Diamagnetic measurements by concentric loops in the HL-2A tokamak.

The diamagnetic concentric loop method in the HL-2A tokamak is described in this article. The system consists of two concentric poloidal loops with different areas enclosing the plasma column and a short time constant differential integrator, RC < 1 ms. The diamagnetic flux in HL-2A ranges from 1 mWb to 2 mWb for typical discharges with plasma current Ip = 100-400 kA. The integrator output ranges from 0.1 V to 0.2 V with time constant RC = 0.5 ms, and differential area ΔS∕Sout ≈ 7%. Using hybrid analog-digital compensation, the integration drift can be well compensated within 5 mV∕10 s, which can meet the requirement of the concentric loop system. In this method, the measurement of differential area ΔS is not required. The vacuum toroidal flux can be compensated by adjusting the resistance in the integration circuit for several discharges with toroidal field only, which minimizes the additional error produced by a measurement of differential area. The diamagnetic concentric loop system improved the signal to noise ratio by using the short time constant integration. The system with a resolution of ±0.2 kJ can be used to study rapid changes in plasma stored energy, such as the additional power absorbed by the plasma, and the energy loss caused by edge localized modes.

Development of high-speed and wide-angle visible observation diagnostics on Experimental Advanced Superconducting Tokamak using catadioptric optics.

A new wide-angle endoscope for visible light observation on the Experimental Advanced Superconducting Tokamak (EAST) has been recently developed. The head section of the optical system is based on a mirror reflection design that is similar to the International Thermonuclear Experimental Reactor-like wide-angle observation diagnostic on the Joint European Torus. However, the optical system design has been simplified and improved. As a result, the global transmittance of the system is as high as 79.6% in the wavelength range from 380 to 780 nm, and the spatial resolution is <5 mm for the full depth of field (4000 mm). The optical system also has a large relative aperture (1:2.4) and can be applied in high-speed camera diagnostics. As an important diagnostic tool, the optical system has been installed on the HT-7 (Hefei Tokamak-7) for its final experimental campaign, and the experiments confirmed that it can be applied to the investigation of transient processes in plasma, such as ELMy eruptions in H-mode, on EAST.

Cervical spinal osteosarcoma in an adolescent.

Primary cervical spine osteosarcoma is rare and is considered to have a poor prognosis. We describe an adolescent patient suffering from primary cervical spine osteosarcoma with delayed diagnosis. Nineteen months deficit and symptom-free survival was achieved after an aggressive multi-modality treatment comprising surgery and adjuvant chemoradiotherapy.

Non-surgical primary treatment of chronic subdural haematoma: Preliminary results of using dexamethasone.

From a series of 112 cases (64 men and 48 women, aged 37 - 91 years) of chronic subdural haematoma (CSDH) in a 2-year period from January 1998 to December 1999, we have prospectively studied a group of 30 patients, who were managed non-operatively: 26 patients were treated with dexamethasone (Group 1) and four patients expectantly (Group 4). Nineteen patients (73%) from Group 1 were confused or had focal neurological deficits on admission. The mean maximum thickness of the CSDH was 12 mm. Only one of these cases (4%) required surgical drainage 6 weeks after steroid therapy. One patient died of an unrelated stroke (mortality = 4%). Two patients (8%) were left severely disabled. No significant complication from steroid therapy was documented. Out of the 85 surgically treated patients, 69 patients underwent surgical drainage in addition to steroid therapy (Group 2). Thirteen patients were treated with burr-hole drainage only (Group 3). The mean maximum thickness of the CSDH for these two groups were both 16 mm. Comparing with group 1, the redrainage rate of Group 2 [4% (3/69, p = 1)] and that of Group 3 [15% (2/13, p = 0.253)] were not significantly different. 50% of patients in Group 4 (2/4, p = 0.039) required delayed surgical drainage. The mortality rates of Groups 2, 3 and 4 were 3% (2/69, p = 1), 15% (2/13, p = 0.253) and 50% (2/4, p = 0.039), respectively. Our results suggest that steroid treatment in a selected group of patients is a good option, particularly in patients with co-morbidity.

Risperidone augmentation of specific serotonin reuptake inhibitors in the treatment of refractory obsessive-compulsive disorder: report of two cases.

The efficacy of specific serotonin reuptake inhibitors (SSRI) in the treatment of obsessive-compulsive disorder (OCD) has been established, but more than 40% of patients continue to have a poor response to SSRI. Low-dose antipsychotic augmentation of SSRI has contributed to the amelioration of symptoms in the treatment of refractory obsessive-compulsive disorder patients. Due to the risk of side effects from traditional antipsychotics, atypical novel antipsychotic augmentation of SSRI may be a good choice in the treatment of refractory obsessive-compulsive disorder. Herein we report our experience with two OCD patients, one with a poor response to fluoxetine 80 mg per day for 3 months, and the other with poor response to fluoxetine 60 mg per day for 3 months. Both OCD patients also proved to have a poor response to paroxetine 60 mg per day for 6 weeks. Neither patient had received any psychotherapy or behavioral therapy. Both patients showed significant improvement in their obsessive-compulsive symptoms as measured by the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS), after risperidone 1 mg per day was added to their on-going use of paroxetine 60 mg per day. Within 4 weeks of adding risperidone, the two patients' Y-BOCS scores had decreased by 57% and 53%. This result suggests that risperidone augmentation of SSRI may be a good choice and an effective treatment strategy for refractory OCD.

Clinical characteristics of outpatients at a psycho-oncology clinic in a radiation oncology department.

BACKGROUND: Psychosocial care in cancer medicine has become increasingly important. The first psychiatric consultation-liaison (C-L) outpatient clinic in Taiwan was established in a department of radiation oncology in a medical center in Oct. 1998. METHODS: From October 1998 through January 2000, 121 patients were referred for psychosocial evaluation. Six referred patients were excluded because of cerebral complications of malignant disease or coincidental psychiatric disorder. The remaining 115 patients were referred because of psychological problems related to their malignant disease. These patients were divided into 'depression related disorder' and 'anxiety related disorder' groups according to psychiatric standard diagnoses. The records of these referred patients were retrospectively analyzed based on the psychiatric diagnoses. RESULTS: The outpatient utilization rate for psychiatric consultation escalated from 0% to 5.92% after the C-L clinic was established. Patients with nasopharynx, breast, and head and neck cancer had higher referral, rates (over 10%) than patients with other types of cancer. There were significant differences in major subjective psychiatric problems and psychological reactions between patients with psychiatric diagnosis and those without psychiatric diagnosis. Cancer patients who were diagnosed with 'depression related disorder' visited this clinic more times than those with 'anxiety related disorder'. The former received antidepressant drugs more frequently than the latter. There were also more multiple visits in the former group than the latter group. CONCLUSION: Locating a C-L clinic in a radiation oncology department improves access to psychiatric evaluation, early detection and continuous intervention can then be offered to cancer patients with anxiety or depression, especially those with 'depression related disorder'.

Concomitant neuroleptic malignant syndrome and lithium intoxication in a patient with bipolar I disorder: case report.

The purpose of this report is to remind clinicians of the risk of the simultaneous occurrence of neuroleptic malignant syndrome (NMS) and lithium intoxication. A 39-year-old female with bipolar I disorder was admitted to our psychiatric ward due to relapse of a manic episode and a suicide attempt in which she had ingested 20 to 30 tablets of lithium (300 mg/tablet) 12 hours before admission. Except for intramuscular injection of 5 mg of haloperidol 30 minutes after admission, the patient received no antipsychotic drugs during her hospitalization. Six hours after admission, she began to show symptoms of NMS. Lithium intoxication was also found. Within a week, her condition had stabilized with no neurological complications or cognitive deficits noted during the following 4 months. Discussed in this case report are the risk factors of NMS found in this patient, drug interactions of lithium and antipsychotic agents as related to NMS, and problems in clinical management.