High efficiency, high power 808nm laser array and stacked arrays optimized for elevated temperature operation

Operation of 808-nm laser diode pumping at elevated temperature is crucial to many applications. Reliable operation at high power is limited by high thermal load and low catastrophic optical mirror damage (COMD) threshold at elevated temperature range. We demonstrated high efficiency and high power operation at elevated temperature with high COMD power. These results were achieved through device design optimization such as growth conditions, doping profile, and materials composition of the quantum-well and other layers. Electrical-to-optical efficiency as high as 62% was obtained through lowered threshold current, lowered series resistance and increased slope efficiency. The performance of single broad-area laser diodes scales to that of high power single bars on water-cooled copper micro-channel heatsinks or eonductively-cooled CS heatsinks. No reduction in bar performance or significant spectral broadening is seen when these micro-channel coolers are assembled into 6-bar and 18-bar CW stacks for the h     

1H-nuclear magnetic resonance studies of human synovial fluid in arthritic disease states as an aid to confirming metabolic activity in the synovial cavity

1. A 1H-n.m.r. method was used to measure concentrations of valine, alanine, lactate, acetate, hyaluronan and lipids in synovial fluid obtained, during the normal course of examination from the knee joints of patients attending rheumatology and orthopaedic clinics. Fluid was available from 16 patients with osteoarthritis, 18 patients with rheumatoid arthritis, four patients with meniscal tear and one patient each with systemic lupus erythematosis, mono-arthritis, synovitis and loose bodies. Four normal specimens were obtained for comparison. 2. Valine, alanine and acetate levels all showed a normal Gaussian distribution, reflecting the distributions within the serum of the sample population. 3. Lactate concentrations divided into two distinct patterns. At concentrations below 2.5 mmol/l the lactate levels showed a Gaussian distribution, reflecting the distribution in normal serum. The normal synovial fluid specimens belong to this distribution. Above 2.5-3.0 mmol/l, lactate levels were asymmetric in distribution with a long tail at higher concentrations. These high levels of lactate can be explained by the generation of lactate through anaerobic metabolism within the synovial cavity. This metabolic process is triggered by a general inflammatory condition such as in rheumatoid arthritis. 4. The distribution of n.m.r.-observable lipid concentrations in rheumatoid arthritis and osteoarthritis each shows a normal distribution and the mean concentration is significantly higher in rheumatoid arthritis. 5. An increased n.m.r.-observable hyaluronan concentration is associated with an inflammatory situation. 6. It is concluded that raised levels of lactate and n.m.r.-observable hyaluronan and lipids are useful markers to aid the clinical distinction between rheumatoid arthritis and osteoarthritis.(ABSTRACT TRUNCATED AT 250 WORDS)     

Integration and interference in the cerebral hemispheres: relations with hemispheric specialization

The two hemispheres of the brain often perform complementary computations and make unique contributions to task performance. This study examines the interaction of linguistic (left hemisphere) and prosodic (right hemisphere) information in speech processing. An individual differences approach is used in which interference between linguistic and prosodic processes in a Stroop-like task is compared between individuals who process the two dimensions in opposite hemispheres (complementary specialization) vs. those who process both dimensions in the same hemisphere (noncomplementary specialization). Complementarity was not related to interference in any way. This finding is consistent with the hypothesis of Chiarello and Maxfield (1996) that interference is equivalent between and within hemispheres when it arises in a response selection stage.     

Randomised controlled trial of effects of early discharge after surgery for breast cancer

OBJECTIVE: To determine the effect of early discharge from hospital after surgery for breast cancer on physical and psychological illness. DESIGN: Randomised controlled trial comparing discharge two days after surgery (before removal of drain) with standard management (discharge after removal of drain). SETTING: Regional breast unit. SUBJECTS: 100 women with early breast cancer undergoing mastectomy and axillary node clearance (20) or breast conservation surgery (80). MAIN OUTCOME MEASURES: Physical illness (infection, seroma formation, shoulder movement) and psychological illness (checklist of concerns, Rotterdam symptom questionnaire, hospital anxiety and depression scale) preoperatively and at one month and three months postoperatively. RESULTS: Women discharged early had greater shoulder movement (odds ratio 0.28 (95% confidence interval 0.08 to 0.95); P = 0.042) and less wound pain (odds ratio 0.28 (0.10 to 0.79); P = 0.016) three months after surgery compared with women given standard management. One month after surgery scores were significantly lower on the Rotterdam symptom questionnaire in patients who were discharged early (ratio of geometric mean scores 0.73 (0.55 to 0.98) P = 0.035), but rates of psychological illness generally did not differ between groups. CONCLUSIONS: Increased rates of physical or psychological illness did not result from early discharge after surgery for breast cancer. This policy can be recommended for patients with support at home.     

Randomized phase II study of two schedules of topotecan in previously treated patients with ovarian cancer: a National Cancer Institute of Canada Clinical Trials Group study

PURPOSE: As topotecan is S-phase-specific, its efficacy is likely schedule-dependent. Therefore, a randomized study using a "pick the winner" design was undertaken to compare two schedules in patients with recurrent ovarian cancer. PATIENTS AND METHODS: Patients with recurrent epithelial ovarian cancer previously treated with no more than two separate regimens of chemotherapy, one of which had to be platinum-containing, were randomized to either topotecan 1.5 mg/m2 intravenously (i.v.) over 30 minutes daily for 5 days repeated every 21 days (arm A, the standard arm), or topotecan 1.75 mg/m2 as a 24-hour infusion once a week for 4 weeks repeated every 6 weeks (arm B, the experimental arm). RESULTS: Sixty-six patients were eligible and 63 were assessable for response. The response rate in arm A was 22.6% (95% confidence interval [CI], 9.6% to 41.2%), which was significantly superior to that in arm B, 3.1% (95% CI, 0.1% to 16%) (P = .026). The regimens were not equitoxic, with 94% of patients on arm A experiencing grade 3 or 4 granulocytopenia as opposed to 52% on arm B. CONCLUSION: The weekly 24 hour infusion of topotecan at 1.75 mg/m2 was ineffective in relapsed ovarian cancer. The daily-times-five schedule remains the schedule of choice. As the regimens were not equitoxic, one cannot differentiate between an ineffective schedule and an ineffective dose as the reason for the differing response rates. However, the degree of myelotoxicity that already occurs will preclude any substantially higher dosing with the weekly regimen.     

User Resistance to Information System Implementations: A Dual-Mode Processing Perspective

This article examines the attitudes that can cause users to resist information system implementations using an established theory from social and cognitive psychology: the Elaboration Likelihood Model. It is argued that users who do not think deeply about systems represent a key blockage and that their attitudes are based largely on heuristics and peripheral influences. The results of a wide-ranging study are presented in which 28 heuristics and peripheral influences that commonly affect user attitudes are identified.     

The relation of sulphonated compounds to the textile industry

Conclusion From the foregoing, it is right easily seen that the sulphonated compounds have a close relation to the textile industry, especially that section which deals with scouring, dyeing, mercerizing, printing and finishing of yarns and fabrics. A Paper Delivered Before the 8th Fall Meeting—A.O.C.S.     

Semantic ambiguity resolution in positive schizotypy: A right hemisphere interpretation.

Positive schizotypal traits have been associated with right hemisphere activation. Previous research has indicated that the left and right hemispheres differ in their processing of semantic ambiguity; specifically, given sufficient time, the left hemisphere primes dominant meanings and inhibits subordinate meanings, and the right hemisphere primes both dominant and subordinate meanings. The authors examined whether individuals who differed in positive schizotypy demonstrated different patterns of priming on a semantic ambiguity task, reflective of differences in hemispheric activation. Individuals low in schizotypy demonstrated the expected pattern of priming the dominant meaning while inhibiting the subordinate meaning. Individuals high in schizotypy demonstrated similar priming of the dominant meaning but no inhibition of the subordinate meaning. The role of this failure of inhibition in the generation of schizotypal thought is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Wide area computing: resource sharing on a large scale

Consider almost any computing resource today-whether hardware, software, or data-and it will invariably be networked. Computing over wide area networks has been largely ad hoc, but as needs increase, piecemeal solutions no longer make sense. The authors set out to design and build a wide-area operating system that would allow multiple organizations with diverse platforms to share and combine their resources. This system, Legion, is a network-level operating system designed from scratch to target wide-area computing demands     

Hamiltonian formulation for solitary waves propagating on a variable background

Solitary waves propagating on a variable background are conventionally described by the variable-coefficient Korteweg-de Vries equation. However, the underlying physical system is often Hamiltonian, with a conserved energy functional. Recent studies for water waves and interfacial waves have shown that an alternative approach to deriving an appropriate evolution equation, which asymptotically approximates the Hamiltonian, leads to an alternative variable-coefficient Korteweg-de Vries equation, which conserves the underlying Hamiltonian structure more explicitly. This paper examines the relationship between these two evolution equations, which are asymptotically equivalent, by first discussing the conservation laws for each equation, and then constructing asymptotically a slowly-varying solitary wave.