transport and acceleration scenarios will be discussed as possible explanations of this unusual event. © 2000 American Institute of Physics.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87339/2/139_1.pd
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