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MAST-Upgrade (MAST-U) is undergoing several enhancements to deliver increased performance and functionality. One such enhancement is the design, development, and implementation of an electron Bernstein wave (EBW) heating and current drive (HCD) system. The MAST-U EBW System aims to provide experimental data for model validation, along with a greater understanding of EBW physics and its capabilities. The MAST-U EBW System will deliver up to $\mathbf {1.8}$ MW of microwave power via two microwave beams, at the dual frequencies of 28 and 34.8 GHz for up to $\mathbf {4.5}$ s. This article provides an update on the system’s in-vessel components, with particular focus on the quasi-optical launcher design and modeled performance.

Many mark–recapture models assume that releases and recaptures are discrete events, and researchers often aggregate continuous recapture data (e.g., passive integrated transponder [PIT] detections) into coarse temporal scales to satisfy this assumption. This temporal discretization could result in parameter biases by ignoring the individual heterogeneity in the time susceptible to mortality after recapture and the conditions experienced (e.g., temperature and predation risk) before and after recapture. Our objectives were to (1) estimate the amount of bias in survival and emigration rates due to different temporal discretization durations when recapture events occur continuously and (2) apply this semicontinuous model to estimate rates of early emigration and overwinter survival for Coho Salmon Oncorhynchus kisutchin a coastal California watershed. We developed a semicontinuous time multistate mark–recapture model to separately estimated emigration and survival rates throughout the year. We used weekly time‐varying occasions paired with discrete spatial states and conducted extensive simulation trials to explore potential model bias. We then applied the model to an existing 4‐year dataset of Coho Salmon PIT tag detections. Our simulations indicated that that the amount of bias in survival and movement rates decreased as the temporal discretization duration decreased. The confidence interval of the bias estimates included zero with a duration of 8 days, indicating that this duration was sufficiently short to model movement and survival. Results from our Coho Salmon analysis suggest that overwinter survival rate ranged from 0.72 to 0.83, which is higher than previous estimates for Coho Salmon in this region. We estimate that a substantial proportion of smaller juveniles (0.21–0.28 annually) move to downstream nonnatal rearing habitats before the spring smolt migration. Our semicontinuous modeling approach can be implemented relatively easily and used to analyze continuous detection data to accurately estimate survival and movement rates. Our analysis of Coho Salmon PIT tag detections implies that previous low estimates of apparent overwinter survival of Coho Salmon were partially due to high movement rates to alternative rearing locations. This contrasts with conclusions from the previous research that suggested that overwinter survival was a major limiting factor for population recovery and implies that species recovery may be improved by considering multiple emigration patterns in the design of future research, monitoring, and restoration projects. Impact statementGrouping continuous mark–recapture data into single recapture events (e.g., monthly or seasonal) can bias estimates of survival and movement rates from mark–recapture models. Grouping continuous mark–recapture data into single recapture events (e.g., monthly or seasonal) can bias estimates of survival and movement rates from mark–recapture models.

The microstructure of a compressed explosive solid is closely related to its shock sensitivity and mechanical properties. In this study, ultra-small-angle and small-angle X-ray scattering (USAXS and SAXS) techniques were combined to explore the hierarchical microstructure of die-pressed 2,4,6-trinitro-1,3,5-benzenetriamine (TATB) discs obtained from nanostructured TATB (nano-TATB) powder as the precursor. Using the Guinier-Porod model, the pseudo-invariants, and Porod's law, this study analyzed the microstructures of the materials on a nanometer scale to track the changes in void size, porosity, and interfacial area, which reflected the response of TATB under applied pressures of 1, 2, 5, 10, 15 ​kN and 30 ​kN. Results show that there existed three populations of voids in the measured qrange. The intergranular voids with sizes of tens of nanometers were sensitive to low pressures (<15 ​kN) and presented a smooth interface with the TATB matrix. The intragranular voids with sizes of 7–8 ​nm exhibited a fairly small volume-filling ratio under high pressures (>15 ​kN), as indicated by the decrease in the volume fractal dimension. Porosities of the voids with sizes of 1–900 ​nm, which were determined by the pseudo-invariants obtained from the scattering data, decreased from 6% to 1% as the pressures increased from 1 ​kN to 30 ​kN. The response of these structural parameters to external pressures implies that the main densification mechanisms under die compression include the flow, fracturing, and plastic deformation of the TATB granules. This study provides a direct insight into the structural evolution of TATB during compression.

The Sacramento–San Joaquin Delta (hereafter, “the Delta”) is one of the estuaries with the most invasive species in the world, and nonnative predators may be a major factor in the observed decline of Central Valley Chinook Salmon Oncorhynchus tshawytschaover recent decades. In order for managers to take actions that might reduce predation‐related mortality for these ecologically, culturally, and economically valuable fish, it is important to understand the factors influencing the distribution and abundance of piscivores in the Delta. In this study, we used a dual‐frequency identification sonar (i.e., DIDSON) to conduct mobile surveys to quantify the abundances of piscivores in the Delta. We then used these data to identify the habitat features that are correlated with the abundance of piscivores. Prior to conducting the surveys, we used DIDSON data from captured fish to develop an algorithm to distinguish piscivores from nonpiscivores with high confidence (98% accuracy). A generalized linear mixed‐effects model fit to these survey data indicated that predator abundances were most associated with areas of increased submerged aquatic vegetation patches, and channels that are straighter, with increased bathymetric complexity. When applied to the entire survey area, this model was successfully able to predict known areas of high predator densities. These results indicate that one approach to reduce predator densities in key locations throughout the Delta, and improve juvenile salmonid outmigration survival, is to reduce the extent of invasive submerged aquatic vegetation. Because experimental predator removals have been largely ineffective in the Delta, efforts to manipulate habitat to discourage nonnative predator recruitment and favor native species recruitment may provide a more effective solution to improve salmonid survival rates.

Analysis of artifacts collected by the late Helen G. Blumenschein (HGB) provides a region-wide database for obsidian use between the Middle – Late Archaic and the Talpa phase in the Taos area of northern New Mexico, approximately 3000 B.C.E. to 1300 C.E. Using GIS to associate these artifacts with site locations from HGB’s records and the current site files maintained by the State of New Mexico allows us to verify locations of HGB’s work and to associate these artifacts with documented archaeological sites. However, many of HGB’s collection localities are not presently recorded in official site records, meaning that a significant amount of data can still be recovered from these 50+ year old documents. Results of our obsidian sourcing suggest that El Rechuelos obsidian accounts for nearly two-thirds of obsidian use between the Archaic and the Talpa phase, indicating a consistent lithic-source preference by Taos-area residents over several millennia.

The application of radio frequency (RF) vacuum electronics for the betterment of the human condition began soon after the invention of the first vacuum tubes in the 1920s and has not stopped since. Today, microwave vacuum devices are powering important applications in health treatment, material and biological science, wireless communication—terrestrial and space, Earth environment remote sensing, and the promise of safe, reliable, and inexhaustible energy. This article highlights some of the exciting application frontiers of vacuum electronics.

Background: Cardiopulmonary bypass (CPB) causes systemic inflammation during pediatric cardiac surgery, which can contribute to post-operative organ dysfunction and prolonged recovery. This study aims to identify key inflammatory mediators related to this clinically significant immunologic response. Methods: Pediatric patients were enrolled in a single-arm prospective clinical study (NCT05154864) and received standard cardiac operation, CPB and subzero-balance ultrafiltration. Arterial samples were taken before CPB initiation and immediately after weaning, and concentrations of 33 inflammatory mediators were assayed. A principal component analysis with hierarchical clustering (PCA-HCPC) included inflammatory mediator concentrations measured at the end of CPB, validated peak post-operative clinical scores, ventilation time and intensive care length of stay. Mahalanobis distance assessed statistical differences between clusters. Spearman’s correlation described the linear relationship between mediator concentrations at the end of CPB and intensive care length of stay. Results are median (IQR). Results: Forty consecutive patients were enrolled; the majority were male (58%), age of 7.3 (1.7–39.0) months and weight of 6.7 (4.6–14.9) kg. The PCA-HCPC revealed activated complement factors along with all peak clinical scores and prolonged intensive care requirements in the same cluster. Cytokine, chemokine, and leukocyte adhesion molecule concentrations were found in two other distinct clusters (Mahalanobis distance = 16.5; p= 0.004 and Mahalanobis distance = 17.4; p= 5.8 × 10–4). Mediator concentrations of C2 (Rho = 0.50; p= 0.001), C3 (Rho = 0.58; p= 1.1 × 10–4), C3b (Rho = 0.47; p= 0.002), C5 (Rho = 0.48; p= 0.002) and C5a (Rho = 0.63; 1.7 × 10–5) showed linear correlations with intensive care unit length of stay. Conclusions: Activated complement factors, but not pro-inflammatory cytokines or chemokines, were most related to cardiopulmonary dysfunction and prolonged recovery in this novel analysis. Investigation of therapies that inhibit complement to dampen CPB-associated inflammation and enhance recovery after pediatric cardiac surgery is warranted.

Determining a molecule’s mechanism of action is paramount during chemical probe development and drug discovery. The cellular thermal shift assay (CETSA) is a valuable tool to confirm target engagement in cells for a small molecule that demonstrates a pharmacological effect. CETSA directly detects biophysical interactions between ligands and protein targets, which can alter a protein’s unfolding and aggregation properties in response to thermal challenge. In traditional CETSA experiments, each temperature requires an individual sample, which restricts throughput and requires substantial optimization. To capture the full aggregation profile of a protein from a single sample, we developed a prototype real-time CETSA (RT-CETSA) platform by coupling a real-time PCR instrument with a CCD camera to detect luminescence. A thermally stable Nanoluciferase variant (ThermLuc) was bioengineered to withstand unfolding at temperatures greater than 90 °C and was compatible with monitoring target engagement events when fused to diverse targets. Utilizing well-characterized inhibitors of lactate dehydrogenase alpha, RT-CETSA showed significant correlation with enzymatic, biophysical, and other cell-based assays. A data analysis pipeline was developed to enhance the sensitivity of RT-CETSA to detect on-target binding. RT-CETSA technology advances capabilities of the CETSA method and facilitates the identification of ligand-target engagement in cells, a critical step in assessing the mechanism of action of a small molecule.

The perinucleolar compartment (PNC) is a dynamic subnuclear body found at the periphery of the nucleolus. The PNC is enriched with RNA transcripts and RNA-binding proteins, reflecting different states of genome organization. PNC prevalence positively correlates with cancer progression and metastatic capacity, making it a useful marker for metastatic cancer progression. A high-throughput, high-content assay was developed to identify novel small molecules that selectively reduce PNC prevalence in cancer cells. We identified and further optimized a pyrrolopyrimidine series able to reduce PNC prevalence in PC3M cancer cells at submicromolar concentrations without affecting cell viability. Structure–activity relationship exploration of the structural elements necessary for activity resulted in the discovery of several potent compounds. Analysis of in vitrodrug-like properties led to the discovery of the bioavailable analogue, metarrestin, which has shown potent antimetastatic activity with improved survival in rodent models and is currently being evaluated in a first-in-human phase 1 clinical trial.

Patients with valvular heart disease may present with or without symptoms. A thorough cardiac physical examination can identify patients who require further evaluation and management. Although the utility of different cardiac findings varies widely, diastolic murmurs indicate important underlying valvular pathology requiring further investigation, typically with echocardiography. The proper examination of patients with systolic murmurs, the most common murmurs in clinical practice, is fundamental to cost-effective care. We will review the key components of the cardiac examination and findings relevant to functional murmurs, aortic stenosis, mitral valve prolapse and regurgitation, tricuspid regurgitation, hypertrophic cardiomyopathy, aortic regurgitation, and mitral stenosis.

Nontypeable Haemophilus influenzae(NTHi) are clinically important Gram-negative bacteria that are responsible for various human mucosal diseases, including otitis media (OM). Recurrent OM caused by NTHi is common, and infections that recur less than 2 weeks following antimicrobial therapy are largely attributable to the recurrence of the same strain of bacteria. Toxin–antitoxin (TA) modules encoded by bacteria enable rapid responses to environmental stresses and are thought to facilitate growth arrest, persistence, and tolerance to antibiotics. The vapBC-1locus of NTHi encodes a type II TA system, comprising the ribonuclease toxin VapC1 and its cognate antitoxin VapB1. The activity of VapC1 has been linked to the survival of NTHi during antibiotic treatment both in vivoand ex vivo. Therefore, inhibitors of VapC1 might serve as adjuvants to antibiotics, preventing NTHi from entering growth arrest and surviving; however, none have been reported to date. A truncated VapB1 peptide from a crystal structure of the VapBC-1 complex was used to generate pharmacophore queries to facilitate a scaffold hopping approach for the identification of small-molecule VapC1 inhibitors. The National Center for Advancing Translational Sciences small-molecule library was virtually screened using the shape-based method rapid overlay of chemical structures (ROCS), and the top-ranking hits were docked into the VapB1 binding pocket of VapC1. Two hundred virtual screening hits with the best docking scores were selected and tested in a biochemical VapC1 activity assay, which confirmed eight compounds as VapC1 inhibitors. An additional 60 compounds were selected with structural similarities to the confirmed VapC1 inhibitors, of which 20 inhibited VapC1 activity. Intracellular target engagement of five inhibitors was indicated by the destabilization of VapC1 within bacterial cells from a cellular thermal shift assay; however, no impact on bacterial growth was observed. Thus, this virtual screening and scaffold hopping approach enabled the discovery of VapC1 ribonuclease inhibitors that might serve as starting points for preclinical development.

Supplemental Digital Content is available in the text.

A new type of uranium pseudo-colloid was prepared by mixing quasi-monodisperse polystyrene-b-poly(acrylic acid) (PS-b-PAA) micelle dispersions with uranyl carbonate (UC) in order to simulate the structure and transport of colloidal fulvic acids with uranium. A micelle model composed of a homogeneous PS core and a PAA corona was employed to derive the geometrical and contrast parameters of the PS-b-PAA micelles from small-angle X-ray scattering data. The modelled data indicated the multidentate complexation of UC anions to the negatively charged PAA segments, as shown by the shrinkage and the increased density of the PAA corona with increasing UC concentrations. The hydrodynamic size of the micelles decreased from 102 nm to 73 nm with increasing UC concentration, and the zeta potential remained constant at around −40 mV. The prepared pseudo-colloid of uranium has comparable size, zeta potential, and functional groups with those of colloidal fulvic acids. In addition, column experiments indicated that micelle-borne uranium could diffuse easily through quartz sand. This result indicates a potential risk of humic substances to promote the mobility of actinides in a deep geological nuclear waste disposal environment.

Lactate dehydrogenase (LDH) catalyzes the conversion of pyruvate to lactate, with concomitant oxidation of reduced nicotinamide adenine dinucleotide as the final step in the glycolytic pathway. Glycolysis plays an important role in the metabolic plasticity of cancer cells and has long been recognized as a potential therapeutic target. Thus, potent, selective inhibitors of LDH represent an attractive therapeutic approach. However, to date, pharmacological agents have failed to achieve significant target engagement in vivo, possibly because the protein is present in cells at very high concentrations. We report herein a lead optimization campaign focused on a pyrazole-based series of compounds, using structure-based design concepts, coupled with optimization of cellular potency, in vitrodrug–target residence times, and in vivoPK properties, to identify first-in-class inhibitors that demonstrate LDH inhibition in vivo. The lead compounds, named NCATS-SM1440(43) and NCATS-SM1441(52), possess desirable attributes for further studying the effect of in vivoLDH inhibition.

The interactions between natural colloidal organic matter and actinides in solutions are complex and not fully understood. In this work, a crew-cut polystyrene-b-poly(acry1ic acid) (PS-b-PAA) micelle is proposed as a model particle for humic acid (HA) colloid with the aim to better understand the sequestration, aggregation, and mobility of HA colloids in the presence of uranyl ions. The effects of uranyl ions on the structure of PS29k-b-PAA5kmicelles in aqueous solution were mainly investigated by synchrotron small-angle X-ray scattering. A core–shell model, accounting for the thickness and contrast changes of the PAA corona induced by the adsorption of uranyl, was employed to analyze the scattering data. A combination of transmission electron microscopy, dynamic light scattering, and zetametry showed a strong affinity of uranyl ions to PAA segments in water at pH 4–5 that resulted in the shrinkage and improved contrast of the PAA corona, as well as colloidal destabilization at a high uranyl concentration.

A series of quinazolin-4-one based hydroxamic acids was rationally designed and synthesized as novel dual PI3K/HDAC inhibitors by incorporating an HDAC pharmacophore into a PI3K inhibitor (Idelalisib) via an optimized linker. Several of these dual inhibitors were highly potent (IC50< 10 nM) and selective against PI3Kγ, δ and HDAC6 enzymes and exhibited good antiproliferative activity against multiple cancer cell lines. The lead compound 48c, induced necrosis in several mutant and FLT3-resistant AML cell lines and primary blasts from AML patients, while showing no cytotoxicity against normal PBMCs, NIH3T3, and HEK293 cells. Target engagement of PI3Kδ and HDAC6 by 48cwas demonstrated in MV411 cells using the cellular thermal shift assay (CETSA). Compound 48cshowed good pharmacokinetics properties in mice via intraperitoneal (ip) administration and provides a means to examine the biological effects of inhibiting these two important enzymes with a single molecule, either in vitro or in vivo.

Abstract ID 130936

The molecular mechanisms underlying seizure generation remain elusive, yet they are crucial for developing effective treatments for epilepsy. The current study shows that inhibiting c-Abl tyrosine kinase prevents apoptosis, reduces dendritic spine loss, and maintains N-methyl-d-aspartate (NMDA) receptor subunit 2B (NR2B) phosphorylated in in vitromodels of excitotoxicity. Pilocarpine-induced status epilepticus (SE) in mice promotes c-Abl phosphorylation, and disrupting c-Abl activity leads to fewer seizures, increases latency toward SE, and improved animal survival. Currently, clinically used c-Abl inhibitors are non-selective and have poor brain penetration. The allosteric c-Abl inhibitor, neurotinib, used here has favorable potency, selectivity, pharmacokinetics, and vastly improved brain penetration. Neurotinib-administered mice have fewer seizures and improved survival following pilocarpine-SE induction. Our findings reveal c-Abl kinase activation as a key factor in ictogenesis and highlight the impact of its inhibition in preventing the insurgence of epileptic-like seizures in rodents and humans.

There have been many advances in the perfusion equipment used for cardiopulmonary bypass (CPB) surgery. A key component, the membrane oxygenator, has had a number of modifications in recent years and a recent clinical evaluation demonstrated disparity in various aspects of device performance. One difference among oxygenators, which to-date has received little attention, was the impact on the patient’s immune cells, with some oxygenators producing a significantly greater increase in immune cell numbers after cross clamp. Such increases in immune cell proliferation maycontribute to the development of a systemic inflammatory response (SIR), which has been demonstrated to have a negative impact on patient outcomes. Although factors contributing to immune cell proliferation during CPB are recognized to be multi-factorial, the goal of the current communication was to perform an ad hoc analysis of these raw data for evidence that pressure gradients through an oxygenator contributes to this outcome. Despite the observation that higher-pressure gradient oxygenators appeared to associate with increased immune cell proliferation, no correlation was detected in this analysis. This finding, however, provides further evidence for the complex nature of inflammation during CPB, which deserves ongoing discussion and investigation.

Histone deacetylases (HDACs) are epigenetic modulators linked to diseases including cancer and neurodegeneration. Given their therapeutic potential, highly sensitive biochemical and cell-based profiling technologies have been developed to discover small-molecule HDAC inhibitors. Ultimately, the therapeutic action of these inhibitors is dependent on a physical engagement with their intended targets in cellular and tissue environments. Confirming target engagement in the cellular environment is particularly relevant for HDACs since they function as part of cell type-specific multiprotein complexes. Here we implemented two recently developed high-throughput target engagement technologies, NanoBRET and SplitLuc CETSA, to profile 349 compounds in the Epigenetic-Focused collection for HDAC1 binding. We found that the two HDAC1 target engagement assays correlated well with each other and with orthogonal activity-based assays, in particular those carried out in cellular environments rather than with isolated HDAC proteins. The assays detected a majority of the previously described HDAC1 inhibitors in the collection and, importantly, triaged HDAC inhibitors known to target other HDACs.

Histone deacetylases (HDACs) are epigenetic modulators linked to diseases including cancer and neurodegeneration. Given their therapeutic potential, highly sensitive biochemical and cell-based profiling technologies have been developed to discover small-molecule HDAC inhibitors. Ultimately, the therapeutic action of these inhibitors is dependent on a physical engagement with their intended targets in cellular and tissue environments. Confirming target engagement in the cellular environment is particularly relevant for HDACs since they function as part of cell type-specific multiprotein complexes. Here we implemented two recently developed high-throughput target engagement technologies, NanoBRET and SplitLuc CETSA, to profile 349 compounds in the Epigenetic-Focused collection for HDAC1 binding. We found that the two HDAC1 target engagement assays correlated well with each other and with orthogonal activity-based assays, in particular those carried out in cellular environments rather than with isolated HDAC proteins. The assays detected a majority of the previously described HDAC1 inhibitors in the collection and, importantly, triaged HDAC inhibitors known to target other HDACs.

Thermal shift assays (TSAs) can reveal changes in protein structure, due to a resultant change in protein thermal stability. Since proteins are often stabilized upon binding of ligand molecules, these assays can provide a readout for protein target engagement. TSA has traditionally been applied using purified proteins and more recently has been extended to study target engagement in cellular environments with the emergence of cellular thermal shift assays (CETSAs). The utility of CETSA in confirming molecular interaction with targets in a more native context, and the desire to apply this technique more broadly, has fueled the emergence of higher-throughput techniques for CETSA (HT-CETSA). Recent studies have demonstrated that HT-CETSA can be performed in standard 96-, 384-, and 1536-well microtiter plate formats using methods such as beta-galactosidase and NanoLuciferase reporters and AlphaLISA assays. HT-CETSA methods can be used to select and characterize compounds from high-throughput screens and to prioritize compounds in lead optimization by facilitating dose–response experiments. In conjunction with cellular and biochemical activity assays for targets, HT-CETSA can be a valuable addition to the suite of assays available to characterize molecules of interest. Despite the successes in implementing HT-CETSA for a diverse set of targets, caveats and challenges must also be recognized to avoid overinterpretation of results. Here, we review the current landscape of HT-CETSA and discuss the methodologies, practical considerations, challenges, and applications of this approach in research and drug discovery. Additionally, a perspective on potential future directions for the technology is presented.

Thermal shift assays (TSAs) can reveal changes in protein structure, due to a resultant change in protein thermal stability. Since proteins are often stabilized upon binding of ligand molecules, these assays can provide a readout for protein target engagement. TSA has traditionally been applied using purified proteins and more recently has been extended to study target engagement in cellular environments with the emergence of cellular thermal shift assays (CETSAs). The utility of CETSA in confirming molecular interaction with targets in a more native context, and the desire to apply this technique more broadly, has fueled the emergence of higher-throughput techniques for CETSA (HT-CETSA). Recent studies have demonstrated that HT-CETSA can be performed in standard 96-, 384-, and 1536-well microtiter plate formats using methods such as beta-galactosidase and NanoLuciferase reporters and AlphaLISA assays. HT-CETSA methods can be used to select and characterize compounds from high-throughput screens and to prioritize compounds in lead optimization by facilitating dose–response experiments. In conjunction with cellular and biochemical activity assays for targets, HT-CETSA can be a valuable addition to the suite of assays available to characterize molecules of interest. Despite the successes in implementing HT-CETSA for a diverse set of targets, caveats and challenges must also be recognized to avoid overinterpretation of results. Here, we review the current landscape of HT-CETSA and discuss the methodologies, practical considerations, challenges, and applications of this approach in research and drug discovery. Additionally, a perspective on potential future directions for the technology is presented.

The choice of antithrombotic therapy for atrial fibrillation (AF) patients who have an acute coronary syndrome (ACS) or have undergone percutaneous coronary intervention (PCI) is challenging. We aimed to assess outcomes between dual-antithrombotic therapy with the use of direct-acting oral anticoagulants (DOACs) plus an antiplatelet agent (dual therapy) compared with warfarin plus 2 antiplatelet agents (triple therapy) for AF patients after PCI or with ACS.