A preliminary investigation of natural gas combustion as applied to thermal recovery of petroleum

Present application of the subsurface combustion processes in the thermal recovery of petroleum afford favorable and opportune methods of providing greater recoveries from petroleum reservoirs. This study attempts to elucidate some of the parameters controlling the complex hydrocarbon oxidation for one such process. The experimental phase consisted of investigating the combustion behavior of eight nonexplosive and one explosive natural gas-air mixtures at low and intermediate pressures. The hydrocarbon was allowed to oxidize by self-ignition under controlled conditions within environments precluding a visible flame type reaction. Progress of the reaction was followed by measuring effluent oxygen content. Experimental evidence indicate the combustion reactions were inhibited by packing and varying degrees of reaction completion could be obtained through variation of controlling parameters. Effects of increasing reactor pressure permitted a lower oxidation temperature. Initial oxidation temperatures were found to vary from 950 °F at atmospheric pressure to approximately 470 °F at 27.65 atmospheres absolute pressure. Although data obtained experimentally are not sufficient to permit a rigorous interpretation, nevertheless a qualitative interpretation of parameters controlling natural gas combustion in a porous now system has been presented --Introduction, page vi

Continuous infusion of low-dose 5-fluorouracil and radiation therapy for poor-prognosis squamous cell carcinoma of the uterine cervix

Ten patients with squamous cell carcinoma of the cervix metastatic to periaortic lymph nodes were treated with external-beam radiation therapy and synchronous infusion of intravenous 5-fluorouracil (5-FU) chemotherapy at doses of 350 mg/m2/day. The overall response rate was 90% with four complete responses (CR) and five partial responses (PR). The median duration of response was 11.8 months for CRs and 3.6 months for PRs. Toxicity was tolerable, with gastrointestinal symptoms and myelosuppression being noted most frequently. No patient experienced life-threatening toxicity. Median survival was 7.6 months, with only one patient being alive and free of disease at 2 years. In this pilot study we were unable to demonstrate a beneficial effect of continuous infusion of low doses of 5-FU chemotherapy concurrent with radiation therapy when compared to conventional radiotherapy in patients with advanced squamous cell carcinoma of the cervix.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/30181/1/0000566.pd

American Association of Physicists in Medicine Radiation Therapy Committee Task Group 53: Quality assurance for clinical radiotherapy treatment planning

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/134846/1/mp8373.pd

Comparison of conventional and CT-based planning for intracavitary brachytherapy for cervical cancer: target volume coverage and organs at risk doses

<p>Abstract</p> <p>Background</p> <p>To compare intracavitary brachytherapy (ICBT) planning methods for cervical cancer, based on either orthogonal radiographs (conventional plan) or CT sections (CT plan); the comparison focused on target volume coverage and dose volume analysis of organs at risk (OARs), by representing point doses defined by the International Commission on Radiation Units and Measurement (ICRU) and dose volume histograms (DVHs) from 3D planning.</p> <p>Methods</p> <p>We analyzed the dosimetric data for 62 conventional and CT-based ICBT plans. The gross tumor volume (GTV), clinical target volume (CTV) and organs at risk (OAR)s were contoured on the CT-plan. Point A and ICRU 38 rectal and bladder points were defined on reconstructed CT images.</p> <p>Results</p> <p>Patients were categorized on the basis of whether the >95% isodose line of the point-A prescription dose encompassed the CTV (group 1, n = 24) or not (group 2, n = 38). The mean GTV and CTV (8.1 cc and 20.6 cc) were smaller in group 1 than in group 2 (24.7 cc and 48.4 cc) (<it>P <</it>0.001). The mean percentage of GTV and CTV coverage with the 7 Gy isodose was 93.1% and 88.2% for all patients, and decreased with increasing tumor size and stage. The mean D2 and D5 rectum doses were 1.66 and 1.42 times higher than the corresponding ICRU point doses and the mean D2 and D5 bladder doses were 1.51 and 1.28 times higher. The differences between the ICRU dose and the D2 and D5 doses were significantly higher in group 2 than in group 1 for the bladder, but not for the rectum.</p> <p>Conclusion</p> <p>The CT-plan is superior to the conventional plan in target volume coverage and appropriate evaluation of OARs, as the conventional plan overestimates tumor doses and underestimates OAR doses.</p

Brachytherapy for cervix cancer: low-dose rate or high-dose rate brachytherapy – a meta-analysis of clinical trials

<p>Abstract</p> <p>Background</p> <p>The literature supporting high-dose rate brachytherapy (HDR) in the treatment of cervical carcinoma derives primarily from retrospective series. However, controversy still persists regarding the efficacy and safety of HDR brachytherapy compared to low-dose rate (LDR) brachytherapy, in particular, due to inadequate tumor coverage for stage III patients. Whether LDR or HDR brachytherapy produces better results for these patients in terms of survival rate, local control rate and the treatment complications remain controversial.</p> <p>Methods</p> <p>A meta-analysis of RCT was performed comparing LDR to HDR brachytherapy for cervix cancer treated for radiotherapy alone. The MEDLINE, EMBASE, CANCERLIT and Cochrane Library databases, as well as abstracts published in the annual proceedings were systematically searched. We assessed methodological quality for each outcome by grading the quality of evidence using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology. We used "recommend" for strong recommendations, and "suggest" for weak recommendations.</p> <p>Results</p> <p>Pooled results from five randomized trials (2,065 patients) of HDR brachytherapy in cervix cancer showed no significant increase of mortality (p = 0.52), local recurrence (p = 0.68), or late complications (rectal; p = 0.7, bladder; p = 0.95 or small intestine; p = 0.06) rates as compared to LDR brachytherapy. In the subgroup analysis no difference was observed for overall mortality and local recurrence in patients with clinical stages I, II and III. The quality of evidence was low for mortality and local recurrence in patients with clinical stage I, and moderate for other clinical stages.</p> <p>Conclusion</p> <p>Our meta-analysis shows that there are no differences between HDR and LDR for overall survival, local recurrence and late complications for clinical stages I, II and III. By means of the GRADE system, we recommend the use of HDR for all clinical stages of cervix cancer.</p

Separate Ovens

Gives an introduction to the architectural implications of installing ovens that are separate from top-of-the-stove burners

Patent information in a large electrical company, exemplified by the situation at Siemens

The special situation of patent information is dealt with against the background of the general problems of information provision. The role of the Patent Department of Siemens as a user of patent information and in the distribution of patent information within the company is discussed. Finally, the present system of current patent information on granted patents and first publications is outlined and an outlook on future developments given.