Design of Prototype Monolithic Aerogel Catalytic Converter

Internal combustion engines utilize catalytic converters to combat the production of toxic compounds found in car exhaust, such as nitrogen oxides, carbon monoxide, and hydrocarbons, by converting them to more environmentally friendly gasses, such as carbon dioxide, water vapor, and nitrogen gas. Aerogels\u27 high porosity and high surface area, as well as the ability to maintain textural stability at high temperatures, make them good candidates for heterogeneous catalysis applications. Past research in the Union College Aerogel Lab has shown that the catalytic performance of granular or powdered aerogels can be augmented by adding metal salts in the synthesis process. Unfortunately, free-standing granular aerogels would be an unaccommodating substitute for traditional catalytic converters as they are difficult to contain. While the low-difficulty, low-cost pathway into the commercialization of aerogel catalytic converters is through the introduction of aerogels into the conventional wash-coating process used to coat the catalytic converter substrate with a catalyst material, monolithic models may prove to be more feasible to produce and more effective at improving the catalysis of automotive emissions. Aerogels have high surface areas and are very porous, however, the rate of diffusion of gases through a monolithic aerogel is not suitable for use in a catalytic converter. The purpose of this research is to develop an aerogel catalytic converter prototype, and by doing so accomplish three things: 1) create multiple monolithic aerogel substrate models; 2) quantitatively compare the substrate models against each other to prescribe the most effective model; 3) and lastly, test the catalytic performance of the model when doped with catalytic metals. Five inert substrate models were created, and the model with the most reproducibility and mechanical stability under flow conditions was the laser cut two sides lined up model. This model was then doped with heat treated copper alumina aerogel granules and catalytically tested. While the catalytic testing showed that the first monolithic catalytic aerogel substrate iteration was inert when compared to previous union college granular catalytic aerogels, promising future iterations arose that could make monolithic catalytic converter substrates feasible

Conformal properties of hyperinvariant tensor networks

We thank Santiago Oviedo-Casado, Javier Molina-Vilaplana, Matthias Volk, Sukhbinder Singh, and Michael Kastoryano for insightful discussions, as well as Alexander Jahn, Jens Eisert and Glen Evenbly for their feedback on the manuscript. J.P. is grateful for financial support from Ministerio de Ciencia, Innovación y Universidades (SPAIN), including FEDER (Grant no. PGC2018-097328-B-100) together with Fundación Séneca (Murcia, Spain) (Project no. 19882/GERM/15).M.S. wrote the main manuscript text. J.P. supervised and reviewed the manuscript.Hyperinvariant tensor networks (hyMERA) were introduced as a way to combine the successes of perfect tensor networks (HaPPY) and the multiscale entanglement renormalization ansatz (MERA) in simulations of the AdS/CFT correspondence. Although this new class of tensor network shows much potential for simulating conformal field theories arising from hyperbolic bulk manifolds with quasiperiodic boundaries, many issues are unresolved. In this manuscript we analyze the challenges related to optimizing tensors in a hyMERA with respect to some quasiperiodic critical spin chain, and compare with standard approaches in MERA. Additionally, we show two new sets of tensor decompositions which exhibit different properties from the original construction, implying that the multitensor constraints are neither unique, nor difficult to find, and that a generalization of the analytical tensor forms used up until now may exist. Lastly, we perform randomized trials using a descending superoperator with several of the investigated tensor decompositions, and find that the constraints imposed on the spectra of local descending superoperators in hyMERA are compatible with the operator spectra of several minimial model CFTs.SPAINFundación Séneca 19882/GERM/15Ministerio de Ciencia, Innovación y UniversidadesEuropean Regional Development Fund PGC2018-097328-B-10

Feasibility studies for a trial of septal resection to prevent subfertility and miscarriage

Introduction Congenital uterine anomalies result from the abnormal embryological development of the paramesonephric (Müllerian) ducts. Debate surrounding their classification is ongoing. During this PhD project both the American Society for Reproductive Medicine and The European Society of Human Reproduction and Embryology (ESHRE) with the European Society for Gynaecological Endoscopy (ESGE) have published different classification systems. To adequately assess uterine morphology requires concurrent imaging of the external and internal contours of the uterus. Three-dimensional ultrasound can achieve this view and is more acceptable to women than more invasive tests. In view of the inconsistent classification systems and use of various diagnostic tests data regarding prevalence and effect on reproductive outcome must be interpreted cautiously. Nonetheless, it appears that uterine septa are more prevalent in women with poor reproductive outcomes and associated with infertility, miscarriage and preterm birth. The rationale for septal resection is to restore normal uterine anatomy with the intention of improving reproductive outcome. However all previous studies assessing the effect of septal resection are biased due to their observational design using women as their own controls. There have been no randomised controlled trials. Aims The aim was to investigate the hypothesis that a trial of septal resection for women with subfertility or miscarriage is feasible to conduct. Studies A non-invasive method for assessing uterine septa is a vital prerequisite for a trial, to allow women to be assessed properly and consented before an invasive operative hysteroscopy is done. Furthermore, a test is required to assess the efficacy of septal resection post-procedure as some women are left with a residual septum. So it was important to establish the diagnostic reliability of three-dimensional ultrasound to identify uterine septa. ESHRE recommended using three-dimensional ultrasound, but few data existed demonstrating its reliability. I conducted two reliability studies. The first found that the intra-rater reliability of experts in uterine anomalies was only moderate. This study was limited as it could not differentiate between the manipulation of uterine volumes, uterine measurements or application of classification systems. A second study assessed the intra- and inter-rater reliability of uterine measurements and then used algorithms to classify the volumes. This showed uterine measurements are highly reproducible with cavity indentation showing the highest intra- and inter-rater reliability (both ICC 0.98). Applying classification algorithms to these measurements showed almost perfect intra and inter-rater agreement. When designing a trial to definitively establish the efficacy of an intervention it is crucial to ensure it is adequately powered to detect a difference which is important to patients. So next I set out to calculate the minimum clinically important difference for women to consider septal resection. Using survey and interviews I calculated that the median minimum clinically important difference for women with a history of poor reproductive outcome was a change in future risk of miscarriage from 30% to 10%. The sample size required to detect this difference was 118, (59 in each arm) where _=0.05 and (1-_)=0.9. Between August 2014 and August 2017, 6035 women with subfertility and miscarriage were screened in three settings to identify those eligible to participate. Three-dimensional ultrasound was used as initial screening in a tertiary fertility clinic (n=2846) and recurrent miscarriage clinic (n=189). Around 3000 women underwent two-dimensional ultrasound in the early pregnancy unit, of which five had suspected uterine anomalies and were referred for three-dimensional ultrasound. A uterine septum was present in 15, of whom 13 were eligible to participate in the pilot septal resection trial. So identifying one eligible participant required approximately 464 women to be screened. Divided by patient population, to identify one eligible participant the number of women to be screened using three-dimensional ultrasound was 407 women with infertility, or 27 women with recurrent miscarriage. Approximately one septum was identified per 1500 women who had a two-dimensional scan in the early pregnancy unit. Subsequently I undertook three studies of the willingness of patients and clinicians to participate in the pilot trial. First I undertook a survey of clinicians. Sixty-seven clinicians responded and approximately half would randomise to a septal resection trial, but only 12 clinicians (18%) showed interest in becoming involved in such a trial. The next study investigated the willingness of eligible patients to participate. In Nottingham, 2 of 13 women were randomised to the study. A survey and interview with women who declined participation found that many had strong views on their treatment, either in favour of, or against resection and did not wish to leave it to chance. The third study assessed the willingness of other units to be involved in the trial. Twelve clinicians from eleven units expressed interest in becoming a trial site, but only one unit went on to randomise 4 further patients. Reasons for non-participation included lack of funding, exclusion from the NIHR Clinical Research Network Portfolio, inadequate access to three-dimensional ultrasound and local service configuration. During the study period six women were randomised. The final two chapters set out to establish if a septal resection trial is a research priority using two different methods. Firstly an economic evaluation and value-of-information analysis. Value of information is the amount a decision maker should be willing to pay for information prior to making a decision. As resources are finite, these methods can be used to direct future research efforts towards the most efficient studies. Septal resection, was compared with progesterone as a large study, the PROMISE trial, was recently funded. Using existing evidence, namely meta-analyses of biased studies, it predicted that there was no value in conducting further research into progesterone or septal resection as with existing evidence, they were both cost-effective interventions. Nonetheless, when more uncertainty was introduced based on expert opinion the value of information for both interventions increased. Using the most favourable assumptions for our present level of uncertainty, assuming the usual NHS value of £30,000 for a quality adjusted life year (QALY) the expected value over ten years to the NHS of the information from a progesterone trial was £1.6B compared with £80m for a septal resection trial. The main reason for this was that progesterone has a larger potential treatment population, all women with recurrent miscarriage, rather than just those with a uterine septum. Other trials are therefore a higher priority. Finally, I established the top research priorities for miscarriage. Miscarriage research uncertainties were identified and prioritised collaboratively by women and healthcare professionals. A priority setting partnership was conducted on the topic of miscarriage using methodology advocated by the James Lind Alliance, a subsidiary of NIHR. A total of 2402 unique questions were identified and refined to 58 summary questions. The top 10 research uncertainties were collaboratively agreed by women who have experienced miscarriage, those affected by miscarriage and healthcare professionals at a final workshop. The top question was “What are the effective interventions to prevent miscarriage, threatened miscarriage and recurrent miscarriage?”. This would include septal resection to prevent miscarriage, but would also be any other potential intervention. Discussion The high reliability of three-dimensional ultrasound to diagnose uterine septa was demonstrated. This was dependent on taking uterine measurements, as subjective application of any classification system is less reliable. The low prevalence of septa and the lack of willingness from patients and clinicians to participate would make a trial prohibitively time consuming or expensive. Furthermore, a uterine septum is not the condition for which resection is performed. Instead resection is to prevent infertility, miscarriage or preterm birth, meaning that ideally three separate trials should be performed. I demonstrated that funding a trial is unlikely to be the best use of resources as the cost of conducting a trial is high compared with the value of information it could provide to decision makers. However, patients and clinicians still consider further research in this area a priority. Herein lies the dilemma of whether to pursue a trial, which will provide the highest quality evidence but is likely infeasible, or to consider alternative methodology, albeit with limitations, to help guide women and their clinicians who are considering septal resection. Collaboration with other international groups is the only way to advance this trial further. For example, the Dutch TRUST trial. TRUST has also had difficult recruiting, but has randomised 43 women over nine years. A collaborative approach between the two studies may lead to the completion of a trial. Nonetheless, TRUST is not adequately powered to detect the minimum clinically important difference and has less stringent criteria for diagnosis of a uterine septum. Conclusion Presently, a randomised controlled trial of hysteroscopic septal resection for women with a history of subfertility or miscarriage and a uterine septum is not feasible. The reasons for this are that sufficient women and clinicians are not willing to participate to achieve the required sample size. Furthermore the resource required to recruit enough participants would make the trial prohibitively expensive

Canal seepage losses

Presented at Emerging challenges and opportunities for irrigation managers: energy, efficiency and infrastructure: a USCID water management conference held on April 26-29, 2011 in Albuquerque, New Mexico.Includes bibliographical references.Seepage from earthen irrigation canals represents substantial water loss in irrigation districts. Historically, the determination of canal seepage was accomplished using the inflow-outflow method with propeller and electromagnetic type flow meters. This method was difficult, time consuming, and limited by measurement device accuracy. In recent years, advances in technology have led to the widespread use of Acoustic Doppler Current Profilers (ADCP) for discharge measurements in streams and rivers. Even though ADCP use has become widespread for stream discharges, studies to determine canal seepage using this new technology are limited. Using an ADCP, extensive field measurements were conducted in the Middle Rio Grande Conservancy District. This paper describes the ADCP measurement protocol used to measure irrigation canal seepage and presents predictive equations for determining canal seepage based on flow rate and canal geometry

Narratives of therapeutic art-making in the context of marital breakdown: Older women reflect on a significant mid-life experience

This paper explores the narratives of three women aged 65-72 years. They reflected on an episode of therapeutic art-making in midlife, which addressed depression associated with marital crisis and breakdown. The narrative analysis focused upon on the ways in which participants narrated the events leading up to their participation in therapeutic art-making; the aspects of therapeutic art-making that continued to be given significance; the characters given primacy in the stories they told about their journey through therapy and marital breakdown; meanings, symbolic and otherwise, that participants ascribed to their artwork made during this turning point in their lives; and aspects of the narratives that conveyed present-day identities and artistic endeavors. The narratives revealed the complexity of the journey through marital breakdown and depression into health, and showed that therapeutic art-making could best be understood, not as a stand-alone experience, but as given meaning within the context of wider personal and social resources. Participants looked back on therapeutic art-making that occurred two decades earlier and still described this as a significant turning point in their personal development. Art as an adjunct to counselling/therapy was not only symbolically self-expressive but provided opportunity for decision-making, agency and a reformulated self-image

Characterization of Scale-Free Properties of Human Electrocorticography in Awake and Slow Wave Sleep States

Like many complex dynamic systems, the brain exhibits scale-free dynamics that follow power-law scaling. Broadband power spectral density (PSD) of brain electrical activity exhibits state-dependent power-law scaling with a log frequency exponent that varies across frequency ranges. Widely divergent naturally occurring neural states, awake and slow wave sleep (SWS), were used to evaluate the nature of changes in scale-free indices of brain electrical activity. We demonstrate two analytic approaches to characterizing electrocorticographic (ECoG) data obtained during awake and SWS states. A data-driven approach was used, characterizing all available frequency ranges. Using an equal error state discriminator (EESD), a single frequency range did not best characterize state across data from all six subjects, though the ability to distinguish awake and SWS ECoG data in individual subjects was excellent. Multi-segment piecewise linear fits were used to characterize scale-free slopes across the entire frequency range (0.2–200 Hz). These scale-free slopes differed between awake and SWS states across subjects, particularly at frequencies below 10 Hz and showed little difference at frequencies above 70 Hz. A multivariate maximum likelihood analysis (MMLA) method using the multi-segment slope indices successfully categorized ECoG data in most subjects, though individual variation was seen. In exploring the differences between awake and SWS ECoG data, these analytic techniques show that no change in a single frequency range best characterizes differences between these two divergent biological states. With increasing computational tractability, the use of scale-free slope values to characterize ECoG and EEG data will have practical value in clinical and research studies

Informatics and data mining tools and strategies for the Human Connectome Project

The Human Connectome Project (HCP) is a major endeavor that will acquire and analyze connectivity data plus other neuroimaging, behavioral, and genetic data from 1,200 healthy adults. It will serve as a key resource for the neuroscience research community, enabling discoveries of how the brain is wired and how it functions in different individuals. To fulfill its potential, the HCP consortium is developing an informatics platform that will handle: 1) storage of primary and processed data, 2) systematic processing and analysis of the data, 3) open access data sharing, and 4) mining and exploration of the data. This informatics platform will include two primary components. ConnectomeDB will provide database services for storing and distributing the data, as well as data analysis pipelines. Connectome Workbench will provide visualization and exploration capabilities. The platform will be based on standard data formats and provide an open set of application programming interfaces (APIs) that will facilitate broad utilization of the data and integration of HCP services into a variety of external applications. Primary and processed data generated by the HCP will be openly shared with the scientific community, and the informatics platform will be available under an open source license. This paper describes the HCP informatics platform as currently envisioned and places it into the context of the overall HCP vision and agenda