Maximum Dimension (maximum + dimension)

Distribution by Scientific Domains


Selected Abstracts


Stone artifact scatters in western NSW, Australia: Geomorphic controls on artifact size and distribution

GEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 6 2001
Patricia Fanning
Surface scatters of Aboriginal stone artifacts have been exposed in many parts of inland Australia by accelerated erosion that followed the introduction of pastoralism by European settlers in the 19th century. This paper reports on a set of techniques developed to investigate and quantify the effects of these post-discard disturbance processes in Sturt National Park in northwest NSW, Australia. Backwards, stepwise, linear regression showed the influence of geomorphic parameters such as slope gradient, elevation, landform, and contemporary surface processes on artifact distribution, with artifact maximum dimension as the dependent variable. The results indicate that, even at low gradients, artifact size and slope angle are significantly related, but that the variance in maximum dimension explained by gradient is very low. Similar results were found for the other geomorphic variables. We conclude that artifact movement by surface wash across these surfaces is unlikely to significantly affect artifact distribution. While vertically conflated surface scatters do not preserve "living floors" in a short-term, functional sense, their apparent horizontal integrity allows investigation of the long-term use of place by hunter-gatherer people in the past. Insofar as assemblage integrity is important for assessing site significance in the heritage management industry, our methods provide a means for assessing the degree to which a site has been damaged by water flow. © 2001 John Wiley & Sons, Inc. [source]


Bayesian estimation of hyperparameters for indirect Fourier transformation in small-angle scattering

JOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 6 2000
Steen Hansen
Bayesian analysis is applied to the problem of estimation of hyperparameters, which are necessary for indirect Fourier transformation of small-angle scattering data. The hyperparameters most frequently needed are the overall noise level of the experiment and the maximum dimension of the scatterer. Bayesian methods allow the posterior probability distribution for the hyperparameters to be determined, making it possible to calculate the distance distribution function of interest as the weighted mean of all possible solutions to the indirect transformation problem. Consequently no choice of hyperparameters has to be made. The applicability of the method is demonstrated using simulated as well as real experimental data. [source]


IgG4-related inflammatory aneurysm of the aortic arch

PATHOLOGY INTERNATIONAL, Issue 4 2009
Mitsuaki Ishida
IgG4-related sclerosing disease can occur in the cardiovascular system and some inflammatory abdominal aortic aneurysms have been shown to belong to IgG4-related sclerosing disease. Herein is reported a case of IgG4-related inflammatory aortic aneurysm of the aortic arch. A 71-year-old Japanese man was found to have an aneurysm of the aortic arch with maximum dimension of 5.5 cm. The surgically resected aneurysm wall had conspicuous fibrosclerotic changes, dense lymphoplasmacytic infiltration and occasional obliterative phlebitis in the adventitia; the thickness of the adventitia was 6.5 mm. Immunohistochemistry indicated numerous IgG4-positive plasma cell infiltrates; 84% of the IgG-bearing cells were IgG4 positive. The diagnosis of IgG4-related inflammatory aortic aneurysm of the aortic arch was made. Although previously reported IgG4-related inflammatory aortic aneurysms were confined to the abdominal aorta, the present case report demonstrates that IgG4-related inflammatory aortic aneurysm can occur in the aortic arch, thereby extending the spectrum of IgG4-related periaortitis. Further studies are needed to clarify the spectrum of IgG4-related sclerosing disease in the cardiovascular system. [source]


Transanal endoscopic microsurgery is a safe and reliable technique even for complex rectal lesions

BRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 7 2008
R. J. Darwood
Background: Transanal endoscopic microsurgery (TEM) is a minimally invasive technique for the excision of rectal lesions, with lower morbidity and mortality rates than open surgery. Following advances in laparoscopic colorectal surgery and endoscopic mucosal resection, this study evaluated the safety and efficacy of TEM in the treatment of complex rectal lesions. Methods: All patients were entered into a prospective database. Complex lesions were identified as high (more than 15 cm from anorectal margin), large (maximum dimension over 8 cm), involving two or more rectal quadrants, or recurrent. Results: Seventy-one lesions (13 carcinomas and 58 tubulovillous adenomas) were identified. The median duration of operation was 60 (interquartile range (i.q.r.) 30,80) min, with an estimated median blood loss of 0 (i.q.r. 0,10) ml. Median hospital stay was 2 (i.q.r. 1,3) days. One patient developed postoperative urinary retention and one returned with rectal bleeding that did not require further surgery. Two patients developed rectal strictures after operation that were dilated successfully. There was no recurrence of benign lesions during a median follow-up of 21 (i.q.r. 6·5,35) months. Conclusion: TEM is a safe technique with low associated morbidity, even when used to excise complex rectal lesions. As such it remains the treatment of choice for rectal lesions not requiring primary radical resection. Copyright © 2008 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd. [source]


Preoperative radiation therapy with selective dose escalation to the margin at risk for retroperitoneal sarcoma

CANCER, Issue 2 2006
Ching-Wei D. Tzeng MD
Abstract BACKGROUND Retroperitoneal sarcomas (RPSs) are rare tumors with poor survival rates due to difficult resectability and high local and distant recurrence rates. Preoperative radiation therapy appears to have dosimetric advantages to utilize the tumor as a tissue expander to limit exposure of small bowel to higher radiation doses. METHODS Between June 1999 and December 2003, 16 consecutive patients with biopsy-proven RPS were treated with preoperative radiation with selective dose escalation. This included 45 grays (Gy) in 25 fractions to the entire tumor plus margin and a boost dose of 57.5 Gy to the volume predicted as high risk for positive surgical margins. Treatment toxicity and local control were evaluated prospectively as primary endpoints. The secondary goal was the theoretical calculation of future dose escalation and feasibility. Each patient underwent laparotomy. Tumor response was judged using computed tomography (CT) scan and by necrosis on final pathology. Theoretical treatment plans evaluated the potential for additional radiation dose escalation. RESULTS All patients completed the radiation protocol. The most common acute side effects were nausea/vomiting, which affected 4 patients (25%), with only 1 patient requiring inpatient intravenous hydration. There was no severe late postoperative morbidity or mortality. Twelve tumors (75%) decreased in maximum dimension, with a median decrease of 9.4%. Fourteen of 16 patients (88%) underwent complete macroscopic resection. With a median follow-up of 28 months (range, 7-52 months), there were only 2 local recurrences. The actuarial 2-year local control rate was 80%. Theoretical treatment plans suggest that significant dose escalation (up to 80 Gy) may be possible. CONCLUSIONS Preoperative radiation therapy with selective dose escalation to the margin at risk is tolerable and allows higher radiation dose to the volume judged to be at greatest risk for local tumor recurrence. Cancer 2006. © 2006 American Cancer Society. [source]