Advances in highly permeable reverse osmosis (RO) membranes have enabled desalting operations, in which it is practically feasible for the applied pressure to approach the osmotic pressure of the exit brine stream. However, energy cost remains a major contributor to the total cost of water produced by RO membrane desalination. Reduction of the overall cost of water production represents a major challenge and, in the present work, various elements of water production cost are evaluated from the viewpoint of optimization, with respect to various costs (energy, membrane area and permeability, brine management, and pressure drop), as well as the important thermodynamic cross-flow constraint, utilization of energy recovery devices, and operational feed and permeate flow rate constraints. More specifically, in the present study, an approach to the optimization of product water recovery at pressures that approach the osmotic pressure of the exit brine stream is presented via several simple RO process models that utilize highly permeable membranes. The results suggest that it is indeed feasible to refine RO processes to target for operation under the condition of minimum energy consumption, while considering the constraint imposed by the osmotic pressure, as specified by the thermodynamic cross-flow restriction. Although it is shown that multistage RO provides energy savings, this is at the expense of greater membrane area cost. Overall, as process costs above energy costs are added, the operational point for achieving minimum water production cost shifts to higher recoveries. Although the newer generation of RO membranes can allow high recovery operations at lower pressures, limitations due to mineral scaling and fouling impose additional constraints. The incorporation of these phenomena in the optimization approach is the subject of ongoing research.

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With the increasing prevalence of obesity in women of reproductive age there is a need to understand the ramifications of this on offspring. The purpose of this study is to investigate the programming effects of maternal obesity during preconception and the preconception/gestational period on adiposity and adipose tissue inflammation in offspring using an animal model. Adult female C57Bl/6J mice were assigned either normal diet, high fat diet (HFD) prior to pregnancy, or HFD prior to and through pregnancy. Some offspring were maintained on normal diet while others started HFD later in life. Offspring were assessed for body composition and metabolic responses. Lipid storing tissues were evaluated for expansion and inflammation. Male offspring from the preconception group had the greatest weight gain, most subcutaneous adipose tissue, and largest liver mass when introduced to postnatal HFD. Male offspring of the preconception/gestation group had worsened glucose tolerance and an increase in resident (CD11c−) adipose tissue macrophages (ATMs) when exposed to postnatal HFD. Female offspring had no significant difference in any parameter between the diet treatment groups. In conclusion, this study demonstrates that prenatal and pregnancy windows have independent programming effects on offspring. Preconception exposure affects body composition and adiposity while gestation exposure affects metabolism and tissue immune cell phenotypes.

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We study the energy consumption optimization of a reverse osmosis water desalination process producing a constant permeate flow in the presence of feed concentration fluctuation. We propose a time-varying optimal operation strategy that can significantly reduce the specific energy consumption compared to time-invariant process operation. We present both computational and experimental results that demonstrate the effectiveness of the proposed optimal operation policy.

The carboxylation of glutamic acid residues to ␥-carboxyglutamic acid (Gla) by the vitamin K-dependent ␥-glutamyl carboxylase (␥-carboxylase) is an essential posttranslational modification required for the biological activity of a number of proteins, including proteins involved in blood coagulation and its regulation. Heterozygous mice carrying a null mutation at the ␥-carboxylase (

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