Breakthrough Studies Research Articles

Erwinia amylovora in the genomics era : from genomes to pathogen virulence, regulation, and disease control strategies

The publication of the first Erwinia amylovora genome has greatly accelerated and advanced our understanding of the fire blight organism. With the availability of multiple genomes, it quickly became clear that chromosomal diversity is relatively small, and that most of the pan-genome variance is attributable to plasmids. In addition to gaining a more detailed view of the known virulence factors, genomics has enabled new breakthrough studies of virulence regulation mechanisms. Furthermore, several niche adaptation and ecological fitness factors, though not directly influencing virulence, have been studied in greater detail, providing novel insights into the physiology and ecology of the bacterium. Additionally, application of genome data has yielded improved diagnostics and enabled population studies at different geographic scales.

Adsorption of Ni(II) on alkali treated pineapple residue (Ananas comosus L.): Batch and column studies

The novel alkali-treated pineapple residue was utilized for sequestration of Ni(II) ions from aqueous solution. On treatment with Sodium hydroxide the metal binding sites (free O−) of pineapple residue enhanced. Lignin and hemi-cellulose being substantial components in pineapple played a vital role in nickel adsorption. The prime functional groups present in ATPR that participated in nickel adsorption were hydroxyl and carbonyl groups, affirmed by the FTIR analysis. In a batch system maximum adsorption capacity (4.51 mgg−1) was obtained at solution pH 4–6, in 60min at 30°C. The increase in adsorption capacity from 0.95 to 7.72mgg−1 with increase in concentration from 10 to 100mgL−1 confirmed the dependence of adsorption on metal ion concentration. The equilibrium data was analyzed by Langmuir, Freundlich and temkin isotherm models and was found to be best followed by Langmuir and Freundlich isotherm models at 50⁰C. The maximum adsorption capacity (qmax) from Langmuir isotherm model was found to be 17.56mgg−1. Kinetic data analysis revealed that pseudo-second order kinetic model was best obeyed, implying that chemisorption was the rate determining step. Thermodynamic parameters (∆G°, ∆H⁰, ∆S⁰) exhibited feasible, endothermic and spontaneous nature of adsorption. The breakthrough and desorption studies were conducted by column operation and corresponding breakthrough and exhaustive capacities were found to be 20 and 50mgg−1 respectively.

Two-Dimensional Materials as Prospective Scaffolds for Mixed-Matrix Membrane-Based CO2 Separation.

Membrane-based CO2 separation technology plays a significant role in environmental remediation and clean energy. Two-dimensional (2D) materials with atomically precise structures have emerged as prospective scaffolds to develop mixed-matrix membranes (MMMs) for gas separation. Summarized in this perspective review are the latest breakthrough studies in the synthesis of 2D-material-based MMMs to separate CO2 from gas mixtures. 2D materials including graphene oxide (GO), metal-organic framework (MOF)-derived nanosheets, covalent organic frameworks (COFs), and transition metal dichalcogenides (TMDs), as fascinating building blocks, have been comprehensively summarized, together with a focus on synthetic processes and gas separation properties. Challenges and the latest advances in the manufacture of novel synthetic 2D materials are briefly discussed to foresee emerging opportunities for the development of new generations of 2D-material-based MMMs.

The Potential of Palm Oil Waste Biomass in Indonesia in 2020 and 2030

During replanting activity in oil palm plantation, biomass including palm frond and trunk are produced. In palm oil mills, during the conversion process of fresh fruit bunches (FFB) into crude palm oil (CPO), several kinds of waste including empty fruit bunch (EFB), mesocarp fiber (MF), palm kernel shell (PKS), palm kernel meal (PKM), and palm oil mills effluent (POME) are produced. The production of these wastes is abundant as oil palm plantation area, FFB production, and palm oil mills spread all over 22 provinces in Indonesia. These wastes are still economical as they can be utilized as sources of alternative fuel, fertilizer, chemical compounds, and biomaterials. Therefore, breakthrough studies need to be done in order to improve the added value of oil palm, minimize the waste, and make oil palm industry more sustainable.

Functionalized single-walled carbon nanotubes: cellular uptake, biodistribution and applications in drug delivery

The unique properties of single-walled carbon nanotubes (SWNTs) enable them to play important roles in many fields. One of their functional roles is to transport cargo into cell. SWNTs are able to traverse amphipathic cell membranes due to their large surface area, flexible interactions with cargo, customizable dimensions, and surface chemistry. The cargoes delivered by SWNTs include peptides, proteins, nucleic acids, as well as drug molecules for therapeutic purpose. The drug delivery functions of SWNTs have been explored over the past decade. Many breakthrough studies have shown the high specificity and potency of functionalized SWNT-based drug delivery systems for the treatment of cancers and other diseases. In this review, we discuss different aspects of drug delivery by functionalized SWNT carriers, diving into the cellular uptake mechanisms, biodistribution of the delivery system, and safety concerns on degradation of the carriers. We emphasize the delivery of several common drugs to highlight the recent achievements of SWNT-based drug delivery.

Cellular and Molecular Characterization of Microglia: A Unique Immune Cell Population.

Microglia are essential for the development and function of the adult brain. Microglia arise from erythro-myeloid precursors in the yolk sac and populate the brain rudiment early during development. Unlike monocytes that are constantly renewed from bone marrow hematopoietic stem cells throughout life, resident microglia in the healthy brain persist during adulthood via constant self-renewal. Their ontogeny, together with the absence of turnover from the periphery and the singular environment of the central nervous system, make microglia a unique cell population. Supporting this notion, recent genome-wide transcriptional studies revealed specific gene expression profiles clearly distinct from other brain and peripheral immune cells. Here, we highlight the breakthrough studies that, over the last decades, helped elucidate microglial cell identity, ontogeny, and function. We describe the main techniques that have been used for this task and outline the crucial milestones that have been achieved to reach our actual knowledge of microglia. Furthermore, we give an overview of the “microgliome” that is currently emerging thanks to the constant progress in the modern profiling techniques.

Novel players in X inactivation: insights into Xist-mediated gene silencing and chromosome conformation.

The nuclear long noncoding RNA (lncRNA) Xist ensures X-chromosome inactivation (XCI) in female placental mammals. Although Xist is one of the most intensively studied lncRNAs, the mechanisms associated with its capacity to trigger chromosome-wide gene silencing, the formation of facultative heterochromatin and an unusual 3D conformation of the inactive X chromosome (Xi) have remained elusive. Now researchers have identified novel functional partners of Xist in a series of breakthrough studies, using unbiased techniques to isolate Xist-bound proteins, as well as forward genetic screens. In addition, important insights into the 3D organization of Xi and its relation to gene expression have been obtained. In this Review, we discuss how this new information is providing a recipe for deciphering XCI mechanisms by which a multitasking RNA can structurally and functionally transform an active chromosome into uniquely organized facultative heterochromatin.

Next generation of network medicine: interdisciplinary signaling approaches.

In the last decade, network approaches have transformed our understanding of biological systems. Network analyses and visualizations have allowed us to identify essential molecules and modules in biological systems, and improved our understanding of how changes in cellular processes can lead to complex diseases, such as cancer, infectious and neurodegenerative diseases. "Network medicine" involves unbiased large-scale network-based analyses of diverse data describing interactions between genes, diseases, phenotypes, drug targets, drug transport, drug side-effects, disease trajectories and more. In terms of drug discovery, network medicine exploits our understanding of the network connectivity and signaling system dynamics to help identify optimal, often novel, drug targets. Contrary to initial expectations, however, network approaches have not yet delivered a revolution in molecular medicine. In this review, we propose that a key reason for the limited impact, so far, of network medicine is a lack of quantitative multi-disciplinary studies involving scientists from different backgrounds. To support this argument, we present existing approaches from structural biology, 'omics' technologies (e.g., genomics, proteomics, lipidomics) and computational modeling that point towards how multi-disciplinary efforts allow for important new insights. We also highlight some breakthrough studies as examples of the potential of these approaches, and suggest ways to make greater use of the power of interdisciplinarity. This review reflects discussions held at an interdisciplinary signaling workshop which facilitated knowledge exchange from experts from several different fields, including in silico modelers, computational biologists, biochemists, geneticists, molecular and cell biologists as well as cancer biologists and pharmacologists.

A low pressure cryogenic trap for cleaning of feed stream in dilution refrigerator

Cryogenic traps are frequently used for removing impurities from gases and conventionally use the cryo-adsorption technique with activated carbon adsorbents. Such purification instruments are often operating at high pressure to aid the adsorption process to its maximum extent. In a system which operates at low pressure and low gas flow rates the residual concentration of the adsorptive gas is determined only by its vapor pressure in relation to the total pressure. In a dilution refrigerator the process gas circulates at sub-atmospheric pressure and it becomes a challenge to remove impurities by cryogenic trap at substantially low pressures. In this paper we describe a simple one column liquid nitrogen cooled cryogenic trap for entrapment of O2 and N2 from the circulating process gas. Two different types of adsorbents, LiLSX and activated carbon were investigated using volumetric adsorption approach and break-through studies.

Breakthrough Studies of Methyl Salicylate and DMMP Mixed in Methyl Salicylate with Pressure Swing Adsorption Composed of 13X Molecular Sieves

A test procedure for pressure swing adsorption (PSA) was established and elucidated for the air purification using methyl salicylate (MeS) and 5% (v/v) dimethyl methyl phosphonate (DMMP) in MeS containing air stream as feed. The effect of feed flow rate was studied by varying the flow from 5 lpm to 20 lpm, for both the molecules at 25 oC and 4 kg/cm2. The results revealed that the flow rate had a significant influence on the breakthrough time. A method was developed for the determination of feed, purge, and dry air composition, by the solvent extraction method using the XAD-2 and the average concentrations reported. The 13X molecular sieves were characterised for its structural and textural properties such as BET- SA, XRD, and FT-IR. The temperature programmed desorption of DMMP and MeS on 13X clearly demonstrated that it was easily regenerated at ~320 °C after prolonged field operation of PSA. The PSA results obtained with PSA composed molecular sieves appeared to give promising technology for air purification and specifically to the chemical warfare agents simulants.

Antiviral Activity of Bictegravir (GS-9883), a Novel Potent HIV-1 Integrase Strand Transfer Inhibitor with an Improved Resistance Profile.

Bictegravir (BIC; GS-9883), a novel, potent, once-daily, unboosted inhibitor of HIV-1 integrase (IN), specifically targets IN strand transfer activity (50% inhibitory concentration [IC50] of 7.5 ± 0.3 nM) and HIV-1 integration in cells. BIC exhibits potent and selective in vitro antiretroviral activity in both T-cell lines and primary human T lymphocytes, with 50% effective concentrations ranging from 1.5 to 2.4 nM and selectivity indices up to 8,700 relative to cytotoxicity. BIC exhibits synergistic in vitro antiviral effects in pairwise combinations with tenofovir alafenamide, emtricitabine, or darunavir and maintains potent antiviral activity against HIV-1 variants resistant to other classes of antiretrovirals. BIC displayed an in vitro resistance profile that was markedly improved compared to the integrase strand transfer inhibitors (INSTIs) raltegravir (RAL) and elvitegravir (EVG), and comparable to that of dolutegravir (DTG), against nine INSTI-resistant site-directed HIV-1 mutants. BIC displayed statistically improved antiviral activity relative to EVG, RAL, and DTG against a panel of 47 patient-derived HIV-1 isolates with high-level INSTI resistance; 13 of 47 tested isolates exhibited >2-fold lower resistance to BIC than DTG. In dose-escalation experiments conducted in vitro, BIC and DTG exhibited higher barriers to resistance than EVG, selecting for HIV-1 variants with reduced phenotypic susceptibility at days 71, 87, and 20, respectively. A recombinant virus with the BIC-selected M50I/R263K dual mutations in IN exhibited only 2.8-fold reduced susceptibility to BIC compared to wild-type virus. All BIC-selected variants exhibited low to intermediate levels of cross-resistance to RAL, DTG, and EVG (<8-fold) but remained susceptible to other classes of antiretrovirals. A high barrier to in vitro resistance emergence for both BIC and DTG was also observed in viral breakthrough studies in the presence of constant clinically relevant drug concentrations. The overall virologic profile of BIC supports its ongoing clinical investigation in combination with other antiretroviral agents for both treatment-naive and -experienced HIV-infected patients.

Adsorption characteristics of chemically modified Caryota urens seeds for the removal of Cu(II) from aqueous solution: Isotherms and kinetic studies

In the present work Caryota urens seeds (CUS), a plant based adsorbent, were modified chemically using different chemical reagents. Among all reagents, NaOH was found to be the most effective modificant. Alkali treated C. urens seeds (ATCUS) exhibited higher removal efficiency (99%) towards Cu(II) than the raw CUS (91%). Characterization of both raw and modified CUS was carried out via SEM, EDX and FTIR analysis. Various physico-chemical parameters such as effect of contact time, initial Cu(II) concentration, pH, adsorbent dose and temperature were investigated using batch process to optimize conditions for maximum adsorption. Adsorption process was found to be fast with equilibrium time of 30–60min was investigated over concentration range of 10–100mgL−1. Optimum pH was found to be 6. Maximum adsorption capacity (qm) as calculated from Langmuir isotherm was found to be 27.39mgg−1. Thermodynamic parameters, ∆H° and ∆G°, indicated that the process was endothermic and spontaneous in nature. Analysis of adsorption kinetics indicated better applicability of pseudo-second order kinetic model. Breakthrough and desorption studies were carried out by column process. Breakthrough and exhaustive capacities were found to be 6 and 15mgg−1, respectively. Regeneration study of ATCUS indicated that the adsorbent can be used effectively upto three consecutive cycles.

Dynamic Column Breakthrough and Process Studies of High-Purity Oxygen Production Using Silver-Exchanged Titanosilicates

Many medical and industrial applications require high-purity oxygen. Because of the similar physical properties of oxygen and argon, this separation is very challenging, and very few commercial adsorbents offer the ability to separate the two gases. Silver-exchanged titanosilicates (Ag-ETS-10) have the potential to separate these gases based on their adsorption affinities. In this work, adsorption isotherms of O2, Ar, and N2 on Ag-ETS-10 extrudates have been measured using a volumetric technique and described using a Langmuir isotherm. Single, binary, and ternary breakthrough profiles were measured using a laboratory-scale dynamic column breakthrough apparatus. These profiles have been modeled by writing mass and energy balances that are solved using the finite volume technique. The model was able to predict the experimental profiles to a high degree of accuracy. A simple vacuum swing adsorption process was simulated using mathematical models to demonstrate the potential of the material to produce high-pu...

Mixed matrix nanofiber as a flow-through membrane adsorber for continuous Li+ recovery from seawater

A polysulfone (PSf)-based mixed matrix nanofiber (MMN) dispersed with particulate lithium ion sieves (LIS) was developed as a flow-through membrane Li+ adsorber. The MMN was prepared via electrospinning, thermal annealing, and acid pickling (i.e. activated LIS: Li0.67H0.96Mn1.58O4 or MO). The unique dimensional property of the macroporous MMN promoted high MO exposure and distribution on the nanofiber surface. Minimal losses in Li+ adsorption capacity and kinetics, elicited by the PSf matrix, were observed. Moreover, the PSf matrix effectively improved the Li+ selectivity of MO as it alleviated the sorption of interfering cations. As membranes, the MMNs were highly permeable to water under minimal trans-membrane pressure. The convective flow of seawater through the highly accessible MMN facilitated the fast Li+ transport to the MO surface. Breakthrough studies revealed that a balance between kinetics and dynamic Li+ adsorption capacity could be obtained at optimal seawater/MMN contact time, which was easily achieved by adjusting the feed flow-rate or MMN thickness. Continuous flow-through operations were successfully controlled at a very short adsorption–desorption cycle time (one day) while maintaining the dynamic Li+ adsorption capacity of the MMN. Cycled operations confirmed the regenerability of the MMN and its adsorption performance consistency. Enrichment of Li+ was successfully done by repeated Li+ desorption in a small volume of acid solution. Overall results demonstrated the strong potential of the flow-through MMN membrane adsorber for continuous Li+ recovery from alternative resources like seawater.

A novel polar-modified post-cross-linked resin and its enhanced adsorption to salicylic acid: Equilibrium, kinetics and breakthrough studies

Improving the surface polarity is of significance for the post-cross-linked resins to enhance their adsorption to polar aromatic compounds. In the present study, we prepared a novel polar-modified post-cross-linked PDEpc_D by the Friedel–Crafts alkylation reaction and the amination reaction, the Brunauer–Emmett–Teller (BET) surface area and pore volume increased significantly after the Friedel–Crafts alkylation reaction and the surface polarity improved greatly after the amination reaction. Batch adsorption showed that PDEpc_D possessed a much enhanced adsorption to salicylic acid as compared the precursors PDE and PDEpc as well as the non-polar post-cross-linked PDVBpc. The equilibrium data was characterized by the Freundlich model, π–π stacking, hydrogen bonding and static interaction were the possible driving forces. The adsorption was a fast process and the kinetic data obeyed the micropore diffusion model. Column adsorption–desorption experiments suggested that PDEpc_D was a potential candidate for adsorptive removal of salicylic acid from aqueous solution.

Neurosurgical Research – Cutting Edge: Recent Advancements and Shortcomings in Neural Growth and Regeneration

Advancements in neurosurgical research have been central to understanding the underlying process of neural growth and regeneration (neurogenesis) and its application in the treatment and management of neurological pathologies. Recent work has shown the adult brain and central nervous system (CNS) to contain neuronal progenitors, precursor molecules as well as stem cells which play key roles in the new generation of neurones, astrocytes and oligodendrocytes. Whilst also challenging the previous dogma that no new neurones are born into the adult mammalian CNS and brain; this paper draws upon and presents an up-to-date picture of currently used “in vitro” and “in vivo” models for the study of novel techniques concerning the integration of neurones into existing neural circuitry. Breakthrough studies in Axonal Regeneration; The Application of Growth Factors; Stem cell grafting and proliferation; Synthetic materials technology; are just a few examples of key areas which have gained extensive interest, to ensure the successful clinical application of neurogenesis in various neurological pathologies. Challenges in the field are also addressed, where a future outlook to improve these novel techniques and potential areas of expandable research is also indicated.

Protein adsorption to poly(ethylenimine)-modified Sepharose FF: VI. Partial charge neutralization drastically increases uptake rate

The adsorption and elution behaviors of bovine serum albumin (BSA) on poly(ethylenimine) (PEI)-grafted Sepharose FF resins were recently studied and a critical ionic capacity (cIC; 600mmol/L) was found, above which the uptake rate increased drastically due to the occurrence of significant “chain delivery” effect. Moreover, above the cIC value, higher salt concentrations were required for protein elution due to the high charge density of the resins. In this work, we have reduced the charge density on the PEI chains of a PEI-grafted resin by neutralization of the amine groups with sodium acetate. PEI-modified resin with IC of 740mmol/L (FF-PEI-L740, IC>cIC) was chosen as the starting material, and three resins with residual IC values of 660, 560 and 440mmol/L (FF-PEI-R440) were obtained. The adsorption and chromatographic behaviors of these resins for BSA were investigated. It was found that, with IC decreasing from 740 to 440mmol/L, the adsorption capacity kept almost unchanged; the effective protein diffusivity (De) also showed negligible variations as IC decreased from 740 to 560mmol/L (De/D0=0.38±0.04). However, it was interesting to observe a three-fold increase of the De value for FF-PEI-R440 (De/D0=1.23±0.08). It is considered that the occurrence of the drastic uptake rate increase in FF-PEI-R440 was attributed to the decreased available binding sites for protein molecule, which led to the decrease of binding strength, thus facilitated the happenings of “chain delivery” effect of bound proteins. Besides, a study on the effect of ionic strength clarified that the lower the IC value, the higher the sensitivity of protein binding to salt concentration due to the easily screened electrostatic interactions at low surface charge densities. The ionic strength at the elution peak also decreased with decreasing IC in accordance with the salt sensitivity order. Column breakthrough studies demonstrated that the dynamic adsorption capacity of FF-PEI-R440 was much higher than the other three resins at flow rates higher than 30cm/h because of its high uptake rate. The findings in this work provided new insights into the effects of the interactions between proteins and grafted polymers on adsorption equilibria and uptake kinetics, which would help the selection and design of suitable media for high-performance protein chromatography.

Viruses, stemness, embryogenesis, and cancer: a miracle leap toward molecular definition of novel oncotargets for therapy-resistant malignant tumors?

Recent breakthrough studies documented consistent activation of specific endogenous retroviruses in human embryonic stem cells and preimplantation human embryos and demonstrated the essential role of the sustained retroviral activities for maintenance of pluripotency and embryonic stem cell identity. Present analysis has led to the hypothesis that activation of the human stem cell-associated retroviruses (SCARs), namely LTR7/HERVH and LTR5_Hs/HERVK, is likely associated with the emergence of clinically lethal therapy resistant death-from-cancer phenotypes in a sub-set of cancer patients diagnosed with different types of malignant tumors.

Correction to Carbon Dioxide Separation from Nitrogen/Hydrogen Mixtures over Activated Carbon Beads: Adsorption Isotherms and Breakthrough Studies

ADVERTISEMENT RETURN TO ISSUEPREVAddition/CorrectionORIGINAL ARTICLEThis notice is a correctionCorrection to Carbon Dioxide Separation from Nitrogen/Hydrogen Mixtures over Activated Carbon Beads: Adsorption Isotherms and Breakthrough StudiesSimon J. Caldwell, Bushra Al-Duri, Nannan Sun, Cheng-gong Sun, Hao Liu, Colin E. Snape, Kaixi Li, and Joseph Wood*Cite this: Energy Fuels 2015, 29, 7, 4666Publication Date (Web):June 25, 2015Publication History Published online25 June 2015Published inissue 16 July 2015https://doi.org/10.1021/acs.energyfuels.5b01372Copyright © 2015 American Chemical SocietyRIGHTS & PERMISSIONSArticle Views433Altmetric-Citations1LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (106 KB) Get e-Alerts Get e-Alerts

Intensification of ammonia removal from waste water in biologically active zeolitic ion exchange columns

The use of nitrification filters for the removal of ammonium ion from waste-water is an established technology deployed extensively in municipal water treatment, in industrial water treatment and in applications such as fish farming. The process involves the development of immobilized bacterial films on a solid packing support, which is designed to provide a suitable host for the film, and allow supply of oxygen to promote aerobic action. Removal of ammonia and nitrite is increasingly necessary to meet drinking water and discharge standards being applied in the US, Europe and other places. Ion-exchange techniques are also effective for removal of ammonia (as the ammonium ion) from waste water and have the advantage of fast start-up times compared to biological filtration which in some cases may take several weeks to be fully operational. Here we explore the performance of ion exchange columns in which nitrifying bacteria are cultivated, with the goal of a “combined” process involving simultaneous ion-exchange and nitrification, intensified by in-situ aeration with a novel membrane module. There were three experimental goals. Firstly, ion exchange zeolites were characterized and prepared for comparative column breakthrough studies for ammonia removal. Secondly effective in-situ aeration for promotion of nitrifying bacterial growth was studied using a number of different membranes including polyethersulfone (PES), polypropylene (PP), nylon, and polytetra-fluoroethylene (PTFE). Thirdly the breakthrough performance of ion exchange columns filled with zeolite in the presence of aeration and in the presence of nitrifying bacteria was determined to establish the influence of biomass, and aeration upon breakthrough during ammonium ion uptake.The methodology adopted included screening of two types of the naturally occuring zeolite clinoptilolite for effective ammonia removal in continuous ion-exchange columns. Next, the performance of fixed beds of clinoptilolite in the presence of nitrifying bacteria is compared to that in columns in which only ion exchange is occurring. The aeration performance of each of the chosen membranes was compared experimentally using a newly developed membrane support module which is also described. Comparison of ammonia removal in columns equipped with in-situ aeration using each membrane was undertaken and the breakthrough characteristics determined. The results showed that ammonia removal in the presence of the nitrifiers was significantly intensified. Column operation with membrane aeration showed further enhancement of ammonia removal. The greatest enhancement was observed in the case of the polyethersulfone membrane (PES). It is concluded that combined nitrification and ion-exchange is significantly intensified in packed columns by in-situ aeration using a novel membrane module. There is significant potential for extending the ion-exchange cycle time and thus potential cost reduction.