114 research outputs found
Novel advanced solvent-based carbon capture pilot demonstration
ION Engineering’s advanced solvent is one of the leading second generation solvent systems currently under development for post-combustion carbon dioxide (CO2) capture. Throughout small scale pilot testing with coal and natural gas fired flue gas, bench scale pilot and laboratory testing, ION’s advanced solvent has consistently demonstrated 30+% reductions in regeneration energy requirements in comparison to traditional aqueous monoethanolamine (Aq-MEA). These results, in addition to CO2 solvent carrying capacities 35% higher than Aq-MEA and significantly less solvent degradation, demonstrate that ION’s CO2 capture technology has the potential to significantly reduce both capital and operating costs.
ION Engineering has recently completed a 0.6 Megawatts electric (MWe) Slipstream Pilot demonstration, at the National Carbon Capture Center (NCCC) located at Southern Company’s Plant Gaston in Wilsonville, Alabama. The NCCC test facility utilizes a flue gas slipstream up to a maximum of 6,000 lb/hr from a commercially dispatched base-loaded 880-MW coal-fired boiler which supplies the NCCC test facilities. On-site work began in April 2015, with testing completed from mid-June to mid-August 2015. The overall objectives of this project are to advance ION’s solvent-based CO2 capture process at the equivalent of approximately 0.6 MWe scale pilot in order to meet the Department of Energy’s (DOE) goal for second generation solvents of ≥ 90% CO2 capture rate with 95% CO2 purity at a cost of \u3c $40/tonne CO2 captured by 2025. Additional objectives included: validation of ION’s solvent specific simulation capabilities, completion of 1,000 hours of continuous testing and an assessment of solvent lifetime.
The NCCC results indicate that ION is making substantial progress towards DOE’s goals for second generation solvents. Total test hours for the program exceeded 1,100 hours. ION has also validated its solvent specific ProTreat® simulation models during parametric and steady state testing and the analyses of solvent samples for solvent lifetime studies are still in progress. Additionally, ION demonstrated that it can successfully operate its advanced solvent in a pilot unit designed for traditional Aq-MEA solvent with minimal pilot modifications. Throughout pilot testing at NCCC, ION confirmed its understanding of process improvements and analytics that will enable successful operation of its advanced solvent at significantly lower L/G circulation rates and regeneration energies.
ION is currently working with national and international partners to further demonstrate its carbon capture technology in real process environments and multiple commercial settings. The data gathered from this test campaign conducted at NCCC continues to strengthen ION’s solvent technology and positive track record in executing off site test campaigns. ION anticipates that the recently completed pilot scale test at NCCC along with future projects will directly impact the state of the art of CO2 solvent technologies and facilitate advancement of CO2 capture towards commercialization and implementation of ION technology
Complementary and Integrative Health Lexicon (CIHLex) and Entity Recognition in the Literature
Objective: Our study aimed to construct an exhaustive Complementary and
Integrative Health (CIH) Lexicon (CIHLex) to better represent the often
underrepresented physical and psychological CIH approaches in standard
terminologies. We also intended to apply advanced Natural Language Processing
(NLP) models such as Bidirectional Encoder Representations from Transformers
(BERT) and GPT-3.5 Turbo for CIH named entity recognition, evaluating their
performance against established models like MetaMap and CLAMP. Materials and
Methods: We constructed the CIHLex by integrating various resources, compiling
and integrating data from biomedical literature and relevant knowledge bases.
The Lexicon encompasses 198 unique concepts with 1090 corresponding unique
terms. We matched these concepts to the Unified Medical Language System (UMLS).
Additionally, we developed and utilized BERT models and compared their
efficiency in CIH named entity recognition to that of other models such as
MetaMap, CLAMP, and GPT3.5-turbo. Results: From the 198 unique concepts in
CIHLex, 62.1% could be matched to at least one term in the UMLS. Moreover,
75.7% of the mapped UMLS Concept Unique Identifiers (CUIs) were categorized as
"Therapeutic or Preventive Procedure." Among the models applied to CIH named
entity recognition, BLUEBERT delivered the highest macro average F1-score of
0.90, surpassing other models. Conclusion: Our CIHLex significantly augments
representation of CIH approaches in biomedical literature. Demonstrating the
utility of advanced NLP models, BERT notably excelled in CIH entity
recognition. These results highlight promising strategies for enhancing
standardization and recognition of CIH terminology in biomedical contexts
Reverberation Mapping of the Kepler-Field AGN KA1858+4850
KA1858+4850 is a narrow-line Seyfert 1 galaxy at redshift 0.078 and is among
the brightest active galaxies monitored by the Kepler mission. We have carried
out a reverberation mapping campaign designed to measure the broad-line region
size and estimate the mass of the black hole in this galaxy. We obtained 74
epochs of spectroscopic data using the Kast Spectrograph at the Lick 3-m
telescope from February to November of 2012, and obtained complementary V-band
images from five other ground-based telescopes. We measured the H-beta light
curve lag with respect to the V-band continuum light curve using both
cross-correlation techniques (CCF) and continuum light curve variability
modeling with the JAVELIN method, and found rest-frame lags of lag_CCF = 13.53
(+2.03, -2.32) days and lag_JAVELIN = 13.15 (+1.08, -1.00) days. The H-beta
root-mean-square line profile has a width of sigma_line = 770 +/- 49 km/s.
Combining these two results and assuming a virial scale factor of f = 5.13, we
obtained a virial estimate of M_BH = 8.06 (+1.59, -1.72) x 10^6 M_sun for the
mass of the central black hole and an Eddington ratio of L/L_Edd ~ 0.2. We also
obtained consistent but slightly shorter emission-line lags with respect to the
Kepler light curve. Thanks to the Kepler mission, the light curve of
KA1858+4850 has among the highest cadences and signal-to-noise ratios ever
measured for an active galactic nucleus; thus, our black hole mass measurement
will serve as a reference point for relations between black hole mass and
continuum variability characteristics in active galactic nuclei
Ventricular pacing or dual-chamber pacing for sinus-node dysfunction
BACKGROUND
Dual-chamber (atrioventricular) and single-chamber (ventricular) pacing are alternative treatment approaches for sinus-node dysfunction that causes clinically significant bradycardia. However, it is unknown which type of pacing results in the better outcome. METHODS
We randomly assigned a total of 2010 patients with sinus-node dysfunction to dual-chamber pacing (1014 patients) or ventricular pacing (996 patients) and followed them for a median of 33.1 months. The primary end point was death from any cause or nonfatal stroke. Secondary end points included the composite of death, stroke, or hospitalization for heart failure; atrial fibrillation; heart-failure score; the pacemaker syndrome; and the quality of life. RESULTS
The incidence of the primary end point did not differ significantly between the dual-chamber group (21.5 percent) and the ventricular-paced group (23.0 percent, P=0.48). In patients assigned to dual-chamber pacing, the risk of atrial fibrillation was lower (hazard ratio, 0.79; 95 percent confidence interval, 0.66 to 0.94; P=0.008), and heart-failure scores were better (P CONCLUSIONS
In sinus-node dysfunction, dual-chamber pacing does not improve stroke-free survival, as compared with ventricular pacing. However, dual-chamber pacing reduces the risk of atrial fibrillation, reduces signs and symptoms of heart failure, and slightly improves the quality of life. Overall, dual-chamber pacing offers significant improvement as compared with ventricular pacing
The Most Slowly Declining Type Ia Supernova 2001ay
We present optical and near-infrared photometry, as well as ground-based
optical spectra and Hubble Space Telescope ultraviolet spectra, of the Type Ia
supernova (SN) 2001ay. At maximum light the Si II and Mg II lines indicated
expansion velocities of 14,000 km/sec, while Si III and S II showed velocities
of 9,000 km/sec There is also evidence for some unburned carbon at 12,000
km/sec. SN 2001ay exhibited a decline-rate parameter Delta m_15(B) = 0.68 \pm
0.05 mag; this and the B-band photometry at t > +25 d past maximum make it the
most slowly declining Type Ia SN yet discovered. Three of four
super-Chandrasekhar-mass candidates have decline rates almost as slow as this.
After correction for Galactic and host-galaxy extinction, SN 2001ay had M_B =
-19.19 and M_V = -19.17 mag at maximum light; thus, it was not overluminous in
optical bands. In near-infrared bands it was overluminous only at the 2-sigma
level at most. For a rise time of 18 d (explosion to bolometric maximum) the
implied Ni-56 yield was (0.58 \pm 0.15)/alpha M_Sun, with alpha = L_max/E_Ni
probably in the range 1.0 to 1.2. The Ni-56 yield is comparable to that of many
Type Ia supernovae. The "normal" Ni-56 yield and the typical peak optical
brightness suggest that the very broad optical light curve is explained by the
trapping of the gamma rays in the inner regions.Comment: 57 pages, 22 figures. To be published in the Astronomical Journal
(September 2011
A Cross-Study Transcriptional Analysis of Parkinson's Disease
The study of Parkinson's disease (PD), like other complex neurodegenerative disorders, is limited by access to brain tissue from patients with a confirmed diagnosis. Alternatively the study of peripheral tissues may offer some insight into the molecular basis of disease susceptibility and progression, but this approach still relies on brain tissue to benchmark relevant molecular changes against. Several studies have reported whole-genome expression profiling in post-mortem brain but reported concordance between these analyses is lacking. Here we apply a standardised pathway analysis to seven independent case-control studies, and demonstrate increased concordance between data sets. Moreover data convergence increased when the analysis was limited to the five substantia nigra (SN) data sets; this highlighted the down regulation of dopamine receptor signaling and insulin-like growth factor 1 (IGF1) signaling pathways. We also show that case-control comparisons of affected post mortem brain tissue are more likely to reflect terminal cytoarchitectural differences rather than primary pathogenic mechanisms. The implementation of a correction factor for dopaminergic neuronal loss predictably resulted in the loss of significance of the dopamine signaling pathway while axon guidance pathways increased in significance. Interestingly the IGF1 signaling pathway was also over-represented when data from non-SN areas, unaffected or only terminally affected in PD, were considered. Our findings suggest that there is greater concordance in PD whole-genome expression profiling when standardised pathway membership rather than ranked gene list is used for comparison
Using lithium as a neuroprotective agent in patients with cancer
Neurocognitive impairment is being increasingly recognized as an important issue in patients with cancer who develop cognitive difficulties either as part of direct or indirect involvement of the nervous system or as a consequence of either chemotherapy-related or radiotherapy-related complications. Brain radiotherapy in particular can lead to significant cognitive defects. Neurocognitive decline adversely affects quality of life, meaningful employment, and even simple daily activities. Neuroprotection may be a viable and realistic goal in preventing neurocognitive sequelae in these patients, especially in the setting of cranial irradiation. Lithium is an agent that has been in use for psychiatric disorders for decades, but recently there has been emerging evidence that it can have a neuroprotective effect.This review discusses neurocognitive impairment in patients with cancer and the potential for investigating the use of lithium as a neuroprotectant in such patients.<br /
Whole exome re-sequencing implicates CCDC38 and cilia structure and function in resistance to smoking related airflow obstruction
Chronic obstructive pulmonary disease (COPD) is a leading cause of global morbidity and mortality and, whilst smoking remains the single most important risk factor, COPD risk is heritable. Of 26 independent genomic regions showing association with lung function in genome-wide association studies, eleven have been reported to show association with airflow obstruction. Although the main risk factor for COPD is smoking, some individuals are observed to have a high forced expired volume in 1 second (FEV1) despite many years of heavy smoking. We # hypothesised that these ‘‘resistant smokers’’ may harbour variants which protect against lung function decline caused by smoking and provide insight into the genetic determinants of lung health. We undertook whole exome re sequencing of 100 heavy smokers who had healthy lung function given their age, sex, height and smoking history and applied three complementary approaches to explore the genetic architecture of smoking resistance. Firstly, we identified novel functional variants in the ‘‘resistant smokers’’ and looked for enrichment of these novel variants within biological pathways. Secondly, we undertook association testing of all exonic variants individually with two independent control sets. Thirdly, we undertook gene-based association testing of all exonic variants. Our strongest signal of association with smoking resistance for a non-synonymous SNP was for rs10859974 (P = 2.3461024) in CCDC38, a gene which has previously been reported to show association with FEV1/FVC, and we demonstrate moderate expression of CCDC38 in bronchial epithelial cells. We identified an enrichment of novel putatively functional variants in genes related to cilia structure and function in resistant smokers. Ciliary function abnormalities are known to be associated with both smoking and reduced mucociliary clearance in patients with COPD. We suggest that genetic influences on the development or function of cilia in the bronchial epithelium may affect growth of cilia or the extent of damage caused by tobacco smoke
Using lithium as a neuroprotective agent in patients with cancer
Neurocognitive impairment is being increasingly recognized as an important issue in patients with cancer who develop cognitive difficulties either as part of direct or indirect involvement of the nervous system or as a consequence of either chemotherapy-related or radiotherapy-related complications. Brain radiotherapy in particular can lead to significant cognitive defects. Neurocognitive decline adversely affects quality of life, meaningful employment, and even simple daily activities. Neuroprotection may be a viable and realistic goal in preventing neurocognitive sequelae in these patients, especially in the setting of cranial irradiation. Lithium is an agent that has been in use for psychiatric disorders for decades, but recently there has been emerging evidence that it can have a neuroprotective effect.This review discusses neurocognitive impairment in patients with cancer and the potential for investigating the use of lithium as a neuroprotectant in such patients.<br /
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