21 research outputs found
Reducing time to discovery : materials and molecular modeling, imaging, informatics, and integration
This work was supported by the KAIST-funded Global Singularity Research Program for 2019 and 2020. J.C.A. acknowledges support from the National Science Foundation under Grant TRIPODS + X:RES-1839234 and the Nano/Human Interfaces Presidential Initiative. S.V.K.’s effort was supported by the U.S. Department of Energy (DOE), Office of Science, Basic Energy Sciences (BES), Materials Sciences and Engineering Division and was performed at the Oak Ridge National Laboratory’s Center for Nanophase Materials Sciences (CNMS), a U.S. Department of Energy, Office of Science User Facility.Multiscale and multimodal imaging of material structures and properties provides solid ground on which materials theory and design can flourish. Recently, KAIST announced 10 flagship research fields, which include KAIST Materials Revolution: Materials and Molecular Modeling, Imaging, Informatics and Integration (M3I3). The M3I3 initiative aims to reduce the time for the discovery, design and development of materials based on elucidating multiscale processing-structure-property relationship and materials hierarchy, which are to be quantified and understood through a combination of machine learning and scientific insights. In this review, we begin by introducing recent progress on related initiatives around the globe, such as the Materials Genome Initiative (U.S.), Materials Informatics (U.S.), the Materials Project (U.S.), the Open Quantum Materials Database (U.S.), Materials Research by Information Integration Initiative (Japan), Novel Materials Discovery (E.U.), the NOMAD repository (E.U.), Materials Scientific Data Sharing Network (China), Vom Materials Zur Innovation (Germany), and Creative Materials Discovery (Korea), and discuss the role of multiscale materials and molecular imaging combined with machine learning in realizing the vision of M3I3. Specifically, microscopies using photons, electrons, and physical probes will be revisited with a focus on the multiscale structural hierarchy, as well as structure-property relationships. Additionally, data mining from the literature combined with machine learning will be shown to be more efficient in finding the future direction of materials structures with improved properties than the classical approach. Examples of materials for applications in energy and information will be reviewed and discussed. A case study on the development of a Ni-Co-Mn cathode materials illustrates M3I3's approach to creating libraries of multiscale structure-property-processing relationships. We end with a future outlook toward recent developments in the field of M3I3.Peer reviewe
An Assessment of the Secondary Neutron Dose in the Passive Scattering Proton Beam Facility of the National Cancer Center
The purpose of this study is to assess the additional neutron effective dose during passive scattering proton therapy. Monte Carlo code (Monte Carlo N-Particle 6) simulation was conducted based on a precise modeling of the National Cancer Center's proton therapy facility. A three-dimensional neutron effective dose profile of the interior of the treatment room was acquired via a computer simulation of the 217.8-MeV proton beam. Measurements were taken with a 3He neutron detector to support the simulation results, which were lower than the simulation results by 16% on average. The secondary photon dose was about 0.8% of the neutron dose. The dominant neutron source was deduced based on flux calculation. The secondary neutron effective dose per proton absorbed dose ranged from 4.942 ± 0.031 mSv/Gy at the end of the field to 0.324 ± 0.006 mSv/Gy at 150 cm in axial distance
Effects of temperature and pH on the biokinetic properties of thiocyanate biodegradation under autotrophic conditions
The simultaneous effects of temperature and pH on the biokinetic properties of thiocyanate biodegradation under mixed-culture, autotrophic conditions were investigated using response surface analysis (RSA) combined with biokinetic modeling. A partial cubic model, based on substrate inhibition biokinetics, was constructed for each kinetic coefficient in Andrew model (i.e., maximum specific growth rate (mu(m)), saturation coefficient (K-S), and substrate inhibition coefficient (K-SI)). Each model proved statistically reliable to approximate the responses of the kinetic coefficients to temperature and pH changes (r(2) > 0.8, p < 0.05). The response surface plots demonstrated that the biokinetic coefficients change with respect to temperature and pH significantly and in different ways. The model response surfaces were substantially different to each other, indicating distinct correlations between the independent (temperature and pH) and dependent (model response) variables in the models. Based on the estimated response surface models, temperature was shown to have significant effects on all biokinetic coefficients tested. A dominant influence of temperature on mu(m) response was observed while the interdependence of temperature and pH was apparent in the K-S and K-SI models. Specific growth rate (mu) versus substrate (i.e., thiocyanate) concentration plots simulating using the obtained response surface models confirmed the significant effects of temperature and pH on the microbial growth rate and therefore on the thiocyanate degradation rate. Overall, the response surface models able to describe the biokinetic effects of temperature and pH on thiocyanate biodegradation within the explored region (20-30 degrees C and pH 6.0-9.0) were successfully constructed and validated, providing fundamental information for better process control in thiocyanate treatment.close3
A comprehensive microbial insight into two-stage anaerobic digestion of food waste-recycling wastewater
Microbial community structures were assessed in a two-stage anaerobic digestion system treating food waste-recycling wastewater. The reactors were operated for 390 d at 10 different hydraulic retention times (HRTs) ranging from 25 to 4 d. Stable operation was achieved with the overall chemical oxygen demand (COD) removal efficiency of 73.0-85.9% at organic loading rate of up to 35.6 g COD/L.d. Performance of the acidogenic reactors, however, changed significantly during operation. This change coincided with transition of the bacterial community from one dominated by Aeriscardovia- and Lactobacillus amylovorus-related species to one dominated by Lactobacillus acetotolerans- and Lactobacillus kefiri-like organisms. In methanogenic reactors, the microbial community structures also changed at this stage along with the shift from Methanoculleus- to Methanosarcina-like organisms. This trend was confirmed by the non-metric multidimensional scaling joint plot of microbial shifts along with performance parameters. These results indicated that the overall process performance was relatively stable compared to the dynamic changes in the microbial structures and the acidogenic performance.close423
A theoretical and empirical investigation of gender and urban space The production and consumption of the built environment
In 2 vols.Available from British Library Document Supply Centre-DSC:DXN016646 / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo
Resource recovery using whey permeate to cultivate Phellinus linteus mycelium: Solid-state and submerged liquid fermentation
The growth characteristics of Phellinus linteus mycelium were assessed and compared under solid-state fermentation (SSF) and submerged liquid fermentation (SLF) systems on whey permeate medium. Response surface methodology was used to investigate the growth rates of mycelia under various conditions of operating temperature (T-O), initial pH, and substrate concentration ([S]). The optimal growth conditions of P. linteus mycelium were determined to be 26.1 degrees C, pH 4.6, and 60.3 g of lactose/L in the SSF system, and 29.0 degrees C, pH 5.0, and 65.3 g of lactose/L in the SLF system. The maximum growth rates were predicted to be 1.92 +/- 0.01 mm/d in SSF and 192.1 +/- 0.0 mg/L per day in SLF. Random trials were conducted to experimentally validate the evaluated optimal conditions. The differences between the modeled and observed values were only 5.3% in the SSF system and 6.1% in the SLF system. Significant engineering factors differed between the fermentation techniques; T-O was significant in both cultivation systems, whereas initial pH was significant in SSF but [51 was significant in SLF. Our findings can be used to guide the operation of the bioconversion process for cultivating P. linteus mycelium using whey permeate wastewater
Development of Chemiluminescence Resonance Test System Using SiPM Front-end ASIC to Detect Na and K Ions in Urine
The importance of measure and control dietary salinity arises to prevent and control the disease. There are several methods to measure the dietary salinities from blood or urine. The blood test is an accurate but inconvenient method because patients need to be at hospitals and wait for a longer time. Urine can be collected at home, and the test is more convenient. A 24-hour urine test is more accurate than random urine (RU) may cause more human errors. For this reason, testing RU accuracy for application will increase the convenience of patients. A SiPM sensor system to measure Guanine-based chemiluminescence resonance test light was developed. An ASIC system was developed and packaged to a chip. A test board for the packaged chip was developed. In parallel, the layout of an ASIC chip was assembled with SiPM and tested in the dark chamber to understand the functionality. The ASIC chip was tested in various frequencies with the test board. At the target frequency, the ASIC chip achieved 870 gain, which is exceeding the goal of 100. The SiPM system was measured with an oscilloscope, and the output signal was as expected. The performance test was done at a very high frequency (100MHz) and achieved 80.5% detection compared to the original light source signal. The ASIC chip development was successful, and SiPM matched the specification of the target operation
Bacteria and archaea communities in full-scale thermophilic and mesophilic anaerobic digesters treating food Wastewater: Key process parameters andmicrobial indicators of process instability
In this study, four different mesophilic and thermophilic full-scale anaerobic digesters treating food wastewater(FWW) were monitored for 1–2 years in order to investigate: 1) microbial communities underpinning anaerobicdigestion of FWW, 2) significant factors shaping microbial community structures, and 3) potential microbialindicators of process instability. Twenty-seven bacterial genera were identified as abundant bacteria underpinningthe anaerobic digestion of FWW. Methanosaeta harundinacea, M. concilii, Methanoculleus bourgensis, M.thermophilus, and Methanobacterium beijingense were revealed as dominant methanogens. Bacterial communitystructures were clearly differentiated by digesters; archaeal community structures of each digester were dominatedby one or two methanogen species. Temperature, ammonia, propionate, Na+, and acetate in the digesterwere significant factors shaping microbial community structures. The total microbial populations, microbialdiversity, and specific bacteria genera showed potential as indicators of process instability in the anaerobicdigestion of FWW.1
A comparative study on the process efficiencies and microbial community structures of six full-scale wet and semi-dry anaerobic digesters treating food wastes
The purpose of this study was to investigate the effect of different types of food wastes on the process efficiencyand microbial community structures in full-scale anaerobic digesters and to identify parameters that affect thesecriteria. Six full-scale anaerobic digesters were investigated; three were operated under “wet” condition (totalsolids TS ≤10%), and three were run under “semi-dry” condition (10% ≤TS ≤20%). Removal efficiency ofvolatile solids was much higher in the wet digesters (75.2 ± 3.8%) than in the semi-dry digesters(42.6 ± 5.5%). The bacterial and archaeal communities were distinctly characterized by familiesPorphyromonadaceae, Sphingobacteriaceae, Syntrophomonadaceae, and Methanobacteriaceae in the wet digesters;and of Clostridiaceae, Patulibacteraceae, Pseudonocardiaceae, Lachnospiraceae, Rikenellaceae, andMethanomicrobiaceae in the semi-dry digesters. The discriminant parameters identified were TS content ofinfluent, concentration of total ammonia nitrogen and the ratio of soluble chemical oxygen demand (COD) toCOD in the digester.The purpose of this study was to investigate the effect of different types of food wastes on the process efficiencyand microbial community structures in full-scale anaerobic digesters and to identify parameters that affect thesecriteria. Six full-scale anaerobic digesters were investigated; three were operated under “wet” condition (totalsolids TS ≤10%), and three were run under “semi-dry” condition (10% ≤TS ≤20%). Removal efficiency ofvolatile solids was much higher in the wet digesters (75.2 ± 3.8%) than in the semi-dry digesters(42.6 ± 5.5%). The bacterial and archaeal communities were distinctly characterized by familiesPorphyromonadaceae, Sphingobacteriaceae, Syntrophomonadaceae, and Methanobacteriaceae in the wet digesters;and of Clostridiaceae, Patulibacteraceae, Pseudonocardiaceae, Lachnospiraceae, Rikenellaceae, andMethanomicrobiaceae in the semi-dry digesters. The discriminant parameters identified were TS content ofinfluent, concentration of total ammonia nitrogen and the ratio of soluble chemical oxygen demand (COD) toCOD in the digester.1
Common key acidogen populations in anaerobic reactors treating different wastewaters: Molecular identification and quantitative monitoring
Bacterial population dynamics during the start-up of three lab-scale anaerobic reactors treating different wastewaters, i.e., synthetic glucose wastewater, whey permeate, and liquefied sewage sludge, were assessed using a combination of denaturing gradient gel electrophoresis (DGGE) and real-time PCR techniques. The DGGE results showed that bacterial populations related to Aeromonas spp. and Clostridium sticklandii emerged as common and prominent acidogens in all reactors. Two real-time PCR primer/probe sets targeting Aeromonas or C. sticklandii were developed, and successfully applied to quantitatively investigate their dynamics in relation to changes in reactor performance. Quantitative analysis demonstrated that both Aeromonas- and C. sticklandii-related populations were highly abundant for acidogenic period in all reactors. Aeromonas populations accounted for up to 86.6-95.3% of total bacterial 16S rRNA genes during start-up, suggesting that, given its capability of utilizing carbohydrate, Aeromonas is likely the major acidogen group responsible for the rapid initial fermentation of carbohydrate. C. sticklandii, able to utilize specific amino acids only, occupied up to 8.5-55.2% of total bacterial 16S rRNA genes in the reactors tested. Growth of this population is inferred to be supported, at least in part, by non-substrate amino acid sources like cell debris or extracellular excretions, particularly in the reactor fed on synthetic glucose wastewater with no amino acid source. The quantitative dynamics of the two acidogen groups of interest, together with their putative functions, suggest that Aeromonas and C. sticklandii populations were numerically as well as functionally important in all reactors tested, regardless of the differences in substrate composition. Particularly, the members of Aeromonas supposedly play vital roles in anaerobic digesters treating various substrates under acidogenic, fermentative start-up conditions.close11