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D P Lawrence

Publications and source records attributed to D P Lawrence.

9 recordsLinked to original sources
PubMed2002

MBR-technology in municipal wastewater treatment: challenging the traditional treatment technologies.

In The Netherlands a development programme for the application of the MBR technology in municipal wastewater treatment has started. This paper briefly describes this development programme and goes into detail for the first step: a large pilot plant study at the Beverwijk WWTP. Under the supervision of DHV Water four different membrane systems from Kubota, Mitsubishi, X-Flow and Zenon were extensively tested. The objectives set for the study were more than achieved. The available world knowledge regarding municipal MBR was extremely limited and often very specific for a particular country's wastewater and wastewater flow characteristic. The conditions set by the Dutch situation were the first of its kind and lead to new methods of MBR optimisation. After almost two years of intensive research and further development of the technological feasibility of the MBR for The Netherlands, it has been decided to extend it to demonstration scale.

Bioreactors↗
PubMed2000

A phase II pilot trial of concurrent biochemotherapy with cisplatin, vinblastine, dacarbazine, interleukin 2, and interferon alpha-2B in patients with metastatic melanoma.

In an effort to develop a biochemotherapy regimen for metastatic melanoma suitable for testing in a cooperative group setting, we modified the concurrent biochemotherapy regimen of S. S. Legha et al. (J. Clin. Oncol., 16: 1752-1759, 1998) by providing enhanced supportive care and developing a strict, conservative approach to the management of treatment-related toxicities. Patients received cisplatin, vinblastine, and dacarbazine (CVD: cisplatin (20 mg/m2) and vinblastine (1.2 mg/m2) on days 1-4, dacarbazine (800 mg/m2) on day 1 only) concurrently with interleukin 2 (9 MIU/m2/day) by continuous i.v. infusion on days 1-4 and IFN-alpha (5 MU/m2/day) on days 1-5, 8, 10, and 12. Prophylactic antibiotics and a maximum of four cycles were administered. Routine granulocyte colony-stimulating factor and aggressive antiemetics were initiated after patients 7 and 14, respectively. Forty-four patients were enrolled in this study. No patients had received prior chemotherapy or interleukin 2; however, 23 (53%) had received prior IFN-alpha, mostly in the adjuvant setting. A total of 131 treatment cycles was administered. Significant toxicities requiring dose modification included: hypotension requiring pressors (15 episodes in 11 patients), grades 3/4 vomiting (12 episodes in 15 cycles; 5 episodes in 12 patients (6 episodes in 9 cycles after initiation of the modified antiemetic regimen), transient renal insufficiency (5 episodes in 5 patients), grade 4 thrombocytopenia (24 episodes, 1 associated with bleeding), neutropenia with or without fever (15 instances, only 11 in 112 cycles after routine use of granulocyte colony-stimulating factor), and catheter-related bacteremia (2 patients). Five (16%) of 30 patients who were treated after the last protocol modification experienced what we defined as unacceptable toxicity for a cooperative group setting. Responses were seen in 19 of 40 evaluable patients (relative risk, 48%) with 8 complete responses (20%). The median response duration was 7 months (range, 1-17+ months) with one currently ongoing. The central nervous system was the initial site of relapse in 11 responding patients. The median survival duration was 11 months (range, 2-31 months). This modified, concurrent biochemotherapy regimen is active and tolerable for use in a cooperative group setting. Central nervous system relapse, however, remains a concern for responders. This regimen is being compared with CVD in a Phase III Intergroup Trial (Eastern Cooperative Oncology Group/Southwest Oncology Group 3695).

Adult↗
PubMed1999

Benchmark testing the Digital Imaging Network-Picture Archiving and Communications System proposal of the Department of Defense.

The Department of Defense issued a Request for Proposal (RFP) for its next generation Picture Archiving and Communications System in January of 1997. The RFP was titled Digital Imaging Network-Picture Archiving and Communications System (DIN-PACS). Benchmark testing of the proposed vendors' systems occurred during the summer of 1997. This article highlights the methods for test material and test system organization, the major areas tested, and conduct of actual testing. Department of Defense and contract personnel wrote test procedures for benchmark testing based on the important features of the DIN-PACS Request for Proposal. Identical testing was performed with each vendor's system. The Digital Imaging and Communications in Medicine (DICOM) standard images used for the Benchmark Testing included all modalities. The images were verified as being DICOM standard compliant by the Mallinckrodt Institute of Radiology, Electronic Radiology Laboratory. The Johns Hopkins University Applied Physics Laboratory prepared the Unix-based server for the DICOM images and operated it during testing. The server was loaded with the images and shipped to each vendor's facility for on-site testing. The Defense Supply Center, Philadelphia (DSCP), the Department of Defense agency managing the DIN-PACS contract, provided representatives at each vendor site to ensure all tests were performed equitably and without bias. Each vendor's system was evaluated in the following nine major areas: DICOM Compliance; System Storage and Archive of Images; Network Performance; Workstation Performance; Radiology Information System Performance; Composite Health Care System/Health Level 7 communications standard Interface Performance; Teleradiology Performance; Quality Control; and Failover Functionality. These major sections were subdivided into workable test procedures and were then scored. A combined score for each section was compiled from this data. The names of the involved vendors and the scoring for each is contract sensitive and therefore can not be discussed. All of the vendors that underwent the benchmark testing did well. There was no one vendor that was markedly superior or inferior. There was a typical bell shaped curve of abilities. Each vendor had their own strong points and weaknesses. A standardized benchmark protocol and testing system for PACS architectures would be of great value to all agencies planning to purchase a PACS. This added information would assure the purchased system meets the needed functional requirements as outlined by the purchasers PACS Request for Proposal.

Benchmarking↗
PubMed1992

Aortic dissection in acute pancreatitis.

Extrapancreatic fluid collections are frequently seen in acute pancreatitis. Vascular damage with life-threatening hemorrhage is also a known complication. In the case report presented, we include documentation by computed tomography of an apparent abdominal aortic wall dissection by fluid in a patient with acute pancreatitis. Conservative therapy resulted in complete resolution without hemorrhage or aneurysm formation.

Acute Disease↗
PubMed1991

Cholecystokinin enhanced hepatobiliary scanning with ejection fraction calculation as an indicator of disease of the gallbladder.

Chronic acalculous cholecystitis represents 5 to 20 per cent of electively treated diseases of the gallbladder. A 70 per cent success rate in relieving these patients of chronic pain was reported when surgical treatment was recommended based on symptoms alone. The cholecystokinin ejection fraction, which is a quantitative measure of emptying of the gallbladder, was 95 per cent accurate in predicting which patients would be relieved of symptoms by surgical treatment. In this study, we report our consecutive experience during a 20 month period with 83 patients.

Adult↗
PubMed1990

Rhabdomyosarcoma of the testicular appendage in an infant: case report.

This is a case report of embryonal rhabdomyosarcoma of the epididymal appendage in a 15-month old infant. It is a rare tumor with a good prognosis when treated promptly. The ultrasound examination showed the testicle to be enlarged but hypo-echoic in comparison to the epididymis which was infiltrated with tumor. An inflammatory mass or enlargement of a testicle demands careful diagnosis and appropriate therapy with immediate referral to a urologist if the normal clinical course deviates. Representative images are included. Rhabdomyosarcoma of the testicle or extra testicular scrotal structures is rare. A report in 1983 by Kage et al from Japan revealed two cases of the tumor, however, both were in adult males. This case report is an embryonal rhabdomyosarcoma in a fifteen month old infant which presented with a confusing clinical picture. This case is presented in an effort to alert the clinician to the possibility of a rare, non-germ cell tumor presenting as an inflammatory lesion.

Epididymis↗
PubMed1987

NMR studies of backbone-alkylated DNA: duplex stability, absolute stereochemistry, and chemical shift anomalies of prototypal isopropyl phosphotriester modified octanucleotides, (Rp,Rp)- and (Sp,Sp)-(d-[GGA(iPr)ATTCC])2 and -(d-[GGAA(iPr)TTCC])2.

The DNA octamer (d-[GGAATTCC])2 and four alkylated analogues, (Rp)-(d-[GGA(iPr)ATTCC])2, (Sp)-(d-[GGA(iPr)ATTCC])2, (Rp)-(d-[GGAA(iPr)TTCC])2, and (Sp)-(d-[GGAA(iPr)TTCC])2 have been examined using 1H and 31PNMR spectroscopies. Duplex stability, as monitored by both NMR and optical measurements, is shown to be a function of both site and stereochemistry of the phosphotriester moiety. Chemical shift changes relative to the native octamer indicate that there are long-range perturbations in the isopropylated molecules. 1HNMR is shown to be a general means by which stereochemistry at phosphorous can be determined.

Alkylating Agents↗
PubMedDate not supplied

Case report. Inflammatory pseudotumor in the retrorectal space: CT and MR appearance.

We report a case of an inflammatory pseudotumor of the retrorectal space, with CT and MRI findings. The imaging findings in this case are consistent with those reported from other anatomic sites, demonstrating the aggressive nature of this histologically benign but frequently invasive mass. Recent discussions in the literature advise close imaging follow-up after surgical excision, particularly in cases in which incomplete resection is deemed preferable to a more mutilating radical resection.

Female↗