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The Cloverly Formation of Montana and Wyoming preserves abundant nonmarine vertebrate fossils from the mid-Cretaceous, yet its paleoenvironment and faunal niche structure remain poorly understood. We analyzed δ¹⁸Ο_phosphatein over 100 fossil individuals from multiple vertebrate taxa collected from a single microfossil bonebed in Carbon County, Montana.To infer habitat preferences and water-use strategies, we compared δ¹⁸Ο_phosphatevalues within and across taxa. We reconstructed δ¹⁸O_{surface_water}from semi-aquatic reptile values using regressions calibrated with data from modern environments and extant taxa. Using a multi-taxon framework, we estimated warm-season water temperatures from δ¹⁸O_{surface_water}and δ¹⁸Ο_phosphateof lepisosteid (gar) scales, then converted these to air temperatures using a modern climate transfer function. δ¹⁸Ο_phosphatevalues ranged from 9.5‰ to 23.2‰ (VSMOW) and varied across taxa. Aquatic and semi-aquatic groups exhibited lower values than dinosaurian taxa. Our reconstructed mean δ¹⁸O_{surface_water}was −7.9‰ (95% CI: −10.1 to 5.5‰), yielding a warm-season water temperature of 26°C and an air temperature of 24°C. Intertaxon differences reflect niche partitioning and suggest primary isotopic signals are preserved. Unexpectedly high values in Bernissartiid-like neosuchian teeth may indicate greater ecohydrological diversity than previously recognized. Our δ¹⁸O_{surface_water}estimate aligns with other Aptian-Albian proxies but exceeds model-based predictions, likely due to outdated assumptions underlying the model. The MAWSAT estimate falls within the upper range of model-data assimilation outputs. These results provide new context for ecological structure in the Cloverly fauna and offer the first quantitative temperature estimate for the Formation, helping to define baseline conditions between the Aptian-Albian Cold Snap and the Cretaceous Thermal Maximum. 

Cellular heterogeneity, an inherent feature of biological systems, plays a critical role in processes such as development, immune response, and disease progression. Human mesenchymal stem cells (hMSCs) exemplify this heterogeneity due to their multi-lineage differentiation potential. However, their inherent variability complicates clinical use, and there is no universally accepted method for detecting and quantifying cell population heterogeneity. Dielectrophoresis (DEP) has emerged as a powerful electrokinetic technique for characterizing and manipulating cells based on their dielectric properties, offering label-free analysis capabilities. Quantitative information from the DEP spectrum, such as transient slope, measure cells’ transition between negative and positive DEP behaviors. In this study, we employed DEP to estimate transient slope of various cell populations, including relatively homogeneous HEK-293 cells, heterogeneous hMSCs, and cancer cells (PC3 and DU145). Our analysis encompassed hMSCs derived from bone marrow, adipose, and umbilical cord tissue, to capture tissue-specific heterogeneity. Transient slope was assessed using two methods, involving linear trendline fitting to different low-frequency regions of the DEP spectrum. We found that transient slope serves as a reliable indicator of cell population heterogeneity, with more heterogeneous populations exhibiting lower transient slopes and higher standard deviations. Validation using cell morphology, size, and stemness further supported the utility of transient slope as a heterogeneity metric. This label-free approach holds promise for advancing cell sorting, biomanufacturing, and personalized medicine. 

Abstract Human mesenchymal stem cells (hMSCs) have gained traction in transplantation therapy due to their immunomodulatory, paracrine, immune‐evasive, and multipotent differentiation potential. The inherent heterogeneity of hMSCs poses a challenge for therapeutic treatments and necessitates the identification of robust biomarkers to ensure reproducibility in both in vivo and in vitro experiments. In this study, we utilized dielectrophoresis (DEP), a label‐free electrokinetic phenomenon, to investigate the heterogeneity of hMSCs derived from bone marrow (BM) and adipose tissue (AD). The electrical properties of BM‐hMSCs were compared to homogeneous mouse fibroblasts (NIH‐3T3), human fibroblasts (WS1), and human embryonic kidney cells (HEK‐293). The DEP profile of BM‐hMSCs differed most from HEK‐293 cells. We compared the DEP profiles of BM‐hMSCs and AD‐hMSCs and found that they have similar membrane capacitances, differing cytoplasm conductivity, and transient slopes. Inducing both populations to differentiate into adipocyte and osteoblast cells revealed that they behave differently in response to differentiation‐inducing cytokines. Histology and reverse transcription‐quantitative polymerase chain reaction (RT‐qPCR) analyses of the differentiation‐related genes revealed differences in heterogeneity between BM‐hMSCs and AD‐hMSCs. The differentiation profiles correlate well with the DEP profiles developed and indicate differences in the heterogeneity of BM‐hMSCs and AD‐hMSCs. Our results demonstrate that using DEP, membrane capacitance, cytoplasm conductivity, and transient slope can uniquely characterize the inherent heterogeneity of hMSCs to guide robust and reproducible stem cell transplantation therapies. 

We created an integrated microfluidic cell separation system that incorporates hydrophoresis and dielectrophoresis modules to facilitate high-throughput continuous cell separation. The hydrophoresis module consists of a serpentine channel with ridges and trenches to generate a diverging fluid flow that focuses cells into two streams along the channel edges. The dielectrophoresis module is composed of a chevron-shaped electrode array. Separation in the dielectrophoresis module is driven by inherent cell electrophysiological properties and does not require cell-type-specific labels. The chevron shape of the electrode array couples with fluid flow in the channel to enable continuous sorting of cells to increase throughput. We tested the new system with mouse neural stem cells since their electrophysiological properties reflect their differentiation capacity (e.g., whether they will differentiate into astrocytes or neurons). The goal of our experiments was to enrich astrocyte-biased cells. Sorting parameters were optimized for each batch of neural stem cells to ensure effective and consistent separations. The continuous sorting design of the device significantly improved sorting throughput and reproducibility. Sorting yielded two cell fractions, and we found that astrocyte-biased cells were enriched in one fraction and depleted from the other. This is an advantage of the new continuous sorting device over traditional dielectrophoresis-based sorting platforms that target a subset of cells for enrichment but do not provide a corresponding depleted population. The new microfluidic dielectrophoresis cell separation system improves label-free cell sorting by increasing throughput and delivering enriched and depleted cell subpopulations in a single sort. 

A<sc>bstract</sc> A search for beyond-the-standard-model neutral Higgs bosons decaying to a pair of bottom quarks, and produced in association with at least one additional bottom quark, is performed with the CMS detector. The data were recorded in proton-proton collisions at a centre-of-mass energy of 13 TeV at the CERN LHC and correspond to an integrated luminosity of 36.7–126.9 fb⁻¹, depending on the probed mass range. No signal above the standard model background expectation is observed. Upper limits on the production cross section times branching fraction are set for Higgs bosons in the mass range of 125–1800 GeV. The results are interpreted in benchmark scenarios of the minimal supersymmetric standard model, as well as suitable classes of two-Higgs-doublet models. 

A search for heavy neutral gauge bosons ( $Z^{\prime }$) decaying into a pair of tau leptons is performed in proton-proton collisions at $\sqrt{s}=13\mathrm{TeV}$at the CERN LHC. The data were collected with the CMS detector and correspond to an integrated luminosity of $138{\mathrm{fb}}^{-1}$. The observations are found to be in agreement with the expectation from standard model processes. Limits at 95% confidence level are set on the product of the $Z^{\prime }$production cross section and its branching fraction to tau lepton pairs for a range of $Z^{\prime }$boson masses. For a narrow resonance in the sequential standard model scenario, a $Z^{\prime }$boson with a mass below 3.5 TeV is excluded. This is the most stringent limit to date from this type of search. © 2025 CERN, for the CMS Collaboration2025CERN 

We report an improved measurement of the valence $u$and $d$quark distributions from the forward-backward asymmetry in the Drell-Yan process using $8.6{\mathrm{fb}}^{-1}$of data collected with the D0 detector in $p\overline{p}$collisions at $\sqrt{s}=1.96$. This analysis provides the values of new structure parameters that are directly related to the valence up and down quark distributions in the proton. In other experimental results measuring the quark content of the proton, $d$quark contributions are mixed with those from other quark flavors. In this measurement, the $u$and $d$quark contributions are separately extracted by applying a factorization of the QCD and electroweak portions of the forward-backward asymmetry. Published by the American Physical Society2024