23,500 results match your criteria: "CA 94720; Kavli Energy NanoSciences Institute[Affiliation]"

Anisotropic Ferroelectricity in Polar Vortices.

Adv Mater

January 2025

Department of Materials Science and Engineering, University of California, Berkeley, CA, 94720, USA.

The exotic polarization configurations of topologically protected dipolar textures have opened new avenues for realizing novel phenomena absent in traditional ferroelectric systems. While multiple recent studies have revealed a diverse array of emergent properties in such polar topologies, the details of their atomic and mesoscale structures remain incomplete. Through atomic- and meso-scale imaging techniques, the emergence of a macroscopic ferroelectric polarization along both principal axes of the vortex lattice while performing phase-field modeling to probe the atomic scale origins of these distinct polarization components is demonstrated.

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Ongoing soil salinization severely hampers plant growth and the sustainability of global crops production. Hydrogen sulfide (HS), acting as a critical gaseous signaling molecule, plays a vital role in plant response to various environmental cues such as salt stress. Nonetheless, it is not well understood how the transcriptional network regulates HS production in response to salt stress in tomato.

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Controlled modifications of amino acids are an indispensable tool for advancing fundamental and translational research based on peptides and proteins. Yet, we still lack methods to chemically modify each naturally occurring amino acid sidechain. To help address this gap, we show that N,α-diaryl oxaziridines expand the scope of bioconjugation methods to chemically modify cysteine, methionine, and tryptophan residues with evidence for additional tyrosine labelling in a proteomic context.

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Hyaluronic acid (HA), the primary component of brain extracellular matrix, is increasingly used to model neuropathological processes, including glioblastoma (GBM) tumor invasion. While elastic hydrogels based on crosslinked low-molecular-weight (LMW) HA are widely exploited for this purpose and have proven valuable for discovery and screening, brain tissue is both viscoelastic and rich in high-MW (HMW) HA, and it remains unclear how these differences influence invasion. To address this question, hydrogels comprised of either HMW (1.

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Objectives: In 2016, the Department of Veterans Affairs (VA) and the Department of Energy (DOE) established an Interagency Agreement (IAA), the Million Veteran Program-Computational Health Analytics for Medical Precision to Improve Outcomes Now (MVP-CHAMPION) research collaboration.

Materials And Methods: Oversight fell under the VA Office of Research Development (VA ORD) and DOE headquarters. An Executive Committee and 2 senior scientific liaisons work with VA and DOE leadership to optimize efforts in the service of shared scientific goals.

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Termites digest wood using Carbohydrate-Active Enzymes (CAZymes) produced by gut bacteria with whom they have cospeciated at geological timescales. Whether CAZymes were encoded in the genomes of their ancestor's gut bacteria and transmitted to modern termites or acquired more recently from bacteria not associated with termites is unclear. We used gut metagenomes from 195 termites and one Cryptocercus, the sister group of termites, to investigate the evolution of termite gut bacterial CAZymes.

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The cation-independent mannose 6-phosphate receptor (CI-MPR) is clinically significant in the treatment of patients with lysosomal storage diseases because it functions in the biogenesis of lysosomes by transporting mannose 6-phosphate (M6P)-containing lysosomal enzymes to endosomal compartments. CI-MPR is multifunctional and modulates embryonic growth and fetal size by downregulating circulating levels of the peptide hormone insulin-like growth factor 2 (IGF2). The extracellular region of CI-MPR comprises 15 homologous domains with binding sites for M6P-containing ligands located in domains 3, 5, 9, and 15, whereas IGF2 interacts with residues in domain 11.

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In response to stresses on water demands, some regions augment conventional drinking water sources with alternative water supplies such as desalinated seawater and reclaimed wastewater. The advanced treatment of wastewater by reverse osmosis, microfiltration, and advanced oxidation processes can produce high quality water for potable uses. However, if not appropriately stabilized, the resulting water can be corrosive to metal-based distribution pipes and plumbing materials.

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Microtubule (MT) and F-actin cytoskeletal cross-talk and organization are important aspects of axon guidance mechanisms, but how associated proteins facilitate this function remains largely unknown. While the MT-associated protein, CKAP5 (XMAP215/ch-TOG), has been best characterized as a MT polymerase, we have recently highlighted a novel role for CKAP5 in facilitating interactions between MT and F-actin and in embryonic neuronal growth cones. However, the mechanism by which it does so is unclear.

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Synaptic plasticity, the dynamic tuning of signal transmission strength between neurons, serves as a fundamental basis for memory and learning in biological organisms. This adaptive nature of synapses is considered one of the key features contributing to the superior energy efficiency of the brain. Here, we use molecular dynamics simulations to demonstrate synaptic-like plasticity in a subnanoporous two-dimensional membrane.

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Article Synopsis
  • In Finland, isolated cleft palate (CP) occurs more frequently than cleft lip with or without cleft palate (CL/P), which is the opposite trend seen in other European countries.
  • A genome-wide association study revealed a specific single nucleotide polymorphism (rs570516915) strongly linked to CP in the Finnish population, showing significant statistical results and confirmed in other cohorts.
  • The risk allele for rs570516915 disrupts a binding site for the IRF6 transcription factor, leading to decreased IRF6 expression, indicating that this genetic alteration may be a key factor in the mechanism causing CP.
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Designing small-molecule and macromolecule sensors for imaging redox-active transition metal signaling.

Curr Opin Chem Biol

December 2024

Department of Chemistry, Princeton University, Princeton, NJ 08540, USA; Department of Chemistry, University of California, Berkeley, Berkeley, CA 94720, USA; Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA. Electronic address:

Transition metals play essential roles in biology, where these nutrients regulate protein activity as active site cofactors or via metalloallostery. In contrast, dysregulation of transition metal homeostasis can lead to unique metal-dependent signaling pathways connected to aging and disease, such as cuproptosis and ferroptosis for copper- and iron-dependent cell death or cuproplasia and ferroplasia for copper- and iron-dependent cell growth and proliferation, respectively. New methods that enable detection of bioavailable transition metal pools with both metal and oxidation state specificity can help decipher their contributions to health and disease.

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Cells adapt to environments and tune gene expression by controlling the concentrations of proteins and their kinetics in regulatory networks. In both eukaryotes and prokaryotes, experiments and theory increasingly attest that these networks can and do consume biochemical energy. How does this dissipation enable cellular behaviors forbidden in equilibrium? This open question demands quantitative models that transcend thermodynamic equilibrium.

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  • High-resolution seismic tomography reveals low shear velocity channels, or "fingers," in the Earth's mantle beneath the south and central Atlantic Ocean, aligned with the mid-Atlantic ridge and indicating the flow of material over long distances.
  • These "fingers" correspond to different groups of mantle plumes that originate from the core-mantle boundary, influencing hotspots and volcanic activity, but their locations often differ from where the plumes are rooted.
  • The study suggests that these mantle plumes interact with upper mantle circulation and highlights that the African low shear velocity province is composed of diverse, chemically distinct plumes rather than a single mass of rising material.
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Genomes OnLine Database (GOLD) v.10: new features and updates.

Nucleic Acids Res

January 2025

DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720, USA.

The Genomes OnLine Database (GOLD; https://gold.jgi.doe.

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Microbes drive fundamental ecosystem processes, such as decomposition. Environmental stressors are known to affect microbes, their fitness, and the ecosystem functions that they perform; yet, understanding the causal mechanisms behind this influence has been difficult. We used leaf litter on soil surface as a model in situ system to assess changes in bacterial genomic traits and decomposition rates for 18 months with drought as a stressor.

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Longitudinal relationships between Aβ and tau to executive function and memory in cognitively normal older adults.

Neurobiol Aging

January 2025

Department of Neuroscience, University of California Berkeley, Berkeley, CA 94720, USA; Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.

The early accumulation of AD pathology such as Aβ and tau in cognitively normal older people is predictive of cognitive decline, but it has been difficult to dissociate the cognitive effects of these two proteins. Early Aβ and tau target distinct brain regions that have different functional roles. Here, we assessed specific longitudinal pathology-cognition associations in seventy-six cognitively normal older adults from the Berkeley Aging Cohort Study who underwent longitudinal PiB PET, FTP PET, and cognitive assessments.

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The concept of group and the theory of perception.

Vision Res

December 2024

Department of Neuroscience, University of California, 142 Weill Hall, Berkeley, CA 94720-3200, United States. Electronic address:

Prompted by the title of Ernst Cassirer's 1944 essay, the origin of the idea of a Group theoretical approach, in the mathematical sense, in vision science is here explored, as well as the several ways in which its implementation had been attempted. That object recognition might proceed by a more generative approach rather than by separate individual cataloging had already been argued by Kant, and Cassirer examined how mathematical group theory might be called on for this purpose, in view of the success of its use in geometry and in the physical sciences. However, such a promise appears unlikely in view of the categorical differences between analysis of mental phenomena and of the physical world.

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The 26S proteasome is the major compartmental protease in eukaryotic cells, responsible for the ATP-dependent turnover of obsolete, damaged, or misfolded proteins that are delivered for degradation through attached ubiquitin modifications. In addition to targeting substrates to the proteasome, ubiquitin was recently shown to promote degradation initiation by directly modulating the conformational switching of the proteasome, yet the underlying mechanisms are unknown. Here, we used biochemical, mutational, and single-molecule FRET-based approaches to show that the proteasomal deubiquitinase Rpn11 functions as an allosteric sensor and facilitates the early steps of degradation.

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Article Synopsis
  • Transcription factors bind to DNA and kickstart gene transcription, often featuring disordered regions called activation domains (ADs) that affect their functionality.
  • These ADs don’t have a fixed shape; instead, they exist in multiple conformations that are influenced by their amino acid sequences.
  • In a study measuring the structural dimensions of two ADs (HIF-1α and CITED2) using FRET microscopy, it was found that altering the shape of HIF-1α influenced its ability to activate transcription, while CITED2's activity remained unaffected by its structural changes.
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For decades since the development of phase-contrast optical microscopy, an analogous approach has been sought for maximizing the image contrast of weakly-scattering objects in transmission electron microscopy (TEM). The recent development of the laser phase plate (LPP) has demonstrated that an amplified, focused laser standing wave provides stable, tunable phase shift to the high-energy electron beam, achieving phase-contrast TEM. Building on proof-of-concept experimental demonstrations, this paper explores design improvements tailored to biological imaging.

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A self-regenerative heat pump based on a dual-functional relaxor ferroelectric polymer.

Science

November 2024

Department of Materials Science and Engineering, Henry Samueli School of Engineering and Applied Science, University of California, Los Angeles, Los Angeles, CA 90095, USA.

Electrocaloric (EC) cooling presents a promising approach to efficient and compact solid-state heat pumps. However, reported EC coolers have complex architectures and limited cooling temperature lift. In this work, we introduce a self-regenerative heat pump (SRHP) using a cascade of EC polymer film stacks, which have electrostrictive actuations in response to an electric field that are directed to realize efficient heat transfer, eliminating the need for additional transportive or regenerative mechanisms.

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Linear magnetoresistance from glassy orders.

Proc Natl Acad Sci U S A

November 2024

Department of Physics, Carnegie Mellon University, Pittsburgh, PA 15213.

Several strongly correlated metals display B-linear magnetoresistance (LMR) with a universal slope, in sharp contrast to the [Formula: see text] scaling predicted by Fermi liquid theory. We provide a unifying explanation of the origin of LMR by focusing on a common feature in their phase diagrams-proximity to symmetry-breaking orders. Specifically, we demonstrate via two microscopic models that LMR with a universal slope arises ubiquitously near ordered phases, provided the order parameter either i) has a finite wave-vector, or ii) has nodes on the Fermi surface.

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Automated live-cell single-molecule tracking in enteroid monolayers reveals transcription factor dynamics probing lineage-determining function.

Cell Rep

November 2024

Department of Molecular and Cell Biology, Li Ka Shing Center for Biomedical and Health Sciences, California Institute for Regenerative Medicine (CIRM) Center of Excellence, University of California, Berkeley, Berkeley, CA 94720, USA. Electronic address:

Lineage transcription factors (TFs) provide one regulatory level of differentiation crucial for the generation and maintenance of healthy tissues. To probe TF function by measuring their dynamics during adult intestinal homeostasis, we established HILO-illumination-based live-cell single-molecule tracking (SMT) in mouse small intestinal enteroid monolayers recapitulating tissue differentiation hierarchies in vitro. To increase the throughput, capture cellular features, and correlate morphological characteristics with diffusion parameters, we developed an automated imaging and analysis pipeline, broadly applicable to two-dimensional culture systems.

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  • Amphibians are a diverse group of tetrapods facing significant threats, with about 41% of species at risk of extinction due to various factors like habitat loss and climate change.
  • Genomic research on amphibians is critical for understanding their biology, including unique traits like tissue regeneration and adaptation, yet it has lagged behind other vertebrates due to technical challenges.
  • The newly formed Amphibian Genomics Consortium (AGC) aims to enhance global collaboration and accelerate genomic research in amphibians, with over 282 members from 41 countries already involved.
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