Axisymmetric Drop Shape Analysis (ADSA): An Outline.

Drop shape techniques for the measurement of interfacial tension are powerful, versatile and flexible. The shape of the drop/bubble depends on the balance between surface tension and external forces, e.g.

Venous glucose, serum lactate and base deficit as biochemical predictors of mortality in patients with polytrauma.

Background: The trauma and injury severity score (TRISS) and Acute Physiology and Chronic Health Evaluation IV (APACHE IV) are accurate but complex. This study aimed to compare venous glucose, levels of serum lactate, and base deficit in polytraumatized patients as simple parameters to predict the mortality in these patients versus (TRISS) and (APACHE IV).

Methods: This was a comparative cross-sectional study of 282 patients with polytrauma presented to the Emergency Department (ED).

Laplacian drop shapes and effect of random perturbations on accuracy of surface tension measurement for different drop constellations.

Theoretical drop shapes are calculated for three drop constellations: pendant drops, constrained sessile drops, and unconstrained sessile drops. Based on total Gaussian curvature, shape parameter and critical shape parameter are discussed as a function of different drop sizes and surface tensions. The shape parameter is linked to physical parameters for every drop constellation.

Total Gaussian curvature, drop shapes and the range of applicability of drop shape techniques.

Drop shape techniques are used extensively for surface tension measurement. It is well-documented that, as the drop/bubble shape becomes close to spherical, the performance of all drop shape techniques deteriorates. There have been efforts quantifying the range of applicability of drop techniques by studying the deviation of Laplacian drops from the spherical shape.

Accuracy of surface tension measurement from drop shapes: the role of image analysis.

Axisymmetric Drop Shape Analysis (ADSA) has been extensively used for surface tension measurement. In essence, ADSA works by matching a theoretical profile of the drop to the extracted experimental profile, taking surface tension as an adjustable parameter. Of the three main building blocks of ADSA, i.

Effect of surfactant concentration, compression ratio and compression rate on the surface activity and dynamic properties of a lung surfactant.

This paper reports dynamic surface tension experiments of a lung surfactant preparation, BLES, for a wide range of concentrations, compression ratios and compression rates. These experiments were performed using Axisymmetric Drop Shape Analysis-Constrained Sessile Drop (ADSA-CSD). The main purpose of the paper is to interpret the results in terms of physical parameters using the recently developed Compression-Relaxation Model (CRM).

Range of validity of drop shape techniques for surface tension measurement.

Drop shape techniques are widely used for surface tension measurement. As the shape becomes close to spherical, the performance of drop shape techniques deteriorates. A quantitative criterion called shape parameter was previously introduced to quantify the meaning of "well-deformed" drops and "close to spherical" drops.

A double injection ADSA-CSD methodology for lung surfactant inhibition and reversal studies.

This paper presents a continuation of the development of a drop shape method for film studies, ADSA-CSD (Axisymmetric Drop Shape Analysis-Constrained Sessile Drop). ADSA-CSD has certain advantages over conventional methods. The development presented here allows complete exchange of the subphase of a spread or adsorbed film.

Mixed DPPC/DPPG monolayers at very high film compression.

A drop shape technique using a constrained sessile drop constellation (ADSA-CSD) has been introduced as a superior technique for studying spread films specially at high collapse pressures [Saad et al. Langmuir 2008, 24, 10843-10850]. It has been shown that ADSA-CSD has certain advantages including the need only for small quantities of liquid and insoluble surfactants, the ability to measure very low surface tension values, easier deposition procedure, and leak-proof design.

Axisymmetric drop shape analysis for estimating the surface tension of cell aggregates by centrifugation.

Biological tissues behave in certain respects like liquids. Consequently, the surface tension concept can be used to explain aspects of the in vitro and in vivo behavior of multicellular aggregates. Unfortunately, conventional methods of surface tension measurement cannot be readily applied to small cell aggregates.

Axisymmetric drop shape analysis-constrained sessile drop (ADSA-CSD): a film balance technique for high collapse pressures.

Collapse pressure of insoluble monolayers is a property determined from surface pressure/area isotherms. Such isotherms are commonly measured by a Langmuir film balance or a drop shape technique using a pendant drop constellation (ADSA-PD). Here, a different embodiment of a drop shape analysis, called axisymmetric drop shape analysis-constrained sessile drop (ADSA-CSD) is used as a film balance.

Upper extremity arteriovenous fistula does not affect pulse oximetry readings.

Aim: Arteriovenous fistula (AVF) is usually surgically created in a patient's upper extremity to provide adequate blood flow during haemodialysis. Blood flow distal to an AVF is altered and theoretically could change pulse oximetry (SpO2) reading, systemic blood pressure and skin temperature. The authors conducted a prospective case-control study to measure changes in these parameters in the upper extremity of patients who have had an AVF.