Regulation of ADAMTS13 by proteolitic enzymes

Imperial Users onl

A Conceptual Model to study the Diffusion of the Internet in Vietnam

This paper discusses the application of structuration theory in understanding the complex Internet innovation phenomenon in a developing country. It provides references to earlier studies on IS innovation and discusses two controversial perspectives on technological determinism and social constructivism. Through a review of existing IS literature on structuration theory a new direction is proposed to investigate one of the 20th century’s major technological innovations, the Internet. A conceptual model and an analytical framework for studying the complex interactions between institutional structures and Internet innovation patterns in developing countries are presented. The most appropriate research methodology to study Internet innovation in Vietnam is articulated and discussed

The Reverse Galeal Hinge Flap: Another Valuable Technique in the Repair of Scalp Defects Extending to the Calvarium

Over the last 30 years, the estimated incidence of nonmelanoma skin cancer (NMSC) has increased from 300,000 to greater than 2 million cases. Approximately 15% of these cancers occur on the scalp.1 Given the increasing incidence of NMSC and their predilection for the scalp, the demand for scalp repairs will continue to rise. It is important that the dermatologic surgeon is equipped to manage these cases, in particular defects that extend to the bone.The repair of large scalp defects extending to the calvarium is especially challenging for several reasons. The primary closure of any large scalp wound is complicated by the relative inelasticity of scalp tissue and the convexity of the scalp. Rotation flaps are the mainstay technique of re-approximating large scalp wounds but are often unable to completely close very large defects.2 Skin grafts can also be used to cover wounds primarily or in conjunction with other closure techniques.2 However, when scalp defects extend to the bone, the poor vascularity of the osseous tissue severely limits both skin grafting and xenografting. Various approaches to making exposed bone more suitable for grafting have been described in the recent literature, and these techniques and their limitations will be briefly discussed.3–5 The authors will also present two cases that outline a simple method of re-establishing a vascular bed on exposed bone using a reverse galeal hinge flap

Spatial sound and sound localization on a horizontal surface for use with interactive surface (tabletop) computers

Tabletop computers (also known as surface computers, smart tables, and interactive surface computers) have been growing in popularity for the last decade and are poised to make in-roads into the consumer market, opening up a new market for the games industry. However, before tabletop computers become widely accepted, there are open problems that must be addressed with respect to audio interaction including: "What loudspeaker constellations are appropriate for tabletop computers?" "How does our perception of spatial sound change with these different loudspeaker configurations?" and "What panning methods should be used to maximally use the spatial localization abilities of the user(s)?" Using a custom-built tabletop computer setup, the work presented in this thesis investigated these three questions/problems via a series of experiments. The results of these experiments indicated that accurately localizing a virtual sound source on a horizontal surface is a difficult and error-prone task, for all of the methods that were used

Difference in real-time magnetic image analysis of colonic looping patterns between males and females undergoing diagnostic colonoscopy.

Abstract Background and study aim Magnetic imaging technology is of proven benefit to trainees in colonoscopy, but few studies have examined its benefits in experienced hands. There is evidence that colonoscopy is more difficult in women. We set out to investigate (i) associations between the looping configurations in the proximal and distal colon and (ii) differences in the looping prevalence between the sexes. We have examined their significance in terms of segmental intubation times and position changes required for the completion of colonoscopy. Patients and methods We analyzed 103 consecutive synchronized luminal and magnetic image videos of diagnostic colonoscopies with normal anatomy undertaken by a single experienced operator. Results Deep transverse loops and sigmoid N-loops were more common in females. A deep transverse loop was more likely to be present if a sigmoid alpha-loop or N-loop had formed previously. Patients with sigmoid N-loops were turned more frequently from left lateral to supine before the sigmoid-descending junction was reached, but there was no statistical correlation between completion time and looping pattern. Conclusions This study has reexamined the prevalence of the common looping patterns encountered during colonoscopy and has identified differences between the sexes. This finding may offer an explanation as to why colonoscopy has been shown to be more difficult in females. Although a deep transverse loop following a resolved sigmoid alpha-loop was the most commonly encountered pattern, no statistical correlation between completion time and looping pattern could be shown. It is the first study to examine segmental completion times using a magnetic imager in expert hands.</jats:p

Endoscopy International Open

Background and study aim Magnetic imaging technology is of proven benefit to trainees in colonoscopy, but few studies have examined its benefits in experienced hands. There is evidence that colonoscopy is more difficult in women. We set out to investigate (i) associations between the looping configurations in the proximal and distal colon and (ii) differences in the looping prevalence between the sexes. We have examined their significance in terms of segmental intubation times and position changes required for the completion of colonoscopy. Patients and methods We analyzed 103 consecutive synchronized luminal and magnetic image videos of diagnostic colonoscopies with normal anatomy undertaken by a single experienced operator. Results Deep transverse loops and sigmoid N-loops were more common in females. A deep transverse loop was more likely to be present if a sigmoid alpha-loop or N-loop had formed previously. Patients with sigmoid N-loops were turned more frequently from left lateral to supine before the sigmoid-descending junction was reached, but there was no statistical correlation between completion time and looping pattern. Conclusions This study has reexamined the prevalence of the common looping patterns encountered during colonoscopy and has identified differences between the sexes. This finding may offer an explanation as to why colonoscopy has been shown to be more difficult in females. Although a deep transverse loop following a resolved sigmoid alpha loop was the most commonly encountered pattern, no statistical correlation between completion time and looping pattern could be shown. It is the first study to examine segmental completion times using a magnetic imager in expert hands

Exploration of colonic looping patterns in undisturbed cadaveric specimens.

INTRODUCTION: This study examines sex differences in the disposition of the sigmoid and transverse segments of the colon in undisturbed cadaveric abdomens and relates these findings to the anecdotal observation that colonoscopy is more challenging in females through the formation of tortuous bowel loops. MATERIALS AND METHODS: One hundred and twenty two undisturbed cadaveric abdomens were inspected. Three distinct configuration grades were separately assigned to the sigmoid and transverse segments of the colon on the basis of the pattern of the bowel loops observed in situ. Pearson's chi-squared test was used to analyze sex differences in bowel loop configuration and Spearman's rank correlation coefficient was calculated to identify co-occurrence of configuration grades in the subjects. RESULTS: For the transverse segment, females had higher configuration grades corresponding to longer bowel loops with greater redundancy, compared to males (p = .000047). There was no sex difference in the sigmoid segment grade (p = .21636). Sigmoid and transverse segment grades were highly correlated in the subjects (coefficient = 0.9994). CONCLUSION: Sex differences in the configuration grades of the sigmoid or transverse colonic segments may be a significant contributing factor to increased difficulty of colonoscopy in females