No / Intermittent pneumatic compression (IPC) is a mechanical method of delivering compression to swollen limbs that can be used to treat venous leg ulcers and limb swelling due to lymphoedema. This review analyses the evidence for the effectiveness of IPC as a treatment for venous leg ulcers. OBJECTIVES: To determine whether IPC increases the healing of venous leg ulcers. To determine the effects of IPC on health related quality of life of venous leg ulcer patients. SEARCH STRATEGY: We searched the Cochrane Wounds Group Specialised Register (December 2007); the Cochrane Central Register of Controlled Trials (CENTRAL) - The Cochrane Library Issue 4, 2007; Ovid MEDLINE - 2006 to November Week 2 2007; Ovid EMBASE - 2006 to 2007 Week 49 and Ovid CINAHL - 2006 to December Week 1 2007. SELECTION CRITERIA: Randomised controlled studies either comparing IPC with control (sham IPC or no IPC) or comparisons between IPC treatment regimens, in venous ulcer management were included. DATA COLLECTION AND ANALYSIS: Data extraction and assessment of study quality were undertaken by one author and checked by a second. MAIN RESULTS: Seven randomised controlled trials (including 367 people in total) were identified. Only one trial reported both allocation concealment and blinded outcome assessment. In one trial (80 people) more ulcers healed with IPC than with dressings (62% vs 28%; p=0.002). Four trials compared IPC with compression against compression alone. The first of these trials (45 people) found increased ulcer healing with IPC plus compression than with compression alone (relative risk for healing 11.4, 95% Confidence Interval 1.6 to 82). The remaining three trials (122 people) found no evidence of a benefit for IPC plus compression compared with compression alone. One small trial (16 people) found no difference between IPC (without additional compression) and compression bandages alone. One trial compared different ways of delivering IPC (104 people) and found that rapid IPC healed more ulcers than slow IPC (86% vs 61%; log rank p=0.003). AUTHORS' CONCLUSIONS: IPC may increase healing compared with no compression, but it is not clear whether it increases healing when added to treatment with bandages, or if it can be used instead of compression bandages. Rapid IPC was better than slow IPC in one trial. Further trials are required to determine whether IPC increases the healing of venous leg ulcers when used in modern practice where compression therapy is widely used.

Center-notched and unnotched specimens cut from Celion 3000/PMR15 woven composite panels with 60% fiber volume fraction were tested under quasi-static compressive load to failure at room temperature. Micrographic evidence clearly identifies the mode of compressive failure as fiber kinking. Each fiber in the kink fractures because of a combination of compressive and shear stresses. A post failure mechanism follows the local fiber bundle failures, which completely deforms the material by large cracks. ln center notched specimens, fiber kinks start from the notch and propagate to some distance from the notch before the post failure takes place. The effect of bundle interactions on stresses and strains was clearly distinguished by comparing the results of the finite element analysis of a bundle surrounded by other plies to the results of the Moire interferometry on the edge of a laminate. A model was introduced which incorporated the micromechanical geometry as well as the constituent properties to predict the notched and unnotched compressive strengths of the woven material. For notched strength predictions, the Average Stress Criterion was used, and the characteristic distance was found to be a function of laminate thickness. Predicted notched and unnotched strengths correlate very well with the experimental results. / Ph. D.

Advances in electronics, computer and information technology are fueling major changes in the area of power systems instrumentations. More and more microprocessor based digital instruments are replacing older type of meters. Extensive deployment of digital instruments are generating vast quantities of data which is creating information pressure in Utilities. The legacy SCADA based data management systems do not support management of such huge data. As a result utilities either have to delete or store the metered information in some compact discs, tape drives which are unreliable. Also, at the same time the traditional integrated power industry is going through a deregulation process. The market principle is forcing competition between power utilities, which in turn demands a higher focus on profit and competitive edge. To optimize system operation and planning utilities need better decision making processes which depend on the availability of reliable system information. For utilities it is becoming clear that information is a vital asset. So, the utilities are now keen to store and use as much information as they can. Existing SCADA based systems do not allow to store data of more than a few months. So, in this dissertation effectiveness of compression algorithms in compressing real time operational data has been assessed. Both, lossy and lossless compression schemes are considered. In lossless method two schemes are proposed among which Scheme 1 is based on arithmetic coding and Scheme 2 is based on run length coding. Both the scheme have 2 stages. First stage is common for both the schemes. In this stage the consecutive data elements are decorrelated by using linear predictors. The output from linear predictor, named as residual sequence, is coded by arithmetic coding in Scheme 1 and by run length coding in Scheme 2. Three different types of arithmetic codings are considered in this study : static, decrement and adaptive arithmetic coding. Among them static and decrement codings are two pass methods where the first pass is used to collect symbol statistics while the second is used to code the symbols. The adaptive coding method uses only one pass. In the arithmetic coding based schemes the average compression ratio achieved for voltage data is around 30, for frequency data is around 9, for VAr generation data is around 14, for MW generation data is around 11 and for line flow data is around 14. In scheme 2 Golomb-Rice coding is used for compressing run lengths. In Scheme 2 the average compression ratio achieved for voltage data is around 25, for frequency data is around 7, for VAr generation data is around 10, for MW generation data is around 8 and for line flow data is around 9. The arithmetic coding based method mainly looks at achieving high compression ratio. On the other hand, Golomb-Rice coding based method does not achieve good compression ratio as arithmetic coding but it is computationally very simple in comparison with the arithmetic coding. In lossy method principal component analysis (PCA) based compression method is used. From the data set, a few uncorrelated variables are derived and stored. The range of compression ratio in PCA based compression scheme is around 105-115 for voltage data, around 55-58 for VAr generation data, around 21-23 for MW generation data and around 27-29 for line flow data. This shows that the voltage parameter is amenable for better compression than other parameters. Data of five system parameters - voltage, line flow, frequency, MW generation and MVAr generation - of Souther regional grid of India have been considered for study. One of the aims of this thesis is to argue that collected power system data can be put to other uses as well. In particular we show that, even mining the small amount of practical data (collected from SRLDC) reveals some interesting system behavior patterns. A noteworthy feature of the thesis is that all the studies have been carried out considering data of practical systems. It is believed that the thesis opens up new questions for further investigations.

No description available.

No description available.

No description available.

Signal compression is necessary part for ECG scanning, because of relatively big amount of data, which must be transmitted primarily wirelessly for analysis. Because of the wireless sending it is necessary to minimize the amount of data as much as possible. To minimize the amount of data, lossless or lossy compression algorithms are used. This work describes an algorithm SPITH and newly created experimental method, based on PNG, and their testing. This master’s thesis there is also a bank of ECG signals with parallel sensed accelerometer data. In the last part, modification of SPIHT algorithm, which uses accelerometer data, is described and realized.

No description available.

Indiana University-Purdue University Indianapolis (IUPUI) / Exodontia, or extraction of teeth, has been a well-documented dental treatment that forms one of the foundations of dentistry. The steps associated with extracting teeth have changed little in the last century and these steps are largely part of the dogma of dentistry. One such step is that of socket compression post-extraction. Rationale for socket compression after extraction is manifold. They include: shorter healing times, fewer dry sockets and re-approximating walls that were stretched in the elevation and delivery stages of extractions. The purpose of this study was to determine if post-extraction ridge compression negatively affected alveolar ridge dimensions when compared to sites that are not compressed post-extraction. Secondary outcome measures will identify if socket compression/re-approximation affects the rate of soft tissue closure or occurrence of alveolar osteitis. In this study, 14 subjects were recruited. Eight subjects formed the compression group, while six formed the non-compression group. The subjects in the compression group received compression of their alveolar ridges after extraction to approximate their original pre-extraction width. The subjects in the non-compression group did not receive ridge compression. Each subject had pre-extraction and post-extraction CBCT scans along with post-operative follow up visits at 1, 2, and 4 weeks post-extraction. The present investigation found that with respect to changes in ridge width, sites that were compressed did not lose significantly more dimension than those that were not. With respect to ridge height, sites that were compressed did not lose significantly more dimension than those that were not. Sites that were compressed and sites that were not, healed at approximately the same rate, with respect to soft tissue closure. While the results showed a lack of statistical significance between both groups, there appears to be a trend towards the ridge compression group having a smaller ridge width. Such a trend was not noted with soft tissue closure, thereby invalidating the rationale for socket compression after extraction. One of the limitations of this pilot study is the small sample size. Further validation of these results must be done with a larger sample size in order to provide clinical guidance to dental practitioners.

No description available.