Haemolytic activity of Aeromonas species isolated in Libya

Twenty seven Aeromonas strains (5A. hydrophila, 8A. sobria and 14A. caviae) isolated from children with diarrhoea and 34 Aeromonas strains (9A. hydrophila, 7A. sobria an 18A. caviae) isolated from children without diarrhoea were tested from haemolysin production. The results obtained showed that haemolysin production using human, horse or sheep erythrocytes was significantly associated with A.hydrophila and A sobria but not with A.caviae, regardless of whether these strains were isolated from children with or without diarrhoea. Human or horse rather than sheep erythrocytes are recommended for use in the haemolysin assay.     

Supporting real-time and multimedia applications on the Mercuritestbed

This paper describes the distributed system, network and software architecture, the application development environment, the performance, and the early lessons learned on the ATM LAN testbed Mercuri established at the Honeywell Technology Center, to develop distributed multimedia technologies for real-time control applications. We have developed a client-server-based software architecture on Sun Sparcstation-2s connected by a Fore Systems' ASX-100 ATM switch, with video processing handled by Parallax's X Video cards. The architecture enables network-transparent applications and provides simple primitives for multimedia capture, display, transmission, storage, and retrieval. A real-time multimedia-in-the-loop control application was developed as the vehicle for testing the capabilities and performance of the network. Our test measurements focus on the end-user-level performance metrics such as message throughput and round-trip delay as well as video-frame jitter under no-load and load conditions. Our results show that the maximum burst throughput that can be supported at the user level is 48 Mb/s using AAL 5, while round-trip delays for 4-kbyte messages are about 3 ms. Our experience reveals a number of performance bottlenecks and open issues in using commercial ATM switches for practical applications. Our conclusions are outlined     

Arthroscopic replacement of the anterior cruciate ligament with a double semitendinosus tendon

At the university hospital of emergency surgery in Innsburck and at the emergency services department of the hospital in Schwaz, anterior cruciate ligament reconstruction was performed in 467 patients between January 1992 and September 1993. In 117 cases, a double semitendinous tendon was used as an autograft. A total of 60 of these patients were followed up at an average of 20 months (13-33) after reconstruction. The results were rated according to the OAK and the Tegner scores. Objective measurements of instability were carried out by a KT 1000 arthrometer. In addition, 21 patients underwent computer-interfaced dynamometer testing using a Cybex 6000. Standardized loading of the thigh muscles was performed at angular velocities of 60 degrees/s (3 repetitions) and 240 degrees/s (30 repetitions): peak torques and total work were analyzed. The mean age was 23.5 years (17-55): 48 were male, 21 female. The main reasons for the ACL ruptures were sports injuries (51 cases). The patients were classified into three groups according to the data of the repair (group 1 reconstruction up to 1 week after trauma-28 patients: group 2: reconstruction between the 2nd and 6th week after trauma-15 patients: group 3: reconstruction 6 and more weeks after trauma-26 patients). In group 1. additional ruptures of the menisci. lesions of the MCL. and chondromalacia were seen in 71.4%. in group 2 in 73.3% and in group 3 in 80.8%. The average rating in the OAK score was 90.16 points: 38 patients (55.70%) had excellent results. 18(26.09%) were good. 9(13.04%) were fair and 4(5.80%) were poor. The Tegner activity score showed a reduction of 0.36 points on average. The largest amount of anterior translation was performed with the KT 1000 manual drawer test (2.29 mm on average compared with the contralateral side). Dynamometer testing showed a statistically significant difference in flexor and extensor mechanism (compared with the non-involved side) in both peak torques and total work. A repeat arthroscopy became necessary in five cases: arthrofibrosis in three and incipient joint infection in two cases.     

Human papillomavirus-specific serologic response in vulvar neoplasia

We describe a case of positional dyspnea due to compression of the tracheobronchial tree by an extensive thoracic aneurysm. In a 77-year-old woman with long-standing systemic hypertension, intermittent anterior chest pain gradually developed over several years. She had no history of asthma or thoracic trauma. She was admitted to our hospital because of sudden, severe shortness of breath. The breathlessness was markedly worse when she lay on her back or on her right side. On physical examination, she was in acute respiratory distress with cyanosis, severe hypertension (180/110 mmHg), tachycardia, and inspiratory stridor. A chest X-ray film showed loss of volume and nearly complete radiopacity of the left hemithorax. Arterial blood gas analysis revealed an arterial oxygen partial pressure of 54.8 mmHg, a carbon dioxide partial pressure of 39.8 mmHg, and an oxygen saturation of 84.5 percent on room air. Computed tomographic examination of the thorax showed dilation of the aortic arch and descending aorta, and marked compression of the trachea and the left main bronchus. Examination with a fiberoptic bronchoscope revealed extrinsic compression of the trachea just proximal to the carina. The patient's symptoms stabilized. However, she did not undergo surgery because of her age and because of the size of the aneurysm. She died due to rupture of the aneurysm.     

Use of exercise technetium-99m sestamibi SPECT imaging to detect residual ischemia and for risk stratification after acute myocardial infarction

The clinical presentation, electrocardiographic findings, and technetium-99m sestamibi single-photon emission computed tomography (SPECT) imaging results of 134 consecutive patients who underwent nuclear exercise testing within 14 days of an acute myocardial infarction (AMI) were correlated with cardiac events over a 15 +/- 10-month follow-up. Whereas only 23 patients (17%) had chest pain and 31 (23%) had ischemic ST-segment depression during exercise, 94 (70%) had ischemia on SPECT (p < 0.001). On follow-up, 13 patients experienced a cardiac event: 7 were rehospitalized for unstable angina, 3 had recurrent AMI, and 3 died of cardiac causes. Ischemia on the sestamibi images identified 11 of these patients (85%), whereas chest pain identified only 3 (23%, p = 0.006), and electrocardiographic ischemia identified only 4 (31%, p = 0.017). The presence of either ischemia as seen on SPECT or defects in multiple vascular territories identified 12 patients (92%) with an event, including all who had cardiac death. By Cox regression analysis of clinical, stress, and image parameters, the number of ischemic defects on SPECT was the only significant correlate of a future event (chi-square = 4.62, p = 0.03), and patients with > or = 3 reversible sestamibi defects had an event rate of 38%. The extent of ischemia as seen on nuclear imaging remained a strong correlate (p = 0.008) of an event in the 54 patients (40%) who had received thrombolytic therapy. Thus, exercise technetium-99m sestamibi SPECT after AMI frequently reveals residual ischemia, and is better than clinical data, symptoms, and stress electrocardiographic data in identifying patients who will have a subsequent cardiac event.     

Stress-voiding in tungsten-plug interconnect systems induced byhigh-temperature processing

We describe the sensitivity of sub-micron via integrity to high-temperature processing following via etch. It has been observed that thermal expansion of Al into the via hole, before tungsten deposition, may result in the fabrication of a deformed tungsten plug. Our results indicate that relaxation of the Al can give rise to stress-void formation under the tungsten plug. This may manifest itself either during electromigration stress or high-temperature storage. This mechanism represents a new reliability hazard for a tungsten-plug interconnect system     

A methodology for the performance evaluation of data querystrategies in universal mobile telecommunication systems (UMTS)

The anticipated emergence of third-generation mobile systems, referred to as universal mobile telecommunication systems (UMTS), raises the problem of reconsidering the design of the databases destined to contain the user information. In particular, it is expected that the key concepts of the new database architectures will be high distribution and fast updating of information. So far, the problem of determining the most appropriate distributed database (DDB) architectures for third-generation mobile systems has not been widely dealt with in literature. This paper presents a methodology for evaluating hierarchical DDB architectures by means of an analytical model of the data querying operation. This methodology allows for structural alternatives, differing on account of the number of levels and branches in the hierarchy, to be evaluated in terms of query loads and mean response times, according to a given user mobility characterization and a given search protocol operation. By way of illustration, the paper discusses a case study, concerning a query operation arising from a location updating procedure and applied to a hierarchical tree-like DDB in which some structural alternatives are considered