Generation of thermofield double states and critical ground states with a quantum computer.

Finite-temperature phases of many-body quantum systems are fundamental to phenomena ranging from condensed-matter physics to cosmology, yet they are generally difficult to simulate. Using an ion trap quantum computer and protocols motivated by the quantum approximate optimization algorithm (QAOA), we generate nontrivial thermal quantum states of the transverse-field Ising model (TFIM) by preparing thermofield double states at a variety of temperatures. We also prepare the critical state of the TFIM at zero temperature using quantum-classical hybrid optimization. The entanglement structure of thermofield double and critical states plays a key role in the study of black holes, and our work simulates such nontrivial structures on a quantum computer. Moreover, we find that the variational quantum circuits exhibit noise thresholds above which the lowest-depth QAOA circuits provide the best results.

Singular behavior of eigenstates in Anderson's model of localization.

We observe an apparent singularity in the electronic properties of the Anderson model of localization with bounded diagonal disorder, which is clearly distinct from the well-established mobility edge (localization-delocalization transition) that occurs in dimensions d > 2. We present results of numerical calculations for Anderson's original uniform (box) distribution of on-site disorder in dimensions d = 1, 2, and 3. To establish this hitherto unreported behavior, and to understand its evolution with disorder, we contrast the behavior of two different measures of the localization length of the electronic wave functions-the averaged inverse participation ratio and the Lyapunov exponent. Our data suggest that Anderson's model exhibits richer behavior than has been established so far.

Novel thermostable lipase from Bacillus circulans IIIB153: comparison with the mesostable homologue at sequence and structure level.

Thermophilic Bacillus circulans IIIB153 isolated from hot springs of North West Himalayas, India, produced an extracellular lipase, which exhibited significant biofilm disruption property on the static biofilm disruption model with a single species of Actinomyces viscosous. The gene encoding the lipase was cloned and overexpressed in Escherichia coli. Recombinant Bacillus circulans lipase (BCL), a monomer with molecular mass of 43 kDa also exhibited significant biofilm disruption activity. The enzyme was optimally active at 60°C, pH 8.5 and retained >70% of its original activity after 1 h incubation at 60°C. 3D structure of BCL developed by homology modeling showed a typical α/ß hydrolase fold, a characteristic feature of lipolytic enzymes. Comparison of thermostable BCL with mesostable lipase from Chromobacterium viscosum at the sequence and structure level showed distinct variations in the structural features, with the presence of a high content of proline residues, aromatic amino acids and salt bridges. These features along with the presence of zinc-binding site observed in BCL structure could have a potential role in thermal stability of the enzyme.

Recovery from rabies, a universally fatal disease.

BACKGROUND: Rabies is a zoonosis transmitted via the bites of various mammals, primarily dogs and bats. Known since antiquity, this disease may have the deadliest human fatality rates and is responsible for approximately 65,000 deaths worldwide per year. CASE PRESENTATION: We report the case details of a 13-year-old boy from India belonging to a South Asian ethnicity, who presented with altered sensorium one month following a dog bite. He did not receive the active rabies immunization and was managed with supportive therapy. The patient had extensive T2W (T2 weighted)/fluid attenuation and inversion recovery (FLAIR) hyper intensities involving the deep gray matter of the cerebral hemispheres, hippocampus, brainstem, and cerebellum. The diagnosis was confirmed by the demonstration of the rabies antigen from a nuchal skin biopsy and a corneal smear. The patient had a slow but significant recovery over four months and was discharged from the hospital in stable condition with severe neurological sequelae. CONCLUSION: We report a unique case of survival after infection with a universally fatal disease.

HIV infection with myasthenia gravis.

A soldier presented in Jan 2002 with features of proximal myopathy and diplopia. Clinically he had features of myasthenia gravis, which was confirmed by significantly positive neostigmine test, decremental response on electrophysiological study and raised acetylcholine receptor antibody titres. He also tested positive for HIV during evaluation of a cervical lymph node detected incidentally. He responded well to neostigmine and has remained asymptomatic on follow up.

Visual scanning of faces correlates with schizophrenia symptomatology.

1. The purpose of this study was to examine whether quantitative measures of visual scanning of faces correlated with the severity of symptoms in patients with schizophrenia. 2. Preattentive visual fixations (fixations less than or equal to 50.1 ms in duration) were measured while 16 subjects with chronic schizophrenia and 38 comparison subjects scanned slides of human faces. 3. A significant inverse correlation was found between the number of preattentive fixations exhibited during 10 seconds of facial scanning and total Brief Psychiatric Rating Scale (BPRS) scores. 4. This study suggests that measures that probe preattentive processing during scanning of faces could represent a novel paradigm for studying the symptoms of schizophrenia.

Anxiety and pupil reactivity in cocaine dependent subjects endorsing cocaine-induced paranoia: preliminary report.

There has been the clinical impression that people with higher levels of anxiety and central arousal are more prone to develop cocaine-induced paranoia (CIP), but this notion has not been formally studied. In the current study, we examined the differences between 28 CIP-endorsing and 16 CIP-denying chronic cocaine users in their levels of state and trait anxiety as measured by the Spielberger State-Tait Anxiety Inventory. We also studied levels of central arousal and reactivity using pupil size measures both during exposure to neutral, abstract, non-drug cues, and after exposure to a cocaine cue. Levels of trait (but not state) anxiety were significantly higher in the CIP group than in the non-CIP group. Moreover, while there were no significant pupil size differences or changes between the two groups while viewing neutral, abstract video images, the CIP group had significantly greater pupillary dilation in response to a video image of crack cocaine than did the non-CIP group. These significant differences remained even after covarying for anxiety scores. The study findings seem relevant to studies of autonomic reactivity in response to drug cues in cocaine-dependent patients; such studies might remain attentive to potential cue reactivity differences between patients endorsing and those denying CIP. Finally, this is the first study showing higher trait anxiety in patients with CIP.

Pupillary changes associated with the development of stimulant-induced mania: a case report.

A 30-year-old cocaine-dependent man who was a subject in a study evaluating the anticraving efficacy of the stimulant medication diethylpropion (DEP) became manic during his second week on the study drug. Pupillometric changes while on DEP, especially changes in the total power of pupillary oscillation, were dramatically different than those observed in the eight other study subjects who did not become manic. The large changes in total power of pupillary oscillation occurred a few days before the patient became fully manic. Such medication-associated changes in the total power of pupillary oscillation might be of utility in identifying persons at risk for manic-like adverse effects during the medical use of psychomotor stimulants or sympathomimetic agents.

Pupillometric changes during gradual opiate detoxification correlate with changes in symptoms of opiate withdrawal as measured by the Weak Opiate Withdrawal Scale.

The relationship between pupil size and subjective symptoms of opiate withdrawal during gradual opiate agonist detoxification has not yet been studied. In the current study, the authors sought to determine the relationship between pupil size and intensity of opiate withdrawal symptoms. To accomplish this, they examined 19 subjects meeting DSM-IV criteria for opiate dependence (304.00) on agonist therapy. All subjects were undergoing opiate detoxification with either methadone or the longer-acting 1-alpha acetylmethadol (LAMM). During two separate visits, subjects' pupil sizes were assessed in the dark using a pupillometer. At each visit, subjects completed two standardized assessment tools (the Subjective Opiate Withdrawal Scale [SOWS] and the Weak Opiate Withdrawal Scale [WOWS]) for measuring subjective symptoms of opiate withdrawal. It was found that changes in pupil size significantly correlated with WOWS, but not with SOWS, scores. Larger pupil sizes were associated with less withdrawal distress. The sensitivity of the pupillometric test to detect increases in opiate craving during opiate agonist medication reduction was 92%, with a specificity of 57%. The predictive value of a positive test was 79%, whereas the predictive value of a negative test was 80%. Pupillometry may provide an objective measure of the intensity of opiate withdrawal in subjects during gradual methadone detoxification.

L-tyrosine pharmacotherapy of schizophrenia: preliminary data.

The utility of L-tyrosine (10 g/day in four divided doses) as an adjuvant to molindone (150 mg/day) in the treatment of schizophrenia was investigated using a placebo-controlled, double-blind crossover design (3 weeks on L-tyrosine, 3 weeks on placebo). The objective of this inpatient study was to increase dopaminergic neural transmission along mesocortical projections in patients by increasing the precursor availability of L-tyrosine for dopamine biosynthesis. Theoretically, this approach might lessen both negative and positive symptoms of schizophrenia and improve frontal lobe-mediated neuropsychological performance. There was no evidence of statistically significant improvement conferred by L-tyrosine as measured by weekly Brief Psychiatric Rating Scale (BPRS), Schedule for the Assessment of Negative Symptoms (SANS), or Clinical Global Impressions (CGI) scales. The 12-h trough plasma level of L-tyrosine was significantly higher in all patients during the L-tyrosine phase of the study (t = -3.9, df = 20, p = 0.0009). At the end of each 3-week study period, no significant differences could be found in Wisconsin Card Sorting Test (WCST) or memory test performance. Smooth-pursuit eye movement (SPEM) performance had significantly more saccadic intrusions during the L-tyrosine supplementation phase compared to the placebo period. This increase in saccades during SPEM suggests that the tyrosine supplementation might have had some central effect.

Smooth pursuit eye movements in the evaluation of famotidine adjunctive therapy of schizophrenia: a preliminary report.

Smooth pursuit eye movements (SPEM) are often abnormal in schizophrenic patients and have been proposed as a trait marker of the disorder. We explored the use of SPEM as an outcome measure in an open-label clinical trial of famotidine, an H-2 antagonist, in patients with schizophrenia; famotidine has been proposed as an adjunctive medication, particularly for negative symptoms. Prior studies using SPEM as an outcome measure have not found a significant effect with "typical" neuroleptic medication, and one study found greater SPEM dysfunction with clozapine treatment. In this study, 19 schizophrenic subjects were stabilized for at least 1 week on conventional neuroleptic medications and then administered oral famotidine, 100 mg daily, for an additional 3 weeks. SPEM and clinical measures were assessed. Whereas Brief Psychiatric Rating Scale (BPRS) and Schedule for Assessment of Negative Symptoms (SANS) scores decreased significantly with famotidine administration, there was no significant change in SPEM performance over the course of the study. Two subjects (11%) doubled their signal/noise ratio and maintained this increase after famotidine discontinuation, whereas three subjects (17%) approximately halved this ratio and returned to baseline after famotidine discontinuation. SPEM changes were not found to correlate significantly with changes in BPRS or SANS scores. These findings suggest that SPEM dysfunction reflects a "trait" rather than clinical "state" in schizophrenia, and changes in SPEM performance might not be expected always to parallel changes in clinical ratings.

Determination of N-nitrosodimethylamine in environmental aqueous samples by isotope-dilution GC/MS-SIM.

An analytical method for the determination of N-nitrosodimethylamine (N-NDMA) in environmental aqueous samples has been developed using isotope dilution gas chromatography/mass spectrometry in the selected ion monitoring mode (GC/MS-SIM). After deuterated N-nitrosodimethylamine (d6-N-NDMA) as surrogate standard was added to the samples, the analytes were extracted with methylene chloride, dried with anhydrous sodium sulfate, and concentrated in a rotary evaporator. The concentrated extracts were analyzed by GC/MS-SIM after adding N-nitrosodiethylamine as an internal standard. The method detection limit for N-NDMA was 0.003 pg/microL and was validated by an analysis of a fortified water sample. The method was applied to real samples.

Set-covering diagnostic expert system for psychiatric disorders: the third world context.

This paper presents an implementation of the set-covering model for diagnosing psychiatric disorders. Such a model is useful as the basis for the inference mechanism of an expert system in that it provides a satisfactory solution to the difficult problem of multiple simultaneous disorders. The set covers have been formed through the 'diagonal search method' in which the combination of an element with the rest of the elements along the diagonals in the combination matrix was found to be adequate. 'Abductive logic' has been used to reach the possible final solution. Another feature of this expert system is its elicitation system. Provision has been made in the expert system for observations to be made and questions to be asked of the patient in difficult-to-elicit psychiatric signs. It makes this expert system usable by the non-expert clinicians. This has been specially designed in the context of third-world conditions. The system has been tested on cases given in the DSM-III case book with 100% success. However, the system's knowledge should be expanded and refined if it is to be used in psychiatric clinical practice.

Increased cortical excitability with longer duration of Parkinson's disease as evaluated by transcranial magnetic stimulation.

Transcranial Magnetic Stimulation (TMS) was used to evaluate the cortical excitability and central motor pathways in Parkinson's disease (PD) and correlate with severity and duration of disease. 19 cases of PD and 13 controls were enrolled. The threshold intensity (TI), cortical latency (CL), central conduction time (CCT), motor evoked potential amplitude (MEP) obtained with TMS were correlated with Hoehn and Yahr and duration of disease. The threshold intensity (TI) was significantly lower in patients of PD than controls. The TI in patients with PD was 53.16-/+8.4% patients and 67.1-/+21.6% in controls (p<0.05). This strongly correlated with duration of disease, TI being lower in patients with disease duration more than 5 years. There was no difference in the other TMS parameters - CL, CCT, MEP between patients and controls. Our study revealed increased excitability in PD which was related to longer duration of disease.

Falciparum malaria--present day problems. An experience with 425 cases.

Clinical details and present day problems encountered in 425 cases of falciparum malaria (PF) are reported. 10.11% had taken chloroquine prior to reporting to us. Parasitic count done in 23.05% cases lacked correlation with severity of disease. Pattern of fever varied markedly but 5.4% were afebrile throughout and presented only with bodyache and malaise. Apyrexial spell was noted in 5.64%. 28.70% had typical facial looks of anaemia and sallow complexion. Cerebral symptoms were noted in 3.05%. Other symptoms were severe headache 33.4%, pain abdomen 3.29%, gastroenteritis 5.64%, jaundice 2.58% and bronchitis in 7.50%. We encountered subconjunctival haemorrhages with purpura and/or urticaria in four cases, symptoms suggestive of shock lung in 3, pulmonary oedema in 2, severe anaemia (HB less than 4 g%) in seven pregnant ladies, extrapyramidal symptoms in follow up period in 5 and congenital malaria in 2 cases. 83.25% were cured with chloroquine and oxytetracycline. 8.47% (who deteriorated despite the above treatment) were treated with quinine for 6 days. 5.17% (with severe disease) were also given quinine as first line drug. 2.82% (unresponsive to chloroquine and oxytetracycline but with mild disease) were treated with pyrimethamine-sulphamezathine combination for 5 days. One case who did not respond to quinine was treated with quinidine. Recrudescence was seen in 3.67% of patients treated with chloroquine and oxytetracycline. There was no case with renal failure, haemolysis due to G6PD deficiency and black water fever. There was only one death (0.23%) in our series. Self-medication, haphazard therapy and the slogan "Fever may be malaria-take chloroquine" can lead to problems in falciparum malaria.

Ranitidine--rifampicin interaction.

Newly diagnosed patients of pulmonary tuberculosis (n = 112) were put on a rifampicin-containing drug regimen. Fifty six patients were also given a placebo tablet twice daily while the other fifty-six were given ranitidine 150 mg twice daily. Gastric pH, gastric emptying time, serum rifampicin levels, urinary total and unchanged rifampicin, serum bilirubin and ALT levels were measured serially. Clinical record of adverse symptoms was maintained. Ranitidine increased the basal as well as post-drug gastric pH without altering the gastric emptying time. Concomitant administration of ranitidine and rifampicin did not alter the absorption, metabolism or excretion of the latter but reduced the frequency of gastrointestinal symptoms.

Eales' disease with neurological manifestations.

Eales' disease is a primary retinal perivasculitis of an undetermined etiology seen predominantly in the Indian subcontinent. However, neurological involvement is rare. We report here a patient of retinal perivasculitis with neurological dysfunction. Our patient is a 39 years male who developed acute diminished vision right eye in March 99, which progressed for four days and remained static. In April 99 he developed acute diminished vision left eye, which progressed to near total blindness in 48 hours. He was undergoing ophthalmic evaluation. Fourty five days later he developed incoordination and weakness left half of body. The examination revealed bilateral retinal perivasculitis with pyramidal signs and left sided cerebellar signs. Investigations revealed an ESR of 40 mm at the end of first hour. His CT head revealed bilateral basal ganglionic infarcts. MRI head revealed enhancing lesions both basal ganglia and right parietal region. Cerebrospinal fluid examination showed xanthochromic fluid with markedly elevated protein and lymphocytic pleocytosis. His workup for connective tissue disorders was negative. He was put on ATT with steroids. Eales' disease is presumed allergy to tuberculoprotein. A trial of ATT with steroids has been tried with varying results. Our patient had bilateral retinal perivasculitis and neurological dysfunction. He had lymphocytic pleocytosis with markedly elevated protein in the CSF.

Need for a national epilepsy control program.

This article briefly outlines the proposed national epilepsy control program. The content of the article is based on four meetings held by invitation of the Ministry of Health. Invitees by ministry - Drs. D. C. Jain, M. Gourie Devi, V. Saxena, S. Jain, P. Satish. Chandra, M. Gupta, K. Bala, V. Puri, K. S. Anand, S. Gulati, S. Johri, P. S. Chandra, M. Behari, K. Radhakrishnan, D. Bachani. Presentations were made by Dr. M. Tripathi.The program will involve all neurologists across the country in teaching and training at state levels and a central monitoring committee.