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Developing technologies for the reduction of biofouling and enhancement of membrane functionality and durability are challenging but critical for the advancement of water purification processes. Silver (Ag) is often used in the process of purification due to its anti-fouling properties; however, the leaching of this metal from a filtration membrane significantly reduces its effectiveness. Our study was designed to integrate the positive characteristics of poly vinyl alcohol (PVA) with the controlled incorporation of nano-scale silver ions across the membrane. This approach was designed with three goals in mind: (1) to improve antifouling activity; (2) to prevent leaching of the metal; and (3) to extend the durability of the functionalized membrane. The fabrication method we used was a modified version of manual coating in combination with sufficient pressure to ensure impregnation and proper blending of PVA with cellulose acetate. We then used the spin coater to enhance the cross-linking reaction, which improved membrane durability. Our results indicate that PVA acts as a reducing agent of Ag+ to Ag0 using X-ray photoelectron spectroscopy analysis and demonstrate that the metal retention was increased by more than 90% using PVA in combination with ultraviolet-photo-irradiated Ag+ reduced to Ag0. The Ag+ ions have sp hybrid orbitals, which accept lone pairs of electrons from a hydroxyl oxygen atom, and the covalent binding of silver to the hydroxyl groups of PVA enhanced retention. In fact, membranes with reduced Ag displayed a more effective attachment of Ag and a more efficient eradication of E. coli growth. Compared to pristine membranes, bovine serum albumin (BSA) flux increased by 8% after the initial addition of Ag and by 17% following ultraviolet irradiation and reduction of Ag, whereas BSA rejection increased by 10% and 11%, respectively. The implementation of this hybrid method for modifying commercial membranes could lead to significant savings due to increased metal retention and membrane effectiveness. These enhancements would ultimately increase the membrane’s longevity and reduce the cost/benefit ratio.

Engineering programs suffer a high attrition rate, which causes the nation to graduate much less engineers. A survey of the literature reveals that the high attrition rate is due mainly to the fact that the first year of an engineering program is all fundamental theory and students don't see the INTRODUCTIONesearch shows the continuing decline of bachelor degrees awarded to domestic students in the natural sciences and engineering majors [1]. The lack of student motivation is identified as one contributor to some known problems such as high DWF (D-grade, withdrawal, and failure) rates reported by many institutions [2]. According to [3], undergraduates across the country are choosing to leave science, technology, engineering and math programs (STEM) before they graduate with those degrees, because many of them struggle to complete their degrees in four years, or drop out. A survey of the literature reveals that the major reason of engineering majors' dropout is because the first year of an engineering program is usually filled up with fundamental theory and students don't see the connection to their future career as engineers. This situation may be more profound for minority serving institutions where a larger number of the engineering students are the first in their families to pursue an engineering and/or technology degree. A relatively longer struggle with math, physics and chemistry courses along with the missing linkage of engineering practice result in students' losing interests before they have the opportunity to be enrolled in junior and senior years' program related core curricula. However, researches also indicate that, 93% of engineering degree holders started as an engineering major in their freshmen year, while only 60% graduates from other sciences majors retain their original choice of majors as freshmen [4]. This finding suggests that reducing dropout rates for engineering programs is more important comparing to other majors. Based on these observations, the authors of this article believe that besides attract more youngsters to engineering; another very important strategy is to keep them motivated throughout the freshmen year to cut down the high engineering programs' dropout rate. If both strategies are successfully implemented, the number of engineering graduates will be increased to maintain the U.S. competency and leadership in high-tech industries. Activities related to the first strategy include high school visits, middle school and high school summer camps. The 32© 2011 The Clute Institute second strategy focuses on incoming engineering freshmen. This paper shares an example of achieving the second strategy.

This study investigates poly(vinyl alcohol) (PVA) membranes as controlled release micro-matrices, which can be useful in therapeutic applications for optimizing the administration of drugs. Currently, the use of hydrogels is limited by protein size. This study investigates the delivery of PspA, a large protein of approximately 38 kD. Pneumococcal surface protein A (PspA) has been shown to provide protective immunity against pneumococcal infection and is considered as a pneumococcal vaccine. The protein release experiments demonstrated that from an initial pH 7.4, approximately 60% of PspA diffuse into a neutral environment with an initial burst and a declining rate reaching equilibrium. The results indicate that the protein was successfully incorporated and released from the membrane over time. The hydrogel and protein interaction is temporary, and the membrane system is ideal for protein drug delivery. The data confirm that the protein did not aggregate and was active after release. The protein release is promising and a step forward to develop microneedles to facilitate high molecular weight protein delivery as well as vaccine delivery.

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