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Electrochemical methods have been developed to measure metal ion concentrations in spent nuclear fuel electrorefiner by correlating concentration with current response. Analytes UCl3 and GdCl3 were studied in LiCl-KCl eutectic solvent at 773 K. A mixture matrix, which consisted of varying concentrations of UCl3 and GdCl3 from 1 to 10 wt% and from 1 to 3 wt%, respectively, was tested. Optimized normal pulse voltammetry (NPV) measurements were made on this mixture matrix and used for the concentration correlations. The accuracy of the prediction was improved by including solution resistance compensation and minimizing the working electrode surface area. The presence of GdCl3 showed no effect on the U3+ NPV reduction current, but high U concentrations affected the Gd3+ NPV reduction current. This is speculated to be due to increased migrational current in the molten salt mixture. The average relative measurement errors obtained were 1.6% and 2.7% for UCl3 and GdCl3 respectively.

In a molten salt nuclear reactor system, the redox potential must be controlled for mitigating corrosion of structural materials. The paper presented a critical review on the available knowledge of redox potential control in molten fluoride salt systems. The major phenomena that affect the redox potential and material corrosion are fission, TF production by transmutation, and salt contamination with metal fluorides or other oxidizing impurities. Redox potential control methodologies include gas sparging, contacting the salt with a reducing metal, and adding soluble salt redox buffers to the salt. Redox potential measurement technologies include electrochemical sensors and optical spectroscopy. The paper also analyzed the current technology issues and recommended near future studies.

TO THE EDITOR: Inherited thrombocytopenias are associated with bleeding of all types of severity depending on the reduction in platelet count and whether there is altered platelet function.[1][1] The normal range for platelet counts varies by up to threefold, but an individual’s platelet count is

Although next-generation sequencing technologies have accelerated the discovery of novel gene-to-disease associations, many patients with suspected Mendelian diseases still leave the clinic without a genetic diagnosis. An estimated one third of these patients will have disorders caused by mutations impacting splicing. RNA-sequencing has been shown to be a promising diagnostic tool, however few methods have been developed to integrate RNA-sequencing data into the diagnostic pipeline. Here, we introduce dasper, an R/Bioconductor package that improves upon existing tools for detecting aberrant splicing by using machine learning to incorporate disruptions in exon-exon junction counts as well as coverage. dasper is designed for diagnostics, providing a rank-based report of how aberrant each splicing event looks, as well as including visualization functionality to facilitate interpretation. We validate dasper using 16 patient-derived fibroblast cell lines harbouring pathogenic variants known to impact splicing. We find that dasper is able to detect pathogenic splicing events with greater accuracy than existing LeafCutterMD or z-score approaches. Furthermore, by only applying a broad OMIM gene filter (without any variant-level filters), dasper is able to detect pathogenic splicing events within the top 10 most aberrant identified for each patient. Since using publicly available control data minimises costs associated with incorporating RNA-sequencing into diagnostic pipelines, we also investigate the use of 504 GTEx fibroblast samples as controls. We find that dasper leverages publicly available data effectively, ranking pathogenic splicing events in the top 25. Thus, we believe dasper can increase diagnostic yield for a pathogenic splicing variants and enable the efficient implementation of RNA-sequencing for diagnostics in clinical laboratories.

Approximately 10% to 15% of patients with essential thrombocythemia (ET) lack the common driver mutations, so-called “triple-negative” (TN) disease. We undertook a systematic approach to investigate for somatic mutations and delineate gene expression signatures in 46 TN patients and compared the results to those with known driver mutations and healthy volunteers. Deep, error-corrected, next-generation sequencing of peripheral blood mononuclear cells using the HaloPlexHS platform and whole-exome sequencing was performed. Using this platform, 10 (22%) of 46 patients had detectable mutations (MPL, n = 6; JAK2V617F, n = 4) with 3 of 10 cases harboring germline MPL mutations. RNA-sequencing and DNA methylation analysis were also performed by using peripheral blood mononuclear cells. Pathway analysis comparing healthy volunteers and ET patients (regardless of mutational status) identified significant enrichment for genes in the tumor necrosis factor, NFκB, and MAPK pathways and upregulation of platelet proliferative drivers such as ITGA2B and ITGB3. Correlation with DNA methylation showed a consistent pattern of hypomethylation at upregulated gene promoters. Interrogation of these promoter regions highlighted enrichment of transcriptional regulators, which were significantly upregulated in patients with ET regardless of mutation status, including CEBPβ and NFκB. For “true” TN ET, patterns of gene expression and DNA methylation were similar to those in ET patients with known driver mutations. These observations suggest that the resultant ET phenotype may, at least in part and regardless of mutation type, be driven by transcriptional misregulation and may propagate downstream via the MAPK, tumor necrosis factor, and NFκB pathways with resultant JAK-STAT activation. These findings identify potential novel mechanisms of disease initiation that require further evaluation.

Supplemental Digital Content is available in the text., Background: Approximately 25% of patients with pulmonary arterial hypertension (PAH) have been found to harbor rare mutations in disease-causing genes. To identify missing heritability in PAH, we integrated deep phenotyping with whole-genome sequencing data using Bayesian statistics. Methods: We analyzed 13 037 participants enrolled in the NBR study (NIHR BioResource—Rare Diseases), of which 1148 were recruited to the PAH domain. To test for genetic associations between genes and selected phenotypes of pulmonary hypertension, we used the Bayesian rare variant association method BeviMed. Results: Heterozygous, high impact, likely loss-of-function variants in the kinase insert domain receptor (KDR) gene were strongly associated with significantly reduced transfer coefficient for carbon monoxide (posterior probability=0.989) and older age at diagnosis (posterior probability=0.912). We also provide evidence for familial segregation of a rare nonsense KDR variant with these phenotypes. On computed tomographic imaging of the lungs, a range of parenchymal abnormalities were observed in the 5 patients harboring these predicted deleterious variants in KDR. Four additional PAH cases with rare likely loss-of-function variants in KDR were independently identified in the US PAH Biobank cohort with similar phenotypic characteristics. Conclusions: The Bayesian inference approach allowed us to independently validate KDR, which encodes for the VEGFR2 (vascular endothelial growth factor receptor 2), as a novel PAH candidate gene. Furthermore, this approach specifically associated high impact likely loss-of-function variants in the genetically constrained gene with distinct phenotypes. These findings provide evidence for KDR being a clinically actionable PAH gene and further support the central role of the vascular endothelium in the pathobiology of PAH.

Macromolecular crowding and the presence of surfaces can significantly impact the spatial organization of biopolymers. While the importance of crowding-induced depletion interactions in biology has been recognized, much remains to be understood about the effect of crowding on biopolymers such as DNA plasmids. A fundamental problem highlighted by recent experiments is to characterize the impact of crowding on polymer-polymer and polymer-surface interactions. Motivated by the need for quantitative insight, we studied flexible ring polymers in crowded environments using Langevin dynamics simulations. The simulations demonstrated that crowding can lead to compaction of isolated ring polymers and enhanced interactions between two otherwise repulsive polymers. Using umbrella sampling, we determined the potential of mean force (PMF) between two ring polymers as a function of their separation distance at different volume fractions of crowding particles, φ. An effective attraction emerged at φ≈ 0.4, which is similar to the degree of crowding in cells. Analogous simulations showed that crowding can lead to strong adsorption of a ring polymer to a wall, with an effective attraction to the wall emerging at a smaller volume fraction of crowders (φ≈ 0.2). Our results reveal the magnitude of depletion interactions in a biologically-inspired model and highlight how crowding can be used to tune interactions in both cellular and cell-free systems.

INTRODUCTION Explicit motor sequence learning is impaired in Parkinson's disease (PD). Transcranial direct current stimulation (tDCS) applied over the motor cortex in healthy can improve explicit motor learning, but comparative effects in PD are unknown. This exploratory study aims to examine the effect of single session tDCS on explicit motor sequence learning in PD. METHODS Thirty-three people with mild to moderate PD learnt a short and long finger tapping sequence with their right hand. Participants received either anodal, cathodal, or sham tDCS applied over the left primary motor cortex during task practice. Single- and dual-task finger tapping performance was assessed before and after task practice and functional near-infrared spectroscopy used to measure task related changes of oxygenated haemoglobin. RESULTS Finger tapping performance of short and long sequences under single-task conditions significantly improved following practice (p = 0.010 and p

Among many mixed ionic electronic conductors (MIECs), lanthanum strontium cobalt iron oxide (LSCF) has been proven as a promising material for use as cathode in SOFCs. The ion and electron conduction in LSCF need to be studied separately. To measure the ionic conductivity of LSCF, YSZ disks were applied to block the electronic current, and multilayered samples were made with YSZ disks in series with an LSCF disk. Both AC and DC techniques were used for the measurements. An LSCF(porous)/LSCF(dense)/LSCF(porous) bar-shaped sample was made to measure the electronic conductivity of LSCF. DC technique was utilized for the measurement. Results show that the ionic conductivity of LSCF is much lower than its electronic conductivity. The ionic conductivity of LSCF increases with increasing temperature (600 °C–900 °C), and the electronic conductivity decreases with increasing temperature (600 °C–900 °C). Measurements were also made on a foil of silver to investigate oxygen transport through it. From this, oxygen ion conductivity through silver was estimated.

Sterol-C4-methyl oxidase (SC4MOL) deficiency was recently described as an autosomal recessive cholesterol biosynthesis disorder caused by mutations in the MSMO1 (sometimes also referred to as SC4MOL) gene. To date, 5 patients from 4 unrelated families with SC4MOL deficiency have been reported. Diagnosis can be challenging as the biochemical accumulation of methylsterols can affect global development and cause skin and ocular pathology. Herein, we describe 2 siblings from a consanguineous Turkish family with SC4MOL deficiency presenting with psoriasiform dermatitis, ocular abnormalities (nystagmus, optic hypoplasia, myopia, and strabismus), severe intellectual disability, and growth and motor delay. We undertook whole-exome sequencing and identified a new homozygous missense mutation c.81AC; p.Asn27Thr in MSMO1. Segregation analysis in all available family members confirmed recessive inheritance of the mutation. The siblings were treated with a combination of oral and topical statin and cholesterol which resulted in clinical improvement. This study demonstrates how genomics-based diagnosis and therapy can be helpful in clinical practice.

There are several technical challenges to obtaining high-quality recordings of cochlear potentials in human electrocochleography (ECochG). These challenges include electrical artifacts from devices such as acoustic transducers, biological artifacts from excessive myogenic and electroencephalographic potentials, and issues associated with the placement of a tympanic membrane (TM) electrode on the eardrum. This article presents approaches for dealing with these challenges for ECochG measurement using a TM electrode. Emphasis is placed on eliminating stimulus artifact, optimizing the placement of the electrode, and comparing a custom-made electrode with a commercially-available electrode. This comparison revealed that the custom-made electrode results in greater subject comfort, superior ease of placing the electrode on the eardrum, and larger compound action potential (CAP) amplitudes.

Current estimates suggest 50% of glaucoma blindness worldwide is caused by primary angle-closure glaucoma (PACG) but the causative gene is not known. We used genetic linkage and whole genome sequencing to identify Spermatogenesis Associated Protein 13, SPATA13 (NM_001166271; NP_001159743, SPATA13 isoform I), also known as ASEF2 (Adenomatous polyposis coli-stimulated guanine nucleotide exchange factor 2), as the causal gene for PACG in a large seven-generation white British family showing variable expression and incomplete penetrance. The 9 bp deletion, c.1432_1440del; p.478_480del was present in all affected individuals with angle-closure disease. We show ubiquitous expression of this transcript in cell lines derived from human tissues and in iris, retina, retinal pigment and ciliary epithelia, cornea and lens. We also identified eight additional mutations in SPATA13 in a cohort of 189 unrelated PACS/PAC/PACG samples. This gene encodes a 1277 residue protein which localises to the nucleus with partial co-localisation with nuclear speckles. In cells undergoing mitosis SPATA13 isoform I becomes part of the kinetochore complex co-localising with two kinetochore markers, polo like kinase 1 (PLK-1) and centrosome-associated protein E (CENP-E). The 9 bp deletion reported in this study increases the RAC1-dependent guanine nucleotide exchange factors (GEF) activity. The increase in GEF activity was also observed in three other variants identified in this study. Taken together, our data suggest that SPATA13 is involved in the regulation of mitosis and the mutations dysregulate GEF activity affecting homeostasis in tissues where it is highly expressed, influencing PACG pathogenesis., Author summary Glaucoma is the leading cause of irreversible blindness globally. Angle closure glaucoma accounts for 50% of all glaucoma blindness impacting quality of life and burden on health services. A number of variations in DNA appear to influence the risk of the disease. However, the biological mechanism underlying this important disease remains unclear. In this paper, we report the identification and functional characterisation of the first gene, mutation in which causes primary angle closure glaucoma in a seven generation Caucasian family. We have identified other variants in the same gene in another family and individuals with the disease. This gene is involved in cell division and is highly expressed in parts of the eye affected by the disease. Mutations in this gene appear to affect important enzyme activity involved in cell division. Identification of the disease-causing role of mutations in this gene helps to further the understanding of glaucoma aetiology and identifies potential therapeutic targets for disease management.

Dermatofibromas are common benign skin lesions, the etiology of which is poorly understood. We identified two unrelated pedigrees in which there was autosomal dominant transmission of multiple dermatofibromas. Whole exome sequencing revealed a rare shared heterozygous missense variant in the F13A1 gene encoding factor XIII subunit A (FXIII-A), a transglutaminase involved in hemostasis, wound healing, tumor growth, and apoptosis. The variant (p.Lys679Met) has an allele frequency of 0.0002 and is predicted to be a damaging mutation. Recombinant human Lys679Met FXIII-A demonstrated reduced fibrin crosslinking activity in vitro. Of note, the treatment of fibroblasts with media containing Lys679Met FXIII-A led to enhanced adhesion, proliferation, and type I collagen synthesis. Immunostaining revealed co-localization between FXIII-A and α4β1 integrins, more prominently for Lys679Met FXIII-A than the wild type. In addition, both the α4β1 inhibitors and the mutation of the FXIII-A Isoleucine-Leucine-Aspartate-Threonine (ILDT) motif prevented Lys679Met FXIII-A-dependent proliferation and collagen synthesis of fibroblasts. Our data suggest that the Lys679Met mutation may lead to a conformational change in the FXIII-A protein that enhances α4-integrin binding and provides insight into an unexpected role for FXIII-A in the pathobiology of familial dermatofibroma.

PURPOSE To report normative angle alpha orientation and magnitude distribution in a cataract surgery patient population. SETTING U.S. academic medical center. DESIGN Retrospective review. METHODS A total of 11 871 wavefront aberrometer/corneal topographer angle alpha measurements were performed over 40 months, yielding 8773 bilateral measurements (73.9%) with zero bad wavefront datapoints. The analysis was limited to the first right-eye scan for 3382 unique patients. The angle alpha magnitudes (millimeters) and orientations (degrees) were analyzed for these unique right eyes. RESULTS For the 3,382 unique patients, the mean angle alpha magnitude was 0.44 ± 0.15 mm (median, 0.44 mm; 25th and 75th percentiles 0.34 mm, 0.53 mm). Angle alpha orientation was predominantly horizontal (P < .01), with a mean of 186 ± 32 degrees. The expected point of intraocular lens (IOL) centration (EPIC) based on the geometric center of the corneal limbus was temporal to the visual axis in 3212 eyes (95%), nasal in 92 eyes (2.7%), inferior in 56 eyes (1.7%), and superior in 22 eyes (0.6%). The mean angle alpha magnitude was 0.3 mm or less in 607 eyes (18%) and 0.5 mm or greater in 1089 eyes (32%). CONCLUSIONS Angle alpha is a predominantly horizontal phenomenon with a mean EPIC of 0.44 mm temporal to the visual axis. This information may assist in determining eligibility for patients in multifocal IOL implantation.

Motivated by applications such as question answering, fact checking, and data integration, there is significant interest in constructing knowledge graphs by extracting information from unstructured information sources, particularly text documents. Knowledge graphs have emerged as a standard for structured knowledge representation, whereby entities and their inter-relations are represented and conveniently stored as (subject,predicate,object) triples in a graph that can be used to power various downstream applications. The proliferation of financial news sources reporting on companies, markets, currencies, and stocks presents an opportunity for extracting valuable knowledge about this crucial domain. In this paper, we focus on constructing a knowledge graph automatically by information extraction from a large corpus of financial news articles. For that purpose, we develop a high precision knowledge extraction pipeline tailored for the financial domain. This pipeline combines multiple information extraction techniques with a financial dictionary that we built, all working together to produce over 342,000 compact extractions from over 288,000 financial news articles, with a precision of 78% at the top-100 extractions.The extracted triples are stored in a knowledge graph making them readily available for use in downstream applications.

Contains fulltext : 229571.pdf (Publisher’s version ) (Closed access) BACKGROUND: An increasing number of NFKB1 variants are being identified in patients with heterogeneous immunologic phenotypes. OBJECTIVE: To characterize the clinical and cellular phenotype as well as the management of patients with heterozygous NFKB1 mutations. METHODS: In a worldwide collaborative effort, we evaluated 231 individuals harboring 105 distinct heterozygous NFKB1 variants. To provide evidence for pathogenicity, each variant was assessed in silico; in addition, 32 variants were assessed by functional in vitro testing of nuclear factor of kappa light polypeptide gene enhancer in B cells (NF-κB) signaling. RESULTS: We classified 56 of the 105 distinct NFKB1 variants in 157 individuals from 68 unrelated families as pathogenic. Incomplete clinical penetrance (70%) and age-dependent severity of NFKB1-related phenotypes were observed. The phenotype included hypogammaglobulinemia (88.9%), reduced switched memory B cells (60.3%), and respiratory (83%) and gastrointestinal (28.6%) infections, thus characterizing the disorder as primary immunodeficiency. However, the high frequency of autoimmunity (57.4%), lymphoproliferation (52.4%), noninfectious enteropathy (23.1%), opportunistic infections (15.7%), autoinflammation (29.6%), and malignancy (16.8%) identified NF-κB1-related disease as an inborn error of immunity with immune dysregulation, rather than a mere primary immunodeficiency. Current treatment includes immunoglobulin replacement and immunosuppressive agents. CONCLUSIONS: We present a comprehensive clinical overview of the NF-κB1-related phenotype, which includes immunodeficiency, autoimmunity, autoinflammation, and cancer. Because of its multisystem involvement, clinicians from each and every medical discipline need to be made aware of this autosomal-dominant disease. Hematopoietic stem cell transplantation and NF-κB1 pathway-targeted therapeutic strategies should be considered in the future.

Peripheral dark shadows seen by some intraocular lens patients have led to evaluations of “far peripheral vision”. Angular scaling to the second nodal point has been found to be highly linear for the chief ray.

MapReduce is a widely used parallel computing paradigm for the big data realm on the scale of terabytes and higher. The introduction of minimal MapReduce algorithms promised efficiency in load balancing among participating machines by ensuring that partition skew (where some machines end up processing a significantly larger fraction of the input than other machines) is prevented. Despite minimal MapReduce algorithms guarantee of load-balancing within constant multiplicative factors, the constants are relatively large which severely diminishes the theoretical appeal for true efficiency at scale.

Patients awaiting lung transplantation face high wait-list mortality, as injury precludes the use of most donor lungs. Although ex vivo lung perfusion (EVLP) is able to recover marginal quality donor lungs, extension of normothermic support beyond 6 h has been challenging. Here we demonstrate that acutely injured human lungs declined for transplantation, including a lung that failed to recover on EVLP, can be recovered by cross-circulation of whole blood between explanted human lungs and a Yorkshire swine. This xenogeneic platform provided explanted human lungs a supportive, physiologic milieu and systemic regulation that resulted in functional and histological recovery after 24 h of normothermic support. Our findings suggest that cross-circulation can serve as a complementary approach to clinical EVLP to recover injured donor lungs that could not otherwise be utilized for transplantation, as well as a translational research platform for immunomodulation and advanced organ bioengineering.

The alpha emission spectrum of electrodeposited thin film 232Th and depleted uranium sources, including the alpha emitting 232Th decay chain daughters and 238U daughter nuclide 234U, have been measured using a thin film 4H–SiC alpha detector. The energy resolution of this detector was proved suitable for the identification of many of the major characteristic alpha emissions associated with the 232Th daughter isotopes. The identification of the lower energy daughter isotopes made from the 4H–SiC detector measurements was confirmed using a silicon surface barrier detector. A depleted uranium source was fabricated using electrodeposition in a molten salt and the alpha spectrum was acquired with a 4H–SiC detector. The 234U/238U activity ratio and atomic enrichment of 234U in the sample were determined. A method of determining the 235U enrichment in the product stream of the enrichment process used to produce the depleted uranium source was developed. This method makes use of the 234U and 235U waste stream enrichments, as indicated by the depleted uranium source, and a mass balance equation to determine the product 235U enrichment. Since the 235U spectrum was obscured in the electrodeposited source by peak broadening of 238U and 234U, a table of common 235U waste enrichment values was used to compute 235U product enrichments, thereby resulting in a plausible identification of the enrichment process as a Department of Energy HEU enrichment process.

Improvements in the galvanic reduction of UCl 3 from LiCl-KCl- UCl 3 molten salts are reported. This process has potential application for drawdown operations for electrorefiner salt. Short circuiting a gadolinium rod to a stainless steel basket causes a galvanic reaction which results in simultaneous reduction of UCl 3 to U(0) and oxidation of Gd(0) to GdCl 3 . Two galvanic cell configurations were tested: one with the gadolinium metal inserted into the stainless steel basket, and one with the gadolinium metal separated from the stainless steel basket. When using a rotating basket and a physically separated gadolinium metal rod, concentration of uranium decreased from 0.168 to 0.00004 mol % within 105 min, representing over 99.97% removal from salt. Electrochemical potential measurements were recorded for the galvanic couple, and it was found that the potential became more negative during reduction process and leveled off when all of the UCl 3 was reduced. In experiments in which MgCl 2 was added to the salt as a surrogate for PuCl 3 , it was observed to co-deposit with the UCl 3 . Other rare earth chlorides ( LaCl 3 , NdCl 3 , and CeCl 3 ) were not removed from the salt during the reduction process.

Objectives: To identify the genetic basis of severe tooth agenesis in a family of three affected sisters. Patients and Methods: A family of three sisters with severe tooth agenesis was recruited for whole-exome sequencing to identify potential genetic variation responsible for this penetrant phenotype. The unaffected father was tested for specific mutations using Sanger sequencing. Gene discovery was supplemented with in situ hybridization to localize gene expression during human tooth development. Results: We report a nonsense heterozygous mutation in exon 2 of WNT10A c.321C>A[p.Cys107*] likely to be responsible for the severe tooth agenesis identified in this family through the creation of a premature stop codon, resulting in truncation of the amino acid sequence and therefore loss of protein function. In situ hybridization showed expression of WNT10A in odontogenic epithelium during the early and late stages of human primary tooth development. Conclusions: WNT10A has previously been associated with both syndromic and non-syndromic forms of tooth agenesis, and this report further expands our knowledge of genetic variation underlying non-syndromic forms of this condition. We also demonstrate expression of WNT10A in the epithelial compartment of human tooth germs during development.

Recent superresolution microscopy studies in E. coli demonstrate that the cytoplasm has highly variable local concentrations where macromolecular crowding plays a central role in establishing membrane-less compartmentalization. This spatial inhomogeneity significantly influences molecular transport and association processes central to gene expression. Yet, little is known about how macromolecular crowding influences gene expression bursting-the episodic process where mRNA and proteins are produced in bursts. Here, we simultaneously measured mRNA and protein reporters in cell-free systems, showing that macromolecular crowding decoupled the well-known relationship between fluctuations in the protein population (noise) and mRNA population statistics. Crowded environments led to a 10-fold increase in protein noise even though there were only modest changes in the mRNA population and fluctuations. Instead, cell-like macromolecular crowding created an inhomogeneous spatial distribution of mRNA ("spatial noise") that led to large variability in the protein production burst size. As a result, the mRNA spatial noise created large temporal fluctuations in the protein population. These results highlight the interplay between macromolecular crowding, spatial inhomogeneities, and the resulting dynamics of gene expression, and provide insights into using these organizational principles in both cell-based and cell-free synthetic biology.

Background: Sudden infant death syndrome (SIDS) is a leading cause of postneonatal mortality. Genetic heart diseases (GHDs) underlie some cases of SIDS. Objectives: This study aimed to determine the spectrum and prevalence of GHD-associated mutations as a potential monogenic basis for SIDS. Methods: A cohort of 419 unrelated SIDS cases (257 male; average age 2.7 ± 1.9 months) underwent whole exome sequencing and a targeted analysis of 90 GHD-susceptibility genes. The yield of “potentially informative,” ultra-rare variants (minor allele frequency

In this paper, the thermodynamic activity of two lanthanide chlorides (CeCl3 and NdCl3) in molten LiCl-KCl eutectic salt measured using open circuit potentiometry has been reported. Activity coefficient of CeCl3 was found to be strongly dependent on the concentration of CeCl3 in a concentration window of up to 4.66 mol % CeCl3. The activity coefficient of NdCl3 could not be measured due to the uncertainty in NdCl3/NdCl2 molar ratio in the salt, however the thermodynamic activity was measured relative to a 5 mol% Ag∣AgCl reference electrode. The concurrent analysis of data presented in this paper along with previously published activity data for LaCl3 and GdCl3 demonstrates that the departure from ideal solution behavior shown by the rare earths chlorides correlates with ionic size of underlying rare earth element. The smaller the ionic size of the species under consideration, the greater its departure from ideal solution behavior. Further, using the activity data of all four rare earth chlorides, an ionic size dependent correlation was developed. Using this empirical correlation, it is possible to calculate the activity of all species from La(Z = 57) to Gd (Z = 64) for a concentration of up to 2.5 mol% rare earth chloride in LiCl-KCl molten salt at 773 K.

In this paper, results from comprehensive thermoeconomic assessments of small-scale solar organic Rankine cycle (ORC) systems are presented based on weather data in London, UK, which is taken as representative of a temperate climate with modest temperature changes, mild winters and moderate summers. The assessments consider a range of: (i) solar collector types (flat-plate, evacuated-tube, and evacuated flat-plate collectors); (ii) power cycle configurations (basic/recuperative, partial/full evaporating, and subcritical/transcritical cycles); (iii) expander types (scroll, screw, and piston) and designs; and (iv) a set of suitable working fluids. All possible solar-ORC system designs are optimised by considering simultaneously key parameters in the solar field and in the power cycle in order to obtain the highest electricity generation, from which the best-performing systems are identified. Selected designs are then subjected to detailed, annual simulations considering the systems’ operation, explicitly considering off-design performance under actual varying weather conditions. The results indicate that, among all investigated designs, solar-ORC systems based on the subcritical recuperative ORC (SRORC), evacuated flat-plate collectors (EFPCs), a piston expander, and isobutane as the working fluid outperforms all the other system designs on thermodynamic performance, whilst having the highest annual electricity generation of 1,100 kW·h/year (73 kW·h/year/m2) and an overall thermal efficiency of 5.5%. This system also leads to the best economic performance with a levelised cost of energy (LCOE) of ~1 $/kW·h. Apart from the specific weather data used for these detailed system simulations, this study also proceeds to consider a wider range of climates associated with other global regions by varying the solar resource available to the system. Interestingly, it is found that the optimal solar-ORC system design remains unchanged for different conditions, however, the LCOE can drop below 0.35 $/kW·h and payback times can be shorter than 16 years in high solar-resource regions, even in the absence of incentives that would otherwise lead to even better economic performance. This work complements previous efforts in the literature by considering the full design and operational features of solar-ORC systems, thereby providing valuable guidance for selecting appropriate cycle configurations, components, working fluids and other characteristics and, for the first time, presents a comprehensive comparison of such systems in small-scale applications.

The mathematical modelling and optimization of a gas-to-gas heat exchanger with a non-constant cross sectional area is presented. The design of the cross sectional area of the heat exchanger analyzed is based on an hexagonal mesh, which would be highly impractical to fabricate in a conventional way but could be built relatively easily through modern manufacturing techniques. The geometric configuration proposed allows attaining a high exergy efficiency and a significant cost reduction, measured in terms of volume per unit of exergy transfer. The relationship that exists between the overall exergy efficiency of the heat exchanger and its cost is thoroughly explained throughout the study. The results obtained from the modelling demonstrate the premise that it is possible to realize designs for heat exchangers that are highly exergy-efficient and very cheap, owing to the small volume of material required, if the constrains imposed by the limitations of traditional manufacturing methods are set aside. Furthermore, the study reveals a very important fact: the volume of material in a heat exchanger increases in quadratic proportion to its characteristic dimension, which implies that scaling up the geometry has a strong impact on its cost-effectiveness.

During normal operations, the only deposition on a spent nuclear fuel electrorefiner cathode consists of uranium. A computer model, ERAD, was used to simulate conditions under which the electrorefiner salt was progressively contaminated from spent nuclear fuel processing without operator intervention. The model was adjusted to reflect three scenarios: one in which salt removed with every cathode deposit was returned but the UCl 3 concentration was never adjusted, one in which the salt was not removed and UCl 3 concentration was never adjusted, and one in which the Pu/U ratio in the salt was allowed to reach a value of one before starting the first scenario. Under the base conditions simulated, uranium initially deposits alone but eventually plutonium begins to co-deposit along with uranium. Up to 350 g of plutonium was calculated to deposit along with 8.3–9.5 kg of uranium. While precise tracking of changes in the salt composition may not be possible, the model was able to identify markers for plutonium deposition by tracking changes in electrode potential. This type of marker should ultimately provide inspectors with more options for situations when they have limited access to electrorefiner data.

In recent years several proposals for thermodynamic cycles involving the compression and expansion of gas and thermal storage have been put forward as effective ways of storing energy. These include the work of Desrues [1] who proposed a thermal energy storage process for large scale electric applications, Isentropic Ltd [2] who were working on a pumped thermal energy storage system and Garvey who proposed storing wind energy using a wind driven thermal pumping system known as Wind-TP [3]. All these systems require a hot and a cold store capable of storing thermal energy which can later be used to generate electricity. The efficiency and ultimately the successful adoption of pumped thermal energy storage will depend on the effectiveness of the thermal stores. In this paper we compare the performance of a packed bed and a liquid thermocline as the cold store for an off-shore Wind-TP system. Simulations are used to compare the exergetic performance of the two options leading to the conclusion that a liquid thermocline has potential to be significantly more effective than a packed bed thermocline. An addition to a liquid store involving a sliding divider separating warm and cold fluid is proposed as a way of avoiding exergy losses associated with the smearing of a thermocline front.

PREMISE OF THE STUDY American amphitropical disjunction (AAD) is an important but understudied New World biogeographic pattern in which related plants occur in extratropical North America and South America, but are absent in the intervening tropics. Subtribe Amsinckiinae (Boraginaceae) is one of the richest groups of plants displaying the AAD pattern. Here, we infer a time-calibrated molecular phylogeny of the group to evaluate the number, timing, and directionality of AAD events, which yields generalizable insights into the mechanism of AAD. METHODS We perform a phylogenomic analysis of 139 samples of subtribe Amsinckiinae and infer divergence times using two calibration schemes: with only fossil calibrations and with fossils plus a secondary calibration from a recent family level analysis. Biogeographic analysis was performed in the R package BioGeoBEARS. KEY RESULTS We document 18 examples of AAD in the Amsinckiinae. Inferred divergence times of these AAD examples were strongly asynchronous, ranging from Miocene (17.1 million years ago [Ma]) to Pleistocene (0.33 Ma), with most (12) occurring

Reversible cells can be used as solid oxide fuel cells (SOFC) and solid oxide electrolyzer cells (SOEC). The solid electrolytes used for such cells frequently have pure ionic conduction with insignificant electronic conduction. A previous study (Virkar and Tao, 2015) has shown that cells made of ceria doped yttrium stabilized zirconia (YSZ), a mixed ionic electronic conducting (MIEC) material, can be made to operate at the same efficiency level and with superior stability compared to a pure ionic conductor, like pure YSZ. This work is a continuation of that study, examining the use of gadolinium doped ceria (GDC) mixed with YSZ. The MIEC cell, 8mol%GDC+YSZ, will be further tested and designed to consume fuel or water vapor, generate power or hydrogen, and release heat at the same rate as the pure ionic conducting cell, YSZ, when operating in SOFC or SOEC mode. Future testing will also determine if the GDC MIEC cell can match or exceed the durability of the ceria doped YSZ. The electrolyte layer, made of either pure 8YSZ or 8YSZ doped with 8mol%GDC, was die pressed and sintered at 1400oC (2oC/min) for five hours. On one side of the electrolyte, the anode interlayer is mixed with isopropyl alcohol and painted on the electrolyte's surface. The anode interlayer is composed of 50wt% NiO and 50wt% 8YSZ. The cell was heated to 950oC (2oC/min) for one hour. The anode functional layer, 70wt% NiO and 30wt% 8YSZ, was painted on top of the anode interlayer. The sample was then again heated to 950oC (2oC/min) for one hour to burn off any organic compounds. A cathode interlayer was then painted on the other side of the electrolyte layer. The cathode interlayer was also painted on and consists of 50wt% lanthanum strontium manganite (LSM) and 50wt% YSZ. The cell is heated to 1200oC (2oC/min) for two hours. Finally, a pure LSM layer is painted on top as the cathode current collector material and heated to 1100oC (2oC/min) for one hour to ensure good porosity. The cells were then sealed by compression-loading at the edges using glass-mica seals. Results of tests will be reported for both SOEC and SOFC modes at 800oC. Data to be reported include open-circuit voltage, area-specific resistance, corresponding ionic currents based on an applied voltage, and long-term durability of the two cells in both SOFC and SOEC modes.