Poly(viny1 alcohol) (PVA) hydrogels were prepared by treating 15 or 20% aqueous PVA solutions to repeated cycles of freezing for 6 or 12 h at 20°C and thawing for 2 h at 25°C. The resulting gels did not contain any leachable toxic crosslinking agents or other residues. Their adhesive characteristics were examined using tensile experiments in contact with bovine submaxillary mucin. As the number...

Controlled delivery of hydrophilic proteins is an important therapeutic strategy. However, widely used methods for protein delivery suffer from low incorporation efficiency and loss of bioactivity. The versatile interfacial polyelectrolyte complexation (IPC) fibers have the capacity for precise spatiotemporal release and protection of protein, growth factor, and cell bioactivity. Yet its weak m...

Pentoxifylline (PF) is used to enhance motility of spermatozoa from infertile human subjects. We have previously shown that 0.45 mM PF improved capacitation of spermatozoa and fertilization of oocytes in vitro in hamsters. The present study was carried out to assess PF-induced changes in motility kinematics of hamster spermatozoa by a computer-aided sperm analyser (CASA) and determine the timin...

An environmentally friendly and inexpensive substitute to the widely used poly(vinyl alcohol) (PVA) has been developed from soy proteins for textile warp sizing. Textile processing is the major source of industrial water pollution across the world, and sizing and desizing operations account for nearly 30 % of the water consumed in a textile plant. PVA is one of the most common sizing agents use...

Partial chemical modification of poly(vinyl alcohol) (PVA) was performed through tosylation followed by azidation. Amine functional PVA was also prepared by grafting propargylamine using click chemistry reaction. Through this approach, a tosyl group (a good leaving group), azide group (a group used in click chemistry) and amine group (a group used for amidation) were attached to PVA polymer cha...

Alpha-amylase was immobilized onto polyaniline-polyvinyl alcohol (PAni-PVA) film by cross linking with glutaraldehyde. The activity yield and immobilization efficiency was calculated as 13.58% and 30.60% respectively. The PAni-PVA-Amylase films were characterized by Fourier Transform Infrared Spectroscopy (FTIR) and amylase activity assay. The immobilized α-amylase had its optimum activity at p...

Polyvinyl alcohol (PVA) containing the fixative mercuric chloride is considered the "gold standard" for the fixation of ova and parasites in the preparation of permanently stained smears of stool specimens. However, mercuric chloride is potentially hazardous to laboratory personnel and presents disposal problems. We compared three new alternative, nontoxic fixatives with PVA, analyzing ease of ...

We studied whether the oxygen cost of mechanical energy is time-invariant in the excised, cross-circulated canine heart. The total mechanical energy generated by ventricular contraction can be quantified by the total pressure-volume area (PVA) according to the time-varying eiastance model. In this model, mechanical energy generated until a specified time (t) during systole can be quantified by ...

Polyvinyl alcohol (PVA) hydrogels are materials for potential use in burn healing. Silver nanoparticles can be synthesized within PVA hydrogels giving antimicrobial hydrogels. Hydrogels have to be swollen prior to their application, and the common medium available for that in hospitals is saline solution, but the hydrogel could also take up some of the wound's fluid. This work developed gamma-i...

We introduce a novel computational framework, Principal Variety Analysis (PVA), for primarily nonlinear data modeling. PVA accommodates algebraic sets as the target subspace through which limitations of other existing approaches is dealt with. PVA power is demonstrated in this paper for learning kinematics of objects, as an important application. PVA takes recorded coordinates of some pre-speci...