Low-density polyethylene membranes, typically filled with triolein, have been previously deployed as passive environmental samplers designed to accumulate nonpolar hydrophobic chemicals from water, sediments, and air. Hydrocarbons in such samplers, known as semipermeable membrane devices (SPMDs), diffuse through pores in the membranes and are trapped in the central hydrocarbon matrix, mimicking...

Motivated by biological protocols that require transfer of large pieces of DNA into cells, we here review several aspects of osmotic swelling and lysis of semipermeable unilamellar vesicles. Swelling involves a continuous phase transition from a fluctuating flaccid state to a maximum volume turgid state, without a divergent correlation length and with exponents that violate the hyperscaling rel...

Desalination that produces clean freshwater from seawater holds the promise of solving the global water shortage for drinking, agriculture and industry. However, conventional desalination technologies such as reverse osmosis and thermal distillation involve large amounts of energy consumption, and the semipermeable membranes widely used in reverse osmosis face the challenge to provide a high th...

premature rupture of membranes (prom) is one of the most common complications of pregnancy that has a major impact on neonatal outcomes. with respect to racial, nutritional and cultural differences between developed and developing countries, this study was conducted to detect the prevalence of neonatal complications following prom and the role of the duration of rupture of membranes in producin...

Sanarelli (1891) is believed to have been the first to employ collodion sacs in animal experimentation. Subsequently, sacs of different types have been used in various in vivo experiments by a number of investigators (see bibliography). Alcohol-ether collodion was employed in each case for the preparation of the semipermeable membranes. In order to withstand the distorting effect of the intesti...

STUDIES COMPARING THE STATE OF HYDRATION AND DEHYDRATION OF RAT LIVER MITOCHONDRIA TO THEIR CONTENT OF ATP, CA, AND FATTY ACID, ALONG WITH THE RATE OF ATP HYDROLYSIS, AS WELL AS MICROSCOPIC APPEARANCE OF MITOCHONDRIA, HAVE LED TO THE FOLLOWING GENERALIZATIONS: 1. The competition between cationic translocations and water translocation for the available chemical energy (ATP) determines under many...

The principle of ultrafiltration (UF) is filtration of solutions or suspensions under pressure through a semipermeable membrane. The membrane has pores that allow the solvent and small molecules to pass through and the larger molecules to be retained. Ultrafiltration may therefore be considered as both a concentration and a fractionation process according to the particular components of interes...

The present dissertation aimed to develop a new microfluidic system for a point-of-care hematocrit device. Stabilization of microfluidic systems via surfactant additives and integration of semipermeable SnakeSkin® membranes was investigated. Both methods stabilized the microfluidic systems by controlling electrolysis bubbles. Surfactant additives, Triton X-100 and SDS stabilized promoted faster...

One of the fundamental problems in membrane biology is that of lipid diversity. The number of chemically different membrane lipids is much larger than other key biological building blocks such as nucleotides, amino acids, and carbohydrates. For instance, a relatively simple biomembrane such as that of the red blood cell contains well over a hundred different lipid species. Except for some metab...

Suspensions of HeLa and S37 cells, with and without added glycerol, were cooled in stages to -79 degrees C. and held at that temperature for 30 minutes. After warming to room temperature the cells were fixed, sectioned, and compared by phase contrast and electron microscopy with similar specimens kept at room temperature. Correlated viability tests were made. Abnormal cytological characteristic...