ABSTRACT
Theories with an extra spin-two field coupled to gravity admit a massive phase with broken Lorentz symmetry. While the equivalence principle is respected, the Newtonian potentials are in general modified, but they may be protected by a scale symmetry of the coupling term. The gravitational waves phenomenology is quite rich: two gravitons, one massive and one massless, oscillate and propagate with distinct velocities, different from the speed of light. A time of flight difference between gravitons and photons from a common source would provide a clear signal of this theory.
ABSTRACT
The curvaton and inhomogeneous reheating scenarios for the generation of the cosmological curvature perturbation on large scales represent an alternative to the standard slow-roll scenario. The basic assumption of these mechanisms is that the initial curvature perturbation due to the inflaton field is negligible. This is usually attained by lowering the energy scale of inflation, thereby concluding that the amount of gravitational waves produced during inflation is highly suppressed. We show that the curvaton and inhomogeneous reheating scenarios are compatible with a level of gravity-wave fluctuations which may well be observed in future satellite experiments.
ABSTRACT
Multiple system atrophy (MSA) is a disease causing parkinsonism in which response to levodopa is classically absent, poor, or transient. Idiopathic Parkinson's disease (IPD) itself, which responds favorably to levodopa, has been associated with the development of disease-related depression. Over and above the clinical and pathological characteristics of IPD, MSA causes additional, more widespread, clinical and pathological deficits. We have compared motor disability and mood in 12 patients with MSA and 12 with IPD. There was more severe motor disability, but no clinical evidence of depression among the MSA patients studied, and their Beck Depression Inventory scores did not differ significantly from the group with IPD. We conclude that depression does not appear to be more common in MSA than in IPD.
Subject(s)
Autonomic Nervous System Diseases/diagnosis , Depressive Disorder/diagnosis , Neurocognitive Disorders/diagnosis , Olivopontocerebellar Atrophies/diagnosis , Parkinson Disease/diagnosis , Activities of Daily Living/psychology , Adult , Aged , Autonomic Nervous System Diseases/physiopathology , Autonomic Nervous System Diseases/psychology , Brain/physiopathology , Depressive Disorder/physiopathology , Depressive Disorder/psychology , Female , Humans , Male , Middle Aged , Neurocognitive Disorders/physiopathology , Neurocognitive Disorders/psychology , Neuropsychological Tests , Olivopontocerebellar Atrophies/physiopathology , Olivopontocerebellar Atrophies/psychology , Parkinson Disease/physiopathology , Parkinson Disease/psychology , Personality Assessment , Pilot Projects , Pyramidal Tracts/physiopathology , Spinal Cord/physiopathologyABSTRACT
The psychiatric complications of epilepsy are varied but may be considered under two main groups--those directly related to ictal activity and those that occur during the inter-ictal period. Epilepsy and psychiatry are also similar in that they cause a great deal of social difficulties and restriction in terms of activities and employment opportunities because of the associated stigma and prejudice. The various complications are discussed and illustrated with case studies where appropriate.
Subject(s)
Epilepsy/psychology , Mental Disorders/etiology , Adult , Aggression , Cognition Disorders/etiology , Confusion/etiology , Epilepsy/physiopathology , Female , Humans , Male , Mood Disorders/etiology , Personality Disorders/etiology , Psychotic Disorders/etiology , Schizophrenia/etiology , Sexual Dysfunction, Physiological/etiologyABSTRACT
Calcification in the basal ganglia in the brain is, as a rule, asymptomatic and is therefore observed as an incidental finding at CT examination for other cerebral conditions e.g. tumours or haemorrhage. The question is whether incidental finding of calcification in the basal ganglia indicates the need for further supplementary investigations. Three case histories and study of the literature are quoted to illustrate this. It is concluded that investigation is not indicated in patients over the age of 50 years with limited, bilateral, symmetrical calcifications in the globi pallidi. In patients under 50 years, investigation in the form of detailed history taking, neurological examination and haematological investigation is indicated.
Subject(s)
Basal Ganglia Diseases/diagnostic imaging , Calcinosis/diagnostic imaging , Adolescent , Age Factors , Aged , Basal Ganglia Diseases/pathology , Cerebral Infarction/diagnostic imaging , Cerebral Infarction/pathology , Cerebrovascular Disorders/diagnosis , Cerebrovascular Disorders/pathology , Diagnosis, Differential , Female , Humans , Hypoparathyroidism/diagnosis , Hypoparathyroidism/pathology , Male , Middle Aged , Tomography, X-Ray ComputedABSTRACT
The neuroleptic malignant syndrome is a serious complication associated with the use of antipsychotic drugs that has received a great deal of interest in recent times. Although its aetiology has not been fully understood, it often occurs in association with underlying brain disease and physical debilitation. Two such cases are described. The various hypotheses concerning the aetiology and pathogenesis of this condition are also discussed.
Subject(s)
Neuroleptic Malignant Syndrome/etiology , Adult , Brain Diseases/complications , Female , Fluphenazine/adverse effects , Humans , Male , Middle Aged , Postoperative Complications , Risk Factors , Water Intoxication/complicationsABSTRACT
Gelastic epilepsy is an uncommon phenomenon and it is particularly uncommon in adults. This paper describes a case of gelastic epilepsy in a middle-aged woman presented in a psychiatric hospital. A short history of the condition, clinical and electroencephalographic findings in gelastic epilepsy and causes of pathological laughter are discussed.
