Development and Performance Evaluation of an Innovative Anti-Biofouling Reverse Osmosis Membrane for Water Purification Applications

Biofouling is a main operational problem plaguing membrane use in the water purification industry. Biofouling limits water productivity, water quality, membrane life, and increases operational costs. Therefore, developing an effective, widely applicable technology to control biofouling would facilitate membrane implementation and enable efficient use of membrane technology. Accordingly, the overall goal of this dissertation was to develop and evaluate the performance of a novel anti-biofouling reverse osmosis (RO) membrane(s) with 2-aminoimidazoles (2-AIs) incorporated as the active compound. 2-AIs are non-biocidal, bioactive compounds that actively disrupt biofilm formation mechanisms. 2-AIs are unique because they are one of the only compound classes that actively disrupts biofilm formation across different bacteria phyla, classes, and orders. To achieve the overall goal, the following specific objectives were met: (1) to develop an anti-biofouling water purification membrane(s) through 2-AI incorporation into active layers of commercially available RO membranes, (2) to develop an anti-biofouling water purification membrane(s) through 2-AI incorporation into active layers of RO membranes during active layer casting, (3) to characterize 2-AI membrane(s) performance in terms of biofouling inhibition, water productivity, and contaminant removal. Experimental results led to the following conclusions: (i) 2-AI membranes significantly inhibited Pseudomonas aeruginosa biofilms by 39-96% (p=0.002-0.12) due to the presence of 2-AI and not changes in membrane physico-chemical properties. (ii) Compared to (2-AI lacking) control membranes, 2-AI incorporation decreased initial membrane water permeability by 0-44% and salt rejection by -0.4-4.3 percentage points, without efforts to optimize these parameters. (iii) Incorporating 2-AI into active layers of commercial RO membranes by activating carboxylic acid groups with 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide produced a more effective membrane than incorporating 2-AI during active layer casting. (iv) Under operationally realistic conditions (e.g., using cross-flow and real waters), biofilm formation was significantly inhibited (98%, p<0.001) by 2-AI membranes; and when biofilm formation was a fouling mechanism, 2-AI membranes had higher water permeability (10-11%) and organics rejection (11-12 percentage points) than (2-AI-lacking) control membranes. Overall, this work constitutes the proof-of-concept for 2-AI membranes and 2-AI incorporation represents a promising, novel enhancement for biofouling prevention and control. Based on these results, further 2-AI membrane optimization and performance testing is warranted.Doctor of Philosoph

Towards Computational Persuasion via Natural Language Argumentation Dialogues

Computational persuasion aims to capture the human ability to persuade through argumentation for applications such as behaviour change in healthcare (e.g. persuading people to take more exercise or eat more healthily). In this paper, we review research in computational persuasion that incorporates domain modelling (capturing arguments and counterarguments that can appear in a persuasion dialogues), user modelling (capturing the beliefs and concerns of the persuadee), and dialogue strategies (choosing the best moves for the persuader to maximize the chances that the persuadee is persuaded). We discuss evaluation of prototype systems that get the user’s counterarguments by allowing them to select them from a menu. Then we consider how this work might be enhanced by incorporating a natural language interface in the form of an argumentative chatbot

Omega-3 supplementation in patients with sepsis: a systematic review and meta-analysis of randomized trials.

BACKGROUND: Nutritional supplementation of omega-3 fatty acids has been proposed to modulate the balance of pro- and anti-inflammatory mediators in sepsis. If proved to improve clinical outcomes in critically ill patients with sepsis, this intervention would be easy to implement. However, the cumulative evidence from several randomized clinical trials (RCTs) remains unclear. METHODS: We searched the Cochrane Library, MEDLINE, and EMBASE through December 2016 for RCTs on parenteral or enteral omega-3 supplementation in adult critically ill patients diagnosed with sepsis or septic shock. We analysed the included studies for mortality, intensive care unit (ICU) length of stay, and duration of mechanical ventilation, and used the Grading of Recommendations Assessment, Development and Evaluation approach to assess the quality of the evidence for each outcome. RESULTS: A total of 17 RCTs enrolling 1239 patients met our inclusion criteria. Omega-3 supplementation compared to no supplementation or placebo had no significant effect on mortality [relative risk (RR) 0.85; 95% confidence interval (CI) 0.71, 1.03; P = 0.10; I (2) = 0%; moderate quality], but significantly reduced ICU length of stay [mean difference (MD) -3.79 days; 95% CI -5.49, -2.09; P < 0.0001, I (2) = 82%; very low quality] and duration of mechanical ventilation (MD -2.27 days; 95% CI -4.27, -0.27; P = 0.03, I (2) = 60%; very low quality). However, sensitivity analyses challenged the robustness of these results. CONCLUSION: Omega-3 nutritional supplementation may reduce ICU length of stay and duration of mechanical ventilation without significantly affecting mortality, but the very low quality of overall evidence is insufficient to justify the routine use of omega-3 fatty acids in the management of sepsis

Significant benefits of AIP testing and clinical screening in familial isolated and young-onset pituitary tumors

Context Germline mutations in the aryl hydrocarbon receptor-interacting protein (AIP) gene are responsible for a subset of familial isolated pituitary adenoma (FIPA) cases and sporadic pituitary neuroendocrine tumors (PitNETs). Objective To compare prospectively diagnosed AIP mutation-positive (AIPmut) PitNET patients with clinically presenting patients and to compare the clinical characteristics of AIPmut and AIPneg PitNET patients. Design 12-year prospective, observational study. Participants & Setting We studied probands and family members of FIPA kindreds and sporadic patients with disease onset ≤18 years or macroadenomas with onset ≤30 years (n = 1477). This was a collaborative study conducted at referral centers for pituitary diseases. Interventions & Outcome AIP testing and clinical screening for pituitary disease. Comparison of characteristics of prospectively diagnosed (n = 22) vs clinically presenting AIPmut PitNET patients (n = 145), and AIPmut (n = 167) vs AIPneg PitNET patients (n = 1310). Results Prospectively diagnosed AIPmut PitNET patients had smaller lesions with less suprasellar extension or cavernous sinus invasion and required fewer treatments with fewer operations and no radiotherapy compared with clinically presenting cases; there were fewer cases with active disease and hypopituitarism at last follow-up. When comparing AIPmut and AIPneg cases, AIPmut patients were more often males, younger, more often had GH excess, pituitary apoplexy, suprasellar extension, and more patients required multimodal therapy, including radiotherapy. AIPmut patients (n = 136) with GH excess were taller than AIPneg counterparts (n = 650). Conclusions Prospectively diagnosed AIPmut patients show better outcomes than clinically presenting cases, demonstrating the benefits of genetic and clinical screening. AIP-related pituitary disease has a wide spectrum ranging from aggressively growing lesions to stable or indolent disease course

The Eleventh and Twelfth Data Releases of the Sloan Digital Sky Survey: Final Data from SDSS-III

The third generation of the Sloan Digital Sky Survey (SDSS-III) took data from 2008 to 2014 using the original SDSS wide-field imager, the original and an upgraded multi-object fiber-fed optical spectrograph, a new near-infrared high-resolution spectrograph, and a novel optical interferometer. All of the data from SDSS-III are now made public. In particular, this paper describes Data Release 11 (DR11) including all data acquired through 2013 July, and Data Release 12 (DR12) adding data acquired through 2014 July (including all data included in previous data releases), marking the end of SDSS-III observing. Relative to our previous public release (DR10), DR12 adds one million new spectra of galaxies and quasars from the Baryon Oscillation Spectroscopic Survey (BOSS) over an additional 3000 deg2 of sky, more than triples the number of H-band spectra of stars as part of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE), and includes repeated accurate radial velocity measurements of 5500 stars from the Multi-object APO Radial Velocity Exoplanet Large-area Survey (MARVELS). The APOGEE outputs now include the measured abundances of 15 different elements for each star. In total, SDSS-III added 5200 deg2 of ugriz imaging; 155,520 spectra of 138,099 stars as part of the Sloan Exploration of Galactic Understanding and Evolution 2 (SEGUE-2) survey; 2,497,484 BOSS spectra of 1,372,737 galaxies, 294,512 quasars, and 247,216 stars over 9376 deg2; 618,080 APOGEE spectra of 156,593 stars; and 197,040 MARVELS spectra of 5513 stars. Since its first light in 1998, SDSS has imaged over 1/3 of the Celestial sphere in five bands and obtained over five million astronomical spectra. \ua9 2015. The American Astronomical Society